Contact sensing apparatus and method

• US 4,934,478 A
• Filed: 02/10/1986
• Issued: 06/19/1990
• Est. Priority Date: 02/10/1986
• Status: Expired due to Fees

• Current Assignee: Caterpillar Incorporated
• Original Assignee: Caterpillar Incorporated
• Inventors: Melocik, Grant C., Wible, John E.
• Primary Examiner(s): Marmor, Charles A.
• Assistant Examiner(s): Tyson, Karin
• Application Number:
  US06/827,851
• Time in Patent Office: 1,590 Days
• Field of Search: 180/274, 180/275, 180/277, 180/279, 280/734, 280/735, 340/51, 340/52 H, 340/540, 340/665, 367/135, 367/136, 181/0.5, 181/140, 310/319
• US Class Current: 180/275
• CPC Class Codes: B60K 31/0008 including means for detecting potential obstacles in vehicle path
• CPC Class Codes: B60T 7/22 initiated by contact of vehicle, e.g. bumper, with an external object, e.g. another vehicle , or by means of contactless obstacle detectors mounted on the vehicle
• CPC Class Codes: B60Y 2200/15 Fork lift trucks, Industrial trucks

Abstract

A sensing apparatus capable of delivering a control signal in response to contact between an element of the apparatus and an external object should respond readily to a predetermined level of contact, and should be sensitive along all portions of the contact sensing surface. The instant invention provides a contact sensing apparatus including a conduit having a generally hollow tubular construction and being formed a resilient deformable material. A sonic generator is connected to one end of the conduit and a sonic detector is connected to the other end of the conduit. An electrical circuit is connected to the sonic generator and sonic detector, and is adapted to controllably produce a control signal in response to contact between the conduit and an external object. The instant invention is advantageously free from electro-mechanical switches and optical devices likely to be contaminated when used in an industrial environment, and requires no seals or other precautions necessary to contain pressure or fluid within the conduit.

Claims

1. A contact sensing apparatus for producing a control signal in response to contact between an element of said sensing apparatus and an external object, comprising:

generator means for producing an acoustical signal;

detector means for receiving said acoustical signal and producing an electrical signal having a magnitude responsive to the intensity of said received acoustical signal;

deformable hollow conduit means for controllably conducting said acoustical signal from said generator means to said detector means; and

circuit means for receiving said electrical signal and producing a control signal in response to said electrical signal having at least a predetermined magnitude, wherein said circuit means includes a first comparator means for producing a duty cycle signal in response to said electrical signal magnitude exceeding a predetermined value, an integrator means for producing a trigger signal in response to said duty cycle signal, and a second comparator means for producing said control signal in response to said trigger signal exceeding a predetermined value.

2. A contact sensing apparatus for delivering a control signal to a control system of a vehicle in response to contact between an element of said sensing apparatus and an external object, comprising:

generator means for producing an acoustical signal;

detector means for receiving said acoustical signal and producing an electrical signal having a magnitude responsive to the intensity of said received acoustical signal;

deformable hollow conduit means for controllably conducting said acoustical signal from said generator means to said detector means, said conduit means being positioned along an exterior portion of said vehicle; and

circuit means for receiving said electrical signal, producing a control signal in response to said electrical signal having at least a predetermined magnitude and delivering said control signal to said vehicle control system to controllably stop said vehicle in response to receiving said control signal, wherein said circuit means includes a first comparator means for producing a duty cycle signal in response to said electrical signal magnitude exceeding a predetermined value, an integrator means for producing a trigger signal in response to said duty cycle signal, and a second comparator means for producing said control signal in response to said trigger signal exceeding a predetermined value.

3. A contact sensing apparatus, as set forth in claim 2, wherein said conduit means extends generally horizontally circumferentially around a peripheral portion of said vehicle.

4. A contact sensing apparatus, as set forth in claim 2, wherein said vehicle includes a bumper, and said conduit means is mounted on an outwardly facing surface portion of said bumper.

5. A contact sensing apparatus for delivering a control signal to a control system of a vehicle in response to contact between an element of said sensing apparatus and an external object, comprising:

a conduit having first and second ends and being positioned along an exterior portion of said vehicle, said conduit being of a generally hollow tubular construction and being formed from a resilient deformable material;

a sonic generator connected to one of said first and second ends of said conduit;

a sonic detector connected to the other of said first and second ends of said conduit; and

an electrical circuit connected to said sonic generator and said sonic detector, and adapted to controllably produce said control signal wherein said electrical circuit includes a first comparator circuit having an output terminal, and an input terminal connected to said sonic detector;

an integrator circuit having an output terminal, and an input terminal connected to said first comparator output terminal; and

a second comparator circuit having an input terminal connected to said integrator circuit output terminal, and an output terminal connected to said vehicle control system.