Bolt-on guidance system for lift truck
First Claim
1. An attachment for converting a self-powered vehicle of the type which is manually steered by an operator using a steering wheel connected to one end of a steering column into a manually operable vehicle which can also be selectively guided automatically to follow an external path, the attachment comprising:
- means mounted on the vehicle for sensing the external path and for generating an error signal representative of the deviation of the vehicle from the path,tachometer means connected to the steering wheel for generating a steering control signal proportional to the speed of manual rotation of the steering wheel,a steering actuator interposed between the steering wheel and the steering column for steering the vehicle by rotating the steering column in response to one of the signals, andmanually operable means mechanically connected to the steering wheel for enabling the vehicle operator, by shifting the position of the steering wheel with respect to the steering column, to selectively connect either the sensing means or the steering wheel tachometer means to the steering actuator to supply one of the signals thereto.
6 Assignments
0 Petitions
Accused Products
Abstract
An automatic guidance device for a self-powered cargo-moving vehicle is bolted directly over the steering column of the vehicle and is operated by a vehicle-borne sensor which follows a magnetic wire path, the guidance system having an automatic, sensor-directed mode, a manually operated power steering mode, and a manual override mode in which the guidance device is effectively disconnected and steering is undertaken by a direct mechanical linkage with the vehicle steering column.
35 Citations
11 Claims
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1. An attachment for converting a self-powered vehicle of the type which is manually steered by an operator using a steering wheel connected to one end of a steering column into a manually operable vehicle which can also be selectively guided automatically to follow an external path, the attachment comprising:
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means mounted on the vehicle for sensing the external path and for generating an error signal representative of the deviation of the vehicle from the path, tachometer means connected to the steering wheel for generating a steering control signal proportional to the speed of manual rotation of the steering wheel, a steering actuator interposed between the steering wheel and the steering column for steering the vehicle by rotating the steering column in response to one of the signals, and manually operable means mechanically connected to the steering wheel for enabling the vehicle operator, by shifting the position of the steering wheel with respect to the steering column, to selectively connect either the sensing means or the steering wheel tachometer means to the steering actuator to supply one of the signals thereto. - View Dependent Claims (2, 3)
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4. A guidance attachment for modifying a self-powered vehicle of the type having a steering control shaft which is manually operable at one end, into an automatically guided vehicle which, at the vehicle operator'"'"'s election, will automatically follow an externally defined course, the guidance attachment comprising:
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sensor means mounted on the vehicle for generating a sensor signal representative of both the lateral position of the vehicle with respect to the course and the direction of vehicle travel with respect to the course, steering motor means fitted over the manually operable end of the steering control shaft for moving the shaft to steer the vehicle, steering circuit means supplied with the sensor signal for generating a first steering control signal for the steering motor means to cause the steering motor means to automatically steer the vehicle along the external course, the steering circuit means including enabling logic means supplied with the sensor signal for producing an enabling output signal only when the vehicle is moving away from the external course after having come within a predetermined distance thereof under manual steering control, and switching means supplied with the enabling output signal to supply the first steering control signal to the motor means only after the enabling output signal is generated, whereby the vehicle will become automatically guided along the external course only after it has been manually steered within said predetermined distance. - View Dependent Claims (5, 6, 7, 8, 9)
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10. A guidance device for directing a self-powered vehicle along an externally defined course, the vehicle being of the type having at least one ground engaging steering wheel the guidance device comprising
vehicle mounted sensor means for sensing the position of the vehicle and its course with respect to the externally defined course and for producing an error signal representative of the deviation of the vehicle from the course, manually operable tachometer means, including a manually rotatable steering member, for generating a power steering control signal proportional to the speed of manual rotation of the steering member, an actuator supplied with one of the signals for rotating the ground engaging steering wheel to direct the course of the vehicle, and manually operable means to selectively connect either the sensor means or the tachometer means to the steering actuator to supply one of the signals thereto.
Specification