US3893140A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Automatic exposure time control apparatus for camera
Assignee: Minolta Co Ltd
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Filing: 1972-03-01
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Granted: 1975-07-01
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Expires: 1992-03-01
Abstract
Abstract A group of terminals for manual exposure setting to be selected by a manual selector are respectively connected to a resistor by lead wires which are spaced apart over the length thereof and through which resistance values corresponding to respective exposure times are obtained stepwise. By means of conductors, the group of the terminals are each connected to another group of terminals to be selected automatically at the position which corresponds to the intensity of incident light from the subject. The operation to close the shutter is controlled by an electromagnet which is operated by an RC integrating circuit actuated with the resistance value of the resistor determined alternatively by one of the two terminal groups and a transistor circuit connected to the integrating circuit. The groups of the terminals, the resistor and conductors connecting these elements are assembled into a single set.
Inventors
- 👤 Kintaro Yata
- 👤 Yoshio Kuramoto
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 17:20
CPC Classifications
G; G03; G03B; G03B7/00; G03B7/08; G03B7/081; G03B7/083; G03B9/00; G03B9/58
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
226 words
A network in an automatic exposure time controlling device for a camera comprising an automatic terminal and a group of terminals for manual exposure setting to be selected by a manual selector, said terminals of said group of terminals being connected respectively to a resistance means by lead wires which are spaced along the length thereof and through which resistance values corresponding to respective exposure times are obtained stepwise; another group of terminals to be selected automatically at the position which corresponds to the intensity of incident light from the subject and including an electrically conductive member connected to said automatic terminal and occupying a position responsive to said incident light intensity for engagement with a corresponding terminal of said other group; and shutter actuating means for closing a shutter to be controlled by an electromagnet which is operated by an RC integrating circuit actuated with the resistance value of said resistance means determined alternatively by one of said two groups of terminals, wherein a first insulating base carries said resistance means and a first of said group of terminals; a second insulating base carries a second of said groups of terminals; mutually insulated conductors connect said first group of terminals to respective spaced points along said resistance means; and conductor means connect said first group of terminals to corresponding terminals of said second group respectively.
Claim 2
Dependent Claim
226 words
A network in an automatic exposure time controlling device for a camera comprising an automatic terminal and a group of terminals for manual exposure setting to be selected by a manual selector, said terminals of said group of terminals being connected respectively to a resistance means by lead wires which are spaced along the length thereof and through which resistance values corresponding to respective exposure times are obtained stepwise; another group of terminals to be selected automatically at the position which corresponds to the intensity of incident light from the subject and including an electrically conductive member connected to said automatic terminal and occupying a position responsive to said incident light intensity for engagement with a corresponding terminal of said other group; and shutter actuating means for closing a shutter to be controlled by an electromagnet which is operated by an RC integrating circuit actuated with the resistance value of said resistance means determined alternatively by one of said two groups of terminals, wherein a first insulating base carries said resistance means and a first of said group of terminals; a second insulating base carries a second of said groups of terminals; mutually insulated conductors connect said first group of terminals to respective spaced points along said resistance means; and conductor means connect said first group of terminals to corresponding terminals of said second group respectively.
Claim 3
Dependent Claim
33 words
The network as set forth in claim 1, wherein said resistance means is of arcuate form and said first group of terminals (31-3n) are disposed along the inner side of said resistance means.
Claim 4
Dependent Claim
28 words
The network as set forth in claim 1, wherein a terminal for automatic exposure time control is disposed concentric with and apart from said first group of terminals.
Claim 5
Dependent Claim
70 words
The automatic exposure time controlling device for a camera as set forth in claim 1, wherein a terminal for connecting said resistance means to a circuit capacitor is disposed at one end of said resistance means and including a light meter having an electrically conducting needle defining said conductive member and means for selectively urging and clamping said needle into engagement with a registering terminal of said automatically selected group.
Claim 6
Dependent Claim
20 words
The network as set forth in claim 1, wherein said second group of terminals are disposed along an arcuate path.
Claim 7
Dependent Claim
40 words
The network as set forth in claim 1, including a thin flexible insulator band extending between said base sections and supporting said conductor means extending between said resistance means and said second group of terminals on said second base section.
Claim 8
Dependent Claim
21 words
The network as set forth in claim 1, wherein said base sections are made of a thin insulating synethetic resin material.
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) | 1978-06-30 | 1978-12-30 | 1979-07-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-06-30 | 1982-12-30 | 1983-07-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-06-30 | 1986-12-30 | 1987-07-01 | $7700.00 | Window Closed / Lapsed |