Frequency responsive electrical circuit

Claim 1

A circuit responsive to the frequency of a train of trigger signals comprising monostable multivibrator means having a stable state, an unstable state and a natural timing period during which said multivibrator means remains in said unstable state after being triggered thereto from said stable state by a trigger signal, said monostable multivibrator including adjustable timing means for varying the length of said natural timing period whereby the length of time said multivibrator means is in said unstable state may be varied by adjusting said adjustable timing means, said timing means comprising a capacitor, charging circuit means for said capacitor, and discharging circuit means for said capacitor, one of said charging and discharging circuit means being infinitely variable wherein one of said charging and discharging circuits includes a normally open circuit element connected to receive and be closed by each of said trigger signals, such closure of said circuit element resulting in the charge on said capacitor changing sharply through said circuit element.

Claim 7

A system for controlling the speed of a moving member, comprising means for generating a train of input pulses having a frequency proportional to the speed of said member, monostable multivibrator means having a stable state, and unstable state, and a natural timing period, said monostable means being connected to receive said input pulses and generates an output pulse signal having a pulse width inversely proportional to the frequency of said train of input pulses, means for varying said natural timing period infinitely and thus infinitely varying said pulse width relative to said frequency, reversible actuator means including first and second energizing paths energizing said actuator means in one or the other of its two directions, said first and second paths being connected to receive said variable width output signals and energize said actuator means in one direction or the other depending upon said pulse width, said actuator being adapted to be connected to vary the speed of said moving member such that the frequency of said input pulses has a predetermined relation with said pulse width.

Claim 8

A system for controlling the speed of a moving member, comprising means for generating a train of input pulses having a frequency proportional to the speed of said member, monostable multivibrator means having a stable state, and unstable state, and a natural timing period, said monostable means being connected to receive said input pulses and generates an output pulse signal having a pulse width inversely proportional to the frequency of said train of input pulses, means for varying said natural timing period infinitely and thus infinitely varying said pulse width relative to said frequency, reversible actuator means including first and second energizing paths energizing said actuator means in one or the other of its two directions, said first and second paths being connected to receive said variable width output signals and energize said actuator means in one direction or the other depending upon said pulse width, said actuator being adapted to be connected to vary the speed of said moving member such that the frequency of said input pulses has a predetermined relation with said pulse width.

Claim 9

A system for controlling the speed of a moving member, comprising means for generating a train of input pulses having a frequency proportional to the speed of said member, monostable multivibrator means having a stable state, an unstable state, and a natural timing period, said monostable means being connected to receive said input pulses and generate an output pulse signal having a pulse width inversely proportional to the frequency of said train of input pulses, means for varying said natural timing period and thus vary said pulse width relative to said frequency, actuator means connected to receive said variable width output signals and be driven in a manner which is dependent upon said pulse width, said actuator being adapted to be connected to vary the speed of said moving member such that the frequency of said input pulses has a predetermined relation with said pulse width, and further including a negative feedback connection between said actuator and period varying means to improve the stability of said system.

Claim 10

A system for controlling the speed of a moving member, comprising means for generating a train of input pulses having a frequency proportional to the speed of said member, monostable multivibrator means having a stable state, an unstable state, and a natural timing period, said monostable means being connected to receive said input pulses and generate an output pulse signal having a pulse width inversely proportional to the frequency of said train of input pulses, means for varying said natural timing period and thus vary said pulse width relative to said frequency, actuator means connected to receive said variable width output signals and be driven in a manner which is dependent upon said pulse width, said actuator being adapted to be connected to vary the speed of said moving member such that the frequency of said input pulses has a predetermined relation with said pulse width, and further including a negative feedback connection between said actuator and period varying means to improve the stability of said system.

Claim 11

A system for controlling the speed of a moving member, comprising means for generating a train of input pulses having a frequency proportional to the speed of said member, monostable multivibrator means having a stable state, an unstable state, and a natural timing period, said monostable means being connected to receive said input pulses and generate an output pulse signal having a pulse width inversely proportional to the frequency of said train of input pulses, means for varying said natural timing period and thus vary said pulse width relative to said frequency, actuator means connected to receive said variable width output signals and be driven in a manner which is dependent upon said pulse width, said actuator being adapted to be connected to vary the speed of said moving member such that the frequency of said input pulses has a predetermined relation with said pulse width, said actuator comprising a bidirectional electric motor, and further including a motor control circuit connected to receive said variable width output signals and control energization of said motor for operation in one direction or the other depending upon the pulse width of said output signals.

Claim 12

A system for controlling the speed of a moving member, comprising means for generating a train of input pulses having a frequency proportional to the speed of said member, monostable multivibrator means having a stable state, an unstable state, and a natural timing period, said monostable means being connected to receive said input pulses and generate an output pulse signal having a pulse width inversely proportional to the frequency of said train of input pulses, means for varying said natural timing period and thus vary said pulse width relative to said frequency, actuator means connected to receive said variable width output signals and be driven in a manner which is dependent upon said pulse width, said actuator being adapted to be connected to vary the speed of said moving member such that the frequency of said input pulses has a predetermined relation with said pulse width, said actuator comprising a bidirectional electric motor, and further including a motor control circuit connected to receive said variable width output signals and control energization of said motor for operation in one direction or the other depending upon the pulse width of said output signals.