AUTOMATICALLY STEERED SELF-PROPELLED VEHICLE

• US 3,750,833 A
• Filed: 10/08/1971
• Issued: 08/07/1973
• Est. Priority Date: 10/09/1970
• Status: Expired due to Term

• Current Assignee: Eberhard Kahl
• Original Assignee: Eberhard Kahl
• Inventors: Kahl, Eberhard
• Primary Examiner(s): Forlenza, Gerald M.
• Assistant Examiner(s): Abraham, George F.
• Application Number:
  US05/187,759
• Time in Patent Office: 669 Days
• Field of Search: 180/97,79,79.1 46/244R,212
• US Class Current: 180/401
• CPC Class Codes: B62D 1/26 mechanical, e.g. by a non-load-bearing guide railways B61
• CPC Class Codes: G05D 1/0227 using mechanical sensing means, e.g. for sensing treated area

Abstract

An automatically steered self-propelled vehicle for movement over the unobstructed portions of an area having obstructions includes a vehicle frame having wheels mounted thereon and a sensing rail mounted on the frame. The sensing rail is displaceable relative to the frame between a normally extended position and a retracted position upon being urged against an obstruction by the vehicle. A reversible driving motor is connected to the wheels for rotating the wheels in a forward and a reverse direction. A reversible steering motor is connected to the wheels for displacing the same between a normally straight and a sideward position oriented 90* from the straight position. A storage device for monitoring the distance travelled by the vehicle in the lateral direction is connected to the steering motor and to the driving motor for regulating the operation of these two motors. The steering motor is rotatable in one direction to cause the wheels to be displaced to the sideward position in response to the sensing rail achieving the retracted position and the steering motor is rotatable in the other direction to cause the wheels to return to the straight position in response to the sensing rail achieving the extended position. The driving motor is rotatable in one direction to cause the vehicle to move in the forward direction when the wheels are in the straight position and the steering motor is rotatable in the other direction in response to the regulation by the control device and to the wheel positions. The steering motor is adapted to rotate either in the forward or in the reverse directions in response to the wheels returning to the straight position from the lateral position. Upon meeting an obstruction, the vehicle moves laterally and substantially along the surface of the obstruction, up to a maximum of the width of the vehicle, the wheels straightening out either in response to the sensing rail again achieving the fully extended position or the vehicle having moved laterally the maximum amount corresponding to the width of the vehicle.

Claims

1. Automatically steered self-propelled vehicle for movement over the unobstructed portions of an area having obstructions, comprising a vehicle frame;

wheels mounted on said frame;

a sensing rail mounted on said frame and displaceable relative thereto between a normally extended position and a retracted position upon being urged against an obstruction by said vehicle;

drive means comprising a first reversible motor and connected to said wheels for rotating said wheels in a first and in a second direction opposite to the first direction to thereby impart a corresponding movement to said vehicle frame;

steering means comprising a second reversible motor connected to said wheels for displacing the same between a first position and a second position displaced through 90* from said first position;

control means connected to said first and second reversible motors for regulating operation of the same; and

switching means connected to said sensing rail and said second reversible motor for rotating said second reversible motor in one direction to cause said wheels to be displaced to said second position when said sensing rail reaches said retracted position, and said second reversible motor being rotatable in the other direction to cause said wheels to return to said first position when said sensing wheel reaches said extended position, said first reversible motor being rotatable in said first direction when said wheels are in said first position and said first reversible motor being rotatable in said second direction opposite to said first direction in response to regulation by said control means and to said wheel position, said first reversible motor being adapted to rotate in one of said directions in response to said wheels returning to said first position from said second position.

2. Automatically steered self-propelled vehicle as defined in claim 1, wherein said frame has a front end portion and said first direction corresponds to the forward direction of said vehicle relative to said front end portion, said wheels normally being in said first position for directing said vehicle in said forward direction.

3. Automatically steered self-propelled vehicle as defined in claim 2, wherein said sensing rail is mounted on said front end portion.

4. Automatically steered self-propelled vehicle as defined in claim 1, wherein said steering means comprises rack and pinion means connected to said wheels.

5. Automatically steered self-propelled vehicle as defined in claim 2, wherein said first reversible motor is adapted to rotate in said first direction in response to said wheels returning to said first position from said second position.

6. Automatically steered self-propelled vehicle as defined in claim 2, wherein said first reversible motor is adapted to rotate in the second direction in response to said wheels returning to said first position from said second position.

7. Automatically steered self-propelled vehicle as defined in claim 1, wherein said switching means comprises a switch having a large hysteresis, whereby said switch does not activate said control means until said sensing rail is in at least one of the fully extended and fully retracted states.

8. Automatically steered self-propelled vehicle as defined in claim 7, wherein electrical terminals are provided for application of a voltage to one of said Terminals for causing rotation of said second motor in a corresponding direction, said switch having a moving contact adapted to be connected to a source of voltage and operatively connected to said sensing rail for movement therewith, and two stationary contacts each connected to another of said terminals and engageable with said moving contact in response to movement of the latter, whereby the direction of said motor is a function of the position of said sensing rail.

9. Automatically steered self-propelled vehicle of a predetermined width for movement over the unobstructed surface of an area having obstructions, comprising a vehicle frame;

wheels mounted on said frame;

a sensing rail mounted on said frame and displaceable relative thereto between a normally extended position and a retracted position upon being urged against an obstruction by said vehicle;

drive means connected to said wheels for rotating the same to thereby impart motion to said vehicle frame;

steering means connected to said wheels for displacing the same between first and second positions in which said vehicle frame respectively moves in a first direction and a second direction inclined to said first direction;

control means connected to said steering means and to said drive means for regulating operation of these two latter means, said control means including a storage device for monitoring the distance travelled by said vehicle in said second direction with said sensing rail in said retracted position, said storage device being adapted to cause resumption of movement of said vehicle in said first direction when said vehicle is moved a distance corresponding to said predetermined width in said second direction independently of the position of said sensing rail; and

switching means connected to said sensing rail and said steering means for activating the latter in response to movement of said sensing rail to said retracted position upon engagement with an obstruction.