JPH0710340Y2 - Shutter blade actuation device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of use] The present invention relates to a blade driving device for a motor-driven shutter used in a compact camera or the like.

[Conventional technology]

2. Description of the Related Art Recently, a camera with a lens shutter that can change the focal length of a lens (which is often used in, for example, a compact camera) has a motor-driven shutter blade actuating device that opens and closes a shutter blade by using a motor as a power source. ing. As such a shutter blade operating device,
For example, there are those shown in FIGS. 4 and 5. In this operating device, the motor board 101 in FIG.
A fixed shaft 105a is fixed to the fixed shaft 105a, and an opening / closing lever 106 is rotatably attached to the fixed shaft 105a. The pin portion 106a of the opening / closing lever 106 projects from the motor substrate 101 and engages with the shutter blades 105 and 104, and the shutter blades 105 and 104 rotatably engage with the fixed shaft 105a.

Here, when a well-known control circuit (not shown) is operated, a drive signal of a two-phase excitation method of bipolar drive is output to the two coils, the stator is excited and the rotor turns to the left, and as shown in FIG. The shutter blade 105 meshing with the tooth portion by the gear 102 turns right around the fixed shaft 105a, and at this time, the groove 105c actuates the pin portion 106a of the opening / closing lever 106, and the opening / closing lever 106 also turns right. Therefore, the shutter blade 104 is operated by the pin 106a in the groove 104c,
Turn left about axis 104a.

As the rotor continues to turn left, the shutter blade 10
The shutter opening is gradually opened by the image edges 104b and 105b of 4,105, and the exposure is controlled by a combination of the aperture and the exposure time, and when the desired value is reached, the rotor is reversed to two coils by a known control circuit. Since the drive signal for
The rotor instantaneously reverses and the shutter blade 105 is rotated by the gear 102.
Is rotated to the left around the fixed shaft 105a, and the shutter aperture OA is closed together with the shutter blade 104.

By the way, conventionally, negative color films (photosensitive materials) have been widely used for compact cameras and the like, and this film has a wide latitude, and even if there is some variation or unevenness in exposure control, it can be corrected during printing. So there are few problems. However, in a camera that uses a fixed image sensor such as a reversal film or a CCD that has been recently developed, since the sensitivity of the photosensitive material used for this camera is narrow, there are large variations and unevenness in shutter exposure control. Affects and a good image cannot be obtained.

[Problems to be solved by the device]

However, in such a conventional shutter blade actuating device, as shown in FIG. 4, since the sleeve portion 106b of the opening / closing lever 106 has to be fitted to the fixed shaft 105a by a clearance fit, there is no looseness between them. Since the fixed shaft 105a and the shutter blade 105 must also be fitted with a clearance, there is a looseness in the fitting.
Further, although the opening / closing lever 106 is a component that rotates at the same time as the shutter blades 105, in reality, a clearance fit is also required at the portion where the pin portion 106a engages with the shutter blades 105, and the sleeve portion 106b and the shutter There was a lot of looseness between the blade 105 and the blade.

If one of the sleeve portion 106b of the opening / closing lever 106, the shutter blade 105, and the fixed shaft 105a is made of synthetic resin or the like, it is necessary to increase the clearance in advance in consideration of the dimensional change of the material due to changes over time and changes in operating environment temperature. There is. For this purpose, the sleeve portion and the shutter blade 105 and the fixed shaft 105
The fit backlash with a tended to be even larger. Therefore, the opening / closing lever 106 moves the shutter blades 104, 105.
In some cases, it was not possible to perform stable operation, and the opening / closing operation of the shutter opening OA was varied and uneven, and it could not be performed accurately. As a result, it is not possible to perform exposure control with high precision, and it is impossible to use this shutter blade actuation device for a camera that uses a fixed image sensor such as a CCD and uses a photosensitive material with a narrow lattice. There were challenges.

By the way, in order to assemble the shutter blade operating device, the fixed shaft 105a is fixed to the motor substrate 101, and then the sleeve portion 106b is fitted into the opening / closing lever 106 on the fixed shaft 105a. Next, the motor board 101 is turned over once, the fixed shaft 105a and the pin portion 106a of the opening / closing lever 106 are fitted with the shutter blades 105, then the shutter blade 104 is fitted into the pin portion 106a, and then turned over again. Had returned to. Thus, the motor substrate 101 had to be turned over during the assembly process. Therefore, there is a problem in that assembling work by the robot is complicated and time is required for assembling due to the insertion of the flipping step.

[Means for Solving the Problems]

In order to solve such a problem, in the present invention,
A plurality of shutter blades that rotate around a fixed shaft to open and close the shutter opening; and an opening and closing lever that has a sleeve portion and an operating portion that are fitted into the shaft protruding from the shutter substrate and that operates the shutter blades. One of the shutter blades is supported by the outer circumference of the sleeve portion and the operating portion.

[Action]

Since one of the shutter blades is supported by the outer circumference of the sleeve portion and the operating portion, the play is reduced and the opening / closing lever is reliably and integrally rotated simultaneously with the shutter blades. Therefore, the opening / closing operation of the shutter opening by the shutter blade is accurately performed. Therefore, highly accurate exposure control can be performed by the shutter blades.

Further, during the assembling work of this structure, the shutter blade is fitted on the outer periphery of the sleeve portion of the opening / closing lever and the operating portion so that the shutter blade is attached to the opening / closing lever. Therefore, it is not necessary to turn over the motor board during the assembly process as in the conventional case. Therefore, since the step of turning over the motor substrate can be omitted, the assembly work and equipment by the robot can be simplified and the assembly time can be shortened.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings. First
1 to 3 are views showing an embodiment of a shutter blade operating device according to the present invention.

First, the configuration will be described.

In FIG. 1, the step motor M is rotatably mounted on the shaft 1.
A rotor R formed of permanent magnets that are supported by the magnets and are magnetized in the radial direction with multiple poles, two stators Sa and Sb that form poles that face the magnetic poles of the rotor R, and coils that are fitted and inserted into the stators. La, Lb, and each coil is connected to a known control circuit (not shown). The stators Sa and Sb are mounted on the upper plate as the first support member by the mounting shafts 2 and 3.
The magnetic pole part fixed to 11 and facing the rotor R has a pin S
The positions are regulated by a ₁ and Sb ₂ , respectively. Lower plate 4
A shutter opening OA is formed in the center of the (shutter substrate), the support shaft 1 of the rotor R extends through the lower plate 4 from the front side to the back side in FIG. It is fixed by press fitting.

As shown in FIG. 2, a shutter base plate 6 is attached to the back side of the lower plate 4, and a pair of shutter blades 7 and 8 is provided between the two.
Is located and its operating area is defined.
The shutter blade 8 is rotatably supported by the fixed shaft portion 9,
The shutter blade 7 is rotatably supported by the fixed shaft 10 and has an image edge portion 8a that forms an aperture opening and an image edge portion 7a that forms an aperture opening together with the image edge portion 8a. It has a groove 7b and a tooth portion 7c that meshes with the gear 5, and the fixed shaft portions 9 and 10 are arranged at positions facing the gear 5 with the shutter opening OA in between.

The shutter blade 7 has an opening / closing lever 11 as shown in FIG.
Is attached. The opening / closing lever 11 is provided on the lower plate 4 with a third
A substantially cylindrical sleeve portion 12 rotatably fitted to a fixed shaft portion 10 formed to project downward in the figure, and the sleeve portion 12
A flat plate portion 13 integrally formed with the first flat plate portion 13, and first and second pin portions 14 and 2 formed on both ends of the flat plate portion 13 so as to project in the vertical direction.
It consists of 15 (actuator). Flat part of the open / close lever 11
The second pin portion 15 protruding downward from the shutter blade 13 has shutter blades 7,
The first pin portion 14 that fits into the operation grooves 7b and 8b of the lower plate 8 and engages with the shutter blades 7 and 8 and projects upward is an insertion hole of the lower plate 4.
It is loosely inserted in 16, and the first pin portion 14 can come into contact with one end of the movable contact piece 17.

The movable contact piece 17 has a twisted coil shape and is supported by engaging with a boss portion 19 formed on the upper plate 18, one end of which is in contact with a fixed contact 20 provided on the upper plate and the other end of which is the upper plate. 18 stopper parts
While abutting on 21 and penetrating upper plate 18, it is joined to the pattern of printed wiring board 22 by soldering.

The inner circumference of the sleeve portion 12 of the opening / closing lever 11 is rotatably fitted into the fixed shaft portion 10, and the outer circumference 12a is fitted into a fitting hole 7d formed in the shutter blade 7 by a tight fit or a tight fit. . For this reason, in the opening / closing lever 11, the second pin portion 15 is fitted into and engaged with the operation groove 7b of the shutter blade 7, and the outer periphery 12a of the sleeve portion 12 has the shutter blade 7.
It means that it is fitted and engaged in the fitting hole 7d. That is, the shutter blade 7 is supported by the outer periphery 12a of the sleeve portion 12 and the second pin portion 15. Therefore, the opening / closing lever 11 is firmly connected to the shutter blade 7 with less play, and the shutter blade 7 is fixed to the fixed shaft portion.
At the same time as rotating around 10, it surely rotates integrally.

Next, the operation will be described.

When the release operation is performed, the control circuit is activated, and an exciting current is supplied to the two coils La, Lb by the drive signal of the control circuit, the stators Sa, Sb are excited, and the rotor R turns left. When the rotor R turns to the left, the shutter blade 7 turns to the right by the gear 5, and the shutter blade 8 turns to the left by the opening / closing lever 11 that turns at the same time. In this way, the shutter opening OA is gradually opened, the exposure is controlled by the combination of the aperture and the exposure time, and when the desired value is reached, the rotor R is instantaneously reversed by the drive signal of the control circuit and the shutter blade 7 and 8 turn to close the shutter opening OA.

Here, the second pin portion 15 of the opening / closing lever 11 makes the shutter blade 7
Since the outer circumference 12a of the sleeve portion 12 is fitted and engaged in the fitting hole 7d of the shutter blade 7, the play is reduced and the opening / closing lever 11 is closed. At the same time as the blade 7 rotates right, it surely rotates integrally. Therefore, the shutter aperture OA by the shutter blades 7 and 8
The opening and closing operation of is accurately performed. Therefore, highly accurate exposure control can be performed by the shutter blades 7 and 8. For example, a fixed image sensor such as a CCD is used, and the shutter blade operating device is used for a camera using a photosensitive material with a narrow latitude. be able to.

By the way, in order to assemble this shutter blade operating device, the lower plate 4 provided with the motor M is attached to the upper plate 18 provided with the fixed contact 20 and the movable contact piece 17. Next, the sleeve portion 12 of the opening / closing lever 11 is fitted into the fixed shaft portion 10, and the lower plate 4
Attach the open / close lever 11 to. Next, the fitting hole 7d and the operating groove 7b of the shutter blade 7 are fitted into the outer periphery 12a of the sleeve portion 12 of the opening / closing lever 11 and the second pin portion 15 to open the opening / closing lever 11.
Attach the shutter blade 7 to 11. Next, the second pin portion 15
Insert the operation groove 8b of the shutter blade 8 into the opening / closing lever 11
The shutter blade 8 is attached to. Since the shutter blade 7 is attached to the sleeve portion 12 and the second pin portion 15 of the opening / closing lever 11 in this manner, it is not necessary to turn over the lower plate 4 during the assembly process as in the conventional case.

[Effect of device]

As described above, according to the present invention, since one shutter blade is supported by the outer periphery of the sleeve portion of the opening / closing lever and the operating portion, the backlash is reduced and the opening / closing lever is secured at the same time as one of the shutter blades. To rotate together. Therefore, the opening / closing operation of the shutter opening by the shutter blade is accurately performed. Therefore, exposure control can be performed with high precision by the shutter blade, and the shutter blade operating device can be used for a camera using a fixed image pickup device such as a CCD and using a photosensitive material with a narrow latitude.

Further, it is not necessary to turn over the motor board during the assembly process as in the conventional case. Therefore, since the step of turning over the motor substrate can be omitted, the assembly work by the robot is simplified, the robot equipment is reduced, and the assembly time can be shortened.

[Brief description of drawings]

1 to 3 are views showing an embodiment of a shutter blade operating device according to the present invention. FIG. 1 is a front view showing a motor of this device, and FIG. 2 is a shutter blade of this device. 3 is a sectional view showing a state in which the shutter blade is supported by the outer periphery of the sleeve portion and the operating portion, and FIGS. 4 and 5 are views showing a conventional shutter blade operating device. FIG. 4 is a cross-sectional view showing a state where the shutter blade is fitted in the fixed shaft portion, and FIG. 5 is a front view showing the shutter blade of this apparatus. 7,8 ...... Shutter blade, 9,10 ...... Fixed shaft part, 11 ...... Opening and closing lever, 4 ...... Lower plate (shutter substrate), 12 ...... Sleeve part, 14 ...... First pin part (operating part) , 15: 2nd pin (actuator), OA: Shutter opening.

Claims (1)

[Scope of utility model registration request] 1. A shutter shaft that rotates around a fixed shaft to open and close a shutter opening, and a sleeve portion and an operating portion that are fitted into a shaft protruding from a shutter substrate. And a shutter opening / closing lever, wherein one of the shutter blades is supported by the outer periphery of the sleeve portion and the operating portion.