US4524313A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Error detecting mechanism for servosystem
Assignee: Toyota Central R&D Labs Inc
•
Filing: 1983-02-03
•
Granted: 1985-06-18
•
Expires: 2003-02-03
Abstract
Abstract The invention relates to a mechanism wherein a relative rotary angle of a driving motor is detected by use of an encoder, and, if an error occurs in a servo control action when the driving motor is servo-controlled in accordance with a deviation value of the relative rotary angle from a desired rotary angle of the driving motor, then the servo control action is brought to an emergency stop. A potentiometer for detecting an absolute rotary angle of the driving motor is connected to a rotary shaft of the driving motor and said emergency stop is effected when a difference between said absolute rotary angle and said relative rotary angle exceeds a preset tolerance value, so that an error in the servo control action can be reliably prevented.
Inventors
- 👤 Toshitaka Kuno
- 👤 Hiroshi Moribe
- 👤 Atsushi Kamiya
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 22:19
CPC Classifications
G; G05; G05B; G05B19/00; G05B19/02; G05B19/18; G05B19/19; G05B19/21; G05B19/23; G05B19/231; G05B2219/00; G05B2219/30; G05B2219/42; G05B2219/42318
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
144 words
An error detecting mechanism for a servosystem, comprising: a rotary angle detecting system including an encoder connected to a rotary shaft of a driving motor, for detecting a relative rotary angle of said driving motor and a potentiometer for detecting an absolute rotary angle of said driving motor; a driving-controlling system for driving and controlling said driving motor in accordance with a deviation value of a rotary angle detection value of said driving motor from a desired rotary angle; and an error preventing system for preventing a malfunction of said driving-controlling system; said error preventing system being provided with an emergency stop control circuit for effecting an emergency stop of said driving motor when a deviation value between said relative rotary angle detection value detected by said encoder and said absolute rotary angle detection value detected by said potentiometer exceeds a preset tolerance value.
Claim 2
Dependent Claim
144 words
An error detecting mechanism for a servosystem, comprising: a rotary angle detecting system including an encoder connected to a rotary shaft of a driving motor, for detecting a relative rotary angle of said driving motor and a potentiometer for detecting an absolute rotary angle of said driving motor; a driving-controlling system for driving and controlling said driving motor in accordance with a deviation value of a rotary angle detection value of said driving motor from a desired rotary angle; and an error preventing system for preventing a malfunction of said driving-controlling system; said error preventing system being provided with an emergency stop control circuit for effecting an emergency stop of said driving motor when a deviation value between said relative rotary angle detection value detected by said encoder and said absolute rotary angle detection value detected by said potentiometer exceeds a preset tolerance value.
Claim 3
Dependent Claim
20 words
An error detecting mechanism for a servosystem as set forth in claim 1, wherein said encoder is a rotary encoder.
Claim 4
Dependent Claim
38 words
An error detecting mechanism for a servosystem as set forth in claim 2, wherein said rotary encoder and said potentiometer are connected through a reduction gear to a shaft opposite to the drive shaft of said driving motor.
Claim 5
Dependent Claim
21 words
An error detecting mechanism for a servosystem as set forth in claim 3, wherein said driving motor is a DC motor.
Claim 6
Dependent Claim
34 words
An error detectting mechanism for a servosystem as set forth in claim 4, wherein said DC motor is provided at a joint portion of an arm of the industrial robot, for driving said arm.
Claim 7
Dependent Claim
30 words
An error detecting mechanism for a servosystem as set forth in claim 5, wherein said DC motor, rotary encoder and potentiometer are housed in one and the same motor unit.
Claim 8
Dependent Claim
44 words
An error detecting mechanism for a servosystem as set forth in claim 6, wherein said rotary angle detecting system includes a counter adapted to be reset when the industrial robot is started in operation, and thereafter, to count pulses outputted from said rotary encoder.
Claim 9
Dependent Claim
37 words
An error detecting mechanism for a servosystem as set forth in claim 7, wherein said rotary angle detecting system includes an A/D converter for converting an analogue detection value outputted from said potentiometer into a digital signal.
Claim 10
Dependent Claim
46 words
An error detecting mechanism for a servosystem as ser forth in claim 8, wherein said error preventing system includes a comparator for digitally comparing the relative rotary angle detection value outputted from said counter with the absolute rotary angle detection value outputted from said A/D converter.
Claim 11
Dependent Claim
48 words
An error detecting mechanism for a servosystem as set forth in claim 9, wherein said error preventing system includes an emergency stop control circuit for outputting an emergency stop command signal to said DC motor when a deviation value outputted from said comparator exceeds the preset tolerance value.
Claim 12
Dependent Claim
54 words
An error detecting mechanism for a servosystem as set forth in claim 10, wherein said error preventing system includes a brake for braking said DC motor and a contact for being `ON` operated in response to a command signal outputted from said emergency stop control circuit to supply a driving current to said brake.
Claim 13
Dependent Claim
103 words
An error detecting mechanism for a servosystem as set forth in claim 11, wherein said driving-controlling system includes a rotary angle commanding circuit for commanding a rotary angle of said DC motor, a comparator for comparing the relative rotary angle detection value from said counter with the desired rotary angle from said rotary angle commanding circuit, an D/A converter for converting a deviation value of the relative rotary angle detection value from the desired rotary angle outputted from said comparator into an analogue signal and a driver for driving said DC motor in accordance with the deviation value converted into an analogue signal.
Claim 14
Dependent Claim
47 words
An error detecting mechanism for a servosystem as set forth in claim 12, wherein said error preventing system includes a contact for being `OFF` operated in response to a command signal outputted from said emergency stop control circuit to cut off the current supplied to said driver.
Claim 15
Dependent Claim
191 words
An error detecting mechanism for a servosystem, comprising: a rotary angle detecting system including a rotary encoder connected to a rotary shaft of a DC motor for driving an arm of a industrial robot for detecting a relative rotary angle of said DC motor and a potentiometer for detecting an absolute rotary angle of said DC motor, said rotary encoder and said potentiometer being connected through a reduction gear to a shaft opposite to the drive shaft of said DC motor; a driving-controlling system for driving and controlling said DC motor in accordance with a deviation value of a rotary angle detection value of said DC motor from a desired rotary angle; and an error preventing system for preventing a malfunction of said driving-controlling system, said DC motor, said rotary encoder and said potentiometer being housed in one end of the same motor unit, said rotary angle detecting system including a counter adapted to be reset when the industrial robot is started in operation to count pulses outputted from said rotary encoder, and includes an A/D converter for connecting an analogue detection value outputted from said potentiometer into a digital signal.
Claim 16
Dependent Claim
191 words
An error detecting mechanism for a servosystem, comprising: a rotary angle detecting system including a rotary encoder connected to a rotary shaft of a DC motor for driving an arm of a industrial robot for detecting a relative rotary angle of said DC motor and a potentiometer for detecting an absolute rotary angle of said DC motor, said rotary encoder and said potentiometer being connected through a reduction gear to a shaft opposite to the drive shaft of said DC motor; a driving-controlling system for driving and controlling said DC motor in accordance with a deviation value of a rotary angle detection value of said DC motor from a desired rotary angle; and an error preventing system for preventing a malfunction of said driving-controlling system, said DC motor, said rotary encoder and said potentiometer being housed in one end of the same motor unit, said rotary angle detecting system including a counter adapted to be reset when the industrial robot is started in operation to count pulses outputted from said rotary encoder, and includes an A/D converter for connecting an analogue detection value outputted from said potentiometer into a digital signal.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-06-17 | 1988-12-17 | 1989-06-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-06-17 | 1992-12-17 | 1993-06-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-06-17 | 1996-12-17 | 1997-06-18 | $7700.00 | Window Closed / Lapsed |