JPH0610354Y2 - Rear drive activation control device for motor drive cameras - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a rear curtain activation control device for a single-lens reflex camera with a built-in motor drive mechanism.

A single-lens reflex camera with a built-in motor in the camera body has been proposed, in which the motor rotates in the forward direction to narrow down the mirror to raise the mirror, and the rotation in the opposite direction causes the mirror to descend, the shutter charge, and the film to be fed. , Already implemented.

In such a motor drive camera, various mechanisms are driven by forward and reverse rotations of the motor by an electric control signal, but the control system is complicated because the motor is used for many purposes.

The inventor of the present invention pays attention to using the forward / reverse rotation of the motor as a mechanical control signal, and uses the mechanical signal of the forward / reverse rotation of the motor as a signal for setting / resetting the starting mechanism of the rear curtain. I tried to simplify it.

An object of the present invention is to provide a rear curtain activation control device for a motor drive camera that can be reliably controlled with a simple mechanism.

The configuration of the rear curtain activation control device for the motor drive camera according to the present invention to achieve the above object will be described below in association with the embodiment.

That is, the rear curtain activation control device of the motor drive camera according to the present invention has an electromagnetic shutter and is rotated in the first direction at the time of shutter release.
In a rear curtain activation control device for a motor drive camera using a motor that can be rotated in the direction of, a screw 20 that has a spiral groove on the outer periphery and that is connected to a first gear 2 that rotates in the forward and reverse directions by receiving rotational force from the motor. A one-rotation eccentric cam 35 connected to a second gear that rotates from the first gear 2 through a one-way clutch; and a trailing gear that transmits the rotational force for the shutter curtain set from the second gear. A rear curtain cam 32, a screw 20, a one-rotation eccentric cam 35, and a rotation shaft center in a triangle that forms a center between the shafts of the trailing blade gears. A first extending portion extending between the rotary shaft center and having a movable piece 28 at a tip thereof; Biasing force in the direction of contact Support lever 25 having a second extending portion 36 which Gill
And is pivoted coaxially with the support lever 25, extends between the one-rotation eccentric cam 35 and the trailing blade gear, and abuts a portion of the supporting lever 25 to apply the biasing force to the trailing blade cam. 32
A trailing blade start lever 30 that locks the movable piece 28, an electromagnet 27 that adsorbs and holds the movable piece 28 against the biasing force of a support lever 25 that supports the movable piece 28, the electromagnet 27 and the one-rotation eccentric cam. In between, the hook lever 23 is biased and pivoted so that the hook portion moves in a direction orthogonal to the plane of rotation of the support lever 25 to lock the support lever 25, and the hook lever 23. And a signal lever 21 that is coaxially pivoted, follows the rotation of the screw 20, and releases the lock of the support lever 25 against the biasing force of the hook lever 23, in synchronization with the release signal. , The screw rotates forward to unlock the support lever by the hook lever, reversely rotates the screw in synchronization with winding of the shutter, and the hook lever engages the support lever. The one-rotation eccentric cam drives the second extending portion 36 of the support lever to engage the hook lever, and the trailing blade start lever 30 engages the trailing blade cam 32. It is configured to stop and lock the trailing blade gear in place.

Hereinafter, the present invention will be described in more detail with reference to the drawings.
FIG. 1 is a perspective view showing an embodiment of a control device according to the present invention together with the overall configuration of a motor drive mechanism of a single-lens reflex camera, and FIG. 2 is an enlarged perspective view showing an embodiment of the control device according to the present invention. FIG. 1 and FIG. 2 both show the state in which the shutter charge is completed.

When a release button (not shown) is pressed, the motor 1 rotates in the direction shown in FIG. 1a, and the ratchet gear 3 rotates counterclockwise via the reduction gear train. The ratchet arm 4 engaging with the ratchet gear 3 drives the mirror drive lever 5 and the diaphragm lever 6 in the clockwise direction against the diaphragm restoring spring 7. In conjunction with this, the Mirror Atsprever 15
Rotating counterclockwise, the tip of the lever 15 pushes up the mirror roller and the mirror starts to move up.

Simultaneously with this operation, the control mechanism according to the present invention operates in synchronization with the release button. That is, since the rotation in the a direction is similarly given from the upper shaft of the motor 1, the rotation of the motor 1 is performed by the gear 17 and the shock absorbing friction gear.
Since it is transmitted to the gear 2 having the one-way clutch via 18, the rotation of the motor in the a direction is not transmitted to the gear train after the gear 2.

As shown in detail in FIG.
The rotation in the a direction causes the rotation in the a'direction in FIG. The tip end of the signal lever 21 inserted in the groove of the screw 20 is guided by the spiral groove of the screw 20 by the rotation of the screw 20 in the a'direction, and descends. Here, the spring 34 biases one end to rotate the signal lever 21 clockwise and the other end to rotate the hook lever 23 counterclockwise, and therefore does not normally contribute to the movement of the signal lever 21. , The signal lever 21 and the hook lever 23 are clamped together, and the spring 24 urges the hook lever 23 counterclockwise so that the signal lever is integrated.
21 is urged upward, and the tip of the signal lever 21
Guided to the underside of 20 spiral grooves. When the screw 20 rotates in the a'direction and the signal lever 21 descends, the signal lever 21 pushes the bent portion 22 of the hook lever 23, and the hook lever 23 descends against the urging force of the spring 24. Therefore, the movable piece supporting lever 25 of the magnet is released from the restraint, but the movable piece 28 is attracted to the restoring force of the spring 26 by the attraction force of the magnet 27 in FIG. The lever 25 does not rotate counterclockwise.

Next, as the above-mentioned mirror drive progresses, the tip of the mirror lever 15 pushes the hook 16 of the trigger lever 8 just before the mirror rises, the trigger lever 8 is released from the constraint, and it rotates clockwise to move the front curtain. Hit the start lever 29 to start the first curtain of the shatter. After that, when the shutter magnet 27 turns off after the set shutter time, the movable piece 28
The support lever 25 rotates counterclockwise according to the restoring force of the spring 26, and pushes the pin 31 planted on the trailing blade start lever 30. The trailing blade start lever 30 is released from the trailing blade cam 32 and released from the restraint, so that the trailing blade starts, the shutter is closed, and the shutter operation is completed.

When the shutter operation is completed, the winding operation is started. At the time of hoisting, the motor 1 rotates in the reverse direction, that is, in the direction shown in FIG. 1b, and the ratchet gear 3 rotates clockwise this time. Therefore, the constraint of the mirror drive lever 5 is released and the mirror is restored. As a result, the mirror is restored, and the aperture lever 6 is restored according to the biasing force of the spring 7. The motor 1 continues to rotate even after the mirror and diaphragm are restored, but the ratchet arm 4 slips against the ratchet gear 3. During this rotation, the cam 16 of the intermediate gear keeps the trigger lever 8 in the holding state and the hook 16
Lock with.

On the other hand, the rotation of the motor 1 in the b direction is transmitted to the shaft above the motor 1 from the gear 17 to the gear 18 and then to the one-way clutch gear 2, but this time because the clutch meshes, the gear 2
It is also transmitted to the subsequent gears to transmit the power for feeding the shutter charge and the film. Since the gear 19 meshing with the one-way clutch gear 2 rotates in the b'direction as shown in FIG. 2, the rotation of the screw 20 in the b'direction causes the signal lever 21 to be guided in the spiral groove of the screw 20 and start to move up. ,
Following this, the hook lever 23 also rises. However, since the movable piece support lever 25 of the magnet 27 is still moving in the counterclockwise direction and the head of the hook lever 23 is in contact with the support lever 25, it cannot be engaged with the hook portion. At this time, since the hook lever 23 cannot move, it is in a fixed state, and the spring 34 acts to bias the signal lever 21 downward, so that the tip of the signal lever 21 is guided by the upper surface of the spiral groove of the screw 20. To rise. The signal lever 21 ascends following the spiral groove of the screw 20, drops to the upper surface of the lower groove at the groove end, and swings at this portion. The eccentric cam 35 connected to the one-turn cam 11 rotates in the direction of the arrow in FIG. 2 to push the driven portion 36 provided on the movable piece support lever 25 against the spring 26 in the clockwise direction. When the movable piece support lever 25 rotates clockwise and passes over the head of the hook lever 23, the hook lever 23, which is biased upward by the spring 24, rises and locks the movable piece support lever 25 at the hook portion.

Even after the hoisting further progresses and the driven part is displaced to the maximum by the cam 35, the movable piece support lever 25 moves to the hook lever 23.
2 is maintained, and the holding of the movable piece support lever 25 is completed at the position where the magnet 27 keeps the movable piece 28 in contact. The stop lever 10 is engaged with the one-rotation cam 11 at the lower part of the cam 35 at the position where the winding and the shutter charge are completed, the driving of the motor 1 is stopped, and one operation of the camera by the motor 1 is completed.

As described in detail above, according to the trailing curtain activation control device of the present invention, the shutter mechanism of the motor drive camera can be made simple and reliable.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of a control device according to the present invention together with the overall configuration of a motor drive mechanism of a single-lens reflex camera, and FIG. 2 is an enlarged perspective view showing an embodiment of the control device according to the present invention. Is. DESCRIPTION OF SYMBOLS 1 ... Motor, 2 ... Unidirectional clutch gear 3 ... Ratchet gear, 4 ... Ratchet arm 5 ... Mirror drive lever, 6 ... Drawing lever 7 ... Drawing restoring spring, 8 ... Trigger lever 10 ... Stop lever, 11 ... One rotation cam 15 ... Mirror Applicator, 16 ... Foot 17 ... Gear, 18 ... Frixion gear 19 ... Gear, 20 ... Screw 21 ... Signal lever, 22 ... Bend 23 ... Hook lever, 24 ... Spring 25 ... Movable piece support lever, 26 ... Spring 27 ... Magnet, 28 ... Movable piece 29 ... Front curtain start lever, 30 ... Rear curtain start lever 31 ... Pin, 32 ... Rear curtain cam 33 ... Cam, 34 ... Spring 35 ... Cam, 36 ... Follower

Claims (1)

[Scope of utility model registration request] 1. A rear curtain start control device for a motor drive camera using a motor which has an electromagnetic shutter and is rotated in a first direction at the time of shutter release and is rotated in a second direction after the shutter operation is completed. A screw that has a spiral groove in it and that is connected to a first gear that rotates in the forward and reverse directions by receiving the rotational force from the motor; and a second screw that rotates from the first gear via a one-way clutch.
A one-rotation eccentric cam connected to a gear, a rear-curtain cam integrally provided on a rear-curtain gear to which the rotational force for the shutter curtain set is transmitted from the second gear, the screw, one-rotation eccentric cam, rear A first extending portion having a rotating shaft center in a triangular shape that is formed between the shaft centers of the blade gears, and extending from the rotating shaft center between the screw and the one-rotation eccentric cam, and having a movable piece at a tip thereof; A second extension extending from the axis of rotation between the one-rotation eccentric cam and the trailing blade and being applied with a biasing force in a direction of contacting the one-rotation eccentric cam
A support lever having an extending portion, and the support lever is coaxially fixed to the support lever, extends between the one-rotation eccentric cam and the trailing blade gear, and abuts a part of the support lever to apply the biasing force. A trailing-curtain start lever that locks the trailing-curtain cam, an electromagnet that attracts and holds the movable piece against the biasing force of a support lever that supports the movable piece, and a gap between the electromagnet and the one-rotation eccentric cam. A hook lever that is biased and pivoted so that the hook portion moves in a direction orthogonal to a rotation plane of the support lever and can lock the support lever; and a hook lever that is coaxially pivoted with the hook lever. A signal lever that follows the rotation of the screw and releases the locking of the support lever against the biasing force of the hook lever, and the screw rotates forward in synchronization with a release signal to cause the hook to rotate. The support by lever The lock of the lever is released, the screw is reversed in synchronization with the winding of the shutter, the hook lever brings the support lever to a height at which the support lever can be locked, and the one-rotation eccentric cam causes the support lever of the support lever to move. The second extending portion is driven to be locked to the hook lever, and the trailing blade start lever is used to lock the trailing blade cam to lock the trailing blade gear at a predetermined position. Rear drive activation control device for motor drive cameras.