阅读说明：本技术 双通道钢制活塞 (Double-channel steel piston ) 是由 爱德华多·松尾 安德鲁·莱博尔德 蒂莫西·克里斯托弗·维齐纳 迈克尔·魏内格尔 K·王 于 2018-05-16 设计创作，主要内容包括：当在内燃机中使用时,提供了一种能够在高温下操作并且因此有助于高缸内温度和降低发动机机油温的活塞。活塞包括焊接在一起的上部和下部,以在上部和下部之间提供冷却腔道。冷却腔道围绕活塞的中心轴线周向延伸并且与中心轴线间隔开。隔板位于冷却腔道中,并且从冷却腔道的一个内表面延伸到另一内表面。隔板围绕中心轴线周向延伸,并且将冷却腔道至少划分成第一通道部分和第二通道部分。隔板可以与上部或下部形成为一体。可替代地,隔板可以与上部和下部分开形成为单独的部件。(When used in an internal combustion engine, a piston is provided that is capable of operating at high temperatures and thus contributes to high in-cylinder temperatures and reduced engine oil temperatures. The piston includes upper and lower portions welded together to provide a cooling gallery between the upper and lower portions. The cooling gallery extends circumferentially about and is spaced apart from a central axis of the piston. The baffle is located in the cooling channel and extends from one inner surface of the cooling channel to the other inner surface. The baffle extends circumferentially about the central axis and divides the cooling gallery into at least a first channel portion and a second channel portion. The partition may be formed integrally with the upper or lower portion. Alternatively, the partition may be formed as a separate component separately from the upper and lower portions.)

1. A piston, comprising:

a body having an upper portion and a lower portion with a cooling channel therebetween,

the cooling channel extends circumferentially about and is spaced from a central axis of the body,

the body includes an inner surface surrounding the cooling channel, an

A baffle disposed in the cooling gallery and extending from one of the inner surfaces to the other of the inner surfaces,

the baffle extends circumferentially about the central axis, and

the partition plate divides the cooling channel into at least a first channel portion and a second channel portion.

2. The piston of claim 1, wherein the diaphragm physically separates and seals the first and second channel portions.

3. The piston of claim 1, wherein the upper portion includes an upper outer rib and an upper inner rib, the lower portion includes a lower outer rib welded to the upper outer rib at a weld, and a lower inner rib welded to the upper inner rib at a weld, and the body includes a flash positioned along the weld.

4. The piston according to claim 3, wherein the flash is located in the first channel portion, the partition physically separates and seals the first channel portion and the second channel portion, and the cooling oil is located in the second channel portion.

5. The piston of claim 3, wherein the upper rib is friction welded to the lower rib at the weld.

6. The piston according to claim 1, wherein the partition is integrally formed with the upper portion or the lower portion.

7. The piston according to claim 1, wherein the partition is formed as a separate member from the upper portion and the lower portion.

8. The piston of claim 7, wherein two of the inner surfaces include a groove and the diaphragm is disposed in the groove.

9. The piston of claim 1, wherein the diaphragm is curved from one of the inner surfaces to the other of the inner surfaces.

10. The piston of claim 1, wherein cooling oil is located in the second gallery portion and air is located in the first gallery portion.

11. The piston of claim 1, wherein

The main body is made of steel and,

the upper portion of the body includes an upper combustion wall,

the upper combustion wall has a combustion bowl surrounded by an outer rim,

said upper portion including an upper outer rib depending from said outer edge of said upper combustion wall,

the upper outer rib extends circumferentially about and is spaced from the central axis of the body,

the upper portion includes an upper inner rib depending from the upper combustion wall opposite the combustion bowl,

the upper inner rib extending circumferentially around the central axis of the body and located between the central axis of the body and the upper outer rib,

the lower portion of the body including a lower outer rib extending circumferentially about and spaced apart from the central axis of the body,

the lower outer rib is welded to the upper outer rib at an outer weld seam,

the lower portion of the body including a lower inner rib extending circumferentially about the central axis of the body and located between the central axis of the body and the lower outer rib,

the lower inner rib is welded to the upper inner rib at an inner weld,

the lower portion includes a lower wall between the lower outer rib and the lower inner rib,

the upper combustion wall including an upper inner surface between the upper outer rib and the upper inner rib, the lower wall including a lower inner surface, the inner rib having a first inner surface, and the outer rib having a second inner surface,

the inner surface faces and surrounds the cooling channel, and

the body includes a flash located proximate the weld.

12. The piston of claim 11, wherein the lower portion of the body includes a skirt depending from the lower outer rib and circumferentially spaced from one another by pin bosses, and each of the pin bosses has a pin bore.

13. The piston of claim 11, wherein

The baffle being integrally formed with the lower wall and extending upwardly from the lower wall to a distal end at or near the upper inner surface of the upper combustion wall such that the first channel portion is located between the baffle and the inner rib and the second channel portion is located between the outer rib and the baffle,

the volume of the second channel portion is greater than the volume of the first channel portion,

the separator has a cylindrical shape and is formed with a cylindrical shape,

the flash being located in the first channel portion along the first weld and being physically separated from the second channel portion by the partition,

the second passage portion contains cooling oil, and

the first channel portion contains air.

14. The piston of claim 11, wherein

The baffle being integrally formed with the lower wall, the baffle extending upwardly from the lower wall and being bent to a distal end at or near the first inner surface of the upper inner rib such that the first channel portion is located between the baffle, a portion of the inner rib and a portion of the lower wall,

the volume of the second channel portion is greater than the volume of the first channel portion,

the weld bead is positioned along the first weld in the first channel portion and is physically separated from the second channel portion by the separator,

the lower body includes an oil inlet to the second channel portion,

the second passage portion contains cooling oil, and

the first channel portion is sealed and contains air.

15. The piston of claim 1, wherein

The baffle being integrally formed with the lower outer rib, the baffle extending horizontally from the lower outer rib to a distal end at or near the first inner surface of the upper inner rib,

said first channel portion being located between said baffle plate and an upper inner surface of said upper combustion wall, said second channel portion being located between said baffle plate and said lower inner surface of said lower wall,

the fly edge is positioned along the second weld in the first channel portion and is physically separated from the second channel portion by the baffle,

the lower portion of the body includes an oil inlet to the second passage portion,

the second passage portion contains cooling oil, and

the first channel portion is sealed and contains air.

16. The piston of claim 11, wherein

The first inner surface of the upper inner rib includes a first groove, the second inner surface of the upper outer rib includes a second groove horizontally aligned with the first groove,

the partition is an annular member separate from the body, the partition extending horizontally from the first groove to the second groove,

said first channel portion being located between said baffle plate and said upper inner surface of said upper combustion wall and said second channel portion being located between said baffle plate and said lower inner surface of said lower wall,

the second channel portion including a weld bead between the ribs, the weld bead being physically separated from the first channel portion by the separator,

the lower portion of the body includes an oil inlet to the second passage portion,

the second passage portion contains cooling oil, and

the first channel portion is sealed and contains air.

17. A method of manufacturing a piston, comprising the steps of:

connecting an upper portion of a body to a lower portion of the body to form a cooling gallery therebetween, the cooling gallery extending circumferentially about and spaced apart from a central axis of the body, the body including an inner wall surface surrounding the cooling gallery, the body including a partition disposed in the cooling gallery and extending from one of the inner surfaces to the other of the inner surfaces, the partition extending circumferentially about the central axis and dividing the cooling gallery into at least a first channel portion and a second channel portion.

18. The method of claim 17, wherein the connecting step comprises friction welding the upper portion to the lower portion.

19. The method of claim 17, wherein the bulkhead is a separate component from the upper portion and the lower portion, and the method includes disposing the bulkhead between the inner wall surfaces prior to joining the upper portion to the lower portion.

20. The method of claim 17, wherein the baffle is integrally formed with the upper portion or the lower portion.

1. Field of the invention

The present invention generally relates to pistons for internal combustion engines and methods for manufacturing pistons.

Background

Disclosure of Invention

One aspect of the present invention includes a piston for an internal combustion engine that is capable of performing well during operation. The piston includes a body having an upper portion and a lower portion with a cooling gallery therebetween. The cooling gallery extends circumferentially about and is spaced apart from a central axis of the body. The body includes an inner wall surface surrounding the cooling channel, and the body includes a baffle disposed in the cooling channel and extending from one inner surface to the other inner surface. The baffle extends circumferentially about the central axis, and the baffle divides the cooling gallery into at least a first passage portion and a second passage portion.

Another aspect of the invention provides a method of manufacturing a piston. The method includes the step of connecting an upper portion of the body to a lower portion of the body to form a cooling channel between the upper and lower portions. The cooling gallery extends circumferentially about and is spaced apart from a central axis of the body. The body includes an inner wall surface surrounding the cooling channel. The body also includes a baffle disposed in the cooling gallery and extending from one of the inner surfaces to the other inner surface. The baffle extends circumferentially about the central axis, and the baffle divides the cooling gallery into at least a first channel portion and a second channel portion.

Brief description of the drawings

Other advantages of the present invention will be readily appreciated, as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings wherein:

FIG. 1 is a side cross-sectional view of a piston including a baffle in a cooling gallery according to an exemplary embodiment;

FIG. 2 is an enlarged view of a cooling gallery of the piston of FIG. 1;

FIG. 3 is an enlarged view of a portion of a piston including a partition in a cooling gallery according to a second exemplary embodiment;

FIG. 4 is an enlarged view of a portion of a piston including a partition in a cooling gallery according to a third exemplary embodiment; and

FIG. 5 is an enlarged view of a portion of a piston including a partition in a cooling gallery according to a fourth exemplary embodiment.

Detailed Description

One aspect of the present invention is a piston 10 that is capable of operating at high temperatures when used in an internal combustion engine and thus contributes to high in-cylinder temperatures and reduces engine oil temperatures. An example of a piston 10 is shown in fig. 1, but many other designs are possible.

As shown in FIG. 1, the piston 10 includes a body 12, the body 12 having an upper portion 14 and a lower portion 16 with a cooling gallery 18 between the upper and lower portions 14, 16. The upper and lower portions 14, 16, respectively, of the body 12 are formed of steel. In the exemplary embodiment, upper portion 14 includes an upper combustion wall 20, and upper combustion wall 20 presents a combustion bowl surrounded by an outer rim. The upper portion 14 also includes an upper outer rib 22 depending from an outer edge of the upper combustion wall 20, and an upper inner rib 24 depending from the upper combustion wall 20 opposite the combustion bowl. The upper outer rib 22 extends circumferentially about the central axis a of the body 12 and is spaced from the central axis a of the body 12. The upper inner rib 24 extends circumferentially about the central axis a of the body 12 and is located between the central axis a of the body 12 and the upper outer rib 22.

In the exemplary embodiment, lower portion 16 of body 12 includes a lower outer rib 26 and a lower inner rib 28, lower outer rib 26 extending circumferentially about a central axis a of body 12 and spaced apart from a central axis a of body 12, and lower inner rib 28 extending circumferentially about central axis a of body 12 and located between central axis a of body 12 and lower outer rib 26. The lower outer rib 26 is welded to the upper outer rib 22 at an outer weld 30 and the lower inner rib 28 is welded to the upper inner rib 24 at an inner weld 32. The welds 30, 32 extend circumferentially about the central axis a of the piston 10. The body 12 includes a flash 34 in the form of a weld bead located adjacent the weld 30, 32. The flash 34 is formed during the welding process, which is typically a friction welding process. Lower portion 16 also includes a lower wall 36 located between lower outer rib 26 and lower inner rib 28. In the exemplary embodiment of fig. 1, the lower portion 16 of the body 12 includes a skirt 38, the skirts 38 depending from the lower outer rib 26 and being circumferentially spaced from one another by pin bosses 40, and each pin boss 40 having a pin bore.

As shown in fig. 2-5, the upper combustion wall 20 includes an upper inner surface 42 located between the upper outer rib 22 and the upper inner rib 24, the lower wall 36 includes a lower inner surface 44, the inner ribs 24, 28 have a first inner surface 46, and the outer ribs 22, 26 have a second inner surface 48. The inner surfaces 42, 44, 46, 48 face and surround the cooling gallery 18. The cooling gallery 18 extends circumferentially about and is spaced from the central axis a of the body 12.

As shown in fig. 1-5, and particularly in fig. 2-5, the piston 10 further includes a partition 50 disposed in the cooling gallery 18 and extending from one of the inner surfaces 42, 44, 46, 48 to another of the inner surfaces 42, 44, 46, 48. The partition 50 extends circumferentially about the central axis A and divides the cooling gallery 18 into at least a first channel portion 52 and a second channel portion 54. For example, the partitions 50 may divide the cooling gallery 18 vertically, horizontally, at an angle, or otherwise. In the exemplary embodiment, a spacer 50 protrudes into channel 18 from one inner surface 42, 44, 46, 48 and terminates at the other inner surface 42, 44, 46, 48 to physically separate and separate at least one weld 30 or 32 in a first channel portion 52 from a remaining second channel portion 54.

In the exemplary embodiment, a partition 50 seals first channel portion 52 and separates first channel portion 52 from second channel portion 54. The first channel portion 52 contains air or another insulating medium for insulation, and the second channel portion 54 contains cooling oil. The partition 50 physically separates the inner weld 32 located in the first channel portion 52 from the cooling oil. In some embodiments, the baffle 50 is integrally formed with the upper portion 14 or the lower portion 16. Alternatively, the baffle 50 may be formed as a separate component from the upper and lower portions 14, 16. For example, two of the inner surfaces 42, 44, 46, 48 may include a groove 56, and the baffle 50 may be disposed in the groove 56. In this case, the partition 50 may be a plate spanning the length of the cooling gallery 18 and inserted into the upper or lower portion 14, 16 of the body 12 prior to welding. The plate remains within the cooling gallery 18 after welding to divide the cooling gallery 18 into two parts.

The baffle 50 may extend directly from one of the interior surfaces 42, 44, 46, 48 to another of the interior surfaces 42, 44, 46, 48, or the baffle 50 may curve from one of the interior surfaces 42, 44, 46, 48 to another of the interior surfaces 42, 44, 46, 48. The partition 50 may extend from the lower portion 14 to the upper portion 16 of the body 12 and vice versa. Alternatively, the baffle 50 may extend from one of the inner surfaces 42, 44, 46, 48 of the upper portion 14 to another of the inner surfaces 42, 44, 46, 48 of the upper portion 14. The baffle 50 may also extend from one of the inner surfaces 42, 44, 46, 48 of the lower portion 16 to another of the inner surfaces 42, 44, 46, 48 of the lower portion 16.

In the exemplary embodiment of fig. 1 and 2, the baffle 50 is integrally formed with the lower wall 36 and extends straight upward from the lower wall 36 to a distal end 58 at the upper inner surface 42 of the upper combustion wall 20. The partition 50 has a cylindrical shape extending circumferentially around the central axis a of the body 12. In this embodiment, the distal end 58 of the baffle 50 contacts or engages the upper interior surface 42. Alternatively, distal end 58 may be generally in contact with upper inner surface 42, i.e., located adjacent upper inner surface 42. The first channel portion 52 is located between the partition 50 and the inner ribs 24, 28, and the second channel portion 54 is located between the outer ribs 22, 26 and the partition 50. The first channel portion 52 is located radially inward of the second channel portion 54. The first channel portion 52 and the second channel portion 54 each have a volume, the volume of the second channel portion 54 being greater than the volume of the first channel portion 52. The weld bead located along the interior weld 32 in the first channel portion 52 is physically isolated from the second channel portion 54 by the partition 50. The first channel portion 52 is sealed and contains air. The lower portion 16 of the body includes an oil inlet 60 that opens into the second passage portion 54, and the second passage portion 54 contains cooling oil. Any strips or other portions of the weld bead that may form near the inner weld bead 32 will be contained in the first channel portion 52 and will not be exposed to the cooling oil in the second channel portion 54.

In the exemplary embodiment of fig. 3, the baffle 50 is formed integrally or as one piece with the lower wall 36 and extends upwardly from the lower wall 36. In this case, the baffle 50 is bent at the first inner surface 46 of the upper inner rib 24 to the distal end 58. More specifically, the partition 50 has a dome shape (inverted J-shaped cross-section) that terminates in a radially inward circumferential surface that overlies the first weld 32 and engages or is closely spaced from the first inner surface 46 of the upper inner rib 24 such that the first weld 32 is captured within a first channel portion 52 defined by the relatively small space between the partition 50 and the inner ribs 24, 28, and a second channel portion 54 is defined by the remainder of the cooling gallery 18. In this embodiment of fig. 3, the distal end 58 of the baffle 50 contacts or engages the first inner surface 46. Alternatively, the distal end 58 may substantially contact the first inner surface 46, i.e., be located adjacent the first inner surface 46. The first channel portion 52 is located between the partition 50 and a portion of the inner ribs 24, 28 and a portion of the lower wall 36. The embodiment of FIG. 3 serves to maximize the surface of the second channel 54 exposed to the cooling oil while maintaining physical separation of the oil from the flash 34 adjacent the inner weld 32, which inner weld 32 is captured and completely contained within the first channel portion 52. The volume of the second channel portion 54 is greater than the volume of the first channel portion 52. The flash 34 in the form of a weld bead located along the inner weld 32 in the first channel portion 52 is physically separated from the second channel portion 54 by the partition 50. The first channel portion 52 is sealed and contains air. The lower portion 16 of the body 12 includes an oil inlet 60 that opens into the second channel portion 54, and the second channel portion 54 contains cooling oil. In the exemplary embodiment of fig. 4, the baffle 50 is integrally formed with the lower outer rib 26 and extends horizontally from the lower outer rib 26 to a distal end 58 at the first inner surface 46 of the upper inner rib 24. In this embodiment, the distal end 58 of the baffle 50 contacts or engages the first inner surface 46. Alternatively, the distal end 58 may substantially contact the first inner surface 46, i.e., be located adjacent the first inner surface 46. The first channel portion 52 is located between the partition 50 and the upper interior surface 42 of the upper combustion wall 20, and the second channel portion 54 is located between the partition 50 and the lower interior surface 44 of the lower wall 36. The diaphragm 50 locates the outer weld 30 and the flash 34 in the upper first channel portion 52 and the inner weld 32 and the flash 34 in the lower second channel portion 54. The partition 50 prevents the cooling oil of the second passage portion 52 from entering the first passage portion 52 of the upper portion. The flash 34 is positioned along the interior weld 32 in the first channel portion 52 and is physically separated from the second channel portion 54 by the partition 50. The first channel portion 52 is sealed and contains air. The lower portion 16 of the body 12 includes an oil inlet 60 that opens into the second passage portion 54, and the second passage portion 54 contains cooling oil.

In the exemplary embodiment of fig. 5, the diaphragm 50 is an annular member formed separately from the body 12 of the piston 10. The first inner surface 46 of the upper inner rib 24 includes a first groove 56 and the second inner surface 48 of the upper outer rib 22 includes a second groove 56 that is horizontally aligned with the first groove 56. The partition 50 extends horizontally from the first groove 56 to the second groove 56. The first channel portion 52 is located between the partition 50 and the upper interior surface 42 of the upper combustion wall 20, and the second channel portion 54 is located between the partition 50 and the lower interior surface 44 of the lower wall 36. The second channel portion 54 includes a weld bead between the upper and lower ribs 22, 24, 26, 28 that is physically separated from the first channel portion 52 by the partition 50. The first channel portion 52 is sealed and contains air. The lower portion 16 of the body 12 includes an oil inlet opening into the second channel portion 54, and the second channel portion 54 contains cooling oil.

Another aspect of the invention provides a method of manufacturing a piston. The method includes connecting an upper portion of a body to a lower portion of the body to form a cooling channel between the upper and lower portions. According to an exemplary embodiment, the method includes first forming the upper portion of the body and the lower portion of the body separately. The partition plate may be integrally formed with the upper or lower portion of the body. For example, the bulkhead may be machined in the lower portion of the body or in the upper portion of the body before welding the upper portion to the lower portion. Alternatively, the partition may be formed as a separate component from the body, and the partition may be disposed between the inner wall surfaces prior to joining the upper portion to the lower portion. The step of joining includes welding the upper rib to the lower rib, such as by friction welding. The welding step forms a weld bead in the vicinity of the weld of the steel material of the body.

The baffles in the cooling channels may provide several advantages. The barrier may prevent the welding rod (i.e., the metal strip produced during friction welding) from entering the engine oil by enclosing at least one weld, and thus, the weld curls into one of the channel portions isolated from the engine oil. For example, the weld and weld bead may be located only in the first channel portion, and engine oil may be located in the second channel portion, which does not include the weld bead.

Dividing the cooling gallery into two or more distinct channel portions, such as an oil cooled region and an air filled (non-oil cooled) region, may provide a number of other benefits. First, certain engine designs/applications perform better under high in-cylinder temperature conditions. By leaving an insulating air gap at the top of the piston, the piston temperature, and hence the in-cylinder temperature, will become hot. The air acts as an insulator and therefore the air gap contributes more to increasing the piston temperature than if this region were filled with steel. The mass of the piston contained in the channel portion is also relatively reduced. When the first channel portion is located at the top of the piston and contains air, the second channel portion located at the lower portion of the piston may be used as a typical piston channel, having an oil inlet and an oil outlet. This will help to balance the piston temperature so that the temperature does not exceed the steel working boundary temperature. In addition, this lower second passage portion of the cooling gallery will reduce the temperature of the pin bore and skirt portion as compared to a cooling gallery that is completely filled with air. This is important for the frictional properties of these interfaces.

Second, the use of a partition in the piston body may improve the life of engine oil even if high in-cylinder temperatures are not favorable. If oil is held in the lower gallery and thus away from the hottest portions of the piston (e.g., the upper combustion wall and bowl rim of the piston), the rise in oil temperature in the cooling gallery may be reduced. The lower engine oil operating temperature prevents degradation or oxidation of the engine oil and extends the life of the engine oil. It also reduces the accumulation of carbon in the cooling gallery (i.e., combustion oil that adheres to the inner walls).

It will be appreciated that in any of the above embodiments, the partitions may extend at an angle through the channels or be non-planar in shape, and additional partitions may be provided to divide the channels into more than two spaces (3 or more), and the additional partitions may isolate the inner and outer welds from the portions of the channels carrying the cooling oil.

Obviously, many modifications and variations of the present invention are possible in light of the above teachings, and the invention may be practiced otherwise than as specifically described within the scope of the appended claims. In particular, all features of all claims and all embodiments can be combined with each other as long as they are not mutually contradictory.