Apparatus for sensing and indicating the angular relationship between a towing and a towed vehicle

• US 4,122,390 A
• Filed: 02/06/1978
• Issued: 10/24/1978
• Est. Priority Date: 10/28/1976
• Status: Expired due to Term

• Current Assignee: Frank L. Trapschuh, Gerhard Kollitz
• Original Assignee: Frank L. Trapschuh, Gerhard Kollitz
• Inventors: Kollitz, Gerhard, Trapschuh, Frank L.
• Primary Examiner(s): Krawczewicz, Stanley T.
• Application Number:
  US05/875,184
• Time in Patent Office: 260 Days
• Field of Search: 324/65 R, 280/432, 280/292, 280/446 R, 340/52 R, 340/61, 340/70, 340/275, 340/282
• US Class Current: 340/870.38
• CPC Class Codes: B60D 1/065 characterised by the hitch mechanism
• CPC Class Codes: B60D 1/36 for facilitating connection, e.g. hitch catchers , visual guide means, signalling aids B60D1/465 takes precedence; vehicle signalling in general B60Q; optical arrangements specially adapted for viewing trailer-hitches B60R1/003
• CPC Class Codes: B60D 1/58 Auxiliary devices
• CPC Class Codes: G01D 5/165 by relative movement of a point of contact or actuation and a resistive track
• CPC Class Codes: G01R 17/105 for measuring impedance or resistance

Abstract

A sensing apparatus having a stationary part and a movable part which rotates in relation to the stationary part, is attached to both a towing and the towed vehicle so that the stationary part is fixedly attached to one vehicle and the movable part is relatively fixedly attached to the other vehicle. The angular relationship between the towing and the towed vehicle is reflected in the angular relationship between the stationary part and the movable part of the sensing apparatus. This angular relationship is electrically sensed and displayed on an indicating device in the towing vehicle.

Claims

1. Apparatus for sensing and indicating the angular relationship between a towing and a towed vehicle, wherein the towing vehicle includes a ball hitch assembly comprising a ball connected to a shaft which is attached to the towing vehicle, said apparatus comprising:

a variable resistor having a body portion, a shaft rotatably mounted to said body portion so that the resistance of the variable resistor is varied as the shaft is turned;

a plate having an orthogonal portion and an aperture, the body part of the variable resistor being rigidly attached to said plate, said shaft protruding through the aperture therein;

a second plate having a circular aperture, said second plate being mounted to the towing vehicle by sliding the shaft of the ball hitch assembly of the towing vehicle through said circular aperture, said second plate also having an orthogonal portion, said orthogonal portion having an aperture into which is placed the orthogonal portion of said first plate so as to form a hinge;

a feeler rigidly connected to the shaft of the variable resistor;

means for fixedly but removably attaching said feeler to the towed vehicle thereby providing for rotational movement of the shaft in relation to the body portion of said variable resistor as the towed vehicle moves in relation to the towing vehicle; and

an indicator means electrically responsive to the movement between the shaft and body portions of said variable resistor for representatively indicating the angular relationship between the towing and towed vehicle.

2. The apparatus of claim 1 wherein said indicator means includes:

a current-responsive indicating means; and

a resistive bridge circuit, said current-responsive indicating means being connected to measure current flow in said circuit, the variable resistor being connected to said circuit.