Vehicle leveling system

Claim 2

In a leveling system for controlling the attitude between first and second portions of a vehicle, shock absorber means adapted for attachment to one of the vehicle portions, first housing means defining a fluid chamber and adapted for attachment to the other of the vehicle portions, means for communicating actuating fluid to said chamber, whereby expansion and contraction of said chamber will effect preselected changes in attitude between said first and second vehicle portions, second housing means containing a preselected volume of pressurized gas, a generally cylindrically shaped flexible partition arranged generally coaxially of said shock absorber and having one side thereof communicable with said fluid chamber and the opposite side thereof communicable with said volume of gas, whereby contraction of said fluid chamber will result in fluid being transmitted out of said chamber and thereby bias said partition means toward said second housing means against the resistance of the pressurized gas therewithin, one of said housing means being disposed in generally surrounding relation with respect to the other of said housing means.

Claim 3

A vehicle leveling system as set forth in claim 1 which includes flexible diaphragm means extending between said first housing means and said shock absorber means and which defines a portion of said fluid chamber.

Claim 4

A leveling system as set forth in claim 1 which includes valve means for selectively communicating actuating fluid to and from said fluid chamber.

Claim 5

A leveling system as set forth in claim 3 wherein said valve means is actuable in response to relative movement between said first housing means and said shock absorber means.

Claim 6

A leveling system as set forth in claim 3 wherein said valve means comprises a valve housing defining a valve bore, a valve member reciprocable within said bore, inlet and outlet passage means for communicating actuating fluid to and from said bore, and means for moving said valve member into alignment with said passage means in response to relative movement between said first housing means and said shock absorber means.

Claim 7

A leveling system as set forth in claim 5 which includes spring means disposed within said fluid chamber and connected to said valve member for biasing said member within the said bore in response to relative movement between said first housing means and said shock absorber means.

Claim 8

A leveling system as set forth in claim 5 which includes damping means for limiting movement of said valve member within said bore.

Claim 9

In a leveling system for controlling the attitude between the sprung and unsprung portions of a vehicle, a pair of suspension assemblies each including a suspension unit and an associated spring unit, said suspension units each comprising a hydraulic direct-acting shoCk absorber and a first housing means defining a fluid chamber, means for securing a first portion of each of said units to the unsprung portion of the vehicle and a second portion of said units to the sprung portion of the vehicle, said spring units each comprising a second housing means and a generally cylindrically shaped flexible partition means dividing the interior thereof into first and second compartments, said second housing means generally surrounding said housing means of the associated of said suspension units, said first compartments of said spring units being charged with a preselected volume of pressurized gas, said second compartments of said spring units being communicable with the fluid chamber of the associated suspension unit and each of said second compartments and said fluid chambers being communicable with a source of actuating fluid, with said fluid acting against one side of said partition means and said pressurized gas acting against the opposite side of said partition means, whereby contraction of said fluid chambers upon relative movement of said first and second portions thereof will result in fluid being transmitted to said second compartments of said spring units to bias said partition means toward said first compartments against the resistance of the pressurized gas within said first compartments.

Claim 10

In a leveling system for controlling the attitude between the sprung and unsprung portions of a vehicle, a pair of suspension assemblies each including a suspension unit and an associated spring unit, said suspension units each comprising a hydraulic direct-acting shoCk absorber and a first housing means defining a fluid chamber, means for securing a first portion of each of said units to the unsprung portion of the vehicle and a second portion of said units to the sprung portion of the vehicle, said spring units each comprising a second housing means and a generally cylindrically shaped flexible partition means dividing the interior thereof into first and second compartments, said second housing means generally surrounding said housing means of the associated of said suspension units, said first compartments of said spring units being charged with a preselected volume of pressurized gas, said second compartments of said spring units being communicable with the fluid chamber of the associated suspension unit and each of said second compartments and said fluid chambers being communicable with a source of actuating fluid, with said fluid acting against one side of said partition means and said pressurized gas acting against the opposite side of said partition means, whereby contraction of said fluid chambers upon relative movement of said first and second portions thereof will result in fluid being transmitted to said second compartments of said spring units to bias said partition means toward said first compartments against the resistance of the pressurized gas within said first compartments.

Claim 11

A leveling system as set forth in claim 8 which includes fluid conduit means communicating said fluid chambers of each of said suspension units, whereby contraction of one of said fluid chambers results in actuating fluid being transmitted to the fluid chamber of the other of said suspension units.

Claim 12

A leveling system as set forth in claim 9 wherein said suspension assemblies are mounted at the front and rear end of the vehicle along the same side thereof to reduce pitching movement of the sprung portion of the vehicle.

Claim 13

A leveling system as set forth in claim 9 wherein said suspension assemblies are mounted at one end of the vehicle adjacent the opposite sides thereof, whereby to reduce rolling movement of the sprung portion of the vehicle.

Claim 14

A leveling system as set forth in claim 9 which includes fluid conduit means communicating said second compartments of said spring units, whereby contraction of one of said fluid chambers results in actuating fluid being transmitted to said second compartment of the spring units of each of said suspension assemblies, whereby to reduce the spring rate of said assemblies.

Claim 15

A leveling system as set forth in claim 9 which includes load compensator means communicable with the fluid chamber of each of said suspension units, said load compensator means comprising first and second fluid compartments and means for forcing fluid from one of said compartments in response to an increase in fluid pressure in the other of said compartments.

Claim 16

A leveling system as set forth in claim 8 which includes valve means for selectively communicating actuating fluid to and from said fluid chamber of each of said suspension units.

Claim 17

A leveling system as set forth in claim 14 wherein said valve means is actuable in response to relative movement between said vehicle sections, and which includes a source of pressurized actuating fluid and means for communicating said source with said valve means.

Claim 18

A leveling system as set forth in claim 15 wherein said source of pressurized actuating fluid comprises a fluid reservoir and pump means for pumping actuating fluid between said reservoir and said suspension assemblies.

Claim 19

A leveling system as set forth in claim 8 which includes first and second pairs of suspension assemblies each comprising one of said spring units, said first and second pair of suspension assemblies being disposed at the front and rear ends of the vehicle along the opposite sides thereof, and which includes conduit means communicating in suspension assemblies along the same sides of the vehicle, whereby to reduce pitching movement of the sprung portion of the vehicle.

Claim 20

In a suspension unit for a vehicle having sprung and unsprung portions, first housing means defining a variable volume fluid chamber, leveling means for varying the attitude between said vehicle portions in response to changes in the volume of said fluid chamber, second housing means defining a pressurized gas chamber, one of said housing means being disposed in substantial surrounding relation with respect to the other of said housing means, and flexible partition means having fluid communicable with said fluid chamber acting against one side thereof and pressurized gas communicable with said gas chamber acting against the opposite side thereof.

Claim 21

In a suspension unit for a vehicle having sprung and unsprung portions, first housing means defining a variable volume fluid chamber, leveling means for varying the attitude between said vehicle portions in response to changes in the volume of said fluid chamber, second housing means defining a pressurized gas chamber, one of said housing means being disposed in substantial surrounding relation with respect to the other of said housing means, and flexible partition means having fluid communicable with said fluid chamber acting against one side thereof and pressurized gas communicable with said gas chamber acting against the opposite side thereof.

Claim 22

In a suspension system, a suspension unit comprising a generally cylindrically shaped outer housing member, first and second attachment means spaced axially of said housing member and adapted to be secured to two relatively movable members, a generally cylindrically shaped flexible partition member extending axially within said housing member and separating the interior thereof into first and second radially adjacent chambers, said first chamber being charged with a preselected quantity of pressurized gas and said second chamber having a volume of actuating fluid therein, and means including a source of actuating fluid communicable with said second chamber and adapted to act against one side of said partition member for varying the axial spacing between said attachment means in response to changes in volume of said actuating fluid in said second chamber.

Claim 23

In a suspension system, a suspension unit comprising a generally cylindrically shaped outer housing member, first and second attachment means spaced axially of said housing member and adapted to be secured to two relatively movable members, a generally cylindrically shaped flexible partition member extending axially within said housing member and separating the interior thereof into first and second radially adjacent chambers, said first chamber being charged with a preselected quantity of pressurized gas and said second chamber having a volume of actuating fluid therein, and means including a source of actuating fluid communicable with said second chamber and adapted to act against one side of said partition member for varying the axial spacing between said attachment means in response to changes in volume of said actuating fluid in said second chamber.

Claim 24

A suspension system as set forth in claim 19 wherein said first chamber extends at least partly around said second chamber, and wherein expansion of said second chamber is resisted by said pressurized gas in said first chamber.

Claim 25

In a vehicle leveling apparatus, a direct-acting hydraulic shock absorber, a generally cylindrical housing arranged concentrically of said shock absorber, first attachment means for securing one end of said shock absorber to one portion of a vehicle and second attachment means for securing one end of said housing to another portion of the vehicle, a flexible diaphragm member extending between said shock absorber and said housing and defining therewith a first fluid chamber, an air spring unit disposed in generally surrounding relationship with respect to said housing, said unit comprising a second fluid chamber and a gas chamber separated by a flexible partition, said first and second fluid chambers being communicable with one another, whereby contraction of said first fluid chamber will result in fluid being transmitted out of said first fluid chamber to said second fluid chamber and bias said partition means toward said gas chamber against the resistance of the pressurized gas therewithin.

Claim 26

In a vehicle leveling apparatus, a direct-acting hydraulic shock absorber, a generally cylindrical housing arranged concentrically of said shock absorber, first attachment means for securing one end of said shock absorber to one portion of a vehicle and second attachment means for securing one end of said housing to another portion of the vehicle, a flexible diaphragm member extending between said shock absorber and said housing and defining therewith a first fluid chamber, an air spring unit disposed in generally surrounding relationship with respect to said housing, said unit comprising a second fluid chamber and a gas chamber separated by a flexible partition, said first and second fluid chambers being communicable with one another, whereby contraction of said first fluid chamber will result in fluid being transmitted out of said first fluid chamber to said second fluid chamber and bias said partition means toward said gas chamber against the resistance of the pressurized gas therewithin.