JPH09269542A - Pressure plate structure for camera - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pressure plate structure for a camera capable of easily loading a detecting means for optically detecting film travel with a small number of parts, and capable of making a display means for displaying camera information large in size. SOLUTION: In the camera body, the pressure plate 51 is arranged behind the film, and behind the pressure plate 51, a liquid crystal display panel 31 for displaying the camera information is fixed with a circuit substrate 41 interposed, and a panel window 25 for fitting and fixing the liquid crystal display panel 31 is installed on a body cover 11, besides, optical sensors 61 and 62 for detecting passing of film perforations are loaded on the circuit substrate 41, and sensor windows 54a and 54b corresponding to the optical sensors 61 and 62 are formed on the pressure plate 51.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pressure plate of a camera and its peripheral structure.

[0002]

2. Description of the Related Art An optical sensor is used as a means for optically detecting the running and feeding of a film when the film is wound on a camera. Conventionally, an opening is formed in a portion between an inner rail and an outer rail that guides the traveling of the film, and an optical sensor is attached to this opening.

However, since various parts are mounted on the camera body, it is difficult to secure a space for installing the optical sensor, and it is necessary to prevent the light shielding property from being impaired. Therefore, in order to install the optical sensor, the installation position,
There were many restrictions such as the shape, and the structure of the camera body was sometimes restricted by the optical sensor.

Conventionally, on the back surface of the camera body,
There were small display panels such as the date display panel,
Large display panels that display camera information such as shutter speed, aperture value, number of shots, and exposure mode are rarely mounted because of the complicated structure of the biasing spring and the light shielding structure.

[0005]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems of the conventional camera, and provides a pressure plate structure for a camera in which a detecting means for optically detecting the running of a film can be easily mounted with a small number of parts. It is an object of the present invention to provide a pressure plate structure for a camera capable of increasing the size of display means for displaying camera information.

[0006]

SUMMARY OF THE INVENTION The present invention that achieves this object is made by focusing on the space behind the pressure plate of the camera. The invention according to claim 1 is a pressure plate arranged on the back surface of the film in the camera body, and on the back surface of the pressure plate,
A display panel for displaying camera information is fixed with a circuit board in between, and a display window corresponding to the display panel is provided on the camera body or the back cover. Claim 2
The invention described in (1) is characterized in that an optical sensor means for detecting passage of perforation of a film is mounted on the circuit board, and a sensor window corresponding to the optical sensor means is formed on the pressure plate.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings. FIG. 3 is an external perspective view of an embodiment of a lens shutter type camera to which the present invention is applied. In this lens shutter type camera, the film is normally completely stored in the film cartridge, and when the film is loaded in the camera, the film is sent out from the film cartridge to take a picture (exposure).
The camera is a film cartridge compatible camera that is completely pulled back into the film cartridge when shooting is completed.

On the back surface of the body cover 11, a switch button 15 for selecting a camera function such as a viewfinder eyepiece window 13, a mode button, a drive button, a flash button and an image button.
Further, a liquid crystal display panel (LCD panel) 31 for displaying the shutter speed, aperture value, number of shots, selected camera function, etc. is mounted. Reference numeral 17 is a cartridge lid for opening and closing the film cartridge chamber, and reference numeral 19
Is an operation button for unlocking the cartridge lid 17.

Main parts of the embodiment of the present invention applied to the lens shutter type camera shown in FIG. 3 will be described with reference to FIGS. 1 and 2. 1 is an exploded perspective view of a main part of the same embodiment, and FIG. 2 is a section line II of the embodiment of FIG.
It is a sectional view taken along line -II.

An aperture frame 21 having an aperture 21a for determining a photographing screen is fixed in the body cover 11, and the aperture frame 21 has an aperture 21a.
A pair of inner rails 22a, 22b and outer rails 23a, 23b extending in the traveling direction of the film are integrally formed outside a. Further, fixed rails 24a, 24b are formed outside the outer rails 23a, 23b in parallel with the outer rails 23a, 23b. A fixing groove 56 formed in the pressure plate 51 is formed on the guide rails 24a and 24b.
The a and 56b are fitted together to fix the pressure plate 51 and prevent light from entering. Furthermore, the outer rail 23
The pressure plate 51 contacts the a and 23b, and the edge portion (perforation) of the film F passes through the tunnel space formed between the pressure plate 51 and the inner rails 22a and 22b.

The liquid crystal display panel 31 is fixed to the back surface of the pressure plate 51 with the circuit board 41 interposed therebetween. Liquid crystal display panel 3
1 is a liquid crystal panel 35, a box-shaped liquid crystal panel holder 37
The liquid crystal panel holding frame 33 presses and fixes the liquid crystal panel holder 37 against the liquid crystal panel holder 37. The liquid crystal panel holding frame 33 has four engaging projections 37a, 37a (only two of which are shown on one side shown) of the engaging claw 33a, which are provided on at least a pair of opposing side surfaces of the liquid crystal panel holder 37. The engagement hole 33a is engaged and locked.

The liquid crystal panel holder 37 is fixed to a boss 55 protruding from the pressure plate 51 by a screw 57 screwed into a screw hole of the boss 55, with the circuit board 41 being sandwiched between the liquid crystal panel holder 37 and the pressure plate 51. .

A connector 43 having a plurality of contacts is mounted on the circuit board 41, and the connector 43 projects from a connector hole 39 formed in the liquid crystal panel holder 37 and contacts a contact group of the liquid crystal panel 35. However, since the liquid crystal panel holding frame 33 presses and fixes the liquid crystal panel 35, the electrical connection between the contacts of the liquid crystal panel 35 and the contacts of the circuit board 41 is firmly secured. The connector 43 is
It is connected to a display control circuit (for example, a microcomputer) via a conductive portion formed on the circuit board 41.

The circuit board 41 is further formed with two overhanging portions 41a and 41b. The overhanging portions 41a and 41b are formed.
Optical sensors (photoreflectors) 61 and 62 are attached to b as optical sensor means for detecting the running of the film. In the optical sensors 61 and 62, the light projecting / receiving unit 62a (only one of the optical sensors 62 is shown in FIG. 2) has the projecting units 41a and 41b.
It is directed to the (circuit board 41). On the other hand, the overhang part 4
1a and 41b include light emitting / receiving sections 62 of the optical sensors 61 and 62.
An opening 41c is formed in a portion facing a. In addition,
The optical sensors 61 and 62 may be mounted on the surface of the circuit board 41 on the pressure plate 51 side. With this configuration, the circuit board 41 need not be provided with an opening. Further, the structure of the optical sensors 61 and 62 is not limited, and any one may be used.

In the pressure plate 51, the overhanging portions 41a and 41b and the sensor concave portions 53a into which the optical sensors 61 and 62 fall.
53b and the bottoms of the sensor recesses 53a and 53b,
Sensor windows 54a and 54b are formed so that the light emitting and receiving portions 62a of the optical sensors 61 and 62 face the film through the openings 41c. The sensor windows 54a and 54b are provided on the inner rail 22.
It is located between a and the outer rail 23a. The optical sensors 61 and 62 are sandwiched between the sensor recesses 53a and 53b and the liquid crystal panel holder 37, and are fixed in a state of shielding the sensor windows 54a and 54b. Further, in the pressure plate 51, fixing grooves 56a and 56b extending in parallel with the outer rails 23a and 23b are provided at portions projecting outward from both outer rails 23a and 23b.
Are formed. The fixing grooves 56a and 56b are fitted in the guide rails 24a and 24b in a light-tight state.

The optical sensors 61 and 62 are mounted on the rail 22.
The perforation of the film F traveling along the rail between a and 23a is detected. The outputs of the optical sensors 61 and 62 are input to a control circuit as is well known, and the control circuit detects the passage of perforations based on the change of the output, and counts the number of passages to measure the running amount of the film. The measurement result shows the first frame when loading,
The number of frames to be photographed or the number of frames that can be photographed is displayed on the liquid crystal display panel 31.

The body cover 11 includes a liquid crystal display panel 3
A panel window 25 for mounting 1 is formed. The panel window 25 has a stepped portion 2 on the inner peripheral edge thereof.
6 is formed, and a transparent protective cover 27 for protecting the liquid crystal panel 35 is fitted and fixed to the step portion 26 of the panel window 25.

As described above, in this embodiment, since the liquid crystal display panel is mounted on the pressure plate 51 and the liquid crystal display panel is shielded from light, the space behind the pressure plate can be effectively used, and the large size of the camera can be achieved without increasing the volume of the camera. It became possible to install a liquid crystal display panel. Further, with this configuration, the pressure plate 51
Since it is possible to provide the optical sensors 61 and 62 for detecting the running of the film, it becomes easy to install the optical sensors 61 and 62. In addition, the liquid crystal display panel and the optical sensors 61 and 62 can be installed on the same circuit board, which facilitates wiring.

The present invention has a structure suitable for a camera without a back cover, in which the pressure plate is fixed, but can be applied to a camera with a back cover. In this case, the circuit board 41 is attached to the pressure plate 51.
And the circuit board and the liquid crystal display panel 31 are connected via a flexible zebra connector. The pressure plate 51 is
Attach it to the back cover via a spring.

[0020]

As is clear from the above description, the present invention
A pressure plate arranged on the back surface of the film in the camera body, and a display panel for displaying camera information is fixed to the back surface of the pressure plate with a circuit board interposed therebetween, and the camera body or the back cover corresponds to the display panel. Since the display window is provided, a large display panel can be mounted using the space behind the pressure plate. Further, in the invention according to claim 2, since the optical sensor means for detecting the passage of the perforation of the film is mounted on the circuit board and the sensor plate corresponding to the optical sensor means is formed on the pressure plate, the optical sensor means is provided. Installation has become easier. According to the invention described in claim 4, since the optical sensor means is housed in the recess having the sensor window of the pressure plate and is fixed and shielded by being sandwiched between the pressure plate and the panel holder, the optical sensor means can be easily installed. And, the number of parts decreased.

[Brief description of drawings]

FIG. 1 is an exploded perspective view showing essential parts of an embodiment to which the present invention is applied.

FIG. 2 is a cross-sectional view taken along the section line II-II in FIG. 1, showing the same embodiment in a longitudinal section in an assembled state.

FIG. 3 is a perspective view showing an embodiment of a camera to which the present invention has been applied.

[Explanation of symbols]

 11 Camera Body 21 Aperture Frame 25 Panel Window 31 Liquid Crystal Display Panel 33 Liquid Crystal Panel Holding Frame 35 Liquid Crystal Panel 37 Liquid Crystal Panel Holder 41 Circuit Board 51 Pressure Plate 54a Sensor Window 54b Sensor Window

Claims (4)

[Claims] 1. A pressure plate disposed behind a film in a camera body, wherein a display panel for displaying camera information is fixed to the back surface of the pressure plate with a circuit board sandwiched between the pressure plate and the camera body or the back cover. A pressure plate structure for a camera, comprising a display window corresponding to the display panel. 2. The pressure plate structure for a camera according to claim 1, further comprising optical sensor means for detecting passage of perforation of a film mounted on the circuit board, and a sensor window corresponding to the optical sensor means on the pressure plate. A pressure plate structure for a camera, characterized in that 3. The pressure plate structure for a camera according to claim 1, wherein the display panel is a liquid crystal display panel, and the liquid crystal display panel is housed in a recess formed in a peripheral portion of the pressure plate. The pressure plate structure of the camera, which is characterized in that 4. The pressure plate structure for a camera according to claim 1, wherein an optical sensor window of the pressure plate is formed in a concave portion formed in the pressure plate, and the optical sensor means includes: A pressure plate structure for a camera, which is housed in a concave portion of the pressure plate and is sandwiched between the pressure plate and a panel holder of a liquid crystal display panel to be fixed and shielded from light.