Patent US3626826A successfully refreshed from Google Patents.
US3626826A
Expired / Lapsed
US
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Photographic apparatus with electronic exposure control means
Assignee: Agfa Gevaert AG
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Filing: 1970-09-10
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Granted: 1971-12-14
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Expires: 1990-09-10
Abstract
Abstract An electronic control for a shutter which respectively opens and closes on movement of a first and a second ring to uncocked position. The circuit of the exposure control has an electromagnet whose armature normally holds the rings in cocked positions and releases the first ring on actuation of the camera release. The second ring is released with a delay which is a function of scene brightness. The electromagnet has a permanent magnet core which is too weak to move the armature against the bias of a spring from a first retaining position in which both rings are held in cocked positions, and a winding which is energized in a first way on actuation of the camera release to assist the core in moving the armature to a second retaining position in which the armature holds only the second ring in cocked position whereby the shutter opens. The condition of energization of the winding is changed by a timer element with a delay which depends on scene brightness whereby the winding opposes the action of the core and enables the spring to displace the armature which releases the second ring to thus close the shutter.
Inventors
- 👤 Johann Putscher
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 21:38
CPC Classifications
G; G03; G03B; G03B7/00; G03B7/08; G03B7/081; G03B7/083
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
266 words
In a photographic apparatus, a combination comprising a shutter having first and second members movable between first and second positions, said shutter being respectively opened and closed in response to movement of said first and second members to their second positions; release means actuatable to move from a starting position to an operative position; and an exposure control for effecting a movement of said first member to its second position in response to actuation of said release means and thereupon of said second member to its second position with variable delay which determines the exposure time, comprising an electric circuit having a first portion including electromagnet means having a permanent magnet core, an armature which normally assumes a first retaining position wherein it holds said first member in its first position and is biased by said core to a second retaining position in which it holds said second member in its first position while releasing said first member for movement to its second position and winding means energizable in response to the actuation of said release means to assume a first condition of energization in which it cooperates with said core to move the armature to said second retaining position with the resulting opening of said shutter, said circuit further having a second portion including means for changing the condition of energization of said winding means with a delay which is a function of scene brightness so that said winding means then ceases to cooperate with said core to thereby effect a movement of said second member to its second position whereby the shutter is closed.
Claim 2
Dependent Claim
266 words
In a photographic apparatus, a combination comprising a shutter having first and second members movable between first and second positions, said shutter being respectively opened and closed in response to movement of said first and second members to their second positions; release means actuatable to move from a starting position to an operative position; and an exposure control for effecting a movement of said first member to its second position in response to actuation of said release means and thereupon of said second member to its second position with variable delay which determines the exposure time, comprising an electric circuit having a first portion including electromagnet means having a permanent magnet core, an armature which normally assumes a first retaining position wherein it holds said first member in its first position and is biased by said core to a second retaining position in which it holds said second member in its first position while releasing said first member for movement to its second position and winding means energizable in response to the actuation of said release means to assume a first condition of energization in which it cooperates with said core to move the armature to said second retaining position with the resulting opening of said shutter, said circuit further having a second portion including means for changing the condition of energization of said winding means with a delay which is a function of scene brightness so that said winding means then ceases to cooperate with said core to thereby effect a movement of said second member to its second position whereby the shutter is closed.
Claim 3
Dependent Claim
50 words
A combination as defined in claim 1, wherein said electric circuit further comprises a source of DC current and said means for changing the condition of energization of said winding means comprises a timer element having capacitor means in series with photosensitive receiver means which is exposed to scene light.
Claim 4
Dependent Claim
67 words
A combination as defined in claim 1, wherein said armature comprises a lever which is pivotable between said first and second retaining positions, said lever having a first portion which holds said first member in its first position in the first retaining position of said lever and a second portion which holds said second member in its second position in the second retaining position of said lever.
Claim 5
Dependent Claim
37 words
A combination as defined in claim 1, wherein said winding means in the first condition of energization thereof strengthens the magnetic flux in said core and weakens such magnetic flux in the second condition of energization thereof.
Claim 6
Dependent Claim
23 words
A combination as defined in claim 1, wherein said first portion of said circuit further comprises switch means actuatable by said electromagnet means.
Claim 7
Dependent Claim
66 words
A combination as defined in claim 1, wherein said armature comprises a two-armed lever which is pivotable between said first and second retaining positions and further comprising means for biasing said lever to the first retaining position with a force which is stronger than the bias of said core in the changed condition of energization of said winding means and when said winding means is deenergized.
Claim 8
Dependent Claim
60 words
A combination as defined in Claim 6, wherein one arm of said lever has a projection which holds said first member in its first position in the first retaining position of said lever and the other arm of said lever comprises a portion which holds the second member in its first position in the second retaining position of said lever.
Claim 9
Dependent Claim
34 words
A combination as defined in claim 1, wherein the first member of said shutter comprises means for holding said second member in the first position while said first member dwells in its first position.
Claim 10
Dependent Claim
55 words
A combination as defined in claim 1, wherein said second member has a first projection and said first member has a second projection which engages said first projection to move said second member from its second to its first position in response to movement of said first member from its second to its first position.
Claim 11
Dependent Claim
57 words
A combination as defined in claim 1, wherein the first member of said shutter has a first projection and said armature has a second projection which is located in the path of said first projection to hold said first member against movement from its first to its second position in the first retaining position of said armature.
Claim 12
Dependent Claim
123 words
A combination as defined in claim 1, wherein in said electric circuit further comprises a source of DC current having a positive and a negative pole, said winding means having first and second terminals and said first portion of said circuit further comprising adjustable first and second two-way switch means which respectively connect said first and second terminals with the positive and negative poles of said source in response to actuation of said release means, said switch means being adjustable by said electromagnet means in the first condition of energization of said winding means to thereby partially complete the circuit of said winding means so that said first and second terminals are respectively connected with the negative and positive poles of said source.
Claim 13
Dependent Claim
57 words
A combination as defined in claim 11, wherein said second portion of said circuit comprises transistor means arranged to complete the circuit of said winding means to thus effect said change in the condition of energization of said winding means in adjusted positions of said switch means with a delay which is a function of scene brightness.
Claim 14
Dependent Claim
57 words
A combination as defined in claim 12, wherein said second portion of said electric circuit further comprises capacitor means, photosensitive receiver means exposed to scene light and in series with said capacitor means, and a Zener diode connected to the base of said transistor means and to a tap between said capacitor means and said receiver means.
Claim 15
Dependent Claim
23 words
A combination as defined in claim 13, wherein said capacitor means and said receiver means constitute a timer element which determines said delay.
Claim 16
Dependent Claim
83 words
A combination as defined in claim 1, wherein said first portion of said electric circuit further comprises adjustable switch means for directly connecting said winding means to an energy source, said switch means being adjustable by said electromagnet means in the first condition of energization of said winding means to thereby indirectly connect said winding means to the source, said circuit further comprising storage capacitor means connected in parallel with said first and second portions in the adjusted positions of said switch means.
Claim 17
Dependent Claim
52 words
A combination as defined in claim 1, wherein said first portion of said electric circuit further comprises a master switch which is closed on actuation of said release means and an auxiliary switch connected in parallel with said master switch and arranged to close in response to energization of said winding means.
Claim 18
Dependent Claim
32 words
A combination as defined in claim 16, wherein said auxiliary switch is normally open and is closed by said armature in response to movement from the first to second retaining position thereof.
Claim 19
Dependent Claim
154 words
A combination as defined in claim 1, wherein said circuit further comprises a source of DC current having positive and nEgative poles and said second portion of said circuit comprises a transistor, said first portion of said circuit further including a first relay switch having a first contact connected with one of said poles, a second contact connectable with the other of said poles, and a third contact movable by said electromagnet means from the one to the other of said first and second contacts and connected with one terminal of said winding means, and a second relay switch having a first contact connected with said one pole, a second contact connected to the collector of said transistor, and a third contact connected with the other terminal of said winding means and movable by said electromagnet means from the one to the other of the first and second contacts of said second relay switch.
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) | 1974-12-13 | 1975-06-14 | 1975-12-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-12-13 | 1979-06-14 | 1979-12-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-12-13 | 1983-06-14 | 1983-12-14 | $7700.00 | Window Closed / Lapsed |