EP0028077A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Spindle rotation control system
Assignee: Fanuc Corp
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Filing: 1980-10-07
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Granted: —
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Expires: 2000-10-07
Abstract
Abstract The system controls the speed of a motor 2 which drives spindle 5. A speed detector 3 detects actual speed AV of motor 2. A speed control circuit 1 can control the motor so as to make actual speed AV coincide with a commanded speed CV. An orientation control circuit 4 provides a position deviation signal RPD on the basis of rotational spindle position and a commanded stopping position (STP). When signal RPD is applied to speed control circuit 1 in place of commanded speed CV (by means of changeover switch 10) the circuit 1 controls the motor so as to bring the spindle to rest at the commanded stopping position (STP). An in-position signal generating circuit 143 generates an in-position signal INPOS when the spindle reaches the vicinity of the commanded stopping position (STP). In response to the INPOS signal the gain of speed control circuit 1 (e.g., the gain of a phase compensation circuit 112) is increased to hold the spindle more rigidly in position.
Inventors
- 👤 Yoshinori Kohzai
- 👤 Yoshiki Fujioka
- 👤 Naoto Ota
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-29 08:05
CPC Classifications
G; G05; G05B; G05B19/00; G05B19/02; G05B19/18; G05B19/19; G05B19/39; G05B2219/00; G05B2219/30; G05B2219/41; G05B2219/41021; G05B2219/49; G05B2219/49273
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
102 words
A system for controlling the rotation of a spindle driven by a motor, comprising an orientation control circuit operable to produce a position deviation signal on the basis of rotational position of the spindle and a commanded stopping position, a motor control circuit operable on the basis of the position deviation signal to control rotation of the motor, and hence the spindle, to reduce the position deviation signal to zero, and wherein means are provided for raising the gain of the motor control circuit upon detecting that the rotational position of the spindle has reached the vicinity of the commanded stopping position.
Claim 2
Independent Claim
102 words
A system for controlling the rotation of a spindle driven by a motor, comprising an orientation control circuit operable to produce a position deviation signal on the basis of rotational position of the spindle and a commanded stopping position, a motor control circuit operable on the basis of the position deviation signal to control rotation of the motor, and hence the spindle, to reduce the position deviation signal to zero, and wherein means are provided for raising the gain of the motor control circuit upon detecting that the rotational position of the spindle has reached the vicinity of the commanded stopping position.
Claim 3
Dependent Claim
104 words
A system according to claim 1, further comprising speed detecting means for detecting the speed of the motor and for producing a signal indicative of the actual speed thereof; the motor control circuit being operable alternatively to receive a command speed signal and to control the motor so as to narrow to zero a deviation between the signal indicative of the actual speed thereof and the command speed signal; and there being changeover means for applying the position deviation signal produced by said orientation control circuit, in response to an orientation command signal, to the motor control circuit instead of the command speed signal..
Claim 4
Dependent Claim
118 words
The system according to claim 2, in which a position coder is mounted on said spindle for generating a one-revolution pulse whenever said spindle makes one revolution, and for generating N-number of position pulses for each revolution of said spindle, and in which said orientation control circuit includes a counter which is preset to the numerical' value N by the one-revolution pulse and whose content is counted down by each generated position pulse, a digital-to-analog converter for converting the content of said counter into an analog signal voltage, and a subtracting circuit for subtracting a fixed voltage value from the output voltage of said digital-to-analog convertor, the output of said subtracting circuit serving as the position deviation signal.
Claim 5
Dependent Claim
174 words
The system according to claim 2, in which a position coder is mounted on said spindle for generating a one-revolution pulse whenever said spindle makes one revolution, and for generating a plurality of position pulses for each revolution of said spindle, and in-which said orientation control circuit includes a stopping position setting circuit which is set to a numerical value N', a reversible counter which is set to a numerical value M corresponding to a predetermined angle when position pulses in accordance with the numerical value N' have been generated following the generation of the one-revolution pulse, the content of said reversible counter being counted up or counted down by each arriving position pulse in accordance with the direction of rotation of said spindle, and a digital-to-analog converter for converting the content of said reversible counter into an analog signal voltage, the stopping position of said spindle being changed by the numerical value N' set in said stopping position setting circuit, and the output of said digital-to-analog converter serving as the position deviation signal.
Claim 6
Independent Claim
14 words
The system according to claim4, in which said predetermined angle is set to 180°.
Claim 7
Dependent Claim
70 words
The system according to claim 2 , in which said changeover means includes a changeover switch provided on the input side of said motor control circuit, and a loop changeover circuit, said loop changeover circuit receiving an orientation command signal and responding by switching over said changeover switch to apply the position deviation signal to said motor control circuit when said spindle is at rest at the commanded stopping position.
Claim 8
Dependent Claim
105 words
The system according to claim 2 claim 3 or claim 4, in which said orientation control circuit includes a first circuit for detecting that the signal indicative of the average speed of the spindle has dropped below a fixed level, and a second circuit for detecting that the position deviation signal has fallen below a fixed level, said orien-. tation control circuit generating an in-position signal by taking the AND of a detection signal from said first circuit, a detection signal from said second circuit, and the orientation command signal, and applying said in-position signal to said motor control circuit to raise the gain thereof.
Claim 9
Dependent Claim
25 words
8 The system according to claim 6, in which said in-position signal is applied to a phase compensating circuit included in said motor control circuit.
References Cited (Backward Citations)
No citation records indexed.
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