JPH08115795A - Electronic flashing apparatus - Google Patents

Abstract

PURPOSE: To provide an electronic flashing apparatus for cameras and which can measure the actual temperature of an oscillation transistor, etc., and prevent overheating. CONSTITUTION: A temperature fuse 100 is press-held by a heat radiating plate 31a of an oscillation transistor 31 of a voltage boosting circuit and a holding member 200 whose one end is curved in S-shape as to closely attached to a thermally conductive part of the temperature fuse 100 and joined with the heat radiating plate, whose the other end has an extended part 200b, and whose whole body is formed into a clip-like shape out of a spring member. The temperature fuse 100 is connected between the oscillation transistor and an electric power supply, so that the temperature fuse is cut due to the actual temperature when the temperature of the oscillation transistor rises and oscillation is stopped and charging of a capacitor for a flash is stopped.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic flash device for a camera, and more particularly to a safety device against overheating of a flash booster circuit.

[0002]

2. Description of the Related Art Conventionally, a flash device (electronic flash device) of a camera has a booster circuit for boosting a power source (battery or the like) to charge a main capacitor. This main capacitor is charged with high voltage and discharged into a flash discharge tube to emit light. As a constituent element of the booster circuit, there are a switching element such as an oscillating transistor and a boosting transformer.
It is converted into C, boosted by a transformer and further rectified to charge the main capacitor. At this time, conversion energy loss occurs in the oscillation transistor and the transformer, which appears as heat generation of the element.

[0003]

However, in the above-mentioned conventional example, in the case of a failure mode in which the oscillation transistor or the like abnormally generates heat due to defective parts or the like, the ambient temperature is measured by a temperature sensor or the like to set the temperature. If it exceeds the limit, measures such as stopping the charging operation were taken.

In this case, since the temperature detecting portion for measuring the temperature and the oscillation transistor of the actual heating element are arranged apart from each other, the temperature of the heating element cannot be directly measured. There is a problem that it is difficult to determine the set temperature to stop. Therefore, an object of the present invention as set forth in claim 1 is to provide an electronic flash device capable of measuring and coping with an actual temperature of a constituent element such as an oscillation transistor of a booster circuit.

It is an object of the present invention as set forth in claims 2 and 7 to provide an electronic flash device which enhances the safety of the device by accurately determining the set temperature at which the charging operation is stopped.

An object of the present invention as set forth in claims 5 and 6 is to provide an electronic flash device capable of directly and accurately measuring the actual temperature of the constituent elements of the booster circuit and having a space-saving element arrangement configuration. Especially.

The object of the present invention as set forth in claims 8 to 13 is to allow the actual temperature of the constituent elements such as the oscillation transistor of the booster circuit to be accurately detected and to allow the user to recognize the situation by a warning display when abnormal heat is generated. It is to provide an electronic flash device capable of

[0008]

To achieve the above object, the present invention as set forth in claim 1, comprises a flash discharge tube, a main capacitor for supplying light emission energy to the flash discharge tube,
In an electronic flash device of a camera having a boosting means for performing a boosting operation to charge the main capacitor, a temperature detecting means for detecting a heat generation temperature of a constituent element of the boosting means,
The gist of the present invention is to provide a holding means for closely contacting the temperature detecting means with the constituent element of the boosting means.

Further, the present invention according to claim 2 is characterized in that the temperature detecting means is a thermal fuse.

Further, the present invention as set forth in claim 3 is characterized in that the temperature detecting means is a temperature sensor.

Further, the present invention according to claim 4 is characterized in that the constituent element of the boosting means is an oscillation transistor.

Further, in the present invention as set forth in claim 5, the holding means is engaged with the heat radiating plate for holding and pressing the heat conducting portion of the temperature detecting means so as to contact the heat radiating plate of the constituent element of the boosting means. The gist of the invention is that it is a spring member having a bent portion at one end and an extension portion at the other end.

Further, the present invention as set forth in claim 6 is characterized in that the springy member of the holding means has a clip shape.

Furthermore, the present invention as set forth in claim 7 is characterized in that the temperature fuse is blown when the temperature rises above the set temperature of the temperature detecting means, and the boosting means stops oscillation.

Further, the present invention according to claim 8 comprises a flash discharge tube, a main capacitor for supplying light emission energy to the flash discharge tube, and boosting means for performing a boosting operation to charge the main capacitor. In the electronic flash device of the camera which has the temperature detecting means for detecting the heat generation temperature of the constituent element of the boosting means, the holding means for bringing the temperature detecting means into close contact with the constituent element of the boosting means, and the temperature detecting means are set. Notification means for notifying the microcomputer that the temperature has been reached,
It is a gist to provide a warning means for displaying a warning based on the notification of the notification means.

Furthermore, the present invention according to claim 9 is characterized in that the temperature detecting means is a thermal fuse.

Furthermore, the present invention as set forth in claim 10 is characterized in that the notifying means is a one-shot pulse generating circuit connected in parallel to the temperature fuse.

Furthermore, the present invention as set forth in claim 11 is characterized in that the constituent element of the boosting means is an oscillation transistor.

Further, in the present invention as set forth in claim 12, the holding means is engaged with the heat radiating plate for holding and pressing the heat conducting portion of the temperature detecting means so as to contact the heat radiating plate of the constituent element of the boosting means. The gist of the invention is that it is a spring member having a bent portion at one end and an extension portion at the other end.

Furthermore, the present invention as set forth in claim 13 is characterized in that the springy member of the holding means has a clip shape.

[0021]

According to the present invention as set forth in claim 1, the temperature detecting means for detecting the temperature of the constituent element of the boosting means is arranged so as to be brought into close contact with the constituent element of the boosting means by the holding means. The actual temperature of the component can be measured.

According to the present invention as set forth in claims 2 and 7, when the temperature exceeds the set temperature of the temperature detecting means, the temperature fuse is blown and the boosting means stops the oscillation. Therefore, the oscillation of the boosting means is stopped and the main capacitor is charged. The set temperature for stopping can be accurately determined.

According to the present invention as set forth in claims 5 and 6, the whole is formed in a clip shape with a spring member, one end is a bent portion which engages with the heat dissipation plate of the constituent element of the boosting means, and the other end is By the holding means which is the extending portion, the heat conducting portion of the temperature detecting means is held and pressed so as to be in close contact with the heat dissipation plate of the constituent element of the boosting means. The actual temperature of the constituent elements of the means can be measured directly and accurately.

According to the present invention as set forth in claims 8 to 13, the temperature detecting means is brought into close contact with the constituent element of the boosting means by the holding means, and when the temperature of the constituent element reaches the set temperature by the temperature detecting means, the notifying means. The one-shot pulse generator circuit generates a pulse to notify the microcomputer, and the warning means displays a warning, so the user is warned that the temperature fuse has blown and the temperature fuse has blown and the main capacitor charging operation has stopped. can do.

[0025]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. 1 is a block diagram of an electronic flash device according to a first embodiment of the present invention. FIG. 2 is a view showing the structure of a holding member for mounting the temperature detecting means shown in FIG. FIG. 3 is a circuit block diagram of the electronic flash device shown in FIG.

In the electronic flash device of this embodiment, the battery 1 for power supply, its switch 2, and the DC voltage of the battery 1 are supplied to the microcomputer 17
Based on the OSC signal of
Boosting means 3 for converting into C voltage, temperature detecting means 1000 for mounting the oscillation transistor of the boosting means 3 to detect a heat generation temperature with a temperature fuse, diode 4 for rectifying the AC voltage of the boosting means 3, and rectified voltage value. It comprises a voltage detection circuit 5 for detecting the voltage, a main capacitor 6 for charging the flash voltage, and a flash discharge tube 14 for emitting light at the charging voltage of the main capacitor 6 by the TRG signal of the microcomputer 17.

FIG. 2 is a view showing a mounting structure of a holding member 200 which is a holding means for fixing the temperature fuse 100 of the temperature detecting means 1000, and FIG. 2 (a) is a front view.
(B) is a rear view and (c) is a side view.

The holding member (or clip member) shown in FIG.
Reference numeral 200 denotes a springy material having a good heat dissipation property such as metal, and has a bent portion 2 at one end that engages with the heat dissipation plate 31a of the oscillation transistor 31.
00a is formed at the other end of the extended portion 200b, and the heat conducting portion of the cylindrical thermal fuse 100 and the heat radiating plate 31a of the oscillation transistor 31 are engaged with each other. The bent portion 200a is bent into an S shape to facilitate the attachment / detachment, and the thermal fuse 100 can be replaced.

FIG. 3 is a circuit block diagram of a camera using the electronic flash device of this embodiment.

A battery 1, a switch 2 connected to the battery 1 for controlling power supply to a load, and a boosting means (a boosting circuit)
3 is P whose emitter is connected to the battery 1 via the switch 2.
NP type oscillation transistor 31 and oscillation transistor 31
Temperature detection circuit 10 including a temperature fuse 100, which is attached to the terminal and connects one end of the terminal to the emitter and the other end to the switch 2.
00, the heat generation of the oscillation transistor 31 is directly detected and the temperature fuse 100 is blown when the temperature exceeds a preset temperature,
The power supply to the oscillator circuit is cut off.

Further, the NPN transistor 32 (the oscillation control signal OSC is applied to the base of the transistor 32 via the diode 35) for controlling the oscillation start of the oscillation transistor 31, and the primary winding 36a is connected to the oscillation transistor 3.
The feedback winding 36b is composed of the transistor 32 and the resistor 7, and the secondary winding 36c is composed of the oscillating boosting transformer 36 connected to the rectifying diode 4 at the collector of 1.

The diode 4 is a high-voltage rectifying diode, which rectifies the AC output of the booster circuit 3 again and outputs a charging voltage.

In the voltage detection circuit 5, the charging voltage applied to the main capacitor 6 is proportionally divided by the resistors 51 and 52 and input to the microcomputer 17 as a SEN signal for voltage detection. The microcomputer 17 performs A / D conversion to check the voltage. I do. The capacitors 51 and 53 are capacitors for stability detection.

The discharge circuit using the flash discharge tube 14 includes a resistor 7 connected to the output of the main capacitor 6, a trigger capacitor 8, a light emitting thyristor 9 whose gate is triggered by a trigger TRG signal from the microcomputer 17, a trigger transformer 13, and a capacitor 26. And a voltage doubler circuit composed of a resistor 27 and a diode 28, and the charging voltage of the main capacitor 6 is charged to the trigger capacitors 8 and 26 via the resistor 7,
The thyristor 9 is turned on by the TRG signal from the microcomputer 17.
Then, the trigger capacitors 8 and 26 are discharged N to generate a high-voltage pulse on the secondary side of the trigger transformer 13 to operate the flash discharge tube 14 to emit light.

In addition, the operation circuits of a normal camera are listed below. A constant voltage circuit 15 for outputting a constant voltage Vcc, a switch control circuit 16 for controlling the camera, a one-chip microcomputer (hereinafter abbreviated as a microcomputer) 17, a microcomputer circuit 171 including a CPU, a ROM and a RAM, IO control circuit 172, A
It has a / D converter 173, a multiplexer 174, a timer circuit, and the like.

AFC signal is sent from the microcomputer 17 for AFD
An AF circuit 18 for returning a signal, an AE circuit 19 for sending an AEC signal from the microcomputer 17 and for returning an AED signal, a display circuit 20 for displaying various information, a shutter circuit 21 including a cycloswitch, and an aperture control circuit 22 for aperture. Further, a light emission stop circuit 23 for controlling the thyristor 231 to stop light emission by a TRG2 signal from the microcomputer 17, a remote control receiving circuit 24 and the like are provided.

The remote control transmission circuit block 25 includes a remote control transmission LED 251, a transmission circuit 252, and a power supply battery 2.
53, a release signal transmission switch 254, and a remote control mode selection switch 255 for two types of signals. Each mode in this case is, for example, the switch 254 in mode 1.
Is a mode in which the shutter is immediately released when is turned on, and mode 2 is a mode in which the switch is released arbitrarily (for example, 2 seconds later) after the switch 254 is turned on. The light emission signal transmitted from the remote control transmission block 25 is received by the remote control reception circuit 24, the signal is decoded, and transmitted to the microcomputer 17 as T1 and T2 signals.

The film sensitivity detection circuit 400 is the microcomputer 1
7 to send the film speed information (ISO).

4 to 9 are flowcharts of the operation of the camera shown in FIG. Next, the operation will be described with reference to the drawings.

Referring to FIGS. 4 and 5, first, when the power switch 2 is turned on, the battery 1 is connected to the booster circuit 3, the constant voltage circuit 15 is activated and a constant voltage is supplied to each part, and the microcomputer 17 internally operates. The CPU 171 is reset.

Initialization is performed, flags FAL (for flash), RCHG (recharge), remSW (remote) are cleared, and memory contents are reset (S1). The switch circuit 16 detects a switch for controlling the camera (shutter, aperture, flash mode switch, remote controller, film sensitivity switch, zoom, release switch, etc.),
It is transmitted to the microcomputer 17. Film sensitivity detection circuit 400
Automatically reads the film sensitivity such as DX code (S2), and if the remote control switch flag remSW is "1" while the remote control is in use, proceed to S4. If not, proceed to S4.
Proceed to 3 (S2a).

It is determined whether SW1 is ON. If it is OFF, the process returns to S2 (S3), and if it is ON, the voltage of the power supply battery 1 is detected by the microcomputer 17 (S4). When the battery voltage is equal to or lower than the minimum operating voltage of the camera, it is determined as NG and the process returns to S2 and is OK if it is large (S5).

An AFC signal is sent from the microcomputer 17 to the AF circuit 18, an AFD signal is sent back from the AF circuit, and focusing is performed by AF (S6). Microcomputer 17 to A
Send the AEC signal to the E circuit 19, and the AE circuit 19 sends the AE signal.
The D signal is returned and an appropriate exposure is calculated to determine the shutter speed and aperture (S7). The AF circuit 19 determines whether the subject brightness is low, and if a flash is required, the flag FA
Set L = 1 and proceed to S9. If not, set FAL = 0 and proceed to S10a (S8). A flash charging sequence is performed in the flash mode (S9).

The microcomputer 17 determines the completion of charging and displays the completion of charging on the display circuit 20. If not completed, S2
Return to (S10). If charging is completed, flag remSW =
It is determined whether it is 1 (S10a). When remSW = 1,
Further, it is determined whether the remote control timer flag remT = 0. r
When emT = 1, the process waits until the timer measurement is completed, and the process proceeds to S12 (10b). It is determined whether the release SW2 is ON (S1
1). After that, the process moves to FIG.

Focusing is performed by driving the lens (S12).
The shutter circuit 21 and the diaphragm circuit 22 perform shutter, diaphragm control, and light emission control according to a signal from the microcomputer 17 (S
13). Details will be described later. Then, the lens (not shown) is driven to return to the reset position (S14). Further, the film winding operation is performed (S15). The flash flag FAL is determined. If FAL = 1, the process returns to S17, and if not, the process returns to S2 (S16). A charging sequence is performed in the flash mode (S17).

Next, the switch detection operation of the process of S2 will be described in more detail. FIG. 6 is a subroutine for remote control switch detection in S2 of FIG. From FIG. 6, the state of the remote control switch is detected (S201). It is determined whether the mode is the remote control mode, and if not used, the process proceeds to S208 (S208).
202). If the remote control is being used, the flag remSW = 1 is set (S203). Then, the remote control reception circuit 24 receives the light emission signal of the remote control transmission circuit block 25 and determines whether or not the signal can be decoded (S204). If the determination result mode 1 is S206, the mode 2 is S207
Proceed to (S205).

Next, the remote control mode flag remM =
0 and the timer flag remT = 0 (S206). r
When emm = 1, the timer measurement is started, and when the measurement is completed, remT = 0 (S207). And S2a
Proceed to. If the remote control mode is inoperative, remSW = 0 is set and the process proceeds to S2a (S208).

Next, details of the charging operation in the flash mode shown in the processing in S9 of FIG. 4 will be described. 7 and 8 show the flash mode subroutine in S9 of FIG. From FIG. 7, FAL = 1 indicating that the flash is used is set (S901).

The state of the remote control switch is determined. If remSW = 1 when using the remote control, go to S903, not use r
When emSW = 0, the process proceeds to S911 (S902). Determine whether the remote control mode is mode 1 or mode 2
When (remM = 0), go to S904 Mode 2 (remM
When = 1), the process proceeds to S911 (S903). Microcomputer 1
7 checks the charging voltage from the voltage detection circuit 5 to check the oscillation of the booster circuit 3 (S904).

Then, it is determined whether or not the checked charging voltage is a voltage capable of emitting light from the flash discharge tube 14 and is at a level sufficient for photographing, and when light emission is not possible, the process proceeds to S909 (S905).

When light emission is possible, the OSC signal is changed from "HL" to "LL" to stop the operation of the booster circuit 3 (S906).

If the recharge flag RCHG (representing charging to the lowest light emission level) is "0", it means that the main capacitor 6 is in the charged state, and the emission energy is 1/2 (CV ² ) from the charge voltage value and the capacitor capacitance value of the main capacitor 6. The calculated shutter speed and aperture value are calculated in consideration of the film sensitivity read value and the proper exposure with this energy amount (S907).

Next, the recharge flag RCHG is set to "0" and the process proceeds to S10 (S908). When it is below the minimum light emission level in S905, the recharge flag RCHG = 1 is set (S9
09).

The OSC signal is set to "L" to start the boosting operation.
The main capacitor 6 is charged by switching from "L" to "HL", and the process proceeds to S905 (S910).

RemSW = 0 in S902, r in S903
When emm = 1, the voltage dividing resistors 52 and 53 of the voltage detection circuit 5
The divided voltage (SEN signal) by the A / D converter 1
The value is converted into a digital value by the 73 multiplexer 174, and it is determined whether or not the voltage is the full charge voltage at which the flash discharge tube 14 can emit light (S911). If the charge is complete, the OSC signal is changed from "HL" to "LL" to stop the oscillation of the oscillation transistor 31 (912).

Next, the recharge flag RCHG = 0 is set to S.
It progresses to 10 (S913). When it is below the charge completion level in S911, the recharge flag RCHG = 1 is set (S91).
5). The OSC signal changes from "LL" to "H" for boosting operation.
The main capacitor 6 is charged by changing to "L" (S91).
6).

Next, details of the shutter, aperture control, and light emission control in the process of S13 of FIG. 5 will be described. FIG. 9 is an operation flowchart of shutter and aperture control. According to FIG. 9, S7
Then, the control operation of the shutter circuit 21 and the aperture circuit 22 is started in order to obtain the shutter and aperture value determined by the photometric data of (S1301).

The flag FAL is determined. If FAL = 0, the process proceeds to S1306 (S1302). When FAL = 1, the trigger signal TRG is output (S1303).

When the TRG signal turns on the thyristor 9 via the resistor 12 in a state where a high voltage is applied to the flash discharge tube 14 by charging the main capacitor 6, the capacitors 8 and 26 are discharged.
When the thyristor 9 is turned on, the voltage of the sum of the main capacitor 6 and the capacitor 26 is applied to the flash discharge tube 14, and a high voltage pulse is generated on the secondary side of the transformer 13 to emit light (13).
04). Then, light is emitted by an amount of light emission corresponding to the charge level of the main capacitor 6, and the light emission is stopped when the discharge is completed (S1305). After the shutter and diaphragm control is completed, S14
Proceed to (S1306).

In the above, the A / D of the microcomputer 17
The converter 173 may be replaced by two comparators, one for charging completion and one for minimum emission voltage.

Further, instead of the thermal fuse 100, it is also possible to use a thermal switching element or the like which can obtain other similar operations.

Further, a temperature sensor such as a thermistor having a sharp resistance change characteristic near the set temperature is selected, and similarly, it is closely attached to the heat sink of the transistor to detect the actual temperature, and the booster circuit 3 is turned off. It is also possible to configure.

As described above, the flash circuit of the camera operates according to the program of the microcomputer 17, but in the present embodiment, the oscillation operation is unstable due to a defect, disconnection, short circuit or the like of the constituent elements in the booster circuit 3. When the oscillation transistor 31 and the like generate heat, the temperature fuse 100 of the temperature detecting means 1000 is connected between the power switch 2 and the emitter of the oscillation transistor 31, and the temperature fuse 100 is directly connected to the heat sink 31a of the oscillation transistor 31. Since it is mounted, as soon as the actual heating temperature of the oscillation transistor 31 reaches the set temperature determined by the thermal fuse 100, it is possible to avoid an unexpected situation such as overheating due to the thermal fuse being cut off, the power supply being cut off, and the oscillation being stopped. .

Next, a second embodiment of the present invention will be described. FIG. 10 is a block diagram of the temperature detecting means according to the second embodiment of the present invention. FIG. 11 is a flowchart of the operation of the second embodiment shown in FIG.

As shown in FIG. 10, the circuit for notifying the microcomputer 17 of the disconnection of the thermal fuse 100 of the second embodiment is as follows.
Similar to the first embodiment, the heat dissipation plate 31 of the oscillation transistor 31
The one-shot pulse generation circuit is formed by serially connecting a capacitor 101, which is closely connected to a, and is connected to a temperature fuse 100 in parallel, and a resistor 102. The connection point of the CR series circuit is connected to the microcomputer 17 by a signal line HC. .

In this CR series circuit, the current is cut off by the capacitor 101 in the normal state, and when the temperature fuse 100 is cut off, the CR series circuit is discharged through the resistor 102 to generate a one-shot pulse.

The operation will be described with reference to FIG. First, abnormal oscillation occurs and the temperature of the oscillation transistor 31 rises (S101). Then, the temperature fuse 100 is cut off, the power supply to the booster circuit 3 is cut off, and the oscillation is stopped (S
102). Then, a one-shot pulse is generated from the circuit of the capacitor 101 and the resistor 102 (S103).

The microcomputer 17 detects the one-shot pulse and sets the OSC signal to "LL" to stop the oscillation (S
104). Further, the microcomputer 17 sends a DISP signal (display command) to the display circuit 20 so that the temperature fuse 100
Is displayed to the user as a warning (S105).

The thermal fuse 10 is also used in this embodiment.
0 can be replaced by another temperature switch element or a temperature sensor circuit.

As described above, in the present embodiment, the disconnection of the thermal fuse is surely detected by the one-shot pulse and the warning is displayed, so that the user can deal with it without anxiety.

[0071]

As described above, in the electronic flash device of the present invention as defined in claim 1, the temperature detecting means for detecting the heat generation temperature of the constituent element of the boosting means and the temperature detecting means for the constituent element of the boosting means. Since the holding means for closely contacting is provided, the actual temperature of the constituent element of the boosting means can be directly measured to prevent an unexpected situation due to overheating or the like.

Further, in the electronic flash device of the present invention as set forth in claims 2 and 7, when the temperature reaches the set temperature of the temperature detecting means, the temperature fuse is blown to stop the oscillation of the boosting means. The temperature fuse can be set accurately and the safety of the device is enhanced by cutting off the current by cutting the temperature fuse. Further, in the electronic flash device of the present invention as set forth in claims 5 and 6, the whole is formed in a clip shape with a spring member, one end is a bent portion which engages with a heat dissipation plate of a constituent element of the booster and the other end is Since the holding means, which is the extending portion, is configured so that the heat conducting portion of the temperature detecting means is brought into close contact with and held by the heat radiating plate of the constituent element of the boosting means, the temperature detecting means is surely attached to the heat radiating plate of the constituent element of the boosting means. In addition to being able to hold them in close contact, usually the holding means itself also has the effect of a heat sink, and since the temperature fuse does not need to be integrated with the constituent elements and arranged on the substrate, a space-saving element arrangement structure can also be realized. .

Further, in the electronic flash device of the present invention as set forth in claims 8 to 13, the temperature detecting means is held in close contact with the constituent element of the boosting means by the holding means, and the temperature of the constituent element reaches the set temperature of the temperature detecting means. When the notification means reaches the microcomputer with a one-shot pulse when the temperature reaches, and the warning means displays the warning, the temperature at which the oscillation operation is stopped can be set accurately, and the temperature fuse is blown when the temperature reaches the set temperature. The user can recognize from the warning display that the operation is stopped and the charging operation of the main capacitor is stopped, and the user can deal with it with peace of mind.

[Brief description of drawings]

FIG. 1 is a configuration diagram of an electronic flash device according to a first embodiment of the present invention.

FIG. 2 is a diagram showing a structure of a holding member on which the temperature detecting means shown in FIG. 1 is mounted.

FIG. 3 is a circuit block diagram of the first embodiment shown in FIG.

FIG. 4 is a flowchart of the operation of the first embodiment shown in FIG.

5 is a flowchart of the operation of the first embodiment shown in FIG.

FIG. 6 is a subroutine of a switch detection process shown in FIG.

FIG. 7 is a subroutine of a flash mode process shown in FIG.

8 is a subroutine of the flash mode process shown in FIG.

9 is a subroutine of shutter / aperture control and light emission control processing shown in FIG.

FIG. 10 is a circuit diagram of an electronic flash device according to a second embodiment of the present invention.

11 is a flowchart of the operation of the second embodiment shown in FIG.

[Explanation of symbols]

 1 Battery 2 Power Switch 3 Booster Circuit 4 High Voltage Rectifier Diode 5 Voltage Detection Circuit 6 Main Capacitor 14 Flash Discharge Tube 31 Oscillation Transistor 100 Thermal Fuse 200 Holding Member 1000 Temperature Detection Circuit

Claims (13)

[Claims] 1. An electronic flash device for a camera, comprising: a flash discharge tube, a main capacitor for supplying emission energy to the flash discharge tube, and boosting means for performing a boosting operation to charge the main capacitor. An electronic flash device, comprising: a temperature detecting means for detecting a heat generation temperature of a constituent element of the means; and a holding means for bringing the temperature detecting means into close contact with the constituent element of the boosting means. 2. The electronic flash device according to claim 1, wherein the temperature detecting means is a thermal fuse. 3. The electronic flash device according to claim 1, wherein the temperature detecting means is a temperature sensor. 4. The electronic flash device according to claim 1, wherein the constituent element of the boosting means is an oscillation transistor. 5. The holding means has a bent portion at one end that engages with the heat radiating plate that holds and presses the heat conducting portion of the temperature detecting means so as to contact the heat radiating plate of the constituent element of the boosting means, and at the other end. The electronic flash device according to claim 1, wherein the electronic flash device is a spring member having an extending portion. 6. The electronic flash device according to claim 1, wherein the springy member of the holding means has a clip shape. 7. The electronic flash device according to claim 1, wherein the temperature fuse is blown when the temperature rises above the set temperature of the temperature detecting means, and the boosting means stops oscillation. 8. An electronic flash device for a camera, comprising: a flash discharge tube, a main capacitor for supplying light emission energy to the flash discharge tube, and boosting means for performing a boosting operation to charge the main capacitor. Temperature detecting means for detecting the heat generation temperature of the constituent elements of the means, holding means for bringing the temperature detecting means into close contact with the constituent elements of the boosting means, and notifying the microcomputer that the temperature set by the temperature detecting means has been reached. An electronic flash device comprising: a notification means and a warning means for displaying a warning based on the notification of the notification means. 9. The electronic flash device according to claim 8, wherein the temperature detecting means is a thermal fuse. 10. The electronic flash device according to claim 8, wherein the notification means is a one-shot pulse generation circuit connected in parallel with the temperature fuse. 11. An electronic flash device according to claim 8, wherein the constituent element of the boosting means is an oscillation transistor. 12. The holding means has a bent portion at one end that engages with the heat radiating plate that holds and presses the heat conducting portion of the temperature detecting means so as to contact the heat radiating plate of the constituent element of the boosting means, and at the other end. 9. The electronic flash device according to claim 8, wherein the electronic flash device is a spring member having an extending portion. 13. The electronic flash device according to claim 8, wherein the springy member of the holding means has a clip shape.