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US4099704A Expired / Lapsed US ⏱️ 0.0 years remaining

Vacuum valve apparatus

Assignee: Hitachi Ltd
•
Filing: 1976-12-20
•
Granted: 1978-07-11
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Expires: 1996-12-20
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Abstract

Abstract Disclosed is a vacuum valve apparatus comprising a valve head, a motor for driving the valve head, means for checking the position of the valve adapted to issue a first signal upon detecting that the valve head is moved to be within a predetermined valve-closed range, means for checking electric current adapted to issue a second signal when the driving current for the motor is increased to a predetermined value, switching means adapted to cut the driving current supply to the motor upon detecting said second signal, and means for issueing a third signal for confirming the complete closure of the valve when both of the first and the second signals are simultaneously obtained.

Inventors

  • 👤 Masahide Okumura
  • 👤 Yoshio Sakitani
  • 👤 Yasushi Nakaisumi
  • 👤 Toshiaki Nakata

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-27 12:19
CPC Classifications
F; F16; F16K; F16K37/00; F16K51/00; F16K51/02

Claims Analysis

Total Claims: 11
Claim 1
Independent Claim 105 words
A vacuum valve apparatus comprising a valve head, a motor for driving said valve head, and means for confirming complete closure of said valve head, said means for confirming comprising first signal generating means for detecting the position of said valve head and generating a first signal when said valve head is situated within a predetermined valve-closed range, second signal generating means for detecting the driving current of said motor and generating a second signal when said driving current has reached a predetermined level, and third signal generating means for generating a third signal only when both of said first and second signals are generated.
Claim 2
Dependent Claim 105 words
A vacuum valve apparatus comprising a valve head, a motor for driving said valve head, and means for confirming complete closure of said valve head, said means for confirming comprising first signal generating means for detecting the position of said valve head and generating a first signal when said valve head is situated within a predetermined valve-closed range, second signal generating means for detecting the driving current of said motor and generating a second signal when said driving current has reached a predetermined level, and third signal generating means for generating a third signal only when both of said first and second signals are generated.
Claim 3
Dependent Claim 26 words
A vacuum valve apparatus as claimed in claim 1, comprising switching means for cutting the power supply to said motor in response to said second signal.
Claim 4
Dependent Claim 34 words
A vacuum valve apparatus as claimed in claim 1, wherein said third signal generating means is operable to generate said third signal only when both of said first and second signals are simultaneously generated.
Claim 5
Dependent Claim 28 words
A vacuum valve apparatus as claimed in claim 3, further comprising a switching means for cutting the power supply to said motor in response to said second signal.
Claim 6
Dependent Claim 28 words
A vacuum valve apparatus according to claim 1, wherein said third signal generating means comprises an AND circuit operatively associated with said first and second signal generating means.
Claim 7
Dependent Claim 28 words
A vacuum valve apparatus according to claim 2, wherein said third signal generating means comprises an AND circuit operatively associated with said first and second signal generating means.
Claim 8
Dependent Claim 24 words
A vacuum valve apparatus according to claim 1, wherein said first signal generating means comprises a light source means and a light detector means.
Claim 9
Dependent Claim 34 words
A vacuum valve apparatus according to claim 7, wherein said light source means interacts with said light detector means through said valve head when said valve head is situated within said predetermined valve-closed range.
Claim 10
Dependent Claim 24 words
A vacuum valve apparatus according to claim 5, wherein said first signal generating means comprises a light source means and a light detector means.
Claim 11
Dependent Claim 34 words
A vacuum valve apparatus according to claim 9, wherein said light source means interacts with said light detector means through said valve head when said valve head is situated within said predetermined valve-closed range.

References Cited (Backward Citations)

US916831A Cited
US2600549A Cited
US3341760A Cited
US4001661A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1981-07-10 1982-01-09 1982-07-11 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1985-07-10 1986-01-09 1986-07-11 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1989-07-10 1990-01-09 1990-07-11 $7700.00 Window Closed / Lapsed

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