JP3530212B2 - Camera shutter - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a camera shutter, and more particularly to a camera shutter having an opening shutter blade and a closing shutter blade for shortening an exposure time.

[0002]

2. Description of the Related Art Conventionally known camera shutters open and close an exposure opening by reciprocating a set of shutter blades. However, with this type of shutter, if a large force is applied to the shutter blades to increase the speed during the opening operation in order to shorten the exposure time, the time required for reciprocating switching operation near the fully open position of the shutter blades due to inertia etc. And the closing operation time will inevitably become longer. On the contrary, in order to shorten the closing operation time of the shutter blade, the speed at the opening operation must be reduced. Therefore, there is a limit to shortening the exposure time of this type of shutter.

Therefore, there has been proposed a shutter having an opening shutter blade for opening the exposure opening and a closing shutter blade for closing it. In such a shutter, the opening shutter blade is driven by a dedicated driving mechanism by a dedicated driving mechanism such as a motor, and the closing shutter blade is also driven by a dedicated driving mechanism by a dedicated driving mechanism. ing.

[0004]

However, in this type of shutter, since the opening shutter blade and the closing shutter blade are driven by using separate starting means and separate drive mechanism, the structure becomes complicated, There is a problem that the number of parts increases and the cost increases. In addition, the number of parts increases and the required space also increases, so the size and weight of the camera must be increased. Further, in order to smoothly perform the opening operation and the closing operation in succession, the electric control system has to be complicated, which also causes a cost increase.

The present invention has been made in order to solve such a problem, and it is possible to reduce the number of parts, reduce the size and weight of a camera to be mounted, and reduce the cost. A shutter for use is provided.

[0006]

In order to solve the above-mentioned problems, a camera shutter according to the present invention comprises an exposure opening,
At least one opening shutter blade for performing the opening operation of the exposure opening;
At least one closure shutter blades have been energized perform closing operation of the exposure opening, the operation in the first direction is opened operate the open shutter blade, said by the operation in the second direction A reversible motor for closing the closing shutter blade against the biasing force, the motor performing the opening operation of the opening shutter blade and the closing operation of the closing shutter blade. When the shutter blade for opening is returned to the first initial position where the opening for exposure was closed after being continuously operated and then in the second direction , after that, the shutter blade for closing is opened. However , it is characterized in that it is configured to return to the second initial position which is out of the exposure opening only by the biasing force .

In this case, a driving lever that reciprocates to open and close the opening shutter blade, a regulating means that locks the driving lever at the closing position of the opening shutter blade, and the driving lever in the shutter blade opening direction. It is also possible to provide an urging means for urging, and the regulating means opens the shutter blade for opening by releasing the locking of the drive lever by the motor . Moreover, an eccentric portion which is eccentric to the rotation center of the rotor of the motors provided, when the rotor rotates in the first direction, by the eccentric portion acts to open the shutter blades, the open shutter vane When the opening operation is performed and the rotor is rotated in the second direction opposite to the first direction, the eccentric portion may act on the closing shutter blade to cause the closing shutter blade to perform the closing operation. .

Further, by the operation in the first direction of the motors, after opening shutter blade is opened actuated, by the operation of the second direction of the motor, the closing shutter blade closing operation, for opening The closing shutter blade may return to the second initial position when the shutter blade returns to the first initial position and the motor operates again in the first direction.

In this case , a driving lever that reciprocates to open the opening shutter blade, a restricting means that locks the driving lever at the closing position of the opening shutter blade, and the driving lever in the shutter blade opening direction. Urging means for urging, the restricting means releases the locking of the drive lever by the operation of the motor in the first direction, thereby opening the shutter blades for opening. When the opening shutter blade returns to the first initial position, the driving lever may be locked by the restricting means by the operation of the motor in the second direction.

[0010]

First, the reversible motor operates in the first direction, whereby the opening shutter blade opens the exposure opening to start exposure. After the required exposure time elapses, the motor operates in the second direction, whereby the closing shutter blade closes the exposure opening to complete the exposure. 1 like this
The two motors cause the opening operation of the opening shutter blade and the closing operation of the closing shutter blade to be continuously performed.

[0011] The center of rotation motors of the rotor can be provided an eccentric portion which is eccentric. In this case, when the rotor rotates in the first direction, the eccentric portion acts on the opening shutter blade to open the opening shutter blade. Then, after that, the rotor rotates in the second direction opposite to the first direction, so that the eccentric portion acts on the closing shutter blade to close the closing shutter blade.

It is also possible that the opening shutter blade returns to the first initial position by the operation of the motor in the second direction, and the exposure opening is closed. Furthermore, after this, when the motor operates again in the first direction, the closing shutter blade can be returned to the second initial position so as to be disengaged from the exposure opening.

Further, a driving lever for reciprocating the opening and closing of the shutter blade for opening and closing, a restricting means for locking the driving lever at the closing position of the shutter blade for opening, and a lever for driving in the opening direction of the shutter blade. When the urging means for urging is provided, the restricting means releases the locking of the drive lever by the operation of the motor in the first direction. As a result, the opening shutter blade is opened. When the open shutter blade by the operation of the second direction of the motor is restored to the first initial position, so that the driving lever can be engaged with the regulating means by the operation of the second direction of the motor Become

[0014]

Embodiments of the present invention will be described in detail below with reference to the accompanying drawings. FIG. 1 shows a standby state before starting exposure of a camera shutter according to an embodiment of the present invention. In the figure, reference numeral 1 indicates a shutter base plate, and all the components described below are provided on the shutter base plate 1. A circular exposure opening 2 is formed in the shutter base plate 1.

An iris motor (moving magnet motor) 3 is fixed to the front side of the shutter base plate 1. A shaft (not shown) is provided at the center of the iris motor 3, and the shaft is the shutter base plate 1.
Protruding towards. The shutter base plate 1 is provided with an arcuate slot 4 having a constant central angle. And the eccentric pin 5 is eccentric to the rotation center on the shaft.
The eccentric pin 5 passes through the slot 4 and is regulated so as to rotate within the range of the central angle of the slot 4 and extends to the back side of the shutter base plate 1. In the iris motor 3 in the non-energized state in the standby state shown in FIG. 1, the eccentric pin 5 is stopped at the neutral position in FIG. 1, which is a stationary stable state of the iris motor 3 itself. In addition, it is desirable to elastically bias the eccentric pin 5 by a spring that holds the eccentric pin 5 at a neutral position so as not to swing due to vibration or the like in a non-energized state. For example, a torsion spring is wound around the shaft, one end of which is hooked on the eccentric pin 5, and the other end of which is hooked on a fixed portion such as the shutter base plate 1 to move the eccentric pin 5 in one direction. May be regulated, and a similar torsion spring may regulate the movement of the eccentric pin 5 in the opposite direction. In this case, when the iris motor 3 is energized, the eccentric pin 5 moves against the force of the spring.

A pair of opening shutter blades 6 and 7 are attached to the surface of the shutter base plate 1 so as to be rotatable around support shafts 8 and 9, respectively. Opening shutter blade 6,
7 is a base 1 whose one end is pivotally supported by supporting shafts 8 and 9.
0, 11 and sickle-shaped covers 12, 13 extending laterally from the other ends of the bases 10, 11. In the illustrated standby state, the cover portions 12 and 13 overlap each other, and these cover portions 12 and 13 cooperate to cover the exposure opening 2.

Base 1 of a pair of opening shutter blades 6 and 7
Slots are formed at the ends of 0 and 11 (only the slot 14 of the opening shutter blade 6 is shown in the drawing, and the slot of the opening shutter blade 7 is omitted). These slots overlap each other. Further, a long drive lever 15 is attached to the surface of the shutter base plate 1 so as to be rotatable around a support shaft 16. The drive lever 15 is biased counterclockwise by a spring 17. A pin 18 is provided on the back side of one end of the drive lever 15 so as to project, and the pin 18 is fitted into both of the above slots.

Since the drive lever 15 is biased counterclockwise in this way, the opening shutter blade 6 rotates clockwise from the standby state shown in the drawing, and the opening shutter blade 7 rotates counterclockwise. It rotates so as to open the exposure opening 2. Also, on the surface of the shutter base plate 1,
Pins 20 and 21 that serve as stoppers for this rotating operation of the opening shutter blades 6 and 7 are provided in a protruding manner.

A restricting lever 22 is rotatably mounted on the surface of the shutter base plate 1 about a support shaft 23 provided at one end thereof. The regulating lever 22 is arranged between the above-mentioned shaft (not shown) of the iris motor 3 and the shutter base plate 1. The regulating lever 22 is biased clockwise by a spring 24.
On the surface of the shutter base plate 1, a pin 25 that serves as a stopper for the clockwise rotation of the regulating lever 22 is provided.

The end of the regulating lever 22 opposite to the support shaft 23 is notched, and a stepped locking portion 26 is provided by this. In the standby state shown in the drawing in which the regulating lever 22 is at the limit of rotation in the clockwise direction, the locking portion 26 has the end portion of the driving lever 15 opposite to the pin 18, which is used for driving. The counterclockwise rotation of the lever 15 is restricted, and the drive lever 15 is stationary. Therefore, in this state, since the restricting lever 22 restricts the rotation of the driving lever 15 against the biasing force caused by the spring 17, the opening shutter blades 6 and 7 close the exposure opening 2. ing.

In this standby state, the eccentric pin 5 of the iris motor 3 is in contact with the regulating lever 22 from the right side of the central portion thereof. When the shaft of the iris motor 3 rotates clockwise from this state, the regulating lever 22 moves the eccentric pin 5
It is pressed by and rotates counterclockwise.
As a result, the driving lever 15 is disengaged from the locking portion 26 of the regulating lever 22, the restraint on the driving lever 15 is released, and the opening shutter blades 6 and 7 rotate about the support shafts 8 and 9, respectively. , The exposure opening 2 is opened.

On the back surface of the shutter base plate 1, one closing shutter blade 27 is attached rotatably around a support shaft 28. In the illustrated standby state, the closing shutter blade 27 is located outside the exposure opening 2. In this state, as described above, the eccentric pin 5 of the iris motor 3 penetrating the slot 4 of the shutter base plate 1 is in contact with the side end surface 29 of the closing shutter blade 27 on the support shaft 28 side. When the shaft of the iris motor 3 rotates counterclockwise from this state, the side end surface 29 is pressed by the eccentric pin 5 and rotates clockwise, and the exposure opening 2 is closed.

The closing shutter blade 27 is biased counterclockwise by a spring 30. When the iris motor 3 is de-energized, the exposure opening 2 is closed. It can rotate and return to the initial standby position. Further, on the back surface of the shutter base plate 1, a pin 31 for restricting the counterclockwise rotation of the closing shutter blade 27 is provided.

Next, the operation of the camera shutter of the present embodiment constructed as described above will be described. Figure 1
When the iris motor 3 is energized in the positive direction for exposure and is activated from the standby state shown in (4), its shaft and the eccentric pin 5 rotate clockwise. The eccentric pin 5 presses the regulating lever 22, which causes the regulating lever 22 to rotate counterclockwise against the force of the spring 24. Then, with the rotation of the regulating lever 22, the driving lever 15 is disengaged from the locking portion 26 and the regulation of the counterclockwise rotation is released.

The driving lever 15 is rotated counterclockwise by the force of the spring 17. As a result, the pin 18 fitted in the slot (only 14 is shown) of the opening shutter blades 6 and 7 moves, so that the opening shutter blade 6 is rotated clockwise at the same time as shown in FIG. Rotates counterclockwise to start opening the exposure opening 2. In this way, the opening shutter blades 6 and 7 start the opening operation to start the exposure. After this, the shutter blades 6 and 7 for opening are pin 2 which is a stopper.
It abuts 0 and 21, respectively, and stops its rotation. That is, the exposure opening 2 is fully opened. Then, the eccentric pin 5 reaches the clockwise rotation limit of the slot 4.

When an appropriate exposure time according to the brightness obtained by the photometric means (not shown) has elapsed from the start of exposure,
This time, the iris motor 3 is reversely energized, and its shaft starts rotating counterclockwise. As a result, the eccentric pin 5 rotates counterclockwise, contacts the side end surface 29 of the closing shutter blade 27, and starts pressing the side end surface 29 against the force of the spring 30. And closing shutter blade 27
Rotates clockwise to close the exposure opening 2 as shown in FIG. In this way, the exposure is completed.

After this, the shaft of the iris motor 3 continues to rotate further in the counterclockwise direction, and the eccentric pin 5 moves to the position indicated by the imaginary line which is the counterclockwise rotation limit in the slot 4. During this time, the closing shutter blade 27 also continues to rotate clockwise, but the exposure opening 2 is not opened because the tip of the shutter blade 27 is wide. Further, during this time, the eccentric pin 5 comes into contact with the driving lever 15 and presses it, so that the driving lever 15 rotates clockwise against the force of the spring 17.

As a result, the pin 18 moves clockwise in FIG. 3, so that the opening shutter blade 6 rotates counterclockwise and the opening shutter blade 7 rotates clockwise.
When the eccentric pin 5 reaches the position indicated by the imaginary line,
The restricting lever 22 whose rotation is stopped by the driving lever 15 is rotated clockwise by the force of the spring 24 and comes into contact with the pin 25 as a stopper to stop. With this, similarly to the case shown in FIG. 1, the driving lever 15 is locked to the locking portion 26 of the regulating lever 22. Also, the shutter blade for opening
6 and 7 also return to the initial position shown in FIG. 1 to close the exposure opening 2. Accordingly, the closing shutter blade 27
Regardless of this, the exposure opening 2 is closed.

When the eccentric pin 5 reaches the position of the imaginary line in FIG. 3, the energization of the iris motor 3 is stopped, and the side edges 29 of the closing shutter blade 27 contact the eccentric pin 5 by the force of the spring 30. Rotate counterclockwise while touching. Then, the eccentric pin 5 returns to the initial position shown in FIG. At this time, the closing shutter blade 27 also comes into contact with the pin 31 as a stopper and stops. In this way, one shooting process is completed.

As described above, in the camera shutter of this embodiment, the opening shutter blades 6 and 7 are returned to the initial standby position that covered the exposure opening 2 and closed in one photographing process. The shutter blade 27 for use can be returned to the initial standby position which is out of the exposure opening 2. The eccentric pin 5 also returns to the initial standby position and stops. That is, the camera shutter of the present embodiment is a so-called chargeless type, and it is possible to immediately perform the next shooting without charging when one shooting process is completed. Further, the reason why the two opening shutter blades 6 and 7 are provided as described above is to make it possible to cope with shortening of the exposure time. That is, by covering the exposure opening 2 with the opening shutter blades 6 and 7 in a shared manner, it is possible to shorten the time taken to open the same area as compared with the case where there is one opening shutter blade.

Further, by reversing the rotation direction of the iris motor 3, the opening operation of the opening shutter blades 6 and 7 is switched to the closing operation of the closing shutter blade 27,
Further, the opening shutter blades 6, 7 and the closing shutter blade 27 can be returned to the initial standby position. As a result, even if the rotation angle range of the iris motor 3 is small, not only exposure can be performed but also
Since the next shooting can be performed, it is not necessary to increase the required size of the entire shutter and thus the camera in which the shutter is mounted. Further, the opening operation of the opening shutter blades 6 and 7 is performed by the first clockwise rotation of the iris motor 3, and the closing operation of the closing shutter blade 27 is performed by the counterclockwise rotation thereof. It is possible to separately set the opening time and the closing time of the exposure opening 2 by separately setting the initial rotation speed of 3 and the rotation speed in the counterclockwise direction.

In this embodiment, the exposure opening 2 is fully opened, but the present invention is not limited to this, and in the so-called program AE mode in which the diaphragm is adjusted by the shutter blade, the exposure opening is used for high-luminance photography. 2 may not be fully opened. That is, at a proper time while the driving lever 15 is disengaged from the locking portion 26 and the opening shutter blades 6 and 7 are being opened, the iris motor 3 is reversely energized to move the eccentric pin 5 counterclockwise. The shutter blade 27 for closing is closed by rotating the shutter blade 27. Therefore, the exposure opening 2 can be closed when the opening shutter blades 6 and 7 have the desired aperture diameters.

[0033]

As is apparent from the above description, according to the first aspect of the present invention, the exposure shutter blade and the closing shutter blade are linked by only one reversible motor for exposure control. Therefore, it is possible to reduce the number of parts, reduce the size and weight of the camera to be mounted, and reduce the cost. Further, since the opening direction of the opening shutter blade is switched to the closing operation of the closing shutter blade by reversing the operation direction of the motor, even if the operation process of the motor is short, the entire shutter and hence the camera in which the shutter is mounted are mounted. There is no need to increase the required size. Further , the opening operation of the opening shutter blade is performed by the operation of the motor in the first direction,
Since the closing operation of the closing shutter blade is performed by the operation in the direction of, the operation speed of the motor in the first direction and the operation speed in the second direction are separately set, so that the exposure opening It is possible to set the opening time and the closing time separately. In addition, the operation of one motor
The shutter blade for opening returns to the first initial position and closes
Shutter blade returns to the second initial position,
It is possible to make the shutter blade a chargeless type
It As a result, after performing the exposure operation,
It is possible to wait for the exposure startable state.

According to the second aspect of the invention, since the opening shutter blade can be opened with a simple structure, the effect of reducing the number of parts can be enhanced.

Further, according to the invention described in claim 3,
Since the opening shutter blade can be opened by the eccentric portion provided on the rotor of the motor, the effect of reducing the number of parts can be enhanced.

[0036] According to the invention described in claim 4, Mo
Movement of the shutter in the second direction causes closing shutter blades.
Closing operation and opening shutter blade to the first initial position
Since the return operation is performed, the configuration becomes more preferable.

Further, according to the invention described in claim 5 , in addition to the same effect as the invention described in claim 1 , it is possible to obtain the same effect as the invention described in claim 2.

[Brief description of drawings]

FIG. 1 is a plan view showing a standby state before starting exposure of a camera shutter according to an embodiment of the present invention.

FIG. 2 is a plan view showing a state of the camera shutter during exposure.

FIG. 3 is a plan view showing an exposure end state of the camera shutter.

[Explanation of symbols]

1 Shutter base plate 2 Aperture for exposure 3 Iris motor 5 eccentric pin 6,7 Opening blade 15 Drive lever 22 Regulator lever 27 Closing blade

Claims (5)

(57) [Claims] 1. An exposure opening, at least one opening shutter blade for opening the exposure opening, and
Have been biased in a direction out of the exposure opening and at least one closure shutter blade performs closing operation of the exposure opening, the operation in the first direction is opened operate the open shutter blade, the By the movement in the direction of 2 above
A reversible motor for closing the closing shutter blade against the biasing force, the motor performing the opening operation of the opening shutter blade and the closing operation of the closing shutter blade. after continuously carried out, further
When the shutter blade is moved in the second direction, the opening shutter blade returns to the first initial position in which the exposure opening was closed, and thereafter, the closing shutter blade is pressed by the biasing member.
A shutter for a camera, wherein the shutter is returned to a second initial position which is out of the exposure opening only by force . 2. A drive lever that reciprocates to open and close the opening shutter blade, and a restricting means that locks the driving lever at the closing position of the opening shutter blade.
Urging means for urging the drive lever in the shutter blade opening direction, and the restricting means releases the locking of the drive lever by the motor to open the opening shutter blade. The shutter for a camera according to claim 1, wherein the shutter is as described above. 3. The rotor of the motor is provided with an eccentric portion which is eccentric with respect to the center of rotation, and the eccentric portion acts on the opening shutter blade when the rotor rotates in the first direction. As a result, when the opening shutter blade is opened and the rotor rotates in the second direction opposite to the first direction, the eccentric portion acts on the closing shutter blade, The camera shutter according to claim 1 or 2, wherein the closing shutter blade is adapted to perform a closing operation. 4. The operation of the motor in the first direction causes the opening shutter blade to open, and the operation of the motor in the second direction causes the closing shutter blade to close. The opening shutter blade returns to the first initial position, and when the motor operates again in the first direction, the closing shutter blade returns to the second initial position. The camera shutter according to claim 1 , wherein: 5. A drive lever that reciprocates to open the opening shutter blade, and a restricting unit that locks the driving lever at the closing position of the opening shutter blade.
Urging means for urging the drive lever in the shutter blade opening direction, wherein the restricting means releases the lock of the drive lever by the operation of the motor in the first direction,
The opening shutter blade is operated to open, and when the opening shutter blade returns to the first initial position, the driving lever causes the driving lever to move in the second direction by the operation of the motor. The camera shutter according to claim 4 , wherein the shutter is locked by the restricting means.