JP2515480B2 - camera - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a camera using a solar cell as a power source.

[0002]

2. Description of the Related Art In a camera, a battery is generally used as a power source for operating a photometric circuit and a circuit for displaying the photometric result.

[0003]

However, batteries are usually discarded when they are exhausted, which is not only a waste of resources but also a cause of pollution.

Therefore, the present invention has been made to solve the above problems, and its purpose is to use a clean solar cell that can be used semipermanently, and use it in a dark place as well as a bright place. There is also a camera available.

[0005]

The present invention has the following constitution in order to achieve the above object. That is, in a camera including a photometric circuit, a display device for displaying a photometric result, a circuit including a drive circuit for driving the display device, and a power supply for supplying power to the circuit, the camera is equipped with an upper cover as a power source. is equipped with a solar cell, a capacitor electromotive force of the solar battery is charged, it is deeply pushed Saishi
A shutter button that drives the shutter, is driven in conjunction with the shutter button, and when the shutter button is not pressed, connects the solar cell and the capacitor, and disconnects between the solar cell and the capacitor and the circuit, When the shutter button is pressed halfway, the solar cell and the circuit are connected via a changeover switch, and the solar cell and the capacitor and between the capacitor and the circuit are shut off, or The release switch circuit is provided with a release switch that connects the capacitor and the circuit via a changeover switch, and disconnects the solar cell and the capacitor and the solar cell and the circuit. , The solar power
While connecting the pond and the circuit, the capacitor and the
Position to cut off the circuit, and cut off the solar cell and the circuit
And the position to connect the capacitor and the circuit
A camera comprising a selector switch for switching between and . It is preferable to provide a plurality of the solar cells and connect them in series. The photometric circuit and drive circuit are C-MOS
It is preferable to configure the circuit to include a semiconductor element such as an IC having low power consumption.

[0006]

When the solar cells 15, 16 and 17 are irradiated with light and electromotive force is generated, the changeover switch 41 is set to be connected to the U contact shown in FIG. When the shutter button 18 is not pressed, the release switch 40
a and 40b are connected to the P contact of FIG.
Electromotive forces 16 and 17 charge the capacitor 28. When the shutter button is pressed halfway and the release switches 40a, 40b are connected to the Q contacts of FIG. 4, the above electromotive force is applied from the solar cells 15, 16, 17 to the photometric circuit 26, the drive circuit 27, and the liquid crystal display 23. Photometry is done,
Further, the result is displayed on the liquid crystal display 23. By further pressing the shutter button 18, the release switches 40a and 40b are connected to the R contact, and the shutter is driven to allow photographing. When shooting in a dark place where no electromotive force is generated to operate the circuit, set the changeover switch 41 to connect to the V contact of FIG.
Release the shutter release switch 4 by pressing the shutter button 18 halfway
0a and 40b are connected to the Q contacts of FIG. 4, the electric charge stored in the electrolytic capacitor 28 is discharged, and the photometric circuit 2
6. The liquid crystal display 23 operates. In this way, by using a clean and semi-permanently usable solar cell, photometry can be performed not only when it is bright but also when it is dark.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A preferred embodiment of the present invention will be described in detail below with reference to the accompanying drawings. 1 and 2, reference numeral 10 denotes a single-lens reflex camera. Reference numeral 12 denotes an upper cover of which a central portion covering a pentaprism (not shown) projects upward. The central protruding portion 14 of the upper cover 12
The solar cells 15, 16 and 17 are mounted on the upper surface and both side surfaces of the solar cell. Each of the solar cells 15, 16 and 17 is further divided into a plurality of segments, some of which are connected in series so that the required electromotive force can be obtained. Reference numeral 18 is a shutter button, 19 is a shutter speed setting dial, 20 is a winding lever, 21 is a viewfinder, and 25 is a film sensitivity designation dial. FIG. 3 shows the viewfinder 21. 22
Is a split image prism for focusing. Liquid crystal display 2 on top of viewfinder 21
3 is provided. 24 is the electrode. The liquid crystal display 23 displays overexposure (+), proper exposure (◯), and underexposure (−) depending on the result of photometry by a photometric element described later. External light is introduced into the liquid crystal display 23 as illumination light through the mirror 13 and the pentaprism. Alternatively, external light may be separately introduced by a light guide (not shown). A known photometric element such as CdS is arranged near the penta prism,
Photometry is done. In this photometric circuit, a photometric element is used on one side of the bridge circuit, and a variable resistor containing aperture, shutter speed, and film sensitivity setting information is used on the other side to form a photometric circuit that includes a detection circuit. There is. As the photometric circuit, a C-MOS IC or the like with low power consumption is used.

FIG. 4 shows a circuit diagram. 15, 16 and 17 are the solar cells. Reference numeral 26 is the photometric circuit. 27
Is a drive circuit for the liquid crystal display 23, and is composed of, for example, an LCD driver IC, and includes a photometric circuit 26 and the liquid crystal display 23
Are connected. For this driving circuit, a C-MOS IC or the like with low power consumption is used. The photometric circuit 26, the drive circuit 27, and the liquid crystal display 23 are arranged in parallel in the circuit. 28 is a large-capacity electrolytic capacitor for storing electricity. Reference numerals 40a and 40b are release switches whose connection is switched as the shutter button 18 is pushed down. The release switch 40a and the release switch 40b are driven in conjunction with each other as shown in FIG.
The release switches 40a and 40b are two-circuit, three-contact (P, Q, R) type mode changeover switches. Reference numeral 41 denotes a changeover switch, which enables switching between a circuit (U contact) connecting the Q contact of the release switch 40b to the Q contact of the release switch 40a and a circuit (V contact) connecting to the electrolytic capacitor 28. There is. The changeover switch 41 is formed so that it can be manually changed over from outside the camera by a lever (not shown). When the shutter button 18 is not pressed, the release switches 40a and 40b are connected to the P contacts. In this case,
The solar cells 15, 16 and 17 are connected to an electrolytic capacitor 28 via a charging resistor 30 and a diode 31, and both the solar cells 15, 16, 17 and the electrolytic capacitor 18, a photometric circuit 26, a drive circuit 27, a liquid crystal display. The connection to the container 23 is cut off. When the shutter button 18 is pressed halfway down, the release switches 40a and 40b are connected to the Q contacts. In this case, when the changeover switch 41 is connected to the U contact, the solar cells 15, 16 and 17 are connected to the photometric circuit 26, the drive circuit 27 and the liquid crystal display 23 side, and the electrolytic capacitor 28 is connected to the photometric circuit 26 and the drive circuit. Two
7. Not connected to the liquid crystal display 23. When the changeover switch 41 is connected to the V contact, the solar cells 15 and 1
Reference numerals 6 and 17 denote the photometric circuit 26, the drive circuit 27, and the liquid crystal display 2.
3 is not connected and the electrolytic capacitor 28 is connected to the photometric circuit 2
6, the drive circuit 27 and the liquid crystal display 23 are connected. When the shutter button 18 is pressed further, the release
The switches 40a and 40b are connected to the R contact, and the shutter is opened to take an image. FIG. 5 shows a specific example of the release switches 40a and 40b. Two sliding brushes 3 driven in conjunction with the movement of the shutter button 18 are shown.
3a, 33b and a printed circuit board 34 on which terminals P, Q, R fixedly arranged are formed. Sliding brush 33
The members a and 33b are formed to be movable by pressing the shutter button 18 through a member (not shown).

Next, the operation will be described. Solar cells 15, 1
Since 6 and 17 are attached to the upper cover 12 of the camera 10, sunlight can be effectively received. When the solar cells 15, 16 and 17 are irradiated with light and electromotive force is generated, the changeover switch 41 is set to be connected to the U contact of FIG. Measure the distance and focus. When the aperture and shutter speed are set and the shutter button 18 is pressed halfway down, release switches 40a and 40b are released.
Is connected to the Q contact of FIG. 4, and the solar cells 15, 16, 17 are connected.
The electromotive force is applied to the photometering circuit 26, the driving circuit 27, and the liquid crystal display 23 from the photometering, and photometry is performed, and the result is displayed on the liquid crystal display 23. Shutter button 1
8 is pressed, the release switches 40a and 40b are
It is connected to the contact point and the shutter is driven to enable shooting. A C-MOS IC is used for the photometry circuit 26 and the drive circuit 27.
Since a semiconductor device with low power consumption such as
It can be driven even by a small electromotive force of the solar cells 15, 16, 17.

When the shutter button 18 is not pressed, the release switches 40a and 40b are connected to the P contacts. Therefore, when the solar cells 15, 16 and 17 are irradiated with light and an electromotive force is generated, the resistance 30 and the diode 3
1, the electrolytic capacitor 28 is charged up to a potential obtained by subtracting the forward voltage of the diode 31 from the electromotive force, and stored. This storage potential is increased when stronger light is emitted and higher electromotive force is generated. On the other hand, even if the light is weak and the electromotive force is low, the diode 31 serves as a stopper in the opposite direction and the electric charge stored in the electrolytic capacitor 28 is not discharged. Therefore, the increased potential is stored while being maintained. When shooting in a dark place where no electromotive force for operating the circuit is generated, the changeover switch 41 is set to be connected to the V contact of FIG. 4, and the shutter button 18 is half-pressed to release the release switches 40a and 40b. When connected to the Q contact of FIG. 4, the electric charge stored in the electrolytic capacitor 28 is discharged, and the photometric circuit 26 and the liquid crystal display 23 operate. In this way, by using a clean and semi-permanently usable solar cell, photometry can be performed not only when it is bright but also when it is dark.

Although the present invention has been variously described with reference to the preferred embodiments, the present invention is not limited to these embodiments, and many modifications can be made without departing from the spirit of the invention. Of course.

[0012]

As described above, according to the camera of the present invention, a solar cell is used as a power source for photometry, a display device for displaying a photometric result, and a power source for a drive circuit for driving the display device. Therefore, it is possible to make it a clean and pollution-free camera, and to provide a condenser and a changeover switch to switch between the solar cell and the condenser. The display can be performed.

[Brief description of drawings]

FIG. 1 is a plan view of a camera.

FIG. 2 is a front view of a camera.

FIG. 3 is an explanatory diagram of a liquid crystal display.

FIG. 4 shows a circuit diagram.

FIG. 5 is an explanatory diagram of a changeover switch.

[Explanation of symbols]

 10 Camera 12 Top Cover 15, 16, 17 Solar Cell 18 Shutter Button 23 Liquid Crystal Display 26 Photometric Circuit 27 Drive Circuit 28 Electrolytic Capacitor 40a, 40b Release Switch 41 Changeover Switch

Claims (3)

(57) [Claims] 1. A camera comprising a photometric circuit, a circuit including a display device for displaying a photometric result and a drive circuit for driving the display device, and a power supply for supplying power to the circuit, wherein the power source is an upper part of the camera. A shutter button equipped with a solar cell mounted on a cover, equipped with a capacitor for charging the electromotive force of the solar cell, and driving a shutter when pushed deeply.
When the shutter button is not pressed, the solar cell and the capacitor are connected, the solar cell and the capacitor are disconnected from the circuit, and the shutter button is pressed halfway. When it is turned on, the solar cell and the circuit are connected via a changeover switch, and the solar cell and the capacitor and between the capacitor and the circuit are cut off, or via the changeover switch. A release switch that connects the capacitor and the circuit, and disconnects between the solar cell and the capacitor and between the solar cell and the circuit, is interposed in the release switch circuit, and the solar cell
The circuit is connected and the capacitor and the circuit are connected.
Position to shut off and shut off the solar cell and the circuit
Along with the position to connect the capacitor and the circuit
A camera having a changeover switch for changing over . 2. The camera according to claim 1, wherein a plurality of the solar cells are provided and are connected in series. 3. The photometric circuit and the drive circuit are C-MOS
The camera according to claim 1, wherein the camera is formed in a circuit including a semiconductor element such as an IC that consumes less power.