US3692394A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Motion picture camera motor control
Assignee: Anton Bauer Inc
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Filing: 1970-12-14
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Granted: 1972-09-19
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Expires: 1990-12-14
Abstract
Abstract A motion picture camera with a rotary shutter which, as it rotates, periodically permits an image from the camera lens to reach the film, and then reflects the image to the eyepiece, etc. Motor controls are provided for controlling the speed of the shutter so that the shutter automatically stops at a location in which it blocks and reflects images to the eyepiece rather than one in which images are permitted to reach the film. A pulse generator operates synchronously with the rotary shutter. During stopping of the shutter, whenever the speed of the shutter is insufficient to bring it to a stop at the desired location, the pulse generator produces electrical pulses whose energy would decrease as the position of the shutter changes, but for the decrease in speed of the shutter, and these pulses are fed to the shutter drive motor to control its speed at a level sufficient to bring it to the desired location. Preferably, the pulse generator includes a transparent disc with opaque lines spaced around it, together with an infrared light source and a phototransistor. The spacing between adjacent opaque lines gradually decreases at successive positions around the disc, and a relatively large opaque area is provided on the disc in the vicinity of the position in which the shutter is to be stopped.
Inventors
- 👤 George W Bauer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 23:41
CPC Classifications
G; G03; G03B; G03B9/00; G03B9/08; G03B9/10; G03B19/00; G03B19/18
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
134 words
In a motion picture camera having a rotary shutter and drive means for rotating said shutter, shutter drive control means including means for delivering to said drive means electrical energy in an amount sufficient to prevent said shutter from stopping before it reaches a pre-determined rotational position, and for decreasing said energy substantially to zero when said shutter reaches said pre-determined rotational position so as to stop said shutter adjacent said position, said control means including a rotor with indicia spaced therearound, the spacing between said indicia decreasing progressively around said rotor, means for coupling said rotor to said shutter for rotation therewith, means for detecting said indicia as said rotor rotates and controlling said energy in accordance with the time between the passage of adjacent ones of said indicia past said detecting means.
Claim 2
Dependent Claim
134 words
In a motion picture camera having a rotary shutter and drive means for rotating said shutter, shutter drive control means including means for delivering to said drive means electrical energy in an amount sufficient to prevent said shutter from stopping before it reaches a pre-determined rotational position, and for decreasing said energy substantially to zero when said shutter reaches said pre-determined rotational position so as to stop said shutter adjacent said position, said control means including a rotor with indicia spaced therearound, the spacing between said indicia decreasing progressively around said rotor, means for coupling said rotor to said shutter for rotation therewith, means for detecting said indicia as said rotor rotates and controlling said energy in accordance with the time between the passage of adjacent ones of said indicia past said detecting means.
Claim 3
Dependent Claim
46 words
Apparatus as in claim 1 in which said shutter has at least one blocking portion which, when in an operative position, prevents images from reaching the film in said camera, and in which said energy decreases to zero when said blocking portion reaches said operative position.
Claim 4
Dependent Claim
55 words
Apparatus as in claim 1 in which said shutter has at least one blocking portion which, when in an operative position, prevents images from reaching the film in said camera, and in which said blocking portion reflects said images back to the eyepiece of said camera when said blocking portion is in said operative position.
Claim 5
Dependent Claim
88 words
A motion picture camera including a camera lens, a rotary reflective shutter, a film guide, a motor for driving said shutter, and control means for stopping said shutter in a reflective position, said control means including pulse generator means for selectively delivering to said motor electrical pulses each of whose energy varies directly with the angular distance of a first point on said shutter from a reference location, inversely with the speed of said shutter, and decreases substantially to zero when said shutter is adjacent said reflective position.
Claim 6
Dependent Claim
88 words
A motion picture camera including a camera lens, a rotary reflective shutter, a film guide, a motor for driving said shutter, and control means for stopping said shutter in a reflective position, said control means including pulse generator means for selectively delivering to said motor electrical pulses each of whose energy varies directly with the angular distance of a first point on said shutter from a reference location, inversely with the speed of said shutter, and decreases substantially to zero when said shutter is adjacent said reflective position.
Claim 7
Dependent Claim
54 words
A camera as in claim 4 incLuding means for starting said pulse generator when said shutter reaches a first rotational position, and means for stopping said pulse generator when said shutter reaches a second rotational position at which said first point has reached said reference location and said shutter is adjacent said reflective position.
Claim 8
Dependent Claim
74 words
A camera as in claim 5 in which said pulse generator includes a rotor which rotates with said shutter, said rotor having arcuately spaced linear indicia thereon, the spacing between said indicia decreasing between a first line corresponding to said first rotational position of said shutter and a second line corresponding to said second rotational position of said shutter, and a detector positioned to detect said indicia and produce said pulses in response thereto.
Claim 9
Dependent Claim
34 words
A camera as in claim 6 including charge storage means for storing charge to develop pulses in the time intervals between passage of adjacent ones of said indicia past said source and said detector.
Claim 10
Dependent Claim
103 words
In a motion picture camera having a rotary shutter, a drive motor for rotating said shutter, shutter drive control means including a rotor coupled to rotate with said shutter, said rotor having indicia angularly spaced thereon, means for detecting said indicia and producing electrical pulses in response to the detection of said indicia, said indicia being spaced progressively closer together around said rotor in a predetermined direction, means for energizing said motor with said pulses, and means for substantially stopping said pulses when said rotor is near a pre-determined position in which said shutter prevents images from reaching the film in said camera.
Claim 11
Dependent Claim
103 words
In a motion picture camera having a rotary shutter, a drive motor for rotating said shutter, shutter drive control means including a rotor coupled to rotate with said shutter, said rotor having indicia angularly spaced thereon, means for detecting said indicia and producing electrical pulses in response to the detection of said indicia, said indicia being spaced progressively closer together around said rotor in a predetermined direction, means for energizing said motor with said pulses, and means for substantially stopping said pulses when said rotor is near a pre-determined position in which said shutter prevents images from reaching the film in said camera.
Claim 12
Dependent Claim
45 words
Apparatus as in claim 8 in which said indicia are opaque regions with transparent regions between said opaque regions on said rotor, said detecting means including a radiation source and a radiation-responsive detector device positioned to receive radiation from said source through said transparent regions.
Claim 13
Dependent Claim
22 words
Apparatus as in claim 9 in which said radiation source is a light-emitting diode and said radiation-responsive detector device is a phototransistor.
Claim 14
Dependent Claim
74 words
Apparatus as in claim 9 in which the angular extent of said transparent regions between said opaque regions decreases to zero from an initial value at a starting position when said rotor rotates in said predetermined direction past said source and detector device, and electrical charge storage means operated by said detector device for developing said pulses, the amount of energy in each pulse being determined by the charge stored in said storage means.
Claim 15
Dependent Claim
36 words
Apparatus as in claim 11 including on said rotor an opaque region of relatively great angular extent between said starting position and the position at which the angular extent of the transparent spaces drops to zero.
Claim 16
Dependent Claim
22 words
A device as in claim 8 including means for setting a minimum motor speed above which said electrical pulses are not produced.
Claim 17
Dependent Claim
52 words
A device as in claim 13 in which the detecting means includes charge storage means for storing charge between adjacent ones of said indicia, and level detector means for detecting the level of charge on said storage means and starting one of said electrical pulses when the charge reaches a pre-determined level.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-09-19 | 1976-03-20 | 1976-09-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-09-19 | 1980-03-20 | 1980-09-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-09-19 | 1984-03-20 | 1984-09-19 | $7700.00 | Window Closed / Lapsed |