Mechanism for adjusting and maintaining the valve play in internal combustion engines, especially in motor vehicle internal combustion engines

Claim 3

A device according to claim 1, characterized in that the first piston means includes a guide cylinder and an annular portion, and in that the guide cylinder includes at the outwardly facing end thereof a ball head for the support of the rocker arm and at the other end thereof the annular portion which in its turn carries a seal means with respect to the housing.

Claim 4

A device according to claim 2, characterized in that the second piston means is constructed pot-shaped and extends with a central piston body thereof through the annular portion of the first piston means, and in that a ring means is provided at the body end of the second piston means, whereby the axial spacing between the ring means and the piston body at the second piston means is larger corresponding to the predetermined valve clearance than the axial width of the annular portion in the first piston means.

Claim 5

A device according to claim 3, wherein said ring means is securely mounted to the end of the piston body.

Claim 6

A device according to claim 3, characterized in that the piston bottom at the second piston means is provided with star-like groove means.

Claim 7

A device according to claim 5, characterized in that the end face of the annular portion at the first piston means facing the second piston means is provided with star-like groove means.

Claim 8

A device according to claim 3, characterized in that the end face of the annular portion at the first piston means facing the second piston means is provided with star-like groove means.

Claim 9

A device according to claim 3, characterized in that at least one of the piston bottom of the second piston means and the end face of the annular portions of the first means facing the second piston means is provided with groove-like means.

Claim 10

A device according to claim 8, characterized in that a predetermined slight clearance exists between the body of the second piston means and its receiving bore in the annular portion of the first piston means.

Claim 11

A device according to claim 9, characterized in that the potshaped portion of the second piston means is drawn-in at the outer end thereof and thus serves as abutment for a conical spring of the check valve means.

Claim 12

A device according to claim 10, characterized in that a compression spring is arranged in the guide cylinder of the first piston means which seeks to displace the second piston means constantly in the direction away from the ball head.

Claim 13

A device according to claim 11, characterized in that an axial bore is arranged in the ball head which corresponds to a corresponding bore in the socket of the abutting rocker arm.

Claim 14

A device according to claim 12, characterized in that at least one inclined bore means is provided underneath the ball head in the bottom of the guide cylinder means, said bore means terminating freely in the outward direction.

Claim 15

A device according to claim 13, characterized in that several inclined bore means are provided.

Claim 18

A device according to claim 15, characterized in that a predetermined slight clearance exists between the body of the second piston means and its receiving bore in the annular portion of the first piston means.

Claim 19

A device according to claim 15, characterized in that the pot-shaped portion of the second piston means is drawn-in at the outer end thereof and thus serves as abutment for a conical spring of the check valve means.

Claim 24

A device according to claim 19, characterized in that the first piston means includes a guide cylinder and an annular portion, and in that the guide cylinder includes at the outwardly facing end thereof a ball head for the support of the rocker arm and at the other end thereof the annular portion which in its turn carries a seal means with respect to the housing.

Claim 25

A device according to claim 20, characterized in that the annular portion is secured to said other end of the guide cylinder.

Claim 26

A device according to claim 20, characterized in that the guide cylinder forms the ball head.

Claim 27

A device according to claim 20, characterized in that the ball head is mounted at said one end of the guide cylinder.

Claim 28

A device according to claim 20, characterized in that a compression spring is arranged in the guide cylinder of the first piston means which seeks to displace the second piston means constantly in the direction away from the ball head.

Claim 33

A device according claim 26, characterized in that an axial bore is arranged in the ball head which corresponds to a corresponding bore in the socket of the abutting rocker arm.

Claim 34

Valve play adjusting apparatus comprising: a housing, a first piston movably disposed in said housing and including rocker arm engaging means for engaging a valve rocker arm or movement therewith, a second piston movably disposed in said housing, a fluid reservoir space and a fluid pressure space communicating directly with respective oppositely facing pressure surfaces of said pistons such that said pistons are moved together in respective opposite direction dependent on forces exerted thereon by the rocker arm and on changes in the relative fluid pressures in said reservoir space and pressure space, said first and second pistons being provided with respective abutment surface portions in facing relationship to one another, and spacing means for maintaining said first and second pistons with said abutment surface portions spaced a predetermined distance from one another when the pressure difference between said reservoir space is below a certain value while permitting said first and second pistons to move toward one another until said abutment surface portions abuttingly engage one another whenever the pressure difference is sufficiently above said certain value, wherein at least one of said abutment surface portions includes groove means for accommodating leakage of fluid between said abutment surface portions when in abutting engagement with one another.

Claim 35

Valve play adjusting apparatus comprising: a housing, a first piston movably disposed in said housing and including rocker arm engaging means for engaging a valve rocker arm or movement therewith, a second piston movably disposed in said housing, a fluid reservoir space and a fluid pressure space communicating directly with respective oppositely facing pressure surfaces of said pistons such that said pistons are moved together in respective opposite direction dependent on forces exerted thereon by the rocker arm and on changes in the relative fluid pressures in said reservoir space and pressure space, said first and second pistons being provided with respective abutment surface portions in facing relationship to one another, and spacing means for maintaining said first and second pistons with said abutment surface portions spaced a predetermined distance from one another when the pressure difference between said reservoir space is below a certain value while permitting said first and second pistons to move toward one another until said abutment surface portions abuttingly engage one another whenever the pressure difference is sufficiently above said certain value, wherein at least one of said abutment surface portions includes groove means for accommodating leakage of fluid between said abutment surface portions when in abutting engagement with one another.

Claim 36

Apparatus according to claim 28, wherein said first piston is slidably guided in said housing and surrounds said reservoir space, wherein said second piston is slidably guided in a part of said first piston located at one axial end of said reservoir space, wherein the end of said second piston facing away from said first piston forms part of the boundary for said pressure space, and wherein the abutment surface of said first piston is at the extreme end thereof which faces the pressure space while the abutment surface of said second piston is formed on an annular shoulder portion which has a larger cross-sectional dimension than does the portion of the second piston guided in said first piston.

Claim 37

Apparatus according to claim 29, wherein said spacing means includes resilient means biasing said pistons away from one another and stop means limiting the maximum amount the pistons can be spaced from one another, said stop means including a ring member attached to said second piston at the end of said second piston which bounds a portion of said reservoir space.

Claim 38

Apparatus according to claim 30, wherein said reservoir space and said pressure space are communicated with one another by a check valve and by leakage openings between the outer walls of the second piston and the inner walls of the first piston adjacent thereto.

Claim 39

Apparatus according to claim 31, wherein a spring is interposed between said housing and said first piston for biasing said pistons in a first direction, and wherein a Z-shaped cross-section ring disk is provided at said first piston which simultaneously serves as a first abutment for said spring and a second abutment engageable with the housing for limiting maximum movement of the first piston in a second direction opposite said first direction.

Claim 40

Apparatus according to claim 29, wherein a spring is interposed between said housing and said first piston for biasing said pistons in a first direction, and wherein a Z-shaped cross-section ring disk is provided at said first piston which simultaneously serves as a first abutment for said spring and a second abutment engageable with the housing for limiting maximum movement of the first piston in a second direction opposite said first direction.

Claim 41

Apparatus according to claim 28, wherein said spacing means includes resilient means biasing said pistons away from one another and stop means limiting the maximum amount the pistons can be spaced from one another.

Claim 42

Apparatus according to claim 28, wherein a spring is interposed between said housing and said first piston for biasing said pistons in a first direction, and wherein a Z-shaped cross-section ring disk is provided at said first piston which simultaneously serves as a first abutment for said spring and a second abutment engageable with the housing for limiting maximum movement of the first piston in a second direction opposite said first direction.

Claim 43

A valve adjusting apparatus comprising: a housing, a first piston movably disposed in said housing and including rocker arm engaging means for engaging a valve rocker arm for movement therewith, a second piston movably disposed in said housing, a fluid reservoir space and a fluid pressure space communicating directly with respective oppositely facing pressure surfaces of said pistons such that said pistons are moved together in respective opposite directions dependent on forces exerted thereon by the rocker arm and on changes in the relative fluid pressures in said reservoir space and pressure space, said first and second pistons being provided with respective abutment surface portions in facing relationship to one another, and spacing means for maintaining said first and second pistons with said abutment surface portions spaced a predetermined distance from one another when the pressure difference between said reservoir space is below a certain value while permitting said first and second pistons to move toward one another until said abutment surface portions abuttingly engage one another when the pressure difference is sufficiently above said certain value, wherein said first piston is slidably guided in said housing and surrounds said reservoir space, wherein said second piston is slidably guided in a part of said first piston located at one axial end of said reservoir space, wherein the end of said second piston facing away from said first piston forms part of the boundary for said pressure space, and wherein the abutment surface of said first piston is at the extreme end thereof which faces the pressure space while the abutment surface of said second piston is formed on an annular shoulder portion which has a larger cross-sectional dimension than does the portion of the second piston guided in said first piston.

Claim 44

A valve adjusting apparatus comprising: a housing, a first piston movably disposed in said housing and including rocker arm engaging means for engaging a valve rocker arm for movement therewith, a second piston movably disposed in said housing, a fluid reservoir space and a fluid pressure space communicating directly with respective oppositely facing pressure surfaces of said pistons such that said pistons are moved together in respective opposite directions dependent on forces exerted thereon by the rocker arm and on changes in the relative fluid pressures in said reservoir space and pressure space, said first and second pistons being provided with respective abutment surface portions in facing relationship to one another, and spacing means for maintaining said first and second pistons with said abutment surface portions spaced a predetermined distance from one another when the pressure difference between said reservoir space is below a certain value while permitting said first and second pistons to move toward one another until said abutment surface portions abuttingly engage one another when the pressure difference is sufficiently above said certain value, wherein said first piston is slidably guided in said housing and surrounds said reservoir space, wherein said second piston is slidably guided in a part of said first piston located at one axial end of said reservoir space, wherein the end of said second piston facing away from said first piston forms part of the boundary for said pressure space, and wherein the abutment surface of said first piston is at the extreme end thereof which faces the pressure space while the abutment surface of said second piston is formed on an annular shoulder portion which has a larger cross-sectional dimension than does the portion of the second piston guided in said first piston.

Claim 45

Apparatus according to claim 36, wherein a spring is interposed between said housing and said first piston for biasing said pistons in a first direction, and wherein a Z-shaped cross-section ring disk is provided at said first piston which simultaneously serves as a first abutment for said spring and a second abutment engageable with the housing for limiting maximum movement of the first piston in a second direction opposite said first direction.

Claim 46

Valve play adjusting apparatus comprising: a housing, a piston movably disposed in said housing and including rocker arm engaging means for engaging a valve rocker arm for movement therewith, and a fluid reservoir space and a fluid pressure space communicating directly with respect to oppositely facing pressure surfaces of said piston such that said piston is moved in respective opposite directions in dependence on the forces exerted thereon by the rocker arM and on changes in the relative fluid pressures in said reservoir space and pressure space, wherein a spring is interposed between said housing and said first piston for biasing said pistons in a first direction, and wherein a Z-shaped cross-section rink disk is provided at said first piston which simultaneously serves as a first abutment for said spring and a second abutment engageable with the housing for limiting maximum movement of the first piston in a second direction opposite and first direction.

Claim 47

Valve play adjusting apparatus comprising: a housing, a piston movably disposed in said housing and including rocker arm engaging means for engaging a valve rocker arm for movement therewith, and a fluid reservoir space and a fluid pressure space communicating directly with respect to oppositely facing pressure surfaces of said piston such that said piston is moved in respective opposite directions in dependence on the forces exerted thereon by the rocker arM and on changes in the relative fluid pressures in said reservoir space and pressure space, wherein a spring is interposed between said housing and said first piston for biasing said pistons in a first direction, and wherein a Z-shaped cross-section rink disk is provided at said first piston which simultaneously serves as a first abutment for said spring and a second abutment engageable with the housing for limiting maximum movement of the first piston in a second direction opposite and first direction.