US 4,365,921 A · Forklift vehicle

Abstract

A self propelled forklift vehicle having a frame formed by two spaced parallel longitudinal frame members and a rear transverse frame member. The fork carriage is movable forwardly and rearwardly on the longitudinal frame members, along the path of the machine, and carries a fork tower and forks. The forks can be forced below the vehicle to raise the vehicle up beneath the rear of a trailer for transport. The vehicle's rear wheels, which steer and drive the vehicle, are closely spaced and tiltable from side to side to allow for rough terrain, with the operator seat and motor on opposite sides thereof to balance each other. A manually operated split pulley drive allows creeping of the vehicle at a closely controlled low speed. The fork tines include erectable rollers to support part of the vehicle weight when the forks carry a forwardly extended load, to prevent tipping. A front gate causes discharge of the contents of a pallet onto the ground when the fork carriage is retracted. An automatic centering mechanism returns the rear driving wheels to either front driving or rear driving position as selected by the operator.

Claims35

Dependent claims

A self propelled forklift vehicle comprising:

(a) a frame defining an elongated space open at one end thereof and extending to the ground,
(b) wheels mounted on said frame for supporting and driving said vehicle,
(c) a fork tower, and forks mounted on said fork tower,
(d) means mounting said fork tower on said frame with said forks positioned in said space and for horizontal movement of said fork tower on said frame,
(e) power means connected between said fork tower and said frame and operable for moving said fork tower on said frame to move said forks horizontally through said space,
(f) means connected between said fork tower and said forks for raising and lowering said forks and for driving said forks substantially below the level of the bottoms of said wheels, whereby to raise said vehicle above the ground on said forks, so that said vehicle can be moved by driving said forks below the bottoms of said wheels and then operating said power means to produce relative movement between said fork tower and said frame while said vehicle is thus raised.

3 more elements

A self propelled forklift vehicle adapted for travel over the ground along a forward and rearward path of travel and comprising:

(a) a frame having a pair of longitudinal parallel frame members spaced laterally apart and extending along said path of travel and defining a space therebetween, said space being elongated in the direction of said path of travel and being open at the front ends of said frame members and extending to said ground,
(b) two front wheels, one connected to the outside of each frame member near the front thereof,
(c) rear wheel means connected to said frame members,
(d) a fork carriage extending across said space and mounted on said frame members for movement forwardly and rearwardly along said frame members,
(e) a fork tower mounted on said fork carriage, said fork tower having forwardly facing forks mounted thereon, said forks being positioned in said space,
(f) power means connected to said fork carriage and to said frame members for moving said fork carriage forwardly and rearwardly along said frame members to move said forks forwardly and rearwardly through said space,
(g) said fork tower including means for raising and lowering said forks, and for driving said forks substantially below the bottoms of said wheels and said wheel means, whereby to raise said vehicle above the ground on said forks, so that said vehicle can be moved by driving said forks below the bottoms of said wheels and said wheel means and then operating said power means to produce relative movement along said path of travel between said fork carriage and said frame member while said vehicle is thus raised.

4 more elements

A self propelled forklift vehicle adapted for travel along a forward and rearward path of travel and comprising:

(a) a frame having a pair of longitudinal parallel frame members spaced laterally apart and extending along said path of travel and defining a space therebetween, said space being open at the front ends of said frame members,
(b) two front wheels, one connected to the outside of each frame member near the front thereof,
(c) rear wheel means connected to said frame members,
(d) a fork carriage extending across said space and mounted on said frame members for movement forwardly and rearwardly along said frame members,
(e) a fork tower mounted on said fork carriage, said fork tower having forwardly facing forks mounted thereon, said fork tower including means for raising and lowering said forks, and for driving said forks substantially below the bottoms of said wheels and said wheel means, whereby to raise said vehicle above the ground, (f) power means connected to said fork carriage and to said frame members for moving said fork carriage forwardly and rearwardly along said frame members,
(g) each frame member including a set of rack teeth, and said power means including a drive gear mounted on said fork carriage and engaging said rack teeth, and motor means connected to said fork carriage for rotating said drive gear,
(h) said fork carriage including a transverse member extending laterally between said frame members, and two carriage side members one secured to each end of said transverse member, and said fork tower including a drive shaft extending through said transverse member, a said drive gear connected to each end of said drive shaft, each drive gear being in engagement with a set of said rack teeth, chain and sprocket means connected to said drive shaft for rotating said drive shaft and motor connected to said chain and sprocket means.

4 more elements

A self propelled forklift vehicle adapted for travel along a forward and rearward path of travel and comprising:

(a) a frame having a pair of longitudinal parallel frame members spaced laterally apart and extending along said path of travel and defining a space therebetween, said space being open at the front ends of said frame members,
(b) two front wheels, one connected to the outside of each frame member near the front thereof,
(c) rear wheel means connected to said frame members,
(d) a fork carriage extending across said space and mounted on said frame members for movement forwardly and rearwardly along said frame members,
(e) a fork tower mounted on said fork carriage, said fork tower having forwardly facing forks mounted thereon, said fork tower including means for raising and lowering said forks, and for driving said forks substantially below the bottoms of said wheels and said wheel means, whereby to raise said vehicle above the ground,
(f) power means connected to said fork carriage and to said frame members for moving said fork carriage forwardly and rearwardly along said frame members,
(g) a gate, means mounted on said vehicle for selectively supporting said gate transversely across said forks and adjacent the front ends of said longitudinal frame members, and blocking means coupled to said longitudinal frame members adjacent the front ends thereof for blocking rear movement of said gate when said gate is located transversely across said forks so that when said fork carriage is moved rearwardly, said gate will block movement of the contents of the pallet located on said forks, thereby effecting discharge of said contents from said pallet.

4 more elements

A self propelled forklift vehicle comprising:

(a) a frame having a pair of parallel frame members spaced apart and defining a space therebetween for receiving a pallet, said space having an open front end, bounded by the fronts of said frame members,
(b) a fork carriage extending across said space and mounted on said frame members for movement along said frame members,
(c) a fork tower mounted on said fork carriage, said fork tower having forks mounted thereon and facing said open end of said open end of said space to support said pallet, said fork tower including means for raising and lowering said forks,
(d) power means connected to said fork carriage and to said frame members for moving said fork carriage along said frame members, towards and away from said open end,
(e) a pair of stops coupled to said frame members adjacent the fronts thereof,
(f) a gate,
(g) and means for supporting said gate in front of said stops and extending across said forks, so that when said gate is located between the contents of a pallet on said forks and said stops and then said fork carriage is withdrawn rearwardly into said space, movement of said gate rearwardly will be prevented by said stops and said gate will act to discharge the contents of said pallet onto the ground.

4 more elements

A self propelled forklift vehicle adapted for travel along a forward and rearward path of travel and comprising:

(a) a frame having a pair of longitudinal parallel frame members spaced laterally apart and extending along said path of travel and defining a space therebetween, said space being open at the front ends of said frame members,
(b) two front wheels, one connected to the outside of each frame member near the front thereof,
(c) rear wheel means connected to said frame members,
(d) a fork carriage extending across said space and mounted on said frame members for movement forwardly and rearwardly along said frame members,
(e) a fork tower mounted on said fork carriage, said fork tower having forwardly facing forks mounted thereon, said fork tower including means for raising and lowering said forks,
(f) power means connected to said fork carriage and to said frame members for moving said fork carriage forwardly and rearwardly along said frame members,
(g) a set of downwardly facing rack teeth mounted on each frame member,
(h) said power means including a drive gear mounted on said fork carriage and engaging said rack teeth, and motor means connected to said fork carriage for rotating said drive gear,
(i) said motor means being a hydraulic motor having a drive sprocket, said power means including a second drive sprocket connected to said drive gear, a chain extending between said drive sprockets, and enclosure means enclosing said drive sprockets and chain.

6 more elements

Dependencies are inferred from the claim text.

Forklift vehicle

Life of this patent

Forklift vehicle

Life of this patent

Abstract

Claims35