A lubricating structure of an engine camshaft

Abstract

The utility model discloses a kind of lubricating structures of engine camshaft, belong to camshaft lubrication technical field, solve the problem of splash lubrication to the limited lubrication of camshaft, affect service life. The lubricating structure of the engine camshaft, including camshaft body, one end of the camshaft body is equipped with head journal, the other end of the camshaft body is equipped with tail journal, multiple lubricating journals are equipped between the head journal and tail journal, the camshaft body is also equipped with multiple inlet cam, exhaust cam, and multiple the inlet cam, exhaust cam of described are arranged at intervals, the camshaft body is equipped with lubricating oil cavity, and one end of the lubricating oil cavity extends to the end face of one end of camshaft body, plug is inserted in one end of the lubricating oil cavity, the lubricating journal is equipped with oil inlet hole that the main oil passage of engine is communicated with lubricating oil cavity. The lubricating structure of the engine camshaft of the utility model effectively prolongs its service life.

Description

Technical Field

[0001] This utility model relates to the field of camshaft lubrication technology, and more specifically, to a lubrication structure for an engine camshaft. Background Technology

[0002] The camshaft is mainly used to control the opening and closing timing and lift of the engine valves, directly affecting intake and exhaust efficiency. After long-term operation, the camshaft profile may wear down, leading to a decrease in valve lift (e.g., the measured data falls below the lower limit), which in turn affects the accuracy of valve action, and consequently, the engine's combustion efficiency and power output.

[0003] Currently, engines primarily rely on splash lubrication to cool and lubricate the camshaft. However, splash lubrication has the following drawbacks: 1. Lubrication is uncontrollable and imprecise; the lubrication effect depends entirely on the oil droplets or mist "splashed" up by moving parts. The landing point and amount of oil droplets cannot be precisely controlled, potentially leading to insufficient and unstable oil supply to critical parts requiring heavy lubrication (such as the cam lobe); 2. Cooling effect is poor. Pressure circulation lubrication systems can force oil to the hot load areas requiring cooling via an oil pump, thus carrying away heat. Splash lubrication cannot achieve this directional, forced cooling; the lubrication effect of sporadic splashed oil droplets is very limited, and long-term use can damage the camshaft, affecting its service life. Utility Model Content

[0004] The technical problem to be solved by this utility model is to address the above-mentioned shortcomings of the prior art by providing a lubrication structure for an engine camshaft that provides sufficient oil lubrication for the camshaft and effectively extends its service life.

[0005] The technical solution of this utility model is as follows: a lubrication structure for an engine camshaft, including a camshaft body, a head journal at one end of the camshaft body, a tail journal at the other end of the camshaft body, a plurality of lubrication journals between the head journal and the tail journal, a plurality of intake cams and exhaust cams on the camshaft body, the plurality of intake cams and exhaust cams being arranged at intervals, a lubrication oil chamber inside the camshaft body, one end of the lubrication oil chamber extending to the end face of one end of the camshaft body, a plug being inserted into one end of the lubrication oil chamber, an oil inlet hole on the lubrication journal connecting the engine main oil passage to the lubrication oil chamber, and an oil outlet hole on the intake cam and exhaust cam communicating with the lubrication oil chamber.

[0006] As a further improvement, the other end of the lubricating oil cavity extends to one end of the camshaft body near the head journal.

[0007] Furthermore, the ratio of the length of the lubricating oil cavity to the length of the camshaft body is 0.8, and the ratio of the diameter of the lubricating oil cavity to the diameter of the camshaft body is 0.6.

[0008] Furthermore, the lubricating oil cavity is provided with a conical structure with a gradually decreasing diameter at one end near the head journal.

[0009] Furthermore, both the intake cam and the exhaust cam include a base circle and a cam tip, the bottom of which is tangent to the base circle, and the oil outlet is located at the junction of the base circle and the cam tip.

[0010] Furthermore, the oil outlet is located at the middle position in the width direction of the intake cam or exhaust cam.

[0011] Furthermore, the ratio of the sum of the cross-sectional areas of the plurality of oil inlets to the sum of the cross-sectional areas of the plurality of oil outlets is 1.5:1.

[0012] Furthermore, the length-to-diameter ratio of the oil outlet is 1:5.

[0013] Furthermore, the plug is made of 304 stainless steel.

[0014] Furthermore, at least one sealing groove is provided on the outer wall surface of the blockage, and a sealing ring is engaged in the sealing groove.

[0015] Beneficial effects Compared with the prior art, this utility model has the following advantages: This utility model discloses a lubrication structure for an engine camshaft. The oil inlet on the camshaft body is connected to the main oil passage on the camshaft mounting hole of the engine block. The oil in the oil passage enters the lubrication chamber 7 through the oil inlet and fills the lubrication chamber. Then, the oil flows into each corresponding intake cam or exhaust cam through the oil outlet on the camshaft body. This lubrication structure can accurately lubricate and cool each intake cam or exhaust cam, thereby protecting the camshaft body from wear and effectively extending its service life. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the main structure of this utility model; Figure 2 This is a cross-sectional structural diagram of the present invention; Figure 3 This is a schematic diagram of the left-side cross-sectional structure of the intake cam or exhaust cam of this utility model; Figure 4 This is a cross-sectional structural diagram of the blockage in this utility model.

[0017] Among them: 1-camshaft body, 2-head journal, 3-tail journal, 4-lubricating journal, 5-intake cam, 6-exhaust cam, 7-lubricating oil chamber, 8-oil inlet hole, 9-oil outlet hole, 10-plug, 11-base circle, 12-cam tip, 13-sealing ring, 14-sealing groove, 15-conical structure. Detailed Implementation

[0018] The present invention will be further described below with reference to specific embodiments shown in the accompanying drawings.

[0019] See Figure 1-4 A lubrication structure for an engine camshaft includes a camshaft body 1, a head journal 2 at one end of the camshaft body 1, a tail journal 3 at the other end of the camshaft body 1, a plurality of lubrication journals 4 between the head journal 2 and the tail journal 3, a plurality of intake cams 5 and exhaust cams 6 on the camshaft body 1, the plurality of intake cams 5 and exhaust cams 6 being arranged at intervals, a lubrication oil chamber 7 inside the camshaft body 1, one end of the lubrication oil chamber 7 extending to the end face of one end of the camshaft body 1, a plug 10 inserted into one end of the lubrication oil chamber 7, an oil inlet hole 8 on the lubrication journal 4 connecting the engine main oil passage to the lubrication oil chamber 7, and an oil outlet hole 9 on the intake cams 5 and exhaust cams 6 communicating with the lubrication oil chamber 7.

[0020] When the engine is running, the engine oil is pumped from the oil pan through the oil passages to various parts of the engine. At this time, because the oil inlet 8 on the camshaft body 1 is connected to the main oil passage on the camshaft mounting hole of the engine block, the oil in the oil passage will enter the lubrication chamber 7 through the oil inlet 8 and fill the lubrication chamber 7. Then the oil will flow through the oil outlet 9 on the camshaft body 1 into each corresponding intake cam 5 or exhaust cam 6. This lubrication structure can accurately lubricate and cool each intake cam 5 or exhaust cam 6, thereby protecting the camshaft body 1 from wear and effectively extending its service life.

[0021] In this embodiment, the other end of the lubricating oil cavity 7 extends to one end of the camshaft body 1 near the head journal 2, and one end of the lubricating oil cavity 7 extends to the end face of one end of the camshaft body 1. A plug 10 is installed at one end of the lubricating oil cavity 7. Therefore, no oil inlet hole 8 is provided on the head journal 2 and the tail journal 3 on the camshaft body 1. At the same time, the other end of the lubricating oil cavity 7 extends to one side of the head journal 2, which effectively ensures the overall structural strength of the camshaft body 1.

[0022] In this embodiment, the ratio of the length of the lubricating oil cavity 7 to the length of the camshaft body 1 is 0.8, and the ratio of the diameter of the lubricating oil cavity 7 to the diameter of the camshaft body 1 is 0.6. The length and diameter of the lubricating oil cavity 7 determine its volume. If the volume is too small, its pressure storage and stabilization capacity will be poor, and the oil pressure will be unstable, affecting the lubrication effect. This ratio ensures that the oil pressure stability in the lubricating oil cavity 7 is the best without affecting the overall structural strength of the camshaft body 1, thus effectively improving the lubrication effect.

[0023] In this embodiment, the lubricating oil cavity 7 is provided with a tapered structure 15 with a gradually decreasing diameter at one end near the head journal 2. This can prevent stress concentration points from forming at the end of the lubricating oil cavity 7 near the head journal 2, which may cause cracks and shaft breakage under high loads, and effectively extend the service life of the camshaft body 1.

[0024] In this embodiment, both the intake cam 5 and the exhaust cam 6 include a base circle 11 and a cam tip 12. The bottom of the cam tip 12 is tangent to the base circle 11, and the oil outlet 9 is located at the junction of the base circle 11 and the cam tip 12. During the movement of the camshaft body 1, the cam tip 12 in the intake cam 5 or the exhaust cam 6 experiences the greatest wear. Setting the oil outlet 9 at the junction of the base circle 11 and the cam tip 12 can better lubricate the cam tip 12 and effectively improve the lubrication effect.

[0025] In this embodiment, the oil outlet 9 is located at the middle position in the width direction of the intake cam 5 or the exhaust cam 6. The oil flowing out of the oil outlet 9 located at the middle position in the width direction of the intake cam 5 or the exhaust cam 6 can better lubricate both sides of the intake cam 5 or the exhaust cam 6, effectively improving the lubrication effect.

[0026] In this embodiment, the ratio of the sum of the cross-sectional areas of the multiple oil inlet holes 8 to the sum of the cross-sectional areas of the multiple oil outlet holes 9 is 1.5:1. The sum of the cross-sectional areas of the multiple oil inlet holes 8 is greater than the sum of the cross-sectional areas of the multiple oil outlet holes 9, so as to ensure that the oil can fully fill the oil cavity and maintain sufficient oil pressure, so that the oil can flow out evenly from each oil outlet hole 9, effectively improving the lubrication effect.

[0027] In this embodiment, the length-to-diameter ratio of the oil outlet hole 9 is 1:5. The smaller the length-to-diameter ratio of the oil outlet hole 9, the less resistance the oil in the lubrication chamber 7 will have to flow through the oil outlet hole 9, which effectively improves the lubrication effect on the intake cam 5 and the exhaust cam 6.

[0028] In this embodiment, the plug 10 is made of 304 stainless steel, which has excellent corrosion resistance and heat resistance, a longer service life, and effectively improves the sealing effect of the plug 10.

[0029] In this embodiment, at least one sealing groove 14 is provided on the outer wall surface of the plug 10. There are two sealing grooves 14 in total. In other embodiments, the number of sealing grooves 14 can be increased according to the actual situation to further enhance the sealing between the plug 10 and the lubricating oil cavity 7. A sealing ring 13 is snapped into the sealing groove 14 to effectively enhance the sealing between the plug 10 and the lubricating oil cavity 7.

[0030] The above description is only a preferred embodiment of the present utility model. It should be noted that for those skilled in the art, several modifications and improvements can be made without departing from the structure of the present utility model. These modifications and improvements will not affect the effectiveness of the present utility model or the practicality of the patent.

Claims

1. A lubrication structure for an engine camshaft, comprising a camshaft body (1), one end of which is provided with a head journal (2), and the other end of which is provided with a tail journal (3), wherein a plurality of lubrication journals (4) are provided between the head journal (2) and the tail journal (3), and the camshaft body (1) is further provided with a plurality of intake cams (5) and exhaust cams (6), wherein the plurality of intake cams (5) and exhaust cams (6) are arranged at intervals, characterized in that, The camshaft body (1) is provided with a lubricating oil chamber (7), and one end of the lubricating oil chamber (7) extends to the end face of the camshaft body (1) near the tail journal (3). A plug (10) is inserted into one end of the lubricating oil chamber (7). The lubricating journal (4) is provided with an oil inlet hole (8) that connects the main oil passage of the engine to the lubricating oil chamber (7). The intake cam (5) and exhaust cam (6) are both provided with an oil outlet hole (9) that connects to the lubricating oil chamber (7).

2. The lubrication structure for an engine camshaft according to claim 1, characterized in that, The other end of the lubricating oil cavity (7) extends to one end of the camshaft body (1) near the head journal (2).

3. The lubrication structure for an engine camshaft according to claim 1, characterized in that, The length of the lubricating oil cavity (7) is 0.8 times the length of the camshaft body (1), and the diameter of the lubricating oil cavity (7) is 0.6 times the diameter of the camshaft body (1).

4. The lubrication structure for an engine camshaft according to claim 1, characterized in that, The lubricating oil cavity (7) has a conical structure (15) with a gradually decreasing diameter at one end near the head journal (2).

5. The lubrication structure for an engine camshaft according to claim 1, characterized in that, The intake cam (5) and exhaust cam (6) both include a base circle (11) and a cam tip (12). The bottom of the cam tip (12) is tangent to the base circle (11), and the oil outlet (9) is located at the junction of the base circle (11) and the cam tip (12).

6. The lubrication structure for an engine camshaft according to claim 5, characterized in that, The oil outlet (9) is located at the middle position in the width direction of the intake cam (5) or exhaust cam (6).

7. The lubrication structure for an engine camshaft according to claim 1, characterized in that, The ratio of the sum of the cross-sectional areas of the plurality of oil inlets (8) to the sum of the cross-sectional areas of the plurality of oil outlets (9) is 1.5:

1.

8. The lubrication structure for an engine camshaft according to claim 1, characterized in that, The length-to-diameter ratio of the oil outlet (9) is 1:

5.

9. The lubrication structure for an engine camshaft according to claim 1, characterized in that, The plug (10) is made of 304 stainless steel.

10. The lubrication structure for an engine camshaft according to claim 1, characterized in that, At least one sealing groove (14) is provided on the outer wall surface of the plug (10), and a sealing ring (13) is snapped into the sealing groove (14).

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