US4574343A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Contactless press control device
Assignee: KOMATSU SEISAKUSHO A CORP OF JAPAN KK
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Filing: 1982-09-29
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Granted: 1986-03-04
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Expires: 2002-09-29
Abstract
Abstract A contactless control device for a press having a device for checking whether an abnormality detector normally operates or not. The device of this invention is constructed to operate when power is fed to the press or when the press is stopped at its top dead center. A self-check operation generates and applies a dummy pulse to the abnormality detector. The abnormality detector generates an error signal corresponding to the dummy signal if normal. Since no error signal is generated when the abnormality detector is abnormal, the press is not operated. Operation of the press is dependent on the error signal. Whether the abnormality detector is normal or not is indicated during a self-check operation.
Inventors
- 👤 Takao Inatomi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 08:41
CPC Classifications
G; G05; G05B; G05B19/00; G05B19/02; G05B19/04; G05B19/048
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
151 words
A contactless control device for a press having a controller for controlling the operation of the press and an abnormality detector for detecting the abnormality of the operation of said controller, a detection of such abnormality preventing press operation, comprising: means for generating dummy fault signals before said press is started and applying the signals to said abnormality detector, and means for detecting as a fault the state when no fault detection signal is generated from said abnormality detector upon application of each dummy fault signal, such fault detection preventing press operation, and wherein said dummy fault signals correspond to items to be checked, and an initial dummy fault signal is generated when power is fed to said press or when said press is stopped at its top dead center, and the next dummy fault signal is generated only when an abnormality is not detected for each item to be checked.
Claim 2
Dependent Claim
151 words
A contactless control device for a press having a controller for controlling the operation of the press and an abnormality detector for detecting the abnormality of the operation of said controller, a detection of such abnormality preventing press operation, comprising: means for generating dummy fault signals before said press is started and applying the signals to said abnormality detector, and means for detecting as a fault the state when no fault detection signal is generated from said abnormality detector upon application of each dummy fault signal, such fault detection preventing press operation, and wherein said dummy fault signals correspond to items to be checked, and an initial dummy fault signal is generated when power is fed to said press or when said press is stopped at its top dead center, and the next dummy fault signal is generated only when an abnormality is not detected for each item to be checked.
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) | 1989-03-03 | 1989-09-02 | 1990-03-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-03-03 | 1993-09-02 | 1994-03-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-03-03 | 1997-09-02 | 1998-03-04 | $7700.00 | Window Closed / Lapsed |