KR102672090B1 - Oil Pathway Differential Pressure Type Cam Shaft Lubrication System In Engine - Google Patents

Abstract

The engine 100 of the present invention has a roller wheel that communicates with the shaft flow path 20-2 of the camshaft 10 that opens and closes the intake/exhaust valve and communicates with the roller main flow path 21b through which oil rising from the engine block flows. A groove (23a) is formed in the roller wheel (30), and the inner wheel hole (23b), which sends the oil from the roller wheel groove (23a) toward the needle bearing (50), is an inner wheel (23b) surrounded by the needle bearing (50). 40), and includes a camshaft lubrication system (1) in which the roller main flow path (21b)/inner wheel hole (23b) is arranged in a staggered manner at an angle (K), thereby forming a roller wheel groove (23a)/ The oil flow path of the inner wheel hole (23b) allows adjustment of the amount of lubricating oil supplied without changing the oil hole size, and in particular, the amount of oil supplied can be additionally adjusted to suit the needs of the engine 100 while maintaining the minimum oil hole machining size. It has the characteristic of improving the friction reduction effect through constant oil contact at the mechanism contact area where the CVVD mechanism part (200-1) of the CVVD system (Continuously Variable Valve Duration System) 200 is connected while being shrinkable.

Description

Oil Pathway Differential Pressure Type Cam Shaft Lubrication System In Engine}

The present invention relates to the oil lubrication structure of an engine, and in particular to an engine equipped with a differential pressure-type camshaft lubrication system capable of controlling the oil flow rate at a constant oil hole size.

In general, vehicle engines are equipped with an oil lubrication structure to ensure that an appropriate amount of oil is sprayed into mechanical contact parts within the engine parts, thereby improving friction and wear on the contact mechanism.

An example of the oil lubrication structure is a camshaft lubrication system. The camshaft lubrication system collects oil from the engine block into the oil supply line inside the camshaft, forming a branched cam heel passage (i.e., the internal passage of the inner wheel and needle bearing joint) and the cam journal passage (i.e., the camshaft outer diameter and It is sent to the gap passage of the surrounding cam journal hub and then discharged out of the camshaft through the CVVD (Continuously Variable Valve Duration) passage.

Therefore, the camshaft lubrication system supplies oil to the inner wheel/needle bearing through the cam heel passage and to the camshaft outer diameter/cam journal hub through the cam journal passage, and supplies oil from the cam heel passage to the CVVD mechanism, which is the connection between the CVVD system and the camshaft. It improves friction and wear of the CVVD system by supplying it to the CVVD system.

Japanese Published Patent 2015-28329 (2015.02, 12)

However, the camshaft lubrication system requires optimization of the oil hole size by applying a branched structure of the oil hole.

For example, oil hole optimization adjusts the relative ratio of the oil hole size of the cam journal passage to the oil hole of the inner wheel passage (and/or the oil hole size of the CVVD passage) to prevent excessive oil injection through the oil hole on either side. You should be able to do it. This is because the amount of oil sprayed through the oil hole depends on the size of the oil hole processing, so when the oil supply to one part increases, the oil supply to other parts relatively decreases.

Therefore, for the camshaft lubrication system, it is important to select an appropriate oil hole machining size, but the minimum machining size of the oil hole is inevitably limited due to the influence of the type of processing tool and the working environment, which makes it difficult to select an appropriate oil hole machining size. It's being brought.

Accordingly, taking the above into consideration, the present invention enables control of the amount of lubricating oil supplied without changing the oil hole size by using an oil passage in which differential pressure is formed, and in particular, the amount of oil supplied while maintaining the minimum oil hole processing size. The purpose is to provide a flow differential pressure type camshaft lubrication system for the engine that can be further reduced to meet the needs of the engine system and improve the friction reduction effect through constant oil contact at the mechanism contact area.

The camshaft lubrication system of the present invention for achieving the above object is an inner wheel surrounding a roller wheel fixed to the camshaft, and an inner wheel passage for oil supply is formed, and the inner wheel passage is a roller wheel passage of the roller wheel. and a staggered arrangement according to the angle between the flow rate control passages of the inner wheel.

In a preferred embodiment, the included angle is an acute angle.

In a preferred embodiment, the roller wheel flow path is made of a roller wheel groove communicating with the roller main flow path drilled in the roller wheel, and the flow rate control flow path is made of an inner wheel hole drilled in the inner wheel to communicate with the roller wheel groove. The roller main flow path and the inner wheel hole form the included angle.

In a preferred embodiment, the roller wheel groove has a path passing through the outlet of the roller main flow passage. The path of the roller wheel groove is made at an obtuse angle and is dug to a depth where oil from the roller main flow path can stay. The depth forms one of a triangular cross-section, a semicircular cross-section, and a square cross-section.

In a preferred embodiment, the inner wheel hole discharges oil to the outer diameter of the inner wheel and the inner diameter of the needle bearing surrounding the inner wheel.

In a preferred embodiment, the roller wheel passage is drilled into the shaft body of the cam shaft and communicates with a shaft passage through which oil flows, thereby supplying oil. In the shaft passage, an inflow passage through which oil flows into the shaft passage, as well as a cam wheel passage through which oil is discharged from the shaft passage, and a cam journal passage through which oil flows into the shaft passage are communicated with each other at an interval. Each of the inflow passage, the cam wheel passage, and the cam journal passage is perforated in the radial direction of the cam shaft and is perpendicular to the shaft passage.

And to achieve the above object, the engine of the present invention includes a cam shaft having a cam that opens and closes the intake/exhaust valves; A roller wheel groove communicating with the shaft passage of the camshaft and the roller main passage through which oil from the engine block flows is formed on the roller wheel, and an inner wheel hole is formed to send oil from the roller wheel groove toward the needle bearing. A camshaft lubrication system formed on the inner wheel 40 surrounded by the needle bearing, wherein the roller main flow path and the inner wheel hole are arranged alternately at an angle; A CVVD system coupled to the camshaft to control the opening and closing of the intake/exhaust valves.

In a preferred embodiment, the included angle is formed to be 15 to 20°, and the roller wheel groove is dug in the roller wheel in an area of 120 to 150°.

In a preferred embodiment, the CVVD system is lubricated by the camshaft lubrication system, and the lubrication is achieved by supplying oil from the inner wheel hole.

The camshaft lubrication system applied to the engine of the present invention implements the following actions and effects by injecting oil in a differential pressure type flow path.

First, the amount of lubricating oil supplied to the inner wheel/needle bearing/cam journal of the camshaft and the CVVD system is adjusted without changing the oil hole size, thereby resolving the difficulty of selecting the optimal oil hole. Second, by applying a flow control groove instead of changing the oil hole size, the amount of oil supplied to the inner wheel side that requires a relatively small amount of lubrication can be minimized, and the amount of oil supplied to the cam journal side that requires a relatively large amount of lubrication can be increased. . Third, the flow rate supplied to the inner wheel of the camshaft can be changed depending on the groove processing shape for flow control. Fourth, the triangular cross-sectional shape of the flow control groove can reduce the flow rate supplied to the inner wheel side by about 65% compared to the existing conventional technology, while simultaneously increasing the amount of oil supplied to the cam journal side by about 61% compared to the existing conventional technology. Fifth, by keeping oil in the groove at all times, the frictional resistance generated by contact between the roller wheel and the inner wheel can be greatly improved with oil.

Figure 1 is a configuration diagram of a flow differential pressure type camshaft lubrication system according to the present invention, Figure 2 is a roller wheel configuration diagram of the camshaft lubrication system according to the present invention, and Figure 3 is an inner diagram of the camshaft lubrication system according to the present invention. It is a wheel configuration diagram, Figure 4 is an oil flow diagram in the cam wheel of the camshaft lubrication system according to the present invention, Figure 5 is an oil supply flow rate diagram according to the cross section of the roller wheel groove of the roller wheel according to the present invention, and Figure 6 is a diagram of the oil supply flow rate according to the cross section of the roller wheel groove of the roller wheel according to the present invention. This is an example of an engine to which the camshaft lubrication system according to the invention is applied.

Hereinafter, embodiments of the present invention will be described in detail with reference to the attached illustration drawings. These embodiments are examples and can be implemented in various different forms by those skilled in the art to which the present invention pertains, so they are described herein. It is not limited to the embodiment.

Referring to Figure 1, the camshaft lubrication system 1 includes a camshaft 10 and an oil lubrication line 20. In particular, the oil lubrication line 20 is provided with an inner wheel passage 20-5 in the cam heel 11, and the inner wheel passage 20-5 is a roller wheel 30 built into the cam heel 11. It is composed of a roller wheel passage 21 and a flow rate control passage 23 for the inner wheel 40 and needle bearing 50, so that it is possible to control the amount of lubricating oil supplied without changing the size of the oil hole due to the differential pressure in the passage. Therefore, the camshaft lubrication system (1) is called a flow differential pressure type camshaft lubrication system.

Specifically, the cam shaft 10 consists of a cam heel 11, a cam journal 13, a valve cam 15, and a shaft end 17.

For example, the cam heel 11 forms an inner wheel passage 20-5 for the built-in roller wheel 30, the inner wheel 40, and the needle bearing 50, and the CVVD system (Continuously Variable Valve Duration System) ) of the CVVD mechanism (see Figure 6) is combined. The cam journal 13 is a section between the cam heel 11 and the valve cam 15 (or a section between the valve cam 15 and the valve cam 15) and is a hub (e.g., a cam journal hub in FIG. 6). It is combined with (see 10-1)). The valve cams 15 are in contact with the valve tappets and are configured in a number consistent with the number of valves provided in the engine cylinder. The shaft end 17 is the end portion of the cam shaft 10 and is connected to a belt to transmit rotational force. Therefore, the camshaft 10 is a camshaft typically applied to an engine.

Specifically, the oil lubrication line 20 includes an inflow passage 20-1, a shaft passage 20-2, a cam wheel passage 20-3, a cam journal passage 20-4, and an inner wheel passage 20-4. 5) and is distinguished by the following structural characteristics.

For example, the inflow passage 20-1, the shaft passage 20-2, the cam wheel passage 20-3, and the cam journal passage 20-4 are conventional oil formed on the cam shaft 10. Construct a lubrication line.

Therefore, the inflow passage 20-1 is drilled in the radial direction of the shaft body of the camshaft 10, and acts as a passage through which oil rising from the engine block flows into the inside of the camshaft 10. The shaft passage 20-2 is drilled inside the axial body of the cam shaft 10 in the axial direction of the cam shaft 10, and communicates with the inflow passage 20-1 to provide an inflow passage 20-2. It is filled with oil supplied in 1). The cam wheel passage 20-3 is perforated in the radial direction of the cam heel 11, and the oil supplied from the shaft passage 20-2 is directed to an external mechanism (e.g., the CVVD mechanism 200 of FIG. 6). It communicates with the inner wheel flow path (20-5) to discharge to (see -1)). The cam journal passage 20-4 is drilled in the radial direction on the axial body of the cam shaft 10, and is connected to a hub (e.g., the cam journal hub 10- of FIG. 6) coupled to the cam journal 13. It communicates with the shaft passage 20-2 and receives oil so that the contact surface of (see 1)) is lubricated. Accordingly, each of the inflow passage 20-1, the cam wheel passage 20-3, and the cam journal passage 20-4 is perpendicular to the shaft passage 20-2.

On the other hand, the inner wheel passage 20-5 communicates with the shaft passage 20-2 through the roller wheel 30 coupled to the shaft body of the cam shaft 10 inside the cam heel 11, As the roller wheel 30 is combined with the inner wheel 40 surrounded by the needle bearing 50, the oil supplied from the shaft passage 20-2 is lubricated to the needle bearing 50 and then lubricated into the cam wheel passage 20-3. ) is discharged.

Specifically, the roller wheel 30, the inner wheel 40, and the needle bearing 50 are surrounded by the cam heel housing 11-1 and are built into the cam heel 11. Therefore, the assembly structure of the roller wheel 30, the inner wheel 40, and the needle bearing 50 is the same as before.

Meanwhile, referring to the cross section A-A of FIG. 1, the inner wheel passage 20-5 is divided into a roller wheel passage 21 formed in the roller wheel 30 and a flow rate control passage 23 formed in the inner wheel 40. .

For example, the roller wheel passage 21 consists of a roller shaft hole 21a, a roller main passage 21b, and a roller sub passage 21c formed in the roller wheel 30. The roller shaft hole 21a is drilled in the radial direction of the roller body 31 of the roller wheel 30, and the roller body 31 is inserted into the roller wheel hole 10A of the cam shaft 10. In this state, it communicates with the shaft flow path (20-2) and receives oil. The roller main flow path 21b and the roller sub flow path 21c are drilled in the roller body 31 and the roller head 33 of the roller wheel 30 in the axial direction, and the roller main flow path 21b ) is formed on the roller body 31 and the roller head 33 and communicates with the roller wheel groove 23a, while the roller sub passage 21c is formed on the roller body 31 and connects the roller wheel of the cam shaft 10. It communicates with the hall (10A). In particular, the roller main flow path (21b) has a larger diameter than the roller sub flow path (21c) and allows more oil to pass through than the roller sub flow path (21c).

For example, the flow rate control passage 23 consists of a roller wheel groove 23a and an inner wheel hole 23b. The roller wheel groove 23a is grooved along the surface of the roller head 33 of the roller wheel 30 and communicates with the roller main passage 21b, while the inner wheel hole 23b is formed by the roller wheel groove 23a. It is drilled into the inner wheel 40 to communicate with the length section of.

Therefore, the inner wheel passage 20-5 is the passage length of the roller wheel passage 21 and the flow rate control passage 23 through which oil flows from the roller wheel 30 to the needle bearing 50 through the inner wheel 40 ( That is, by forming a differential pressure in the flow path from the roller wheel groove (23a) and the length of the inner wheel hole (23b), the lubricating oil supply amount is adjusted without changing the oil hole size, and the oil storage function ensures constant oil contact with the needle bearing (50). possible.

Meanwhile, Figures 2 and 3 show detailed configurations of the roller wheel 30 and the inner wheel 40, respectively.

Referring to FIG. 2, the roller wheel 30 is composed of a cylindrical roller body 31 and a semi-cylindrical roller head 33 to form an approximately “T” shape, thereby forming the first roller wheel 30- 1) and the second roller wheel (30-2) are paired as a pair and an alternating angle (W) of about 90° is formed in the roller wheel pocket (43) of the inner wheel (40) (see FIG. 3). Therefore, the first roller wheel 30-1 and the second roller wheel 30-2 are formed by two roller wheels built into the cam heel 11 of the cam shaft 10. It is the same as a typical pair of roller wheels.

However, the roller wheel grooves 23a formed in each of the first roller wheel 30-1 and the second roller wheel 30-2 form the roller main flow path 21b on the semi-cylindrical surface of the roller head 33. It is dug to a predetermined depth to have an area of about 120 to 150° along the passing path, and the predetermined depth is formed at a depth at which oil from the roller main flow passage 21b can remain in the roller wheel groove 23a. Therefore, the oil paths formed in each of the first roller wheel 30-1 and the second roller wheel 30-2 are the roller shaft hole 21a, the roller main flow path 21b, and the roller sub flow path 21c. Unlike a typical oil path, there is a difference in that it consists of a roller shaft hole (21a), a roller main passage (21b), a roller sub passage (21c), and a roller wheel groove (23a).

In particular, the roller wheel groove 23a is processed into various cross-sectional shapes such as a triangular cross-section (A-shaped), a semicircular cross-section (B-shaped), and a square cross-section (C-shaped) through tool processing. In this case, the difference between the triangular cross section (A shape)/semicircular cross section (B shape)/square cross section (C shape) has a degree of difference, but improves the oil supply flow rate compared to the existing structure.

Referring to FIG. 3, the inner wheel 40 consists of an inner wheel body 41, a roller wheel pocket 43, and a sub channel 45.

For example, the inner wheel body 41 is cylindrical and forms a roller wheel pocket 43 and a sub channel 45, and a needle bearing 50 is surrounded inside the cam wheel 11. The roller wheel pocket 43 passes through the shaft body of the cam shaft 10 and positions the roller wheel 30 fixed to the shaft body. The sub-channel 45 is divided into a left sub-channel 45-1 and a right sub-channel 45-2, is located around the roller wheel pocket 43, and is filled with oil.

In particular, the roller wheel pocket 43 consists of a main pocket 43a with a large space, and a left head pocket 43a-1 and a right head pocket 43a-2 with a relatively small space. The main pocket 43a is where the roller body 31 of the roller wheel 30 is located along with the axis body of the cam shaft 10, and the left head pocket 43a-1 and the right head pocket 43a-2 are located in the main pocket 43a. In each, the roller head 33 of the roller wheel 30 is located.

Therefore, when the roller wheel 30 is divided into the first roller wheel 30-1 and the second roller wheel 30-2, the rollers of the first and second roller wheels 30-1 and 30-2 The body 31 is located in the main pocket 43a with first and second roller wheels 30-1, 30-2, and the roller head 33 of the first roller wheel 30-1 is located in the left head pocket ( 43a-1), while the roller head 33 of the second roller wheel 30-2 is positioned into the right head pocket 43a-2.

Therefore, the inner wheel hole 23b drilled in the inner wheel body 41 communicates with the roller wheel groove 23a located in the left head pocket 43a-1 (and/or the right head pocket 43a-2). In particular, the inner wheel hole 23b is arranged to have a crossing angle K of about 15 to 20° with respect to the roller main passage 21b. The larger the crossing angle, the larger the roller wheel. The length of the passage from the outlet of (30) (i.e., the roller main passage (21b)) to the entrance (i.e., the inner wheel hole (23b)) of the inner wheel 40 (i.e., the groove length of the roller wheel groove (23a) ) is longer, so the flow differential pressure effect also increases.

Referring to FIG. 4, when supplying oil 70 to the needle bearing 50, the inner wheel 40 adjusts the amount of lubricating oil supplied without changing the size of the oil hole due to differential pressure in the channel due to the long channel length and stores the oil. As a function, constant oil contact with the needle bearing 50 and the friction area is also possible. In this case, each of the first roller wheel 30-1 and the second roller wheel 30-2 constituting the roller wheel 30 implements the same lubrication action.

Meanwhile, Figure 5 illustrates a diagram of the oil supply flow rate compared to application of the roller wheel groove 23a compared to non-application.

Referring to the GAM journal oil supply flow rate diagram (A) in FIG. 5, when the supply pressure is 2.5 bar, the roller wheel groove (23a) with a triangular cross-section (A shape) increases the oil supply flow rate of the GAM journal (13) by about 61% compared to the existing one. %, the roller wheel groove (23a) with a semicircular cross-section (B shape) increases the oil supply flow rate to the gam journal (13) by about 39% compared to the existing one, and the roller wheel groove (23a) with a square cross-section (C shape) increases the oil supply flow rate to the gam journal (13) by about 39%. ) oil supply flow rate is increased by about 20% compared to the previous one.

In the inner heel oil supply flow rate diagram (B) of FIG. 5, when the supply pressure is 2.5 bar, the roller wheel groove (23a) of triangular cross-section (A shape) reduces the oil supply flow rate of the inner wheel (40) by about 65% compared to the previous one. In each case, the roller wheel groove 23a with a semicircular cross-section (B shape) and the roller wheel groove 23a with a square cross-section (C shape) have a smaller size of the inner wheel 40 compared to the existing one, even if it is smaller than about 65%. Reduces the oil supply flow rate.

Therefore, from the diagram comparing the oil supply flow rate according to application compared to non-application of the roller wheel groove (23a), the roller wheel groove (23a) has a triangular cross-section (A shape), a semicircular cross-section (B shape), and a square cross-section (C It is experimentally proven that the oil supply flow rate is effectively increased or decreased in the order of shape. This is because the greater the resistance generated in the roller wheel groove 23a, the greater the supply flow rate to the cam journal, which is the counterpart part.

Meanwhile, Figure 6 is an example of an engine to which the camshaft lubrication system according to the present invention is applied. As shown, the engine 100 is equipped with a camshaft lubrication system 1 and a CVVD system (Continuously Variable Valve Duration System) 200 on the camshaft 10.

Specifically, the CVVD system 200 controls the arrival of the short/long duration position by rotating a motor (or actuator) controlled by a controller (or engine controller) to control the intake/exhaust valve opening and closing timing. do. Therefore, the CVVD system 200 is composed of a CVVD motor, a Hall sensor/cam sensor, etc. for controlling the CVVD mechanism 200-1, like a typical CVVD system. However, the CVVD system 200 is lubricated with oil from the cam wheel passage 20-3 when the CVVD mechanism part 200-1 is defective in the cam wheel 11 of the cam shaft 10, so that it is a typical CVVD system. and has differences in lubrication structure.

Specifically, the camshaft lubrication system 1 is the same as the camshaft lubrication system 1 described through FIGS. 1 to 5. However, the camshaft lubrication system 1 uses oil from the cam wheel passage 20-3 of the cam wheel 11 of the camshaft 10 to lubricate the CVVD mechanism 200-1 of the CVVD system 200. There is a difference in the supply of oil. In addition, the camshaft lubrication system 1 forms a plurality of cam journals 13 on the camshaft 10 to match the number of engine cylinders, and the cam journals 13 are coupled to the cam journal hub 10-1. There is a difference in that the oil from the cam journal flow path (20-4) is supplied as lubricating oil to the cam journal hub (10-1).

As described above, the engine 100 according to this embodiment has a roller main flow path ( A roller wheel groove (23a) in communication with 21b) is formed in the roller wheel (30), and an inner wheel hole (23b) that sends the oil from the roller wheel groove (23a) toward the needle bearing (50) is formed in the needle bearing (50). ) is formed on the inner wheel 40 surrounded by a camshaft lubrication system (1) in which the roller main passages (21b)/inner wheel holes (23b) are arranged alternately at an angle (K), thereby forming a differential pressure in the passages. The oil flow path of the roller wheel groove (23a)/inner wheel hole (23b) allows adjustment of the amount of lubricating oil supplied without changing the oil hole size, and in particular, the amount of oil supplied can be adjusted to 100% of the engine while maintaining the minimum oil hole processing size. It can be further reduced to meet the needs of the CVVD system 200, and the friction reduction effect is improved by constant oil contact at the mechanism contact area where the CVVD mechanism part 200-1 of the CVVD system 200 is connected.

1: Cam shaft lubrication system 10: Cam shaft
10-1: Cam journal hub 10A: Roller wheel hole
11: Cam heel 11-1: Cam heel housing
13: Cam journal 15: Valve cam
17: Shaft end 20: Oil lubrication line
20-1: Inlet flow path 20-2: Shaft flow path
20-3: Cam wheel flow path 20-4: Cam journal flow path
20-5: Inner wheel flow path 21: Roller wheel flow path
21a: Roller shaft hole 21b: Roller main flow path
21c: roller sub flow path 23: flow control flow path
23a: roller wheel groove 23b: inner wheel hole
30: Roller wheel 30-1,30-2: 1st, 2nd roller wheel
31: roller body 33: roller head
40: Inner wheel 41: Inner wheel body
43: roller wheel pocket 43a: main pocket
43b-1.43b-2: Left and right head pockets
45: Sub-channel 45-1, 45-2: Left, right sub-channel
50: Needle bearing 70: Oil
100: engine
200: CVVD System (Continuously Variable Valve Duration System)
200-1: CVVD mechanism part

Claims (17)

An inner wheel passage for oil supply is formed by an inner wheel surrounding a roller wheel fixed to a camshaft, and the inner wheel passage is arranged in a staggered manner by the angle between the roller wheel passage of the roller wheel and the flow rate control passage of the inner wheel.
A camshaft lubrication system comprising:
The camshaft lubrication system according to claim 1, wherein the included angle is an acute angle.
The method according to claim 1, wherein the roller wheel flow path is made of a roller wheel groove communicating with a roller main flow path drilled in the roller wheel, and the flow rate control flow path is made of an inner wheel hole drilled in the inner wheel to communicate with the roller wheel groove. A camshaft lubrication system characterized in that.
The camshaft lubrication system according to claim 3, wherein the roller main passage and the inner wheel hole form the angle between each other.
The camshaft lubrication system according to claim 3, wherein the roller wheel groove has a path passing through an outlet of the roller main passage.
The camshaft lubrication system according to claim 5, wherein the path of the roller wheel groove is formed at an obtuse angle.
The camshaft lubrication system according to claim 5, wherein the path of the roller wheel groove is dug to a depth where oil from the roller main passage can remain.
The camshaft lubrication system according to claim 7, wherein the depth forms one of a triangular cross-section, a semicircular cross-section, and a square cross-section.
The camshaft lubrication system according to claim 3, wherein the inner wheel hole discharges oil to the outer diameter of the inner wheel and the inner diameter of the needle bearing surrounding the inner wheel.
The camshaft lubrication system according to claim 1, wherein the roller wheel passage is in communication with a shaft passage through which oil flows through a hole drilled inside the shaft body of the cam shaft to supply oil.
The camshaft lubrication method according to claim 10, wherein the shaft passage includes an inflow passage through which oil flows into the shaft passage, and a cam wheel passage through which oil is discharged from the shaft passage, and a cam journal passage communicating with each other at a distance. system.
The camshaft lubrication system according to claim 11, wherein each of the inflow passage, the cam wheel passage, and the cam journal passage is drilled in a radial direction of the cam shaft and is perpendicular to the shaft passage.
A cam shaft with a cam that opens and closes the intake/exhaust valves,
A roller wheel groove communicating with the shaft passage of the camshaft and the roller main passage through which oil from the engine block flows is formed on the roller wheel, and an inner wheel hole is formed to send oil from the roller wheel groove toward the needle bearing. a camshaft lubrication system formed on the inner wheel surrounded by the needle bearing, wherein the roller main flow path and the inner wheel hole are arranged to be staggered at an angle;
A CVVD system (Continuously Variable Valve Duration System) coupled to the camshaft to control the opening and closing of the intake/exhaust valves;
An engine characterized in that it includes.
The engine according to claim 13, wherein the included angle is formed at 15 to 20 degrees.
The engine according to claim 13, wherein the roller wheel groove is dug in the roller wheel in an area of 120 to 150°.
The engine according to claim 13, wherein the CVVD system is lubricated by the camshaft lubrication system.
The engine according to claim 16, wherein the lubrication of the CVVD system is achieved by supplying oil from the inner wheel hole.