JP2975488B2 - Shutter device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shutter device for first setting a distance and then driving a shutter blade.

[0002]

2. Description of the Related Art A shutter device that automatically drives a lens in response to a release signal, sets a photographic lens at a focal position, and then drives a shutter is disclosed in Japanese Unexamined Utility Model Publication No. 3-222.
No. 28. However, in this technique, an opening / closing lever that opens and closes a shutter blade biased in an opening direction is engaged and held by a locking lever, and the shutter is opened by releasing the engagement of the locking lever with a rotating arm of a motor. The locking lever is merely urged in the engagement direction by a spring, and there is a problem that the shutter is opened by an external impact. This problem can be solved by locking the locking lever with another member and retracting the member in response to a release signal, but there is a problem that the number of members increases and the configuration becomes complicated.

[0003]

SUMMARY OF THE INVENTION In view of the above-mentioned circumstances, the present invention provides a shutter lever for opening and closing shutter blades, which is locked at an initial position by a drive pin of an actuator.
A cam surface, and the drive pin connected to the first cam surface
And a second cam surface on which the shutter is driven to open and close by being separated from the cam surface, and the shutter blades are controlled by the shutter lever.

[0004]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the embodiments shown in the drawings. FIG. 1 is a view showing one embodiment of a shutter device according to the present invention in a closed state of the shutter, FIG. 2 is a view showing one embodiment of a shutter device in an open state of the shutter device, and FIG.
FIG. 4 is an embodiment diagram showing an initial state of the focus setting device, and FIG. 4 is an embodiment diagram showing a state after the focus setting of the focus setting device.

The main plate 1b is provided with shutter blades 11a and 11
b are superposed at a predetermined interval to be driven.

In FIG. 3, a shutter base plate 1a has a 2a
An actuator 2 having a drive pin 2b that rotates around the center is provided by a method not shown. In response to the release signal, the drive pin 2b rotates left and returns to the initial position, and then rotates right and returns to the initial position as one cycle. When the drive pin 2b is at the initial position, both ends of the spring 4 provided in FIG. 1 are in contact with the outer periphery of the drive pin 2b.

The locking lever 6, which is urged leftward by a spring 7 about a shaft core 6a, is provided with a surface 6d that comes into contact with the claws 6b, 6c and the drive pin 2b. The rotating ring 8 is provided on the shutter base plate 1a by being urged in the clockwise direction by a spring 9 so that a lens barrel (not shown) rotates following the rotating ring 8. At the initial position, the pawl 6 b of the locking lever 6
And a locking portion 8c that is turned clockwise by a release signal and locked by the claw 6c of the locking lever 6.
And is configured to return to the initial position by rotating leftward in conjunction with film winding.

A photoelectric sensor 10 for detecting the opening and closing of the shutter is provided at the upper right of the shutter base plate 1a. This photoelectric sensor is configured to detect reflected light when shutter blades are present in the detection area.

In FIG. 1, a shutter lever 3 urged in a clockwise direction by a spring 5 around a shaft core 3c is provided on the back surface of the shutter base plate 1b. Pin 3a pierced through the hole 14 and the cam surface 3 in contact with the drive pin 2b
b, 3d are provided. The cam surface 3b is formed as a surface that draws an arc of a fixed distance R from the rotation center of the drive pin 2b at the initial position. The pin 3a of the shutter lever 3 penetrates the elongated holes of the shutter blades 11b, 11a.

The shutter blade 11b is provided with a shutter base plate 1b.
The pin 15a provided as an axis is provided so that the pin 3a is opened by clockwise rotation of the pin 3a about the axis 3c. The shutter blade 11a is provided so as to be opened by a clockwise rotation of the pin 3a around a pin (not shown) provided at a position corresponding to the pin 15 as a rotation center. The opening / closing operation of the shutter blade 11a is detected by the photoelectric sensor 10.

Next, the operation of the shutter device configured as described above will be described. In FIG. 3, the drive pin 2 of the actuator 2 responds to the operation of a release button (not shown).
b rotates counterclockwise to push the cam surface 6d of the locking lever 6, the locking lever 6 rotates clockwise, and the engagement between the pawl 6b and the locking portion 8b of the rotating ring 8 is released. The rotating ring 8 is rotated clockwise by the accumulated force of the spring 9. Following the rotation of the rotating ring 8, the lens barrel (not shown) moves from the initial position toward the focal point, and stops at the focal point. The rotating ring 8 still rotates from the stop position of the lens barrel, but the locking portion 8c of the rotating ring 8 is engaged by the claw 6c of the locking lever 6 and stopped (see FIG. 4). The position of the locking portion 8c of the rotating ring 8 is of course provided at an appropriate position depending on the required maximum movement amount of the lens barrel.

In FIG. 1, even if the drive pin 2b of the actuator 2 rotates counterclockwise, the shutter lever 3 maintains the position shown in FIG. 1 while being in contact with the drive pin 2b. When the lens barrel stops at the in-focus position and the locking portion 8c of the rotating ring 8 is locked by the claw 6c of the locking lever 6 (see FIG. 4), the actuator stopped at the position indicated by the phantom line in FIG. The second drive pin 2b starts rotating clockwise, and further rotates past the position indicated by the solid line.

As a result, the drive pin 2b comes into contact with the cam 3d of the shutter lever 3, and the shutter lever 3 rotates clockwise by the urging force of the spring 5. As a result, the pin 3a is connected to the shutter blades 11a, 11
b is opened (see FIG. 2).

During the shutter opening process, the shutter blades 11a
When the tip of the sensor comes off the photoelectric sensor 10, the photoelectric sensor 10
Sends a shutter opening signal to an electric circuit (not shown).
The exposure time is measured in synchronization with this, and after the appropriate time measurement, the drive pin 2b of the actuator 2 rotates counterclockwise to return to the initial position, and rotates the pin 3a counterclockwise via the cam 3d. The shutter blade 11a is
, The rotation of the drive pin 2b is stopped.

Thereafter, the film is wound up by a mechanism (not shown), and in conjunction with this, the rotating ring 8 rotates counterclockwise and engages with the claw 6b of the locking lever 6 and the locking portion 8b of the rotating ring 8. And return to the initial position.

[0016]

As described above, in the shutter device according to the present invention, the shutter lever for controlling the opening and closing of the shutter blade is locked by the drive pin of the actuator, so that there is no need to provide a special locking lever. With a simple configuration, it is possible to prevent the shutter blade from being opened by a shock.

[Brief description of the drawings]

FIG. 1 is a view showing one embodiment of a shutter device according to the present invention, showing a shutter closed state;

FIG. 2 is an embodiment diagram showing a shutter opened state of the shutter device according to the present invention.

FIG. 3 is an embodiment diagram showing an initial state of the focus setting device.

FIG. 4 is a diagram illustrating an example of a state after the focus is set by the focus setting device.

[Explanation of symbols]

 1a Shutter base plate 1b Shutter base plate 2 Actuator 3 Shutter lever 4 Spring 5 Spring 6 Locking lever 7 Spring 8 Rotating ring 9 Spring 10 Photoelectric sensor 11a Shutter blade 11b Shutter blade 12 pin 13 Lens opening 14 Hole 15 pin

Claims (1)

(57) [Claims] 1. A circular motion is made in one and the other from an initial position,
An actuator having a drive pin for returning to the initial position on the same trajectory; a first cam surface locked by the drive pin when the drive pin is at the initial position and during one circular movement;
A shutter lever having a second cam surface which is provided in continuation with the cam surface and which is driven while the drive pin is moving to the other side and returns to the initial position by the backward movement; A shutter device comprising: a shutter blade that is closed by a shutter blade; and a detection unit that detects opening and closing of the shutter blade.