A piston blank (39) for a piston (8) for use in an internal combustion engine. The piston blank (39) is manufactured at least in sections from a steel alloy which includes a chromium content of 0.5 to 2 percent by weight and a silicon content of 2.5 to 3.5 percent by weight.
A cylinder liner (8) for an internal combustion engine (7), comprising a middle axis (9), and an inner surface (11) running around the middle axis (9). The inner surface (11) comprises a first zone (21), and a second zone (22), which differs from the first zone. The first zone (21) comprises a reduced peak height Rpk of less than 0.2 μm, a core roughness depth Rk of 0.05 to 0.35 μm and a reduced groove depth Rvk of 1.5 to 2.5 μm. The second zone (22) comprises a reduced peak height Rpk of less than 0.2 μm, a core roughness depth Rk of 0.05 to 0.35 μm and a reduced groove depth Rvk of 0.5 to 2.5 μm.
The invention relates to a piston (8A, 8B) for a hydrogen-operated internal combustion engine (7), comprising a piston head (11), a piston skirt (10) connected to the piston head (11), and a combustion bowl (24) provided on the piston head (11), wherein the piston (8A, 8B) has a piston diameter (32) which can be measured on the piston skirt (10), wherein the combustion bowl (24) has a minimum combustion bowl volume (29), the magnitude of which is 2.9674 times the magnitude of the piston diameter (32) minus 220.68, and wherein the combustion bowl (24) has maximum combustion bowl volume (29), the magnitude of which is 4.1893 times the magnitude of the piston diameter (32) minus 311.55.
F02F 3/26 - Pistons having combustion chamber in piston head
F02B 23/10 - Other engines characterised by special shape or construction of combustion chambers to improve operation with positive ignition with separate admission of air and fuel into cylinder
Disclosed is a piston blank (39) for a piston (8), said piston blank (39) being made at least in part of a steel alloy containing 0.5 to 2 percent by weight chromium and 2.5 to 3.5 percent by weight silicon.
The invention relates to a cylinder liner (8) for an internal combustion engine (7), having a central axis (9) and an inner surface (11) which encircles the central axis (9). The inner surface (11) has a first zone (21) which encircles the central axis (9) and a second zone (22) which differs from the first zone (21) and encircles the central axis (9). The first zone (21) and the second zone (22) are arranged next to each other when viewed along the central axis (9), the first zone (21) has a reduced peak height (Rpk) of less than 0.2 µm, a core roughness depth (Rk) of 0.05 to 0.35 µm, and a reduced valley depth (Rvk ) of 1.5 to 2.5 µm, and the second zone (22) has a reduced peak height (Rpk) of less than 0.2 µm, a core roughness depth (Rk) of 0.05 to 0.35, and a reduced valley depth (Rvk) of 0.5 to 2.5 µm.
Piston blank for a piston, comprising a piston lower part, which comprises a first joining surface running around a central axis of the piston blank, and a piston upper part, which comprises a second joining surface running around the central axis and an inner surface running around the central axis and adjoining the second joining surface as viewed along the central axis, wherein the piston upper part can be placed with its second joining surface on the first joining surface, and wherein a tangential plane which is assigned to the second joining surface is inclined relative to the central axis such that the tangential plane intersects the inner surface.
A piston for an internal combustion engine, said piston having an upper piston portion (1) in which a ring zone (2) is located, and a piston lower part (3) having two opposing, load-carrying skirt wall sections (4,5) on the pressure- and counter-pressure sides of the piston adjoins the upper piston portion (1), and the two load-carrying skirt wall sections (4,5) are interconnected via connecting walls (6,7) that are recessed relative to the outer diameter of the piston. Each connecting wall (6, 7) includes a pin bore having a pin bore axis (18) for receiving a pin. The two opposing, load-carrying wall sections (4, 5) have different wall thicknesses and different transition regions at the transition of their lateral skirt connections (8,9 and 16,17) to the recessed connection walls (6,7).
An assembled, oil-cooled piston for reciprocating piston internal combustion engines, with a lower part (1) which receives a gudgeon pin, an upper part (5) which is screwed to the lower part (1) and has a ring belt (7) and a fire land, with an outer cooling ring chamber (11) which adjoins the ring belt (7) and the fire land on the inside in the upper part (5) and the lower part (1), and with a central oil cooling chamber (12) which is arranged within the cooling ring chamber (11), is separated from the cooling ring chamber (11) by means of a supporting collar (6) arranged on the lower part (1) and/or upper part (5), and is connected via bores to the cooling ring chamber (11), characterized in that the upper part (5) and the lower part (1) are screwed to one another by means of a central mating thread pair (9) in the region of the supporting collar (6).
The invention relates to a flexible spring element (1) made of a fibre-reinforced plastics composite material (4, 23), a functional layer (2, 3) made of a fibre-reinforced plastics composite material (4) being located on each of two mutually opposite sides (9, 10) of a central plane of the flexible spring element (1). At least one matrix material discharge layer (17) extending parallel to the two functional layers (2, 3) and in a longitudinal direction (7) is arranged in at least one longitudinal portion (14) and has at least a fraction of discharge layer fibres (18) which are oriented differently from the longitudinal direction (7) of the flexible spring element (1). Within at least one curved portion (13) of the flexible spring element (1) a first volume fraction of flexible spring fibres (5) in the functional layers (2, 3) is smaller, preferably smaller by several % than a second volume fraction of flexible spring fibres (5) in the functional layers (2, 3) within the at least one longitudinal portion (14).
F16F 1/42 - Springs made of plastics, e.g. rubberSprings made of material having high internal friction characterised by the mode of stressing
B29C 70/54 - Component parts, details or accessoriesAuxiliary operations
B29C 70/46 - Shaping or impregnating by compression for producing articles of definite length, i.e. discrete articles using matched moulds, e.g. for deforming sheet moulding compounds [SMC] or prepregs
A piston for an internal combustion engine, said piston having an upper piston region (1) in which a ring zone (2) is located, and a piston lower part (3) having two opposing, load-carrying skirt wall portions (4 and 5) on the pressure- and counter-pressure sides of the piston adjoins the upper piston region (1), and the two load-carrying skirt wall portions (4, 5) are interconnected via connecting walls (6, 7) that are recessed relative to the outer diameter of the piston, wherein provided in each connecting wall (6 and 7) is a pin bore (18) for receiving a pin, and the two opposing, load-carrying wall portions (4 and 5) have different wall thicknesses and different transition regions at the transition of their lateral skirt connections (8, 9 and 16, 17) to the recessed connection walls (6, 7).
A steel piston (1) for a combustion engine, having an upper part in which a ring section (7) with at least one ring groove (8) is arranged, wherein the upper part is adjoined by a lower part that has two opposing skirt wall sections (2), wherein the two skirt wall sections (2) are connected via two mutually opposite case walls (3), wherein a pin bore (4) surrounded by a piston boss (6) is provided in each case wall (3). In one example, there is at least one aperture (14) or at least one recess in the case wall (3) in the region between the piston boss (6) and the skirt wall section (2).
The invention relates to a flexible spring element (1) which is made of a fibre-plastic composite material (4, 22) and has a cover layer (2, 3) made of a first fibre-plastic composite material (4) on each of two outer sides (9, 10) lying opposite one another, fibres (5) being aligned parallel relative to one another at least in bundles within the cover layers (2, 3) and running parallel to the outer side (9, 10) associated with the respective cover layer (2, 3). The flexible spring element (1) has at least one curved portion (13, 14), in which a centre plane (8) of the unloaded flexible spring element (1) running with equal spacing between the two cover layers (2, 3) runs in a curved manner in a longitudinal direction (7) of the flexible spring element (1). The flexible spring element (1) also has at least one longitudinal portion (15, 16, 17) in which the centre plane (8) of the unloaded flexible spring element (1) either has no significant curvature or has a reversal of curvature. In the at least one curved portion (13, 14) the flexible spring element (1) has a spacing extending element (20, 21) which is arranged between the two cover layers (2, 3) and is made of a different material than the two cover layers (2, 3). The material of the spacing extending element (20, 21) may be a second fibre-plastic composite material (22) having short and undirected fibres (23).
The invention relates to a piston for an internal combustion engine, based on an alloy containing at least 71 wt. % aluminium, 10 - 13.5 wt. % silicon and 0.7 - 2.5 wt.% iron.
A gallery-cooled piston (6) with a cooling gallery (9) or a cooling chamber in the region of the piston crown (10) of the gallery-cooled piston (6), wherein at least one opening (11 or 12) which has a funnel-shaped inlet is provided from an inner region (8) of the gallery-cooled piston (6) to the cooling gallery (9) or the cooling chamber, characterized in that a funnel-shaped tube (1) is inserted into and fixed in the at least one opening (11 and/or 12) after the production of the gallery-cooled piston (6).
The invention relates to a process for manufacturing a piston for an internal combustion engine, said piston comprising at least a first piston component and a second piston component which are joined to each other in a welding operation, the welding operation being in the form of a beam welding operation and being carried out in a reduced-pressure environment.
The invention relates to a piston for an internal combustion engine formed from a lower part and an upper part which are threadingly connected to one another to form a piston. In one example, an anti-rotation safeguard device is used to prevent unwanted rotation of the upper part relative to the lower part. In another example, a forged extension and a nut are used to obtain a prestress during operation of the piston. In another example, a cooling gallery including extension bores are used to increase the cooling capacity.
The invention relates to a material composition for a coating for components of internal combustion engines, selected from one of the three material compositions indicated in the following table: formula.
The invention relates to a piston (1), comprising two opposing gudgeon pin bores (2, 3), into which a gudgeon pin can be inserted, which can be axially secured in retaining grooves (4) in the gudgeon pin bores (2 and 3) by means of circlips in order to connect the piston (1) in a per se known manner to a conrod, wherein a groove (5, 6) for lubricating the sliding couple, consisting of gudgeon pin bores (2, 3) and gudgeon pins, is made in the surface of at least one gudgeon pin bore (2 or 3), preferably both gudgeon pin bores (2 and 3).
Piston (1) of an internal combustion engine, which piston is designed in structured construction, comprising two oppositely arranged load-bearing skirt wall portions (2), wherein a connecting wall (3) respectively extends, starting from a pin boss (4), in the direction of the side edge of the load-bearing skirt wall portions (2), characterized in that in an interior of the piston (1) is (are) disposed at least one rib (5, 6, 7), preferably three ribs (5, 6, 7), and the material of the regions around the at least one rib (5, 6, 7) is reduced.
A piston for an internal combustion engine includes a piston upper part and a piston lower part having a cooling channel including at least one inlet opening. A dam-type elevation is formed in the region of the at least one inlet opening through forging of the dam elevation in the cooling channel portion in the piston lower part. In one example, a funnel-shaped inlet contour is formed in the inlet opening by pre-forging. In one example, a V-shaped element is formed in the piston upper part cooling chamber portion in alignment with the inlet opening and used as a coolant jet splitter.
Steel piston (1) for an internal combustion engine, having an upper part, in which a ring section (7) with at least one ring groove (8) is arranged, wherein the upper part is adjoined by a lower part which has two opposite skirt wall portions (2), wherein the two skirt wall portions (2) are connected by means of two oppositely arranged case walls (3), wherein, in each case wall (3), there is provided a pin bore (4) surrounded by a piston boss (6), characterized in that, in the region between the piston boss (6) and the skirt wall portion (2), at least one aperture (14) or at least one depression is provided in the case wall (3).
A piston for use in an internal combustion engine having a two-piece construction including an upper and a lower part. The upper and the lower parts include one or more overlapping cutouts to reduce the weight of the piston. One or more of the cutouts or connecting walls include wall regions that transition to adjacent walls without sharp or abrupt areas. The piston upper and lower parts are permanently joined together. One or more tongue and groove structures are used to provide a locking connection between the piston upper and lower parts.
A piston for an internal combustion engine including an upper part and a lower part connected by at least one threaded connection. The lower part includes a cutout positioned in the inner region of the piston above a peak of the pin bore extending toward the outer periphery of the piston. The lower part further includes at least one web positioned above the pin bore extending toward the outer periphery of the piston.
A composite material selectively applied to at least surface areas of a piston of an internal combustion engine. The composite material contains at least high temperature polymers and/or liquid crystalline polymers (LCP).
The invention relates to a piston (1) of an internal combustion engine, comprising a piston base body (6) and two piston hubs arranged opposite each other and each comprising a pin borehole (4) for receiving a piston pin, at least one cavity (5) being made in the piston base body (6) and sealed by a closing element (7) after a coolant has been introduced into the cavity (5). The invention is characterised in that the closing element (7) is a section of wire, the section of wire being pressed into the cavity (5).
A piston for use in an internal combustion engine having a pressure side and counterpressure side. The piston includes a piston skirt having skirt wall sections and box walls connecting the skirt wall sections. A spacing between the box walls on the pressure side is 35%-51% of the piston diameter and on the counterpressure side is 26%-39% of the piston diameter. Reduced angles of the extraction angle slopes on the pressure and counterpressure sides as well as larger free spaces are achieved which provides for lower piston mass and greater distribution of stresses in the box region of the piston.
Disclosed is a piston (1) of an internal combustion engine, constructed with a structured design and having two supporting shaft wall sections (2) lying opposite one another, with respective connecting walls (3) extending from a piston hub (4) towards the lateral edge of the supporting shaft wall sections (2), characterised in that at least one rib (5; 6; 7), preferably three ribs (5, 6, 7) is (are) provided in an inner region of the piston (1) and the amount of material in the regions surrounding the at least one rib (5; 6; 7) is reduced.
Disclosed is an internal combustion engine piston wherein at least one space is formed into which a coolant is installed. In one example, the coolant is first introduced into a coolant container and the coolant container is thereafter inserted into the at least one space in the piston. In one example, the coolant is an alkali metal consisting of sodium.
The invention discloses a method for producing an internal combustion engine piston having at least one cavity which is filled with an alkali metal cooling medium and is subsequently closed. The at least one cavity longitudinally extends from a central point into the piston body toward the piston circumference. The invention further discloses a piston produced according to the method.
F02F 3/18 - Pistons having cooling means the means being a liquid or solid coolant, e.g. sodium, in a closed chamber in piston
B21K 1/18 - Making machine elements pistons or plungers
B23P 15/10 - Making specific metal objects by operations not covered by a single other subclass or a group in this subclass pistons
F02B 23/06 - Other engines characterised by special shape or construction of combustion chambers to improve operation with compression ignition the combustion space being arranged in working piston
The invention relates to a piston (1) for an internal combustion engine, said piston consisting of an upper portion (2) and a lower portion (3) which are joined together, wherein a cooling channel (8) is provided which has at least one inlet opening (9) and/or at least one outlet opening (13) for a coolant. The piston is characterised in that both a dam-type elevation (10) is formed in the region of the inlet opening (9) and/or the outlet opening (13) by a fully-forged contour of the lower cooling channel region, and the inlet contour (12) of the inlet opening (9) and/or of the outlet opening (13) is formed on the interior (11) of the piston (1) by means of a pre-forging process.
The invention relates to a piston (1) of an internal combustion engine, having an upper part (2) with appended piston bosses (3) and load-bearing skirt wall sections (5), wherein the load-bearing skirt wall sections (5) are arranged in a self-supporting manner on the upper part (2) without any attachment to the piston bosses (3), and wherein a rib (6) extends from the underside of the upper part (2) in the direction of the inner side of the load-bearing skirt wall sections (5).
The invention relates to a piston (1) of an internal combustion engine, having a ring groove region (4), a piston skirt (7) and a piston boss (8) for receiving a piston pin, the piston (1) being formed from two parts which are produced separately from each other and are joined non-detachably together to form the single-piece piston (1), characterised in that the piston (1) is formed from an outer part (2), which includes the ring groove region (4) and the piston skirt (7) and into which is inserted an inner part (3), which includes the piston boss (8) and the pin bores (9), wherein the two parts (2, 3) are joined non-detachably together in at least one vertical plane.
The invention relates to an assembly having a piston (1) of an internal combustion engine, comprising an upper part (2) and a piston skirt (3) adjoining the upper part (2), wherein furthermore a piston pin (4) is fastened to the piston (1) for operative connection to a connecting rod (5), characterized in that the piston pin (4) is fastened at the ends thereof to a bottom side (8) of the upper part (2) by means of respective frictional connecting means on the upper part (2).
A piston, in particular, a gallery-cooled piston for an internal combustion engine has a piston bottom part and a piston upper part which are connected in a joining process to produce the piston. The piston upper part has at least one ring zone and an inner wall. The piston bottom part has a radially circumferential oblique surface at the end which faces the piston upper part. The oblique surface, interacting with the inner wall of the piston upper part, brings about a centering action during the joining process of the piston parts. A joining method for manufacturing a piston is also disclosed.
A cylinder of an internal combustion engine, in which cylinder liner an oscillating piston is guided on a running surface wherein the cylinder line is fixed vertically by means of a collar between a cylinder housing and a cylinder head. The wet cylinder includes an outer side which deviates from a circular shape and/or a rotationally asymmetrical outer contour of the collar. The cylinder liner is fitted in a positionally oriented manner in a corresponding receptable of the cylinder housing.
The invention relates to a method for producing a cooling channel piston, wherein a blank of the cooling channel piston, which has a cavity designed as a cooling channel, is provided and wherein an inlet or outlet opening is introduced into the blank in the direction of the cooling channel, characterized in that the opening is introduced into the blank by means of a CNC-controlled circular milling process by using a special milling cutter having end cutting edges arranged in a shaft profile.
Piston (1) of an internal combustion engine, comprising a piston crown (2) and a piston bottom (3), the piston crown (2) having at least one ring groove region, and the piston bottom being formed by opposite bores (4) and piston skirts (5), a slot (6) being located between the piston crown (2) and at least one piston skirt (5).
A piston (1) of an internal combustion engine, formed by an upper part (3) which is joined together with a lower part (2), wherein the lower part (2) is formed by connecting walls (7) which lie opposite one another and are positioned obliquely and are set back with respect to the external diameter of the piston (1), wherein in each case one connecting wall (7) has a pin bore (4), and the respective end of each connecting wall (7) merges into a piston skirt (6), wherein the lower part (2) has at least one recess (12) which faces in the direction of the upper part (3), and the upper part (3) has at least one recess (5) which faces in the direction of the lower part (2), wherein the recesses (5, 12) overlap after being joined together, wherein, furthermore, a permanent connection between the lower part (2) and the upper part (3) is a positively locking connection, and the positively locking connection is formed by at least one tongue (16) and at least one groove (17) which can be brought into an operative connection with it.
Method for producing a cooling duct piston (10) for an internal combustion engine, which cooling duct piston (10) has a cooling duct (60) in its piston crown, wherein the piston crown (90) is adjoined by a piston lower part (50) with piston bosses (100), pin bores (110) and piston skirts (120), wherein first of all a piston main body (20) is produced with a collar (30) which is circumferential and projects radially in the region of the piston crown, wherein the collar (30) is formed until its outer circumferential edge comes very closely or completely into contact with a bearing region of the piston lower part (50), in order to form the cooling duct (60), and subsequently at least one ring groove (40) is introduced, characterized in that a ring-free groove (80) is formed below the ring groove (40), wherein a dividing plane (70) lies between the outer circumferential edge of the formed collar (30) and an upper side of the piston lower part (50) in the ring-free groove (80).
The invention relates to a piston (50) for internal combustion engines, the piston consisting of a bottom part (2) and a top part (3). At least one upper joining plane (6), which passes through the outer circumference of the piston (50), is formed between the parts (2, 3). In the region of the upper joining plane (6), an upper bottom-part joining surface (16) and an upper top-part joining surface (17) lie opposite one another and/or at least one lower joining plane (15), which does not pass through the outer circumference of the piston (50), is formed between the parts (2, 3). In the region of the lower joining plane (15), a lower bottom-part joining surface (18) and a lower top-part joining surface (19) lie opposite one another, and at least one solder gap (4, 5) is arranged at least in one sub-region of the at least one joining plane (6, 15) between the joining surfaces (16, 17; 18, 19). In the region of the at least one joining plane (6, 15), solder containing iron is inserted between the bottom part (2) and the top part (3). The invention also relates to a number of methods for producing the piston.
Method for producing a piston (8), which has a cooling channel (4) created by means of a lost core (3), wherein, in a casting process using a casting mould into which the core (3) is placed before casting and using a casting melt, a piston blank (1) is cast and, after the casting melt has solidified, the piston blank (1) is removed from the casting mould and the core (3) is subsequently flushed out, and this is followed by the finishing of the cast blank (1) to produce the piston (8), wherein the core (3) extends into a region of the casting mould that forms an inner region of the piston blank (1) and the core (3) is used to form at least one opening having a rounded profile for the cooling channel (4) after the flushing out.
The invention relates to a piston of an internal combustion engine, consisting of an upper part (1) and a lower part (2), which are permanently joined in the region of a joining plane (3) by a friction welding method, wherein the piston has at least one peripheral annular groove (4), characterized in that the joining plane (3) is located between the upper flank and the lower flank of the annular groove (4) and in that a heat-affected zone (5) arising because of the use of the friction welding method includes at least the upper flank and/or the lower flank of the annular groove (4).
B23K 20/12 - Non-electric welding by applying impact or other pressure, with or without the application of heat, e.g. cladding or plating the heat being generated by frictionFriction welding
The invention relates to a piston (1), assembled from an upper part (2), which has a cooling channel (4), and a lower part (3), which has a pin bore (6), wherein the upper part (2) and the lower part (3) have contact surfaces that face each other and the two parts (2, 3) are held together by means of at least one threaded connection (12), wherein the lower part (3), proceeding from the inner region thereof above a peak (8) of the pin bore (6), has a cut-out (10) directed toward an outer periphery (15) and, proceeding from an outer region, has at least one web (13) above the pin bore (6), which web likewise points in the direction of the outer periphery (15).
The invention relates to a piston of an internal combustion engine, comprising a composite material which is applied at least in areas to the surface of the piston, characterized in that the composite material contains at least high temperature polymers and/or liquid crystalline polymers (LCP).
The invention relates to a method for producing a piston, wherein an upper part having at least one joining zone and a lower part having at least one joining zone are produced separately from each other and thereafter are permanently joined to each other in the region of the joining zones by means of a joining method, characterized in that at least one of the joining zones of the upper part and/or of the lower part is heated to the point of melting by means of a resistance welding method and thereafter the two parts are set in rotation in relation to each other and are axially pressed together.
B23K 11/00 - Resistance weldingSevering by resistance heating
B23K 20/04 - Non-electric welding by applying impact or other pressure, with or without the application of heat, e.g. cladding or plating by means of a rolling mill
B23K 20/12 - Non-electric welding by applying impact or other pressure, with or without the application of heat, e.g. cladding or plating the heat being generated by frictionFriction welding
Piston (1) of an internal combustion engine, comprising a piston head (2) that has supporting skirt wall sections (4) which are arranged on the bottom side (3) of the piston head (2) and are connected to connecting walls (5) extending from a pin boss (6), the piston (1) being characterized that the connecting walls (5) are connected in a central zone (11) of the skirt wall section (4), "central" being in relation to the shape of the supporting skirt wall section (4), which is in the form of a segment of a circle.
The invention relates to a piston (11) of an internal combustion engine formed from a lower part (12) and an upper part (13), comprising a piston base, the lower part (12) and the upper part (13) are joined together by an interlocking and/or frictional connection to the piston (11), an outer thread (1, 17) being provided between the lower part (12) and the upper part (13).
The invention relates to a piston (6, 7) of an internal combustion engine, formed by a lower part (1) and an upper part (4), comprising a piston base and a cooling channel, the lower part (1) being connected to the upper part (4) by means of a form-fitting connection. According to the invention, the lower part has a flat joining area with at least one recess and the upper part has a flat joining area as well as an annular recess that extends from the joining area into the lower part, wherein the at least one recess of the lower part is in overlap with a partial area of the annular recess after the form-fitting connection.
The invention relates to a piston (1) of an internal combustion engine, comprising an upper part (2) having a ring zone (6) and piston skirt (3) adjoining the upper part (2), wherein at least one space (12) is formed in the piston (1), into which at least one space a coolant is introduced, wherein the coolant is introduced into a coolant container (13) and the coolant container (13) is inserted into the at least one space (12) in the piston (1).
The invention relates to a piston (1) for an internal combustion engine having an upper part (3) integrally joined to a lower part (2), wherein the lower part (2) comprises a shaft (6) and at least one pin bore (7), wherein the upper part (3) comprises a combustion chamber recess (11) and a piston crown (5) with a crown edge (27), characterized in that at least one join (4) is arranged in the region of a ring zone (9) and in an outer wall of the combustion chamber recess (11), and the ratio of piston compression height (h1) and the diameter of the piston (d1) is less than 0.53.
The invention relates to a method for producing a piston (1) of an internal combustion engine, wherein in the piston (1) at least one cavity (2) is created which is filled with a cooling medium, in particular an alkali metal, and is subsequently closed. The at least one cavity (2) for receiving the cooling medium is designed as a longitudinally extending cavity (2) and, starting from a central hole (10) is introduced in the direction of the piston circumference into the piston body of the piston (1). The invention further relates to a piston (1) produced according to this method.
The invention relates to a piston (1) for an internal combustion engine, comprising a piston shaft (2) and a piston base (3) which is arranged on the piston shaft and which has an annular field (4). The piston shaft (2) has supporting shaft wall portions (5) and box walls (14) which are set back and connect the shaft wall portions (5) together and which progress in a curved manner and have a pin bore (7). An undercut open space (21) is provided in the region of the piston base (3) below the annular field (4) in the region of the pin bore (7). The piston (1) has a pressure side (12) and a counter pressure side (13), and the piston (1) has a spacing (27) between the box walls (14) of 35% to 51% of the piston diameter (20) on the pressure side (12) and/or the piston (1) has a spacing (28) between the box walls (14) of 26% to 39% of the piston diameter (20) on the counter pressure side (13).
The invention relates to a method for producing a cooling channel piston (9) for an internal combustion engine which cooling channel piston has a cooling channel (8) in the piston crown (2) of the cooling channel pistion, wherein the piston crown (2) connects a piston bottom part with piston bosses (4), bolt bores (12), and piston skirts (13), wherein a piston blank (1) having a circumferential collar (3) which protrudes radially in the region of the piston crown (2) is first produced and the collar (3) is then shaped. The method is characterized in that there is a contact region (5) on a top region of the piston skirts (13) and the collar (3) is shaped such that the outer circumferential edge thereof points at a distance to the contact region (5) and forms a defined gap (9), wherein the gap (9) is then sealed by a closure element (10) in order to form a closed cooling channel (8).
The invention relates to a piston for an internal combustion engine, having a piston lower part, an upper part, an internal cooling channel having at least one coolant inlet opening and at least one outlet opening defined by a rim hole. The rim hole having a screw thread into which at least one tubular element is inserted and selectively positioned relative to the cooling channel for regulating the coolant level in a cooling channel.
A piston for an internal combustion engine has a sliding shoe carried in a force accumulator. The sliding shoe has a channel to transfer cooling oil into a hollow space. The force accumulator is located is a channel formed by the piston, and the sliding shoe is guided partially inside the force accumulator.
Disclosed is a method for manufacturing a piston, wherein a piston blank (1) is initially made and is then finish-machined, characterized in that while or after making the piston blank (1), same is provided with a section having a peripheral surface that has at least two distinct corners and/or bulges in order to be able to clamp the piston blank (1) for a subsequent machining operation.
The invention relates to a coating for components of internal combustion engines, in particular for cylinder and/or piston surfaces, the coating comprising chromium with a mass fraction of between 1 and 30%, preferably between 5 and 20%, in particular 11%, the coating comprising iron with a mass fraction of between 0 and 50%, preferably between 15 and 35%, in particular 25%, the coating comprising carbides and/or oxides with a mass fraction of between 0 and 50%, preferably between 15 and 35%, in particular 25%, and the coating comprising a solid lubricant with a mass fraction of between 0 and 30%, preferably between 5 and 15%, in particular 10%.
The invention relates to a piston (1) of an internal combustion engine, made of a lower part (2) and an upper part (3), having a piston base (17), which is exposed to at least one combustion jet, and a cooling channel (9), in which a separating element with at least one opening (16) is positioned. At least one pressure chamber (12) is provided below the at least one opening (16), said pressure chamber being filled with pressurized oil, and the opening (16) is designed such that the oil is continuously injected into the cooling channel (9). The separating element is designed as a cooling oil ring (20, 50, 80), and the cooling oil ring (20, 50, 80) has a height (H1) which equals at least half of the total height (H2) of the cooling channel (9).
A method for producing a piston for internal combustion engines, where the piston includes a circumferential trapezoid annular groove for receiving trapezoid rings with small axial dimensions the groove having a groove base with adjoining surfaces and groove flanks. The groove base with adjoining surfaces is created in a first method step by machining using a cutting steel tool and the groove flanks are created in a further method step. Also disclosed are a piston produced according to the method and a cutting steel tool.
The invention relates to a cooling-channel piston (1, 100) for an internal combustion engine, having an upper part (2, 102) and a lower part (3, 103), wherein said two parts (2, 3; 102, 103) are connected to one another by way of a cohesive joint in the form of a weld seam (11), and said two parts (2, 3; 102, 103) form an annularly encircling cooling channel (6) which is arranged approximately behind a ring section (4), wherein a gap geometry (13, 113) is provided between a lower edge (16) of the ring section (4) and an upper edge (17) of a lower part (3, 103), wherein the gap geometry (3, 113) has at least one sliding surface (19) which is arranged on a lower edge (16) of the ring section (4) of the cooling-channel piston (1, 100) and/or on the corresponding upper edge (17) of a lower part (3, 103) of the cooling-channel piston (1, 100), and to several methods for the operation of a cooling-channel piston.
06 - Common metals and ores; objects made of metal
07 - Machines and machine tools
Goods & Services
Common metals and their alloys; light metal alloys; metal
alloys for manufacturing pistons and cylinders for
combustion engines. Machine parts, included in this class; pistons; piston pins
and piston rings; cylinders; cylinder heads; liner sleeves
for cylinders for internal combustion engines.
63.
LAYER-BY-LAYER PRODUCTION METHOD DURING LASER MELTING (SLS) IN GRAVITY DIE CASTING OPERATIONS
The invention relates to the use of direct metal laser sintering (DMLS) for the production of a casting mold, in particular a permanent mold, in order to avoid air pockets in internal combustion engine pistons manufactured in a gravity die casting process, wherein at least one portion of the casting mold has a plurality of small openings, in particular microscopic holes, for discharging air. The invention also relates to a method for producing a casting mold, in particular a permanent mold, for gravity die casting pistons for internal combustion engines.
The invention relates to a piston (1), in particular for an internal combustion engine, having a piston lower part (2) and a piston upper part (3), having an internally situated, preferably ring-shaped cooling channel (5), and having at least one inlet opening (10) arranged on the piston lower part (2) and at least one outlet opening (11) arranged on the piston lower part (2), via which inlet opening and outlet opening an inflow of coolant into and an outflow of coolant out of the cooling channel (5) take place, wherein the at least one inlet opening (10) and/or the at least one outlet opening (11) are/is formed by a rim hole (12), and the latter is formed integrally with the piston lower part (2), wherein the at least one rim hole (12) has a screw thread (14) into which at least one tubular element (15, 115) is inserted. The invention also relates to a method for regulating the coolant level in a cooling channel (5) of a piston (1), in particular for internal combustion engines, which has at least one inlet opening (10) and/or outlet opening (11) in the cooling channel (5), formed by a rim hole (12), wherein the coolant level in the cooling channel (5) is set by way of an adjustable tubular element (15, 115).
F02F 3/22 - Pistons having cooling means the means being a fluid flowing through or along piston the fluid being liquid
68.
PISTON WITHOUT A CLOSED COOLING CHAMBER FOR INTERNAL COMBUSTION ENGINES WITH AT LEAST ONE COOLING OIL NOZZLE PER CYLINDER AND METHOD FOR COOLING SAID PISTON
The invention relates to a piston (1, 100) for internal combustion engines, comprising a ring field (3), a shaft (4) as well as pin boss bores (5) and a cooling chamber (8) which is open in the direction of the pin boss bores (5). The invention also relates to a method for cooling said piston (1, 100).
The invention relates to a piston (1, 100, 200, 300) for internal combustion engines, comprising a ring field (3), a shaft (4) and pin boss bores (5) and at least one cooling chamber (7) with oil guiding surfaces (10), at least one oil guiding surface (10) having a slope and to a method for cooling said piston (1, 100, 200, 300).
The invention relates to a piston (1) of an internal combustion engine having a piston head (11) which has a ring zone (12) and is adjoined by a piston skirt (2) which encloses an inner shape (10), with two box walls (4) which lie opposite one another and are set back with respect to the outer contour of the piston (1) and with two skirt walls (13) which are not set back with respect to the outer contour of the piston (1), wherein the box walls (4) receive hubs (6), wherein the piston skirt (2) has skirt supports (3) which are connected to the hub (6), wherein the width (b) of the box wall (4) is a point of intersection between the pin axis (7) and the constant-curvature and constant-tangent further course of the box wall (4), and to a method for producing a piston (1) for internal combustion engines.
The invention relates to a piston (1) of an internal combustion engine, wherein the piston (1) comprises a slide shoe (4) mounted in a force accumulator (5) and said slide shoe (4) has a channel (10) for transferring cooling oil into a hollow space (11), characterized in that the force accumulator (5) is arranged in a channel (12) formed by, in particular, the piston (1) and the slide shoe (4) is partially guided within the force accumulator (5).
The invention relates to a piston (1), especially a steel piston for an internal combustion engine, comprising a piston head (2) which forms part of a combustion chamber (3), at least the piston head (2) having an oxidation protection layer. The invention further relates to a method for producing an oxidation protection layer.
The invention relates to a method for producing a piston (1) for internal combustion engines, especially a cooling duct piston, comprising a piston lower part (2) and a piston upper part (3), wherein an internal contour (11) is machined from the piston (1), particularly the piston lower part (2), by rotary machining. The invention also relates to a piston produced according to said method.
A method for producing a piston for an internal combustion engine, which piston has at least one cooling channel and is produced from at least one upper part and one lower part. The cooling channel of the piston is formed of the upper part and the lower part where the upper part and the lower part of the piston are each produced by means of a forging process At least one rib-like element, in particular, at least one rib, is additionally forged during the forging of the upper part in an area of the cooling channel and/or at least one rib-like element, in particular, at least one rib, is additionally forged during the forging of the lower part in an area of the cooling channel. Two alternative production methods and to a piston for an internal combustion engine are disclosed.
The invention relates to a method for producing a piston (1) for internal combustion engines, said piston comprising a circumferential trapezoid annular groove (2) for receiving trapezoid rings with small axial dimensions and the groove having a groove base (5) with adjoining surfaces (6, 7) and groove flanks (3, 4). According to the invention, the groove base (5) with adjoining surfaces (6, 7) is created in a first method step by machining using a cutting steel (15) and the groove flanks (3, 4) are created in a further method step. Also disclosed are a piston (1) produced according to the claimed method and a cutting steel (15).
The invention relates to a piston (1, 1''), in particular gallery cooled piston, of an internal combustion engine, comprising at least one bottom part (2, 2'') and at least one top part (3, 3', 3''), wherein the at least two piston parts (2, 2'', 3, 3', 3'') have geometries which correspond in the connecting region thereof, in order to bring about a positively locking connection. Furthermore, the invention relates to a method for producing a piston.
The invention relates to a piston (10), in particular a cooling channel piston, for an internal combustion engine, comprising at least one lower part (2) and one upper part (3), a combustion chamber (13) and at least one annular groove (11), wherein the upper part (3) or the lower part (2) is fastened by means of at least one undercut on the lower part (2) or on the upper part (3), characterised in that the upper part (3) comprises at least one combustion chamber (13) and at least one annular groove (11). The invention further relates to a method for producing such a piston.
The invention relates to a method for producing a cooling duct piston (1) for an internal combustion engine, said cooling duct piston (1) having a cooling duct (3) in its piston head (2), wherein the piston head (2) is adjoined by a piston bottom part (4) having piston bosses (5), pin bores (6) and piston skirts (7), wherein first of all a piston blank (1') having a circumferential collar (9) that protrudes radially in the region of the piston head (2) and having an abutment region (11) for the collar (9) in the transition region (10) between the piston head (2) and the piston bottom part (4) is produced, wherein the collar (9) is subsequently reshaped such that the outer radial circumferential edge (12) thereof comes virtually or completely into abutment with the abutment region (11). Provision is made according to the invention for at least a region of the piston blank (1') to be plastically deformed shortly before or after abutment, such that the collar (9) and the abutment region (11) are connected together so as to be detachable to a limited extent or non-detachable, with the result that a completely closed cooling duct (3) is formed. Furthermore, the invention relates to a cooling duct piston (1).
The invention relates to a piston (1) for an internal combustion engine, configured as a gallery-cooled piston of two-piece construction which comprises a main body (2) and a ring element (3). The ring element (2) which has a ring zone (18) and a fire land (17) encloses a cooling gallery (15) on the outside, which cooling gallery (15) is delimited on the inside by an intermediate wall (16) which separates the cooling gallery (15) from a combustion-chamber recess (12) which is made in a piston head (10) of the main body (2). The main body (2) and the ring element (3) together form two circumferential dividing planes (4a, 5a) which are offset with respect to one another, to which end in each case two interacting joining webs (6a, 6b; 7a, 7b) of the ring element (3) and of the main body (2) are connected with a material-to-material bond.
The present invention relates to a piston (1, 31), in particular a gallery-cooled piston for an internal combustion engine, having a piston bottom part (2, 32) and a piston top part (3, 33) which are connected in a joining process to produce the piston (1, 31), wherein the piston top part (3, 33) has at least one ring zone (16) and an inner wall (7), wherein it is provided according to the invention that the piston bottom part (2, 32) has a radially circumferential oblique surface (6) at the end which faces the piston top part (3, 33), which oblique surface (6), interacting with the inner wall (7) of the piston top part (3, 33), brings about a centring action (10) during the joining process of the piston parts (2, 3; 32, 33). Furthermore, the invention relates to a joining method for manufacturing a piston.
The invention relates to a method for producing a cooling duct piston (1) for an internal combustion engine, having the following steps of: producing a top piston part (6) by introducing a combustion bowl, a cooling space (4) of a part of a cooling duct (2) and also overflow ducts (5), producing a bottom piston part (7) by introducing a part of a cooling duct, and joining the piston parts, wherein at least one transfer duct is created by bores. Also claimed is a cooling duct piston produced by the method according to the invention.
Method for producing a piston (2) with a cooling duct for an internal combustion engine, comprising a cooling duct (5) in the piston head thereof, wherein a piston blank (1) is provided and a collar (K), protruding beyond the outer diameter of the later piston (2) with a cooling duct, is formed on the piston blank (1) by forging, spin-bending or the like and, to form the cooling duct (5), a radially peripheral recess (A) is introduced into the piston blank (1), characterized in that the radially peripheral recess (A) is introduced into the piston blank (1) by forging, spin-bending or the like and, in a further method step, a forming operation is performed on the collar (K), which together with the peripheral recess (A) forms a cooling duct.
A piston for internal combustion engines has a skirt coating consisting of a wear resistant inner layer consisting of a polymer matrix having ceramic particles, aramide fibers and/or carbon fibers dispersed therein and an outer layer consisting of a polymer matrix having solid lubricants dispersed therein and an outer layer consisting of a polymer matrix having solid lubricants dispersed therein.
C10M 111/04 - Lubricating compositions characterised by the base-material being a mixture of two or more compounds covered by more than one of the main groups , each of these compounds being essential at least one of them being a macromolecular organic compound
The invention relates to a method for producing a cooling channel piston which has a cooling channel approximately in the region behind a ring field. A piston blank (1) is formed in a forging method, and at least one peripheral collar (3) is likewise formed in the forging method, in particular approximately in the region of a top land. The collar is formed by means of a forming process such that the recess for forming the cooling channel is closed by the at least one collar (3), and the free end region of the collar is brought into contact with the piston blank. The invention is characterized in that the recess is introduced by a forging method.
The invention relates to a piston of an internal combustion engine, which piston forms a single-piece piston (1a) according to the production thereof and comprises a piston upper part (2a) and a piston lower part (3a) which are supported via corresponding joining webs (4a, 5a; 6a, 7a), in each case forming a joining zone (8a, 9a), and are connected in a material-to-material manner by means of a multi-orbital rotary friction weld. Here, the joining webs (4a, 5a) and (6a, 7a) which are in each case directly connected have a wall thickness S1, S2 which is identical as far as possible. The piston (1a) encloses a combustion-chamber recess (15a) and at least one cooling duct (18a) which are made centrally or eccentrically in the piston (1a). Here, the combustion-chamber recess (15a) and the cooling duct (18a) form a circular contour or a contour which deviates from a circular shape.
In order to machine at least one workpiece (1) on a lathe, wherein the workpiece (1) rotates in the lathe and the at least one region to be machined of the workpiece (1) is machined with the aid of at least one tool (3) of the lathe, wherein the tool (3) is moved at least parallel to the rotation axis (2) of the workpiece (1), according to the invention the tool (3) is moved parallel to the rotation axis (2) of the workpiece (1) such that the machined region of the workpiece (1) is formed in a rotationally asymmetrical manner with respect to the rotation axis (2) of the workpiece (1) after machining. Furthermore, the invention relates to a cooling duct (7), to a piston wall (13) and to a combustion-chamber hollow (9) of a piston (6) and also to a lathe.
G05B 19/18 - Numerical control [NC], i.e. automatically operating machines, in particular machine tools, e.g. in a manufacturing environment, so as to execute positioning, movement or co-ordinated operations by means of programme data in numerical form
B23P 15/10 - Making specific metal objects by operations not covered by a single other subclass or a group in this subclass pistons
The invention relates to the machine processing of a piston (1) for an internal combustion engine on a lathe, wherein the piston (1) rotates in the lathe and the at least one region of the piston (1) to be processed is processed with the aid of at least one tool (8) of the lathe, wherein the tool (8) is moved at least parallel to the rotation axis of the piston (1) and the processed region is designed as a combustion bowl (3) based on the rotation axis of the piston (1). According to the invention, the tool (8) is moved parallel to the rotation axis of the piston (1) such that the processed region of the piston (1) is designed as a rotation-symmetrical combustion bowl (3) based on the rotation axis of the piston (1) after processing. The invention further relates to a piston (1), an injection nozzle (7) and an internal combustion engine, preferably a diesel internal combustion engine.
G05B 19/18 - Numerical control [NC], i.e. automatically operating machines, in particular machine tools, e.g. in a manufacturing environment, so as to execute positioning, movement or co-ordinated operations by means of programme data in numerical form
B23P 15/10 - Making specific metal objects by operations not covered by a single other subclass or a group in this subclass pistons
B23B 5/18 - Turning-machines or devices specially adapted for particular workAccessories specially adapted therefor for turning crankshafts, eccentrics, or cams, e.g. crankpin lathes
B23B 5/36 - Turning-machines or devices specially adapted for particular workAccessories specially adapted therefor for turning specially-shaped surfaces by making use of relative movement of the tool and work produced by geometrical mechanisms, i.e. forming-lathes
88.
PISTON AND CONNECTING ROD FOR AN INTERNAL COMBUSTION ENGINE
The invention relates to a piston (1) of an internal combustion engine, which piston (1) has a piston head (2) with a ring field (3) and a skirt part which is arranged on the piston head (2), wherein the skirt part has at least two load-bearing skirt-wall sections (4a, 4b), and the load-bearing skirt-wall sections (4a, 4b) are connected to one another via at least two obliquely positioned box walls (5) which are set back with respect to the piston external diameter. In each case one pin boss (9) for receiving a piston pin is arranged in the box wall (5) and one skirt-wall section (4a) forms the pressure side and the other skirt-wall section (4b) forms the counter-pressure side. According to the invention that the inner surface of the pin boss (9), in relation to the piston centre, runs flushly with respect to the surface of the associated box wall (5), and the box wall (5) has a concave profile in the transverse extent with respect to the direction of the pin boss (9). Furthermore, the invention relates to a connecting rod of an internal combustion engine.
The invention relates to a cylinder liner (2) of a cylinder of an internal combustion engine, in which cylinder liner an oscillating piston (3) is guided on a running surface (4), wherein the cylinder liner (2) is fixed vertically by means of a collar (5) between a cylinder housing (1) and a cylinder head. The wet cylinder liner (2) comprises an outer side (6) which deviates from a circular shape and/or a rotationally asymmetrical outer contour of the collar (5). The cylinder liner (2) is fitted in a positionally oriented manner in a corresponding receptacle of the cylinder housing (1).
The invention relates to a method for producing a piston (1) for an internal combustion engine, which piston has at least one cooling channel (2) and is produced from at least one upper part (4) and one lower part (5), wherein the cooling channel (2) of the piston (1) is formed by means of the upper part (4) and the lower part (5) and the upper part (4) and the lower part (5) of the piston (1) are each produced by means of a forging process. According to the invention, at least one rib-like element, in particular at least one rib (9), is additionally forged during the forging of the upper part (4) in an area of the cooling channel (2) to be forged in the upper part (4) and/or at least one rib-like element, in particular at least one rib (9), is additionally forged during the forging of the lower part (5) in an area of the cooling channel (2) to be forged in the lower part (5). The invention further relates to two alternative production methods and to a piston (1) for an internal combustion engine.
A liquid cooled piston of an internal combustion engine includes a piston lower part and piston upper part which has a combustion chamber recess. These piston components are supported via joining lands which are spaced apart radially and together form a dividing plane, and are joined together with a material-to-material fit. In order to receive piston rings, the piston upper part has a ring area and includes an annular cooling channel which extends into the piston lower part and is connected to an inner cooling space via connecting channels. The cooling channel is adjoined by recesses which are oriented in the direction of a piston head, are configured as a blind hole and widen conically starting from the cooling channel as far as a recess bottom. The recess bottom can be of a pronounced undulating enlarged surface or a finely undulating configuration.
The invention relates to a method for producing a cooling-duct piston (1') for an internal combustion engine, composed of a piston upper part (2) and a piston lower part (3), wherein the piston upper part (2) is detachably connected to the piston lower part (3), and in the region between the piston upper part (2) and piston lower part (3) there is formed a cooling duct (4) which is charged with coolant via at least one inlet opening (5) during the operation of the cooling-duct piston (1, 1') and out of which coolant flows again via at least one outlet opening (14). It is provided according to the invention that, in a first method step, the piston upper part (2) is detached from the piston lower part (3), such that the piston upper part (2) is separate from the piston lower part (3), and subsequently a ring (9) which has at least one discharge opening (19), preferably at least one nozzle-shaped opening, is fastened to the inlet opening (5), and finally the piston upper part (2) and the piston lower part (3) are connected to one another again, wherein it remains possible for the cooling duct (4) to be charged with coolant via the inlet opening (5). The invention also relates to a cooling-duct piston (1') for an internal combustion engine.
The invention relates to a process for producing a piston for an internal combustion engine by casting a piston blank made of an aluminium alloy comprising aluminium (Al), magnesium (Mg) and silicon (Si), wherein the aluminium alloy has an inclusion concentration of MgAl2O4 (spinel) of less than 0.5 mm2/kg.
The invention relates to a piston (1) of an internal combustion engine, having a piston head (14) and a cooling duct (9), into which a dividing element (10) with at least one opening (13) is positioned, as a result of which a pressure chamber (11) is produced between a part of the wall of the cooling duct (9) and the separating element (10), which pressure chamber (11) is filled with pressurized oil by means of at least one oil feed line (15), wherein the oil exits from the opening (13) and impinges at least on a region of the cooling duct (9'), with the result that the piston can be cooled. According to the invention, it is provided that the non-machined separating element (10) is positioned on the wall of the later cooling duct (9), with the result that the separating element (10) can also be machined during the production of the piston (1), wherein, as a result, the machining operation of the separating element (10) which is separate from the machining operation of the piston (1) is dispensed with. Furthermore, the invention relates to a method for producing a piston (1) of this type for an internal combustion engine.
The invention relates to a method for producing a piston of an internal combustion engine and to a piston produced according to the method, comprising a piston crown (1) having annular grooves (4) and a combustion-chamber bowl (3), and a piston shaft having a pin bore for receiving a pin, wherein according to the invention both a combustion-chamber bowl rim (A) and a combustion-chamber bowl base (3) are melted and thereafter solidify.
F02B 23/06 - Other engines characterised by special shape or construction of combustion chambers to improve operation with compression ignition the combustion space being arranged in working piston
F02F 3/14 - Pistons having surface coverings on piston heads within combustion chambers
96.
PISTON SKIRT COATING CONSISTING OF A LOW-FRICTION RUNNING-IN LAYER AND A LOW-WEAR BASE LAYER
The invention relates to pistons for internal combustion engines having a skirt coating consisting of a wear-resistant inner layer consisting of a polymer matrix having ceramic particles, aramide fibres and/or carbon fibres dispersed therein and an outer layer consisting of a polymer matrix having solid lubricants dispersed therein.
F16J 1/04 - Resilient guiding parts, e.g. skirts, particularly for trunk pistons
C10M 111/04 - Lubricating compositions characterised by the base-material being a mixture of two or more compounds covered by more than one of the main groups , each of these compounds being essential at least one of them being a macromolecular organic compound
97.
METHOD FOR PRODUCING A COOLING CHANNEL SYSTEM FOR INTERNAL COMBUSTION ENGINES AND PISTON PRODUCED IN THIS WAY
The invention relates to a method for producing a cooling channel system (1) for an internal combustion engine, which has a cooling channel (4) in the piston crown (2) thereof, the piston crown (2) being adjoined by a lower piston part having a piston boss, pin bores (6) and piston skirts (5), wherein, firstly, a piston blank having a peripheral collar projecting radially in the region of the piston crown (2) is produced, wherein the collar, forming a subsequent ring zone wall (7), is then reshaped and, in a transition area (12) between the piston crown (2) and the lower piston part, a contact area for the collar is formed, and the collar is reshaped in such a way until the outer radially peripheral edge thereof comes very close to or completely into contact with the contact area in order to form a closed cooling channel (4). The invention is characterized in that, following the reshaping, the end region of the ring zone wall (7) forms a defined gap (X) with respect to the upper edge of the piston skirt (5).
The invention relates to a method for processing a constructed, liquid-cooled piston (1) of an internal combustion engine, said piston comprising an upper piston part (2) and a lower piston part (7), which are supported by means of a joining plane (10) and are connected to each other in a bonded manner. An electrochemical method, electrochemical machining, is used to produce a passage opening (12) or a hole in the piston (1). By means of said method, material is selectively removed after the completion of the upper piston part (2), the lower piston part (7), or the piston (1) after the two piston components have been joined. The electrochemical machining allows an arbitrarily geometrically designed topography having at least one passage opening (12), a hollow, or an oil pocket in cooling areas or non-cooling areas to be created on the piston (1).
The invention relates to a piston of an internal combustion engine, configured as a preferably assembled or welded liquid-cooled piston which consists of a piston lower part and a piston upper part (1) which has a combustion-chamber recess (7). These piston components are supported via joining lands (2, 3) which are spaced apart radially from one another and together form a dividing plane (4), and are joined together preferably with a material-to-material fit, preferably by means of a welded joint, or preferably frictionally, preferably by means of a screw connection. In order to receive piston rings, the piston upper part (1) comprises a ring area (10) and includes an annular cooling channel (11) which extends as far as into the piston lower part and is connected to an inner cooling space (16) via connecting channels (15). The cooling channel is adjoined by recesses (12) which are oriented in the direction of a piston head (6), are configured as a blind hole and are designed such that they are widened conically starting from the cooling channel (11) as far as a recess bottom (14) of the respective recess (12). The recess bottom (14) can be of pronounced undulating (enlarged surface) or finely undulating configuration. The piston can also be configured as a single-piece piston with a piston upper part (1) and a piston lower part without a dividing plane (4).
A piston of an internal combustion engine includes a top part produced from steel and a bottom part, which are integrally bonded in the region of a contact geometry via joining webs by a friction weld to form a structural unit. At least one cooling duct permeated by a coolant is integrated in the piston, wherein a lubricating oil of the internal combustion engine passes as the coolant into an inlet opening via a free jet of an injection nozzle, flows through the cooling duct and leaves the cooling duct via an outlet opening. For the introduction of the coolant into the cooling duct, the inlet opening is assigned a flow pipe which is inserted in the bottom part and protrudes from a cooling duct base, the opening of the flow pipe being arranged above the weld beads of the friction weld.
