Valve rocker arm

Abstract

The present invention relates to a valve rocker arm. The valve rocker arm comprises a rocker arm housing, a rotating member for engaging a driving mechanism, and a pin, wherein the pin passes through mounting holes on the rocker arm housing and the rotating member at the same time, thereby rotatably mounting the rotating member on the rocker arm housing, and the rocker arm housing has an oil supply hole leading to the pin, wherein the pin has an oil groove formed on the circumferential outer surface, the oil groove has a first section contacting the inner wall of the mounting hole of the rocker arm housing and a second section contacting the inner wall of the mounting hole of the rotating member, and the oil supply hole is connected to the oil groove, and the valve rocker arm also includes a seal, which is mounted on the circumferential outer surface of the pin and covers the oil groove from the radial outer side in the connection area between the first section and the second section, thereby preventing the liquid passing through the oil groove from leaking from the gap between the housing and the rotating member. The lubrication structure of the valve rocker arm of the present invention is simple and easy to manufacture.

Description

Technical Field

[0001] The present invention relates to the technical field of engines, and in particular to a valve rocker arm for a valve mechanism of an engine. Background Art

[0002] In existing vehicle internal combustion engines, a valve system is generally provided, and therefore a valve rocker arm is provided to convert the rotational motion of the cam into the linear motion of driving the valve push rod. The side surface of the cam abuts against the valve rocker arm, so that the valve rocker arm can swing under the drive of the cam. In order to reduce the friction between the rotating cam and the valve rocker arm, a rotating member is usually provided in the valve rocker arm to abut the cam, so that the sliding friction between the cam and the valve rocker arm can be converted into rolling friction between the cam and the rotating member. The rotating member is mounted on the rocker arm housing by a pin, and there is a lot of friction between the pin and the inner hole of the rotating member. Therefore, a lubrication structure needs to be provided in the rocker arm housing to supply lubricating oil to the contact surface between the pin and the rotating member.

[0003] For example, CN 107654269 A discloses a valve rocker arm with a typical lubrication structure. The valve rocker arm has a segmented oil groove formed in the pin. The oil groove for lubricating the inner surface of the roller is formed in the axial middle of the pin. In order to guide the lubricating oil to the oil groove in the middle, it is necessary to set an inclined oil hole connected to the oil groove in the middle. Such an inclined oil hole is very difficult to process, which results in an increase in the defective rate and manufacturing cost. Summary of the invention

[0004] Therefore, the technical problem to be solved by the present invention is to provide a valve rocker arm with a simple lubrication structure.

[0005] The above technical problems are solved by a valve rocker arm according to the present invention. The valve rocker arm comprises a rocker arm housing, a rotating member for engaging a driving mechanism, and a pin, the pin simultaneously passing through mounting holes on the rocker arm housing and the rotating member, so as to rotatably mount the rotating member on the rocker arm housing, the rocker arm housing having an oil supply hole leading to the pin, wherein the pin has an oil groove formed on the circumferential outer surface, the oil groove having a first section contacting the inner wall of the mounting hole of the rocker arm housing and a second section contacting the inner wall of the mounting hole of the rotating member, the oil supply hole being connected to the oil groove, and the valve rocker arm further comprising a seal, the seal being mounted on the circumferential outer surface of the pin and covering the oil groove from the radial outer side in the connection area between the first section and the second section, so as to prevent the liquid passing through the oil groove from leaking from the gap between the housing and the rotating member. In this design, the oil groove formed on the pin surface is used to replace the segmented oil hole formed inside the pin in the prior art, and the seal is added to prevent the liquid from leaking from the gap between the rocker arm housing and the rotating member, which significantly simplifies the lubrication structure and is very easy to manufacture, thereby greatly reducing the production cost.

[0006] According to a preferred embodiment of the present invention, the oil groove can extend in a straight line along the axial direction of the pin, which enables the oil groove to extend to a shorter length and facilitates turning processing.

[0007] According to another preferred embodiment of the present invention, the oil groove extends from the position corresponding to the opening of the oil supply hole to the position corresponding to the axial middle of the rotating part. This means that the end of the oil groove will not extend to the end of the pin, and in the case where the rotating part is installed between the two side walls of the rocker arm housing, the oil groove only needs to extend from the position corresponding to the oil supply hole of one side wall to the middle of the rotating part, and will not extend to the other end of the rotating part or the position of the other side wall. Further preferably, the oil groove can extend beyond the axial midpoint of the rotating part, for example, to a position of three quarters of the axial length of the rotating part, so that there is a sufficiently large contact length between the rotating part and the oil groove, which is convenient for fully lubricating the rotating part.

[0008] According to another preferred embodiment of the present invention, the pin may have a mounting groove surrounding its circumferential outer surface, and the seal is installed in the mounting groove. The seal can be conveniently fixed by matching the shape of the seal with the mounting groove, and the annular mounting groove can be formed by a turning process, which is easy to process. In this case, the seal can preferably be an annular plate having a notch in the circumferential direction, such as a metal plate. The notch on the annular plate allows the seal to deform elastically, which facilitates the installation of the seal into the annular mounting groove by snap-fitting. Further preferably, the axial sides of the seal can be interference-fitted with the mounting groove to ensure the stability of the installation. In addition, the radial outer surface of the seal installed in the mounting groove is flush with the radial outer surface of the pin, and in particular, the radial thickness of the seal can be equal to the radial depth of the mounting groove, so that the seal does not interfere with the installation of the pin with the rocker arm housing and the rotating member and fits tightly with the mounting groove, thereby ensuring the sealing effect.

[0009] According to another preferred embodiment of the present invention, the pin may have a positioning hole formed on the axial end face, the positioning hole is a blind hole that is not connected to the oil groove, and when viewed in a radial plane, the positioning hole is aligned with the oil groove in the radial direction. This means that when viewed in a radial plane, the extension of the line between the positioning hole and the oil groove passes through the center of the circular cross section of the pin. This makes it possible to locate the circumferential position of the oil groove by observing the position of the positioning hole on the end face when installing the pin, thereby facilitating the alignment of the oil groove with the oil supply hole. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] The present invention is further described below in conjunction with the accompanying drawings. The same reference numerals in the drawings represent elements with the same functions.

[0011] Figure 1 is a partial cross-sectional view of a valve rocker arm according to an embodiment of the present invention;

[0012] Figure 2is a partial cross-sectional view of a valve rocker arm according to an embodiment of the present invention; and

[0013] Figure 3 is a perspective view of a pin and a seal of a valve rocker arm according to an embodiment of the present invention. DETAILED DESCRIPTION

[0014] The following detailed description and drawings are used to illustrate the principle of the present invention. The present invention is not limited to the preferred embodiments described. The protection scope of the present invention is defined by the claims.

[0015] According to an embodiment of the present invention, a valve rocker arm for a valve mechanism of an engine is provided. The valve rocker arm comprises a rocker arm housing 1 , a wheel-shaped rotating member 2 and a cylindrical pin 3 . Figure 1 FIG. 2 shows a partial cross-sectional view of the valve rocker arm at the position of the rotating member 2. Figure 1 As shown, the rocker housing 1 has two parallel side walls 11 and 12, and the side walls 11 and 12 are respectively formed with circular mounting holes aligned with each other. The rotating member 2 for abutting the driving mechanism (such as a cam, not shown) is installed between the side walls 11 and 12, and its axial direction is aligned with the mounting holes on the two side walls. The pin 3 passes through the mounting holes on the side wall 11, the rotating member 2 and the side wall 12 in sequence, so that the rotating member 2 is rotatably mounted on the rocker housing 1. The pin 3 and the mounting hole of the rocker housing 1 are generally interference fit, so that the pin 3 will not rotate relative to the rocker housing 1. The rocker housing 1 is formed with an oil supply hole 4 on one side of the side wall 11, and the oil supply hole 4 extends perpendicular to the axial direction of the pin 3 and is connected to the mounting hole in the side wall 11. An oil groove 5 is formed on the circumferential outer surface of the pin 3, and the oil groove 5 extends linearly along the axial direction of the pin 3.

[0016] like Figure 2 As shown in the partial cross-sectional view of the valve rocker arm, when the pin 3 is installed in the rocker arm housing 1 and the rotating member 2, the oil groove 5 is aligned with the opening of the oil supply hole 4 in the circumferential direction, and one end of its extension range corresponds to the opening position of the oil supply hole 4 (or it can extend slightly beyond the oil supply hole 4 in the end direction, but cannot extend to the end), and the other end ends at the axial middle area of ​​the rotating member 2 and preferably exceeds the axial midpoint of the rotating member 2, for example, ends at a position of three quarters of the axial length of the rotating member 2. Figure 2 As shown by the dotted line in FIG. 1 , the oil groove 5 can be divided into two sections with the gap between the rocker housing 1 and the rotating member 2 as the dividing line: the first section 51 on the left is the area in contact with the rocker housing 1, and the second section 52 on the right is the area in contact with the rotating member 2. The lubricating oil flowing in from the oil supply hole 4 can flow to the rotating member 2 through the oil groove 5, thereby lubricating the inner surface of the rotating member 2.

[0017] In order to prevent the lubricating oil flowing through the oil groove 5 from leaking from the gap between the rocker arm housing 1 and the rotating member 2, a seal 6 is provided in the connection area between the first section 51 and the second section 52 to cover the oil groove 5 from the radial outside of the oil groove 5. Figure 3 As shown, the seal 6 is an annular plate with a notch, which is installed in the annular mounting groove 7 on the pin 3 in a shape-fitting manner. The mounting groove 7 can be an annular groove with a flat bottom surface formed by turning. The two side walls of the mounting groove 7 form an interference fit with the two sides of the seal 6, so that the seal 6 is firmly fixed in the mounting groove 7. The seal 6 can be formed by bending a metal plate, and its notch allows the seal 6 to be snapped into the mounting groove 7 by elastic deformation. The radial inner surface of the seal 6 can fit tightly against the bottom surface of the mounting groove 7, and the radial thickness of the seal 6 can be equal to the radial depth of the mounting groove 7, so that the radial outer surface of the seal 6 is flush with the radial outer surface of the pin 3. In this way, the seal 6 will not protrude out of the mounting groove 7, avoiding interference with the installation of the pin 3 with the rocker arm housing 1 and the rotating member 2, and the radial outer surface of the seal 6 will also fit the inner wall of the mounting hole, thereby ensuring the sealing effect.

[0018] like Figure 2 and Figure 3 As shown, a positioning hole 8 is also formed on the axial end face of the pin 3. The positioning hole 8 is a blind hole that is not connected to the oil groove 5. When viewed in a radial plane, the positioning hole 8 is aligned with the oil groove 5 in the radial direction. In other words, the extension line of the connecting line of the two in the radial plane passes through the center of the circular cross section of the pin 3. When installing the pin 3, the circumferential position of the oil groove 5 can be determined by the positioning hole 8, so as to facilitate the alignment of the oil groove 5 with the opening of the oil supply hole 4.

[0019] Although possible embodiments are described by way of example in the above description, it should be understood that there are still a large number of variations of embodiments through the combination of all known and other technical features and embodiments that are easily conceivable to the skilled person. It should also be understood that the exemplary embodiment is only an example and that such an embodiment in no way limits the scope of protection, application and configuration of the present invention. The above description is more to provide the skilled person with a technical guide for converting at least one exemplary embodiment, wherein various changes can be made, especially changes in the functions and structures of the components, as long as they do not depart from the scope of protection of the claims.

[0020] Reference numerals list

[0021] 1 Rocker arm housing

[0022] 11 Sidewall

[0023] 12 Sidewall

[0024] 2 Rotating parts

[0025] 3 Pins

[0026] 4 Oil supply hole

[0027] 5 Oil tank

[0028] 51 First Section

[0029] 52 Second Section

[0030] 6 Seals

[0031] 7 Mounting slot

[0032] 8 Positioning holes

Claims

1. A valve rocker arm, comprising a rocker arm housing (1), a rotating member (2) for engaging a driving mechanism, and a pin (3), wherein the pin (3) passes through mounting holes on the rocker arm housing (1) and the rotating member (2) at the same time, so that the rotating member (2) is rotatably mounted on the rocker arm housing (1), and the rocker arm housing (1) has an oil supply hole (4) leading to the pin (3), It is characterized in that The pin (3) has an oil groove (5) formed on the circumferential outer surface, the oil groove (5) has a first section (51) in contact with the inner wall of the mounting hole of the rocker arm housing (1) and a second section (52) in contact with the inner wall of the mounting hole of the rotating member (2), the oil supply hole (4) is connected to the oil groove (5), and the valve rocker arm also includes a seal (6), which is installed on the circumferential outer surface of the pin (3) and covers the oil groove (5) from the radial outside in the connection area between the first section (51) and the second section (52), thereby preventing the liquid passing through the oil groove (5) from leaking from the gap between the rocker arm housing (1) and the rotating member (2).

2. The valve rocker arm according to claim 1, It is characterized in that The oil groove (5) extends linearly along the axial direction of the pin (3).

3. The valve rocker arm according to claim 1, It is characterized in that The oil groove (5) extends from a position corresponding to the opening of the oil supply hole (4) to a position corresponding to the axial middle of the rotating member (2).

4. The valve rocker arm according to claim 3, It is characterized in that The oil groove (5) extends beyond the axial midpoint of the rotating member (2).

5. The valve rocker arm according to claim 1, It is characterized in that The pin (3) has a mounting groove (7) surrounding its circumferential outer surface, and the sealing member (6) is mounted in the mounting groove (7).

6. The valve rocker arm according to claim 5, It is characterized in that The sealing member (6) is an annular plate member having a notch in the circumferential direction.

7. The valve rocker arm according to claim 6, It is characterized in that The sealing element (6) is made of a metal sheet.

8. The valve rocker arm according to claim 5, It is characterized in that Both axial sides of the sealing member (6) are interference fit with the mounting groove (7).

9. The valve rocker arm according to claim 5, It is characterized in that The radial outer surface of the seal (6) installed in the installation groove (7) is flush with the radial outer surface of the pin (3).

10. The rocker arm according to any one of claims 1 to 9, It is characterized in that The pin (3) has a positioning hole (8) formed on the axial end surface, the positioning hole (8) is a blind hole not connected to the oil groove (5), and when viewed in a radial plane, the positioning hole (8) is aligned with the oil groove (5) in the radial direction.

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