JPH07244327A - Camera - Google Patents

Abstract

PURPOSE:To effectively prevent light from being leaked from a through-hole on a circuit board to a pressing plate side and to shield the light in a back cover unit with the simple constitution by arranging a light shielding plate proximately to the circuit board. CONSTITUTION:A back cover unit 20 is provided with the pressing plate 21, the circuit board 22 arranged on the back surface side of the pressing plate 21, a light shielding 'Mylar(R)' 23 functioning as the light shielding plate arranged on the back surface side of the circuit board 22, and a back cover 24. A wall part 21a is formed on the periphery of the back surface of the pressing plate 21 and constituted so that the light is prevented from being leaked from the peripheral part of the pressing plate 21. Many of electric parts such as a CPU, etc., are assembled with high density on the front of the pressing plate 21 besides a perforation sensor 28 and an LED 29. Many through-holes 22c are formed on the circuit board 22 in order to connect the electric parts on the front side and a point of contact on a back surface side. The light shielding 'Mylar(R)' 23 is formed in a shape covering nearly the entire of the circuit board 22 and arranged so as to come in contact with the back surface of the circuit board 22.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a camera, and more particularly to a camera having a back cover unit in which a pressure plate, a circuit board and a back cover are integrally formed.

[0002]

2. Description of the Related Art Conventionally, there is known a camera in which a circuit board on which an electric component such as an LCD for date imprinting is mounted is arranged between a pressure plate and a back cover in order to imprint the date etc. on a film at the time of feeding. Has been. FIG. 9 shows the configuration of a conventional general camera having such a circuit board.

As shown, the circuit board 1 is a back cover 2 of the camera.
And the pressure plate 3, and the circuit board 1 incorporates electrical components such as the date imprinting LCD 4 and the information displaying LCD panel 5. A display window 6, a rubber switch 7 and the like are arranged on the back cover 2. The pressure plate 3 is attached to the back cover 2 via a spring (not shown) for pressing the pressure plate 3 against the camera body 8, and a light shielding mylar 9 or the like is arranged on the back side of the pressure plate 3.

In such a conventional camera, the circuit board on which the electric parts are assembled is constructed as one unit, and is handled separately from the back cover and the pressure plate, depending on the type of camera. , It is designed to be incorporated into the camera body in combination with different types of back cover and pressure plate. Therefore, there is a problem that handling is inconvenient, and the thickness of the back cover becomes large, which hinders downsizing of the camera.

[0005]

The present applicant has previously proposed a camera including a back cover unit in which a back cover, a circuit board and a pressure plate are integrally formed. The structure of such a camera is shown in FIG.

As shown in the figure, in such a camera, a back cover 11, a circuit board 12 and a pressure plate 13 are integrally assembled to form a back cover unit 10. The back cover unit 10 shown in this figure is for a camera that uses a film cartridge having a light-shielding door that can be opened and closed, which has been proposed in recent years.The pressure plate 13 magnetically records information such as the date on the film at the time of feeding. The magnetic head 14 is incorporated. Circuit board
Electrical components such as a perforation sensor 15 and an LCD panel 16 are mounted on the back cover 12, and a display window 17 and a rubber switch 18 are mounted on the back cover 11.

Such a back cover unit is easy to handle at the time of assembling, and also convenient in terms of composing components. Further, there is an advantage that the thickness of the back cover can be reduced and the camera can be downsized.

By the way, in such a back cover unit,
Since the back cover and pressure plate are integrally configured, it is necessary to prevent light that has entered from the display window of the back cover and the mounting parts such as rubber switches from flowing around the peripheral edge of the pressure plate and leaking to the camera body side. Is relatively easy. However, when a hole for incorporating a magnetic head or the like is provided in the pressure plate, light may leak from the hole portion. Since the circuit board is arranged on the back side of the pressure plate, it is conceivable that light leakage can be prevented from other than the peripheral portion of the pressure plate by giving the circuit board a light shielding property. However, since through holes for mounting electric components are formed in the circuit board, in order to achieve light shielding by the circuit board, it is necessary to close all unnecessary through holes with solder or the like, which is troublesome.

The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide a back cover unit in which a back cover, a circuit board and a pressure plate are integrally formed, and to shield light from the inside of the back cover unit. This is to be possible with a simple configuration.

[0010]

In order to achieve the above object, the present invention provides a camera provided with a back cover unit as described above, in which a light shielding plate such as a light shielding mylar or a metal plate is arranged close to a circuit board. It is characterized by that.

In the present invention, among the electric components to be assembled on the circuit board, many mounted components such as CPU and chip components are assembled on one side of the circuit board, and the light-shielding plate is on the surface on which most of the electric components on the circuit board are not assembled. It is preferable to arrange them so as to be in contact with each other.

When a recording component such as a magnetic head for recording information such as the date on the film at the time of feeding is attached to the pressure plate with an adhesive, it is preferable to use an adhesive having a light shielding property.

[0013]

According to the present invention, since the light shielding plate is arranged close to the circuit board, it is possible to effectively prevent light from leaking from the through hole of the circuit board to the pressure plate side. It is possible to realize light shielding inside the back cover unit with a simple configuration without requiring troublesome work such as closing all the through holes.

In the present invention, most of the electric components are assembled on one side of the circuit board, and the light shielding plate is arranged so as to contact the surface of the circuit board on which most of the electric components are not assembled. It is possible to improve the light-shielding performance as compared with the case where the circuit board and the light-shielding plate cannot be brought into close contact with each other because they are located between the light-shielding plate and Further, by arranging most of the electric components on one side, the thickness of the circuit board can be reduced, so that it is possible to reduce the size of the back cover unit and thus the size of the camera.

When a recording component such as a magnetic head is assembled to the pressure plate with an adhesive having a light-shielding property,
It is possible to easily prevent light leakage from the assembly portion of the recording component.

[0016]

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

FIG. 1 is a rear perspective view of a camera according to an embodiment of the present invention. The illustrated camera 100 is a new type of film cartridge 20 recently proposed.
It is a camera using 0, and has a lens 101 on the front surface, a shutter release button 102 on the upper surface, and an eyepiece lens 103 on the upper rear surface. A bottom lid 104 is formed on the bottom surface of the camera 100 to be opened and closed when the film cartridge 200 is inserted into or taken out of the camera 100. The film cartridge 200 is moved upward from the state shown in the drawing. It is designed to be inserted into the camera 100 from the bottom side of the.

The film cartridge 200 comprises a cartridge main body 201 and a film cartridge inside the main body 201.
A spool 202 extending in the axial direction of 200 (vertical direction in FIG. 1) and rotatably supported by the main body 201 is provided.
It contains a film (not shown) wound around 2. A slit-shaped film drawing opening 203 is formed in the cartridge main body 201, and a light shielding door 204 for opening and closing the film drawing opening 203 is rotatably supported inside the main body 201. This film cartridge 200 has a blackout door 20
When 4 is closed, all the film is stored in the cartridge body 201 to keep the light shield state, and the light shield door 204
When the spool 202 is opened, the spool 202 is rotated so that the film can be taken in and out.

A back cover unit 20 is fixed to the rear side of the illustrated camera 100. The structure of the back cover unit 20 is shown in FIGS. 2 is an exploded perspective view showing a schematic configuration of the back cover unit mounted on the camera shown in FIG. 1, FIG. 3 is a partially enlarged view of the pressure plate shown in FIG. 1, and FIG. 4 shows a configuration of the circuit board shown in FIG. In the figure, (a) is a rear view, (b) is a front view, and (c) is a bottom view.

As shown in FIG. 2, the back cover unit 20 includes a pressure plate 21.
And a circuit board 22 arranged on the back side of the pressure plate,
Light-shielding mylar 23 as a light-shielding plate arranged on the back side of 22
And a back cover 24.

A wall portion 21a is formed on the rear edge of the pressure plate 21 to prevent light from leaking from the peripheral edge of the pressure plate 21, and the pressure plate 21 covers the circuit board 22 and the light shielding mylar 23. In this state, the back cover 24 is fixed with screws 25 or the like. Further, the pressure plate 21 is formed with an opening (not shown) for the magnetic head 26 for magnetically recording information such as date on a film (not shown) at the time of feeding. The magnetic head 26 is assembled as shown in FIG.
In this embodiment, in order to prevent light from leaking from the assembly portion of the magnetic head 26, the magnetic head 26 is assembled by filling the gap between the pressure plate 21 and the magnetic head 26 with a light-shielding adhesive 27. I am trying. Further pressure plate 21
As shown in FIG. 2, the opening 21b for the perforation sensor 28 and the LED 29, which are mounted on the front surface of the circuit board 22, are provided.
An opening 21c for use is formed.

As shown in FIG. 2, in addition to the perforation sensor 28 and the LED 29, a CPU 30 is provided in front of the pressure plate 21.
Many of the electrical parts such as are assembled in high density.
On the other hand, on the back surface of the circuit board 22, switch contacts 22a, contacts 22b for the zebra connector 31 (see FIG. 1), etc. are arranged,
An information display LCD panel (not shown) is attached to the back surface of the circuit board 22 via the zebra connector 31. The circuit board 22 is formed with a large number of through holes 22c for connecting the electric components on the front side and the contacts on the rear side, but in the present embodiment, the positions where the through holes 22c are formed are such as the CPU 30 that has a light shielding property. It concentrates on the back side of the parts to enhance the light blocking effect. It is also preferable that the circuit board 22 itself has a light blocking effect. For example, the circuit board 22 may be coated with a light-shielding paint, or the circuit board 22
It is conceivable that the ground layer has a three-layer structure with the ground layer sandwiched therebetween, and that the ground layer has a light-shielding property.

As shown in FIG. 2, the light shielding mylar 23 is a circuit board.
It is formed in a shape that covers substantially the entire portion of 22 and is arranged so as to contact the back surface of the circuit board 22. The light-shielding mylar 23 has switch contacts 22a provided on the back surface of the circuit board 22 and openings 23a and 23b corresponding to the contacts for the zebraco connector 31, and is a rubber switch to be mounted on the back cover 24.
32 and switch contact 22a contact and zebra connector 31
Can be connected to the contact 22b. In this embodiment, the through hole 22c of the circuit board 22 is connected to the opening 23a.
, 23b are formed at positions as far as possible from each other so as to enhance the light blocking effect.

An opening 24a for the rubber switch 32 and a display window 24b are formed in the back cover 24, and the back cover 24 is constructed integrally with the pressure plate 21, the circuit board 22, the light-shielding mylar 23, etc. To form.

The back cover unit 20 configured as described above
Is detachably attached to the camera body with screws 32 or the like. By making it removable, the magnetic head 26
It becomes easy to perform maintenance such as cleaning and focus adjustment of the optical system. In this embodiment, the pressure plate
A pin (not shown) for positioning with the camera body is formed on the front surface of 21 to prevent the magnetic head 26 from being displaced when the back cover unit 20 is reattached.

Next, a modification of the above-described embodiment will be described.
FIG. 5 is a perspective view showing a main part of a back cover of a camera according to a modification.
FIG. 6 is a vertical sectional view thereof.

Although the rubber switch 32 is used in the above-described embodiment, in this modified example, instead of the rubber switch 32, a seal 41 having a light-shielding property (a conductive rubber is attached to the surface facing the back cover 24 '). Is used). A recess 24'c for mounting the seal 41 is formed on the back surface of the light shielding lid 24 ', and a slit 24'd is formed in the recess 24'c. One end of a flexible sheet 42 having a switch contact 42a formed therein is disposed in the recess 24'c.
The other end is connected to the circuit board 22 'through the slit 24'd. The switch contact 42a is connected to the contact of the circuit board 22 'via the sheet 42, and is configured to be conducted by pressing the seal 41. Note that FIG.
Then, the illustration of the light-shielding mylar is omitted.

Although the embodiments of the present invention have been described above, the present invention is not limited to the specific modes of the embodiments. For example, the rubber switch 32 may be formed of a light-shielding material. It is possible to make various changes such that the light blocking effect may be further enhanced.

The back cover unit according to the present invention can also be applied to a camera using a conventional Patrone type 135 film, in which case the back cover unit can be opened and closed. FIG. 7 shows an aspect of the open / close type back lid unit.

The illustrated camera 100 'is a camera using a conventional Patrone type 135 film 210, and the back cover unit 20' is attached to the rear side of the camera 100 'so as to be openable and closable. The structure of the back cover unit 20 'is similar to that of the back cover unit 20 of the above-described embodiment.

[Brief description of drawings]

FIG. 1 is a perspective view of a camera according to an embodiment of the present invention viewed from the back side.

FIG. 2 is a perspective view showing a schematic configuration of a case back unit attached to the camera shown in FIG.

3 is an enlarged view showing a part of the pressure plate shown in FIG.

FIG. 4 is a diagram showing a configuration of the circuit board shown in FIG.

5 is a perspective view showing a main part of a back cover according to a modified example of the embodiment shown in FIG.

FIG. 6 is a vertical cross-sectional view of a case back according to a modification.

FIG. 7 is a perspective view of a camera having an openable back cover unit according to the present invention as seen from the back side.

FIG. 8 is a horizontal cross-sectional view showing the configuration of a case back unit that is not provided with a light shielding plate.

FIG. 9 is a horizontal cross-sectional view showing a configuration of a back cover portion of a conventional general camera in which a circuit board for date imprinting is incorporated.

[Explanation of symbols]

 1,12,22 Circuit board 2,11,24 Back cover 3,13,21 Pressure plate 7,18,32 Rubber switch 9,23 Light-shielding mylar 10,20 Back cover unit 14,26 Magnetic head 15,28 Perforation sensor 22a, 42a Switch contact 22c Through hole 29 LED 30 CPU 100, 100 'Camera 200 Film cartridge 210 Patrone film

Claims (3)

[Claims] 1. A back cover unit in which a pressure plate for supporting the back surface of the film, a circuit board on which electric components are assembled and arranged on the back side of the pressure plate, and a camera back cover are integrally configured. In the above camera, a light shielding plate is arranged close to the circuit board. 2. Many of the electric components are mounted on one surface of the circuit board, and the light shielding plate is arranged so as to contact a surface of the circuit board on which most of the electric components are not mounted. The camera according to claim 1, wherein the camera is a camera. 3. A recording component for recording information on a film at the time of feeding is attached to the pressure plate with an adhesive,
The camera according to claim 1, wherein the adhesive has a light-shielding property.