JP2525642B2 - Camera with strobe device - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a camera with a strobe device which has a built-in strobe device or is connected to a strobe device.

(Prior Art) Most strobe devices built in or connected to a camera use a battery (for example, DC6V) as a power source, and the power extracted from this battery is boosted by a DC-DC converter (for example, 300V) to be used as a main power source. Capacitor (eg 160μF)
Is charged once, and the charged energy is made to flow all at once through the discharge tube so that flash light is emitted.

When the main capacitor is charged, as much electric power as possible is output from the battery, so that the operating device can operate normally toward an operating device (for example, a film transport device, a shutter driving device, etc.) that requires power. It occurs that power cannot be supplied to a certain degree. For this reason, the operation of the actuating device such as the film conveying device is stopped while the strobe device is being charged (see, for example, Japanese Patent Laid-Open No. 50-97327).

(Problems to be Solved by the Invention) As described above, by forming a sequence in which charging of the strobe device and operation of the actuating device do not occur at the same time, the actuating device does not operate normally due to charging of the strobe device. It is possible to prevent the situation.

Even with the above sequence, there are few problems when taking only one shot with the camera, but when taking several consecutive shots using a strobe device, it is necessary to wait until the strobe is fully charged after taking one shot. , If the flash takes a long time to complete, you may miss an important photo opportunity or feel very messy.

In view of the above circumstances, it is an object of the present invention to provide a camera with a strobe device that does not adversely affect the operation of the actuating device of the camera and shortens the waiting time until the charging of the strobe device is completed. Is.

(Means for Solving the Problem) A strobe device-equipped camera according to the present invention includes a boosting unit that boosts primary power and outputs secondary power.
A strobe device built in the camera or connected to the camera, having a main capacitor charged by the secondary power and a light emitting section for emitting the electric power charged in the main capacitor to emit a flash light, and an operating device other than the strobe device A first mode for simultaneously supplying power to both of the strobe device and the actuating device from a power source for supplying power to the two devices, and supplying power to the strobe device from the power source and supplying power to the actuating device. And a second mode in which the secondary voltage in the second mode is higher than the secondary voltage in the first mode. Is provided with a switching means for switching to a high voltage.

Here, since the main load for the charging circuit is the main capacitor, the equivalent load for the charging circuit changes significantly as the main capacitor is charged. Therefore, "to make the secondary voltage in the second mode higher than the secondary voltage in the first mode" means that the equivalent load seen from the charging circuit to the main capacitor side has changed significantly. In this case, the secondary voltage in the second mode does not always have to be higher than the secondary voltage in the first mode, and the average voltage in each of the first mode and the second mode is A relationship is enough.

The actuating device is, for example, in the case where the camera is a camera for photographing and recording on a photographic light-sensitive material built in the camera, the photographic light-sensitive material built in the camera is conveyed in the camera, or A transport device or the like for transporting the inside of the camera to the outside of the camera, that is, an electromagnetic device or the like that mechanically operates by operating a motor, a solenoid, or the like.

Further, the above-mentioned power source does not include a commercial power source that can draw power from the camera almost indefinitely, and refers to, for example, a battery built in the camera, which has a limit to the power that can be drawn per unit time.

(Operation) In the camera with a strobe device of the present invention, in order to make the secondary voltage in the second mode higher than the secondary voltage in the first mode, the secondary voltage corresponds to the operation stop of the actuator. Since the switching means for switching the voltage to the high voltage is provided, even when the actuating device (for example, the film transport device) is operating (for example, during the film transport), an electric power that does not interfere with the operation of the actuating device is provided. While the actuator is operating, the main capacitor is drawn from the power source and charged to the main capacitor, and after the actuator has stopped operating (for example, after the film has been transported), all the power that can be extracted from the power source is directed to charging. Reduces the waiting time until charging is completed, compared to the case where charging is not performed,
It is possible to facilitate continuous shooting and reduce the chance of missing a photo opportunity.

Further, the operating device is not limited to a specific device among devices incorporated in the camera other than the strobe device or connected to the camera, but as the operating device, the photographic light-sensitive material in the camera can be used. Conveying device that conveys the film (The film feeding device that winds and rewinds the usual photographic film wound in the cartridge in the camera, the instant camera that takes instant photos, discharges the taken instant photographic film out of the camera. If the discharge device) is combined with the strobe device, the waiting time until the strobe device is completely charged can be more effectively shortened.

(Examples) Examples of the present invention will be described below with reference to the drawings.

 FIG. 3 is a front view showing an example of the outer shape of the camera.

A photographing lens 2 is provided in a substantially central portion of the camera 1, light incident from the photographing lens 2 reaches a photographic film (not shown) via a shutter (not shown), and a subject image is a photographic film. Photographed and recorded above. A photometric window 3 is provided on the left side of the taking lens 2, and the photometric window 3
The light incident from is received by an optical sensor (not shown), and the exposure is controlled according to the amount of incident light. A finder 4 is provided above and to the right of the taking lens 2 so that a subject can be observed. On the left side of the finder 4, a light projecting unit 5a and a light receiving unit 5b of a so-called active type automatic focus adjusting device are provided, and a reflected light of the light projected from the light projecting unit 5a and applied to the subject is received by the light receiving unit. The light is received by 5b, the distance to the object is measured by the principle of triangulation, and the taking lens 2 moves on the optical axis of the lens according to the distance. Further, a light emitting unit 6 of the strobe device is provided at the upper left end of the figure. When the shutter button 7 is pressed, a shutter (not shown) is operated, and strobe light is emitted from the light emitting unit 6 toward the subject in synchronization with the operation of the shutter. A self-timer switch 8 is provided below the light emitting unit 6. When the switch 8 is turned on and the shutter button 7 is pressed, self-timer photographing is performed. An exposure adjustment slide switch 9 for finely adjusting the exposure is provided above the photometry unit 3, and when the image is taken with the switch 9 slid to the left or right, it is possible to take a pale photograph as a whole according to the photographer's preference. It is possible to obtain a dark photograph as a whole. It should be noted that the camera 1 in this embodiment is an instant camera that takes an instant photograph, and a sheet-shaped instant photographic film (not shown) which is built in the camera 1 immediately after the photographing is finished and the photographing is finished by the film transport device. Is discharged to the outside of the camera from above. A battery (not shown) is built in the camera 1, and electric power is supplied from the battery to each device such as a strobe device and a film transport device in the camera 1.

FIG. 4 is a power system diagram showing an outline of a power supply system of each device incorporated in the camera shown in FIG.

The battery 10 is a strobe device 11, a photometric window 3 (see FIG. 3).
The exposure control device 12 that controls the exposure based on the light incident from the camera and the slide position of the slide switch 9 (see FIG. 3), the automatic focus adjustment device 13 that measures the distance between the camera 1 and the subject, and the shooting is completed. It is connected to a film transport device 14 for discharging the film out of the camera and a sequence control device 15 for controlling the order of the entire operation of the camera 1 and supplies electric power for operating these devices.

FIG. 5A is a circuit diagram showing the outline of the circuit of the film transport device 14 of FIG. 4, and FIG. 5B is its timing chart.

A shutter closing signal S ₁ indicating the moment when the shutter is closed at time A is input to the monostable multivibrator 141 from the exposure control device 12 of FIG. A pulse signal that falls from the monostable multivibrator 141 after a signal S ₁ ″ output from a microswitch 142 described later rises.
S ₁ ′ is output. This pulse signal S ₁ ′ is input to the OR circuit 143 from the input terminal 143a of the OR circuit 143.

In the micro switch 142, the contact 142a is connected to the + side of the battery 10 (see FIG. 4), and the contact 142b is grounded (battery
10-side is connected). The contact 142c is connected to the input terminal 143b of the OR circuit 143. This micro switch
142 is engaged with the rotation of the film transport motor 146, and is engaged with a cam 147 that makes one rotation between the start of film transport and the end of discharging the film out of the camera. As shown in the figure, the switch switching arm 1 of the micro switch 142
When 42d is in the recess 147a of the cam 147, the contact 142b and the contact 142c are connected, and when the cam 147 rotates and the switch switching arm 142d is pushed upward in the figure, the contact 142b is opened and the contact 142a. And the contact 142c are connected.

As will be described later, when the film transport motor 146 starts to rotate by the output signal S ₁ ′ from the monostable multivibrator 141, the cam 147 also rotates and the switch switching arm of the microswitch 142 before the output signal S ₁ ′ falls. 142d
Is pushed up to connect the contacts 142a and 142c, and the signal S ₁ ″ is output from the microswitch. Therefore, OR
The film transporting signal S ₂ that is the output signal of the circuit is a continuous signal from the time when the shutter close signal S ₁ is input to the time when the cam 147 completes one rotation (film discharge end) as shown in FIG. 5B. Become.

The output terminal 143c of the OR circuit 143 is connected to the base 144b of the NPN transistor 144. The emitter 144c of the transistor 144 is grounded. Collector of transistor 144 1
The coil 145d of the relay 145 is connected between 44a and the + side of the battery 10. The contact 145a of the relay 145 is connected to the + side of the battery 10, and the contact 145b is grounded. Also contact 145c
Is grounded via the film transport motor 146.

The film transport signal S ₂ is the base 144 of the transistor 144.
When input to b, the coil 145d of the relay 145 is energized, and the contact 145a and the contact 145c are connected to each other.
Rotates. When the film discharge is completed and the signal S ₁ ″ from the micro switch 142 falls, the power supply to the coil 145d of the relay 145 is cut off, the contact 145b and the contact 145c of the relay 145 are connected, and the motor 146 is stopped. To do.

The film transporting signal S ₂ is also input to the base 149b of the NPN transistor 149. Transistor 149 emitter 149
c is grounded and collector 149a is the coil of relay 148
It is connected to the + side of the battery 10 via 148d. While the film transport signal S ₂ is at H level (time A and time B in FIG. 5B)
(Between) and the coil 148d of the relay 148 is energized, and the switch 45 (contact of the relay 148) of the strobe circuit described later is switched so that the contact 148a is grounded. When the signal S ₂ during film transport falls, the contact 148b is switched to be grounded.

FIG. 1 is a circuit diagram showing an embodiment of a strobe circuit incorporated in the strobe device 11 shown in FIG.

The strobe circuit 20 is composed of a main capacitor 30, a charging circuit 40 that charges the main capacitor 30, and a light emitting unit 50 that emits flash light by discharging the electric power charged in the main capacitor 30.

After the capacitor 16 is connected to both ends of the battery 10 to stabilize the voltage, the strobe circuit is passed via the main switch 17.
Power is supplied to 20.

The emitter 4c of the PNP transistor 41 is the main switch 17
Connect to + side 10a of battery 10 via
Connect with 0 ". ) Has been. The base 41b of the transistor 41 is connected to one end a of the secondary winding 42b of the boosting transformer 42. A capacitor 43 is inserted between the emitter 41c and the base 41b of the transistor 41. One end 44a of the resistor 44 is connected to the base 41b of the transistor 41, and the other end 44b is connected to the minus side 10b of the battery 10 (hereinafter,
Call it "ground". The indefinite point connected to the negative side 10b of the battery 10 is called a ground point e. ) Has been. The collector 41a of the transistor 41 is the primary winding 42a of the boosting transformer 42.
Is connected to one end b. A capacitor 44 is connected between the emitter 41c of the transistor 41 and the other end c of the secondary winding 42b of the transformer 42. The other end d of the primary winding of the transformer 42 and the intermediate terminal f are selectively grounded by a switch 45. The other end c of the secondary winding 42b is connected to the anode 46a of the diode 46, and the cathode 46b of the diode 46 is connected to the + side 30a of the main capacitor 30. The negative side 30b of the main capacitor 30 is grounded.

A resistor 51 and a neon tube 52 are connected in series to both ends 30a and 30b of the main capacitor 30. A flash discharge tube 53 is connected to both ends of the main capacitor 30. One end of resistor 54
54a is connected to the + side 30a of the main capacitor 30. resistance
The other end 54b of 54 is connected to one of transformer 56 via capacitor 55.
It is connected to one end i of the next winding 56a. The other end j of the primary winding 56a is grounded together with one end k of the secondary winding 56b.
The other end 1 of the secondary winding 56b is the trigger electrode 53a of the flash discharge tube 53.
Is connected to Between the other end 54b of the resistor 54 and the ground point e, there is connected a contact x which closes at the timing at which the strobe emits light in conjunction with the operation of the shutter of the camera.

Next, the operation of the flash circuit 20 configured as above will be described.

In addition to supplying electric power from the battery 10 to the strobe circuit 20, the film transport device 14 (see FIGS. 5A and 5B), which is an example of the actuating device in the present invention, discharges the film built in the camera to the outside of the camera. In the first mode in which power is simultaneously supplied to the primary winding 42 of the boosting transformer 42,
The switch 45 is switched so that the other end d of the a is grounded, the boosting ratio in the boosting transformer 41 is lowered, and the main capacitor 30 is charged with a low voltage. Film transport device
When 14 stops, the battery 10 supplies power to the strobe circuit 20 and shifts to a second mode in which power is not supplied to the film transport device 14, and in this second mode, 1
The switch 45 is switched so that the intermediate terminal f of the secondary winding 42a is grounded, and the main capacitor 30 is charged with a higher voltage than in the first mode. The charging circuit 40 constitutes a blocking oscillator, and when the main switch 17 is closed, the capacitor 43 is repeatedly charged and discharged to convert direct current input from the power source 10 into alternating current, which is boosted by the step-up transformer 42. , Is rectified by the diode 46 and the main capacitor 30 is charged.

When the main capacitor 30 reaches a predetermined voltage (for example, 270 V) that allows flash photography, current flows through the neon tube 52 via the resistor 51, the neon tube 52 lights up, and the photographer is informed that the neon tube 52 has been charged. Reportedly. At the same time that the main capacitor 30 is charged, the capacitor 55 is also charged via the resistor 54.

After the charging is performed as described above, when the shutter button 7 (see FIG. 3) is pressed, the shutter of the camera operates and the X contact 60 is closed in conjunction with this operation. When the X contact 60 is closed, the connection point between the resistor 54 and the capacitor 55 is grounded, so that one end i of the primary winding 56a of the transformer 56 is
Becomes a negative voltage instantaneously, and a current flows from the other end j to the one end i. Due to this current, a high voltage is generated on the secondary side of the transformer 56, and this high voltage is applied to the trigger electrode of the flash discharge tube 53, whereby the charge charged in the main capacitor 30 is changed. Flow momentarily via
Flash light (strobe light) is emitted from the flash discharge tube 53.

As described above, the switch 45 is operated in the first mode (from the battery 10 to the flash circuit 20 and the film transport device 14).
In the mode for supplying electric power to both of the above, and the other end d of the primary winding 42a of the step-up transformer 42, the step-up ratio is kept lower than in the second mode described later. The electric power per unit time input from the battery 10 to the strobe circuit 20 is limited to such an extent that the operation of the film transport device is not affected. The equivalent load seen from the charging circuit 40 varies greatly depending on the state of charge of the main capacitor 30, and even if the boost ratio of the boosting transformer 42 is low,
When 30 is uncharged, a large current flows momentarily,
Since the time when a large current flows is momentary, by selecting the capacitor 16 having an appropriate capacity, it is possible to prevent the operation of the film transport device 14 from becoming abnormal due to this momentary large current.

When the film transport device 14 is stopped, the mode is changed from the first mode to the second mode, and as described above, the intermediate terminal f is grounded at the trailing edge of the film transport signal S ₂ (see FIG. 5A). The switch 45 is switched and the boost ratio is increased, so that the main capacitor 30 is rapidly charged to an appropriate high voltage.

In this way, even during the operation of discharging the film out of the camera immediately after the shooting of one shot is finished,
By starting charging to the extent that this operation is not a problem, the waiting time until the next shot can be reduced.

In the above embodiment, the circuit 45 shown in FIG. 5A is used to switch the switch 45 by using the signal S ₂ during film transport.However, the switch 45 is switched by changing the value of the current flowing through the motor 146, for example. It is also possible to detect the end of the discharge of the film by detecting it and switch the switch 45 accordingly (see Japanese Patent Laid-Open No. 545682/1979, and winding of a normal photographic film wound in a cartridge). For detection at the end, see Japanese Patent Laid-Open No. 52-34718). Furthermore, when the film is transported outside the camera, the switch 45 is closed while the gap between the developing rollers that rotate by sandwiching the film is narrow (when the film is not between the rollers), and when the gap between the developing rollers is wide (the film is The deploying roller and the switch 45 may be mechanically interlocked so as to open the switch 45 (when they are located between the deploying rollers). As described above, the interlocking means for operating the film transport device 14 and switching the switch 45 is not limited to a specific means, but can be variously configured.

Next, an example of the result of an experiment conducted by the present inventor using the slobo circuit 20 and a general film transport device is shown below.

FIGS. 2A and 2B show charging of the strobe device when the film transport device and the strobe device are independently operated with a certain time, and while the film transport device is operating by the circuit shown in FIG. It is the figure which showed an example of the time change of the electric current and voltage when performing. The horizontal axis j is the time axis. Further, I ₁ shown in FIGS. 2A and 2B indicates the magnitude of the primary current flowing from the power source. V and I ₂ respectively represent the voltage across the main capacitor 30 of the strobe circuit 20 and the secondary current flowing into the main capacitor 30.

The portion A shown in FIG. 2A shows the primary current I ₁ when only the film transport device is operated. Time t ₁ until one film after the film transport device starts the operation (time t _A) is discharged to the outside of the camera was t ₁ = 2.2 seconds.. The portion B shown in FIG. 2A indicates that the strobe circuit is in the charging operation, and the charging is started immediately after the main switch 17 is closed (time t _B ) and the main capacitor 30
The voltage V across the voltage rises with time. Voltage V is 270V from the start of charging the above strobe
The time t ₂ required to reach (lighting voltage V ₂ of neon tube 66) is t ₂
= 5.8 (seconds). Therefore, if the charging is stopped while the film transport device is operating, the time t from the end of shooting one shot until the next shooting is possible is
t = t ₁ + t ₂ = 2.2 + 5.8 = 8.0 (seconds).

FIG. 2B shows that the operation of the film transporting apparatus is started from time t _{c, and} the charging of the main capacitor 30 is started to the extent that this operation is not disturbed, and the operation of the film transporting apparatus is stopped at time t _d , Primary current I ₁ and main capacitor when the boosting ratio of boosting transformer 42 is increased to charge
FIG. 6 is a diagram showing a voltage V across both ends of the capacitor 30 and a secondary current I ₂ flowing into the main capacitor 30. Here, the voltage across the main capacitor 30 at time t _d is V ₃ (for example, 150 V), and
In the figure, assuming that the time interval from the time t _B until the voltage across the main capacitor 30 becomes V ₃ is t ₀ , after the film which has been taken is discharged by the film transport device to the outside of the camera, the neon tube 52 The time until lights up is shortened by t ₀ .

According to an example of the experimental results, the time t ₁ ′ for discharging one film is t ₁ ′ = 2.3 (seconds), the time until the voltage V reaches the lighting voltage V ₂ of the neon tube after the film transport device is stopped.
t ₂ ′ is t ₂ ′ = 4.8 (seconds), and the time t ′ from the end of shooting one shot until the next shooting becomes t ′ =
t ₁ ′ + t ₂ ′ = 2.3 + 4.8 = 7.1 (seconds), which is 0.9 seconds shorter than the above t.

In addition, most photographers do not want to take the next shot while the film that has already been shot is being conveyed, so whether or not the photographer feels messed up by the slow charging of the strobe is a problem. A problem is the length of time from the end of conveyance to the completion of timed strobe charging (lighting of the neon tube 66 (see FIG. 1)). From this point of view, comparing the above data, t ₂ = 5.8 (sec) and t ₂ ′ = 4.8 (sec), and t ₂ −
t ₂ ′ = 1.0 (second) has been shortened.

In the above embodiment, the device for discharging the sheet-shaped photographic film to the outside of the camera was described as the film transporting device, but the film transporting device is a hoisting device for winding up the ordinary photographic film wound in the cartridge. Of course, you can. The actuating device in the present invention is not limited to the film transport device, and the present invention can be applied to the case where other various devices requiring electric power are actuated simultaneously with the strobe device.

Further, the camera with a strobe device of the present invention is not limited to a conventional camera (a so-called compact camera, a single-lens reflex camera, an instant camera, etc.) for photographing on a photographic light-sensitive material, and for example, an electronic still camera, a video camera, etc. It can also be applied to other cameras that do not use photographic light-sensitive materials.

(Effects of the Invention) As described in detail above, the camera with a strobe device of the present invention supplies power to the strobe device from the power supply in the first mode in which power is simultaneously supplied from the power supply to the strobe device and the operating device. Along with the second mode in which no power is supplied to the operating device, the operation device is stopped so that the secondary voltage in the second mode is higher than the secondary voltage in the first mode. Since the switching means for switching the secondary voltage to the high voltage is provided correspondingly to the above, it is possible to shorten the waiting time until the charging of the strobe device is completed without adversely affecting the operation of the above operating device of the camera. it can.

Further, when the film transport device is the above operating device,
The waiting time can be shortened more effectively.

[Brief description of drawings]

FIG. 1 is a circuit diagram showing an embodiment of a strobe circuit incorporated in a strobe device, and FIGS. 2A and 2B are respectively a diagram of a film transport device and a strobe device when they are operated independently and of a film. When the transport device and strobe device are operated simultaneously,
A front view showing an example of changes in voltage and current with time, FIG. 3 is a front view showing an example of the outer shape of the camera, FIG. 4 is a power system diagram of the camera shown in FIG. 3, FIG. 5A, FIG. FIG. 5B is a circuit diagram schematically showing a circuit of the film transport device, and a timing chart thereof. 1 ... Camera, 2 ... Photographing lens 3 ... Photometric window, 4 ... Viewfinder 5 ... Strobe light emitting part, 7 ... Shutter button 10 ... Battery, 14 ... Film transport device 17 ... Main switch, 20 ...... Strobe circuit 30 …… Main capacitor, 40 …… Charging circuit 42 …… Boosting transformer, 50 …… Light emitting part 53 …… Flash discharge tube, 60 …… X contact

Claims (1)

(57) [Claims] 1. A booster for boosting a primary power to output a secondary power, a main capacitor charged by the secondary power, and a light emission for emitting a flash light by discharging the power charged in the main capacitor. A strobe device built in the camera or connected to the camera, and an actuating device other than the strobe device, and a power supply for supplying power to both the strobe device and the actuating device to these two devices at the same time. A first mode for supplying electric power and a second mode for supplying electric power from the power source to the strobe device but not supplying electric power to the actuating device, and a secondary voltage in the first mode And a switching means for switching the secondary voltage to a high voltage in response to the operation stop of the operating device so that the secondary voltage becomes a high voltage in the second mode. Flash device with a camera according to symptoms.