JPS6217737B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an electromagnetic release shutter, and more particularly to an improvement in a locking mechanism that locks the shutter in the charged state when the shutter is charged to its initial position.

In general, the locking mechanism of an electromagnetic release shutter consists of a locking member that stores a drive spring for driving the shutter blades by the charge operation of the shutter, and locks the spring, and a locking member that locks the drive spring by the actuation force of an electromagnet. and a mechanism that is activated by the lock to release the lock.

The locking mechanism of the conventional electromagnetic release shutter is
When the armature was activated, the shutter was unlatched and the shutter blades were allowed to travel. Specifically, the shutter drive lever to which the drive spring is applied is locked by a tension lever, the armature is actuated by energization control of an electromagnet, and the force is used to release the tension lever and move the shutter. The structure is such that the drive lever is free and the shutter travels by the biasing force of the drive spring.

However, with this conventional configuration, when an impact is applied to the camera, the tension lever comes off due to vibration, causing the shutter to move incorrectly.

Utility Model Application No. 54-33137 as an improved proposal of the conventional one
number is known. In order to solve the above-mentioned conventional problems, this improved proposal provides a set member that holds both the front and rear curtain armatures in a charged state until the release button is operated (for the movable mirror). The setting member is held to prevent both armatures from moving in the activation direction even when an impact is applied to the camera.

However, in the above-mentioned improved proposal, even if there is an impact, both armatures are held down and do not move, but in reality, the front curtain and Both shutter drive levers for the rear curtain are not held down reliably, and it is conceivable that one of the two shutter drive levers may become unlatched due to an impact, causing the shutter to move incorrectly.

The present invention has been made in order to solve the above-mentioned conventional problems, and can reliably prevent the shutter from erroneously moving when an impact is applied to the camera, and can also prevent erroneous shutter movement even if there is a slight dimensional error in each part. However, our objective is to provide an electromagnetic release shutter that can always provide accurate exposure.

In order to achieve the above object, the present invention provides a front curtain lever member and a rear shutter curtain lever member to which a coil spring or the like is applied for driving the shutter front curtain blade and the shutter rear curtain blade in the shutter front curtain configuration and the shutter rear curtain configuration. The curtain lever member itself is directly locked by two locking members, and when the first locking member locks the lever member, the second locking member locks the lever member. and the second locking member is set to lock when the first locking member is released and the lever member is slightly rotated by force, Furthermore, the present invention is characterized by an electromagnetic release shutter in which each of the second locking members is controlled to a lock release position by an electromagnetic structure.

Hereinafter, the present invention will be explained in detail based on examples.

FIG. 1 is a perspective view of essential parts of an electromagnetic release shutter according to the present invention.

In FIG. 1, 1 is a shutter base plate, and an exposure window 1a is provided approximately in the center of the plane. A cover base plate 2 is attached to the shutter base plate 1 at a constant distance, and has an exposure window (not shown) at a position corresponding to the exposure window 1a. A leading blade and a trailing blade are provided between the shutter base plate 1 and the cover base plate 2, and are configured to open and close the exposure window 1a by operating a known link mechanism. 3a, 3b, 3c, 3
d is a divided blade constituting the leading blade; in this figure, the divided blade constituting the trailing blade is hidden by the shutter base plate and is therefore not shown.
Further, each of the divided blades of the leading blade and the trailing blade is made of titanium, plastic, or the like in order to reduce the movable mass.

4 is a leading blade drive lever, and a leading blade driving spring 6 whose urging force is adjusted by a ratchet gear 29
It is urged to rotate clockwise by the leading blade drive lever 4, and a leading blade drive arm (not shown) having a locked portion 4a at the upper end thereof and a leading blade drive arm (not shown) at the lower end of the leading blade drive lever 4 is linked to the rotation of the leading blade drive lever 4. A leading blade drive pin 4b is implanted for this purpose. Incidentally, the leading blade drive lever 4 is also made of plastic material or the like in the same way as the divided blades 3a, 3b, 3c, and 3d, so as to reduce the movable mass. 8 is a leading blade locking member;
It is fixed to the shutter base plate 1 and rotatably fitted to a support shaft 10 that supports the control unit base plate 12. The tip of the protruding portion 8b of this leading blade locking member 8 is connected to the locked portion 4a of the leading blade driving lever 4 described above.
After the shutter is charged, when the other locking means is released, the spring 6 engages with the other locking means to restrict the subsequent movement of the leading blade. 8a is a release signal pin, which is fixed to the protrusion 8b. This leading blade locking member 8 is biased counterclockwise by a spring.
In the charge state shown in the figure, the release signal pin 8a
The position is regulated by contacting the notch end face of the control unit base plate 12.

Next, 5 is a rear blade drive lever, and a rear blade drive pin 5b for operating a locked portion 5a and a rear blade drive arm (not shown) is installed, and the urging force is adjusted by a ratchet gear 30. It is biased to rotate clockwise by a trailing blade drive spring 7, and is configured similarly to the leading blade driving lever 4. A support shaft 11 is fixed to the shutter base plate 1 and supports the control unit base plate 12, and the rear blade locking member 9 is rotatably fitted therein. A release signal pin 9 is attached to the rear blade locking member 9.
a and a protruding portion 9b that engages with the locked portion 5a of the trailing blade drive lever 5. The rear blade locking member 9 is also biased counterclockwise by a spring, and its position is regulated by the pin 9a coming into contact with the end face of the cutout of the base plate 12. In addition, 27
28 is a brake member for the leading blade that brakes the leading blade driving pin 4b of the leading blade driving lever 4 to reliably stop the movement of the leading blade driving lever 4, and 28 similarly stops the movement of the trailing blade driving lever 5. This is a brake member for the rear blade.

Next, 13 is an electromagnet for controlling the leading blade, and 14 is an electromagnet for controlling the trailing blade, both of which are suction type electromagnets. The leading blade control electromagnet 13 and the trailing blade control electromagnet 14 are arranged line-symmetrically as shown, so as to cancel out the difference in attitude caused by the influence of gravity. 15 and 18 are yokes, around which coils 16 and 19 are wound. 17
and 20 are armature levers whose armature parts are integrally molded, and are rotatably attached to support pins 17b and 20b provided at one end of yokes 15 and 18, and actuating parts 17a and 2
0a is formed at the end opposite to the end on the suction surface (armature part) side. This armature lever 17
is biased to rotate clockwise by a spring (not shown), and the rotation is caused by the contact between the operating portion 17a of the armature lever 17 and the pin 21 implanted in the control unit base plate 12. When the coil 16 is energized and the armature lever 17 is attracted to the yoke 15, the actuating portion 17a comes into contact with the release signal pin 8a of the leading blade locking member 8, and the corresponding The locking member 8 is pressed clockwise. Further, the armature lever 20 is also configured in the same manner as the armature lever 17, and when the coil 19 is energized, the armature lever 20 rotates against a spring (not shown), so that the actuating portion 2a is rotated. comes into contact with the release signal pin 9a of the rear blade locking member 9 and presses the locking member 9 clockwise.

Further, as shown in FIG. 2, a charge lever 23 is rotatably attached to the shutter base plate 1 by a support shaft 24, and is urged to rotate counterclockwise by a charge lever return spring 25. . When charging the shutter, this charge lever 23 is rotated clockwise by a charge member 26 provided on the camera side, and a mirror up signal is output in response to the camera release signal, and the charge member 26 is moved to the position 26a. When it is moved, it is rotated counterclockwise by a spring 25. Further, the charge lever 23 is engaged with the charge pin 4c, and the leading blade drive lever 4 is engaged with the charge pin 4c.
The first protrusion 23a and the charge pin 5c engage with each other to return the rear blade drive lever 5 to the charged state and securely lock it in that position. A second protrusion 23b is provided.

Next, the operation of the embodiment configured as described above will be explained with reference to FIG.

In the shutter charge state, the flat portions at the tips of the first and second projections 23a and 23b of the charge lever 23 engage with the charge pins 4c and 5c of the leading blade drive lever 4 and the trailing blade drive lever 5, respectively. This locks the leading and trailing blades from running. In this state, when a mirror up signal is output from the camera release signal, the charge member 26 moves to the position 26a, so the charge lever 23 is rotated counterclockwise by the charge lever return spring 25 to lock the is canceled. Therefore, the leading blade driving lever 4 and the trailing blade driving lever 5 are slightly rotated clockwise by the spring 25, and the leading blade driving lever 4 is rotated at its locked portion 4a.
and the protruding portion 8b of the leading blade locking member 8 are in contact with each other, and the trailing blade drive lever 5 is in a position where its locked portion 5a and the protruding portion 9b of the trailing blade locking member 9 are in contact with each other. Each is locked with a small release torque.

Thereafter, when the leading blade running signal is output and the coil 16 of the leading blade control electromagnet 13 is energized by a control circuit (not shown), the armature lever 17 is attracted to the yoke 15 and moved counterclockwise. Rotate to. Along with this rotation, the actuating portion 17a also rotates counterclockwise, and momentarily contacts the release signal pin 8a of the leading blade locking member 8 from the non-engaged state of the shirge state, and the armature lever 17 Press the release signal pin 8a clockwise while applying a hammer effect. Therefore, the leading blade locking member 8 rotates clockwise about the support shaft 10, and the engagement between the protruding portion 8b and the locked portion 4a of the leading blade driving lever 4 is released. At this time, the leading blade drive lever 4 starts rotating clockwise, and this rotation is transmitted to the leading blade driving arm (not shown) via the leading blade driving pin 4b, and the divided blades of the leading blade are rotated. 3a, 3
b, 3c, and 3d run to open the exposure window 1a,
Exposure begins.

After a predetermined shutter time has elapsed since the leading blade control magnet 13 is energized, the coil 1 of the trailing blade control electromagnet 14 is turned on.
9 is energized, and the armature lever 20 is attracted to the yoke 18. As a result, the actuating portion 20a of the armature lever 20 presses the release signal pin 9a of the rear blade locking member 9, and the rear blade locking member 9 is rotated clockwise, as in the case of the leading blade described above. let At this time, the engagement between the protruding part 9b of the rear blade locking member 9 and the locked part 5a of the rear blade drive lever 5 is released, so that the divided blades (not shown) of the rear blade start running. Then, the exposure window 1a is closed and the exposure is completed.

After this exposure is completed, when the charge lever 23 is rotated clockwise by the charge member 26 in conjunction with the winding of the camera, the charge pin 4c of the leading blade drive lever 4 first comes into contact with the side surface of the first protrusion 23a. At the same time, the charge pin 5c of the trailing blade drive lever 5 comes into contact with the side surface of the second protrusion 23b and is slid and pressed, so that the leading blade drive lever 4 and the trailing blade drive lever 5 are driven to charge. , both pins 4c and 5c are connected to both protrusions 23a and 2
At the position where it comes into sliding contact with the flat part of the tip of 3b, the shutter is returned to the charged state shown in FIG. 2, and
At the same time, the shutter leading blade and trailing blade are also charged, and are locked again at that position to complete the shutter charging operation.

At this time, the leading blade locking member 8 and the trailing blade locking member 9 have each returned to the locking position shown in the second figure by the spring, but at the end of the shutter charge stroke, the leading blade drive lever 4 and The locked parts 4a and 5a of the rear blade drive lever 5 pass through the protrusions 8b and 9b of the locking members 8 and 9, respectively, and charging is completed in the state shown in FIG. 2.

Characteristic features of the above-mentioned embodiments are shown below.

(1) Two locking members, namely charge lever 2
3, the leading blade locking member 8, and the trailing blade locking member 9, the leading blade drive lever 4 and the trailing blade drive lever 5, which are given a biasing force for driving the shutter, are locked in two stages. It is possible to reliably prevent the shutter blade from becoming unlatched due to impact or the like and causing the shutter to run erroneously.

(2) Leading blade drive lever 4 and trailing blade drive lever 5
In the two-stage locking, the locking phases of the charge lever 23 as the first locking member and the leading blade locking member 8 and trailing blade locking member 9 as the second locking member are shifted, so if Even if there are slight dimensional errors in each member, reliable two-step locking is possible. Further, a second locking member that can lock the drive levers 4 and 5 after the first locking member is released from locking is provided.
An electromagnet 1 controls the energization of the locking members 8 and 9 in accordance with the shutter speed.
3 and 14. Therefore, even if the first locking member (charge lever 23) is activated due to an extremely strong impact and the first lock is released, the second locking member will immediately lock the second locking member. The shutter can be opened and closed in response to the energization control of the electromagnets 13 and 14. Also, due to an even stronger impact, the second
Even if the second locking member moves, the second locking member is originally the blade drive lever 4, 5.
4. In the fully charged state, they are not engaged and no adverse effects occur, and the locking members 8 and 9, which serve as the second locking members, can be automatically returned to the fully charged position by a spring.

(3) Charge lever 23 as the first locking member
When the two blade drive levers 4 and 5 are engaged with each other in the charged state shown in FIG. 2, the two drive springs 6 and 7
However, as is clear from FIG. 2, both charge pins 4c and 5c are
a, 23b, and the flat portions are perpendicular to a radial line passing through the center of rotation of the charge lever 23. Therefore, the biasing force of the drive springs 6 and 7 is applied toward the center of the charge lever 23, and is not applied strongly in the direction of unlocking the charge lever 23.

(4) The charge lever 23 as the first locking member is configured to have two functions of charging and locking the blade drive levers 4, 5 and the blades in one member, which is effective in terms of number of parts and miniaturization. is large.

(5) Since the first locking members in both shutter configurations are shared by one member, the charge lever 23, the timing of releasing the lock of the first locking members is the same, and no matter what the high-speed shutter speed is. I can handle it.

As explained above, the present invention can reliably prevent the shutter from erroneously moving even if a shock is applied to the camera, and even if there is a slight dimensional error in the parts of the shutter locking mechanism, the timing for controlling the energization of the electromagnet can always be adjusted. It is possible to provide an electromagnetic release shutter that can perform accurate exposure corresponding to

[Brief explanation of the drawing]

FIG. 1 is a perspective view of essential parts of an electromagnetic release shutter according to the present invention, and FIG. 2 is a plan view thereof. DESCRIPTION OF SYMBOLS 1... Shutter base plate, 4... Leading blade drive lever, 5... Trailing blade driving lever, 8... Leading blade locking member, 9... Trailing blade locking member, 13... Leading blade control electromagnet, 14 ... Electromagnet for rear blade control, 23
...Charge Labor.

Claims (1)

[Scope of Claims] 1. A shutter leading blade, and a leading lever member that causes the shutter leading blade to travel by a driving force accompanying rotation in a first direction from a shutter travel preparation position. a front curtain biasing member that biases the front curtain lever member in the first direction; a shutter rear curtain blade; and rotation in the first direction from the shutter travel preparation position. a rear curtain lever member that causes the rear curtain blade of the shutter to travel by driving force accompanying the shutter; and a rear curtain structure that biases the rear curtain blade in the first direction. The biasing member is supported so as to be movable between a locking position for locking the front curtain lever member and a lock release position in order to lock the shutter front curtain configuration in the shutter travel preparation position. a first front curtain locking member; and a first front curtain locking member for locking the front curtain lever member in a state where the front curtain lever member is rotated in the first direction by a slight angle from the shutter travel preparation position. , a second front curtain locking member supported so as to be movable between a locking position and a locking release position; and a second front curtain locking member supported to be movable between a locking position and a locking release position; a first trailing curtain locking member supported so as to be movable between a locking position for locking the curtain lever member and a locking release position; a second trailing curtain locking member supported so as to be movable between a locking position and a locking release position in order to lock the trailing curtain lever member in a state of rotation in the first direction; , a leading curtain electromagnet configuration that drives the leading armature from the first position to the second position by controlling the energization of the coil, and a trailing curtain armature that drives the trailing curtain armature from the first position to the second position by controlling the energization of the coil. a trailing curtain electromagnet configuration; and a leading curtain that moves the second leading curtain locking member from the locking position to the unlocking position in conjunction with the driving of the leading blade armature to the second position. an interlocking member; and a trailing curtain interlocking member that moves the second trailing curtain locking member from the locking position to the locking release position in conjunction with the driving of the trailing curtain armature to the second position. An electromagnetic release shutter characterized by the following.