Hydro-pneumatic spring system, especially for motor vehicles

Claim 2

A hydropneumatic spring system having automatic level control both for regulation of loads during standstill and relief thereof controlled during running operation, especially for motor vehicles with two separate preloaded gaseous cushions operable to act upon a hydraulic medium which is controlled according to load by a pump and control mechanism, which comprises: a cylinder, a hollow piston rod reciprocably arranged in said cylinder, a high pressure fluid storage container, operating chamber means associated with said cylinder, a hollow pump rod having an axial bore and being axially movable in said hollow piston rod, a pump piston carried by a free end of said hollow pump rod, a valve body slidably guided with respect to said hollow pump rod and having an abutment operable in upward leveling position to rest against said pump piston, said valve body including valve seat means, an insert member having a seat surface adapted to be engaged and disengaged by said valve seat means, and throttle means associated with said valve body and operable in response to said valve seat means disengaging said seat surface to establish fluid communication between said high-pressure fluid storage container and said operating chamber.

Claim 3

A hydropneumatic spring system according to claim 1, which includes a check valve arranged in said pump piston, and in which in upward leveling position said abutment is operable to cover said check valve so as to rearwardly seal and close the same.

Claim 4

A hydropneumatic spring system having automatic level control for regulation of loads during standstill and relief thereof during running operation, especially for motor vehicles with two separate preloaded gaseous cushions operable to act upon a hydraulic medium which is controlled according to load by a pump and control mechanism, which comprises: a cylinder, a hollow piston rod reciprocably arranged in said cylinder, a high-pressure fluid storage container, operating chamber means associated with said cylinder, a hollow pump rod having an axial bore and being axially movable in said hollow piston rod, a pump piston carried by a free end of said hollow pump rod, a valve body slidably guided with respect to said hollow pump rod and having an abutment operable in upward leveling position to rest against said pump piston, said valve body including valve seat means, an insert member having a seat surface adapted to be engaged and disengaged by said valve seat means, throttle means associated with said valve body and operable in response to said valve seat means disengaging said seat surface to establish fluid communication between said high-pressure fluid storage container and said operating chamber, said pump piston being provided with radial passage means and with an annular passage communicating with said radial passage means, and said valve body having longitudinal groove means adapted in the normal range of said valve body to communicate with said annular passage for conveying the pressure prevailing in said high-pressure fluid storage container through said radial passage means and said annular passage to said valve seat means to press the same against said seat surface of said insert member, and preloaded spring means continuously urging said valve seat means against the seat surface of said insert member.

Claim 5

A hydropneumatic spring system having automatic level control for regulation of loads during standstill and relief thereof during running operation, especially for motor vehicles with two separate preloaded gaseous cushions operable to act upon a hydraulic medium which is controlled according to load by a pump and control mechanism, which comprises: a cylinder, a hollow piston rod reciprocably arranged in said cylinder, a high-pressure fluid storage container, operating chamber means associated with said cylinder, a hollow pump rod having an axial bore and being axially movable in said hollow piston rod, a pump piston carried by a free end of said hollow pump rod, a valve body slidably guided with respect to said hollow pump rod and having an abutment operable in upward leveling position to rest against said pump piston, said valve body including valve seat means, an insert member having a seat surface adapted to be engaged and disengaged by said valve seat means, throttle means associated with said valve body and operable in response to said valve seat means disengaging said seat surface to establish fluid communication between said high-pressure fluid storage container and said operating chamber, said pump piston being provided with radial passage means and with an annular passage communicating with said radial passage means, and said valve body having longitudinal groove means adapted in the normal range of said valve body to communicate with said annular passage for conveying the pressure prevailing in said high-pressure fluid storage container through said radial passage means and said annular passage to said valve seat means to press the same against said seat surface of said insert member, and preloaded spring means continuously urging said valve seat means against the seat surface of said insert member.

Claim 6

A hydropneumatic spring system according to claim 3, in which in pumping range said valve body with the valve seat operating as the inlet valve and making possible pump operation with said check valve in said pump piston.

Claim 7

A hydropneumatic spring system according to claim 3, in which a damping piston is so provided inside said spring system that the suction stepwise damping is buffered between rigid walls and the pressure stepwise damping is effected by means of the pressure in the operating chamber.

Claim 8

A hydropneumatic spring system according to claim 3, which includes guiding means for said piston rod and also includes a pressure stepwise limiting valve associated with said guiding means for operatively limiting the pressure stepwise damping.

Claim 9

A hydropneumatic spring system according to claim 3, in which an overpressure valve means is provided in a supporting body.

Claim 10

A hydropneumatic spring system according to claim 3, which includes an upper suspension for said spring system and also includes high-pressure storage means arranged above said upper suspension.

Claim 11

A hydropneumatic spring system according to claim 8, in which a separating element formed at its upper end as a sealing ring is immersed in the slight liquid level of the operating chamber.

Claim 12

A hydropneumatic spring system having automatic level control for regulation of loads during standstill and relief thereof during running operation, especially for motor vehicles with two separate preloaded gaseous cushions operable to act upon a hydraulic medium which is controlled according to load by a pump and control mechanism, which comprises: a cylinder, a hollow piston rod reciprocably arranged in said cylinder, a high-pressure fluid storage container, operating chamber means associated with said cylinder, a hollow pump rod having an axial bore and being axially movable in said hollow piston rod, a pump piston carried by a free end of said hollow pump rod, a valve body slidably guided with respect to said hollow pump rod and having an abutment operable in upward leveling position to rest against said pump piston, said valve body including valve seat means, an insert member having a seat surface adapted to be engaged and disengaged by said valve seat means, throttle means associated with said valve body and operable in response to said valve seat means disengaging said seat surface to establish fluid communication between said high-pressure fluid storage container and said operating chamber, an upper suspension for said spring system and also high-pressure storage means arranged above said upper suspension, and a check valve being provided in said upper suspension.

Claim 13

A hydropneumatic spring system having automatic level control for regulation of loads during standstill and relief thereof during running operation, especially for motor vehicles with two separate preloaded gaseous cushions operable to act upon a hydraulic medium which is controlled according to load by a pump and control mechanism, which comprises: a cylinder, a hollow piston rod reciprocably arranged in said cylinder, a high-pressure fluid storage container, operating chamber means associated with said cylinder, a hollow pump rod having an axial bore and being axially movable in said hollow piston rod, a pump piston carried by a free end of said hollow pump rod, a valve body slidably guided with respect to said hollow pump rod and having an abutment operable in upward leveling position to rest against said pump piston, said valve body including valve seat means, an insert member having a seat surface adapted to be engaged and disengaged by said valve seat means, throttle means associated with said valve body and operable in response to said valve seat means disengaging said seat surface to establish fluid communication between said high-pressure fluid storage container and said operating chamber, an upper suspension for said spring system and also high-pressure storage means arranged above said upper suspension, and a check valve being provided in said upper suspension.

Claim 14

A hydropneumatic spring system according to claim 10, in which a check valve is installed in the high-pressure storage.

Claim 15

A hydropneumatic spring system according to claim 10, in which during installation of the high-pressure storage there is an outward sealing with respect thereto, a check valve being provided in said upper suspension of the spring system and upon further tightened installation there is opening of the high-pressure storage by check valve means.

Claim 16

A hydropneumatic spring system having automatic level control for regulation of loads during standstill and relief thereof during running operation, especially for motor vehicles with two separate preloaded gaseous cushions operable to act upon a hydraulic medium which is controlled according to load by a pump and control mechanism, which comprises: a cylinder, a hollow piston rod reciprocably arranged in said cylinder, a high-pressure fluid storage container, operating chamber means associated with said cylinder, a hollow pump rod having an axial bore and being axially movable in said hollow piston rod, a pump piston carried by a free end of said hollow pump rod, a valve body slidably guided with respect to said hollow pump rod and having an abutment operable in upward leveling position to rest against said pump piston, said valve body including valve seat means, an insert member having a seat surface adapted to be engaged and disengaged by said valve seat means, throttle means associated with said valve body and operable in response to said valve seat means disengaging said seat surface to establish fluid communication between said high pressure fluid storage container and said operating chamber, particularly without hydraulic damping there being provided a hollow connecting rod axially movable internally of said hollow piston rod, a closure member provided in the unpreloaded end of said connecting rod, a valve body portion likewise axially movable to slide upon said closure member and engageable in regulating range to abut upon said closure member, said valve body portion thereby lifting from a valve seat of a surface of a piston and making possible passage of hydraulic medium from the high pressure storage into an operating chamber through a throttle bore in said closure member.

Claim 17

A hydropneumatic spring system having automatic level control for regulation of loads during standstill and relief thereof during running operation, especially for motor vehicles with two separate preloaded gaseous cushions operable to act upon a hydraulic medium which is controlled according to load by a pump and control mechanism, which comprises: a cylinder, a hollow piston rod reciprocably arranged in said cylinder, a high-pressure fluid storage container, operating chamber means associated with said cylinder, a hollow pump rod having an axial bore and being axially movable in said hollow piston rod, a pump piston carried by a free end of said hollow pump rod, a valve body slidably guided with respect to said hollow pump rod and having an abutment operable in upward leveling position to rest against said pump piston, said valve body including valve seat means, an insert member having a seat surface adapted to be engaged and disengaged by said valve seat means, throttle means associated with said valve body and operable in response to said valve seat means disengaging said seat surface to establish fluid communication between said high pressure fluid storage container and said operating chamber, particularly without hydraulic damping there being provided a hollow connecting rod axially movable internally of said hollow piston rod, a closure member provided in the unpreloaded end of said connecting rod, a valve body portion likewise axially movable to slide upon said closure member and engageable in regulating range to abut upon said closure member, said valve body portion thereby lifting from a valve seat of a surface of a piston and making possible passage of hydraulic medium from the high pressure storage into an operating chamber through a throttle bore in said closure member.

Claim 18

A hydropneumatic spring system according to claim 13, in which in the regulation position said abutment uncovers sealing of said bores.

Claim 19

A hydropneumatic spring system according to claim 13, in which a piston ring in a groove in normal range controls upwardly in said operating cylinder and thereby stops pump operation, while the pressure of the high-pressure storage through bores is operative upon a valve seat of a valve body and presses the same upon the surface of said piston and avoids a further upward regulation.

Claim 20

A hydropneumatic spring system according to claim 15, in which in pumping range the piston is located below the groove in said operating cylinder, said check valve serving as a suction vent and said valve body with the pressure seat serving as a pressure vent whereby the pump operation is attained.