JPH0245855Y2 - - Google Patents

Description

[Detailed description of the invention] (Field of application) The present invention is an electromagnetically controlled shutter, for example, a shutter locking member is attracted and held by the magnetic force of a magnet against the separation spring force applied to the member, and the magnetic force is applied by electrical operation. This invention relates to a shutter that controls exposure time using an electromagnet of the type that releases a shutter locking member by releasing the shutter locking member, and uses the separation spring force not only for releasing the shutter locking member but also as a driving force for the shutter blade.

(Prior art) Previously, Japanese Unexamined Patent Application Publication No. 1983-1981 proposed by the present applicant
As in No. 118628, in addition to the force of the shutter blade drive spring, the shutter blade is also accelerated by the repulsive force of the armature separation spring, improving the running speed of the shutter blade, especially the sharpness of the rise, and effectively Proposals aimed at increasing the speed of the curtain are known. However, in this case, two springs are used to drive one blade group, so the variations in spring force and spring shape due to a single spring component are doubled compared to when driving with one spring.
It becomes difficult to match the running characteristics of the leading blade group and the trailing blade group. Therefore, the so-called "α" of "predetermined exposure time + α", which is the time difference between the timing of energization to the leading blade and trailing blade control magnets to achieve the predetermined exposure time, may cause uneven exposure. If the gain value varies from shutter unit to shutter unit, other problems may occur.

(Summary of the invention) The present invention is a further improvement on the conventional proposal described above, and utilizes the force of a separation spring that urges the shutter locking member that releases the shutter locking member to separate from the electromagnet. In an electromagnetic control shutter that auxiliarily energizes a drive member to accelerate the movement of the shutter blade for exposure, by making the substantial start timing of the auxiliary energization of the separation spring variable, the shutter blade The drive speed can be easily adjusted.

(Example) Hereinafter, the present invention will be described in detail based on an example using an electromagnet of a type that attracts and holds a shutter locking member by the magnetic force of a permanent magnet.

FIG. 1 is a perspective view of a vane-type focal plane shutter to which the present invention is applied, and FIG. 2 shows the shutter in a charged state.

In the figure, 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 so as to maintain a constant gap, 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 the exposure window is opened and closed by the operation of a known link mechanism. 3a, 3b, 3c, and 3d are divided blades constituting the leading blade; in this figure, the divided blades constituting the trailing blade are hidden by the shutter base plate 1 and are therefore not shown. Further, each of the divided blades of the leading blade and the trailing blade is made of a titanium material, a plastic material, or the like in order to reduce the movable mass, reduce the driving torque, and reduce the loosening of the locking pawl, which will be described later.

Reference numeral 4 designates a leading blade drive lever, which is rotated clockwise by a leading blade driving spring 6, and includes a first arm having a locking portion 4a protruding from its upper surface, and an armature separation spring described later. It has a second arm in which a pin 4b that receives a drag force is implanted on the upper surface, and a third arm in which an interlocking pin 4c that engages with a leading blade drive arm (not shown) is implanted in the lower surface. A charge pin 4d is implanted on the lower surface of the arm of the first arm.

Reference numeral 10 denotes a leading blade locking lever, which is rotatably supported by a shaft 26, and has a locking piece 8 pivotally attached to its tip by a shaft 12. The locking portion 4a of the drive lever 4 is prevented from rotating by a stopper (not shown).
It is regulated to the extent that it can be captured.

Next, reference numeral 5 denotes a rear blade drive lever, and each of the four arms has a locking member 5a at the tip, a member 5b that receives the resistance of the armature separation spring 31, and a rear blade drive arm (not shown) for operating the rear blade drive arm. The trailing blade drive pin 5c and the stopper pin 5d of the trailing blade driving lever 5 are implanted and biased to rotate clockwise by the trailing blade driving spring 7, and are constructed in the same manner as the leading blade driving lever 4. ing. Reference numeral 9 denotes a rear blade locking piece provided on the rear blade locking lever 11. The stopper (9) is designed to be rotatable about the shaft 13 as much as possible to grip the locking member 5a of the rear blade drive lever 5. (not shown), and the spring 1
5 in the clockwise direction.

Reference numeral 11 denotes a trailing blade locking lever, which is rotatable around a shaft 27 like the leading blade locking lever 10, and has a locking piece 9 at its tip that is to be engaged with the locking member 5a of the trailing blade drive lever 5. is pivotally supported by a shaft 13, and a spring 1
5, it is rotated clockwise.

Next, 16 is a leading blade control electromagnet, and 17 is a trailing blade control electromagnet, both of which use permanent magnet type electromagnets. 18 and 19 are yokes, which are permanent magnets. Coils 20 and 21 are designed to cancel the magnetic force of the permanent magnet by energizing them. Armatures 22 and 23 are attached to one end of the shutter blade locking levers 10 and 11, respectively, so as to be able to rotate slightly about shafts 24 and 25.

As mentioned above, the shutter blade locking levers 10 and 11 are rotatable around the shafts 26 and 27, and when the coils 20 and 21 are not energized, the armatures 22 and 23 are attracted by the yokes 18 and 19. It is located in the position shown in Figure 2. Reference numerals 28 and 29 are armature adsorption springs that urge the levers 10 and 11 to rotate clockwise.

Reference numerals 30 and 31 are armature separation springs stronger than the adsorption springs, which are wound around shafts 26 and 27, respectively, one end of which abuts against the locking levers 10 and 11;
The other end contacts the pins 4b, 5b on the blade drive levers 4, 5 at the end of the shutter charge, and is stored as the levers 4, 5 rotate.

Reference numerals 34 and 35 are stoppers according to the present invention that restrict the rotation of the locking levers 10 and 11, and are composed of eccentric dowels that can be adjusted with a screwdriver or the like.
The rotation restriction positions of 0 and 11 can be changed.

32 and 33 are stoppers that restrict the opening of the arm on the free end side of the armature separation springs 30 and 31, and are comprised of eccentric dowels that can be adjusted with a screwdriver, etc. It is becoming possible to change.

36 is a charge lever rotatably attached to the shutter base plate 1 by a support shaft 38;
After being rotated clockwise to perform charging, it is urged by a spring 37 to return to rotation in the counterclockwise direction. Each tip of the charge lever 36 is adapted to engage with a charge pin 4d of the leading blade drive lever 4 and a charge pin 5d of the trailing blade drive lever 5. 40 is charge lever 3
This is a stopper that restricts the rotation of 6.

Next, the operation of the embodiment configured as described above will be explained. Figure 2 shows the state in which the shutter is charged, Figure 3 shows the state in which the shutter blade is running, and Figure 4 shows the state in which the shutter blade is running.
The figure shows the shutter blades running at full power.

When the shutter is charged, the locking levers 10 and 11 are connected to the armatures and the electromagnets 16 and 17.
The leading blade drive lever 4 and the trailing blade drive lever 5 are in the position shown in FIG. It's stopped.

When the coil 20 of the leading blade control electromagnet 16 is energized by a control circuit (not shown) in conjunction with the release operation, the armature 22 that has been attracted to the yoke 18 is moved because the magnetic force of the permanent magnet of the yoke 18 disappears. , the armature is separated from the yoke 18 by the force of the armature separation spring 30, and the leading blade locking lever 10 is rotated counterclockwise. This tip blade locking lever 1
0 rotates by a certain angle, the leading blade locking piece 8 at the tip disengages from the locking portion 4a of the leading blade drive lever 4, and the leading blade drive lever 4 starts rotating clockwise. . At this time, the leading blade drive lever 4 begins to be pushed clockwise by the force of the armature separation spring 30 on the pin 4b in addition to the force of the leading blade driving spring 6, but the leading blade locking lever 10 is pressed against the stopper 34. Until they come into contact, the force of the armature separation spring 30 is also used to rotate the leading blade locking lever 10 counterclockwise, so the entire spring force at that time is not applied to the leading blade driving lever 4. do not have. Therefore, the stopper 3 serving as an eccentric dowel
4 to shorten the distance from the disengagement between the leading blade locking piece 8 and the locking portion 4a until the leading blade locking lever 10 abuts the stopper 34, the more the separation spring is adjusted. Since the leading blade drive lever 4 is pushed while the amount of deflection of the drive lever 30 is large, the force pushing the drive lever 4 clockwise increases and the timing of the push becomes earlier, causing rotation of the drive lever 4. The rise becomes sharper. This rotation is transmitted to the leading blade drive arm (not shown) via the leading blade drive pin 4c, and the divided blades 3a, 3b, 3c, and 3d of the leading blade travel to expose the exposure window 1a.
is opened and exposure begins. The separation spring 30 gradually opens while pushing the pin 4b with its arm on the free end side, but when that arm comes into contact with the stopper 32 on the leading blade locking lever 10 and is restricted, the pin 4b is no longer connected to the release spring 30. When separated, the drive lever 4 also engages the locking lever 10.
is no longer affected by the action of the spring 30.

Therefore, by adjusting the stopper 32, which is an eccentric dowel, and adjusting the final operating angle of the separation spring 30, the stroke of the force exerted by the separation spring 30 to push the leading blade drive lever 4 can be changed.

Thereafter, the leading blade locking lever 10 is rotated clockwise by the armature attraction spring 28, and the armature 22 is attracted to the yoke 18, which is a permanent magnet, of the electromagnet 16, which has already been de-energized.

When the coil 21 of the trailing blade control electromagnet 17 is energized a predetermined time after the leading blade control electromagnet 16 is energized, the armature 23 that was attracted to the yoke 19 is separated from the yoke 19 by the drag force of the armature separation spring 31. Leave. As a result, the armature drive lever 11 rotates counterclockwise as in the case of the leading blade described above, and the trailing blade member locking piece 9
The engagement between the rear blade drive lever 5 and the locking member 5a is released, the rear blade drive lever 5 rotates clockwise, and the rear blade divided blades 39a, 39b, 39c,
39d starts running, closes the exposure window 1a, and ends the exposure.

While the trailing blade is running, as in the case of the leading blade described above,
The armature separation spring 31 pushes the rear blade drive lever 5 and the armature adsorption spring 29
The armature 23 is returned to the yoke 19 by suction. Also, stoppers 33 and 35, which are eccentric dowels, are provided on the rear blade system.
It also plays the same role as the tip blade type.

After this exposure is completed, when the charge lever 36 rotates clockwise around the shaft 38 in conjunction with the winding of the camera from the state shown in FIG. 4d and 5d to rotate the levers 4 and 5 counterclockwise, charging the drive springs 6 and 7 and returning the leading and trailing blades to their pre-exposure state.

The pins 4b and 5b on the drive levers 4 and 5 release the armature separation springs 30 and 5b at the end of this charging operation.
31 and pushes counterclockwise around 26 and 27. At this time, the armature is attracted by the permanent magnet, so the locking levers 10 and 11 do not rotate and the springs 30 and 3
1 is bent and stored energy. When the locking parts 4a, 5a of the drive levers 4, 5 hit the locking pieces 8, 9, the locking pieces rotate counterclockwise around the shafts 12, 13 and escape, and the locking parts 4a, After 5a passes, the spring 14,
The rotation returns with a force of 15, and the hook portion locks the locking portion 4a,
5a is locked, and the hoisting operation is completed.

In the above embodiments, an electromagnet of the type that attracts and holds the shutter locking member using the magnetic force of a permanent magnet and releases the shutter locking member by dissipating the magnetic force by applying electricity has been described. It can also be applied to a type of electromagnet that uses the magnetic force of an energized permanent magnet to attract and hold the shutter locking member, and when the energization is stopped, the magnetic force disappears and the shutter locking member is released. A similar effect can be obtained.

In addition, in the embodiment, stoppers 32, 33, 34,
Although the position adjusting means of 35 has been described as being an eccentric dowel, it goes without saying that it may be replaced by other known mechanical means such as a sliding type.

In addition, in this embodiment, the locking levers 10, 11 are moved by the stoppers 34, 35 whose positions can be changed.
The rotational position of the armature separation springs 30 and 31 can be used to adjust the pushing timing of the blade drive levers 4 and 5.
The magnitude and acceleration timing of the force accelerating the shutter blades by 0 and 31, that is, the magnitude and acceleration timing of the force accelerating the blade drive levers 4 and 5, can be adjusted, and the stoppers 32 and 33 are movable in position. Armature separation spring 3
The opening angle of the arm on the free end side of 0 and 31 is made variable, so that the stroke of the force that accelerates the shutter blades by the separation springs 30 and 31, that is, the stroke of the force that accelerates the blade drive levers 4 and 5, is made adjustable. There is. However, the former stopper 34,
The purpose of the present invention can be sufficiently achieved by making only the blade drive levers 35 movable and adjusting the magnitude of the accelerating force and acceleration timing of the blade drive levers 4 and 5, and the configuration of the embodiment can be finely adjusted. This shows the implementation to make it more detailed.

Further, in this embodiment, the stoppers 34 and 35 are configured so that both of them can be displaced, but it goes without saying that the effects of the present invention can also be achieved by making only one of them movable. Without,
It is possible to implement.

(Effects of the invention) As explained above, the present invention makes it possible to vary the substantial start timing of the auxiliary biasing of the separation spring that auxiliarily biases the shutter blade drive member (in the embodiment, the magnitude of the accelerating force is As a result, the range in which the running characteristics of the shutter blades could be changed expanded, and at the same time fine adjustment became effective. Therefore, it is possible to eliminate uneven exposure and deviations in deviation values through adjustment.
Furthermore, it is possible to obtain the effect that there is no need to make the precision of the parts of the spring itself strict.

[Brief explanation of the drawing]

Fig. 1 is a perspective view showing an embodiment of the present invention, Fig. 2 is a plan view showing the shutter of the embodiment of the invention in a charged state, and Fig. 3 is a plan view showing the state in which the shutter blades are running. FIG. 4 is a plan view showing a state in which the shutter blades have completed traveling. 1: Shutter base plate, 4: Leading blade drive lever,
5: Rear blade drive lever, 6: Lead blade drive spring,
7: Trailing blade drive spring, 8: Leading blade locking piece, 9: Trailing blade locking piece, 10: Leading blade locking lever, 11: Trailing blade locking lever, 16: Leading blade control electromagnet, 1
7: Rear blade control electromagnet, 28: Lead blade armature adsorption spring, 29: Rear blade armature adsorption spring, 30: Lead blade armature separation spring,
31: Rear blade armature separation spring, 36: Charge lever, 32: Leading blade armature separation spring stopper, 33: Rear blade armature separation spring stopper, 34: Leading blade locking lever stopper, 3
5: Rear blade locking lever stopper.

Claims (1)

[Claims for Utility Model Registration] (1) An electromagnet, a shutter locking member supported movably between an adsorption position and a separation position to the electromagnet, and releasing the shutter lock at a predetermined separation position; a release spring for biasing the locking member to the release position; a shutter blade drive member for moving the shutter blade for exposure after the shutter lock is released; and a shutter blade drive member for driving the shutter blade for exposure. , after the shutter locking member has released the shutter lock, the shutter locking member is locked, and the subsequent biasing force of the separation spring is supplementarily applied to the shutter blade drive member for a predetermined period of time. An electromagnetically controlled shutter comprising: a drive mechanism; further comprising a displacement mechanism for displacing a locking position of a drive shutter locking member by the drive mechanism. (2) Utility Model Registration Claim 1, wherein the displacement mechanism is an electromagnetic control shutter that changes the contact position of a stopper that determines the locking position of the shutter locking member.