CN116971887A - Lightweight structure of high-strength diesel engine steel piston - Google Patents
Lightweight structure of high-strength diesel engine steel piston Download PDFInfo
- Publication number
- CN116971887A CN116971887A CN202310823923.6A CN202310823923A CN116971887A CN 116971887 A CN116971887 A CN 116971887A CN 202310823923 A CN202310823923 A CN 202310823923A CN 116971887 A CN116971887 A CN 116971887A
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- CN
- China
- Prior art keywords
- steel piston
- lightweight
- head
- rib
- piston
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 229910000831 Steel Inorganic materials 0.000 title claims abstract description 80
- 239000010959 steel Substances 0.000 title claims abstract description 80
- 238000002485 combustion reaction Methods 0.000 claims abstract description 13
- 238000001816 cooling Methods 0.000 claims abstract description 12
- 230000007704 transition Effects 0.000 claims description 3
- 239000013585 weight reducing agent Substances 0.000 description 11
- 239000000463 material Substances 0.000 description 8
- 229910000838 Al alloy Inorganic materials 0.000 description 4
- 229910001208 Crucible steel Inorganic materials 0.000 description 3
- 238000000034 method Methods 0.000 description 3
- 238000011161 development Methods 0.000 description 2
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 1
- 229910052782 aluminium Inorganic materials 0.000 description 1
- 238000013459 approach Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 239000012530 fluid Substances 0.000 description 1
- 235000013372 meat Nutrition 0.000 description 1
- 238000005457 optimization Methods 0.000 description 1
- 230000002787 reinforcement Effects 0.000 description 1
- 238000012546 transfer Methods 0.000 description 1
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02F—CYLINDERS, PISTONS OR CASINGS, FOR COMBUSTION ENGINES; ARRANGEMENTS OF SEALINGS IN COMBUSTION ENGINES
- F02F3/00—Pistons
- F02F3/28—Other pistons with specially-shaped head
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02F—CYLINDERS, PISTONS OR CASINGS, FOR COMBUSTION ENGINES; ARRANGEMENTS OF SEALINGS IN COMBUSTION ENGINES
- F02F3/00—Pistons
- F02F3/0015—Multi-part pistons
- F02F3/0069—Multi-part pistons the crown and skirt being interconnected by the gudgeon pin
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02F—CYLINDERS, PISTONS OR CASINGS, FOR COMBUSTION ENGINES; ARRANGEMENTS OF SEALINGS IN COMBUSTION ENGINES
- F02F3/00—Pistons
- F02F3/0076—Pistons the inside of the pistons being provided with ribs or fins
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02F—CYLINDERS, PISTONS OR CASINGS, FOR COMBUSTION ENGINES; ARRANGEMENTS OF SEALINGS IN COMBUSTION ENGINES
- F02F3/00—Pistons
- F02F3/16—Pistons having cooling means
Landscapes
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Pistons, Piston Rings, And Cylinders (AREA)
Abstract
The invention relates to a lightweight structure of a high-strength diesel engine steel piston, which is provided with a head (1), and comprises a lightweight head (1), a lightweight pin hole (2) and a lightweight skirt (3); the head (1) comprises a steel piston inner cooling oil cavity (13), and annular weight-reducing cavities are arranged at the fire land (8), the second ring land (9), the third ring land (10), the lower edge (11) of the third ring groove and the lower area (12) of the bottom ring of the combustion chamber; the pin hole (2) is connected with the head (1) through a first rib (4) and a second rib (5); the skirt (3) is connected with the pin hole (2) through a rib third (6); the skirt (3) is connected to the head (1) by a fourth rib (7). The lightweight structure of the invention can systematically lighten the head structure, the pin boss structure and the skirt structure of the steel piston of the diesel engine, and reduce the weight of the steel piston to be within an acceptable range.
Description
Technical Field
The invention relates to an engine piston, in particular to a lightweight structure of a high-strength diesel engine steel piston, and specifically relates to a lightweight structure of a head part, a pin boss and a skirt part of the steel piston.
Background
In order to meet the requirements of the diesel engine on continuous development of high reinforcement, light weight, compactness, low emission and the like, the steel piston gradually replaces the traditional aluminum alloy piston by virtue of the self-high strength material, and becomes the first choice of the high-reinforcement diesel engine piston. However, the steel material density is higher than that of aluminum alloy, if the steel piston is designed according to the structure and the size of the existing aluminum alloy piston, the weight of the steel piston is increased by 1.9 times, the reciprocating inertia force of the piston is greatly increased, the dynamic performance of the piston, the balance of the whole machine and the vibration impact are influenced, and the reliability of engine parts is further influenced. Therefore, how to realize the light-weight design of the steel piston structure is a key for improving the autonomous development level of the domestic high-strength diesel engine steel piston.
Chinese patent CN 102979641A discloses an integral cast steel piston, in which a face window type weight-reducing region is provided on the skirt portion of the piston, the integral cast steel piston reduces the weight by 15% -20% or more, so that the weight of the integral cast steel piston approaches the weight of the same type of aluminum alloy piston, and the requirement of engine weight reduction is satisfied. The ring groove area and the skirt part are provided with an annular cavity, the direction of a pin hole on the piston skirt part is provided with a face window type weight-reducing area, the weight-reducing structure is used for simply removing materials inwards on the basis of the original structure, the topological structure of the weight-reducing structure is not changed, and a large amount of weight-reducing space is reserved for the steel piston. Chinese patent CN 107313873A discloses a lightweight piston, which adopts an asymmetric piston structure, and performs fleshing treatment on the upper end of the outer pin seat, so as to more space the upper end of the outer pin seat, and thin the window. Although the patent can realize the light weight of the piston, the piston structure shown in the patent is not provided with an internal cooling oil cavity structure, so that the piston still has a large amount of space for weight reduction, and the piston without the internal cooling oil cavity structure can bear larger heat load, thereby influencing the service life of the piston. Chinese patent CN 114165353A discloses a lightweight piston, comprising a piston body, wherein the piston body is provided with a piston head and a piston skirt, the piston head is provided with an annular oil cavity, and the piston skirt and/or the piston head is provided with an annular weight-reducing cavity. The oil passing hole for communicating the annular oil cavity and the annular weight reduction cavity is formed in the annular plate, the oil cavity structure is essentially the structure of the oil cavity, the weight can be further reduced compared with the structure without the oil cavity structure, and the structure can influence the oscillating flow and heat transfer of fluid in the oil cavity, so that the oil cavity structure is not lost. Chinese patent CN 202970934U discloses a novel gasoline engine light-weight internal cooling insert piston, the upper part of the face window of the piston body is designed with a weight-reducing cavity, the weight-reducing structure is to simply remove materials inwards on the basis of the original structure, the topology structure is not changed, and the steel piston still has a lot of space for weight reduction. Chinese patent CN 215292702U discloses a lightweight piston with an arch skirt, a lightweight arc structure with an indent in arch is arranged outside a piston pin seat, the weight reduction structure is to simply remove materials inwards on the basis of the original structure, the topology structure is not changed, and a large amount of space is still available for weight reduction of the steel piston. Chinese patent CN 217270508U discloses a lightweight piston, although this structure can lighten the weight of piston, but also sacrifice the prerequisite of not having interior cold oil chamber cooling function, and the scheme of losing weight is too loaded down with trivial details, and the piston still has the space of losing weight simultaneously. Chinese patent CN 218581707U discloses an M-type lightweight piston and engine, through reducing the thickness of the lower end of the piston window, makes the lower end cross section of the piston window form the M-type, so as to lighten the overall weight of the piston, and the weight-reducing structure is based on the original structure and is used for simply removing materials inwards, and the topology structure is not changed, and the steel piston still has a lot of space capable of reducing weight.
In summary, the weight reduction of the steel piston structure is mainly focused on the meat removal treatment of the steel piston structure, and although the weight of the steel piston can be reduced to a certain extent, the topology structure of the steel piston is not changed, and a large amount of weight reduction space is reserved for the steel piston. Compared with aluminum materials, the steel materials have larger density, and the problem of light weight is difficult to effectively solve, so that the weight reduction of the steel piston structure is particularly important.
At present, the weight optimization of the steel piston structure mainly has the following defects:
1) The key areas of the steel piston are not systematically lightened;
2) The weight of the steel piston is still not within an acceptable range.
Disclosure of Invention
The invention provides a light-weight structure of a high-strength diesel engine steel piston, aiming at the problems existing in the prior art.
In order to solve the technical problems, the invention is realized by adopting the following technical scheme:
a lightweight structure of a high-strength diesel engine steel piston is provided, wherein the high-strength diesel engine steel piston is provided with a head part, and the lightweight structure comprises a lightweight head part, a lightweight pin hole and a lightweight skirt part; the head part comprises a steel piston inner cooling oil cavity, an annular weight-reducing cavity is arranged at the lower edges of a fire power bank, a second ring bank, a third ring bank and a third ring groove and the lower region of a bottom ring of the combustion chamber, and the cross section of the annular weight-reducing cavity is a closed region formed by curves at will; the annular weight-reducing cavity is not communicated with the inner cooling oil cavity; the pin hole is connected with the head part through a first rib and a second rib, the plane where the first rib is positioned is parallel to the direction of the pin hole, and the plane where the second rib is positioned is perpendicular to the direction of the pin hole; the skirt is connected with the pin hole by the third rib and the head by the fourth rib; the projection shape of the skirt part is a closed section formed by curves at will, and the range of the height direction of the projection shape of the skirt part does not exceed the bottom and the top of the height direction of the projection shape of the pin hole.
Further, the number of the annular weight-reducing cavities is greater than 1.
Further, the cross section of the annular weight-reducing cavity is a closed section formed by a circular curve, an arbitrary polygon curve or an elliptic curve.
Further, the shortest distance between any position of the cross section of the annular weight-reducing cavity and any position of the cross section of the steel piston is not less than 1mm.
Further, the lower region of the combustion chamber bottom ring comprises a transition region from the combustion chamber bottom to the top of the steel piston inner chamber.
Further, the number of the first ribs is not less than 2.
Further, the number of the second ribs is an even number greater than 2 and is distributed in a pair.
Further, the projection shape of the skirt part comprises a closed section formed by a round, any polygonal or elliptic curve.
Further, the number of the fourth ribs is not less than 2.
Further, the number of the third ribs is greater than 1.
The invention has the beneficial effects that:
the steel piston lightweight structure of the diesel engine can systematically lighten the head structure, the pin boss structure and the skirt structure of the steel piston of the diesel engine, and reduce the weight of the steel piston to be within an acceptable range, and specifically comprises the following components:
(1) The invention discloses a lightweight steel piston head, which is characterized in that the weight of a steel piston head area is reduced by an annular weight reduction cavity on the premise of retaining the structure of a cold oil cavity in the steel piston, the position of the annular weight reduction cavity does not influence the functions of key areas such as a steel piston combustion chamber, a ring land, a ring groove and the like, and the head is lightweight on the premise of ensuring that the steel piston head has good cooling performance;
(2) The invention discloses a lightweight steel piston pin seat, which is characterized in that the head of a steel piston is connected with a pin hole through ribs on the premise of retaining the pin hole structure contacted with a piston pin, and the topological structure of the steel piston pin seat is changed by the method, so that the lightweight of the steel piston pin seat structure is realized;
(3) The light-weight steel piston skirt part is characterized in that the skirt part structure is not directly connected with the steel piston head part, but is connected with the steel piston head part through ribs, the skirt part structure is reduced to the minimum on the premise of ensuring that the piston can reciprocate in a cylinder to play a guiding role and bear lateral pressure, and the method changes the topological structure of the steel piston skirt part, so that the light-weight of the steel piston skirt part structure is realized;
(4) Compared with an unchanged steel piston, the steel piston adopting the light-weight structure can reduce the weight by 40% at most.
Drawings
The invention is further described below with reference to the accompanying drawings:
FIG. 1 is a right three-axis view of a steel piston;
FIG. 2 is a schematic view of a steel piston in a vertical pin bore direction;
FIG. 3 is a schematic view of a parallel pin bore of a steel piston;
FIG. 4 is a cross-sectional view of a steel piston of the present invention taken in a vertical pin bore direction;
FIG. 5 is a cross-sectional view of a steel piston of the present invention in a parallel pin bore direction;
FIG. 6 is a schematic view showing the relationship between the plane of the first rib and the second rib and the direction of the pin hole;
the reference numerals in the figures are: 1-head, 2-pin hole, 3-skirt, 4-first rib, 5-second rib, 6-third rib, 7-fourth rib, 8-fire bank, 9-second ring bank, 10-third ring bank, 11-third ring groove lower edge, 12-combustion chamber bottom ring lower region, 13-steel piston inner cooling oil pocket.
Detailed Description
The following describes in detail the examples of the present invention, which are implemented on the premise of the technical solution of the present invention, and detailed embodiments and specific operation procedures are given, but the scope of protection of the present invention is not limited to the following examples.
Referring to fig. 1 to 3, a description will be given below of a certain diesel engine steel piston lightweight structure as an example, in which the lightweight of a highly reinforced diesel engine steel piston is achieved by the following structure:
1) Lightweight head structure
As shown in fig. 4-5, the weight reducing cavity is formed in an open loop shape at the fire land 8, the second land 9, the third land 10, the third annular lower edge 11 and the lower area 12 of the bottom ring of the combustion chamber on the premise of retaining the structure of the cold oil cavity 13 in the steel piston, and the lower area 12 of the bottom ring of the combustion chamber comprises but is not limited to a transition area from the bottom of the combustion chamber to the top of the inner cavity of the steel piston.
The annular weight-reducing cavities are not communicated with the internal cooling oil cavity, and the number of the annular weight-reducing cavities arranged at the fire land 8, the second ring land 9, the third ring land 10, the third ring groove lower edge 11 and the combustion chamber bottom ring lower area 12 is not less than 1.
The cross section of the annular weight-reducing cavity can be a closed section formed by curves at will, and the section of the annular weight-reducing cavity comprises a circle, any polygon, an ellipse and the like, and the shortest distance between the position of any part of the cross section and the position of any part of the cross section of the steel piston is not less than 1mm.
2) Light pin base structure
As shown in fig. 4 to 5, the pin hole 2 is connected to the head portion 1 by the first rib 4 and the second rib 5, the plane where the pin hole 2 and the first rib 4 of the head portion 1 are connected is parallel to the pin hole direction of the steel piston, and the number of the ribs is not less than 2.
The plane of the connecting pin hole 2 and the second rib 5 of the head part 1 is perpendicular to the direction of the steel piston pin hole, and the number of the ribs is even and not less than 2 and is distributed in a pair.
3) Lightweight skirt structure
As shown in fig. 4 to 5, the skirt 3 is connected to the pin hole 2 by a third rib 6, and a fourth rib 7 is connected to the head 1; the number of fourth ribs 7 connecting the skirt 2 and the head 1 is not less than 2; the number of the third ribs 6 connecting the skirt portion 3 and the pin hole 2 is not less than 1.
The projection shape of the skirt portion 3 may be a closed section formed by a curve at will, including a circle, an arbitrary polygon, an ellipse, etc., and the range of the projection shape of the skirt portion 3 in the height direction must not exceed the bottom and the top of the projection shape of the pin hole 2 in the height direction.
Claims (10)
1. The utility model provides a lightweight structure of high-strength diesel engine steel piston, this high-strength diesel engine steel piston is last to have head (1), its characterized in that:
the lightweight structure comprises a lightweight head (1), a lightweight pin hole (2) and a lightweight skirt (3);
the head (1) comprises a steel piston inner cooling oil cavity (13), and annular weight-reducing cavities are arranged at the positions of a fire land (8), a second ring land (9), a third ring land (10), a third ring groove lower edge (11) and a combustion chamber bottom ring lower area (12), wherein the cross section of each annular weight-reducing cavity is a closed section formed by curves at will; the annular weight-reducing cavity is not communicated with the inner cooling oil cavity;
the pin hole (2) is connected with the head (1) through a first rib (4) and a second rib (5), the plane where the first rib (4) is positioned is parallel to the direction of the pin hole (2), and the plane where the second rib (5) is positioned is perpendicular to the direction of the pin hole (2);
the skirt (3) is connected with the pin hole (2) by a third rib (6) and is connected with the head (1) by a fourth rib (7); the projection shape of the skirt part (3) is a closed section formed by curves at will, and the range of the height direction of the projection shape of the skirt part (3) is not beyond the bottom and the top of the height direction of the projection shape of the pin hole (2).
2. The steel piston lightweight structure of claim 1, wherein:
the number of the annular weight-reducing cavities is greater than 1.
3. The steel piston lightweight structure of claim 1, wherein:
the cross section of the annular weight-reducing cavity is a closed section formed by a circular curve, any polygon or an elliptic curve.
4. The steel piston lightweight structure of claim 1, wherein:
the shortest distance between any position of the cross section of the annular weight-reducing cavity and any position of the cross section of the steel piston is not less than 1mm.
5. The steel piston lightweight structure of claim 1, wherein:
the lower region (12) of the combustion chamber bottom ring comprises a transition region from the combustion chamber bottom to the top of the steel piston inner chamber.
6. The steel piston lightweight structure of claim 1, wherein:
the number of the first ribs (4) is not less than 2.
7. The steel piston lightweight structure of claim 1, wherein:
the number of second ribs (5) is an even number greater than 2 and is distributed in pairs.
8. The steel piston lightweight structure of claim 1, wherein:
the projection shape of the skirt (3) comprises a closed section formed by a round, arbitrary polygon or elliptic curve.
9. A steel piston lightweight structure as claimed in any one of claims 1 to 8, wherein:
the number of the fourth ribs (7) is not less than 2.
10. A steel piston lightweight structure as claimed in any one of claims 1 to 8, wherein:
the number of the third ribs (6) is more than 1.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310823923.6A CN116971887B (en) | 2023-07-06 | 2023-07-06 | Lightweight structure of high-strength diesel engine steel piston |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310823923.6A CN116971887B (en) | 2023-07-06 | 2023-07-06 | Lightweight structure of high-strength diesel engine steel piston |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN116971887A true CN116971887A (en) | 2023-10-31 |
| CN116971887B CN116971887B (en) | 2024-02-23 |
Family
ID=88470479
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202310823923.6A Active CN116971887B (en) | 2023-07-06 | 2023-07-06 | Lightweight structure of high-strength diesel engine steel piston |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN116971887B (en) |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB303531A (en) * | 1927-07-06 | 1929-01-07 | Adolph Lincoln Nelson | Improvements in pistons |
| CH237068A (en) * | 1942-04-04 | 1945-03-31 | Gmbh Karl Schmidt | Light metal pistons on internal combustion engines, with one-sided resilient sliding shoe. |
| JPH10288083A (en) * | 1997-04-10 | 1998-10-27 | Unisia Jecs Corp | Piston for internal combustion engine |
| US20100101527A1 (en) * | 2007-04-21 | 2010-04-29 | Ks Kolbenschmidt Gmbh | Load-optimized interior of a piston |
| CN201679576U (en) * | 2010-03-30 | 2010-12-22 | 山东滨州渤海活塞股份有限公司 | Integral aluminium-alloy piston bearing explosion pressure of 20MPa and having inner-cooling structure |
| CN217270508U (en) * | 2022-02-16 | 2022-08-23 | 山东双港活塞股份有限公司 | Lightweight piston |
-
2023
- 2023-07-06 CN CN202310823923.6A patent/CN116971887B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB303531A (en) * | 1927-07-06 | 1929-01-07 | Adolph Lincoln Nelson | Improvements in pistons |
| CH237068A (en) * | 1942-04-04 | 1945-03-31 | Gmbh Karl Schmidt | Light metal pistons on internal combustion engines, with one-sided resilient sliding shoe. |
| JPH10288083A (en) * | 1997-04-10 | 1998-10-27 | Unisia Jecs Corp | Piston for internal combustion engine |
| US20100101527A1 (en) * | 2007-04-21 | 2010-04-29 | Ks Kolbenschmidt Gmbh | Load-optimized interior of a piston |
| CN201679576U (en) * | 2010-03-30 | 2010-12-22 | 山东滨州渤海活塞股份有限公司 | Integral aluminium-alloy piston bearing explosion pressure of 20MPa and having inner-cooling structure |
| CN217270508U (en) * | 2022-02-16 | 2022-08-23 | 山东双港活塞股份有限公司 | Lightweight piston |
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| Publication number | Publication date |
|---|---|
| CN116971887B (en) | 2024-02-23 |
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