JPH0434513Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention is a shutter curtain control device for a focal plane shutter, particularly a shutter curtain control device for a focal plane electronic shutter that can mechanically maintain the shutter in an open state. Regarding.

[Background of the idea]

The shutter curtain of a focal plane shutter is provided just in front of the film aperture of the camera, and in a normal camera it always covers the film aperture except when the film is being exposed. Therefore, when the back cover of the camera is opened, the shutter curtain is left exposed through the film aperture, so when removing or loading film, it is possible to accidentally touch the shutter curtain and deform it. There was a risk that the shutter would not operate smoothly. In order to prevent such shutter failures, for example, a camera equipped with a shutter curtain protection device configured to retract the shutter curtain outside the film aperture when the back cover is open has been developed, for example in Japanese Patent Laid-Open No. 1983-1999. Disclosed in publications such as No. 79341,
It is already publicly known.

However, in the conventional shutter control device using a so-called energized attraction type magnet, which locks the leading and trailing shutter curtains when energized and releases the lock when energized, it is difficult to open the back cover as described above. There was no device that could open the shutters in conjunction with each other.

[Purpose of invention]

The object of the present invention is to provide a device for opening the shutter when the back cover is opened in a shutter control device that uses two current-carrying magnets to control the leading and trailing shutter curtains, respectively.

[Summary of the idea]

In order to achieve the above object, the present invention provides a shutter control device that uses two current-carrying magnets to control the leading and trailing shutter curtains. The technical point is to release only the mechanical locking of the leading curtain driving means without energizing two magnets and without releasing the mechanical locking of the trailing blade driving means.

〔Example〕

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. FIG. 1 is a block diagram of a control system showing one embodiment of the present invention. In FIG. 1, a shutter dial 1 is provided with a symbol "B" indicating a valve and a symbol "T" indicating a time, in addition to a number indicating shutter seconds, and an index 2 has the respective symbols and numbers. By matching, the respective shutter operating modes are set. In addition to a code pattern (not shown) for generating a shutter speed value signal, the shutter dial 1 is provided with a valve set detection switch SWb and a time set detection switch SWt in conjunction with each other to set the shutter dial 1 to valve "B". When the valve set detection switch SWb is turned ON, the time “T” is also turned on.
When the time set detection switch SWt is set to
They are configured to turn on and output low-level signals. The back cover switch SWc is a switch that is linked to the opening and closing of the camera back cover 3. When the back cover 3 is opened, it is switched from the OFF state to the ON state, and it detects the opening operation of the back cover 3 and outputs a low level signal. . These detection signals are all sent to a microprocessor (hereinafter referred to as "microcomputer") 4.
sent to.

The release switch SWr is a switch that is turned on when the release button 5 is pressed, and a detection signal from the release switch SWr that detects the pressing is also sent to the microcomputer 4. Microcomputer 4 is the switch mentioned above.
The leading curtain control circuit 6, the trailing curtain control circuit 7 and the motor drive control circuit 8 receive detection signals generated by ON and OFF of SWb, SWt, SWc and SWr.
and sends a signal to the front curtain 9A and rear curtain 9 of the shutter.
Controls the running timing of motor B and the driving and stopping of motor M.

The front curtain drive member 10, which is connected to the front curtain 9A via an interlocking lever (not shown), is rotatably supported by a support shaft 11, and is driven by a drive spring via a charge mechanism (not shown) driven by a motor M. 1
The shutter locking member 13 is rotated counterclockwise to the charge position shown in FIG.
The leading curtain locking part 13a and the claw part 1 of the leading curtain driving member 10
0a, the leading curtain 9A is locked at the charge position covering the film aperture 30. Motor M that rotationally drives the front curtain drive member 10
stops when the charge mechanism (not shown) returns to its original position. The front curtain drive member 10 is provided with an iron piece 14 that is attracted to the front curtain magnet Mg ₁ when it is excited. Even if the leading curtain 9A is separated from the claw portion 10a, it is configured to hold the leading curtain 9A at the charge position.

The leading curtain drive member 15 is also connected to the trailing curtain 9B via an interlocking lever (not shown), and is rotatably supported by a support shaft 16. Further, the trailing curtain drive member 15 is rotated counterclockwise through a charge mechanism (not shown) driven by the motor M to a charge position against the biasing force of the drive spring 17, so that the trailing curtain drive member 15 is By engaging the curtain locking portion 13b and the claw portion 15a of the trailing curtain drive member 15, the trailing curtain 9B is locked together with the trailing curtain drive member 15 at the charge position retracted from the film aperture 30. After the rear curtain 9B is locked, the charge mechanism (not shown) returns to its original position before charging by driving the motor M. When the trailing curtain magnet Mg ₂ is excited at the charge position, the iron piece 18 provided on the trailing curtain drive member 15 is attracted to the magnet Mg ₂ , and the iron piece 18 is attached to the trailing curtain locking portion 13b of the shutter locking member 13.
Even if the rear curtain 9B is separated from the claw portion 15a of the rear curtain drive member 15, the rear curtain 9B is held at the charge position.

The leading curtain magnet Mg ₁ is excited by power supplied from the leading curtain control circuit 6 to hold the leading curtain drive member 10 together with the leading curtain 9A in the charge position, and when the power supply is cut off and the excitation is stopped, the iron piece 14 is released and the leading curtain drive member 10 is released. Further, the trailing curtain magnet Mg ₂ is excited by the power supplied from the trailing curtain control circuit 7 to hold the trailing curtain drive member 15 together with the trailing curtain 9B in the charge position, and when the power supply is cut off and the excitation is stopped. , the adsorption of the iron piece 18 is released and the trailing blade drive member 15 is released. A shutter locking member 13 that mechanically locks the leading curtain driving member 10 and the trailing curtain driving member 15 is driven by a motor M and moves in the direction of arrow A.
It is pressed by a moving member 19 that is movable in the direction of arrow B, and is configured to move in parallel in the direction of arrow B against the biasing force of spring 20. By this movement of the shutter locking member 13 in the direction of arrow B, first, the leading shutter locking portion 13a and the claw portion 10a of the leading curtain driving member 10 are disengaged, and then the first motor control switch _SW1 is activated. Can be switched from ON to OFF. Further, when the moving member 19 is displaced in the direction of arrow A, the trailing curtain locking portion 13b of the shutter locking portion 13 and the claw portion 15a of the trailing curtain locking member 15 are disengaged, and then the second
The motor control switch SW ₂ is configured to be switched from ON to OFF. The first motor control switch SW ₁ and the second motor control switch SW ₂ are
The low level signal emitted by turning OFF is
Each is sent to microcomputer 4.

Further, a third motor control switch _SW3 is provided which operates at the end of the travel of the trailing curtain 9B in conjunction with the rotation of the trailing curtain drive member 15, and its detection signal is also transmitted to the microcomputer 4.
sent to. In response to this detection signal, the motor M rotates in reverse, the moving member 19 and the shutter locking member 13 return to their original positions, and the leading curtain driving member 10 and the trailing curtain driving member 15 are rotated by their respective drive springs 12 and 17. It is configured to return to the charge position shown in FIG. 1 against the urging force of. Furthermore, when the valve set detection switch 5Wb is ON, that is, when the shutter dial 1 is set to valve "B", the shutter will be released only while the release button 5 is pressed and the release switch SWr is ON. The shutter is opened, and when the release button 5 is released, the shutter is closed. Also, when the time set detection switch SWt is ON, that is, when the shutter dial 1 is set to time "T", the release button 5 is pressed first to turn the release switch SWr ON. Therefore, the shutter is opened, and the shutter is closed by pressing the release button 5 again and turning on the release switch SWr.

Next, the operation of the embodiment shown in FIG. 1 will be explained using the flowchart shown in FIG.

The microcomputer 4 starts when it receives a switching signal for each switch caused by a setting operation of the shutter dial 1, an opening/closing operation of the back cover 3, or a half-pressing of the release button 5. When the microcomputer 4 starts operating, it is first determined whether the back cover 3 is closed or not based on a signal from the back cover switch SWc (step 100). When the back cover 3 is closed,
Release button 5 is pressed and release switch SWr
Wait until it turns ON (step 101). After that, the release button 5 is pressed and the release switch
Upon receiving the ON signal from SWr, microcontroller 4
The leading curtain control circuit 6 and the trailing curtain control circuit 7 are operated to excite the leading curtain magnet Mg ₁ and the trailing curtain magnet Mg ₂ (step 102). This Mg ₁ and Mg ₂
By this excitation, both the leading curtain drive member 10 and the trailing curtain drive member 15, which are locked in the shutter charge position by the shutter locking member 13, are restrained in the shutter charge position shown in FIG.

Furthermore, the microcomputer 4 sends a signal to the motor drive circuit to drive the motor M (step 103).
By driving this motor M, the shutter locking member 1
3 is displaced in the direction of arrow B, and first the leading curtain drive member 10
(step 104), and then turn off the first motor control switch _SW1 (step 105). However, in this state, the leading curtain 9A and the trailing curtain 9B do not run because they are restrained by the magnets Mg ₁ and Mg ₂ .

Upon receiving the OFF signal from the first motor control switch _SW1 , the microcomputer 4 first determines whether or not the shutter dial 1 is set to valve "B" based on the detection signal from the valve set detection switch SWb. (Step 106), and if the valve is not set to "B", that is, if SWb is OFF, the time set detection switch SWt is further determined to see if shutter dial 1 is set to time "T". The determination is made based on the detection signal from (step 107). In this step 107, if the shutter dial 1 is not set to time "T", that is, if OFF signals are received from both SWb and SWt, the motor M continues to drive and the shutter is not locked. The member 13 is further displaced in the direction of arrow B, and the trailing curtain drive member 15 is unlocked (step 108). In addition, the second motor control switch is
When SW ₂ turns OFF (step 109), the microcomputer 4 that received the OFF signal sends a signal to the motor drive control circuit 8 to stop the motor M (step 110).
let Furthermore, a signal is sent to the front curtain control circuit 6,
Stop excitation of front curtain magnet Mg ₁ (step
111), the restraint of the front curtain drive member 10 is released, and the front curtain 9A is made to travel (step 112). here,
After a delay time corresponding to the shutter speed set with the shutter dial 1, the microcomputer 4 sends a signal to the trailing curtain control circuit 7 to stop excitation of the trailing curtain magnet Mg ₂ (step 113), and Release the restraint of the drive member 15 and run the rear curtain 9B (step
114) and end the exposure.

At the end of the running of the trailing curtain 9B, the third motor control switch _SW3 is turned ON (step 115) in conjunction with the trailing curtain driving member 15, and a trailing curtain running end signal is sent to the microcomputer 4. The microcomputer 4, which has received this trailing curtain run end signal, sends a motor reversal signal to the motor drive control circuit 8, and drives the motor M in the reverse direction (step
116) Let. By reversing the motor M, film winding and shutter charging are performed (step 117), and the moving member 19 and shutter locking member 13
and the front curtain 9A returns to its original position, and the front curtain 9A is moved to the front curtain drive member 1.
0, the trailing curtain 9b returns to the charge position shown in FIG. 1 together with the trailing curtain driving member 15. When the trailing curtain drive member 15 returns to the charge position, the third motor control switch SW ₃ is turned OFF, and the motor M
stops driving (step 118), and the microcomputer 4 stops its operation.

On the other hand, if the ON signal is output from either the valve set detection switch SWb or the time set detection switch SWt in steps 106 and 107, that is, the shutter dial 1 is set to valve "B" or time "T". If so, the motor M is immediately stopped by the OFF signal of the first motor control switch SW ₁ (step 120), and the leading curtain control circuit 6 is stopped by the subsequent signal from the microcomputer 4.
and the trailing curtain control circuit 7 respectively stop the excitation of the leading curtain magnet Mg ₁ and the trailing curtain magnet Mg ₂ (step 121). As a result, the leading curtain 9A runs (step 122) and opens the shutter, but
The trailing curtain drive member 15 is locked by the trailing curtain locking portion 13b of the shutter locking member 13 even if the binding of the trailing curtain magnet Mg ₂ is released. Therefore, the rear curtain 9B does not run and the shutter remains open.

Here, the time set detection switch SWt is turned ON.
It is determined whether or not (step 123). When the time set detection switch SWt is ON, that is, the shutter dial 1 is set to time "T", the shutter dial is switched to another set position and the time set detection switch SWt is turned on.
Waits until OFF (step 124). Also, time set detection switch SWt is OFF.
In this case, valve set detection switch SWb is
Since it is ON, the release switch SWr is
Wait until it turns OFF (step 125). In step 124, operate the shutter dial 1 to turn off the time set detection switch SWt, or
When the release button 5 is released and the release switch SWr is turned off in step 125, the motor M starts driving again (step 126).

Due to the motor drive in step 126, the shutter locking member 13 is further displaced in the direction of arrow B in FIG. The engagement is released and the rear curtain 9A is released (step 127).
be done. When the trailing curtain lock is released in this step 126, the trailing curtain magnet Mg ₂ has already stopped excitation and the trailing curtain drive member 15 is not restrained, so the trailing curtain 9B immediately runs (step 128).
and close the shutter. After the shutter is closed, the film is wound through steps 115 and 116 and the shutter is charged (step 117) in the same manner as when the shutter speed is set using the shutter dial 1.
stops, and the operation of the microcomputer 4 is stopped.

When all the films have been shot and the camera back 3 is opened to change the film, the camera back switch SWc, which detects the opening/closing of the 3rd camera back, is turned ON, and the detection signal is sent to the microcomputer 4, which then switches on the camera again. The operation is started and it is determined whether or not the back cover 3 is closed (step 100). When the back cover 3 is opened, it is first determined whether or not the shutter is in the open state based on a signal from the first motor control switch _SW1 (step 130). When the shutter is closed even though the back cover 3 is open, the front curtain 9A is run to protect the shutter curtain, and the shutter is opened next time in order to move it out of the film aperture. It is done by steps.

In other words, the microcomputer 4 switches the back cover switch SWc
ON signal and first motor control switch SW ₁ ON
If it is determined based on the signal that the shutter is not in the open state, a signal is sent to the motor drive control circuit 8.
The motor drive control circuit is activated by this signal from the microcomputer 4 to drive the motor M (step 131).
let The moving member 19 is driven by this motor M.
The shutter locking member 13 is displaced in the direction of arrow B in FIG. 1 through the shutter locking member 13, and the locking of the front curtain drive member 10 that drives the front curtain 9A is released (step 132). At this time, the first curtain magnet Mg ₁ is not excited,
Since the leading curtain drive member 10 is not restrained by the leading curtain magnet _Mg1 , the leading curtain 9A immediately runs (step 133) to bring the shutter into the open state.
Further, when the shutter locking member 13 is slightly displaced, the first motor control switch SW ₁ turns OFF (step 134), and based on that signal, the motor M stops (step 135) until the back cover 3 is closed. In other words, it waits until an OFF signal is input from the back cover switch SWc (step 136).

Furthermore, if it is determined in step 130 that the shutter is in the closed state based on the ON signal of the first motor control switch SW ₁ and the OFF signal of the second motor control switch SW ₂ , the camera back 3 will close. Wait until the In step 136, back cover 3
When the switch is closed, an OFF signal is sent to the microcomputer 4 from the back cover switch SWc. This camera back switch
When receiving the SWc switching signal from ON to OFF,
The ON-to-OFF switching signal of the time set detection switch in step 124 and the step
From turning on the release switch SWr in 125
In the same way as when receiving the switching signal to OFF, the microcomputer 4 drives the motor M (step 126), releases the rear curtain lock (step 127), and immediately runs the rear curtain 9B (128) to start the shutter. Close.
Thereafter, film winding and shutter charging (step 117) are performed via steps 115 and 116, and motor M is stopped (step 118), so that the operation of microcomputer 4 is stopped. Thereafter, normal photographing is performed by pressing the release button 5.

FIG. 3 is a flowchart of the shutter control system for a shutter without the time "T" symbol on the shutter dial, but having a shutter speed scale and valve "B". In this case, only the time set detection switch SWt is removed from the embodiment shown in FIG. 1, and the other configurations are completely the same as in FIG.
In addition, the steps from the flowchart in Figure 2
102, steps 123 and 124 are also deleted, step 106 is inserted between step 105 and step 108, and step 125 is inserted between step 123 and step 126.
Insert as shown. Other steps are second
Since it is exactly the same as that shown in the figure, it is omitted in FIG. That is, in FIG. 3, when the first motor control switch _SW1 is turned off (step 105), it is determined whether the valve set detection switch SWb is turned off (step 6).
When it is OFF, motor M continues to drive, the trailing curtain lock is released (step 108), and further steps are performed.
The shutter is opened and closed between 109 and step 116, and the film is wound and the shutter is charged in step 117. On the other hand, if the valve set detection switch SWb is ON in step 106, that is, if the shutter dial 1 is set to valve "B", the motor M will stop immediately (step 106).
120), and when the excitation of magnets Mg ₁ and Mg ₂ is stopped (step 121), only the leading curtain 9A starts running (step 122). At this point, the camera waits until the release switch SWr is turned OFF, and when it is turned OFF, the motor M is driven again (step 126) and the locking of the rear curtain 9B is mechanically released (step 127).
Then, the rear curtain 9B is immediately moved (step 128) to complete the exposure. Then step 115,
Through step 116, film winding and shutter charging are performed (step 117).

In the above embodiment, the back cover switch SWc
The switch SWc is configured to detect the opening and closing of the back cover 3, and this switch SWc is provided as a shutter curtain protection device when changing the film. Therefore, the switch SWc is operated before opening the back cover 3. It may be configured to turn on in conjunction with the film rewinding operation or the unlocking operation of the back cover 3. Furthermore, it may be configured to also serve as a switch for detecting the presence or absence of film, which detects whether or not the film is present on the film path. Although the length of the leading curtain locking portion 13a of the shutter locking member 13 is formed shorter than that of the trailing curtain locking portion 13b, the lengths of both locking portions 13a and 13b are made equal,
Instead, the length of the claw part 10a of the leading curtain driving member 10 is formed to be shorter than the length of the claw part 15a of the trailing curtain driving member 15, so that even when the leading curtain driving member 10 is unlocked, the trailing curtain driving member 15 The lock may be configured such that it is not yet released.

[Effect of idea]

As described above, according to the present invention, in a shutter control device that controls the leading and trailing shutter curtains using two current-carrying magnets, the two nets are not energized when the back cover is opened, and the trailing curtain is Since only the mechanical locking of the leading curtain driving means is released without releasing the mechanical locking of the driving means, 2
Even in a shutter control device using two current-carrying magnets, the shutter can be opened when the back cover is opened. Further, since a shutter device using an energized attraction type magnet attracts the shutter curtain driving means only when the shutter is controlled and does not perform an attraction operation at other times, dust and the like are less likely to adhere to the attraction surface and scratches are less likely to occur. Therefore, there is an advantage that the accuracy of shutter control is unlikely to deteriorate even if used for a long period of time. Therefore, even when such a shutter is used, the present invention, which allows the shutter to be opened by opening the back cover, is very convenient for the photographer.

[Brief explanation of the drawing]

Fig. 1 is a block diagram showing an embodiment of the present invention, Fig. 2 is a flowchart for explaining the operation of the embodiment shown in Fig. 1, and Fig. 3 is a diagram in which the time set detection switch of Fig. 1 is deleted. 3 is a flowchart showing part of the operation in this case. Explanation of symbols of main parts, {1...shutter dial, 4...microcomputer, 6...front curtain control circuit, 7
... Trailing curtain control circuit, 8 ... Motor drive control circuit,
SWb……Valve set detection switch, SWt……
Time set detection switch} (exposure time control means), 3... Back cover, Mg ₁ , Mg ₂ ... Magnet,
{9A...first curtain, 9B...second curtain} (shutter curtain),
{10... Leading curtain driving member, 15... Trailing curtain driving member}
(shutter curtain driving means), 13... shutter locking member (shutter locking means), 19... moving member (shutter opening means).

Claims (1)

[Scope of Utility Model Registration Claims] A front curtain drive means for driving the front curtain of the shutter; a rear curtain drive means for driving the rear curtain of the shutter; A first energized attraction magnet that prevents the leading shutter curtain from running; and a second energized attraction magnet that is excited by energization and electrically locks the trailing curtain drive means to prevent the shutter trailing curtain from running. a leading curtain control means for controlling energization of the first magnet; a trailing curtain control means for controlling energization of the second magnet; Regardless of the state of the magnet, the first mechanical locking means for preventing the leading shutter curtain from running and the trailing curtain driving means are mechanically locked, and regardless of the state of the second magnet, the and a second mechanical locking means for preventing the shutter trailing curtain from running, and before the shutter release operation, the first and second mechanical locking means are operated by the leading curtain driving means and the trailing curtain driving means. When the shutter release operation is performed, the first and second magnets are excited to electrically lock the leading curtain drive means and the trailing curtain drive means, and when the shutter release operation is performed, the first and second magnets are electrically locked. The mechanical locking of the leading curtain driving means and the trailing curtain driving means by the second mechanical locking means is released, and the mechanical locking of the first and second curtain driving means is released.
A shutter curtain control device for a focal play shutter camera that sequentially releases electrical locking by a magnet and causes a front shutter curtain and a rear shutter curtain to run sequentially, comprising: a detection means for detecting an opening operation of a back cover; in response to operation of the means, said first and second
operating the first mechanical locking means without energizing the magnet and without releasing the mechanical locking of the trailing blade drive means by the second mechanical locking means. 1. A shutter curtain control device comprising: shutter opening/closing control means for releasing only the mechanical locking of the leading curtain driving means by the first mechanical locking means.