JP2000029125A - Camera - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a light-shielding function from being unstable due to the quality of work as in a conventional manner and to prevent the cause of the cost raising of a camera by surely preventing external light from entering the inside of a film path from an interstice between a pressing plate and an electric part. SOLUTION: This camera possesses the pressing plate 1 pressing film, the electric parts 4, 7a and 7b inserted into parts mounting holes 1a-1c formed on the pressing plate 1 and arranged so as to be opposed to the film and wiring boards 2d and 2e connected with the electric parts. In this case, light-shielding members 5 and 6 are arranged so as to surround the electric parts 4, 7a and 7b between a part on the outside of the part mounting holes 1a-1c on the pressing plate 1 and the wiring boards 2d and 2e.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention has a pressure plate for holding (a base surface of) a film, and inserts an electric component such as a photoreflector or a magnetic head for detecting a film position into a component mounting hole formed in the pressure plate. It relates to a camera to be arranged.

[0002]

2. Description of the Related Art In a camera, a film feeding passage is formed by a peripheral portion of an aperture in a camera body and a pressure plate, and the pressure plate faces the film passing through this passage to detect the position of the film. Electrical components (photoreflectors and magnetic heads) for reading and writing information to and reading information from the magnetic recording portion of the film
Is often attached.

For example, Japanese Patent Application Laid-Open No. 4-285946 discloses that a magnetic head is arranged in a notch formed in a pressure plate,
A camera in which a magnetic head and a substrate are connected at the back of a pressure plate has been proposed.

However, when such a configuration is adopted, a gap remains between the pressure plate and the magnetic head and the like, and light entering from the outside of the camera enters the film passage through the gap to unnecessarily remove the film. Exposure may occur. For this reason, conventionally, the gap is filled with a light shielding member such as suede to fill the gap.

[0005]

However, it is difficult to stably block light in mass production by the method of filling the gap as described above. Also, the actual work is based on the intuition of a skilled worker, and it is difficult to perform the work quickly. For this reason, the cost rises in the form of a decrease in the non-defective product rate and an increase in labor costs.

Further, since the light-shielding member is not of a stable shape like suede, it is necessary to increase a gap between the light-shielding member and other parts, and it is not possible to meet the need for downsizing the camera.

[0007]

According to the present invention, there is provided a pressure plate for holding a film, an electric component which is inserted into a component mounting hole formed in the pressure plate and is arranged to face the film. In a camera having a wiring board connected to the electric component, a light blocking member is disposed between the wiring board and a portion of the pressure plate outside the component mounting hole so as to surround the electric component. Then, the opening of the light shielding member is closed by the wiring substrate, and the light shielding member and the wiring substrate are covered by the light shielding cover member.

Accordingly, a structure is provided in which unnecessary light from outside the camera is not guided to the photographic film simply, reliably, and inexpensively as compared with the case where the gap between the component mounting hole and the electric component is filled. It becomes possible.

By forming the light-shielding member as a stable-shaped part such as a synthetic resin, it is possible to arrange the light-shielding member in a narrow space without fear of interference with other parts, thereby avoiding an increase in the size of the camera. it can.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS (First Embodiment) FIG. 1 shows the configuration of a camera according to a first embodiment of the present invention. FIG. 1 shows only a pressure plate 1 attached to the inside of the rear surface of the exterior of the camera, and only electric components and a wiring board attached to the pressure plate 1.

The pressure plate 1 forms, on the front surface thereof, a passage for feeding a photographic film (not shown) loaded in the camera together with an aperture peripheral portion of the camera body (not shown). In addition, the pressure plate 1 serves as a guide member for keeping the photographing screen of the film located in the passageway flat.

A printed wiring board 2 for forming an electric circuit for controlling the camera is fixed on a back surface of the pressure plate 1 by a double-sided tape (not shown). The printed wiring board 2 is a flexible printed wiring board having flexibility, and includes main electric components (main ICs).
3a, chip elements 3b, 3c, and a sub IC 3d), a main part 2c, a first connection part 2d connected to a back side terminal of the magnetic head 4 described later, and a perforation detection photoreflector 7a, 7b described later. The second connecting portion 2e connected to the back side terminal is formed so as to be integrally connected by a connecting portion extending in the front-rear direction as shown by a two-dot chain line in the drawing.

A magnetic head mounting hole 1c is formed through the lower portion of the pressure plate 1, and a front portion of the magnetic head 4 is inserted into the mounting hole 1c. The magnetic head 4 is fixed to the pressure plate 1 by bonding. An L-shaped notch is formed in the main part 2c of the printed wiring board 1 to avoid interference with the magnetic head 4. The magnetic head 4 is fixed to the pressure plate 1 by bonding. The terminal portion on the back side of the magnetic head 4 is soldered to a land of the first connection portion 2d of the printed wiring board 2 and connected to a main IC 3a for controlling the magnetic head 4.

Further, photoreflector mounting holes 1a and 1b are formed through the upper portion of the pressure plate 1, and front portions of the photoreflectors 7a and 7b are inserted into these mounting holes 1a and 1b. These photoreflectors 7a, 7
b is fixed to the pressure plate 1 by bonding. The main portion 2c of the printed wiring board 1 is formed with holes 2a and 2b having substantially the same shape as the photoreflector mounting holes 1a and 1b, so that interference with the photoreflectors 7a and 7b is avoided. The terminal portions on the back side of the photoreflectors 7a and 7b are soldered to the lands of the second connection portion 2e of the printed wiring board 2 and connected to the main IC 3a for controlling the photoreflectors 7a and 7b.

In the peripheral portion of the pressure plate configured as described above, the magnetic head 4 faces a magnetic recording portion (not shown) formed at the upper portion in the width direction of the film passing through the feeding passage. Thereby, it is possible to write and read magnetic information to and from the magnetic recording unit through the magnetic head 4.

Further, the photoreflectors 7a and 7b face the perforation forming portion at the lower part in the width direction of the film. When the perforations of the film face the front surfaces of the photoreflectors 7a and 7b, the light emitted from the light emitting units of the photoreflectors 7a and 7b diverge, so that the light does not enter the light receiving unit and the output becomes LOW.
On the other hand, when the perforation of the film comes off from the front surfaces of the photo reflectors 7a and 7b, the photo reflector 7
Since the light emitted from the light emitting portions a and 7b is reflected by the film surface and enters the light receiving portion, the output becomes HIGH. The main IC 3a detects the feed amount of the film and the stop position based on the change in the output state.

Next, the structure for blocking unnecessary light (shielding structure) for the film in the present embodiment will be described in detail. That is, the mounting holes 1c, 1a, 1
b and the magnetic head 4 and the photoreflectors 7a and 7b
A light-shielding structure for preventing external light from entering the feeding passage from a gap between the outer periphery and the outer periphery of the feeding passage will be described in detail. A rear portion of the magnetic head 4 (a portion protruding from the mounting hole 1c) is provided on an outer portion of the magnetic head mounting hole 1c (a portion between the mounting hole 1c and the cutout portion of the main portion 2c of the wiring board 2) on the back surface of the pressure plate 1. A light-shielding frame 5 made of synthetic resin is attached with double-sided tape or the like so as to surround the outer periphery of the portion (4). Also,
On the back surface of the light shielding frame 5, the first connection portion 2d of the wiring board 2 is provided.
Is attached with double-sided tape.

Here, the first connecting portion 2d of the wiring board 2 is
The light shielding frame 5 is formed in a shape that completely covers the opening on the rear side. Further, since the base of the wiring board 2 is a transparent member, the first connection portion 2d has an opening on the rear side of the light shielding frame 5 so as to surround a land pattern connected to the terminal of the magnetic head 4. A light-shielding pattern (hatched portion in the figure) is formed so as to cover the area. For this reason, the gap between the pressure plate 1 and the magnetic head 4 is completely covered by the light shielding frame 5 and the first connection portion 2d of the wiring board 2, and external light enters the film feeding passage through the gap. Can be reliably prevented.

On the other hand, on the back surface of the main part 2c of the wiring board 2 fixed to the pressure plate 1, an elastic member 6 made of a malt plane or the like is attached by a double-sided tape. The elastic member 6 is provided in the hole 2 on the back surface of the main portion 2 c of the wiring board 2.
a, 2b, the photoreflectors 7a,
7b has a U-shaped notch 6a and a hole 6b that surround three or four outer peripheries of the rear part (projections from the mounting holes 1a and 1b and the holes 2a and 2bc). The elastic member 6 also has a hole 6c for avoiding interference with the chip element 3b.

The second surface of the wiring board 2 is
The connection portion 2e is attached with a double-sided tape or the like.

Further, in this embodiment, the light-shielding positive cover member 8 covering the elastic member 6 and the second connecting portion 2e of the wiring board 2 is screwed to the pressure plate 1, and the elastic member 6 is compressed to exhibit the light-shielding effect. I have. In addition, a wall that covers an upper opening of the cutout portion 6a of the elastic member 6 is formed above the light-shielding cover member 8.

As described above, the pressure plate 1 and the photo reflector 7
Since the gap between a and b is sufficiently compressed and covered with the elastic member 6 having a light-shielding property and the light-shielding cover member 8, external light enters the film feeding passage through the gap. Can be reliably prevented.

As described above, according to the present embodiment, intrusion of external light into the film feeding passage from the gap formed in the magnetic head mounting portion or the photoreflector mounting portion of the pressure plate 1 is simply and reliably blocked. And exposure of the film due to external light leakage can be prevented.

In this embodiment, a case has been described in which a flexible printed circuit board having a main portion and a connecting portion formed integrally is used. However, each portion is formed of a rigid printed circuit board and connected with a connector or a flexible printed circuit board. May be used.

[0025]

As described above, according to the present invention,
By performing a simple operation of positioning and arranging a light-shielding member surrounding the electric component between a portion of the pressure plate outside the component mounting hole and the wiring board, the film path from the gap between the pressure plate and the electric component is reduced. External light can be reliably prevented from entering. Therefore, the light shielding function does not become unstable or the cost of the camera does not increase depending on the quality of work as in the related art.

If the light-shielding member is formed as a stable-shaped component such as a synthetic resin, the light-shielding member can be disposed in a narrow space without fear of interference with other components, and an increase in the size of the camera can be avoided. .

If the light-shielding member is provided with an adhesive portion, the positioning of the light-shielding member on the pressure plate can be performed more easily.

Further, if a thin flexible printed wiring board is used as the wiring board, it is possible to reduce the entire light shielding structure or to configure a light shielding structure having no variation due to mass production.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a configuration of a peripheral portion of a pressure plate of a camera according to a first embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Pressure plate 1a, 1b ... Photoreflector mounting hole 2 ... Printed wiring board 2a, 2b ... Hole 2c ... Main part 2d, 2e ... Connection part 3a, 3d ... IC 3b, 3c ... Chip element 4 ... Magnetic head 5 ... Light shielding frame 6 Elastic member 7a, 7b Photoreflector 8 Light-shielding cover member

Claims (12)

[Claims] 1. A camera comprising: a pressure plate for holding a film, an electric component inserted into a component mounting hole formed in the pressure plate and arranged to face the film, and a wiring board connected to the electric component. A camera, wherein a light blocking member is arranged between the wiring board and a portion of the pressure plate outside the component mounting hole so as to surround the electric component. 2. The camera according to claim 1, wherein the wiring board has a shape that closes an opening of the light blocking member. 3. The camera according to claim 2, wherein a light-blocking conductive pattern is formed in a portion of the wiring board that covers the opening of the light-blocking member. 4. The camera according to claim 1, wherein the light blocking member is formed of a synthetic resin. 5. The camera according to claim 1, wherein a light-shielding cover member that covers the light-shielding member and the wiring board is attached to the pressure plate. 6. The camera according to claim 5, wherein the light-shielding member shows a light-shielding property by being compressed, and the light-shielding member is compressed by the light-shielding cover member. 7. The camera according to claim 1, wherein the electric component is a sensor for detecting a position of the film in a feeding direction. 8. The apparatus according to claim 1, wherein the film includes a magnetic recording unit capable of recording magnetic information, and the electric component is a magnetic head that writes or reads magnetic information to or from the magnetic recording unit. The camera according to any one of claims 1 to 6, wherein 9. The camera according to claim 1, wherein an adhesive portion is provided on at least one of the pressure plate side and the wiring board side of the light shielding member. 10. The camera according to claim 1, wherein the wiring board is a flexible printed board. 11. A wiring board different from the wiring board is arranged on the pressure plate, and the light blocking member is arranged between the wiring board and the another wiring board. Claims 1 to 10
The camera according to any one of the above. 12. The wiring board is formed integrally with a main part disposed on the pressure plate and a connection part connected to the electric component, and the light shielding member is formed integrally with the connection part. The camera according to claim 1, wherein the camera is arranged between the camera and a main part.