WO2021248603A1

WO2021248603A1 - Connecting rod assembly

Info

Publication number: WO2021248603A1
Application number: PCT/CN2020/101027
Authority: WO
Inventors: 邓发平; 潘永亮; 何道明; 姚克甫; 赵明祥; 马百坦; 石黄涛; 刘代玉
Original assignee: 东风柳州汽车有限公司
Priority date: 2020-06-10
Filing date: 2020-07-09
Publication date: 2021-12-16
Also published as: CN111664162A

Abstract

A connecting rod assembly, comprising pistons (1), connecting rod bodies (2) rotatably mounted on the pistons (1), and a crankshaft (3); the pistons (1) are each provided with a piston pin (4), one end of a connecting rod body (2) is provided with a pin hole (8) and is rotatably sleeved on the piston pin (4), the other end of the connecting rod body (2) is connected to a connecting rod cover (5), the connecting rod cover (5) and the connecting rod body (2) together form a shaft hole (9), the connecting rod bodies (2) are each further provided with an oil passage (21), the shaft hole (9) communicates with the pin hole (8) by means of the oil passage (21), main journals (31) of the crankshaft (3) and connecting rod journals (32) of the crankshaft (3) are respectively provided with shaft oil intake holes (33) and shaft oil outlet holes (34) that communicate with one another, and the oil passages (21) of the connecting rod bodies (2) communicate with the shaft oil outlet holes (34) of the crankshaft (3), the shaft holes (9) are each internally provided with a bearing bush (61, 62), the crankshaft (3) is mounted inside of the bearing bushes (61, 62), the inner walls of the shaft holes (9) are provided with oil grooves (7) that communicate with the oil passages (21), the bearing bushes (61, 62) are each provided with a bush hole (63), and the shaft oil outlet holes (34) on the crankshaft (3) communicate with the oil grooves (7) by means of the bush holes (63). The connecting rod assembly forcibly lubricates the pin holes (8) and the piston pins (4) of the connecting rod bodies (2), thus preventing wear of the pin holes (8) and the piston pins (4), improving the service life of the whole machine, and increasing the NVH level of the whole machine.

Description

A connecting rod assembly

Technical field

The invention relates to the technical field of engines, in particular to a connecting rod assembly.

Background technique

Both gasoline and diesel engines are common engines, both of which are reciprocating piston internal combustion engines, and the piston-connecting rod mechanism is the main movement mechanism. In the existing engine technology, the engine oil cannot effectively lubricate the piston pin. Generally, after the engine temperature rises, the oil gas after the engine oil and gasification is used to passively lubricate the piston pin and the small end of the connecting rod. The passive oil and gas lubrication scheme is adopted, although the cost Low, but the engine does not reach the oil-gas temperature during this period, because there is no oil-gas generation, the lubrication effect is poor. Even if oil and gas are generated, the oil and gas are randomly distributed in the engine, and the amount of oil and gas reaching the small end of the connecting rod is not enough to produce liquid lubrication, so the lubrication cannot achieve the expected effect. There is also a way to perform forced lubrication by adding nozzles, which is an active lubrication method. However, the addition of a nozzle to each cylinder leads to a significant increase in cost and poor economy. At the same time, the cylinder body also increases machining and cylinders. The layout of the body oil passage is complicated, and the cost of the cylinder body is also increased.

Summary of the invention

In view of the technical problems existing in the prior art, the purpose of the present invention is to provide a connecting rod assembly. The present invention can forcibly lubricate the pin hole and piston pin of the connecting rod body to avoid the pin hole and the piston pin. Abrasion and the occurrence of problems such as noise, vibration and harshness.

In order to achieve the above objective, the present invention adopts the following technical solutions:

A connecting rod assembly includes a piston, a connecting rod body rotatably mounted on the piston, and a crankshaft; the piston is provided with a piston pin, one end of the connecting rod body is provided with a pin hole and is rotatably sleeved on the piston pin, and the connecting rod The other end of the body is connected with a connecting rod cover. The connecting rod cover and the connecting rod body together form a shaft hole. The crankshaft is rotatably installed in the shaft hole. The connecting rod body is also provided with an oil passage. The shaft hole is connected to the pin hole through the oil passage. , The crankshaft is provided with a shaft oil inlet hole and a shaft oil outlet hole communicated with each other, and the oil passage of the connecting rod body is communicated with the shaft oil outlet hole of the crankshaft.

As a preferred solution, the crankshaft includes a plurality of main journals and a plurality of connecting rod necks, the main journals and the connecting rod journals are arranged alternately, the shaft oil inlet hole is located on the main journal, and the shaft oil outlet hole is located on the connecting rod neck. , The crankshaft is also provided with an oil passage connecting the shaft oil inlet hole and the shaft oil outlet hole, and the connecting rod neck is located in the shaft hole.

As a preferred solution, a bearing bush is provided in the shaft hole, the connecting rod journal of the crankshaft is installed in the bearing bush, the inner wall of the shaft hole is provided with an oil groove communicating with the oil passage, the bearing bush is provided with a bushing hole, and the shaft on the connecting rod neck is oiled The hole communicates with the oil groove through a tile hole.

As a preferred solution, there are at least two tile holes.

As a preferred solution, both the connecting rod body and the connecting rod cover are provided with half shaft holes, and the half shaft holes of the connecting rod body and the half shaft holes of the connecting rod cover jointly form a shaft hole;

The bearing shell includes an upper bearing shell and a lower bearing shell; both the upper bearing shell and the lower bearing shell are semicircular, the upper bearing shell is located in the half shaft hole of the connecting rod body, and the lower bearing shell is located in the half shaft hole of the connecting rod cover.

As a preferred solution, the shoe hole is provided at the connection of the upper bearing shell and the lower bearing shell, the two ends of the upper bearing shell are respectively connected with the two ends of the lower bearing shell to form a shoe hole, and the oil groove is located on the hole wall of the semi-shaft hole of the connecting rod body.

As a preferred solution, the shoe hole is located on the upper bearing bush, the angle between the line connecting the center of the shoe hole and the shaft hole and the line connecting the two ends of the upper bearing shell is less than or equal to 45°, and the oil groove is located at the half shaft hole of the connecting rod body. On the wall of the hole.

As a preferred solution, the shoe hole is located on the lower bearing shell, the angle between the line connecting the center of the shoe hole and the shaft hole and the connecting line between the two ends of the lower bearing shell is less than or equal to 45°, and the oil groove is arranged along the inner circumferential wall of the shaft hole.

As a preferred solution, the piston is also provided with a rod mounting cavity, the piston pin is located in the rod mounting cavity, the hole wall of the pin hole is provided with a rod oil return hole, the pin hole communicates with the rod mounting cavity through the rod oil return hole, and the rod returns oil There is a chamfer on the hole.

As a preferred solution, the wall thickness of the oil passage is greater than or equal to 2 mm, and the diameter of the oil passage is greater than or equal to 1 mm and less than or equal to 2.5 mm.

In general, compared with the prior art, the present invention has the beneficial effects that: the present invention has a clever structure and does not need to add an oil nozzle to actively lubricate the piston and connecting rod body, which not only greatly reduces the cost, but also avoids Complicated machining and layout of cylinder oil passages. This application uses the high-pressure oil in the cylinder to flow from the shaft oil inlet hole of the main journal through the connecting rod neck, the shaft hole of the connecting rod body, the oil passage of the connecting rod body, and the pin hole, and finally flow to the piston pin for active Lubrication, this kind of active lubrication has a better effect than passive lubrication; it has a lower cost than the active lubrication method of adding nozzles. The forced lubrication of the piston pin and the pin hole of the connecting rod body through this application can not only avoid the pin and hole wear, but also avoid the occurrence of NVH (noise, vibration and harshness, etc.) problems, and improve the engine’s performance Service life.

Description of the drawings

Figure 1 is a schematic diagram of the connecting rod assembly.

Figure 2 is a schematic diagram of the connecting rod body and the connecting rod cover.

Fig. 3 is an internal cut-away structure diagram of the connecting rod body and the connecting rod cover.

Fig. 4 is a schematic diagram of the structure of the shaft hole of the connecting rod body.

Fig. 5 is a side view of the connecting rod body and the connecting rod cover.

Fig. 6 is a cross-sectional view at A-A in Fig. 5.

Fig. 7 is a schematic diagram of the structure of the crankshaft.

Figure 8 is a schematic diagram of the regional distribution of the tile holes on the bearing bush.

In the figure, 1 is the piston, 2 is the connecting rod body, 3 is the crankshaft, 4 is the piston pin, 5 is the connecting rod cover, 6 is the bearing bush, 7 is the oil groove, 8 is the pin hole, 9 is the shaft hole, 11 is the rod installation In the cavity, 21 is the oil passage, 22 is the rod oil return hole, 23 is the chamfer, 31 is the main journal, 32 is the connecting rod neck, 33 is the shaft oil inlet, 34 is the shaft oil outlet, and 35 is the oil passage, 61 is the upper bearing, 62 is the lower bearing, and 63 is the tile hole.

detailed description

The specific implementation of the present invention will be described in further detail below in conjunction with the accompanying drawings and embodiments. The following examples are used to illustrate the present invention, but not to limit the scope of the present invention.

As shown in Figures 1 to 7, this embodiment provides a connecting rod assembly, including a piston 1, a connecting rod body 2 rotatably mounted on the piston 1, a crankshaft 3; a piston pin 4 is fixed on the piston 1, and a connecting rod One end of the body 2 is provided with a pin hole 8, the connecting rod body 2 is rotatably sleeved on the piston pin 4 through the pin hole 8, the connecting rod and the piston pin are in clearance fit and can rotate, and the connecting rod body 2 rotates around the piston pin 4. A connecting rod cover 5 is connected to the other end of the connecting rod body 2, and the connecting rod cover 5 is fixedly connected to the connecting rod body 2 by bolts. The connecting rod cover 5 and the connecting rod body 2 jointly form a shaft hole 9, and the crankshaft 3 is rotatably mounted in the shaft hole 9 so that the connecting rod body 2 is rotatably sleeved on the crankshaft 3 through the shaft hole 9. The connecting rod body 2 is also provided with an oil passage 21, which is located on the center line of the connecting rod body 2. The oil passage is a through hole extending along the center line (length direction) of the connecting rod, and the shaft hole 9 passes through the oil passage 21 is in communication with the pin hole 8, and the oil flows from the shaft hole 9 to the pin hole 8 through the oil passage 21, so as to realize the lubrication of the piston pin 4 and avoid the wear between the piston pin 4 and the connecting rod body 2. The shaft hole 9 is a large end hole (big end hole) of the connecting rod, and the pin hole 8 is a small end hole (small end hole) of the connecting rod.

The circumferential side of the crankshaft 3 is provided with a shaft oil inlet 33 and a shaft oil outlet 34 that communicate with each other. The oil passage 21 of the connecting rod body 2 communicates with the shaft oil outlet 34 of the crankshaft 3, and the crankshaft 3 is rotatably installed in the oil cylinder. Under the action of high pressure, the high-pressure oil in the oil cylinder flows from the shaft oil inlet 33 to the shaft oil outlet 34 and then enters the oil passage 21, and finally reaches the pin hole 8 and the piston pin 4 to achieve forced lubrication.

The crankshaft 3 includes a plurality of main journals 31 and a plurality of connecting rod journals 32. The main journals 31 and the connecting rod journals 32 are arranged on different axes and staggered. The rotation axes of the main journals 31 and the connecting rod journals 32 are not on the same straight line. The hosel 32 is alternately arranged, a connecting rod neck 32 is arranged between the two main shaft necks 31, and a main shaft neck 31 is arranged between the two connecting rod necks 32. The shaft oil inlet hole 33 is located on the main shaft journal 31, and the shaft oil outlet hole 34 is located on the connecting rod journal 32. The crankshaft 3 is also provided with an oil passage 35 connecting the shaft oil inlet 33 and the shaft oil outlet 34. The oil passage 35 is located inside the crankshaft 3, as shown in the direction of the arrow in FIG. The oil inlet 33 enters, and then passes through the engine oil passage 35 to the shaft oil outlet 34 of the connecting rod neck 32. The connecting rod neck 32 is rotatably sleeved in the shaft hole 9, and the oil in the oil passage 35 flows from the shaft oil outlet hole 34 to the shaft hole 9 of the connecting rod body 2.

A bearing bush 6 is arranged in the shaft hole 9, the bearing bush 6 is annular, the bearing bush 6 is sleeved on the connecting rod neck 32 of the crankshaft 3, and the connecting rod body 2 and the connecting rod cover 5 are jointly sleeved on the outside of the bearing bush 6. The connecting rod neck 32 of the crankshaft 3 is installed in the bearing bush 6, the inner wall of the shaft hole 9 is provided with an oil groove 7 communicating with the oil passage 21, the bearing bush 6 is provided with a shoe hole 63, and the shaft oil outlet hole 34 on the connecting rod neck 32 The oil is connected to the oil groove 7 through the shoe hole 63, and the oil flows out from the shaft oil outlet hole 34 of the connecting rod neck 32, then flows from the shoe hole 63 to the oil groove 7, and finally flows from the oil groove 7 to the oil passage 21.

There are at least two tile holes 63. When there are two tile holes, the two tile holes are symmetrically distributed on the bearing bush 6 with the center line of the connecting rod body 2. The diameter of the tile hole 63 is 0.5-3mm, preferably 1mm.

Both the connecting rod body 2 and the connecting rod cover 5 are provided with half-shaft holes. The half-shaft holes are semicircular. The half-shaft holes are equivalent to half-shaft holes (half round holes). The half-shaft holes on the connecting rod body 2 and The half-shaft holes on the connecting rod cover 5 jointly form a shaft hole 9. The bearing 6 includes an upper bearing 61 and a lower bearing 62; the upper bearing 61 and the lower bearing 62 are both semicircular (semi-circular), and the upper bearing 61 and the lower bearing 62 together form an annular bearing 6. The upper bearing shell 61 is located in the half shaft hole of the connecting rod body 2, and the lower bearing shell 62 is located in the half shaft hole of the connecting rod cover 5.

The first setting method of the tile hole 63 is: the tile hole 63 is set at the joint of the upper bearing 61 and the lower bearing 62, and both ends of the upper bearing 61 and the lower bearing 62 are provided with half a tile hole, that is, the upper Both ends of the bearing bush 61 have half a tile hole (half a round hole), and both ends of the lower bearing bush 62 have a half tile hole. The two ends of the upper bearing shell 61 are respectively connected with the two ends of the lower bearing shell 62 to form a tile hole 63. The half hole at one end of the upper bearing shell 61 and the half hole at one end of the lower bearing shell 62 together form a tile hole 63. The upper bearing bush 61 The half tile hole at the other end and the half tile hole at the other end of the lower bearing 62 together form another tile hole 63, and the tile hole 63 is located at the junction of the connecting rod body 2 and the connecting rod cover 5. The oil groove 7 has a semicircular shape (semi-circular ring shape) and is located on the inner wall of the semi-shaft hole on the connecting rod body 2.

The second setting method of the tile hole 63 is: the tile hole 63 is located on the upper bearing 61, and the angle between the line connecting the center of the tile hole 63 and the shaft hole 9 and the connecting line between the two ends of the upper bearing 61 is less than or equal to 45 °, that is, the tile hole 63 is located in the areas A1 and A2 in FIG.

The third setting method of the tile hole 63 is: the tile hole 63 is located on the lower bearing shell 62, and the angle between the line connecting the center of the tile hole 63 and the shaft hole 9 and the connecting line between the two ends of the lower bearing shell 62 is less than or equal to 45 °, that is, the tile hole 63 is located in the area B1 and B2 in FIG. .

The bearing bush rotates during normal operation. When the bearing bush is turned to a certain position, the bush hole is connected with the shaft oil outlet hole of the connecting rod neck. At this time, the oil can flow from the shaft oil hole to the bush hole and then to the oil groove. When the engine is ignited and burned, an explosion will occur inside, and the explosion pressure will be transmitted along the piston 1, the piston pin 4, and the connecting rod body 2. When the pressure is transmitted to the bearing bush 6, it is generally not affected by the stress within the area of the above-mentioned three tile hole 63 setting methods, so it is necessary to set the tile hole in the area of the above three tile hole 63 setting methods 63. Because of the influence of stress in other areas, tile holes 63 are not opened. To sum up, in order to increase the service life of the bearing bush 6, the bush holes are arranged in the area where A1, A2, B1, and B2 are located on the bearing bush. The range of α in Fig. 8 is: 0°≤α≤45°.

The piston 1 is also provided with a rod mounting cavity 11, the piston pin 4 is located in the rod mounting cavity 11, and both ends of the piston pin 4 are fixed on the inner wall of the rod mounting cavity 11 of the piston 1. The inner wall of the pin hole 8 is provided with a rod oil return hole 22. There are two rod oil return holes 22 and are symmetrically distributed about the center line of the connecting rod body 2. The pin hole 8 communicates with the rod mounting cavity 11 through the rod oil return hole 22. After the piston pin 4 is forcibly lubricated, the oil flows from the rod oil return hole 22 to the rod mounting cavity 11, and finally returns to the oil cylinder to realize the circulating flow of oil, so that Lubrication is more efficient and stable. The rod oil return hole 22 is provided with a chamfer 23, the chamfer 23 is located on the outer surface of the connecting rod body 2, and the chamfer 23 is convenient to remove the burrs generated when the rod oil return hole 22 is machined.

The wall thickness of the oil passage 21 is greater than or equal to 2 mm, and the wall thickness is D in FIG. 6. If the wall thickness is too small or the cross-sectional area of the connecting rod body 2 is too small, it will cause excessive stress on the connecting rod body 2. Increased vibration. The diameter of the oil passage 21 is greater than or equal to 1 mm and less than or equal to 2.5 mm. If the hole diameter is too large, the strength of the connecting rod body 2 will be affected, and if the hole diameter is too small, machining will be difficult. For example, holes with a diameter of less than 1mm are easily broken when processed with a drill.

The working process of the present invention is as follows: when the engine is started, the piston drives the connecting rod body to reciprocate, the oil in the cylinder enters the oil passage from the shaft oil inlet of the crankshaft, and then flows out from the shaft oil outlet, and then the oil flows from the bearing bush. The hole flows to the oil groove, and then flows from the oil groove to the pin hole through the oil passage to realize the forced lubrication of the piston pin. After the piston pin is lubricated, the oil flows from the rod oil return hole to the rod mounting cavity, and finally returns to the cylinder. Repeat the above process to realize the forced continuous lubrication of the piston pin.

The above are only the preferred embodiments of the present invention. It should be pointed out that for those of ordinary skill in the art, without departing from the technical principles of the present invention, several improvements and substitutions can be made. These improvements and substitutions It should also be regarded as the protection scope of the present invention.

Claims

A connecting rod assembly includes a piston, a connecting rod body rotatably mounted on the piston, and a crankshaft; the piston is provided with a piston pin, one end of the connecting rod body is provided with a pin hole and is rotatably sleeved On the piston pin, a connecting rod cover is connected to the other end of the connecting rod body, the connecting rod cover and the connecting rod body jointly form a shaft hole, the crankshaft is rotatably mounted in the shaft hole, and It is characterized in that: the connecting rod body is further provided with an oil passage, the shaft hole is communicated with the pin hole through the oil passage, and the crankshaft is provided with a shaft oil inlet hole and a shaft oil outlet hole that communicate with each other, The oil passage of the connecting rod body communicates with the shaft oil outlet of the crankshaft.
The connecting rod assembly according to claim 1, wherein the crankshaft includes a plurality of main journals and a plurality of connecting rod journals, the main journals and the connecting rod journals are staggered, and the shaft oil inlet hole is located in the main shaft On the neck, the shaft oil outlet hole is located on the connecting rod neck, the crankshaft is also provided with an oil passage connecting the shaft oil inlet hole and the shaft oil outlet hole, and the connecting rod body passes through the shaft The hole is assembled on the connecting rod neck of the crankshaft.
The connecting rod assembly according to claim 2, wherein a bearing bush is provided in the shaft hole, the connecting rod journal of the crankshaft is located in the bearing shell, and the inner wall of the shaft hole is provided with An oil groove communicating with the oil passage, the bearing bush is provided with a shoe hole, and the shaft oil outlet hole on the connecting rod neck is communicated with the oil groove through the shoe hole.
The connecting rod assembly according to claim 3, wherein there are at least two tile holes.
A connecting rod assembly according to claim 3, wherein the connecting rod body and the connecting rod cover are both provided with half shaft holes, and the half shaft holes of the connecting rod body and the connecting rod The half shaft holes of the rod cover jointly form the shaft hole;

The bearing shell includes an upper bearing shell and a lower bearing shell; the upper bearing shell and the lower bearing shell are both semicircular, the upper bearing shell is located in the semi-shaft hole of the connecting rod body, and the lower bearing shell is located in the connecting rod cover In the half-shaft hole.
The connecting rod assembly according to claim 5, wherein the shoe hole is provided at the connection of the upper bearing shell and the lower bearing shell, and the oil groove is located in the semi-shaft hole of the connecting rod body On the wall of the hole.
The connecting rod assembly according to claim 5, characterized in that: the shoe hole is located on the upper bearing bush, and the line connecting the center of the shoe hole and the shaft hole is connected to two of the upper bearing bush The angle between the connecting lines of the ends is less than or equal to 45°, and the oil groove is located on the inner wall of the semi-axial hole of the connecting rod body.
The connecting rod assembly according to claim 5, characterized in that: the shoe hole is located on the lower bearing bush, and the line connecting the center of the shoe hole and the shaft hole is connected to the two connecting rods of the lower bearing bush. The angle between the connecting lines of the ends is less than or equal to 45°, and the oil groove is arranged along the circumferential inner wall of the shaft hole.
The connecting rod assembly according to claim 1, wherein the piston is further provided with a rod mounting cavity, the piston pin is located in the rod mounting cavity, and the hole wall of the pin hole is provided There is a rod oil return hole, the pin hole communicates with the rod installation cavity through the rod oil return hole, and the rod oil return hole is provided with a chamfer.
The connecting rod assembly according to claim 1, wherein the wall thickness of the oil passage is greater than or equal to 2 mm, and the diameter of the oil passage is greater than or equal to 1 mm and less than or equal to 2.5 mm.