Patent ID: 6331010
Filing Date: 2001-12-18
Classification: B60G,B66F,F15B,F16C,F16F

Abstract:
An industrial vehicle having a frame and an axle pivotally connected with the frame, said vehicle comprising:a center shaft about which the axle pivots, said center shaft having an axis, wherein said frame is connected with the axle by the center;a first bracket fixed to the frame;a second bracket fixed to the axle;a cylinder located between the frame and the axle, said cylinder being arranged to selectively extend and retract to absorb the pivotal motion of the axle and being pivotable about axes that are normal to the axis of the center shaft, said cylinder having (i) a first end pivotally coupled to the first bracket and including a first through hole having an inner surface; (ii) a second end pivotally coupled to the second bracket; (iii) a cylinder case; (iv) a piston located in the case; (v) a first piston rod connected with the piston and slidably connected to the first end; (vi) a second piston rod connected with the second end; and (vii) two hydraulic chambers selectively receiving and discharging hydraulic fluid to extend and retract the cylinder, respectively, wherein the piston is located between the two hydraulic chambers, and the piston has a first pressure-receiving area that faces one of the two hydraulic chambers and a second pressure-receiving area that faces the other of the two hydraulic chambers, and wherein the first pressure-receiving area is substantially equal in size to the second pressure-receiving area; andjoints that couple the cylinder with the frame and the axle, said joints including:a first coupler for coupling the first end to the first bracket, said first coupler including: (i) a first support shaft supported by the first bracket, wherein the first support shaft extends through the first through hole; (ii) a collar mounted on the first support shaft, wherein the collar includes a pair of large diameter portions and a small diameter portion located between the large diameter portions; (iii) a convex portion provided with the small diameter portion; and (iv) a concave portion provided with the inner peripheral surface of the first through hole, wherein said concave portion engages and slides with respect to the convex portion; anda second coupler for coupling the second end to the second bracket.