Trailer having secondary wheel attached to adjustable leg

• US 8,500,167 B2
• Filed: 07/07/2010
• Issued: 08/06/2013
• Est. Priority Date: 07/07/2009
• Status: Active Grant

• Current Assignee: Marcos Angel Diaz
• Original Assignee: Marcos Angel Diaz
• Inventors: Diaz, Marcos Angel
• Primary Examiner(s): Walters, John
• Assistant Examiner(s): TRIGGS, JAMES J
• Application Number:
  US13/382,614
• Publication Number:
  US 20120098243A1
• Time in Patent Office: 1,126 Days
• Field of Search: 280/766.1, 280/767, 280/755, 280/763.1, 280/764.1, 280/765.1, 280/762, 254/423, 254/418, 254/420, 254/116, 254/118, 254/119, 254/412, 254/425, 254/427
• US Class Current: 280/766.1
• CPC Class Codes: B60S 9/215 driven by an auxiliary motor

Abstract

A trailer has a body, a primary wheel, and an adjustable leg for providing secondary support. The leg has a terminal end moveable between retracted and extended positions and a secondary wheel rotatably attached to the terminal end, such that the secondary wheel is off the ground when the terminal end is in the retracted position and is in contact with the ground when the terminal end is in the extended position. A pneumatic or hydraulic drive unit is mounted on the trailer body for adjusting the leg to move the terminal end between the extended and retracted positions. A drivetrain is mounted on the trailer body and operatively connected to the secondary wheel for driving the secondary wheel. A controller controls operation of the drive unit to automatically adjust the leg to maintain balance of the trailer, and controls operation of the drivetrain to drive the trailer.

Claims

1. A trailer comprising:

a trailer body;

a hitch for coupling said trailer to a towing vehicle;

a primary wheel mounted under said trailer body and in contact with the ground for supporting said trailer and allowing said trailer to be towed;

an adjustable leg mounted under said trailer body between said hitch and said primary wheel for providing secondary support of said trailer, said leg comprising;

a terminal end moveable between a retracted position and an extended position, and

a secondary wheel rotatably attached to said terminal end of said leg such that said secondary wheel is off the ground when said terminal end is in said retracted position and is in contact with the ground when said terminal end is in said extended position;

a pneumatic or hydraulic drive unit mounted on said trailer body for adjusting said leg to move said terminal end of said leg between said extended and retracted positions;

a drivetrain mounted on said trailer body and operatively connected to said secondary wheel for driving said secondary wheel;

a controller for controlling operation of said pneumatic or hydraulic drive unit to automatically adjust said leg to maintain balance of said trailer, and for controlling operation of said drivetrain to drive said trailer when said secondary wheel is in contact with the ground.

2. The trailer of claim 1, wherein said pneumatic or hydraulic drive unit comprises a pneumatic or hydraulic cylinder, and a pneumatic or hydraulic generator for driving said cylinder.

3. The trailer of claim 2, wherein said leg comprises said cylinder and said terminal end of said leg is extendable downwards from said retracted position.

4. The trailer of claim 2, wherein said leg is rotatably attached to said trailer body, and said cylinder is attached to said trailer body and said leg to rotate said leg so as to move said terminal end of said leg between said retracted position and said extended position.

5. The trailer of claim 2, wherein said cylinder is a pneumatic cylinder and said generator comprises a compressor.

6. The trailer of claim 1, comprising a foot mounted at said terminal end of said leg, said foot having a generally flat bottom surface and being movable between a raised position and a lowered position, wherein when said foot is in said raised position said secondary wheel is allowed to contact the ground to support said trailer, and when said foot is in said lowered position said bottom surface of said foot contacts the ground to support said trailer.

7. The trailer of claim 6, wherein said foot comprises a generally U- or L-shaped body.

8. The trailer of claim 6, comprising a locking mechanism for selectively locking said foot in one of said raised and lowered positions.

9. The trailer of claim 1, wherein said controller comprises a sensor for sensing a degree of tilting of said trailer body.

10. The trailer of claim 1, wherein said controller comprises a remote control for operating said controller.

11. The trailer of claim 1, wherein said drivetrain comprises a pneumatic engine.

12. The trailer of claim 11, wherein said drivetrain comprises a chain drive for transmitting a rotational torque from said engine to said secondary wheel.

13. The trailer of claim 1, comprising an airbag mounted under said trailer body above said primary wheel, a roller frame attached to said airbag and a roller rotatably supported on said roller frame, such that when said airbag is depleted said roller is spaced away from said primary wheel, and when said airbag is expanded said roller contacts said primary wheel to provide additional support for said trailer body.

14. The trailer of claim 1, comprising an air suspension, said air suspension comprising at least two air springs, and an air supply connected to each one of said at least two air springs for independently supplying or withdrawing air from said each air spring, and a controller for controlling independent supply and withdrawal of air from said each air spring in response to tilting of said trailer body.

15. The trailer of claim 1, comprising a plurality of primary wheels.

16. The trailer of claim 1, comprising a plurality of adjustable legs and a plurality of secondary wheels each rotatably mounted on a terminal end of one of said legs.