JPS60177327A - Power supply device of camera - Google Patents

Abstract

PURPOSE:To use a penlight battery, a smaller battery, and a lithium battery as a common power source by providing connector terminals separately and changing ways of using according to an in-use battery. CONSTITUTION:When the penlight battery and smaller battery are used, 3V is applied between connector terminals 14 and 15 and an exposure control circuit 18, AF control circuit 19, and flash circuit 20 are all allowed to operate at 3V. When the lithium battery is used, on the other hand, 6V is applied between the connector terminals 14 and 16 and 3V obtained by regulating 6V is applied between connector terminals 15 and 16'.

Description

[Detailed description of the invention]

FIELD OF INDUSTRIAL APPLICATION The present invention relates to a power supply device for supplying power to electronic circuits such as a camera's flash circuit, exposure convenience circuit, and control circuit of a camera. In particular, the present invention relates to such a power supply device for a small camera of the Cub Hill type. 1 Disappointing Technology] Currently, AA or AAA manganese batteries, mercury batteries, silver batteries, lithium batteries, etc. are used as the electric cell pond for the No. J Mela, but flashco circuits and automatic film winding are Cameras with rewind circuits use large currents, so AA or AAA batteries or lithium batteries with a current capacity of iQ are used. However, since AA or AAA batteries and lithium batteries have different sizes and shapes, the reality is that only one type of battery that is compatible with the battery case can be used. Although AAA batteries are small, they are sometimes difficult to obtain because they are in small quantities on the market.On the other hand, AA batteries are in abundant supply, but due to the restriction of large serrations, two batteries must be connected in series. It is often used at 3V, making it unsuitable for rapid charging of flashlights, and has drawbacks such as slow film winding and rewinding. Also, lithium batteries have low internal resistance, so
It is advantageous for quick charging of flash, but 2.
It can only generate a voltage of about 8V, making it unsuitable for cameras driven by 3V.On the other hand, it is disadvantageous in terms of cost because the price per unit is high, although two units are used. In this way, AA batteries, AAA batteries, and lithium batteries each have their advantages and disadvantages, and they differ depending on the usage [1].

[I have no choice but to give up. In order to be able to use three types of batteries, you can make the battery box replaceable, and remove the battery box that matches the battery you want to use from the camera so that it can be used (=l(), but the problem in this case is For the reasons mentioned above, AA batteries and AAA batteries provide a 3V power supply, while lithium batteries provide a 6V power supply. If the AF control circuit is designed for 3V,
When using AA and AAA batteries, the appropriate 3V for these circuits
However, when using a lithium battery, 6V is supplied, which may exceed the absolute adult rating and cause the circuit to be destroyed. Some of them are 6V (set B by Mr. 1')
If 3V is supplied, the performance cannot be guaranteed. However, it is unnecessary to replace and use AA batteries, AAA batteries, and lithium batteries in the circuit including the flash circuit, exposure control circuit, and control circuit. As described above, the present invention was made in view of the problems that occur when using 11-3 batteries, AAA batteries, and lithium batteries as power sources in common, and the purpose of the present invention is to provide power to the flash circuit. Separately connect the connector terminal that supplies power to the exposure control circuit and the A[control circuit. When using a lithium battery, connect 6■ to the flashco circuit and 6
3■ made by legigorating V is the exposure control circuit and A
By supplying it to the F control circuit, it is possible to use AA batteries, AAA batteries, and lithium batteries as a common power source for the same camera, and when using lithium batteries, it is possible to quickly charge the flash. It is in. [Description of Embodiments] Hereinafter, a power supply device for a camera according to the present invention will be described based on the drawings. FIG. 1 shows a block diagram of the electrical system of a camera to which the present invention is applied. Reference numerals 11 are electronic circuits within the camera or attached to the camera that receive power supply from a power supply block 12; an exposure control circuit 18; an AF (focus on all) control circuit 19; and a flash circuit 20. The flash circuit 20 includes a limiter circuit 23, which will be described later.The power supply block 12 includes a power supply circuit 13.14, 15, 16, and 16' supply power from the power supply block 12 to the electronic circuit 10 of the camera body. It is a connector terminal for supplying terminals, and terminals 14゜16
is for the higher voltage and terminal 15.16' is for the lower voltage. These connector terminals 14.15.16,16
' is paired with a connector terminal installed on the camera body, and is connected by attaching the power supply block 12 to the camera body. Barrier-type cameras or small capsule-type cameras have a barrier that can be slid laterally on the front of the camera to prevent the lens and other optical components on the front of the camera from being scratched when carried. 17 is a switch that opens and closes in conjunction with this barrier. This switch 17 is turned on by opening this barrier, and power is supplied to the exposure control circuit 18 and the ΔF control circuit 19. The open barrier state means that the camera is not used, so that the barrier switch 17 is opened. In the power supply block 12, the first power supply voltage of the power supply circuit 13 is connected to the connector terminal 14, the second power supply voltage that outputs a specified voltage is connected to the connector terminal 15, and the power supply voltage is connected to the connector terminal 16. The first GND of the circuit 13 is connected, and the connector terminal 16
' is connected to the second GND. FIG. 2 shows a configuration in which AA batteries or AAA batteries are used as the power source in the power supply circuit 13. Connector terminals 14 and 15 are connected to the anode of an AA battery or AAA battery, and connector terminals 1G and IG' are connected to the cathode of the battery, and the flash circuit 20, exposure control circuit 18 and AF
All the control circuits 19 are supplied with 3■. FIG. 3 shows a configuration in which a lithium battery is used as the power source in the power supply circuit 13. 24 indicates a Kl 2 wood lithium battery, 25 is a temperature fuse, and 26 is a 3V regulator. Although a known voltage regulating circuit can be used as the regulator 26, it is sufficient for the present invention to eliminate the influence of the operation of the flash circuit 20. Lithium batteries may generate heat, so for safety, set temperature fuse 25. 6V of the lithium battery 24 is directly outputted between the connector terminal 14 and the connector terminal 16, but 3V of regulated 6V is outputted between the connector terminal 15 and the connector terminal 16'. The connector terminal 16 is connected to the cathode of the lithium battery, and the connector terminal 16' is connected to the GNr of the regulator 26.
). ] The reason why the connector terminal 16' is provided separately from the connector terminal 6 is because if these terminals are used in common, the battery will be consumed even when the power supply box 12 is removed from the camera. In this way, when using a lithium battery, the exposure control circuit 18 and the AF control circuit 19 are supplied with 3.
The flash circuit 20 is supplied with 6■. By supplying 6V to the flash circuit 20, it is possible to quickly charge the main sensor for Flashini L, but if you charge it to too high a voltage, the main sensor will be damaged! If the voltage exceeds 8, there is a risk of destroying the main unit. Therefore, it is necessary to set a voltage lower than the rated voltage of the main battery as a limit voltage, and to stop charging when the charging voltage reaches this limit voltage. To stop this charging, a limiter circuit 23 that stops charging at a predetermined voltage value may be provided in the flash circuit 20, as shown in FIG. FIG. 4 shows a specific circuit example of the regulator 26. In FIG. 4, the input terminal 37 of the regulator 26 is
It is connected to the child terminal of the lithium battery 24, the GND terminal 38 is connected to the connector terminal 16', and the output terminal 39 is connected to the connector terminal 15. Transistors Q7 and Q8 have a Darlington configuration, with both collectors connected to the input terminal 37, the -mitter of the transistor Q7 connected to the output terminal 39, and the base of the transistor Q8 connected to the =] of the transistor Q8 via a resistor R12. Connect to Rector. The base of transistor Q8 is also connected to the collector of transistor Q9. [-The emitter of transistor Q9 is connected to resistor R1
3 to the output terminal 39, and the Zener
Dia 1-Door 1] Connect to the card of 1. The anode of the Zener diode ZD1 is connected to GND. 15 is a potentiometer, one end of which is connected to the output terminal 39 via a resistor R14, and the other end is connected to GND via a resistor R16. Its sliding terminal connects to the base of transistor Q9. A smoothing capacitor C is connected between the output terminal 39 and the GND terminal 38.
5 is connected. Next, the circuit operation of this regicolator 26 will be explained, assuming that the output voltage increases by ΔVO due to some cause such as load fluctuation or external noise. Then, the base voltage of resistor R14 and [R1
However, since the emitter voltage of the l-transistor Q9 is kept constant by the action of the two-corner diode Zf)+, the collector current of the l-transistor Q9 is Paste/Δ■0 or increase. Here, it is the phase 17 conductor,
-ΔIc/Δ■be is defined as m. As a result, the base voltage of transistors 1 to Q8 decreases by approximately R12. The amount of change is approximately the amount of change in the mitter potential, and the voltage at the output terminal 39 decreases. This allows terminal 39 and terminal 38 to
The voltage between the two is stabilized. The above stabilizing operation is exactly the same even when the output voltage increases by ΔVo. FIG. 5 is a circuit diagram showing one embodiment of the limiter circuit 23. In FIG. In FIG. 5, the portion other than the power supply block 12 is a flash circuit 20. First, ``Fludge'' 2 circuits 2
The part of 0 excluding the limiter circuit belongs to the publicly known flash circuit, but to briefly describe its +14 circuit,
C1 is a power supply capacitor, the + terminal of which is connected to the positive power supply line, and the one terminal connected to the GND line. The oscillation capacitor C2, the oscillation 1 to transistors Qs and Qe, the resistor R6, the oscillation transformer 28, and the diode D+ constitute a tear pressure circuit, and boost the voltage of the battery to a high voltage (300 V or more). The positive power supply line connected to the connector terminal 14 of the R voltage circuit is connected to the GND line via the oscillation content C2 and resistor R6, and this GND line is
It is connected to the connector terminal 16 via the switch 27 (described later). Both J and the transmitter of the PNP type transistors Q5 and Q6 are connected to this positive power supply line, and both bases are connected to the 21 capacitor C2 and the resistor. It is connected to the connection point of R6, and both collectors are connected to one end of the primary winding of the oscillation transformer 28.The other end of the primary winding of the oscillation transformer 28 is connected to the GND line.Secondary winding of the oscillation transformer 28 One end of the rectifying diode D1 is connected to the anode of the rectifying diode D1, and the other end is connected to the connection point of the emission capacitor C2 and the resistor R6. It is a diode, and the rectified voltage is J, and the remaining capacitor C3 is charged. 30 is a neon lamp, and when the main capacitor C3 is charged more than a certain level, it lights up to indicate the completion of charging. R7 27 is a resistor that limits the current of the neon lamp 30. 27 is a pop-up switch that is linked to the pop-up of the flash discharge tube by a spring force or -E-taper. The charge remaining in the main capacitor C3 is discharged to ON+ to prevent accidental light emission at the time of release. When the switch 27 falls to the No side due to pop-up, the GN of the power supply circuit 13
L) and GND of the flash circuit 20 are connected, and voltage and charging of the main capacitor C3 are started. 3
2 is a so-called synchro switch, which is turned on by pressing the camera's release switch. 31 is a trigger transformer, synchro switch 3
2 turns on, the capacitor C4 discharges and excites the χ1 Helliger transformer 31, causing the flash discharge tube 33 to discharge and emit light. Next, the limiter circuit 23 will be explained. 29 is a detection circuit that detects the voltage rectified by the rectifier diode D1, that is, the voltage of the main capacitor C3, and its positive power supply line is the connection between the cathode of the rectifier diode D1 and the +9 terminal of the main capacitor C3. The GND line is common to the GND line of the flash circuit 20.The detection circuit 29 has the function of outputting a signal with a different level depending on whether the power supply voltage is above a predetermined threshold or not. 4. Details of the detection circuit 29 will be explained later with reference to FIG. 6.The output of the detection circuit 29 is connected to the base of the transistor Q1. ◆, and the collector of the transistor Q+ is connected to the base of the transistor Q2, and is also connected to the positive power supply line of the boost bypass circuit through the resistor [1].The collector of the transistor Q2 is
1 - Connected to the base of transistor Q3 and also connected to resistor 1
(Connected to the positive power supply line of the booster circuit through 3. The collector of transistor Q3 is connected to the piezoelectric voltage iI≦(line of the booster circuit through resistor 1
4 and resistor 1 (the connection point of 5) is connected to the base of helang resistor Q4. One transistor of transistor Q4 is connected to oscillation capacitor C2 and oscillation 1 to both transistors Qs and Qe.
The transmitter is connected to the positive voltage line of the 11J:jE circuit.The collector of transistor Q4 is connected to the connection point between resistor R6 and oscillation capacitor C2. The physical circuit array is shown (11 series circuit of resistor R17 and resistor 1 or 18 is connected in parallel with main capacitor C3, and if resistor 1<17, the connection point of resistor 1 or 18 is a Zener diode. The Zener diode ZD2 is connected to the cathode thereof, and the anode of the Zener diode ZD2 is connected to GND through a parallel circuit of a resistor R19 and a conductor C6.
The anode of D2 is connected to the base of transistor Q1 of FIG. Resistors R17 and R18 divide the charging voltage of the main capacitor C3, and the divided voltage is applied to the cathode of the Zener diode ZD2.
By appropriately selecting the Zener voltage of the diode ZD2 and the resistance value of the resistor R19, it is possible to tell the transistor Q1 whether the voltage of the main capacitor C3 has reached the charging stop voltage V2 (more safely, V+). It's too C. Next, the operation of the limiter circuit 23 is repeated d1. in general,
The time characteristics when the battery voltage is increased to a high voltage necessary for flash operation are as shown in FIG. In FIG. 7, numeral 34 indicates a characteristic curve when the main capacitor C3 is charged to a voltage 1 lower than the rated voltage V2 of the main capacitor 03 by boosting the voltage of the AA battery or AAA battery. 35 is a time characteristic curve when a lithium battery is used instead of an AA battery or an AAA battery to boost the voltage to 6V, and there is no limiter circuit. As can be seen from this figure, the time it takes for the charging voltage to reach ■1 is faster than in the case of AA batteries or AAA batteries. However, if this continues, the rated voltage V2 of the main capacitor C3 will be exceeded, and the main capacitor C3 will be destroyed. Therefore, it is necessary to limit the charging voltage to voltage <2> or less, and in this case, the characteristic curve becomes a constant voltage V2 due to the operation of the limiter circuit as shown in 36. The detection circuit 19 monitors whether or not the voltage of the main capacitor "C3" has reached the charging stop voltage V2 (more safely, V+), and if it has reached V2 (or V+), the "high" voltage is detected. If it is lower than V2 (or V+), a "low" voltage is output. First, when the charging characteristic is shown by the curve 34 in FIG. 6, the neon lamp 30 lights up at the charging voltage h': V3, indicating that charging is complete. In this case, the charging voltage is the charging stop voltage V2 (or V+
) does not reach, so the output of the detection circuit 19 is 1" low, and the transistor Q+ is off and the transistor Q2
is turned on, transistors Qa and Qa are turned off, the oscillation of the booster circuit does not stop, and the charging voltage of the main capacitor C3 is boosted to Vl. Next, when the charging characteristic is curve 35, similarly, when the charging voltage reaches v3, the neon lamp 30 lights up and the charging is about to be completed, but the time required to reach that point is extremely short, resulting in the so-called @fast charging. In this case, the main capacitor C3 is further charged beyond V3. The potential of main capacitor C3 is V2 (or Vls, however, below V2
will be explained using an example. ), the output of the detection circuit 19 becomes F high 1, transistor Ql is turned on, transistor Q2 is turned off, transistors Q3 and Qa are turned on, and the oscillation capacitor C2 is shorted, so the oscillation of the Te1 pressure circuit is stopped. It stops, and the charging voltage of the main capacitor 4j-03 becomes constant at V2. This is the charging characteristic curve 36 in Figure 7.
corresponds to In this way, by installing the limiter circuit 23 in the flash circuit 20, the same flash circuit can be safely used for both the 3V voltage of AA batteries and AAA batteries, and the 6V voltage of lithium batteries. [Effects of the Invention] As explained above, the present invention provides a connector terminal that supplies power to a circuit that is preferably operated at a higher voltage, such as a flash circuit, and a connector terminal that supplies power to a circuit that is preferably operated at a higher voltage, such as a flash circuit, and an ordinary low constant voltage. Connector terminals that supply power to circuits that operate in When using a lithium battery, 6V is supplied to the flash circuit, and regulated 3V of 6V is supplied to the exposure control circuit and ΔF control circuit. 4 batteries and a lithium battery can be used as a common power source for the same camera, and when using a lithium battery, it is possible to quickly charge the ``Fludge.'' 1. For this purpose,
When using a lithium battery, a constant voltage circuit can be realized with a simple circuit configuration by adding (=J).Furthermore, this constant voltage circuit does not consume any power when the power box is not attached to the camera. , long-term use of the battery will increase its capacity.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the relationship between a camera power supply device and various electronic circuits of the camera according to the present invention. Figure 2 shows a specific example of the configuration when using an AA battery or A4 battery as the power source, and Figure 3 shows a specific example of the configuration when using a lithium battery as the power source. . FIG. 4 does not show an example of a regulator circuit. 5 shows a specific circuit example of a flash circuit equipped with a limiter circuit. 1. FIG. 6 shows an example of the detection circuit of FIG. 5. Figure 7 shows
FIG. 3 is a characteristic diagram for explaining the function of a limiter circuit. 10... Power circuit inside the camera or belonging to the camera 12... Power supply box 13... Power supply circuit 14.
15.16...-'] Connector terminal 11... Barrier switch 18... Exposure control circuit 19... AF control circuit 20... Flash circuit 23... Limiter circuit 25... Temperature resistance: 1-Z 27... Pop-up switch 28... Oscillation transformer 29... Detection circuit 30... Neon lamp 31... Trigger transformer 32-1. Synchro switch 33... Flash discharge tube 1st figure 2nd figure 3rd figure 4th figure 6th figure 7th figure

Claims (1)

[Claims] (1) A first electronic circuit that operates at a first voltage consisting of;
a second electronic circuit, preferably operated at a higher voltage than the voltage of the box 1; a first connection for powering the electronic circuit of the box 1; a second connecting member that supplies power to the electronic circuit of the box 2; third and fourth connecting members that connect to the GND lines of the box 1 and the second electronic circuit; If the first battery suitable for supplying electricity 11 is stored, the box 1
A second connection member suitable for supplying the same voltage between the connection member and the connection member of the box 3 and between the second connection member and the fourth connection member and supplying a voltage higher than the voltage of the box 1. When storing batteries No. 2, the connection member of the box No. 2 and the box No. 4
The battery voltage is supplied between the connecting member of the box 1 and the connecting member of the box 33, and a power supply circuit that supplies a divided voltage of the battery voltage is provided between the connecting member of the box 1 and the connecting member of the box 33. power supply device for the camera. (2) The first connection member connects the first connection member to the first connection member via a barrier switch that opens and closes in response to a movable barrier on the front of the camera to protect the lens and other optical systems on the front of the camera when the camera is in use. (3) The power supply device for a camera according to claim (1), which is connected to an electronic circuit. A power supply device for a camera according to scope item (1) or item (2). (4) The flash circuit includes an overcharge prevention circuit that stops further charging when the charging voltage of the main capacitor reaches a predetermined threshold. ) A power supply device for the camera described in item 2. (5) The electric saw supply device for a camera according to any one of claims (1) to (4), wherein the first electronic circuit includes an exposure control circuit.