US3705764A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Motion picture camera for the making of exposures with fixed and variable exposure times
Assignee: Robert Bosch Photokino GmbH
•
Filing: 1971-11-29
•
Granted: 1972-12-12
•
Expires: 1991-11-29
Abstract
Abstract A motion picture camera wherein the shutter is adjustable by a knob between a first position in which it shields the film from scene light upon completion of each of its cycles and a second position in which it exposes the foremost unexposed film frame to scene light upon completion of each cycle. The film is transported by an intermittent which is driven by a motor serving to move the shutter through a cycle during each transport of the film by the length of a frame. When the shutter is adjusted to assume its second position, the motor is operated by an electric timer which transmits signals for energization of an electromagnet at intervals whose length is a function of scene brightness. The armature of the electromagnet starts the motor which causes the intermittent to advance the film by the length of a frame and which also causes the shutter to complete a cycle in response to each energization of the electromagnet. This enables the camera to make any desired number of successive time lapse exposures with ''''long'''' exposure times (e.g., in the range of one or more seconds or minutes), always as a function of scene brightness.
Inventors
- 👤 Herbert Reinsch
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 18:00
CPC Classifications
G; G03; G03B; G03B19/00; G03B19/18
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
159 words
In a motion picture camera, a combination comprising a mechanism operative to intermittently transport the film by the length of a frame; a cyclically movable shutter, said shutter being adjustable between first and second positions in which the shutter respectively shields the film from and exposes the film to scene light upon completion of each cycle; selector means for effecting adjustments of said shutter; arresting means for releasably holding the shutter against movement in said second position thereof; drive means actuatable to operate said mechanism and to move said shutter; and control means including timer means arranged to produce signals at a frequency which is a Function of scene brightness and actuating means for temporarily disengaging said arresting means from said shutter so that the latter can complete a cycle and for actuating said drive means so that the latter can effect the transport of film by the length of a frame in response to each of said signals.
Claim 2
Dependent Claim
159 words
In a motion picture camera, a combination comprising a mechanism operative to intermittently transport the film by the length of a frame; a cyclically movable shutter, said shutter being adjustable between first and second positions in which the shutter respectively shields the film from and exposes the film to scene light upon completion of each cycle; selector means for effecting adjustments of said shutter; arresting means for releasably holding the shutter against movement in said second position thereof; drive means actuatable to operate said mechanism and to move said shutter; and control means including timer means arranged to produce signals at a frequency which is a Function of scene brightness and actuating means for temporarily disengaging said arresting means from said shutter so that the latter can complete a cycle and for actuating said drive means so that the latter can effect the transport of film by the length of a frame in response to each of said signals.
Claim 3
Dependent Claim
39 words
A combination as defined in claim 1, wherein said timer means comprises photoelectric receiver means exposed to scene light and capacitor means which is charged at the rate determined by said receiver means as a function of scene brightness.
Claim 4
Dependent Claim
62 words
A combination as defined in claim 2, further comprising adjustable diaphragm means, electric adjuster means for said diaphragm means, and switch means for connecting said photoelectric receiver means in circuit with said adjuster means in the first position of said shutter so that the size of the aperture furnished by said diaphragm means varies as a function of changes in scene brightness.
Claim 5
Dependent Claim
15 words
A combination as defined in claim 3, wherein said switch means is actuatable by hand.
Claim 6
Dependent Claim
49 words
A combination as defined in claim 1, wherein said control means further comprises a thyristor having an anode and a gate, said actuating means being connected in the anode circuit of said thyristor and said timer means being arranged to transmit said signals to the gate of said thyristor.
Claim 7
Dependent Claim
44 words
a combination as defined in claim 5, wherein said control means further comprises normally closed switch means in the anode circuit of said thyristor, said switch means being arranged to open and to turn off said thyristor in response to each of said signals.
Claim 8
Dependent Claim
17 words
A combination as defined in claim 6, wherein said switch means is opened by said actuating means.
Claim 9
Dependent Claim
42 words
A combination as defined in claim 1, wherein said actuating means comprises an electromagnet which is energized in response to said signals and comprises an armature arranged to disengage said arresting means from said shutter in response to energization of said electromagnet.
Claim 10
Dependent Claim
106 words
A combination as defined in claim 8, wherein said control means further comprises a thyristor having an anode and a gate, a normally closed first switch in the anode circuit of said thyristor and a normally open second switch in circuit with said drive means, said electromagnet being connected in the anode circuit of said thyristor and said timer means being arranged to transmit said signals to the gate of said thyristor, said armature being arranged to open said first switch in response to energization of said electromagnet to thereby turn off said thyristor and to close said second switch to thereby actuate said drive means.
Claim 11
Dependent Claim
45 words
A combination as defined in claim 9, further comprising a holding circuit for said electromagnet, said holding circuit including capacitor means arranged to maintain said electromagnet in energized condition for a predetermined interval of time following the opening of said first switch by said armature.
Claim 12
Dependent Claim
48 words
A combination as defined in claim 1, wherein said control means further comprises normally open switch means connected in circuit with said drive means to start said drive means in response to each manipulation of said selector means whereby said drive means changes the position of said shutter.
Claim 13
Dependent Claim
32 words
A combination as defined in claim 1, further comprising master switch means for completing the circuit of said timer means in response to adjustment of said shutter to assume said second position.
Claim 14
Dependent Claim
35 words
A combination as defined in claim 1, wherein said shutter is a rotary shutter having a single blade and said drive means comprises a shaft supporting said blade and having means for operating said mechanism.
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) | 1975-12-12 | 1976-06-12 | 1976-12-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-12-12 | 1980-06-12 | 1980-12-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-12-12 | 1984-06-12 | 1984-12-12 | $7700.00 | Window Closed / Lapsed |