Patent US2353694A successfully refreshed from Google Patents.
US4059352A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Slide projector
Assignee: Siemens AG
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Filing: 1976-05-05
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Granted: 1977-11-22
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Expires: 1996-05-05
Abstract
Abstract A slide projector comprising a slide magazine with a motor drive, a motor-driven pusher for conveying respective slides one by one from the slide magazine into the path of the light of an optical system, and a guide unit for guiding the slides. A mechanical stop is provided for establishing the projection position of the slides and a spring is interposed between the pusher and its motor drive for transmitting force therebetween. For displacing the pusher there is provided a roller guided in a curved slot in a disk connected to the motor.
Inventors
- 👤 Ulrich Bar
- 👤 Martin Schmidt
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 06:36
CPC Classifications
G; G03; G03B; G03B23/00; G03B23/02; G03B23/06
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
245 words
A slide projector comprising an optical projection system, a slide magazine being mounted for displacement, a drive motor coupled to said magazine for displacing the magazine, mechanical stop means for positioning a slide in a projection position in the projection system, guide means for guiding a slide as it is moved to the projection position, and pusher means for moving a slide from the magazine along the guide means to the projection position and for returning the slide back to said magazine, said pusher means including a pusher member being mounted for back and forth movement along a linear path, said member having two tongues extending toward one another and spaced apart to enable the magazine to move therebetween, one of the two tongues being for ejecting a slide from the magazine and the other of the two tongues being for pushing a slide back into the magazine, an electromotor, a disk having a curved slot coupled to said electromotor to move therewith, a roller being engaged in said slot, and means mounting the roller for movement in a linear path and including a spring for transferring linear displacement of the roller to the pusher member, said curved slot having a shape so that as the other tongue pushes the slide back into the magazine, it is inserted into said magazine and is then withdrawn from the magazine to a final position which enables the magazine to be freely displaced between the two spaced tongues.
Claim 2
Dependent Claim
245 words
A slide projector comprising an optical projection system, a slide magazine being mounted for displacement, a drive motor coupled to said magazine for displacing the magazine, mechanical stop means for positioning a slide in a projection position in the projection system, guide means for guiding a slide as it is moved to the projection position, and pusher means for moving a slide from the magazine along the guide means to the projection position and for returning the slide back to said magazine, said pusher means including a pusher member being mounted for back and forth movement along a linear path, said member having two tongues extending toward one another and spaced apart to enable the magazine to move therebetween, one of the two tongues being for ejecting a slide from the magazine and the other of the two tongues being for pushing a slide back into the magazine, an electromotor, a disk having a curved slot coupled to said electromotor to move therewith, a roller being engaged in said slot, and means mounting the roller for movement in a linear path and including a spring for transferring linear displacement of the roller to the pusher member, said curved slot having a shape so that as the other tongue pushes the slide back into the magazine, it is inserted into said magazine and is then withdrawn from the magazine to a final position which enables the magazine to be freely displaced between the two spaced tongues.
Claim 3
Dependent Claim
25 words
A slide projector according to claim 1, wherein said curved slot is also configured so that the pusher member is accelerated and halted substantially sinuoidally.
Claim 4
Dependent Claim
51 words
A slide projector according to claim 1, which includes a first bar, said pusher member being supported for linear displacement along said bar, and wherein the means for mounting the roller includes a transfer block displaceable on said bar, said transfer block being coupled to said pusher member by said spring.
Claim 5
Dependent Claim
17 words
A slide projector according to claim 3, wherein said roller is mounted directly on said transfer block.
Claim 6
Dependent Claim
49 words
A slide projector according to claim 1, wherein the guide means for guiding the slide comprises a lower support plate, an upper support plate including laterally disposed springs resting on the edges of a slide as it is inserted therebetween and urging the slide against said lower support plate.
Claim 7
Dependent Claim
19 words
A slide projector according to claim 5, wherein said mechanical stop means are disposed on said lower support plate.
Claim 8
Dependent Claim
31 words
A slide projector according to claim 1, wherein said electromotor is a step motor which during each cycle of the pusher means oscillates the disk through an arc of approximately 180°.
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) | 1980-11-21 | 1981-05-23 | 1981-11-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-11-21 | 1985-05-23 | 1985-11-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-11-21 | 1989-05-23 | 1989-11-22 | $7700.00 | Window Closed / Lapsed |