Patent US4964140A successfully refreshed from Google Patents.
US4964140A
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Digital differential signal transmission apparatus
Assignee: Fanuc Corp
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Filing: 1988-07-08
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Granted: 1990-10-16
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Expires: 2008-07-08
Abstract
Abstract A digital differential signal transmission apparatus is provided in a transmission line connecting a device (3) requiring an explosion-proof structure with a differential driver (101) or differential receiver (102). A shunt diode-type safety device (16) is inserted in order to realize an essential safe explosion-proof structure. High impedance transmission lines, which transmit and receive a single end signal, are employed as the transmission lines. Another shunt diode-type safety device (408) is inserted in a power supply line (143) connected to transmitting equipment (405, 406) on the side of the abovementioned device.
Inventors
- 👤 Mikio Yonekura
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 12:19
CPC Classifications
H; H04; H04L; H04L25/00; H04L25/02; H04L25/0264; H04L25/028; H04L25/0272; H04L25/0292
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
123 words
A digital differential signal transmission apparatus provided in a transmission line for transmitting a differential signal to and receiving a differential signal from a device requiring an explosion-proof structure, a shunt diode-type safety device being inserted to provide the transmission line with an essential safe explosion-proof structure, the apparatus comprising: a receiver, operatively connected to receive the digital differential signal, for converting the digital differential signal into a single end input; a driver for re-converting said single end input into a differential signal and outputting a signal; high-input impedance receiver, operatively connected between said receiver and said driver; and shunt diode-type safety devices, inserted in a power supply line and operatively connected in series with said high-input impedance receiver, having an explosion-proof structure.
Claim 2
Dependent Claim
123 words
A digital differential signal transmission apparatus provided in a transmission line for transmitting a differential signal to and receiving a differential signal from a device requiring an explosion-proof structure, a shunt diode-type safety device being inserted to provide the transmission line with an essential safe explosion-proof structure, the apparatus comprising: a receiver, operatively connected to receive the digital differential signal, for converting the digital differential signal into a single end input; a driver for re-converting said single end input into a differential signal and outputting a signal; high-input impedance receiver, operatively connected between said receiver and said driver; and shunt diode-type safety devices, inserted in a power supply line and operatively connected in series with said high-input impedance receiver, having an explosion-proof structure.
Claim 3
Dependent Claim
42 words
A digital differential signal transmission apparatus according to claim 1, wherein said shunt diode-type safety device comprises: a voltage-limiting Zener diode; a current-limiting resistor connected to said Zener diode; and a fuse, connected to said Zener diode, for protecting said Zener diode.
Claim 4
Dependent Claim
37 words
A digital differential signal transmission apparatus according to claim 1, further comprising a regulator, inserted in the power supply line and operatively connected to said receiver and said driver, for regulating voltage to a predetermined voltage value.
Claim 5
Dependent Claim
56 words
A digital differential signal transmission apparatus according to claim 1, wherein the transmission line for transmitting and receiving the digital differential signal is a two-way transmission line having four lines, and wherein said high-input impedance receivers are inserted in series with respect to the transmission lines on the side of the device requiring said explosion-proof structure.
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) | 1993-10-15 | 1994-04-16 | 1994-10-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-10-15 | 1998-04-16 | 1998-10-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-10-15 | 2002-04-16 | 2002-10-16 | $7700.00 | Window Closed / Lapsed |