Lifting vehicle and method of operating the vehicle

• US 5,722,511 A
• Filed: 10/13/1995
• Issued: 03/03/1998
• Est. Priority Date: 10/17/1994
• Status: Expired due to Fees

• Current Assignee: Bishamon Industries Corporation
• Original Assignee: Bishamon Industries Corporation
• Inventors: Wakamiya, Koji
• Primary Examiner(s): NOLAND, KENNETH W
• Application Number:
  US08/542,672
• Time in Patent Office: 872 Days
• Field of Search: 187/231, 187/232, 187/237, 187/233, 414/630, 414/631
• US Class Current: 187/231
• CPC Class Codes: B66F 9/07522 Variable length or width chassis

Abstract

A forklift is supported for movement by a pair of elongated wheeled members. The wheeled members are shiftable towards and away from one another to permit the handling of different types of loads. Each of the wheeled members has a rear wheel in the form of a caster as well as two front wheels. The front wheels of a wheeled member can be lowered and raised in such a manner that one of the front wheels is lifted from the ground as the other front wheel is moved down into contact with the ground. A first front wheel of each wheeled member is arranged to roll forwards and backwards while the second front wheel rolls sideways. During the transportation of loads from one location to another, the first front wheels are in contact with the ground. When the wheeled members are to be moved towards or away from one another, the second front wheels are brought into contact with the ground.

Claims

1. A lifting vehicle, comprising a mount;

a lifting mechanism on said mount;

a pair of bearing members for moving said mount over a support surface, said bearing members projecting to one side of said mount, and each of said bearing members including a first rolling element rotatable about a first axis and a second rolling element rotatable about a second axis transverse to the respective first axis, each of said rolling elements having a lowered position in which the respective rolling element is arranged to contact the support surface and a raised position in which the respective rolling element is arranged to be out of contact with the support surface, and each of said bearing members further including a displacing mechanism for moving the associated rolling elements between the raised and lowered positions; and

a shifting mechanism for moving said bearing members towards and away from one another.

2. The vehicle of claim 1, wherein said bearing members are elongated and substantially parallel to one another.

3. The vehicle of claim 1, wherein said shifting mechanism is designed to move said bearing members synchronously.

4. The vehicle of claim 3, wherein said shifting mechanism comprises a first carrier fast with one of said bearing members, a second carrier fast with the other of said bearing members, and a rack-and-pinion mechanism connecting said carriers to one another.

5. The vehicle of claim 4, wherein said rack-and-pinion mechanism comprises a rack on each of said carriers, and a pinion in engagement with said racks.

6. The vehicle of claim 4, wherein each of said carriers comprises a rail and said rails are substantially parallel to one another.

7. The vehicle of claim 4, further comprising an actuator connected to and arranged to move one of said carriers.

8. A lifting vehicle, comprising a mount;

a lifting mechanism on said mount;

a pair of bearing members for moving said mount over a support surface, said bearing members projecting to one side of said mount, and each of said bearing members including a first rolling element rotatable about a first axis and a second rolling element rotatable about a second axis transverse to the respective first axis, each of said rolling elements having a lowered position in which the respective rolling element is arranged to contact the support surface and a raised position in which the respective rolling element is arranged to be out of contact with the support surface, and each of said bearing members further including a displacing mechanism for moving the associated rolling elements between the raised and lowered positions, each of said displacing mechanisms being designed so that the associated first rolling element is moved to the lowered position in response to movement of the corresponding second rolling element to the raised position and the associated first rolling element is moved to the raised position in response to movement of the corresponding second rolling element to the lowered position; and

a shifting mechanism for moving said bearing members towards and away from one another.

9. A lifting vehicle, comprising a mount;

a lifting mechanism on said mount;

a pair of bearing members for moving said mount over a support surface, said bearing members projecting to one side of said mount, and each of said bearing members including a first rolling element rotatable about a first axis and a second rolling element rotatable about a second axis transverse to the respective first axis, each of said rolling elements having a lowered position in which the respective rolling element is arranged to contact the support surface and a raised position in which the respective rolling element is arranged to be out of contact with the support surface, and each of said bearing members further including a displacing mechanism for moving the associated rolling elements between the raised and lowered positions;

an actuator for actuating said displacing mechanisms in such a manner that said first rolling elements assume the raised and lowered positions together and said second rolling elements assume the raised and lowered positions together; and

a shifting mechanism for moving said bearing members towards and away from one another.