APPARATUS FOR CONTROLLING THE SPEED AND SPACING OF VEHICLES

• US 3,835,950 A
• Filed: 09/25/1972
• Issued: 09/17/1974
• Est. Priority Date: 09/23/1971
• Status: Expired due to Term

• Current Assignee: Hiroshi Takamiya, Tetsumasa Asano, Yoshinobu Morimoto
• Original Assignee: Hiroshi Takamiya, Tetsumasa Asano, Yoshinobu Morimoto
• Inventors: Asano, Tetsumasa, Takamiya, Hiroshi, Morimoto, Yoshinobu
• Primary Examiner(s): Reeves, Robert B.
• Assistant Examiner(s): Kocovsky, Thomas E.
• Application Number:
  US05/291,621
• Time in Patent Office: 722 Days
• Field of Search: 180/98 318/587 340/32,33 246/167D
• US Class Current: 180/167
• CPC Class Codes: B61L 3/18 using electric current passing between devices along the route and devices on the vehicle or train

Abstract

The fail-safe system for controlling separate vehicles running on a track, path or roadway permits both high vehicle speeds and high traffic densities. The system includes devices for measuring the speed of a lead vehicle and also the spacing between vehicles. A control system is provided which develops a control signal proportional to the square root of the sum of a signal proportional to the vehicle spacing and a signal proportional to the square of the lead vehicle speed. Alternatively, the control system may provide a control signal proportional to the sum of signals proportional to the lead vehicle speed and to the square root of the vehicle spacing. These control signals are used to regulate the speed and following distance of vehicles behind the lead vehicle. Various other alternative embodiments of the invention are disclosed, as are several novel features such as an emergency braking system.

Claims

1. An apparatus for controlling a vehicle comprising:

distance measuring means for measuring the distance between a lead vehicle and a following vehicle and for generating a signal proportional to said distance;

speed measuring means for measuring the speed of said lead vehicle and for generating a signal proportional to said speed;

circuit means for producing an output signal means for providing an output signal proportional to the square root of the sum of said signal proportional to said distance and the square of said signal proportional to said speed; and

, control means for controlling said vehicle in response to said output signal from said circuit means wherein said speed measuring means comprises;

a moving element coupled to said vehicle;

a plurality of ground elements spaced a predetermined distance apart for generating vehicle passing signals as said moving element passes each of said ground elements;

oscillator means for generating a periodic output signal having a period shorter than that of said vehicle passing signals;

counting means for repeatedly counting said oscillator output during the presence of said vehicle passing signal; and

memory means for storing the maximum counts accumulated in said counting means.

2. An apparatus for controlling a vehicle as in claim 1, wherein said speed measuring means comprises:

a moving element coupled to said vehicle;

a plurality of spaced ground elements for generating vehicle passing signals as said moving element passes each of said ground elements;

counting means for counting said vehicle passing signals; and

, limiting means for limiting the counting interval of said counting means.

3. An apparatus for controlling a vehicle comprising:

distance measuring means for measuring the distance between a lead vehicle and a following vehicle and for generating a signal proportional to said distance;

speed measuring means for measuring the speed of said lead vehicle and for generating a signal proportional to said speed;

circuit means for providing a signal proportional to the square root of said signal proportional to said distance; and

further providing a signal proportional to the sum of said signal proportional to said speed and said signal proportional to said square root;

control means for controlling said vehicle in response to said output signal from said circuit means;

wherein said speed measuring means comprises a moving element coupled to said vehicle;

a plurality of ground elements spaced a predetermined distance apart for generating vehicle passing signals as said moving element passes each of said ground elements;

oscillator means for generating a periodic output signal having a period shorter than that of said vehicle passing signal;

counting means for repeatedly counting said oscillator output during the presence of said vehicle passing signal; and

memory means for storing the maximum counts accumulated in said counting means.

4. An apparatus for controlling a vehicle as in claim 3, wherein said speed measuring means comprises:

a moving element coupled to said vehicle;

a plurality of ground elements placed specific distances apart for generating vehicle passing signals as said moving element passes each of said ground elements;

counting means for counting said vehicle passing signals; and

, limiting means for limiting the counting interval of said counting means.

5. A system for controlling vehicles comprising:

speed measuring means for measuring the speed of a vehicle and for generating a signal proportional to said speed;

distance measuring means for measuring the separation between said vehicle and a lead vehicle and for generating a signal proportional to said separation;

operator means for generating a control signal in response to said signals proportional to said speed and said separation;

a reference voltage source;

adding circuit means coupled to said reference voltage source for developing an output signal proportional to an integral multiple of said reference voltage;

a plurality of individually insulative conductive segments carrying a signal for controlling said vehicle;

receiver means carried by said vehicle for detecting said signal carried by said conductive segments;

means coupled to said vehicle for generating a signal which is proportional to the square of said vehicle speed; and

transmitting means for transmitting said signal proportional to the square of said vehicle speed to said conductive segments.

6. A system for controlling vehicles as in claim 5, further comprising:

a plurality of spaced ground elements for detecting the passage of vehicles;

a plurality of counters associated with said plurality of ground elements for counting the outputs thereof;

a plurality of series connected gate circuit means controlled by the outputs of said ground elements;

vehicle speed setting circuit means for setting the speed of said vehicle corresponding to the outputs of said counters; and

, means for transmitting the output of said vehicle speed setting circuit means to said vehicle.

7. A system for controlling vehicles as in claim 5, further comprising:

a fixed, ground mounted structure;

emergency braking means coupled to said vehicle, said emergency braking means acting directly between said vehicle and said fixed, ground mounted structure; and

, brake control means for controlling the actuation of said emergency braking means, said brake control means including means for differentiating said signal proportional to said separation, and means for comparing said differentiated signal with said signal proportional to said speed.

8. A system for controlling vehicles as in claim 5, wherein:

said means for generating a signal which is proportional to the square of said vehicle speed comprises a motor, and said speed measuring means provides the field input power for said motor.

9. A system for controlling vehicles as in claim 5, further comprising:

limiting means for limiting the output of said operator means, whereby the speed of said vehicle is limited to a preset maximum value.

10. A system for controlling vehicles as in claim 5, wherein:

said operator means comprises a plurality of control devices for controlling a plurality of vehicles; and

further comprising communication means for communicating speed regulating signals among said vehicles.

11. A system for controlling vehicles as in claim 5, wherein:

said speed measuring means includes differentiating means for detecting and for generating an output signal proportional to changes in said signal proportional to said separation.

12. A system for controlling vehicles aS in claim 11, further comprising:

a reference voltage source;

adding circuit means coupled to said source for developing an output signal proportional to an integral multiple of said reference voltage;

a plurality of conductive segments, each insulated from the others, and arranged along a prescribed path; and

wherein said operator means generates said control signal in response to said output signals of said differentiating means and said adding circuit means, and said control signal is applied to said conductive segments.