US3744393A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Preset stop device for interchangeable lens for single lens reflex camera
Assignee: Canon Inc
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Filing: 1971-12-20
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Granted: 1973-07-10
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Expires: 1991-12-20
Abstract
Abstract A preset stop or aperture device in an interchangeable lens for a single-lens reflex camera comprises an aperture ring for stopping down aperture blades to a position determined by a preset ring. The aperture ring is driven by an electromagnetic drive means connected with a power supply circuit including a switch actuated by the aperture driving member of the camera.
Inventors
- 👤 T Uchiyama
- 👤 T Taguchi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 07:53
CPC Classifications
G; G03; G03B; G03B19/00; G03B19/02; G03B19/12; G03B9/00; G03B9/02; G03B9/07
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
176 words
A preset aperture device in a lens for a single-lens reflex camera comprising: an aperture ring rotatably supported within a barrel; aperture blades engaged with said aperture ring to vary the aperture defined by said blades in accordance with the rotation of said ring; a member for stopping the rotation of said aperture ring; an aperture preset ring for pre-selecting the position at which said aperture ring is stopped; electromagnetic drive means having a coil connected with a power source and with a first switch adapted to open and close in response to an aperture driving member provided in the camera; an aperture transmission member engaged with said aperture driving member of the camera, said transmission member being spring-biased to stay at an open position for maintaining said switch in its open position; and spring means for biasing said electromagnetic drive means in a direction for opening the aperture; said electromagnetic drive means being operatively connected to said aperture ring so as to rotate said aperture ring in a closing direction when said switch is closed.
Claim 2
Dependent Claim
176 words
A preset aperture device in a lens for a single-lens reflex camera comprising: an aperture ring rotatably supported within a barrel; aperture blades engaged with said aperture ring to vary the aperture defined by said blades in accordance with the rotation of said ring; a member for stopping the rotation of said aperture ring; an aperture preset ring for pre-selecting the position at which said aperture ring is stopped; electromagnetic drive means having a coil connected with a power source and with a first switch adapted to open and close in response to an aperture driving member provided in the camera; an aperture transmission member engaged with said aperture driving member of the camera, said transmission member being spring-biased to stay at an open position for maintaining said switch in its open position; and spring means for biasing said electromagnetic drive means in a direction for opening the aperture; said electromagnetic drive means being operatively connected to said aperture ring so as to rotate said aperture ring in a closing direction when said switch is closed.
Claim 3
Dependent Claim
26 words
A preset aperture device according to claim 1, further comprising a preview switch for short-circuiting a circuit including said power source and said electromagnetic drive means.
Claim 4
Dependent Claim
30 words
A preset aperture device according to claim 1, further comprising power source check-up means connected through a resistor to a circuit including said power source and said electromagnetic drive means.
Claim 5
Dependent Claim
20 words
A preset aperture device according to claim 3, wherein said power source check-up means is driven by said preview switch.
Claim 6
Dependent Claim
21 words
A preset aperture device according to claim 3, wherein said power source check-up means includes a lamp and a switching element.
Claim 7
Dependent Claim
17 words
A preset aperture device according to claim 3, wherein said power source check-up means includes an ammeter.
Claim 8
Dependent Claim
64 words
A preset aPerture device according to claim 1, wherein the circuit including said power source and said electromagnetic drive means includes a second switch connected in series with said first switch associated with said aperture driving member, and a resistor connected parallel with said second switch, said second switch being adapted to open in response to the stop-down motion of said aperture transmission member.
Claim 9
Dependent Claim
20 words
A preset aperture device according to claim 7, further comprising delay means provided between said first and said second switch.
Claim 10
Dependent Claim
34 words
A preset aperture device according to claim 1, wherein said electromagnetic drive means is operatively associated with said aperture driving member of the camera via the aperture signal transmission member of an intermediate ring.
Claim 11
Dependent Claim
164 words
A preset aperture device for single-lens reflex camera comprising in combination a camera having an aperture driving member reciprocating in connection with the shutter release of the camera and an interchangeable lens which comprises; an aperture ring rotabably supported within a barrel; aperture blades engaged with said aperture ring to vary the aperture defined by said blades in accordance with the rotation of said ring; a member for stopping the rotation of said aperture ring; an aperture preset ring for pre-selecting the position at which said aperture ring is stopped; electomagnetic drive means operatively connected with said aperture ring; a switching means provided in a circuit including said electromagnetic drive means and a power source, said switching means being actuated in response to the movement of said aperture driving member, and permitting, when closed, the rotation of said aperture ring in a closing direction through said electromagnetic drive means; spring means for biasing said electromagnetic drive means in a direction for opening the aperture.
Claim 12
Dependent Claim
164 words
A preset aperture device for single-lens reflex camera comprising in combination a camera having an aperture driving member reciprocating in connection with the shutter release of the camera and an interchangeable lens which comprises; an aperture ring rotabably supported within a barrel; aperture blades engaged with said aperture ring to vary the aperture defined by said blades in accordance with the rotation of said ring; a member for stopping the rotation of said aperture ring; an aperture preset ring for pre-selecting the position at which said aperture ring is stopped; electomagnetic drive means operatively connected with said aperture ring; a switching means provided in a circuit including said electromagnetic drive means and a power source, said switching means being actuated in response to the movement of said aperture driving member, and permitting, when closed, the rotation of said aperture ring in a closing direction through said electromagnetic drive means; spring means for biasing said electromagnetic drive means in a direction for opening the aperture.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-07-09 | 1977-01-08 | 1977-07-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-07-09 | 1981-01-08 | 1981-07-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-07-09 | 1985-01-08 | 1985-07-10 | $7700.00 | Window Closed / Lapsed |