Trailer hitch guide

• US 3,924,257 A
• Filed: 06/21/1973
• Issued: 12/02/1975
• Est. Priority Date: 06/21/1973
• Status: Expired due to Term

• Current Assignee: Jack E. Roberts
• Original Assignee: Jack E. Roberts
• Inventors: Roberts, Jack E.
• Primary Examiner(s): Tubbesing, T. H.
• Assistant Examiner(s): Berger, Richard E.
• Application Number:
  US05/372,068
• Time in Patent Office: 894 Days
• Field of Search: 343/112R,112D 180/98 244/161 340/51,52R,282,195,275 280/477
• US Class Current: 340/431
• 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: B62D 13/06 for backing a normally drawn trailer
• CPC Class Codes: G01B 7/31 for testing the alignment of axes
• CPC Class Codes: G01D 5/225 by influencing the mutual induction between the two coils

Abstract

A guidance system for assisting the operator of a towing vehicle, during the backing of the latter, provides a transmitter on the vehicle to be towed and a receiver on the towing vehicle which receives a signal from the transmitter and detects from the amplitude and polarity of respective coordinate signals generated thereby, the direction and proximity of the towing vehicle with respect to the towed vehicle.

Claims

1. A guidance system for indicating the direction of relative movement and proximity of a towing vehicle to a towed vehicle comprising coupling means for connecting the rearmost end of a towing vehicle to the forwardmost end of a towed vehicle, including a first coupling element on said towing vehicle and a second coupling element on said towed vehicle, whereby the position of said first coupling element with respect to said second coupling element changes with relative movement of said vehicles, transmitter means positioned on said towed vehicle for transmitting a signal forwardly from said forwardmost end of said towed vehicle with a prescribed directional orientation with respect to said towed vehicle, receiver means positioned on said towing vehicle for detecting the angulaR relationship and proximity of said receiver means to said transmitter means from the directional orientation of said transmitted signal, said receiver means including a direction sensor comprising first and second coils arranged transversely and in parallel to the longitudinal axis of said towing vehicle, respectively, first and second capacitors connected across said first and second coils, respectively, to form circuits therewith which are tuned to the frequency of the signal transmitted by said transmitter means, first and second amplifiers connected to said first and second coils, respectively, a phase-amplitude detector having first and second inputs connected to the outputs of said first and second amplifiers, respectively, and providing a first output signal having an amplitude and polarity indicative of the magnitude and direction of misalignment between the longitudinal axes of said towing and towed vehicles, an automatic gain control circuit connected to the output of said second amplifier for controlling the gain thereof, and a proximity detector connected to said automatic gain control circuit for providing a second signal indicating the proximity of said receiver means to said transmitter means by detecting the amplitude of the current derived from said second coil, and indicator means connected to said receiver means for indicating the angular relationship between said vehicles and the proximity of said towing vehicle to said towed vehicle in response to the first and second signals derived from the output of said receiver means.

2. A guidance system as defined in claim 1, wherein said transmitter means includes an oscillator and a field generating coil connected to said oscillator and oriented to generate a field having said prescribed directional orientation with respect to said towed vehicle.

3. A guidance system as defined in claim 2, wherein said field generating coil has its longitudinal axis parallel to the transverse axis of said towed vehicle so as to generate said field in the forward direction along the longitudinal axis of said towed vehicle.

4. A guidance system as defined in claim 1, wherein said indicator means includes a first indicator connected to said proximity detector for providing an indication when said first and second coupling elements are in alignment.

5. A guidance system as defined in claim 4, wherein said indicator means further includes a second indicator responsive to said first signal for indicating the direction and extent of misalignment between said towing vehicle and said towed vehicle.

6. In a guidance system for assisting the operator of a towing vehicle, a method comprising the steps of:

a. providing respective coupling elements on said towing vehicle and a towed vehicle for coupling said towing vehicle to said towed vehicle, b. transmitting from said towed vehicle a signal having a prescribed directional orientation with respect to said towed vehicle, c. receiving in said towing vehicle said signal from said towed vehicle, d. analyzing said received signal to detect the angular relationship and proximity of said towed vehicle to said towing vehicle, e. indicating to said operator of said towing vehicle said detected angular relationship and proximity of said towed vehicle to said towing vehicle, f. repositioning said towing vehicle with respect to said towed vehicle in response to said indicating so as to diminish the angular deviation and proximity of said towed vehicle with respect to said towing vehicle, g. repeating steps (b) through (f) until said analyzing and indicating infer that the longitudinal axes of said towing and towed vehicles are aligned and said coupling elements are aligned, and h. coupling said towing vehicle to said towed vehicle when said longitudinal axes of said towing and towed vehicles are aligned and said coupling elements are aligned.