JP2002202544A - Digital camera shutter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a digital camera shutter capable of selectively performing large-aperture photographing and small-aperture photographing only by the reciprocating rotation of a motor in one way. SOLUTION: The driving pin 7a of a rotor 7 is fitted into the oblong holes of shutter blades 14 and 15, a control member 11 is rotated clockwise by a spring 12, a diaphragm member 16 is brought into contact with a stopper 1q by connecting a pin 11d and an oblong hole 16b. The pin 11d can get over one end of a spring 13. In the case of photographing through the aperture part 1a, the rotor 7 is rotated at low voltage and current, and then, the driving pin 7a is moved backward from a position in contact with the arm part 11a of the control member 11. In the case of photographing through the aperture part 16a, the rotor 7 is rotated at high voltage and current, the arm part 11a of the control member 11 is pressed so as to move the pin 11d from an initial position toward the opposite side of one end of the spring 13, and at the time of moving backward, the pin 11d is returned to the initial position by the edge of the window part 15a of the shutter blade 15.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention includes an aperture member having an aperture having a diameter smaller than the exposure aperture, and enables photographing by selecting one of the aperture and the exposure aperture. And a digital camera shutter.

[0002]

2. Description of the Related Art A recent camera has been increasingly electrified. In the case of a so-called lens shutter,
The number of shutter blades that are opened and closed only by a motor has been increasing. In particular, almost all shutters used in digital cameras have adopted such a configuration. Also, in the case of a digital camera, a shutter having an aperture mechanism is sometimes employed. In such a case, since a large number of aperture openings having different apertures are rarely required, a shutter having a smaller aperture than the exposure aperture is required. Many devices having a diaphragm member having only one opening are used. It is also required that such a throttle member be operated by a motor. Under such circumstances, an example in which both the shutter blades and the aperture member are operated only by a motor is disclosed in Japanese Patent Application Laid-Open No. 200-200200.
No. 0-60088.

[0003]

However, even with this type of shutter, there is an extremely large demand for cost reduction. For this reason, we have made every effort to reduce the number of parts, use plastics for parts, and share parts, etc., but occupy a large weight in cost. Is the motor. In addition, as described in the above-mentioned publication, when the motor for operating the shutter blades and the motor for operating the aperture member are separately provided as described in the above-mentioned publication, consideration must be given to cost reduction in manufacturing. However, there is a limit to this, and it cannot be said that it is sufficiently satisfactory from the viewpoint of reducing the size of the shutter, and there is still room for improvement.

Therefore, it is conceivable that one motor operates both the shutter blades and the aperture member. As a method for making such a case possible, a configuration is adopted in which the motor is reciprocated in both directions from a predetermined initial position, and when photographing with a small aperture, the motor moves forward in one direction. Then, set the aperture member, return to the initial position once, start shooting, and at the end of shooting, rotate the motor in the opposite direction from the initial position to close the shutter blades and store the image signal in the memory. After the transfer, it is returned to the initial position, then rotated again in the above-mentioned direction to release the set state of the aperture member, and finally returned to the initial position to prepare for the next photographing. It is possible. However, in such a case, the motor is reciprocated three times from the initial position, and the control of the motor becomes troublesome.
There is a problem that the time until the motor finally returns to the initial position becomes longer, and the timing of performing the next photographing is delayed.

The present invention has been made to solve such a problem.
This is a so-called lens shutter in which a plurality of shutter blades are simultaneously operated in opposite directions to open and close a circular exposure opening. By simply reciprocating one motor from an initial position in one direction, the exposure opening can be adjusted. An object of the present invention is to provide a shutter for a digital camera capable of performing photographing with a small aperture and photographing with a small aperture member.

[0006]

In order to achieve the above object, a digital camera shutter according to the present invention comprises a motor in which the rotation direction of a rotor can be changed according to an energizing direction and an applied voltage can be switched. A driving unit that is reciprocated from an initial position by a motor, and at least one shutter that opens a circular exposure opening when the driving unit is in the initial position and is reciprocated in conjunction with the reciprocating operation of the driving unit. The blade is biased by a spring and is normally positioned by a predetermined stopper, and when a low voltage is applied to the motor, the forward movement of the driving unit from the initial position is stopped halfway, and the exposure by the shutter blade is performed. When a high voltage is applied to the motor while maintaining the closed state of the opening, the urging force of the spring is caused by the forward movement of the driving means from the initial position. A control member which is actuated anti to,
An aperture member having an opening with a smaller diameter than the exposure opening, and being actuated from an initial position when the control member is operated against the biasing force of the spring, and inserting the opening into the exposure opening; Holding means for holding the opening inserted into the exposure opening when the diaphragm member is operated from its initial position, and releasing the holding when the driving means is moved back. I do.

In the digital camera shutter according to the present invention, when a high voltage is applied to the motor,
The shutter blade closes and reopens the exposure opening once by the forward movement of the driving means from the initial position, and closes and reopens the opening by returning the driving means to the initial position. It may be.

Further, in the digital camera shutter according to the present invention, the control member and the aperture member are fitted and connected by a pin and a long hole, the holding means is a spring, and the driving means is When the control member is operated in the forward movement from the initial position, the pin is moved from one end of the spring to the other after bending one end of the spring, and the position after the movement is changed. When the aperture member is held in a state in which the aperture is inserted into the exposure aperture by being brought into contact with the one end, a configuration advantageous in cost is obtained.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to the embodiments shown in FIGS. FIG. 1 is a plan view of the initial state of the embodiment viewed from the subject side. FIG. 2 is an exploded cross-sectional view of a main part viewed from substantially the left side of FIG. 1. The upper part of the drawing is the image sensor side, and the lower part is the subject side. 3 to 7 are plan views of the embodiment viewed in the same manner as FIG. 1, and show different operation states. Further, in each plan view, three plate members constituting the shutter chamber and the diaphragm chamber are not shown, but those plate members are shown in FIG.

First, the configuration of this embodiment will be described mainly with reference to FIGS. As shown in FIG. 2, the shutter of this embodiment includes a shutter base plate 1, an intermediate plate 2, and an auxiliary base plate 3.
Are attached to each other at predetermined intervals by means not shown, and in a state of being incorporated in the camera, the auxiliary base plate 3 is arranged with the subject side.
The space between the shutter base plate 1 and the intermediate plate 2 is
A shutter chamber in which a plurality of shutter blades are arranged, and a space between the intermediate plate 2 and the auxiliary base plate 3 is a diaphragm chamber in which a diaphragm member described later is disposed. However, those shutter blades and the aperture member are shown in FIG. 1 but are omitted in FIG. 2, and the shutter base plate 1, the intermediate plate 2, and the auxiliary base plate 3 are omitted in FIG. Further, the shutter base plate 1, the intermediate plate 2, and the auxiliary base plate 3 are formed with a circular opening serving as an optical path of the subject light. In this embodiment, the shutter base plate for regulating the exposure opening (maximum diameter) is used. Only one opening 1a is shown in FIG.

On the image pickup element side of the shutter base plate 1, that is, on the rear side in FIG. 1, it is called a moving magnet type motor of a current control type capable of rotating the rotor back and forth only within a predetermined angle range. Motor is installed. This motor is well known, and several types of configurations are known (for example, those described in JP-A-2000-66267 and JP-A-2000-78808). In the present embodiment, as shown in FIG. 2, the base frame 4 of this type of motor is
The holes formed therein are fitted to shafts 1b and 1c formed in the shutter base plate 1, and are fixed by a plurality of screws 5 (only one is shown). The base frame 4 has a cover frame 6 having a cylindrical flower pot inverted.
Is attached by the hook portion 6a.

A rotor 7 is disposed in a hollow portion of the cover frame 6 and is supported by the base frame 4 and the cover frame 6. The rotor 7 is made of a two-pole permanent magnet that is magnetized in the radial direction. In the case of this embodiment, the rotating shaft and the portion that protrudes in the radial direction are made of synthetic resin. A cylindrical drive pin 7a is formed at the protruding portion. The drive pin 7a has a similar shape formed in the shutter base plate 1, the intermediate plate 2, and the auxiliary base plate 3 when the planar shape formed in the base frame 4 is inserted into the arc-shaped long hole 4a. It is also inserted into the long holes 1d, 2a, 3a.

A coil 8 is wound around a stator frame constituted by the base frame 4 and the cover frame 6 so as to cover two bearing portions of the rotor 7. Further, the cover frame 6 includes
As is well known, the long grooves 6b are formed at a plurality of positions, and the iron pins 9 are press-fitted into each of them. FIG. 2 shows only one of them. A cylindrical yoke 10 is fitted and fixed to the outer peripheral surface of the cover frame 6. In FIG. 1, only the rotor 7 of the motor having such a configuration is shown, the drive pins 7a are shown by solid lines, and the others are shown by two-dot chain lines.

A control member 1 is mounted on the shaft 1c of the shutter base plate 1.
1 is rotatably mounted. This control member 11
As can be seen from FIG. 1, the two arms 11a and 11b
The arm portion 11a is provided with a spring hook portion 11c, and the arm portion 11b is provided with a pin 11d. As shown in FIG.
1b. And the shutter base plate 1
The pin 11d erected on the side penetrates a long hole 1e formed in the shutter base plate 1 in an arc shape in plan view, and a long hole 2b of the intermediate plate 2 formed in the same shape, and a length of the auxiliary base plate 3 Hole 3
b. A spring 12 is loosely wound around the bearing cylinder of the control member 11, one end of which is hooked on the spring hook 1f of the shutter base plate 1, and the other end of which is hooked on the spring hook 11c. This biases the control member 11 to rotate clockwise in FIG.

A shaft 1g is provided on the surface of the shutter base plate 1 on the cover frame 4 side. On the same surface of the shutter base plate 1, spring hooks 1h, 1i, 1j are provided. A spring 13 is wound around the shaft 1g, and one end of the spring 13 is sandwiched between the spring hooks 1h and 1i.
The other end is hung on the spring hook 1j. In addition, the other end faces the operation trajectory of the pin 11d erected on the cover frame 4 side of the control member 11, and is pushed by the pin 11d as understood from the operation description to be described later. In FIG. 1, it is bent to the right and to the left.

Two shutter blades 14 and 15 are arranged in a shutter chamber formed between the shutter base plate 1 and the intermediate plate 2. The shutter blades 14 disposed on the shutter base plate 1 side are connected to the shaft 1 provided on the shutter base plate 1.
The shutter blade 15 rotatably mounted on the intermediate plate 2 and mounted on the intermediate plate 2 side includes a shaft 1 provided on the shutter base plate 1.
The drive pin 7a is rotatably mounted on the shutter blades 14 and 15 and is fitted in a well-known long hole formed in both of the shutter blades 14 and 15. In addition, both shutter blades 1
Window portions 14a and 15a are formed in the windows 4 and 15, respectively.
A pin 11d erected on the shutter base plate 1 side of the control member 11 is inserted into the window 15a.
However, the other window 14a has no function. The only difference is that the two shutter blades 14 and 15 are made into a common component. Further, the shutter bottom plate 1 has two stoppers 1n, 1 for the operation of the shutter blades 14.
p is provided.

The shaft 1m on which the shutter blades 15 are mounted in the shutter chamber is composed of the intermediate plate 2 and the auxiliary base plate 3.
It extends into the squeezing chamber formed between them. And
A diaphragm member 16 is disposed in the diaphragm chamber, and the shaft 1
m so as to be rotatable. Also, the aperture member 1
6 has an opening 16a and an elongated hole 16b having a smaller diameter than the opening 1a. The elongated hole 16b is provided with a pin 11d standing upright on the shutter base plate 1 side of the control member 11.
Are fitted. The shutter base plate 1 is provided with a stopper 1q for the diaphragm member 16.

Next, the operation of this embodiment will be described. FIG.
Indicates an initial state of the present embodiment, that is, a state in which the power switch of the camera is in an on state, but no photographing is being performed. At this time, since the shutter blades 14 and 15 fully open the opening 1a, the subject light transmitted through the photographing lens reaches the image sensor.
The subject image can be observed on a monitor. At this time, since the urging force of the spring 12 acts to rotate the control member 11 clockwise, the restricting member 16 also rotates clockwise due to the connection between the pin 11d and the elongated hole 16b. However, the rotation is blocked by the stopper 1q, and the state of being retracted from the opening 1a is maintained.

On the other hand, at this time, the coil 8 of the moving magnet type motor is not energized. However, a rotational force in the counterclockwise direction in FIG. 1 is applied to the rotor 7, and the shutter blade 14
n, and the fully opened state of the opening 1a is maintained. In addition, the reason why the rotating force is applied to the rotor 7 in the non-energized state is that the permanent magnet of the rotor 7 is located between the iron pins 9 and the rotor 7. The specific structure for obtaining such a function is disclosed in Japanese Patent Application Laid-Open No. 2000-662.
No. 67 and Japanese Patent Application Laid-Open No. 2000-78808 are well-known and will not be described here.
In this embodiment, the iron pin 9 is provided for the purpose of simply maintaining the state of FIG. 1 in the non-energized state.
Only one iron pin 9 may be used. And that is also well known.

When the release button is pressed at the time of photographing, it is possible to select, depending on the brightness of the subject light, whether to photograph through the large-diameter opening 1a or the small-diameter opening 16a. Therefore, first, a case in which a large aperture is selected for photographing will be described. In this case, the electric charge of the image sensor is immediately released to start photographing. Then, when an exposure end signal is output, a low voltage current is supplied to the coil 8 in the positive direction. Therefore, the rotor 7 rotates clockwise,
The shutter blades 14 and 15 are moved to the axis 1 by the drive pin 7a.
Rotation is performed at k and 1 m to close the opening 1a. Then, the closing operation is stopped when the drive pin 7a contacts the arm 11a of the control member 11. Because the spring 12
Is greater than the rotational force of the rotor 7.
FIG. 3 shows a state in which the opening 1a is closed and the opening 1a is closed.

When the imaging signal is transferred to the memory in the closed state, a low voltage current is supplied to the coil 8 in the reverse direction. For this reason, the rotor 7 is
Then, the shutter blades 14 and 15 are rotated in the opposite direction by the drive pin 7a to open the opening 1a. Then, such an opening operation is stopped by the shutter blade 14 abutting on the stopper 1n, and thereafter, the power supply to the coil 8 is cut off, and the initial state shown in FIG. 1 is obtained. Therefore, the subject image can be observed on the monitor, and the next photographing can be performed immediately.

Next, a case in which a small aperture is selected for photographing will be described. In that case, first, a high voltage current is supplied to the coil 8 in the positive direction. Therefore, as in the case described above, the rotor 7 rotates clockwise, the shutter blades 14 and 15 are rotated by the drive pin 7a, and the opening 1a is closed, and the state shown in FIG. 3 is obtained. However, in this case, since a high voltage is applied to the coil 8, the rotor 7 does not stop in this state, and the driving pin 7a pushes the arm 11a of the control member 11, and the spring 12 is attached. The control member 11 is rotated counterclockwise against the force. Therefore, the aperture member 16 is also provided with the control member 11 in its long hole 16b.
The pin 11d is rotated counterclockwise. FIG. 4 shows a state in which the pin 11 d contacts one end of the spring 13. In this state, the opening 1 a is still closed by the shutter blades 14 and 15.

When the rotor 7 is further rotated from the state shown in FIG. 4, the pin 11d of the control member 11 causes one end of the spring 13 to bend. 4 returns to the posture shown in FIG. 4 due to its own elasticity. Immediately thereafter, the shutter blades 14 abut against the stopper 1p, and the clockwise rotation of the rotor 7 is stopped. In the stopped state, as shown in FIG. 5, the center of the opening 16a of the aperture member 16 is a position overrunning the center of the opening 1a.

Here, in the case of this embodiment, an optical sensor (not shown) for detecting that the shutter blade 14 is at the contact position with the stopper 1p is arranged.
When the detection signal is turned on, the voltage applied to the coil 8 is switched from a high voltage to a low voltage. However, the current supply direction remains unchanged without changing the direction. Therefore, the biasing force of the spring 12 exceeds the rotating force of the rotor 7,
The control member 11 rotates clockwise. At this time, the control member 11 rotates the rotor 7 in the counterclockwise direction and rotates the diaphragm member 16 in the clockwise direction. The rotation of the rotor 7 also rotates the shutter blades 14 and 15, When the shutter blade 14 separates from the stopper 1p, the optical sensor is turned off.

The rotation of each member performed in this manner is stopped when the pin 11d of the control member 11 contacts one end of the spring 13. This is because the biasing force of the spring 12 is superior to the rotating force of the rotor 7, but is inferior to the sum of the rotating force of the rotor 7 and the biasing force of the spring 13. FIG. 6 shows a state in which the shutter 16 is stopped in such a manner. In the diaphragm member 16, the center of the opening 16a coincides with the center of the opening 1a, and the shutter blades 14, 15
Opens the opening 16a. Then, after a predetermined time from the OFF signal of the optical sensor described above, the charge of the image sensor up to that time is released, and shooting is started.

Thereafter, when an exposure end signal is output, a low voltage current is supplied to the coil 8 in the reverse direction, and the rotor 7 is rotated counterclockwise. At this time, the control member 11 also attempts to rotate the arm 11a in the clockwise direction by following the drive pin 7a, but the biasing force of the spring 12 does not allow one end of the spring 13 to be bent by the pin 11d. , Can not rotate. Therefore, the aperture member 16
5 is maintained in the position shown in FIG. 5, the rotor 7 is rotated counterclockwise, and the shutter blades 14, 15 once close the opening 16a and then open. Then, during the closing, the imaging signal is transferred to the memory and the opening 1
After opening 6a, the window 15a of the shutter blade 15
The state where the edge is brought into contact with the pin 11d is the state shown in FIG.

In the state shown in FIG. 7, since the sum of the urging force of the spring 12 and the rotational force of the rotor 7 acts on the pin 11d, the force exceeds the urging force of the spring 13. As a result, the pin 11d bends one end of the spring 13, and at the same time rotates the aperture member 16 clockwise. Then, when the pin 11d passes over one end of the spring 13, the one end returns to the posture of FIG. 6 due to its own elasticity, but immediately thereafter, the shutter blade 14 contacts the stopper 1n,
The aperture member 16 comes into contact with the stopper 1q, and the clockwise rotation of the rotor 7 is stopped. Thereafter, the power supply to the coil 8 is cut off, and the initial state shown in FIG.

In the above embodiment, the driving pin 7
a has been described as being integral with the rotor 7 of the moving magnet type motor.
Lever (usually,
And the drive source is not limited to the moving magnet type motor, and may be a step motor.

[0029]

As described above, the shutter for a digital camera according to the present invention is a so-called lens shutter in which two shutter blades simultaneously operate in opposite directions to open and close a circular exposure opening. By simply reciprocating one motor in one direction from the initial position, it is possible to take a picture with a large aperture by the exposure aperture or a picture with a small aperture member. Not only is it very advantageous for miniaturization, but also has a feature that the rotation control of the motor is simplified and a series of operation times can be shortened.

[Brief description of the drawings]

FIG. 1 is a plan view of an initial state of an embodiment viewed from a subject side.

FIG. 2 is a sectional view of a main part viewed from substantially the left side of FIG. 1,
The lower side of the drawing is the subject side.

FIG. 3 is a plan view of the embodiment viewed in the same manner as FIG. 1, and shows a state immediately after the end of exposure when photographing with a large aperture.

FIG. 4 is a plan view of the embodiment as viewed in the same manner as in FIG. 1, showing a state where the aperture member has begun to be operated when photographing with a small aperture;

FIG. 5 is a plan view of the embodiment viewed in the same manner as FIG. 1, and shows a state where the aperture member has overrun the set position when photographing with a small aperture.

FIG. 6 is a plan view of the embodiment viewed in the same manner as FIG. 1, and shows a state in which setting of a small aperture by a diaphragm member is completed.

FIG. 7 is a plan view of the embodiment viewed in the same manner as FIG. 1 and shows a state immediately before the shooting with the small aperture is completed and the setting state of the small aperture by the aperture member is released. is there.

[Explanation of symbols]

1 Shutter base plate 1a, 16a Opening 1b, 1c, 1g, 1k, 1m Axis 1d, 1e, 2a, 2b, 3a, 3b, 4a, 16b
Slot 1n, 1p, 1q Stopper 1f, 1h, 1i, 1j, 11c Spring hook 2 Intermediate plate 3 Auxiliary base plate 4 Base frame 5 Screw 6 Cover frame 6a Hook 6b Long groove 7 Rotor 7a Drive pin 8 Coil 9 Iron pin DESCRIPTION OF SYMBOLS 10 Yoke 11 Control member 11a, 11b Arm 11d Pin 12, 13 Spring 14, 15 Shutter blade 14a, 15a Window 16 Stopper member

Claims (3)

[Claims] 1. A motor in which the rotation direction of a rotor can be changed according to an energizing direction and an applied voltage can be switched, a driving unit reciprocated from an initial position by the motor, and when the driving unit is in an initial position. Has a circular exposure opening, at least one shutter blade which is reciprocated in conjunction with the reciprocating operation of the driving means, and which is biased by a spring and is normally positioned by a predetermined stopper. When the voltage is applied, the forward movement of the driving means from the initial position is stopped halfway, the closed state of the exposure opening by the shutter blade is maintained, and when the high voltage is applied to the motor, the driving means A control member actuated against the urging force of the spring by the forward movement from the initial position; and a control member having an opening having a diameter smaller than the exposure opening. A diaphragm member which is actuated from an initial position when the control member is acted against the urging force of the spring and inserts the opening into the exposure opening; and an aperture when the diaphragm member is actuated from the initial position. And a holding means for holding the portion inserted in the exposure opening and releasing the holding when the driving means moves backward. 2. When a high voltage is applied to the motor, the shutter blade temporarily closes and then reopens the exposure aperture due to the forward movement of the driving means from an initial position, and the shutter blades are initially opened. 2. The digital camera shutter according to claim 1, wherein the opening is closed and then opened again by returning to the position. 3. The control member and the throttle member are fitted and connected by a pin and a long hole, and the holding means is a spring, and the control member is moved forward from an initial position of the driving means. When is operated, the pin is moved from one end of the spring to the other after bending the one end of the spring, and the position after the movement is brought into contact with the one end, 3. The shutter according to claim 1, wherein the aperture member is held in a state where the opening is inserted into the exposure opening.