US3678906A - Damped valve train system - Google Patents
Damped valve train system Download PDFInfo
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- US3678906A US3678906A US95220A US3678906DA US3678906A US 3678906 A US3678906 A US 3678906A US 95220 A US95220 A US 95220A US 3678906D A US3678906D A US 3678906DA US 3678906 A US3678906 A US 3678906A
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01L—CYCLICALLY OPERATING VALVES FOR MACHINES OR ENGINES
- F01L1/00—Valve-gear or valve arrangements, e.g. lift-valve gear
- F01L1/12—Transmitting gear between valve drive and valve
- F01L1/14—Tappets; Push rods
- F01L1/16—Silencing impact; Reducing wear
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01L—CYCLICALLY OPERATING VALVES FOR MACHINES OR ENGINES
- F01L13/00—Modifications of valve-gear to facilitate reversing, braking, starting, changing compression ratio, or other specific operations
- F01L13/0015—Modifications of valve-gear to facilitate reversing, braking, starting, changing compression ratio, or other specific operations for optimising engine performances by modifying valve lift according to various working parameters, e.g. rotational speed, load, torque
- F01L2013/0089—Modifications of valve-gear to facilitate reversing, braking, starting, changing compression ratio, or other specific operations for optimising engine performances by modifying valve lift according to various working parameters, e.g. rotational speed, load, torque with means for delaying valve closing
Definitions
- ABSTRACT A valve train having a damping means acting on one of the valve train elements prior to valve closing to reduce valve toss" or bounce" characteristically present at exceptionally high engine speeds.
- the damping means may comprise a hydraulic or pneumatic device having a collapsible chamber from which flow is restricted and which reduces the velocity 0 the valve train elements just prior to valve closing.
- valve bounce or valve toss
- This invention provides a valve train construction in which valve bounce is substantially eliminated. Further, it provides a valve train construction in which the closing velocities of the valves are reduced in magnitude just prior to closing impact. The invention also provides a valve train construction in which valve and valve spring life are significantly increased. Still further, this invention provides a damped valve train construction which may be incorporated into conventional internal combustion engines and which may be economically produced.
- a damped valve constructed in accordance with this invention comprises elements including a valve reciprocably mounted within an engine cylinder head that opens and closes a port formed within the cylinder head, a rocker arm pivotally mounted to the cylinder head and engagable with the valve, and a push rod engagable with the rocker arm to transmit motion thereto, a spring biasing the valve toward a closed position, and damping means opposing the spring and engagable with one of the above valve train elements to retard closing and to reduce the valve closing velocity.
- FIG. 1 is a transverse cross sectional view of a cylinder head and valve train illustrating a bolt-on type damper mechanism engagable with the rocker arm.
- FIG. 2 is a transverse cross sectional view of a cylinder head and valve train showing an in-head mounted damper mechanism engagable with the rocker arm.
- FIG. 1 of the drawings shows a preferred embodiment of the invention having a cylinder head 11 formed with an intake passage 12 leading from the intake manifold (not shown) to a combustion chamber (not shown).
- a poppet valve 13 is slidably mounted within a bore 14 formed within the cylinder head. The valve is axially movable to open and close an intake valve port 16. Compressed between the cylinder head at 17 and a retainer 18 is spring 19 which urges the valve toward a closed position.
- the retainer is secured to the end of the valve stem by a pair of locks 21 that engage a groove 22 in the end of the valve 13.
- a rocker arm 23 is connected to the cylinder head 11 by stud 24.
- the rocker arm has a concave cylindrical surface 27 on a fulcrum seat 28, retained to stud 24 by nut 29.
- the rocker arm surface 26 and the fulcrum seat surface 27 determine an axis about which the rocker arm pivots.
- the end of the rocker arm opposite of the valve engages a push rod 31 which transmits motion from the engine camshaft and a tappet (both not shown) to the rocker arm.
- the description to this point describes a generally conventional internal combustion engine construction.
- a damper or dashpot mechanism 32 is secured to the cylinder head 11 by capscrew 33.
- the damper 32 includes an arm 34 positioned adjacent the rocker arm 23 and having a blind bore 36 coaxial with the valve 13.
- a passage 37 is drilled in the arm which communicates with the pressurized lubrication circuit of the engine and provides oil to the bore 36.
- a generally hollow piston 38 is slidably and sealingly received within bore 36 and forms, in cooperation with the bore, a variable volume chamber 39. Compression spring 41 biases the piston 38 toward its maximum extended position in which it abuts retaining ring 42.
- a one-way check valve assembly 42 permits the flow of oil from the internal lubrication passage 37 through port or passage 43 into chamber 39 when the chamber is not under compression.
- the valve assembly includes a perforated cage 45 which retains a ball 44 adjacent port 43. Upon initial compression of the chamber, ball 44 seats in port 43 to close valve 42. Further compression forces oil in a relatively restricted flow through a vent passage 46. A small clearance may be provided between piston 38 and bore 36 permitting a restricted flow of oil to be forced between the piston and bore during chamber compression.
- Piston 38 includes a protruding end 47 adjacent the rocker arm 23 which is spaced from the rocker arm at all times except for a short time prior to and after closure of valve 13.
- valve train damper functions to prevent or reduce valve bounce of valve 13 immediately after the normal valve closing.
- Chamber 39 is then placed under compression, check valve 42 closes and oil is forced from the chamber through the passage 46 and/or between piston 38 and bore 36 in a restricted and controlled fashion.
- This controlled collapse of chamber 39 introduces a damping action into the valve train movement and reduces the closing velocity and impact of the valve 13.
- the check valve 42 opens and the damper mechanism 32 has no further damping effect on the valve train elements.
- Spring 41 causes the piston 38 to extend against ring 42 and to draw oil from the internal passage 37 past the check valve 42 into the chamber 39. The piston is then positioned and ready for its next damping function.
- FIG. 2 An alternate embodiment of the invention is shown in FIG. 2. Only those details difierent from FIG. 1 will be described.
- a damper assembly is referred to generally by number 56 and is formed in part by the cylinder head 11.
- Rocker arm 57 extends past the normal push rod socket 58 to form a portion 59 engagable with an element of the damper assembly 56.
- the damper assembly 56 comprises a blind bore 61 formed within the cylinder head 11 having an axis substantially parallel to that of push rod 31.
- a generally hollow piston 62 is slidably and sealingly received within bore 61 and forms in cooperation with the bore, a variable volume chamber 64.
- Compression spring 66 biases the piston 62 toward its maximum extended position in which it abuts retaining ring 67.
- a one-way valve or check valve assembly 68 permits the flow of oil from internal lubrication passage'69 through port or passage 71 into chamber 64 when the chamber is not under compression.
- the valve assembly includes a perforated cage 72 which retains a ball 73 adjacent port 71. Upon initial compression of the chamber, the ball seats in the port to close check valve 68. Further compression forces oil in a relatively restricted flow through passage 74. A small amount of oil may also force between the piston 62 and bore 61 during chamber compression.
- Piston 62 includes a protruding end 76 adjacent the rocker arm portion 59 which is spaced from the rocker arm at all times except just prior to and just after closure of valve 13.
- FIGS. 1 and 2 are substantially identical.
- Portion 59 of rocker arm 57 engages end 76 of piston 62 near the end of the closing stroke of valve 13.
- Chamber 64 is then compressed causing ball 73 of valve 68 to close port 71.
- Oil from chamber 64 is forced through restricted passage 74 permitting further collapse of the chamber and introducing a damping effect to the valve train movement. Such damping reduces the closing velocity of valve 13 to eliminate or reduce valve bounce.
- valve train comprising elements including a poppet valve reciprocably mounted within said cylinderv head to open and close said port,
- rocker arm pivotally mounted to said cylinder head and engaging said valve
- damping means opposing said spring means and engagable with one of said valve train elements to retard valve closing and reduce valve closing velocity
- damping means being disengagable with said one valve train element during the first portion of the valve closing stroke and engagable with said one element during the latter portion of the valve closing stroke.
- said-damping means comprises a hydraulic device having a variable volume chamber
- said damping means comprising a hydraulic device having a variable volume chamber
- check valve means to permit relatively unrestricted flow into said chamber through said second passage.
- damping means being fixed relative to said cylinder head and including a portion having a bore formed therein,
- check valve means to substantially prevent flow from said chamber through said second passage when the volume of said chamber is decreasing.
- damping means being fixed relative to said cylinder head and including a portion having a bore formed therein,
- second means restricting and controlling collapse of said chamber and permitting relatively unrestricted expansion of said chamber from a collapsed condition.
- dampingfmeans engaging said rocker arm during at least the latter portion of the closing stroke of said firstmentioned valve.
- damping means being fixed relative to said cylinder head and including a portion having a bore formed therein,
- check valve means to substantially prevent flow from said chamber through said passage means when the volume of said chamber is decreasing
- said piston having a predetermined clearance with said bore to permit restricted flow from said chamber between said piston and said bore when the volume of said chamber is decreasing.
- valve train comprising elements including a poppet valve reciprocably mounted within said cylinder head to open and close said port,
- rocker arm pivotally mounted to said cylinder head and engaging said valve
- damping means opposing said spring means and engagable with one of said valve train elements to retard valve closing and reduce valve closing velocity
- damping means being disengagable from said one valve train element during the first portion of the valve closing stroke and engagable with said one element during the latter portion of the valve closing stroke.
- a valve train according to claim 8 wherein:
- said damping means comprises a hydraulic device having a variable volume chamber
- said damping means comprising a hydraulic device having a variable volume chamber
- check valve means to permit relatively unrestricted flow into said chamber through said second passage.
- damping means being fixed relative to said cylinder head and including a portion having a bore formed therein,
- check valve means to substantially prevent flow from said chamber through said second passage when the volume of said chamber is decreasing.
- damping means being fixed relative to said cylinder head and including a portion having a bore formed therein,
- second means restricting and controlling collapse of said chamber and permitting relatively unrestricted expansion of said chamber from a collapsed condition.
- damping means engaging said rocker arm during at least the latter portion of the closing stroke of said firstmentioned valve.
- damping means being fixed relative to said cylinder head and including a portion having a bore formed therein,
- said chamber is decreasing, said piston having a predetermined clearance with said bore to permit restricted flow from said chamber between said piston and said bore when the volume of said chamber is decreasing.
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Valve Device For Special Equipments (AREA)
- Valve-Gear Or Valve Arrangements (AREA)
Abstract
A valve train having a damping means acting on one of the valve train elements prior to valve closing to reduce ''''valve toss'''' or ''''bounce'''' characteristically present at exceptionally high engine speeds. The damping means may comprise a hydraulic or pneumatic device having a collapsible chamber from which flow is restricted and which reduces the velocity of the valve train elements just prior to valve closing.
Description
United States Patent Repko et al.
[ 1 July 25,1972
[54] DAMPED VALVE TRAIN SYSTEM [72] Inventors: Louis L. Repko, Detroit; Richard C. Ronzi, Southfield, both of Mich.
[73] Assignee: Ford Motor Company, Dearborn, Mich.
[22] Filed: Dec. 4, 1970 [21] Appl. No.: 95,220
[52] U.S. Cl ..l23/90.47, 123/9049, 123/9066 [51] lnt.Cl ..F0ll 1/16, F011 1/18 [58] Field of Search ..123/90.47, 90.49. 9066 [56] References Cited UNITED STATES PATENTS 3,563,217 2/1971 Bartels ..l23/90.66 2,552,006 5/1951 Gill, Jr. ..123/90.49 X
2,607,330 8/1952 Hartung ..123/90.47 2,669,228 2/1954 Bergmann ..123/90.47 2,672,134 3/l954 Hunt ..l23/90.47 3,024,775 3/1962 Wuest 123/9047 X Primary Examiner-Al Lawrence Smith Attorney-John R. Faulkner and Roger E. Erickson [5 7] ABSTRACT A valve train having a damping means acting on one of the valve train elements prior to valve closing to reduce valve toss" or bounce" characteristically present at exceptionally high engine speeds. The damping means may comprise a hydraulic or pneumatic device having a collapsible chamber from which flow is restricted and which reduces the velocity 0 the valve train elements just prior to valve closing. I
14 Claims, 2 Drawing Figures Patented July 25, 1972 2 Sheets-Sheet 1 PIC-3.1
s &Q% R o 0 2 E KW w m w? w a m ADQE 5 5% DAMPED VALVE TRAIN SYSTEM BACKGROUND OF THE INVENTION A principal factor limiting the increase of internal combustion engine output by extending the range of engine RPMs is a phenomenon called valve bounce" or valve toss", which results when the intake valve closing velocities are of a magnitude great enough to cause undesirable reopenings of the individual valve elements. These reopenings are caused by the dynamics of the valve train at extremely high rotational speeds rather than in response to the engine camshaft.
This invention provides a valve train construction in which valve bounce is substantially eliminated. Further, it provides a valve train construction in which the closing velocities of the valves are reduced in magnitude just prior to closing impact. The invention also provides a valve train construction in which valve and valve spring life are significantly increased. Still further, this invention provides a damped valve train construction which may be incorporated into conventional internal combustion engines and which may be economically produced.
SUMMARY OF THE INVENTION A damped valve constructed in accordance with this invention comprises elements including a valve reciprocably mounted within an engine cylinder head that opens and closes a port formed within the cylinder head, a rocker arm pivotally mounted to the cylinder head and engagable with the valve, and a push rod engagable with the rocker arm to transmit motion thereto, a spring biasing the valve toward a closed position, and damping means opposing the spring and engagable with one of the above valve train elements to retard closing and to reduce the valve closing velocity.
BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a transverse cross sectional view of a cylinder head and valve train illustrating a bolt-on type damper mechanism engagable with the rocker arm.
FIG. 2 is a transverse cross sectional view of a cylinder head and valve train showing an in-head mounted damper mechanism engagable with the rocker arm.
DESCRIPTION OF A PREFERRED EMBODIMENT FIG. 1 of the drawings shows a preferred embodiment of the invention having a cylinder head 11 formed with an intake passage 12 leading from the intake manifold (not shown) to a combustion chamber (not shown). A poppet valve 13 is slidably mounted within a bore 14 formed within the cylinder head. The valve is axially movable to open and close an intake valve port 16. Compressed between the cylinder head at 17 and a retainer 18 is spring 19 which urges the valve toward a closed position. The retainer is secured to the end of the valve stem by a pair of locks 21 that engage a groove 22 in the end of the valve 13.
A rocker arm 23 is connected to the cylinder head 11 by stud 24. The rocker arm has a concave cylindrical surface 27 on a fulcrum seat 28, retained to stud 24 by nut 29. The rocker arm surface 26 and the fulcrum seat surface 27 determine an axis about which the rocker arm pivots. The end of the rocker arm opposite of the valve engages a push rod 31 which transmits motion from the engine camshaft and a tappet (both not shown) to the rocker arm. The description to this point describes a generally conventional internal combustion engine construction.
A damper or dashpot mechanism 32 is secured to the cylinder head 11 by capscrew 33. The damper 32 includes an arm 34 positioned adjacent the rocker arm 23 and having a blind bore 36 coaxial with the valve 13. A passage 37 is drilled in the arm which communicates with the pressurized lubrication circuit of the engine and provides oil to the bore 36. A generally hollow piston 38 is slidably and sealingly received within bore 36 and forms, in cooperation with the bore, a variable volume chamber 39. Compression spring 41 biases the piston 38 toward its maximum extended position in which it abuts retaining ring 42.
A one-way check valve assembly 42 permits the flow of oil from the internal lubrication passage 37 through port or passage 43 into chamber 39 when the chamber is not under compression. The valve assembly includes a perforated cage 45 which retains a ball 44 adjacent port 43. Upon initial compression of the chamber, ball 44 seats in port 43 to close valve 42. Further compression forces oil in a relatively restricted flow through a vent passage 46. A small clearance may be provided between piston 38 and bore 36 permitting a restricted flow of oil to be forced between the piston and bore during chamber compression. Piston 38 includes a protruding end 47 adjacent the rocker arm 23 which is spaced from the rocker arm at all times except for a short time prior to and after closure of valve 13.
The valve train damper described above functions to prevent or reduce valve bounce of valve 13 immediately after the normal valve closing. Toward the end of the valve closing stroke, portion 48 of the rocker arm'engages the end 47 of piston 38. Chamber 39 is then placed under compression, check valve 42 closes and oil is forced from the chamber through the passage 46 and/or between piston 38 and bore 36 in a restricted and controlled fashion. This controlled collapse of chamber 39 introduces a damping action into the valve train movement and reduces the closing velocity and impact of the valve 13. As the valve 13 begins to open, the check valve 42 opens and the damper mechanism 32 has no further damping effect on the valve train elements. Spring 41 causes the piston 38 to extend against ring 42 and to draw oil from the internal passage 37 past the check valve 42 into the chamber 39. The piston is then positioned and ready for its next damping function.
An alternate embodiment of the invention is shown in FIG. 2. Only those details difierent from FIG. 1 will be described. A damper assembly is referred to generally by number 56 and is formed in part by the cylinder head 11. Rocker arm 57 extends past the normal push rod socket 58 to form a portion 59 engagable with an element of the damper assembly 56.
The damper assembly 56 comprises a blind bore 61 formed within the cylinder head 11 having an axis substantially parallel to that of push rod 31. A generally hollow piston 62 is slidably and sealingly received within bore 61 and forms in cooperation with the bore, a variable volume chamber 64. Compression spring 66 biases the piston 62 toward its maximum extended position in which it abuts retaining ring 67.
A one-way valve or check valve assembly 68 permits the flow of oil from internal lubrication passage'69 through port or passage 71 into chamber 64 when the chamber is not under compression. The valve assembly includes a perforated cage 72 which retains a ball 73 adjacent port 71. Upon initial compression of the chamber, the ball seats in the port to close check valve 68. Further compression forces oil in a relatively restricted flow through passage 74. A small amount of oil may also force between the piston 62 and bore 61 during chamber compression. Piston 62 includes a protruding end 76 adjacent the rocker arm portion 59 which is spaced from the rocker arm at all times except just prior to and just after closure of valve 13.
In function the embodiments of FIGS. 1 and 2 are substantially identical. Portion 59 of rocker arm 57 engages end 76 of piston 62 near the end of the closing stroke of valve 13. Chamber 64 is then compressed causing ball 73 of valve 68 to close port 71. Oil from chamber 64 is forced through restricted passage 74 permitting further collapse of the chamber and introducing a damping effect to the valve train movement. Such damping reduces the closing velocity of valve 13 to eliminate or reduce valve bounce.
We claim:
1. In an internal combustion engine including a cylinder head and a port formed within said cylinder head,
a valve train comprising elements including a poppet valve reciprocably mounted within said cylinderv head to open and close said port,
a rocker arm pivotally mounted to said cylinder head and engaging said valve, and
a push rod engagable with said rocker arm to transmit motion thereto,
spring means biasing said valve toward a closed position,
damping means opposing said spring means and engagable with one of said valve train elements to retard valve closing and reduce valve closing velocity,
said damping means being disengagable with said one valve train element during the first portion of the valve closing stroke and engagable with said one element during the latter portion of the valve closing stroke.
2. A valve train according to claim 1 wherein:
said-damping means comprises a hydraulic device having a variable volume chamber,
means to restrict collapse of said chamber during the valve closing stroke and to permit relatively unrestricted expansion of said chamber during the valve opening stroke.
3. A valve train according to claim 1 and including:
said damping means comprising a hydraulic device having a variable volume chamber,
first passage means leading from said chamber permitting restricted flow during chamber collapse,
second passage means opening into said chamber,
check valve means to permit relatively unrestricted flow into said chamber through said second passage.-
4. A valve train according to claim 1 and including:
said damping means being fixed relative to said cylinder head and including a portion having a bore formed therein,
a piston slidably and sealingly received within said bore,
said piston and said bore forming a variable volume chamber,
means biasing said piston in a direction tending to maximize the volume of said chamber,
a first passage leading from said chamber to permit a restricted flow of hydraulic fluid from said chamber,
a second passage leading to said chamber to permit a relatively unrestricted flow of hydraulic fluid into said chamber,
check valve means to substantially prevent flow from said chamber through said second passage when the volume of said chamber is decreasing.
5. A valve train according to claim 1 and including:
said damping means being fixed relative to said cylinder head and including a portion having a bore formed therein,
a piston slidably and sealingly received within said bore,
said piston and said bore forming a variable volume hydraulic chamber,
first means biasing said piston in a direction tending to maximize the volume of said chamber,
second means restricting and controlling collapse of said chamber and permitting relatively unrestricted expansion of said chamber from a collapsed condition.
6. A valve train according to claim 1 and including:
said dampingfmeans engaging said rocker arm during at least the latter portion of the closing stroke of said firstmentioned valve.
7. A valve train according to claim 1 and including:
said damping means being fixed relative to said cylinder head and including a portion having a bore formed therein,
a piston slidably received within said bore,
said piston and bore forming a variable volume chamber,
means biasing said piston in a direction tending to maximize the volume of said chamber,
passage means leading to said chamber to permit a flow of hydraulic fluid intosaid chamber,
check valve means to substantially prevent flow from said chamber through said passage means when the volume of said chamber is decreasing,
said piston having a predetermined clearance with said bore to permit restricted flow from said chamber between said piston and said bore when the volume of said chamber is decreasing.
8. In an internal combustion engine including a cylinder head and a port formed within said cylinder head,
a valve train comprising elements including a poppet valve reciprocably mounted within said cylinder head to open and close said port,
a rocker arm pivotally mounted to said cylinder head and engaging said valve, and
means engagable with said rocker arm to impart motion thereto,
spring means biasing said valve toward a closed position,
damping means opposing said spring means and engagable with one of said valve train elements to retard valve closing and reduce valve closing velocity,
said damping means being disengagable from said one valve train element during the first portion of the valve closing stroke and engagable with said one element during the latter portion of the valve closing stroke.
9. A valve train according to claim 8 wherein:
said damping means comprises a hydraulic device having a variable volume chamber,
means to restrict collapse of said chamber during the valve closing stroke and to permit relatively unrestricted expansion of said chamber during the valve opening stroke.
10. A valve train according to claim 8 and including:
said damping means comprising a hydraulic device having a variable volume chamber,
first passage means leading from said chamber permitting restricted flow during chamber collapse,
second passage means opening into said chamber,
check valve means to permit relatively unrestricted flow into said chamber through said second passage.
11. A valve train according to claim 8 and including:
said damping means being fixed relative to said cylinder head and including a portion having a bore formed therein,
a piston slidably and sealingly received within said bore,
said piston and said bore forming a variable volume chamber,
means biasing said piston in a direction tending to maximize the volume of said chamber,
a first passage leading from said chamber to permit a restricted flow of hydraulic fluid from said chamber,
a second passage leading to said chamber to permit a relatively unrestricted flow of hydraulic fluid into said chamber,
check valve means to substantially prevent flow from said chamber through said second passage when the volume of said chamber is decreasing.
12. A valve train according to claim 8 and including:
said damping means being fixed relative to said cylinder head and including a portion having a bore formed therein,
a piston slidably and sealingly received within said bore,
said piston and said bore forming a variable volumehydraulic chamber,
first means biasing said piston in a direction tending to maximize the volume of said chamber,
second means restricting and controlling collapse of said chamber and permitting relatively unrestricted expansion of said chamber from a collapsed condition.
13. A valve train according to claim 12 and including:
said damping means engaging said rocker arm during at least the latter portion of the closing stroke of said firstmentioned valve.
14. A valve train according to claim 8 and including:
said damping means being fixed relative to said cylinder head and including a portion having a bore formed therein,
a piston slidably received within said bore,
said piston and bore forming a variable volume chamber,
said chamber is decreasing, said piston having a predetermined clearance with said bore to permit restricted flow from said chamber between said piston and said bore when the volume of said chamber is decreasing.
Claims (14)
1. In an internal combustion engine including a cylinder head and a port formed within said cylinder head, a valve train comprising elements including a poppet valve reciprocably mounted within said cylinder head to open and close said port, a rocker arm pivotally mounted to said cylinder head and engaging said valve, and a push rod engagable with said rocker arm to transmit motion thereto, spring means biasing said valve toward a closed position, damping means opposing said spring means and engagable with one of said valve train elements to retard valve closing and reduce valve closing velocity, said damping means being disengagable with said one valve train element during the first portion of the valve closing stroke and engagable with said one element during the latter portion of the valve closing stroke.
2. A valve train according to claim 1 wherein: said damping means comprises a hydraulic device having a variable volume chamber, means to restrict collapse of said chamber during the valve closing stroke and to permit relatively unrestricted expansion of said chamber during the valve opening stroke.
3. A valve train according to claim 1 and including: said damping means comprising a hydraulic device having a variable volume chamber, first passage means leading from said chamber permitting restricted flow during chamber collapse, second passage means opening into said chamber, check valve means to permit relatively unrestricted flow into said chamber through said second passage.
4. A valve train according to claim 1 and including: said damping means being fixed relative to said cylinder head and including a portion having a bore formed therein, a piston slidably and sealingly received within said bore, said piston and said bore forming a variable volume chamber, means biasing said piston in a direction tending to maximize the volume of said chamber, a first passage leading from said chamber to permit a restricted flow of hydraulic fluid from said chamber, a second passage leading to said chamber to permit a relatively unrestricted flow of hydraulic fluid into said chamber, check valve means to substantially prevent flow from said chamber through said second passage when the volume of said chamber is decreasing.
5. A valve train according to claim 1 and including: said damping means being fixed relative to said cylinder head and including a portion having a bore formed therein, a piston slidably and sealingly received within said bore, said piston and said bore forming a variable volume hydraulic chamber, first means biasing said piston in a direction tending to maximize the volume of said chamber, second means restricting and controlling collapse of said chamber and permitting relatively unrestricted expansion of said chamber from a collapsed condition.
6. A valve train according to claim 1 and including: said damping means engaging said rocker arm during at least the latter portion of the closing stroke of said first-mentioned valve.
7. A valve train according to claim 1 and including: said damping means being fiXed relative to said cylinder head and including a portion having a bore formed therein, a piston slidably received within said bore, said piston and bore forming a variable volume chamber, means biasing said piston in a direction tending to maximize the volume of said chamber, passage means leading to said chamber to permit a flow of hydraulic fluid into said chamber, check valve means to substantially prevent flow from said chamber through said passage means when the volume of said chamber is decreasing, said piston having a predetermined clearance with said bore to permit restricted flow from said chamber between said piston and said bore when the volume of said chamber is decreasing.
8. In an internal combustion engine including a cylinder head and a port formed within said cylinder head, a valve train comprising elements including a poppet valve reciprocably mounted within said cylinder head to open and close said port, a rocker arm pivotally mounted to said cylinder head and engaging said valve, and means engagable with said rocker arm to impart motion thereto, spring means biasing said valve toward a closed position, damping means opposing said spring means and engagable with one of said valve train elements to retard valve closing and reduce valve closing velocity, said damping means being disengagable from said one valve train element during the first portion of the valve closing stroke and engagable with said one element during the latter portion of the valve closing stroke.
9. A valve train according to claim 8 wherein: said damping means comprises a hydraulic device having a variable volume chamber, means to restrict collapse of said chamber during the valve closing stroke and to permit relatively unrestricted expansion of said chamber during the valve opening stroke.
10. A valve train according to claim 8 and including: said damping means comprising a hydraulic device having a variable volume chamber, first passage means leading from said chamber permitting restricted flow during chamber collapse, second passage means opening into said chamber, check valve means to permit relatively unrestricted flow into said chamber through said second passage.
11. A valve train according to claim 8 and including: said damping means being fixed relative to said cylinder head and including a portion having a bore formed therein, a piston slidably and sealingly received within said bore, said piston and said bore forming a variable volume chamber, means biasing said piston in a direction tending to maximize the volume of said chamber, a first passage leading from said chamber to permit a restricted flow of hydraulic fluid from said chamber, a second passage leading to said chamber to permit a relatively unrestricted flow of hydraulic fluid into said chamber, check valve means to substantially prevent flow from said chamber through said second passage when the volume of said chamber is decreasing.
12. A valve train according to claim 8 and including: said damping means being fixed relative to said cylinder head and including a portion having a bore formed therein, a piston slidably and sealingly received within said bore, said piston and said bore forming a variable volume hydraulic chamber, first means biasing said piston in a direction tending to maximize the volume of said chamber, second means restricting and controlling collapse of said chamber and permitting relatively unrestricted expansion of said chamber from a collapsed condition.
13. A valve train according to claim 12 and including: said damping means engaging said rocker arm during at least the latter portion of the closing stroke of said first-mentioned valve.
14. A valve train according to claim 8 and including: said damping means being fixed relative to said cylinder head and including a portion having a bore formed therein, a piston slidably received within said bore, said piston and bore forming a variable volume chamber, means biasing said piston in a direction tending to maximize the volume of said chamber, passage means leading to said chamber to permit a flow of hydraulic fluid into said chamber, check valve means to substantially prevent flow from said chamber through said passage means when the volume of said chamber is decreasing, said piston having a predetermined clearance with said bore to permit restricted flow from said chamber between said piston and said bore when the volume of said chamber is decreasing.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US9522070A | 1970-12-04 | 1970-12-04 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| US3678906A true US3678906A (en) | 1972-07-25 |
Family
ID=22250734
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US95220A Expired - Lifetime US3678906A (en) | 1970-12-04 | 1970-12-04 | Damped valve train system |
Country Status (4)
| Country | Link |
|---|---|
| US (1) | US3678906A (en) |
| CA (1) | CA957226A (en) |
| DE (1) | DE2157222A1 (en) |
| GB (1) | GB1332719A (en) |
Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0016751A2 (en) * | 1980-01-04 | 1980-09-03 | Ford-Werke Aktiengesellschaft | A multi cylinder internal combustion engine |
| US4392461A (en) * | 1980-11-10 | 1983-07-12 | Richard Rotondo | Rocker arm adapter for altering cam profile of exhaust valve |
| US4491098A (en) * | 1980-11-10 | 1985-01-01 | Rotondo Richard D | Device for altering cam profile |
| EP0504709A1 (en) * | 1991-03-13 | 1992-09-23 | Dieter Voigt | Poppet valve drive |
| US5749340A (en) * | 1996-06-11 | 1998-05-12 | Ricardo Consulting Engineers Limited | Hydraulic tappets |
| WO2003067036A1 (en) | 2002-02-04 | 2003-08-14 | Caterpillar Inc. | Engine valve actuator |
| EP2295737A3 (en) * | 2009-08-13 | 2011-06-29 | International Engine Intellectual Property Company, LLC | Intake valve closing hydraulic adjuster |
| WO2014106681A1 (en) * | 2013-01-03 | 2014-07-10 | Wärtsilä Finland Oy | Exhaust valve arrangement and method for controlling closing of an exhaust valve |
| EP3051080A1 (en) * | 2015-02-02 | 2016-08-03 | Caterpillar Energy Solutions GmbH | Variable valve timing systems for internal combustion engines |
| WO2024152263A1 (en) * | 2023-01-18 | 2024-07-25 | Cummins Inc. | Cylinder decompression system, engine, and method of operating |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS606566Y2 (en) * | 1979-07-03 | 1985-03-02 | 日産自動車株式会社 | valve shock absorber |
| DE10237560B4 (en) * | 2002-08-16 | 2007-11-08 | Man Nutzfahrzeuge Ag | Backlash-free valve train for an internal combustion engine |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2552006A (en) * | 1948-10-26 | 1951-05-08 | Jr Thomas J Gill | Internal-combustion engine |
| US2607330A (en) * | 1949-12-07 | 1952-08-19 | Richard S Hartung | Mechanical valve silencer |
| US2669228A (en) * | 1951-05-10 | 1954-02-16 | Johnson Products Inc | Adjusting screw assembly for rocker arms |
| US2672134A (en) * | 1952-09-16 | 1954-03-16 | Jack W Hunt | Valve tappet silencer |
| US3024775A (en) * | 1960-04-29 | 1962-03-13 | Wuest Clemens | Valve tappet |
| US3563217A (en) * | 1968-02-13 | 1971-02-16 | Willy Bartels | Valve attenuator for internal combustion piston engines |
-
1970
- 1970-12-04 US US95220A patent/US3678906A/en not_active Expired - Lifetime
-
1971
- 1971-10-05 GB GB4622471A patent/GB1332719A/en not_active Expired
- 1971-10-14 CA CA125,106A patent/CA957226A/en not_active Expired
- 1971-11-18 DE DE19712157222 patent/DE2157222A1/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2552006A (en) * | 1948-10-26 | 1951-05-08 | Jr Thomas J Gill | Internal-combustion engine |
| US2607330A (en) * | 1949-12-07 | 1952-08-19 | Richard S Hartung | Mechanical valve silencer |
| US2669228A (en) * | 1951-05-10 | 1954-02-16 | Johnson Products Inc | Adjusting screw assembly for rocker arms |
| US2672134A (en) * | 1952-09-16 | 1954-03-16 | Jack W Hunt | Valve tappet silencer |
| US3024775A (en) * | 1960-04-29 | 1962-03-13 | Wuest Clemens | Valve tappet |
| US3563217A (en) * | 1968-02-13 | 1971-02-16 | Willy Bartels | Valve attenuator for internal combustion piston engines |
Cited By (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0016751A2 (en) * | 1980-01-04 | 1980-09-03 | Ford-Werke Aktiengesellschaft | A multi cylinder internal combustion engine |
| EP0016751B1 (en) * | 1980-01-04 | 1983-02-16 | Ford-Werke Aktiengesellschaft | A multi cylinder internal combustion engine |
| US4392461A (en) * | 1980-11-10 | 1983-07-12 | Richard Rotondo | Rocker arm adapter for altering cam profile of exhaust valve |
| US4491098A (en) * | 1980-11-10 | 1985-01-01 | Rotondo Richard D | Device for altering cam profile |
| EP0504709A1 (en) * | 1991-03-13 | 1992-09-23 | Dieter Voigt | Poppet valve drive |
| US5749340A (en) * | 1996-06-11 | 1998-05-12 | Ricardo Consulting Engineers Limited | Hydraulic tappets |
| WO2003067036A1 (en) | 2002-02-04 | 2003-08-14 | Caterpillar Inc. | Engine valve actuator |
| EP2295737A3 (en) * | 2009-08-13 | 2011-06-29 | International Engine Intellectual Property Company, LLC | Intake valve closing hydraulic adjuster |
| US8069828B2 (en) | 2009-08-13 | 2011-12-06 | International Engine Intellectual Property Company, Llc | Intake valve closing hydraulic adjuster |
| WO2014106681A1 (en) * | 2013-01-03 | 2014-07-10 | Wärtsilä Finland Oy | Exhaust valve arrangement and method for controlling closing of an exhaust valve |
| EP3051080A1 (en) * | 2015-02-02 | 2016-08-03 | Caterpillar Energy Solutions GmbH | Variable valve timing systems for internal combustion engines |
| WO2024152263A1 (en) * | 2023-01-18 | 2024-07-25 | Cummins Inc. | Cylinder decompression system, engine, and method of operating |
Also Published As
| Publication number | Publication date |
|---|---|
| DE2157222A1 (en) | 1972-06-15 |
| CA957226A (en) | 1974-11-05 |
| GB1332719A (en) | 1973-10-03 |
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