Vehicular seat mounting linkage
First Claim
1. An operator seat assembly in a vehicle having a longitudinal axis and an operator station, the seat assembly being disposed in the operator station and comprising a base structure secured to the vehicle, a seat frame for supporting an operator, forward and rearward link means respectively pivoted between said base structure and said seat frame, said rearward link means Being effectively longer than said forward link means, said forward and rearward links forming in combination with said seat frame and said base structure to which they are pivotably affixed an unsymmetric quadrilateral having sides of fixed length, said forward and rearward link means being disposed with their respective linear axes tending to remain in substantial convergence adjacent a relatively remote point located below and in longitudinally spaced apart relation forward of the seat assembly, said point of convergence being preselected with reference to the vehicle, and a resilient means effectively interconnected between said seat frame and said base structure for yieldingly resisting movement of said seat frame relative to said base structure.
1 Assignment
0 Petitions
Accused Products
Abstract
A seat assembly for use in a variety of vehicles, particularly to isolate an operator from oscillatory movements on the vehicle, the operator'"'"''"'"'s seat being arranged for movement relative to a remote point located below and in longitudinally spaced apart relation from the seat assembly, preferably by means of forward and rearward links pivotably mounting the seat upon a base structure, the rearward link having an effectively greater length than the forward link. A novel fluid circuit is also provided to resiliently resist movement between the seat and a supporting base structure.
28 Citations
13 Claims
-
1. An operator seat assembly in a vehicle having a longitudinal axis and an operator station, the seat assembly being disposed in the operator station and comprising a base structure secured to the vehicle, a seat frame for supporting an operator, forward and rearward link means respectively pivoted between said base structure and said seat frame, said rearward link means Being effectively longer than said forward link means, said forward and rearward links forming in combination with said seat frame and said base structure to which they are pivotably affixed an unsymmetric quadrilateral having sides of fixed length, said forward and rearward link means being disposed with their respective linear axes tending to remain in substantial convergence adjacent a relatively remote point located below and in longitudinally spaced apart relation forward of the seat assembly, said point of convergence being preselected with reference to the vehicle, and a resilient means effectively interconnected between said seat frame and said base structure for yieldingly resisting movement of said seat frame relative to said base structure.
-
2. The seat assembly of claim 1 wherein the point of convergence is longitudinally located on the vehicle generally adjacent on oscillation point for the vehicle.
-
3. The seat assembly of claim 1 wherein the operator station and seat assembly are situated generally adjacent one end of the vehicle, said forward and rearward link means being selected and arranged to locate the point of convergence for their axes toward the other end of the vehicle.
-
4. The seat assembly of claim 3 wherein the vehicle is a track-type vehicle and the point of convergence is longitudinally located on the vehicle generally adjacent a tipping point for the vehicle.
-
5. The seat assembly of claim 4 wherein the point of convergence is located generally in longitudinal alignment with and substantially above the tipping point of the vehicle to facilitate movement of the seat frame in response to vertical travel of the vehicle.
-
6. A vehicular seat assembly comprising a seat assembly base, a seat frame for supporting an operator, first and second links providing the only means for guiding movement of said seat frame relative to said seat assembly base, opposite ends of each link being pivotably affixed to said seat frame and said seat assembly base respectively in order to closely control the path of movement for said seat frame relative to said seat assembly base, said first and second links being further disposed in spaced apart relation with their axes tending to remain in substantial convergence adjacent a preselected point located below and in longitudinally spaced apart relation from the seat assembly in order to limit said seat frame to oscillatory motion about the preselected point, said first and second links forming an unsymmetric quadrilateral having sides of fixed length in combination with said seat assembly base and seat frame to which they are pivotably affixed, and a resilient means effectively interconnected between said seat frame and said seat assembly base for resisting movement of said seat frame along the path of movement established relative to said seat assembly base by said first and second links.
-
7. The vehicle of claim 6 wherein the interconnection and arrangement of said first and second links further restricts a forward portion of said seat frame to less verticle travel than a rearward portion of said seat frame during forward and rearward movement thereof.
-
8. The vehicle of claim 6 wherein the preselected point is established with respect to operating and physical characteristics of the vehicle for longitudinal alignment with a reference point relative to the vehicle which experiences minimum vertical movement during operating travel of the vehicle.
-
9. The seat assembly of claim 6 wherein said resilient means comprises a piston which is slidable in a fluid cylinder in response to relative motion between said seat frame and seat assembly base and a fluid accumulator in communication with one end of the cylinder.
-
10. The seat assembly of claim 9 wherein said resilient means further comprises cushioning means for increasing resistance to movement of the piston as it approaches one end of the cylinder in response to downward motion of said seat frame toward said seat asSembly base.
-
11. An operator'"'"''"'"'s seat assembly comprising, a base structure, a seat frame for supporting an operator, an interconnecting linkage coupled between said base and seat frame, and resilient means tending to resist movement of said seat frame relative to said base, said resilient means including a fluid cylinder having a piston slidable therein in response to relative motion between said seat frame and base, a fluid accumulator being in communication with one end of said cylinder by means of a first conduit spaced apart from said cylinder end and a second conduit closely adjacent said cylinder end, said second conduit including restrictive means for further resisting movement of said piston as it approaches said cylinder end.
-
12. The seat assembly of claim 11 further comprising a check valve and parallel restrictive orifice, said check valve permitting fluid from said one cylinder end to enter said accumulator, said parallel restrictive orifice limiting fluid returned from said accumulator to said one cylinder end.
-
13. The seat assembly of claim 12 further comprising a valve operable in response to movement of said seat frame relative to said base for selectively communicating additional fluid under pressure at a controlled rate to said one cylinder end and for selectively communicating fluid from said one cylinder end to the other end of said cylinder at another controlled rate.
Specification