Patent US4338013A successfully refreshed from Google Patents.
US4338013A
Expired / Lapsed
US
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Electromagnetically driven shutter
Assignee: Canon Inc
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Filing: 1981-01-05
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Granted: 1982-07-06
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Expires: 2001-01-05
Abstract
Abstract In the disclosed shutter, shutter blades are reciprocatable between exposure start positions and end positions. Reciprocative rotating electromagnetic drive sources with stators and rotors reciprocate the shutter blades. Magnetic members on the stator facing the rotors hold the latter at positions corresponding to the blades' start positions and are movable to vary the gaps formed between the rotors and themselves.
Inventors
- 👤 Fumio Shimada
- 👤 Nobuaki Date
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 16:34
CPC Classifications
G; G03; G03B; G03B9/00; G03B9/08; G03B9/10; G03B9/18; H; H02; H02K; H02K33/00; H02K33/16
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
104 words
An electromagnetically driven shutter, comprising: shutter blades capable of reciprocative movements between positions to start running for an exposure and positions to complete running; electromagnetic driving sources of a reciprocative rotating type for actuating the shutter blades, said driving sources having stators and rotors coupled with the shutter blades; and magnetic members positioned on the stators to face positions of the rotors corresponding to the positions of the shutter blades to start running for holding the rotors at said positions with the attracting power between the rotors and the magnetic members, said magnetic members being operable for regulating gaps between themselves and the rotors.
Claim 2
Dependent Claim
104 words
An electromagnetically driven shutter, comprising: shutter blades capable of reciprocative movements between positions to start running for an exposure and positions to complete running; electromagnetic driving sources of a reciprocative rotating type for actuating the shutter blades, said driving sources having stators and rotors coupled with the shutter blades; and magnetic members positioned on the stators to face positions of the rotors corresponding to the positions of the shutter blades to start running for holding the rotors at said positions with the attracting power between the rotors and the magnetic members, said magnetic members being operable for regulating gaps between themselves and the rotors.
Claim 3
Dependent Claim
132 words
An electromagnetically drive shutter, comprising: leading shutter blades and follower shutter blades capable of respective reciprocative movements between positions to start running for an exposure and positions to complete the running; electromagnetic driving sources of a reciprocative rotating type for respectively actuating said leading and follower shutter blades, said driving sources having rotors made of permanent magnets being coupled with the shutter blades and stators comprising filed coils and yokes; and magnetic members protruding into the stators and facing positions of the rotors corresponding to the positions of the shutter blades to start running, said magnetic members being arranged to be able to regulate the gaps between themselves and the rotors and holding the shutter blades at their positions to start running by the attracting power operating between themselves and the rotors.
Claim 4
Dependent Claim
132 words
An electromagnetically drive shutter, comprising: leading shutter blades and follower shutter blades capable of respective reciprocative movements between positions to start running for an exposure and positions to complete the running; electromagnetic driving sources of a reciprocative rotating type for respectively actuating said leading and follower shutter blades, said driving sources having rotors made of permanent magnets being coupled with the shutter blades and stators comprising filed coils and yokes; and magnetic members protruding into the stators and facing positions of the rotors corresponding to the positions of the shutter blades to start running, said magnetic members being arranged to be able to regulate the gaps between themselves and the rotors and holding the shutter blades at their positions to start running by the attracting power operating between themselves and the rotors.
Claim 5
Dependent Claim
31 words
An electromagnetically driven shutter according to claim 2, wherein the magnetic members are formed as screws threaded into the yokes and can be adjusted from outside of the electromagnetic driving source.
Claim 6
Dependent Claim
53 words
An electromagnetically driven shutter according to claim 2, in which the shutter has means to control the positions of the rotors corresponding to the positions of the shutter blades to start running, and the magnetic members are provided outside of rotating ranges of the rotors corresponding to operating ranges of the shutter blades.
Claim 7
Dependent Claim
136 words
An electromagnetically drive shutter, comprising: leading shutter blades and follower blades which can make respective reciprocative movements between their positions to start running for an exposure and their positions to complete the running; electromagnetic driving sources of a reciprocative rotating type to respectively actuate the leading and follower shutter blades, said driving sources having rotors including movable coils which have magnetic pieces attached thereto and are coupled with the shutter blades, and stators comprising permanent magnets and yokes; and magnetic members located so that their positions can be regulated at the stators, facing positions of the rotors corresponding to the positions of the shutter blades to start running, said magnetic members holding the shutter blades at their positions to start running by attracting power operating between the magnetic members and the magnetic pieces of the rotors.
Claim 8
Dependent Claim
136 words
An electromagnetically drive shutter, comprising: leading shutter blades and follower blades which can make respective reciprocative movements between their positions to start running for an exposure and their positions to complete the running; electromagnetic driving sources of a reciprocative rotating type to respectively actuate the leading and follower shutter blades, said driving sources having rotors including movable coils which have magnetic pieces attached thereto and are coupled with the shutter blades, and stators comprising permanent magnets and yokes; and magnetic members located so that their positions can be regulated at the stators, facing positions of the rotors corresponding to the positions of the shutter blades to start running, said magnetic members holding the shutter blades at their positions to start running by attracting power operating between the magnetic members and the magnetic pieces of the rotors.
Claim 9
Dependent Claim
54 words
An electromagnetically driven shutter according to claim 5, wherein the shutter includes means to control the positions of the rotors corresponding to the positions of the shutter blades to start running, and the magnetic members are positioned outside of the rotating range of the rotors corresponding to the operating range of the shutter blades.
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) | 1985-07-05 | 1986-01-04 | 1986-07-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-07-05 | 1990-01-04 | 1990-07-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-07-05 | 1994-01-04 | 1994-07-06 | $7700.00 | Window Closed / Lapsed |