Release tool for telescoping towing arms

• US 5,887,497 A
• Filed: 02/13/1996
• Issued: 03/30/1999
• Est. Priority Date: 02/13/1996
• Status: Expired due to Fees

• Current Assignee: Dethmers Manufacturing Company
• Original Assignee: Dethmers Manufacturing Company
• Inventors: Ensz, Russell M.
• Primary Examiner(s): Smith, James G.
• Application Number:
  US08/600,549
• Time in Patent Office: 1,141 Days
• Field of Search: 29/237, 81/484, 81/488, 81/15.9
• US Class Current: 81/484
• CPC Class Codes: B60D 1/143 characterised by the mounting of the draw-gear on the towed vehicle B60D1/187 takes precedence
• CPC Class Codes: B60D 1/167 consisting of articulated or rigidly assembled bars or tubes forming a V-, Y-, or U-shaped draw gear B60D1/173 takes precedence
• CPC Class Codes: B60D 1/1675 comprising extendable, retractable or foldable members
• CPC Class Codes: B64F 1/224 Towing bars
• CPC Class Codes: Y10T 29/5367 Coupling to conduit

Abstract

A release tool is provided to aid in the unlocking of extending towing arms. The tool is adapted to fit a tow bar assembly that has a telescoping towing arm which is locked in an extended position by a slideable collar. The collar is moveable between a locked position and a released position. When in the locked position, the collar holds catches in engagement with legs of the towing arm to hold the legs fixed relative to each other. When in the released position, the legs are free to telescope relative to each other. Stress can build-up in the towing arms making it difficult to move the collar from the locked position to the released position. The release tool of the present invention provides a mechanical advantage to aid in the movement of the collar from the locked position to the released position. A cam surface on the tool engages the collar and moves it from the locked position to the released position as a handle is rotated about a fulcrum means.

Claims

1. A release tool for use on a locking telescoping towing arm assembly wherein the towing arm has a first leg for operable connection with a towing vehicle and a second leg for operable connection to a towed vehicle, wherein the first and second legs are telescopically joined together, wherein a collar is received about the first leg and is slidable relative to the first leg between a locked position and a released position, wherein when the collar is in the locked position it holds the second leg axially fixed relative to the first leg, and wherein when the collar is in the released position the second leg is free to move telescopically with respect to the first leg, the release tool comprising:

(a) a cam surface for engagement with the collar;

(b) fulcrum means for engagement with the towing arm such that said cam surface is between said fulcrum means and the collar; and

(c) a handle having a first end in operable connection with said cam surface and a second end which is free to rotate between a locking position and a releasing position when the fulcrum means is engaged with the towing arm, said cam surface extending generally in the direction of said handle, said handle rotating said cam surface about said fulcrum means to move the collar between the locked position and the released position as said second end of said handle is moved from said locking position to said releasing position.

2. The release tool according to claim 1, further comprising a stirrup attached to said first end of said handle with a first ear and a second ear extending from opposite sides of said first end of said handle, said fulcrum means being located on said ears.

3. The release tool according to claim 2, wherein:

(a) said first ear has an inner surface and an outer surface opposite from said inner surface;

(b) said second ear has an inner surface and an outer surface opposite from said inner surface of said second ear, said inner surface of said second ear is facing said inner surface of said first ear; and

(c) said fulcrum means are a first fulcrum peg extending from said inner surface of said first ear and a second fulcrum peg extending from said inner surface of said second ear.

4. The release tool according to claim 2, wherein said cam surface comprises:

(a) a first convexly curved edge on said first ear; and

(b) a second convexly curved edge on said second ear.

5. A combination of a tow bar having telescoping towing arms and a release tool for allowing adjustment of the telescoping arms, the combination comprising:

a tow bar comprising a telescoping towing arm having an outer leg and an inner leg;

a latching mechanism for maintaining said towing arm in an extended position during towing, said latching mechanism being adjustable between a locked position that maintains the inner leg fixed relative to the outer leg and a released position for allowing said inner leg to move telescopically with respect to said outer leg;

a release tool for engagement with said latching mechanism, said release tool having a handle rotatable about a fulcrum to a releasing position to move said latching mechanism into said released position to allow telescopic movement of said inner leg relative to said outer leg.

6. The combination of a tow bar and a release tool according to claim 5, wherein said latching mechanism comprises a sliding collar, and wherein said release tool further comprises a cam surface for engagement with said sliding collar.

7. The combination of a tow bar and a release tool according to claim 6, wherein said cam surface extends generally in the direction of said handle.

8. The combination of a tow bar and a release tool according to claim 5, wherein said release tool further comprises a stirrup attached to said first end of said handle with a first ear and a second ear extending from opposite sides of said handle, said fulcrum being located on said ears.

9. The combination of a tow bar and a release tool according to claim 8, wherein:

said first ear has an inner surface and an outer surface opposite from said inner surface;

said second ear has an inner surface and an outer surface opposite from said inner surface of said second ear, said inner surface of said second ear facing said inner surface of said first ear; and

said fulcrum comprises a first fulcrum peg extending from said inner surface of said first ear and a second fulcrum peg extending from said inner surface of said second ear.

10. The combination of a tow bar and a release tool according to claim 9, wherein said cam surface comprises:

a first convexly curved edge on said first ear; and

a second convexly curved edge on said second ear.