Precision motion control device or the like

Claim 2

A paper advance mechanism for a high speed printer, comprising a servo means for moving the printer paper, a sprocket generator coupled to said servo means adapted to generate a multiplicity of sprocket pulSes for each line of paper advance, a counter for storing a count which is a predetermined multiple of the lines of paper advance, a register means coupled to said counter for receiving the count stored in said counter, a digital-to-analog converter coupled to said register means for developing an error voltage dependent on the count stored in the register means and for applying said error voltage to said servo means to cause said servo to advance paper, an adder network having two inputs thereto and a summing output, one of said adder inputs being connected to the output of said register means, an input means connected to the other adder input for applying a count signal indicative of the number of lines of paper advance that is to be executed, the summing output of said adder being connected to the input to said counter to load said counter with a count at the start of a paper advance operation, and means utilizing the output of said sprocket pulse generator to decrement said counter as paper is advanced.

Claim 3

The system of claim 1 wherein said input means comprises a lines-to-go register that stores a signal indicative of the number of lines it is desired to advance paper and a multiplier that multiplies the number stored in said lines-to-go register by said predetermined multiple.

Claim 4

The system of claim 2 wherein there is included means for changing said predetermined multiple.

Claim 5

The system of claim 1 wherein said digital-to-analog converter generates an error voltage whose magnitude varies as a square root function of the count remaining in said register means.

Claim 6

The system of claim 4 wherein said input means comprises a lines-to-go register that stores a signal indicative of the number of lines it is desired to advance paper and a multiplier that multiplies the number stored in said lines-to-go register by said predetermined multiple.

Claim 7

The system of claim 5 wherein there is included means for changing said predetermined multiple.

Claim 8

The system of claim 1 wherein the last-named means includes a further means for manually incrementing or decrementing the count held in said counter.

Claim 9

A drive system for positioning a movable member to any of a plurality of discrete stop positions, comprising: a servo mechanism for moving said movable member, a sprocket pulse generator coupled to said servo mechanism, said sprocket generator being operative to produce a series of sprocket pulses as the movable member is moved by said servo mechanism from one stop position to another, a counter, a digital register for storing the count held in said counter, a digital-to-analog converter coupled to the output of said register for developing a signal voltage indicative of the count stored in said register, means utilizing the signal voltage from said digital-to-analog converter to actuate said servo mechanism, a signal input means for delivering a digital signal indicative of the number of stop positions through which said movable member is to be moved, an adder network having two inputs thereto and a summing output, one of said adder inputs being connected to said signal input means, the other of said adder inputs being connected to the output of said register, the summing output of said adder being connected to said counter to load said counter with a count which is equal to the count signal supplied by said signal input means plus the count stored in said register, and means utilizing the output of said sprocket pulse generator to decrement said counter.

Claim 10

A drive system for positioning a movable member to any of a plurality of discrete stop positions, comprising: a servo mechanism for moving said movable member, a sprocket pulse generator coupled to said servo mechanism, said sprocket generator being operative to produce a series of sprocket pulses as the movable member is moved by said servo mechanism from one stop position to another, a counter, a digital register for storing the count held in said counter, a digital-to-analog converter coupled to the output of said register for developing a signal voltage indicative of the count stored in said register, means utilizing the signal voltage from said digital-to-analog converter to actuate said servo mechanism, a signal input means for delivering a digital signal indicative of the number of stop positions through which said movable member is to be moved, an adder network having two inputs thereto and a summing output, one of said adder inputs being connected to said signal input means, the other of said adder inputs being connected to the output of said register, the summing output of said adder being connected to said counter to load said counter with a count which is equal to the count signal supplied by said signal input means plus the count stored in said register, and means utilizing the output of said sprocket pulse generator to decrement said counter.

Claim 11

A drive system for positioning a movable member to any of a plurality of discrete stop positions, comprising; a servo means coupled to said member for moving the same to any of said stop positions, said servo means having acceleration and brake inputs for controlling the operation thereof, a sprocket pulse generator coupled to said servo means for generating sprocket pulses as said member is moved from one stop position to the next, a storage means for storing a digital count indicative of the number of stop pOsitions through which the movable member is to be moved, a digital-to-analog converter connected to said storage means for generating a reference voltage whose amplitude varies in accordance with the digital count held by said storage means after said count drops below a predetermined value, means utilizing the sprocket pulses generated by said sprocket pulse generator for decrementing the digital count held in said storage means as said member is moved toward its desired stop position, a voltage generating means coupled to said servo means for generating a voltage whose amplitude varies as a function of the velocity of said member, a voltage comparator coupled to receive the output from said voltage generator and said digital-to-analog converter and to generate an error signal in accordance with the difference between said voltages, signal switching means, including a first signal path for coupling the error voltage to the acceleration input of said servo means whenever the output of said voltage generator drops below the digital-to-analog reference voltage and a second signal path for coupling the error voltage to the brake input of said servo means whenever the output voltage from said voltage generator rises above the reference voltage output of the digital-to-analog converter, and means rendering the second signal path operative only when the digital count stored in said storage means drops below said predetermined value.

Claim 12

A drive system for positioning a movable member to any of a plurality of discrete stop positions, comprising; a servo means coupled to said member for moving the same to any of said stop positions, said servo means having acceleration and brake inputs for controlling the operation thereof, a sprocket pulse generator coupled to said servo means for generating sprocket pulses as said member is moved from one stop position to the next, a storage means for storing a digital count indicative of the number of stop pOsitions through which the movable member is to be moved, a digital-to-analog converter connected to said storage means for generating a reference voltage whose amplitude varies in accordance with the digital count held by said storage means after said count drops below a predetermined value, means utilizing the sprocket pulses generated by said sprocket pulse generator for decrementing the digital count held in said storage means as said member is moved toward its desired stop position, a voltage generating means coupled to said servo means for generating a voltage whose amplitude varies as a function of the velocity of said member, a voltage comparator coupled to receive the output from said voltage generator and said digital-to-analog converter and to generate an error signal in accordance with the difference between said voltages, signal switching means, including a first signal path for coupling the error voltage to the acceleration input of said servo means whenever the output of said voltage generator drops below the digital-to-analog reference voltage and a second signal path for coupling the error voltage to the brake input of said servo means whenever the output voltage from said voltage generator rises above the reference voltage output of the digital-to-analog converter, and means rendering the second signal path operative only when the digital count stored in said storage means drops below said predetermined value.