VEHICLE-TRAILER ANGULAR POSITION SENSOR AND INDICATOR

• US 3,833,928 A
• Filed: 01/08/1973
• Issued: 09/03/1974
• Est. Priority Date: 01/08/1973
• Status: Expired due to Term

• Current Assignee: Stephen E. Gavit, William E. Stenson
• Original Assignee: Stephen E. Gavit, William E. Stenson
• Inventors: Gavit, Stephen E., Stenson, William E.
• Primary Examiner(s): Swann, III, Glen R.
• Application Number:
  US05/321,858
• Time in Patent Office: 603 Days
• Field of Search: 340/52R,282 180/103
• US Class Current: 340/431
• CPC Class Codes: B60D 1/06 Ball-and-socket hitches , e.g. constructional details, auxiliary devices, their arrangement on the vehicle
• CPC Class Codes: B60Q 1/305 Indicating devices for towed vehicles

Abstract

A device for sensing and indicating the relative angular relationship between a tow vehicle and a trailer universally connected to the tow vehicle by a ball hitch assembly includes a sensor adapted to be mounted directly beneath the ball portion of the hitch assembly to function electro-mechanically in varying a potential output from the sensor dependent upon the relative angular relationship between the trailer and the tow vehicle whereby such angular relationship is displayed on an electrically responsive visual indicator mounted preferably on the control panel of the tow vehicle.

Claims

1. A device for sensing and indicating the relative angular relationship between a tow vehicle and trailer connected thereto by a hitch assembly, the tow vehicle having the male portion of thE hitch assembly fixedly mounted thereon and the trailer having the female portion of the hitch assembly, comprising in combination:

sensor means mounted on said hitch assembly, an outer member of said sensor means having a circular opening therein and being attached to either one of said trailer and tow vehicle for movement therewith, an inner member of said sensor means mounted in said circular opening of the outer member for pivotal movement within said outer member and attached to the other of said trailer and tow vehicle for movement therewith such that pivotal movement of the trailer relative to the vehicle will effect pivotal movement of the outer member relative to the inner member, an electrical resistance element of said sensor mounted between said outer member and said inner member and fixed to one of said members so as to follow movement of one of said members relative to the other of said members, a contact element of said sensor fixed relative to said other member and disposed in contact with said resistance element to advance along the resistance element upon relative movement between the outer member and the inner member, and an electrically responsive indicator means electrically connected to said sensor means and to an electrical power source, operative to indicate the relative angular relationship between said trailer and tow vehicle.

2. The device of claim 1 wherein said inner member is fixed to said male portion and is concentric with a longitudinal axis of the male portion, and wherein said outer member and said inner member are disposed in a plane normal to said longitudinal axis, and further including a rigid connection rod on said outer member extending adjacent to said female portion of the hitch assembly and connection means for releasably connecting the connection rod to the female portion whereby said outer member follows movement of the trailer.

3. The device of claim 2, wherein said inner member has an outwardly directed peripheral groove for reception of said resistance element, and means for connecting the resistance element to the inner member for unitary movement therewith.

4. The device of claim 3, wherein said outer member has a passage therein communicating with said circular opening and wherein the contact element is disposed within said passage, and further including insulating means for retaining said contact element in the passage and in engagement with said resistance element.

5. The device of claim 4 wherein said passage communicates with said circular opening along a path which is tangent to the inner surface of the circular opening.

6. The device of claim 4 wherein said inner member and one end of said resistance element are electrically grounded, said contact element is connected to one terminal of the said indicator means, and another terminal of the indicator means is connected to the electrical power source whereby the relative positions of the inner and outer members, which correspond to the relative positions of the tow vehicle and trailer, are indicated on the indicator means.

7. A device for sensing and visually indicating the relative angular relationship between a tow vehicle and a trailer connected to the tow vehicle by a hitch assembly for universal movement relative thereto, the hitch assembly including a ball portion with a spherical head, a base beneath the head, and a reduced diameter depending shaft adapted to be passed through a rear portion of the tow vehicle and tightened thereagainst by tightening means, and a socket portion adapted to receive the spherical head and which is carried by the forward end of a tongue on the trailer, comprising in combination:

a first member immovably mounted concentrically on the shaft of the said ball portion between said base and the rear portion of the tow vehicle, a second member mounted on said first member for pivotal movement relative thereto, connection means mounted on said second member and releasably connected to the tongue of the trailer to follow movement of the tongue, rheostat means comprising a resistance element and a movable contact element one of said resistance and contact elements being operatively connected to each of said first and second members, the resistance value of said rheostat means being dependent upon the relative angular relationship between said first and second members, and electrically responsive visual indicator means electrically connected to said rheostat means and to an electrical power source to visually indicate the relative angular relationship between said tow vehicle and trailer.

8. A device for sensing and visually indicating the relative angular relationship between a tow vehicle and a trailer pivotally connected to the tow vehicle by a hitch assembly, the hitch assembly including a ball portion with a spherical head, a base beneath the head, and a reduced diameter depending shaft passing through a rear portion of the tow vehicle for attachment thereto by drawing the base tightly against the rear portion, and a socket portion adapted to receive the spherical head and which is carried by the forward end of a tongue on a trailer, comprising in combination:

sensor means mounted on said hitch assembly, an inner member of the sensor means having a substantially cylindrical configuration, a central axial passage through the inner member of a corresponding diameter to the shaft of the ball portion of the hitch assembly, said inner member being mounted on the shaft immediately beneath the base of the ball portion in concentric relation to a longitudinal axis of the ball portion and tightened against the rear portion so as to be immovable relative to the ball portion, an outer member of the sensor means having a circular opening therein to pivotally receive the inner member, lock means on said sensor pivotally interconnecting the inner member and the outer member to prevent relative axial movement with the inner member extending downwardly below the outer member thereby spacing the outer member from the rear portion of the tow vehicle so that the outer member is movable relative to the tow vehicle, connection means on said sensor interconnecting the outer member to the tongue of the trailer so that the outer member pivots about the inner member and said longitudinal axis in correspondence to pivotal movement of the trailer relative to the tow vehicle about said longitudinal axis, an elongated resistance element of said sensor mounted between said inner member and said outer member and fixed to said inner member for unitary movement therewith, a contact element of said sensor mounted on said outer member for movable engagement with said resistance element along the length of the resistance element, and electrically responsive visual indicator means electrically connected to said contact element and to an electrical power source for visually indicating the relative angular relationship between said tow vehicle and trailer.

9. The device of claim 8 wherein said inner member has an outwardly directed peripheral groove in which the resistance element is seated, and further including means for insulating said resistance element from the inner member except at one end of the resistance element, and means at said one end for mechanically and electrically connecting the resistance element to the inner member.

10. The device of claim 9, further including a passage in said outer member communicating with said circular opening for reception of the contact element, and insulating means for retaining said contact element in the passage and in engagement with said resistance element.

11. The device of claim 10, wherein said inner member is electrically grounded, said contact element is connected to the electrical power source and to one terminal of the visual indicator means, and another terminal of the visual indicator means is connected to the electrical power source whereby the relative positions of the inner and outer members, which correspond to the relative positions of the tow vehicle and trailer, are visually indicated on the indicator device.

12. The device of claim 10, wherein said inner member has a second outwardly directed peripheral groove and said outer member has an inwardly directed peripheral groove, and wherein said lock means comprises a split ring seated in said second peripheral groove of the inner member and said peripheral groove of the outer member to prevent relative axial movement between the inner and outer members.