VALVE BRIDGE
There is provided herein a valve mechanism for an internal combustion engine comprising a rocker arm and a valve bridge. There is also described herein a valve bridge.
This application claims priority to U.S. Application No. 61/319,022 filed on Mar. 30, 2010, the contents all of which are hereby incorporated by reference in their entirety.
FIELD OF THE INVENTIONThe field of the invention generally relates to a valve bridge and valve bridge mechanism of an internal combustion engine.
BACKGROUND OF THE INVENTIONInternal combustion engines typically actuate valves on engine cylinders using an actuated rocker arm acting through a valve bridge. In operation, for example, a cam shaft-associated push rod actuates the rocker arm, which in turn actuates the valve through the valve bridge. Intake valves admit fuel and air into the cylinder, and exhaust valves allow combustion gas to escape from the cylinder. Valve actuation is required in order for the engine to produce power.
As the rocker arm pivots during engine operation, the rocker arm exerts force upon the valve bridge, which in turn actuates valve movement in a particular cylinder. It is desirable for there to be an efficient transfer of force from the rocker arm to the valve bridge and in turn to the valve stems.
There remains a need for an improved valve engine mechanism and/or valve bridge.
This background information is provided for the purpose of making known information believed by the applicant to be of possible relevance to the present invention. No admission is necessarily intended, nor should it be construed, that any of the preceding information constitutes prior art against the present invention.
SUMMARY OF THE INVENTIONIn an aspect of the present invention there is provided a valve bridge and valve bridge mechanism for an internal combustion engine.
In accordance with one aspect of the present invention there is provided a valve bridge, comprising: a bridge having a joint disposed in a central portion of said bridge; and a pivot member disposed within said joint, said pivot member comprising an abutment surface for cooperative association with a surface on a rocker arm and an outer surface portion configured for rotation within said joint, wherein said bridge is configured to engage two engine valves
In accordance with another aspect of the present invention there is provided a valve bridge, comprising: a bridge having a first joint and a second joint disposed in a central portion of said bridge, said first and second joints are in communication; a first pivot member disposed in said first joint and a second pivot member disposed in said second joint, said first pivot member comprising a first abutment surface for cooperative association with a surface on a rocker arm, a second abutment surface, and an outer surface portion configured for rotation within said first joint, said second pivot comprising an outer surface configured for rotation within said second joint and which cooperates with said second abutment surface of said first pivot member so as to restrain rotation of said first pivot member, wherein said bridge is configured to engage an engine valve.
In accordance with another aspect of the present invention, there is provided a valve bridge, comprising: a bridge having a joint disposed in a central portion of said bridge; an abutment member positioned on the inner surface of said joint; and a pivot member disposed within said joint, said pivot member comprising a first abutment surface for cooperative association with a surface on a rocker arm, an outer surface portion configured for rotation within said joint, and a second abutment surface configured to restrain rotation of said pivot member within said join, wherein said bridge is configured to engage two engine valves.
In accordance with another aspect of the present invention, there is provided a valve train mechanism, comprising: a rocker arm having a joint disposed at a first end of said rocker arm; a pivot member disposed within said joint, said pivot member comprising an abutment surface and an outer surface portion configured for rotation within said joint; and a valve bridge comprising a surface disposed on a central portion of said valve bridge configured for cooperative association with said abutment surface on said pivot member; wherein said bridge is configured to engage an engine valve.
In accordance with another aspect of the present invention, there is provided valve train mechanism, comprising: a rocker arm having a first end comprising a first joint and a second joint disposed at a first end of said rocker arm, said first and second joints are in communication; a first pivot member disposed in said first joint and a second pivot member disposed in said second joint, said first pivot member comprising an first abutment surface, a second abutment surface, and an outer surface portion configured for rotation within said first joint, said second pivot member comprising an outer surface configured for rotation within said second joint and which cooperates with said second abutment surface of said first pivot member so as to restrain rotation of said first pivot member; and a valve bridge comprising a surface in a central portion of said valve bridge, for cooperative association with said first abutment surface of said first pivot member, wherein said valve bridge is configured to engage an engine valve.
Embodiments of the present invention will now be described, by way of example only, with reference to the attached Figures, wherein:
In the Detailed Description that follows, the numbers in bold face type serve to identify the component parts that are described and referred to in relation to the drawings depicting various embodiments of the invention. It should be noted that in describing various embodiments of the present invention, the same reference numerals have been used to identify the same of similar elements. Moreover, for the sake of simplicity, parts have been omitted from some figures of the drawings.
DETAILED DESCRIPTIONInternal combustion engines typically actuate valves on engine cylinders using an actuated rocker arm(s) acting through a valve bridge. In operation, for example, a cam shaft-associated push rod actuates the rocker arm, which in turn actuates the valve through the valve bridge. Intake valves admit fuel and air into the cylinder, and exhaust valves allow combustion gas to escape from the cylinder. Valve actuation is required in order for the engine to produce power.
Referring to the drawings, and as described herein, there is provided a valve bridge and a valve bridge mechanism, operable to actuates the valves of an engine.
Also as referring to the drawings, and as described herein, there is provided a valve bridge and a valve bridge mechanism for an internal combustion engine of the type comprising a rocker arm.
It will be appreciated that a variety of valve trains exist. It will be appreciated that the valve bridge and valve bridge mechanism of the present application may be applied to the other types of valve train.
One embodiment of the present invention is described in
In
As shown in
In the embodiment of
Valve bridge 6 further comprises pivot member 24 disposed in joint 16. Pivot member 24 comprises abutment surface 26 configured for cooperative association with surface 14 on rocker arm 2. Desirably, surface 14 and abutment surface 26 have a complementary shape or configuration which permit cooperative association between pivot member 24 and bridge 32. In a specific example, both abutment surface 26 and surface 14 are generally planar.
Pivot member 24 further comprises curved portion 28 configured so as to permit rotation of pivot member 24 within joint 16. In the example of
As shown in
In
In the example of
Retaining means 200 can be formed in a variety of ways. In one example, the retaining means 200 are machined in place on bridge 32 after pivot member 24 is placed in joint 16.
In another example, retaining means 200 are formed prior to insertion of pivot member 24 in joint 16. In this example, the portion of bridge 32 that defines the aperture of joint 16 is elasto-plastically deformable. The aperture of joint 16 (generally indicated by line d2) as defined by retaining means 200 is sized to be smaller than the diameter pivot member 24 (generally indicated by line d1). Pivot member 24 is pushed through the elasto-plastically deformable aperture defined by retaining means 200 so as to place pivot member 24 within joint 16. Insertion of pivot member 24 causes the elasto-plastically deformable material to deform and reform (the elastic component of the deformation is recovered after the passage of the pivot member) once pivot member 24 is inserted. Thus, once pivot member 24 is inserted, retaining means 200 reform to their initial size, and thereby reduce the size of the aperture so as to re-form retaining means 200. Following insertion of pivot member 24 the resulting aperture defined by retaining means 200 (generally indicated by line d2) is smaller than the diameter of pivot member 24 (generally indicated by line d1). The size and/or shape of joint 16 remains sufficient to permit rotation of pivot member 24 within joint 16.
In the specific example of
In operation, pivot member 24 pivots in joint 16 around inner surface 30 as rocker arm 2 is actuated. It will be understood that pivot member 24 rotates freely and moves within joint 16 so as to translate the force of rocker arm 2 into valve bridge 6 during engine operation.
Thus, as rocker arm 2 pivots during engine operation, rocker arm 2 exerts force on valve bridge 6, which in turn actuates valve movement in a cylinder (not shown).
In some examples, operative association of a cam shaft though, for example, a cam follower, pushrod, and the like, results in repeated movement of rocker arm 2 so as to cause a swinging movement of rocker arm 2.
The pivoting movement of rocker arm 2 alternatively exerts a force on valve bridge 6. As rocker arm 2 pivots, surface 14 of rocker arm 2 associates with abutment surface 26 of pivot member 24 so as translate the force from rocker arm 2 to bridge 32, so as to and causes valves, which are in contact with valve bridge 6 on their stem, to open. Thus, rotation of pivot member 24 within joint 16 permits the vertical motion of rocker arm 2 to be translated into bridge 32 during engine operation. In some examples, when rocker arm 2 is released, the valves are pushed up by the force of valve-shutting springs and close.
The valve bridge and valve bridge mechanism of the present invention enables the rocker arm to operate two valves simultaneously.
An alternate embodiment of valve bridge 6 is depicted in
In
Valve bridge 6 further comprises first pivot member 104 disposed in first joint 100 and second pivot member 120 disposed in second joint 102.
First pivot member 104 comprises first abutment surface 106 which cooperates with surface 14 on rocker arm 2. In a specific example, both first abutment surface 106 and surface 14 are generally planar. The complementary shape of first abutment surface 106 and surface 14 facilitate cooperation between the two parts. First pivot member 104 further comprises second abutment surface 108. In the example of
As shown in
As shown in
In one example outer surface 122 is configured so as to permit rotation of second pivot member 120 within second joint 102. In another example, pivot member 120 does not rotate within second joint 102.
Second joint 102 comprises second inner surface 130, which comprises generally planar surfaces. Inner surface 130 comprises walls 130a and generally conical walls 130b.
Pivot member 120 can be a variety of shapes, so long as pivot member 120 is able to cooperate with second abutment surface 108 and restrain rotation of first pivot member 104. The restraint to the rotation of first pivot member 104 helps preventing or minimizing miss assembly of valve bridge 6 in the engine. It will be appreciated that the restraint to rotation of first pivot member 104 does not interfere with the rotation of first pivot member 104 within the angle of rotation required during normal engine operation.
Second pivot member 120 can be made from a variety of materials, including but not limited to steel, cast iron or aluminium.
As with the example of
In one example, said retaining means are disposed at the aperture of said joint; the aperture of joint 100 defined by retaining means is smaller than the diameter of pivot member 104 and so retains pivot member 104 within first joint 100.
Retaining means can be formed in a variety of ways. In one example, the retaining means are machined in place on bridge 32 after pivot member 104 is placed in first joint 100.
In another example, retaining means are formed prior to insertion of pivot member 104 in joint 100. In this example, the portion of bridge 32 that defines the aperture of joint 100 is elasto-plastically deformable. The aperture of joint 100 as defined by retaining means is sized to be smaller than the diameter pivot member 104. Pivot member 104 is pushed through the elasto-plastically deformable aperture defined by retaining means so as to place first pivot member 104 within first joint 100. Insertion of pivot member 104 causes the elasto-plastically deformable material to deform and reform (the elastic component of the deformation is recovered after the passage of the pivot member) once pivot member 104 is inserted. Thus, once pivot member 104 is inserted, retaining means reform to their initial size, and thereby reduce the size of the aperture so as to re-form retaining means. Following insertion of pivot member 104 the resulting aperture defined by retaining means is smaller than the diameter of pivot member 104. The size and/or shape of joint 100 remains sufficient to permit rotation of pivot member 104 within joint 100.
In
Valve bridge 6 further comprises first pivot member 104 disposed in first joint 100.
First pivot member 104 comprises first abutment surface 106 which cooperates with surface 14 on rocker arm 2. In a specific example, both first abutment surface 106 and surface 14 are flat. The complementary shape of first abutment surface 106 and surface 14 facilitate cooperation between the two parts. First pivot member 104 further comprises second abutment surface 108. In the example of
As shown in
As shown in
Outer surface 302 of second abutment member 300 is generally curved and cooperates with second abutment surface 108 of first pivot member 104. Abutment member 300 can be a variety of shapes, so long as abutment member 300 is able to cooperate with second abutment surface 108 and restrain rotation of first pivot member 104. The restraint to the rotation of first pivot member 104 helps preventing or minimizing miss assembly of valve bridge 6 in the engine.
As with the previous examples of in another example, in the embodiment of
In one example, said retaining means are disposed at the aperture of said joint; the aperture of joint 100 defined by retaining means is smaller than the diameter of pivot member 104 and so retains pivot member 104 within first joint 100.
Retaining means can be formed in a variety of ways. In one example, the retaining means are machined in place on bridge 32 after pivot member 104 is placed in first joint 100.
In another example, retaining means are formed prior to insertion of pivot member 104 in joint 100. In this example, the portion of bridge 32 that defines the aperture of joint 100 is elasto-plastically deformable. The aperture of joint 100 as defined by retaining means is sized to be smaller than the diameter pivot member 104. Pivot member 104 is pushed through the elasto-plastically deformable aperture defined by retaining means so as to place first pivot member 104 within first joint 100. Insertion of pivot member 104 causes the elasto-plastically deformable material to deform and reform (the elastic component of the deformation is recovered after the passage of the pivot member) once pivot member 104 is inserted. Thus, once pivot member 104 is inserted, retaining means reform to their initial size, and thereby reduce the size of the aperture so as to re-form retaining means. Following insertion of pivot member 104 the resulting aperture defined by retaining means is smaller than the diameter of pivot member 104. The size and/or shape of joint 100 remains sufficient to permit rotation of pivot member 104 within joint 100.
In operation, first pivot member 104 pivots around first inner surface 112 of first joint 100 as rocker arm 2 is actuated. It will be understood first pivot member 104 rotates and moves within first joint 100 so as to translate the force of rotation and translation during operation into the valve bridge during engine operation. For example,
It will be appreciated that the location of joint 16, first joint 100 and second joint 102 in the center portion of bridge 32 results in the equalization of the force applied to valve stems 22,22′, which is preferable as it can result decreased wear of the valve stems and increased life of valve stems (as compared to uneven force distribution to the valve stems). Joint 16, first joint 100 and second joint 102 and may be cast as part of bridge 32 or drilled into bridge 32. In one example, joint 16, first joint 100 and second joint 102 are cold formed in bridge 32. The configuration of the top and bottom surfaces of bridge 32 will be determined by the intended use, manufacturing considerations and/or engine application.
In another example, joint 16, first joint 100 and second joint 102 are configured to hold lubrication within the joint, so as to reduce the friction between the pivot member and joint during engine operation. Such lubrication can include engine oil or the like.
In another example of the present invention, the lash setting is made with a shim inserted between bridge 32 and rocker arm 2, which is facilitated as both abutment surface 26 and surface 14 are generally flat.
Alternate embodiments of the present invention are described in
In
One embodiment is shown in
As shown in
In the embodiment of
Rocker arm 1002 further comprises pivot member 1024 disposed in joint 1016. Pivot member 1024 comprises abutment surface 1026 configured for cooperative association with surface 1014 on bridge 1032. Desirably, surface 1014 and abutment surface 1026 have a complementary shape or configuration which permits cooperative association between pivot member 1024 and bridge 1032. In a specific example, both abutment surface 1026 and surface 1014 are generally planar.
Pivot member 1024 further comprises curved portion 1028 configured so as to permit rotation of pivot member 1024 within joint 1016. In the example of
As shown in
In
In operation, pivot member 1024 pivots in joint 1016 around inner surface 1030 as rocker arm 1002 is actuated. It will be understood that pivot member 1024 rotates freely and moves within joint 1016 so as to translate the force of rocker arm 1002 into valve bridge 1006 during engine operation.
Thus, as rocker arm 1002 pivots during engine operation, rocker arm 1002 exerts force on valve bridge 1006, which in turn actuates valve movement in a cylinder (not shown).
In some examples, operative association of a cam shaft though, for example, a cam follower, pushrod, and the like, at the second end of rocker arm 1002 results in repeated movement of rocker arm 1002 so as to cause a swinging movement of rocker arm 1002.
The pivoting movement of rocker arm 1002 alternatively exerts a force on valve bridge 1006. As rocker arm 1002 pivots, abutment surface 1026 of pivot member 1024 in joint 1016 of rocker arm 1002 associates with surface 1014 of bridge 1032 so as translate the force from rocker arm 1002 to bridge 32, so as to and causes valves, which are in contact with valve bridge 1006 on their stem, to open. Thus, rotation of pivot member 1024 within joint 1016 permits the vertical motion of rocker arm 1002 to be translated into bridge 1032 during engine operation. In some examples, when rocker arm 1002 is released, the valves are pushed up by the force of valve-shutting springs and close.
The valve bridge and valve bridge mechanism of the present invention enables the rocker arm to operate two valves simultaneously.
An alternate embodiment is depicted in
In
In the embodiment of
Rocker arm 1002 further comprises first pivot member 100104 disposed in first joint 100100 and second pivot member 100120 disposed in second joint 100102.
First pivot member 100104 comprises first abutment surface 100106 which cooperates with surface 1014 on bridge 1032 In a specific example, both first abutment surface 100106 and surface 1014 are generally planar. The complementary shape of first abutment surface 100106 and surface 1014 facilitate cooperation between the two parts. First pivot member 100104 further comprises second abutment surface 100108. In the example of
As shown in
As shown in
In one example, outer surface 100122 is configured so as to permit rotation of second pivot member 100120 within second joint 100102. In another example, pivot member 100120 does not rotate within second joint 100102.
Second joint 100102 comprises second inner surface 100130, which comprises generally planar surfaces. Inner surface 100130 comprises walls 100130a and generally conical base 100130b.
Second pivot member 100120 can be a variety of shapes, so long as second pivot member 100120 is able to cooperate with second abutment surface 100108 and restrain rotation of first pivot member 100104. The restraint to the rotation of first pivot member 100104 helps in preventing or minimizing miss assembly in the engine. It will be appreciated that the restraint to rotation of first pivot member 100104 does not interfere with the rotation of first pivot member 100104 within the angle of rotation required during normal engine operation.
Second pivot member 100120 can be made from a variety of materials, including but not limited to steel, cast iron or aluminium.
As with the previous examples, and in the embodiments of
In one example, said retaining means are disposed at the aperture of said joint; the aperture of joint 1016 or first joint 100100 defined by retaining means is smaller than the diameter of pivot member 1024 or first pivot member 100104 and so retains pivot member 1024 or first pivot member 100104 within joint 1016 or first joint 100100, respectively.
Retaining means can be formed in a variety of ways. In one example, the retaining means are machined in place on rocker arm 1002 after pivot member 1024 or first pivot member 100104 is placed in joint 1016 or first joint 100100, respectively.
In another example, retaining means are formed prior to insertion of pivot member 1024 or first pivot member 100104 in joint 1016 or first joint 100100, respectively. In this example, the portion of rocker arm 1002 that defines the aperture of joint 1016 or first joint 100100 is elasto-plastically deformable. The aperture of joint 1016 or first joint 100100 as defined by retaining means is sized to be smaller than the diameter of pivot member 1024 or first pivot member 100104, respectively. Pivot member 1024 or first pivot member 100104 is pushed through the elasto-plastically deformable aperture defined by retaining means so as to place pivot member 1024 or first pivot member 100104 within joint 1016 or first joint 100100, respectively. Insertion of pivot member 1024 or first pivot member 100104 causes the elasto-plastically deformable material to deform and reform (the elastic component of the deformation is recovered after the passage of the pivot member) once pivot member 1024 or first pivot member 100104 is inserted. Thus, once pivot member 1024 or first pivot member 100104 is inserted, retaining means reform to their initial size, and thereby reduce the size of the aperture so as to re-form retaining means. Following insertion of pivot member 1024 or first pivot member 100104 the resulting aperture defined by retaining means is smaller than the diameter of pivot member 1024 or first pivot member 100104. The size and/or shape of joint 1016 or first joint 100100 remains sufficient to permit rotation of pivot member 1024 or first pivot member 100104, respectively, within joint 1016 or first joint 100100.
It will be appreciated the valve bridge and valve bridge mechanism as described herein can be used in a variety of internal combustion engines. For example, the valve bridge and valve bridge mechanism as described herein may be used in a 4-stroke cycle engine.
All publications, patents and patent applications mentioned in this Specification are indicative of the level of skill those skilled in the art to which this invention pertains and are herein incorporated by reference to the same extent as if each individual publication patent or patent application was specifically and individually indicated to be incorporated by reference.
The invention being thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modification as would be obvious to one skilled in the art are intended to be included within the scope of the following claims.
Claims
1. A valve bridge, comprising: a bridge having a joint disposed in a central portion of said bridge; and a pivot member disposed within said joint, said pivot member comprising an abutment surface for cooperative association with a surface on a rocker arm and an outer surface portion configured for rotation within said joint, wherein said bridge is configured to engage two engine valves.
2. The valve bridge of claim 1, wherein the inner surface of said joint is generally U-shaped comprising a generally cylindrical wall and a curved base.
3. The valve bridge of claim 1, wherein the inner surface of said joint comprises (i) generally planar walls and a generally conical base, (ii) a generally conical base, or (iii) a generally curved base.
4. The valve bridge of claim 1, further comprising retaining means configured to retain said pivot member with said joint.
5. The valve bridge of claim 4, wherein said retaining means are disposed at the aperture of said joint.
6. The valve bridge of claim 4, wherein said retaining means define an aperture in said joint which is less than the diameter of said pivot member.
7. A valve bridge, comprising: a bridge having a first joint and a second joint disposed in a central portion of said bridge, said first and second joints are in communication; a first pivot member disposed in said first joint and a second pivot member disposed in said second joint, said first pivot member comprising a first abutment surface for cooperative association with a surface on a rocker arm, a second abutment surface, and an outer surface portion configured for rotation within said first joint, said second pivot member comprising an outer surface configured for rotation within said second joint and which cooperates with said second abutment surface of said first pivot member so as to restrain rotation of said first pivot member, wherein said bridge is configured to engage an engine valve.
8. The valve bridge of claim 7, wherein the inner surface of said first joint comprises generally planar walls and a generally conical base.
9. The valve bridge of claim 7, further comprising retaining means configured to retain said pivot member with said first joint.
10. The valve bridge of claim 9, wherein said retaining means are disposed at the aperture of said joint.
11. The valve bridge of claim 9, wherein said retaining means define an aperture in said joint which is less than the diameter of said pivot member.
12. The valve bridge of claim 7, wherein said bridge further comprises a conduit in communication with said second joint and the outer surface of said bridge.
13. A valve bridge, comprising: a bridge having a joint disposed in a central portion of said bridge; an abutment member positioned on the inner surface of said joint; and a pivot member disposed within said joint, said pivot member comprising a first abutment surface for cooperative association with a surface on a rocker arm, an outer surface portion configured for rotation within said joint, and a second abutment surface configured to restrain rotation of said pivot member within said join, wherein said bridge is configured to engage an engine valve.
14. The valve bridge of claim 13, wherein said abutment member comprised a generally curved outer surface adapted for cooperative association with said second abutment surface of said pivot member.
15. The valve bridge of claim 13, further comprising retaining means configured to retain said pivot member with said first joint.
16. The valve bridge of claim 15, wherein said retaining means are disposed at the aperture of said joint.
17. The valve bridge of claim 16, wherein said retaining means define an aperture in said joint which is less than the diameter of said pivot member.
18. A valve train mechanism, comprising: a rocker arm having a joint disposed at a first end of said rocker arm; a pivot member disposed within said joint, said pivot member comprising an abutment surface and an outer surface portion configured for rotation within said joint; and a valve bridge comprising a surface disposed on a central portion of said valve bridge configured for cooperative association with said abutment surface on said pivot member; wherein said bridge is configured to engage two engines valves.
19. The valve train mechanism of claim 18, wherein the inner surface of said joint is generally U-shaped comprising a generally cylindrical wall and a curved base.
20. The valve train mechanism of claim 18, further comprising retaining means configured to retain said pivot member with said joint.
21. The valve train mechanism of claim 20, wherein said retaining means are disposed at the aperture of said joint.
22. A valve train mechanism, comprising: a rocker arm having a first end comprising a first joint and a second joint disposed at a first end of said rocker arm, said first and second joints are in communication; a first pivot member disposed in said first joint and a second pivot member disposed in said second joint, said first pivot member comprising an first abutment surface, a second abutment surface, and an outer surface portion configured for rotation within said first joint, said second pivot member comprising an outer surface configured for rotation within said second joint and which cooperates with said second abutment surface of said first pivot member so as to restrain rotation of said first pivot member; and a valve bridge comprising a surface in a central portion of said valve bridge, for cooperative association with said first abutment surface of said first pivot member, wherein said valve bridge is configured to engage an engine valve.
23. The valve train mechanism of claim 22, further comprising retaining means configured to retain said first pivot member with said first joint.
24. The valve train mechanism of claim 23, wherein said retaining means are disposed at the aperture of said joint.
25. The valve train mechanism of claim 22, wherein said rocker arm further comprises a conduit in communication with said second joint and the outer surface of said rocker arm.
Type: Application
Filed: Mar 29, 2011
Publication Date: Oct 6, 2011
Applicant: GNUTTI LTD. (Huron Park)
Inventor: Antonio Gigante (London)
Application Number: 13/074,755
International Classification: F01L 1/26 (20060101);