JPH07295046A - Electric circuit device for camera - Google Patents

Abstract

PURPOSE:To provide an electric circuit device for a camera capable of hardly exerting torque on an FPC board, obtaining high reliability and reducing manufacturing costs. CONSTITUTION:The electric circuit device is provided with the FPC board 1 provided along the roof surface of a pentagonal prism 5, an extended part if formed as a part of the FPC board 1 and extended from its object side, a first, electrical part 3 attached to the FPC board 1 and a second electrical part 2 provided on the photographer side of the pentagonal prism 5 and attached to the extended part if and it is overlapped on the object side of the FPC board 1 to connect the first electrical part 3 to the second electrical part 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric circuit device for a camera used in a single-lens reflex camera or the like.

[0002]

2. Description of the Related Art FIG. 3 is a perspective view showing the inside of a conventional single-lens reflex camera, showing the periphery of a pentaprism constituting a viewfinder of the camera.

In FIG. 3, reference numeral 11 is an FPC board which constitutes an electric circuit of the camera. Reference numeral 15 is a pentaprism that constitutes the viewfinder of the camera. FPC board 11
Is bent along the roof surfaces 15a and 15c of the pentaprism 15, and is bent above the pentaprism 15 (FIG. 3).
It is located in. Reference numeral 11b is a circuit pattern formed on the FPC board 11. The circuit pattern 11b is FP
It is formed on both front and back surfaces of the C substrate 11. FPC board 1
The circuit patterns 11b on the front and back sides of No. 1 are electrically connected to each other. An electric component 13 is mounted on the FPC board 11 along the roof surfaces 15a and 15c. An extension 11f of the FPC board 11 is formed on the FPC board 11 near the protrusion 15d of the pentaprism 15.
Further, the light receiving element 12 is mounted on the surface opposite to the electric component 13 near the tip portion 11g of the extending portion 11f. The light receiving element 12 has a light receiving portion (not shown) inside.
The condenser lens 14 is an exit surface 15b of the pentaprism 15.
And the light receiving element 12 are fixed. Condensing lens 14
Collects the light emitted from the exit surface 15 b of the pentaprism 15 on the light receiving portion of the light receiving element 12.

[0004]

In the shape of the FPC board 11 shown in FIG. 3, the distance from the root portion 11h of the extending portion 11f to the light receiving element 12 is short. Therefore, the condenser lens 1
When the light receiving element 12 is aligned, the force acting on the FPC board 11 is extended so that the light collected by the light receiving element 12 is collected at a predetermined position of the light receiving portion of the light receiving element 12.
It becomes difficult to relax with 1f. Therefore, F
Excessive strain is generated in the root portion 11h of the PC board 11 and the light receiving element 12, and the FPC board 11 is broken or the circuit pattern 11b of the FPC board 11 is peeled off.
However, there is a problem that the reliability of the circuit is deteriorated, such as the soldered part is peeled off.

Further, the light receiving element 12 and the electric component 13 are
Since it is arranged on the opposite surface of the PC board 11, it is necessary to mount the electric component 13 or the light receiving element 12 on both surfaces of the FPC board 11. Generally, in a general-purpose automatic assembling apparatus for fixing parts on a substrate, parts can be assembled on only one surface. If you try to mount parts on a board using an automatic assembly device, you will have to use an expensive automatic assembly device that can be mounted on both sides, or it will be troublesome twice to mount and fix the parts one by one. . Therefore, there is a problem that the cost for mounting the electric component 13 and the light receiving element 12 on the FPC board 11 becomes high.

The present invention has been made in view of the above problems, and it is an object of the present invention to provide an electric circuit device for a camera, which is less likely to be twisted by the FPC board, has high reliability, and can be manufactured at a reduced cost. To aim.

[0007]

To achieve this object, an electric circuit device of a camera of the present invention is formed as an FPC board provided along a roof surface of a pentaprism, and as a part of the FPC board. The FPC board includes an extending portion extending from the subject side, a first electrical component attached to the FPC substrate, and a second electrical component provided on the photographer side of the pentaprism and attached to the extending portion. FP extension
The first electric component and the second electric component are connected by being folded back on the subject side of the C substrate.

[0008]

In the electric circuit device of the camera having the above structure,
By folding back the extension on the subject side of the FPC board, the first
Since the electric component and the second electric component are connected to each other, the length of the extending portion is increased, the extending portion is bent, or the second electric component is moved for alignment. The forces that sometimes occur can be dispersed. This gives F
Excessive force is less likely to be applied to a part of the PC board, cutting of the FPC board and peeling of the second electric component are less likely to occur, and the reliability of the electronic circuit device of the camera is improved.

Further, since the extension portion is folded back on the subject side of the FPC board, the first electric component and the second electric component are mounted and fixed on the same surface of the FPC board. As a result, the mounting work becomes efficient and the work cost can be reduced.

[0010]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a perspective view showing a first embodiment of an electric circuit device for a camera according to the present invention.

In FIG. 1, reference numeral 1 is an FPC board which constitutes an electric circuit of the camera. Reference numeral 5 is a pentaprism that constitutes a viewfinder of the camera. The penta prism 5
It may be a prism made of transparent glass or the like, or a pentagonal roof-shaped reflecting mirror whose reflecting surfaces are formed by reflecting mirrors. In the present specification, they are referred to as pentaprisms without distinguishing them.

The FPC board 1 is bent along the roof surfaces 5a and 5c of the pentaprism 5 and is arranged above the pentaprism 5 (FIG. 1). 1b is a circuit pattern formed on the FPC board 1. Circuit pattern 1
b is formed on one surface of the front surface or the back surface of the FPC board 1, and connects the electronic component 3 and the light receiving element 2. Roof 5a
The electronic component 3 is mounted on the FPC board 1 along the lines 5 and 5c. Although the FPC board 1 further extends in the left-right direction in FIG. 1, it is shown by a broken line and its description is omitted.

The FPC board 1 is formed with an extending portion 1f extending from the subject side. The extending portion 1f is folded back at the root portion 1c on the way and arranged along the roof surface 5c. The light receiving element 2 is mounted near the tip 1g of the extension 1f. The light receiving element 2 is mounted on the same surface as the electronic component 3 on the FPC board 1. The light receiving element 2 is attached and fixed in the vicinity of the protruding portion 5d of the pentaprism 5.
The condenser lens 4 is fixed between the exit surface 5b of the pentaprism 5 and the light receiving element 2.

Since the root portion 1c of the extending portion 1f of the FPC board 1 is formed on the object side in this way, the length from the root portion 1c to the light receiving element 2 becomes long, and the light receiving element in the directions of arrows A and B. When the position of 2 is adjusted, it is easier to prevent the generation of the distortion force due to the position adjustment as compared with the conventional example, and as a result, it becomes difficult for an excessive force to be generated in the light receiving element 2 and the root 1c.
Further, even when the position of the light receiving element 2 is adjusted in the directions of arrows C, D and E, the twist generated in the light receiving element 2 and the root portion 1c becomes smaller than that in the conventional example, and the light receiving element 2 and the root portion 1c are not twisted. It became difficult to generate excessive force.

Further, since the electronic component 3 and the light receiving element 2 can be mounted and fixed on the same surface of the FPC board 1, it is only necessary to mount the component on one surface, which makes the work efficient. The cost of mounting work can be reduced. Moreover, since it is not necessary to insert the terminals of the light receiving element 2 into the holes of the substrate, automatic assembly can be easily performed, and the mounting cost can be further reduced.

FIG. 2 is a perspective view showing a second embodiment of the electric circuit device of the camera according to the present invention.

In FIG. 2, the condenser lens 4 reflects the light transmitted through the projection 5d (see FIG. 1) of the pentaprism 5 upward in the middle of the condenser lens 4 to change the optical axis, and the pentaprism 5 The light receiving portion of the light receiving element 2 arranged substantially horizontally above 5 (FIG. 2) is focused.

Similar to the first embodiment described above, the FPC board 1 constituting the electric circuit device of the camera is arranged along the roof surfaces 5a and 5c of the pentaprism 5. The circuit pattern 1b is one of the front and back surfaces of the FPC board 1.
It is formed on the surface on which the electronic component 3 is fixed.

The FPC board 1 is formed with an extending portion 1f extending from the subject side. The extending portion 1f is folded back at the root portion 1c on the way, and is arranged substantially horizontally along the ridgeline of the roof surfaces 5a and 5b of the pentaprism 5. The light receiving element 2 is mounted near the tip 1g of the extension 1f. The light receiving element 2 is the FPC board 1
It is mounted on the same surface of the upper electronic component 3. The light receiving element 2 is attached and fixed in the vicinity of the protruding portion 5d of the pentaprism 5.

In the second embodiment, in addition to the effects of the first embodiment, the tip portion 1g near the light receiving element 2 is attached to the pentaprism 5.
Since it is arranged substantially along the ridgeline formed by the roof surfaces 5a and 5b, it is possible to reduce the bending of the extending portion 1f near the light receiving element 2. As a result, compared to the first embodiment, the extension portion 1f near the light receiving element 2 is less likely to be twisted, and the reliability of the electric circuit device is improved.

Further, the extending portion 1f of the FPC board 1 has the roof surfaces 5a and 5a of the penta prism 5 near the light receiving element 2.
Since the light receiving elements 2 are arranged so as to be along the ridgeline of b, the left and right of the light receiving element 2 are no longer covered by the FPC board 1. Therefore, after adjusting the position of the light receiving element 2, the left and right positions of the light receiving element 2 can be used to fix the light receiving element 2. That is, the effect of efficiently using the space can be obtained.

According to the embodiment described above, the following effects can be obtained.

FPC arranged along a pentaprism
From the substrate 1, the extending portion 1 f is provided with the protruding portion 5 of the pentaprism 5.
Since the length of the extension portion 1f is increased by extending the extension portion 1f from the opposite side, the force generated when the extension portion 1f is bent or the light receiving element 2 is moved for alignment. Can be dispersed. That is, an excessive force is less likely to be applied to the light receiving element 2 or the root portion 1c of the extending portion 1f of the FPC board 1, and the FPC board 1 is cut at the root portion 1c of the extending portion 1f, The element 2 is less likely to be peeled off and the reliability of the electronic circuit device of the camera is improved.

Further, since the electronic component 3 and the light receiving element 2 can be fixed on the same surface of the FPC board 1, it suffices to mount the components on only one surface, which makes the work efficient. . As a result, the cost of fixing the parts can be reduced. Moreover, it becomes possible to use an inexpensive automatic assembling apparatus, which facilitates the automatic assembling and further reduces the cost. Further, since the electronic component 3 and the light receiving element 2 can be arranged on the same surface of the FPC board 1, it is not necessary to use an expensive double-sided board due to the arrangement of parts as in the conventional case. lost. By devising the circuit pattern 1b, when a single-sided board can be used, an inexpensive single-sided board can be used.

Further, in the second embodiment, the extending portion 1f of the FPC board 1 in the vicinity of the light receiving element 2 is arranged along the ridge line formed by the roof surfaces 5a and 5b of the pentaprism 5, so that the light receiving element 2 and The twist generated in the root portion 1c is reduced, the reliability of the electric circuit device is further increased, and the space around the light receiving element 2 can be effectively utilized.

[0027]

As described above, according to the electric circuit device for a camera of the present invention, the extending portion is folded back on the subject side of the FPC board to connect the first electric component and the second electric component. By doing so, the length of the extension portion becomes long, and it is possible to disperse the force generated when the extension portion is bent or when the second electric component is moved for alignment.
As a result, excessive force is less likely to be applied to a part of the FPC board, cutting of the FPC board and peeling of the second electric component are less likely to occur, and the reliability of the electronic circuit device of the camera can be improved. Becomes

Further, since the extending portion is folded back on the subject side of the FPC board, the first electric component and the second electric component are mounted and fixed on the same surface of the FPC board. As a result, the mounting work becomes efficient and the work cost can be reduced.

[Brief description of drawings]

FIG. 1 is a perspective view showing a first embodiment of an electric circuit device of a camera according to the present invention.

FIG. 2 is a perspective view showing a second embodiment of the electric circuit device of the camera according to the present invention.

FIG. 3 is a perspective view showing an example of an electric circuit device of a conventional camera.

[Explanation of symbols]

 1 FPC board 1b Circuit pattern 1c Root part 1f Extended part 1g Tip part 2 Light receiving element 3 Electronic component 4 Condensing lens 5 Penta prism 5a Roof surface 5b Roof surface 5c Roof surface 5d Projection portion

Claims (7)

[Claims] 1. An FPC board provided along a roof surface of a pentaprism, an extending portion formed as a part of the FPC board and extending from a subject side of the FPC board, and attached to the FPC board. A first electric component and a second electric component provided on the photographer side of the pentaprism and attached to the extending portion, and by folding the extending portion on the subject side of the FPC board, An electric circuit device for a camera, wherein the first electric component and the second electric component are connected. 2. The electric circuit device for a camera according to claim 1, wherein the second electric component is a light receiving element that receives light emitted from the emission surface of the pentaprism. 3. The electric circuit device for a camera according to claim 2, wherein the first electric component and the second electric component are mounted on the same surface of the FPC board and the extending portion. 4. The electric circuit device for a camera according to claim 3, wherein the extending portion is folded back along the roof surface of the pentaprism on the subject side of the FPC board. 5. The electric circuit device for a camera according to claim 4, wherein the second electric component is attached near the tip of the extending portion. 6. The electric circuit device for a camera according to claim 3, wherein the extending portion is folded back along the ridgeline between the roof surfaces of the pentaprism on the subject side of the FPC board. 7. The electric circuit device for a camera according to claim 6, wherein the second electric component is attached near the tip of the extending portion.