JPH0876182A - Switch device - Google Patents

Abstract

(57) [Summary] [Purpose] It is an object to provide a switch device which does not malfunction. An operation member that can be operated externally, a first power source, a second power source that is provided independently of the first power source, and a first power source are connected, and the operation member has a first power source. A first switch means that is closed when an operation amount is applied, and a second switch that is connected to a second power source and is closed when an operation amount different from the first operation amount is applied to the operation member. Means, a first connecting portion electrically connected to the first power source via a current limiting member, and a second connecting portion electrically connecting to a second power source via a current limiting member Second control means including
And a blocking means for blocking the electrical connection between the power source and the first connecting portion in the switch device.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the structure of a switch device, and more particularly to the structure of a switch device provided in a camera having a plurality of power supply systems and its peripheral devices.

[0002]

2. Description of the Related Art Conventionally, it has been known that a plurality of input members (switches) are formed in the same operation member, for example, a release button of a camera. It is also known to provide a release button on an external accessory (eg, grip device) that can be attached to and detached from the camera body. FIG. 3 is a view showing the outer appearance of the camera C equipped with the grip device G. The camera C is provided with a release button 1, and the grip device G is provided with a release button 2 and a switching operation member 3 for switching whether or not the release button 2 on the grip device side is made to function.

FIG. 4 shows a structure of a switch portion provided in the release button 2 of the grip device G. The release button 2 is provided with a half-press switch SW1 that is turned on in the first pressing step and a release switch SW2 that is turned on in the second pressing step (a step further pressed than the first pressing step). ing. Also, it is turned on in conjunction with the switching operation member 3.
A changeover switch SW3 is provided as a switch for turning off. The changeover switch SW3 is connected to GND.

The changeover switch SW3 is a release button 2
Is a switch for selecting whether or not to allow the function to function, and the release button 2 functions when the changeover switch SW3 is ON. The power supply VDD is connected to the half-press switch SW1 via a pull-up resistor R ₁ , and the power supply VCC is connected to the release switch SW2 via a pull-up resistor R ₂ .

The power supply VDD is connected to the camera C by a grip device G.
When is connected, it rises from "L" to "H". For the power supply VCC, the release button and other operation members on the camera side are operated, or the changeover switch SW3
Is ON and the half-push switch SW1 is ON, the voltage rises from "L" to "H" (that is, the power supply VCC is
It starts at a different timing from the power supply VDD).

CPU (not shown) provided on the camera C side
Is provided with an input port 1 and an input port 2. When the changeover switch SW3 is ON (center lead 5
Switch SW1 is turned on (connected to the center lead 5) (when connected to the center lead 5).
An ND level (L level) signal is transmitted to the input port 1 of the CPU. Then, the CPU supplies VCC power to each circuit of the camera, and causes the camera to perform shooting preparation operations such as photometry and distance measurement.

When the release button 2 is further pressed and the release switch SW2 is turned on (connected to the center lead 5), the GND level (L level) of the switch SW3.
The signal is transmitted to the input port 2 of the CPU. Then CP
U causes the camera to perform a series of release operations such as mirror up, diaphragm drive, and shutter drive.

[0008]

Problems to be Solved by the Invention However, FIG.
In the conventional switch device as shown in FIG. 3, even if the changeover switch SW3 is OFF, when the release switch SW2 is turned ON, the VCC “L” level signal is transmitted through the half-press switch SW1 to the input port 1 (That is, the function of the release button 2 on the grip device G side should be prohibited, but when the release button 2 is fully pressed, the same operation as that performed when the half-push switch SW1 is turned on is performed. There is a problem that the side will go).

This problem arises from the following reasons. Even if the release button 2 is pressed to turn on the half-press switch SW1 when the changeover switch SW3 is OFF, the “L” level of the switch SW3 is not transmitted to the input port 1 and the “H” level of the power supply VDD is input. It is only transmitted to port 1. Therefore, the CPU does not perform any operation.

However, when the release button 2 is further pressed to turn on the release switch SW2, the power supply VCC is "L".
The level signal is transmitted to the CPU port 1 via the switches SW1 and SW2. Then, the CPU recognizes the “L” level signal (since the CPU is configured to recognize the “L” signal = ON signal), the camera starts the same operation as when the half-push switch is turned on. Resulting in.

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above problems and provide a switch device which does not malfunction.

[0012]

In order to solve the above problems, according to the present invention, an operating member (2) which can be operated externally,
A first power source (VDD), a second power source (VCC) provided independently of the first power source, and a first power source,
The first switch means (SW1), which is closed when the first operation amount is applied to the operation member, and the second power source,
Second switch means (SW2) which is closed when an operation amount different from the first operation amount is applied to the operation member;
A first connecting portion (port 1) electrically connected to a first power source via a current limiting member (R ₁ ), and a second power source electrically via a current limiting member (R ₂ ). Means (CPU) including a second connection portion (port 2) that is electrically connected
And a blocking means (D ₁ ) for blocking the electrical connection between the second power source and the first connecting portion are configured in the switch device.

[0013]

According to the present invention, the first connecting portion and the second connecting portion of the control means are provided.
Since the electrical connection with the power supply is blocked, the control means does not transmit the power supply voltage generated by the second power supply, and the control means does not malfunction.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a diagram showing a first embodiment of the configuration of a switch device using the present invention. The same components as those in FIG. 4 are designated by the same reference numerals, and the description thereof will be omitted here. The switch device of this embodiment is also applied to the camera C and the grip device G shown in FIG.

The difference from the conventional switch device (FIG. 4) is that
A diode (Schottky diode) D ₁ is formed between the half-press switch SW1 and the pull-up resistor R _1, and a diode (Schottky diode) D ₂ is formed between the release switch SW2 and the pull-up resistor R _2. Is. Half-press timer (not shown)
After that, even if the half-press operation is released, VCC, VDD
When the timer for controlling the power supply to the camera is off, the power is supplied only from the power supply VDD (the power is not supplied from the power supply VCC), and the power is consumed by the camera. It is configured so that the electric power can be made as small as possible.

Next, the operation of the first embodiment will be described. FIG.
(A) is a figure which shows a circuit structure when the grip device G is attached to the camera C. At this time, changeover switch SW3
Is turned off, and the release button 2 of the grip device G is set so as not to function. Figure 1 (b)
Shows a state in which the release button 2 is pressed (pressed from the left side of the drawing) and the half-press switch SW1 is turned on (contacts the center lead 5). At this time, since the changeover switch SW3 is OFF, the H level of the power supply VDD is transmitted to the input port 1 (not shown) of the CPU. Therefore, the CPU does not operate, and no operation is performed on the camera side.

FIG. 1C shows a state in which the release button 2 is further pressed (further pressed from the left side of the drawing) and the release switch SW2 is turned on (contacts the center lead 5). At this time, the L level of the power supply VCC is transmitted to the Schottky diode D ₁ via the pull-up resistor R ₂ , Schottky diode D ₂ , switch SW2, and switch SW1. But this Schottky diode D
_{At 1} , the L level of power supply VCC is blocked from being transmitted to input port 1. Therefore, the CPU does not malfunction.

The power supply voltage of the power supply VDD is also pulled up.
Resistance R₁, Schottky diode D ₁, Switch SW
1, Schottky diode D via switch SW2
₂Be transmitted to. But this Schottky diode D₂
The power supply voltage of the power supply VDD is transmitted to the input port 2 at
Improper supply voltage is
The CPU may malfunction or the circuit may malfunction.
There is no fear of

In the first embodiment, an electric component (diode) is formed as a structure for preventing malfunction, so that
Since the cost can be reduced and the mounting area can be reduced as compared with the second embodiment which constitutes a mechanical switch part described later, the overall size of the device can be reduced. FIG. 2 is a diagram showing a second embodiment of the switch device using the present invention.

The difference between the first embodiment and the second embodiment is that the first embodiment constitutes an electrical component (diode), whereas the second embodiment is a mechanical switch. SW
4 is a point that is configured. The mechanical switch SW4 is provided between the half-press switch SW1 and the input port 1. The mechanical switch SW4 is a switch that turns ON / OFF in conjunction with the changeover switch SW3, and is configured so that if the switch SW3 is OFF, the switch SW4 is also OFF.

By configuring the mechanical switch SW4 in this way, when the changeover switch SW3 is turned off, the connection between the input port 1 and the half-press switch SW1 is always cut off.
Therefore, when the switch SW3 is turned off, there is no possibility that the output level (L level) from the power supply VCC will be input to the input port 1, and a safe switch device that does not cause a malfunction can be provided. In each of the above embodiments, the input ports 1 and 2 have the same CP.
Although provided in the U, the present invention is not limited to this, and the ports 1 and 2 may be configured as separate CPUs. In this case (in the case of a switch device in which ports 1 and 2 form separate CPUs), the two power supplies VCC and VDD are
Those that generate different power supply voltages may be used.

[0022]

According to the invention of claim 1, since the electrical connection between the first connecting portion of the control means and the second power supply is blocked, the power supply voltage generated by the second power supply is transmitted to the control means. The control means does not malfunction.
According to the second aspect of the invention, the electrical connection between the second power source and the first connecting portion is blocked regardless of the selection result of the selecting means, so the power source generated by the second power source in the control means. The voltage is not transmitted, and the control means does not malfunction.

According to the third aspect of the invention, since the blocking means is a mechanical switch, the electrical connection between the second power source and the first connection portion is reliably cut off, which may cause a malfunction in the control portion. It can be a safe switch device. According to the invention of claim 4, since the blocking means is an electric component, it is possible to reduce the cost and downsize the entire device as a result of the reduction of the mounting area as compared with a mechanical switch.

According to the invention of claim 5, since the blocking means for blocking the electrical connection between the second connecting portion and the first power source is further configured, the power source voltage is fed to the incorrect time or place. There is no risk of malfunction of the control unit or failure of the circuit. According to the sixth aspect of the invention, since the blocking means is an electric component, the cost can be reduced and the overall size of the device can be reduced as the mounting area is reduced as compared with a mechanical switch.

According to the invention of claim 7, since the electric component is a Schottky diode, the forward voltage drop of the Schottky diode is smaller than that of an ordinary (other) diode. Even with the configuration, it is possible to suppress the potential difference from before the insertion.
According to the eighth aspect of the invention, since the control means is one control device, the size of the entire device can be reduced.

According to the invention of claim 9, since the control means is composed of two control devices, when only one of the control devices needs to be operated, the power supply to the other control device can be stopped, and the consumption is reduced. The power can be reduced. Claim 1
According to the invention of No. 0, different control operations can be performed by continuous operation on one operation member, the number of parts can be reduced, the device can be downsized, and the cost can be reduced. The device can be easily used.

According to the eleventh aspect of the present invention, since the power supply rise timing (that is, the power supply start timing) is made different for each power supply, only the power supply necessary for the required operation is started up and unnecessary power supply is started up. You can turn it off and save power. According to the invention of claim 12,
Displacement only when operating and returning to the original state when the operation is released The self-resetting switch is configured as a switch that can be turned on only for a moment, and even if the operation is released, the displacement will be returned unless the operation is returned to the original. Since the displacement state maintaining type switch that keeps maintaining the state is configured to be a switch that needs to be kept ON for a set period, it is possible to provide a switch device that is easy to use.

[Brief description of drawings]

FIG. 1 is a circuit diagram of a switch device according to a first embodiment of the present invention.

FIG. 2 is a circuit diagram of a switch device according to a second embodiment of the present invention.

FIG. 3 is an external view of a camera equipped with a grip device.

FIG. 4 is a circuit diagram of a conventional switch device.

[Explanation of symbols]

SW1 Half-press switch SW2 Release switch SW3 Changeover switch SW4 Mechanical switch VDD First power supply VCC Second power supply R ₁ , R ₂ Pull-up resistance D ₁ , D ₂ Schottky diode

Claims (12)

[Claims] 1. An operating member that can be operated externally, a first power source, a second power source that is provided independently of the first power source, and a connection to the first power source, and the operating member. A first switch means that is closed when a first operation amount is applied to the first switch, and a second switch that is connected to the second power source and is closed when an operation amount different from the first operation amount is applied to the operation member. Second state
Switch means, a first connecting portion electrically connected to the first power source via a current limiting member, and a first connecting portion electrically connected to the second power source via a current limiting member. A switch device comprising: a control unit including two connecting portions; and a blocking unit that blocks electrical connection between the second power source and the first connecting unit. 2. The control means can execute a specific control according to an operation amount to the operation member, and whether the control means permits the specific control according to the operation. Further comprising a selection means for selecting whether or not, the blocking means, regardless of the selection result of the selection means,
The switch device according to claim 1, wherein the blocking is performed. 3. The switch according to claim 1, wherein the blocking means is a mechanical switch means provided between the first switch means and the first connecting portion. apparatus. 4. The blocking means is an electric component provided between the first switch means and the first connecting portion in a direction for blocking signal transmission from the first switch means. The switch device according to claim 1, wherein the switch device is a switch device. 5. The voltage generated by the first power supply and the voltage generated by the second power supply are different from each other at least at a certain point of time, and the electrical connection between the second connection portion and the first power supply is different. The switch device according to claim 1, further comprising a blocking unit that blocks a physical connection. 6. The blocking means is an electrical component provided between the second switch means and the second connecting portion in a direction for blocking signal transmission from the second switch means. The switch device according to claim 5, wherein the switch device is a switch device. 7. The switch device according to claim 4, wherein the electric component is a Schottky diode. 8. The switch device according to claim 1, wherein the control means is one control device including the two connecting portions. 9. The control device according to claim 1, wherein the control means includes a first control device having the first connection portion and a second control device having the second connection portion. Switch device. 10. The switch device according to claim 1, wherein the second switch means is in a closed state when an operation amount larger than the first operation amount is applied to the operation member. 11. The second power supply is turned on after the first power supply is turned on.
Switch device according to. 12. The switch device according to claim 2, wherein the first and second switch means are momentary switches, and the selection means is an alternate switch.