JPH0712983Y2 - Imaging device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field of the Invention) The present invention relates to a photographing apparatus that can miss a shutter chance and save current consumption of the entire apparatus.

(Background of the Invention) A photographing device that starts power supply to a photometric circuit at the same time as the half-press switch is turned on to perform a photometric operation is known from Japanese Patent Laid-Open Nos. 57-74733 and 58-48832. .

However, these conventional devices do not provide accurate photometric output at the same time as power is supplied to the photometric circuit (at the same time when the half-press switch is turned on). It is configured to obtain the output.

Therefore, the half-push switch and the release switch are turned on at the same time.
However, the shooting operation (shutter release) cannot be performed until the output of the photometry circuit becomes stable, and there is a risk that the photo opportunity will be missed.

In addition, conventionally, it is known that when a motor drive device is attached to a camera, electric power is supplied from the motor drive device to the camera side.

A structure in which a minute current always flows from the power source of the motor drive unit to the latch release circuit of the photometric circuit of the camera side and the oscillation circuit of the exposure control circuit even when the motor drive unit is powered off from the time of installation. I was told.

However, since a small amount of current is constantly applied from the time of mounting, the power source of the motor drive device is consumed quickly.

(Purpose of the Invention) In view of these drawbacks, the present invention allows the photographing operation to be performed immediately even if the release switch is pressed immediately after the half-press switch is pressed, so that a photo opportunity is not missed.
Another object of the present invention is to provide a photographing device that can effectively use a power source.

(Embodiment) FIGS. 1 to 6 show a preferred embodiment of the present invention.
FIG. 1A is a front view of the motor drive device,
FIG. 2B is a plan view of the motor drive device.
FIGS. 3 and 4 are cross-sectional views of the grip portion of the motor drive device, and FIGS. 4 and 5 are A of FIGS. 2 and 3.
FIG. 6 is a sectional view taken along arrow A, and FIG. 6 is a circuit diagram of the motor drive device.

The S / C ring 1 shown in FIGS. 1 (a) and (b) is engraved with the letters L, S, C, and when L is aligned with the fixed index (Y) (hereinafter abbreviated as L position). It becomes impossible to mechanically lock and press the release button 2, and when S or C is aligned with the index (Y) (hereinafter, S position or C
The release button 2 can be pressed to the position (abbreviated as position), and the release button 2 is pressed halfway (that is, electric power on the motor drive side is supplied to the camera side to operate the exposure control circuit and the like of the camera) and the release. It is possible to perform an operation (that is, the shutter curtain is run to take an image of proper exposure, and the automatic film winding operation is completed at the end of the image taking). Motor drive device S / C ring 1 is L
When it is set to the position, the release button 2 is locked and the power is cut to block the power supply. Therefore, the exposure control system does not work even on the camera side and the electromagnetic release cannot be performed. Also, when the S / C ring 1 is set to the S position, the release button 2 is unlocked and power supply is started, so the circuit on the camera side also works and the electromagnetic release becomes possible and the shooting is completed. Then, the motor drive device operates and film winding is completed. When the C position is set, in addition to the operation at the S position described above,
Pressing the release button 2 enables continuous shooting.

The operation of the S / C ring 1 and the release button 2 described above will be described in detail. A groove 2a is formed in the release button 2 in the grip portion shown in FIG.
At the position, since the locking member 3 has entered the groove 2a, the release button 2 cannot be pushed. Further, as shown in FIG. 3, at the S position and the C position of the S / C ring 1, the lock member 3 is retracted from the groove portion 2a, so that the release button 2 can be pushed and the manual pushing operation and the releasing operation are possible. It is in a state of That is, as shown in FIGS. 4 and 5, the S / C ring 1
Is in the L position, the pin 4 fixed to the lock member 3
Is pressed against the cam 5 by the force of the urging spring 6, and the lock member 3 enters the groove 2a. When the pin 4 is in the S and C positions, the pin 4 is pressed by the cam 5 to the force of the urging spring 6. Thus, the lock member 3 is retracted from the groove 2a.

Therefore, as shown in FIGS. 2 and 3, the release button 2
Half-push switch member with the first stroke when pushing down
7, 8 are brought into contact with each other to perform a half-press operation, and in the next second stroke, a release switch constituted by a micro switch or the like (not shown) further below is turned on to perform a release operation.

Next, the electrical operation and configuration of the motor drive device and the camera will be described with reference to FIG.

As shown in FIG. 6, when the motor drive device is mounted on the camera, the contacts 11 to 16 of the motor drive device are connected to the contacts 11 'to 16' on the camera side, respectively. And by connecting the contacts 12 and 12 ', the power switch SW.1B in the camera is
It is connected to the O contact side so that the power supply e1 on the camera side is cut and power is supplied from the motor drive device to the camera side.

A case where the above-mentioned S / C ring 1 is set to the L position will be described. Since the S / C ring 1 is set to the L position, the minute current supply switch SW.1 is turned off in conjunction with the S / C ring 1. At this time, since the release button 2 is not mechanically pressed as described above, the half-press switch SW.2 and the release switch SW.3 are off. As a result, unless the half-press switch SW.2B on the camera side is turned on, the transistor TR1 of the motor drive device is off, the first constant voltage circuit A1 does not operate, and the motor control circuit A2 does not operate either. Therefore, the current consumption from the power source E of the motor drive device is zero. Therefore, the minute current supply switch SW.1 is turned off by interlocking with the SC ring 1, so that the power source E, the resistor R1, and the diodes D1 to D5.
Since a closed circuit is not created by, the current consumption can be reduced to zero.

Next, when the S / C ring 1 is set to the S position, S / C
Linked with ring 1, minute current supply switch SW.1 is ON,
Also, S / C switch SW.4 is turned on. Therefore, the power supply E, the resistor R1, and the diodes D1 to D5 form a second constant voltage circuit (closed circuit) to allow current to flow, and the connection point between the resistor R1 and the diodes D1 to D5 connected in series. (A) is a constant voltage
Va is generated, and its voltage Va contacts via diode D8.
Supply constant voltage V ₂ from 12,12 'to the camera side. And
Through the power source switching switch SW.1B and the resistor r3, (the resistor r3, the transistor Tr2, the transistor Tr2, which is composed of the silicon photo diode S, the diode d4 and the head amplifier a1)
The preset capacitor C of the latch release circuit (composed of the capacitor C) is charged. At this time, before the shutter release, the amount of electric power supplied from the motor drive device to the camera side is only the charging current of the capacitor C, and the charging current may be a minute current. Therefore,
The current flowing in the closed circuit formed by the second constant voltage circuit (power supply E, resistor R1, diodes D1 to D5) can be set to a minute current.

When the photographer starts photographing and presses the release button 2, the members 7 and 8 shown in FIGS. 2 and 3 come into contact with each other and the half-press switch SW.
2 turns on. The half press switch SW.2 is turned on, the transistor TR1 actuates the first constant voltage circuit A1 is turned on, to generate a constant voltage E _2. This constant voltage E ₂ is applied to the camera side as a constant voltage V ₂ ′ via the diode D7 and the contacts 12, 12 ′. Also, by turning on the half-press switch SW.2,
The signal transmitted from the contacts 15 and 15 'to the camera side turns on the transistor Tr1 in the camera, and the constant voltage
V ₂ ′ is applied to the exposure control circuit a2 of the camera via the emitter collector of the transistor Tr1. At the same time, when the transistor Tr1 is turned on, the transistor Tr2 is turned on via the resistor r4, and the electric charge stored in the capacitor C of the latch release circuit is discharged via the diode d3. Therefore, when power is supplied, the electric charge accumulated in the inverting input terminal of the head amplifier a1 of the photometric circuit is quickly drawn into the capacitor C and discharged through the transistor Tr2. As a result, the silicon photodiode S of the photometric circuit
Output signal can be stabilized, the output of the head amplifier a1 can also be stabilized, and an accurate photometric output can be provided.

When the release button 2 is further pressed and the release switch SW.3 is turned on, the release circuit A3 operates and the contacts 14,14 '
The exposure control circuit a2 in the camera is operated via. Then, as described above, the photometric output signal from the head amplifier a1 of the photometric circuit is input to the exposure control circuit a2 for exposure calculation, and the circuit a2 operates so that the shutter curtain and the diaphragm blade are properly exposed. Then, when the release operation is completed, the winding switch SW.4B is turned on, the ON signal is transmitted to the motor control circuit A2 via the contacts 16 and 16 ', and the motor M winds up one frame of film. When the film is completely wound, the winding switch SW.4B is turned off and the motor M is stopped. At this time, as described above, the S / C ring 1 is in the S position and the S / C switch SW.4 is on. Therefore, the release circuit A3 is configured so that the next release operation cannot be performed as long as the release switch SW.3 in the motor drive device is pressed.
After that, when the photographer releases the release button 2, the half-press switch SW.2 and the release switch SW.3 are turned off, but the exposure control circuit a2 in the camera turns the half-press switch SW.2 off. This does not stop the operation, but rather the diode.
Tr1 is turned on for an arbitrary time T (about 16 seconds) via d2, and transistors TR1 and TR2 in the motor drive device are turned on via contacts 11 and 11 'to generate the first constant voltage circuit A1.
Is operated to apply the voltage V ₂ ′ to the exposure control circuit a2.

Next, the case where the S.C ring 1 is set to the C position will be described. Since the operation is almost the same as the case of the S.C ring 1 set to the S position described above, only different operations will be described. . When the S / C ring 1 is set to the C position, the S / C switch 1SW.4 is turned off, and the other switches are the same as in the S position. The photographer presses the release button 2 to press the half-press switch S of the motor drive device.
When W.2 and release switch SW.3 are turned on, shooting is performed and the film is wound up by one frame as described above. After that, if the photographer continues to press the release button 2 without releasing the release button, shooting is continuously performed.
This is different from the position. This means that the release circuit A3 turns the hoist switch by turning off the S / C switch SW.4.
The exposure control circuit a2 is continuously operated to perform the release operation in association with the turning off of SW.4B (film winding completion).

Therefore. If the photographer continues to press the release button 2, continuous photography is possible. The half-push switch SW.2B and the release switch SW.3B on the camera side are the half-push switch SW.2 and the release switch SW.3 of the motor drive device.
It has the same function as.

Therefore, in the present embodiment, when the motor drive device is mounted on the camera for photographing, the S / C ring 1 is selected at the S or C position. At this time, switch for supplying a small current
Since SW.1 is turned on, and the preset capacitor C of the latch release circuit in the camera is sufficiently charged by the second constant voltage circuit between the selection of the S / C ring 1 and the actual photographing, In addition, when the shutter is released, that is, when the half-press switch SW.2 is turned on, the operation of the photometry circuit described above is stably performed, and the release operation is also accurately operated. Therefore, it is not necessary to constantly supply a minute current to the preset capacitor C as in the conventional case.
A minute current supply switch SW.1 is provided in the second constant voltage circuit. By connecting the switch SW.1 to the conventional S / C ring 1 without separately providing it to the motor drive device, by setting the S / C ring 1 to the L position, the power supply can be changed. The consumption of E and e1 can be completely cut, which is effective for effective use of space and energy saving. In the second constant voltage circuit, the power source E
Is a small current supply switch SW.1 and a resistor connected in series.
It is connected in parallel with R1 and the diodes D1 to D5. Therefore,
Since the switch SW.1 is provided so that the voltage from the power supply E is directly supplied to the motor and directly to the first constant voltage circuit A1 via the transistor TR1, the energy of the power supply E is provided. There is an advantage that can be used effectively. Since the switch SW.1 is not directly connected between the power source E and the motor control circuit and the first constant voltage circuit A1, a voltage drop due to the contact resistance of the switch due to a large current does not occur, and the camera Even if switch SW.1 is turned off during operation, it does not malfunction.

As described above, according to the present invention, when the photographing operation is set, that is, when the photographing mode is set, the constant voltage circuit for the latch release circuit is activated to supply power to the latch release circuit. Since it is performed, it is possible to stabilize the photometric circuit before the photometric operation, and when power is supplied to the photometric circuit (when the half-push switch is ON).
Therefore, an accurate photometric output can always be obtained. Therefore, the photographing operation can be performed immediately after the half-push switch is turned on, so that the photographing apparatus is less likely to miss the shutter chance.

Further, according to the present invention, power is supplied to the latch release circuit only when the shooting mode is set, and power is supplied to the photometric circuit only when the half-push switch is operated. Power consumption can be eliminated. Therefore, according to the present invention, the minimum necessary current can be appropriately made to flow from the power supply, and the energy of the entire image capturing apparatus can be saved.

[Brief description of drawings]

1 to 6 show a preferred embodiment of the present invention.
FIG. 1A is a front view of the motor drive device,
FIG. 1B is a plan view of FIG. 1A, FIGS. 2 and 3 are vertical cross-sectional views of the grip portion of FIG. 1A, and FIGS. FIG. 6 is a sectional view taken along the line AA of FIGS. 2 and 3, and FIG. 6 is a circuit diagram of the motor drive device. (Description of symbols of main parts) 1 ... S / C ring (mode switching switch) 2 ... Release button A1 ... First constant voltage circuit E, SW.1, R1, D1 to D5 ... Second constant voltage Circuit E …… Motor drive power supply SW.1 …… Small current supply switch R1 …… Resistance D1 to D5 …… Diode A3 …… Release circuit a2 …… Exposure control circuit

Claims (2)

[Scope of utility model registration request] 1. A half-press switch that is energized when pressed to a first stage, and a release switch that is energized when pressed to a second stage deeper than the first stage to activate a shutter of the camera. A release button provided, a lock mode for preventing the operation of the release button, and a shooting mode for permitting the operation of the release button to be selected by an external operation, a mode switching means, a photometric circuit for measuring the subject brightness, In order to operate the photometric circuit, a constant-voltage circuit for photometric circuit that supplies power to the photometric circuit, a latch release circuit for stably operating the photometric circuit, and a latch release circuit that supplies power to the latch release circuit. Constant voltage circuit, and when the lock mode is selected, the latch release circuit constant voltage circuit and the photometric circuit constant voltage circuit perform the latch release operation. The power supply to the circuit and the photometry circuit is prohibited, and when the photographing mode is selected, the power supply from the latch release circuit constant voltage circuit to the latch release circuit is allowed, and further, according to the energization of the half-press switch. And a control means for permitting power supply from the constant voltage circuit for the photometric circuit to the photometric circuit. 2. The photographing device includes a camera body and a motor drive device, the camera body includes the photometric circuit and the latch release circuit, and the motor drive device includes the release button and the both buttons. The photographing apparatus according to claim 1, further comprising a constant voltage circuit, the mode switching means, and the control means.