JPS602584Y2 - Cine camera electromagnetic release device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a release device for a cine camera, and more specifically to an electromagnetic release device capable of single frame photography, continuous photography, and photography mode selection.

In recent years, as demand for cine cameras has increased, improvements have been made to release devices.

Various release devices using electric control circuits have been proposed, and consumers are increasingly demanding cine cameras that can take pictures not only in frame-by-frame photography and continuous photography but also in other photography modes.

The inventor of this case has already applied for an electromagnetic release device that can take pictures for a certain period of time and take pictures after a certain period of time, but this time, it is possible to take an image at intervals of one or more frames after a preset time and then repeat the above operation. We devised an electromagnetic release device that can do this.

This interval photography is effective for photographing and recording the blooming state of flowers or the extremely slow movements of animals.

Therefore, since the length of one film in a camera is limited, it is most effective when photographing things that change over a long period of time.

As mentioned above, the purpose of the present invention is to provide an electromagnetic release device that allows shooting modes such as single-frame shooting, continuous shooting, shooting for a certain period of time, and shooting after a certain period of time, as well as interval shooting with a simple switch operation. There is a particular thing.

In order to achieve the above object, the electromagnetic release device for a cine camera according to the present invention includes an electromagnetic magnet that selects single-frame shooting or continuous shooting with a switch, and a timer that is supplied with a current signal through the release switch and reverses after a certain period of time. a circuit, an astable multivibrator changeover switch that switches the timer circuit to an astable multivibrator that reciprocates between two states, and a positive output and an inverted output signal of the timer circuit, and a signal that is supplied via the release switch. a control element that drives the electromagnetic magnet according to a signal inputted through the mode selector switch; and a control element that drives the electromagnetic magnet according to a signal inputted through the mode selector switch; and when the mode selector switch selects a signal from the release switch, normal shooting is performed; When the positive output of the circuit is selected, the photographing is stopped after a certain period of time, and when the inverted output of the timer circuit is selected, the photographing is started after a certain period of time, and the said timer circuit is controlled by the unstable multivibrator changeover switch. When switching to the unstable multivibrator, one state of the unstable multivibrator is configured to stop imaging, and the other state corresponds to the imaging state to perform interval imaging.

According to the above structure, the object of the present invention can be completely achieved.

The present invention will be explained in more detail below with reference to the drawings and the like.

FIG. 1 is a circuit diagram showing an embodiment of the present invention.

In the figure, 1 is a power supply, 2 is a release switch, 12 is a timer IC, 7, 5 and 9 are elements included in the timer circuit and determines time, 14 is a fixed resistor, and 13 is an inverter.

Reference numeral 15 denotes a photographing mode changeover switch, which can be switched to points c, d, and e using an operation dial on the outside of the camera.

16 is a circuit 1 that controls the magnet 19 of the electromagnetic release;
7 is a transistor that can control power on or off, and 18 is a switch included in the magnet control circuit 17 that switches between single frame and continuous shooting (for example, when it is off, it is continuous; when it is on, it is It becomes one piece.

) The magnet 19 is interlocked with the operation of a switch 20 and a blade stopper (not shown).

Reference numeral 21 denotes a control circuit section that always rotates the film feeding motor 22 at a constant speed.

First, operations will be explained regarding normal photography, constant time photography, and constant time non-occurrence photography.

In the case of normal shooting, the mode selection switch 15 is connected to the 0 point, so when the switch 2, which operates in conjunction with the release button, is turned on, base current is supplied via the resistor 14 and the transistor 16 becomes conductive. Become.

When current is supplied from the transistor 16, the magnet control circuit 17 is powered on and operates according to the state of the switch 18 (the magnet control circuit 17 will be described in detail later).

The magnet 19 supplied with current from the magnet 17 releases a stopper (not shown) and simultaneously turns on the switch 20, so that the filter feed motor 22 rotates at a constant speed while being controlled by the control circuit 21.

If the switch 18 is continuous (off), the magnet 19 continues to attract the stopper, and if the switch 18 is one-shot (on), the magnet 19 stops operating and releases the stopper from attracting the stopper once the shutter blade rotates once.

Then, switch 20 is returned to the off state.

Therefore, normal continuous shooting and single frame shooting can be performed.

Note that the switches 10 and 11 are interlocked switches, and may be connected to either point a or b for normal photography.

Next, a case will be described in which the photographing mode changeover switch 15 is connected to point d, and the switches 10 and 11 are connected to point a.

At the same time as the release switch 2 is turned on, power is applied to the timer circuit, and a voltage of Vcc is generated at the output terminal of the timer circuit, making the control transistor 16 conductive.

In the same manner as described above, the magnet control circuit 17 operates, the magnet 19 operates, and the film feeding motor 22 rotates.

When the time set by time setting elements 7, 8, and 9 of the timer has elapsed, the output of the timer circuit becomes almost O, so the control transistor 16 is cut off, the magnet control circuit stops operating, and the shutter blade moves to the specified stopper. When the position is reached, the film feed motor also stops.

Therefore, even if the switch 2 linked to the release button is kept on, photographing will stop after a certain period of time.

Also, connect the shooting mode switch 8 to e, and switch 10
．． When 11 is connected to point a, the output of the timer circuit is inverted by the inverter 13, so when the switch 2 is turned on, the output of the inverter 13 is approximately 0 at first, so the transistor 16 is cut off.

Therefore, the magnet control circuit 17 does not operate and the camera does not start photographing.

However, when the time set by time setting elements 7, 8, and 9 has elapsed, the output of inverter 13 becomes Vcc, transistor 16 becomes conductive, and magnet control circuit 17 becomes conductive.
operates and shooting begins.

FIG. 3 is a circuit diagram showing the configuration of the magnet control circuit 17 shown in FIG. 1.

In the figure, 27 is a capacitor, 25, 26, 30, 31
is a resistor, 28 and 32 are transistors, and 29 is a diode.

When transistor 18 is off, it is in a continuous shooting state, and when transistor 16 is conductive, transistor 28 connects resistors 25, 26,
A small amount of time, determined by capacitor 27, is off because there is not enough bias voltage across the base of capacitor 28.

Therefore, a sufficient bias current flows through the resistors 30 and 31 to the transistor 32, making it completely conductive, and a sufficient current flows to the magnet 19, attracting a stopper (not shown) and turning on the switch 20.

After a short period of time determined by the resistors 25 and 26 and the capacitor 27 has passed, the transistor 28 turns on and the voltage at point D becomes the sum of the collector-emitter saturation voltage of the transistor 28 and the forward voltage of the diode 29, and flows to the transistor 32. The current decreases.

However, if the resistor 31 is set to an appropriate value, a current sufficient to hold the magnet 19 will flow, and the stopper will continue to be held.

When the switch 18 is turned on, the transistor 28
When the transistor 32 is turned on, the transistor 32 is in a cut-off state, and if the time constant determined by the resistors 25, 26 and the capacitor 27 is appropriately selected, a -piece operation can be performed.

Next, the operation of the portion preceding the timer circuit in FIG. 1 will be explained in detail.

3 and 9 are capacitors; 4. 6. 7. 8 is resistance.

The switches 10 and 11 are interlocked with each other, and the state indicated by the dotted line (point b) indicates interval imaging, and the state indicated by the solid line (point a) indicates fixed-time imaging and fixed-time imaging.

In the terminal symbol of timer IC, DC is discharge, TH
is the threshold, TRG is the trigger, GND is the ground, PAGE is the output, Vcc is the power supply, and R is the reset terminal.

When the selector switch is set to the solid line state, when release switch 2 is turned on, capacitor 3. The transistor 5 is turned on momentarily by the resistor 4, the collector potential of the transistor 5 becomes almost 0, and the trigger terminal of the timer ICl 2 is triggered.

The output A of IC12 is connected to the resistor 7 as the power supply voltage comes out.
When the capacitor 9 is charged with current through the capacitor 8 and the charging voltage reaches the threshold voltage of the timer IC 12 after a certain period of time, the Q output becomes approximately O and photographing is stopped.

When performing interval shooting, switch 10 and 1
1 as shown by the dotted line.

Therefore, the trigger terminal is connected from the collector of the transistor 5 to the TH terminal, and the DC terminal and the TFI terminal are opened.

When the release switch is turned on, the capacitor 9 is charged via the resistors 7 and 8, and when the charging voltage reaches the threshold voltage, the output of the timer IC 12 becomes approximately 0.

At the same time, discharge begins via the capacitor 9, the resistor 8, and the DC terminal, and after a certain period of time, the output of the capacitor 12 becomes the Vcc voltage.

By repeating the above operations, a so-called unstable multivibrator operation is performed, and interval photography can be performed.

FIG. 2 shows an output waveform diagram of the inverter 13.

By changing the time of T1 using the resistor 7, waveforms of various intervals can be obtained.

Therefore, if the mode selector switch 15 is connected to point e, after an interval of T1 as shown in FIG.
The control transistor 16 is conductive only during the period 2, and a voltage is applied to the control circuit 17 of the magnet 19, so that the control circuit 17 operates.

If T2 is set to an appropriate value within the time required for one rotation of the shutter blade (not shown), interval photography of one frame or one frame becomes possible regardless of the position of the continuous changeover switch 18.

Furthermore, if the - frame or continuous changeover switch is set to the one-frame side, one-frame interval photography is possible regardless of whether the photographing mode changeover switch is connected to point d or point e.

Note that if the resistance values of resistors 7 and 8 are R7 and R8, respectively, and the capacitance of capacitor 9 is C9, then T4. T2 is the time T of the timer circuit when the mater interval selector switch 10.11 is set to the solid line position.

is T□=1. IRvC8......Given by ■.

Therefore, in the above equation, it is clear that T1. Since To can be changed, if the interval seconds and timer seconds are calibrated on the operation time ring linked to resistor 7, the operation time ring can be used in common just by switching switches 10 and 11. can do.

Further, when interval photography is performed by connecting the mode changeover switch 15 to point e, - frame, and continuous changeover switch in succession, interval photography of one frame or more is also possible by making R8 variable.

As explained above, in this invention, the timer circuit of the electromagnetic release device, which has already been applied for and which can shoot in various modes, can be switched to an unstable multi-vibration mode with a switch operation, allowing interval shooting. The conventional circuit can be used as is except for the part.

[Brief explanation of the drawing]

FIG. 1 is a circuit diagram showing an embodiment of the present invention, FIG. 2 is an output waveform diagram of the inverter 13, and FIG. 3 is a circuit diagram showing the configuration of the magnet control circuit shown in FIG. 1...W source, 2...Release switch, 3゜9.27...Capacitor, 4,6,7,
8,14.25,26,30...Resistance, 5,1
6,28.32...transistor, 10.11
...Interval selector switch, 12...
...Timer rc, 13...Inverter, 1
5...Mode selection switch, 17...
Magnet control circuit, 18...-piece, continuous shooting selector switch, 19... magnet, 20...
····switch.

Claims (1)

[Scope of utility model registration request] An electromagnetic magnet that selects single-frame shooting or continuous shooting with a switch, 1. A timer circuit that is supplied with a current signal via a release switch and reverses after a certain period of time, and an unstable multivibrator that reciprocates between two states in the timer circuit. an unstable multivibrator changeover switch for switching; a mode changeover switch for selecting a positive output signal, an inverted output signal of the timer circuit, or a signal supplied via the release switch; and a signal inputted via the mode changeover switch. When the control element that drives the electromagnetic magnet and the signal from the release switch are selected by the mode changeover switch, normal photography is performed, and when the positive output of the timer circuit is selected, photography is stopped after a certain period of time, and the timer circuit is activated. When the inverted output of the circuit is selected, imaging is started after a certain period of time, and when the timer circuit is switched to the non-stable multivibrator with the non-stable multivibrator changeover switch, one state of the non-stable multivibrator is changed. An electromagnetic release device for a cine camera, characterized by stopping shooting and performing interval shooting by making the other state correspond to the shooting state.