JPS63772B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a transmitting device that outputs a light emission signal for wirelessly causing a photographic strobe device having a receiving device to emit light.

In the case of conventional transmitting devices, the oscillation circuit of the transmitting device oscillates only after the camera's shutter button is pressed, so the radio waves that cause the photographic strobe device to emit light are generated only after the oscillating circuit starts oscillating. It takes several tens of milliseconds until the signal is output,
This has the drawback that there is a time lag between the opening of the shutter and the light emission of the photographic strobe device, making it difficult to synchronize them.

In order to solve these shortcomings, the special public
A transmitting device as shown in No. 2620 has been proposed in which a signal oscillation circuit on the camera side is kept in an oscillating state in advance, and a light emission signal is transmitted to a strobe only when the shutter button is pressed.

The present invention relates to such a transmitting device, and provides a transmitting device that transmits a carrier wave signal in advance, increases the radio wave energy of the carrier wave signal, superimposes an arbitrary specific signal, and outputs the signal by pressing a shutter button. , will be explained below with reference to the drawings.

FIG. 1 is a circuit diagram showing an embodiment of a transmitting device according to the present invention, in which 1 is a power source, 2 is a power switch, 3 is a high frequency oscillation circuit, 4 is a switch that operates in conjunction with the shutter button, and 5 1 is a capacitor, 6 is a charging circuit for charging the capacitor 5, and in FIG. 1, a resistor 7 is shown, 8 is a power amplification circuit for power amplifying the output of the high frequency oscillation circuit 3, and 9 is an antenna.

The circuit operation will be described below.

In the circuit configuration as shown in the figure, when the power switch 2 is closed, the high frequency oscillation circuit 3 starts operating because the power source 1 is supplied through the power switch 2, and the carrier wave whose power has been amplified by the power amplifier circuit 8 is transmitted to the radio wave. It is output from antenna 9 as a signal. At the same time, the capacitor 5 is charged via the a terminal of the switch 4 and the resistor 7 to a voltage value equal to the voltage V of the power supply 1.

In this state, when the shutter button of the camera is pressed, the connection state of the switch 4 is changed from the a terminal to the b terminal in conjunction with this operation. Therefore, the voltage V of the power supply 1 is applied to the resistor 7, and since this resistor 7 is connected in series with the power amplifier circuit 8 via the capacitor 5, the power amplifier circuit 8 is supplied with the voltage of the capacitor 5. The voltage that is the sum of the charging voltage V and the terminal voltage V of resistor 7
2V will be applied.

Therefore, the radio wave energy V' that was previously output from the antenna 9 via the power amplifier circuit 8 due to the voltage V of the power supply 1 is instantly doubled, extending the transmission distance and causing a little noise at short distances. It is possible to output a strong signal that is not affected by
However, since the charge in the capacitor 5 is gradually consumed by the power amplifier circuit 8, it goes without saying that the radio wave energy also gradually decreases.

FIG. 2 shows changes in the radio wave energy output from the antenna 9 in the embodiment shown in FIG. ₁ , which performs the circuit operation as described above. When the shutter button is pressed, _t1 switches switch 4 in conjunction with pressing the shutter button.
When the connection terminal of is switched from the a terminal to the b terminal, _t2 indicates the time when the shutter operation is completed and the switch 4 is switched to the a terminal as shown in FIG.

As shown in the figure, t ₀ when the power switch 2 is closed
Since the high frequency oscillation circuit 3 and the power amplification circuit 8 start operating from this time, the radio wave energy gradually increases and becomes constant at the energy V', and the switch 4 is switched from the a terminal to the b terminal by pressing the shutter button. At t ₁ , capacitor 5
The charging voltage V and the terminal voltage V of the resistor 7 are added and applied to the power amplifier circuit 8, so the radio wave energy instantly becomes 2V', and thereafter, as the capacitor 5 discharges, the radio wave energy gradually decreases. ,t ₂
If the switch 4 is switched to the a terminal again at some point, the radio wave energy also returns to the original V'.

Although the specific configuration of the power amplifier circuit 8 is not shown in the figure, for example, "CQ Publishing Co., Ltd.
Practical Electronic Circuits Handbook No. published on September 30th
By using a well-known circuit such as that shown in "Emitter grounded power amplifier circuit" shown in FIG. 3-9 on page 178, the voltage applied to the power amplifier circuit 8 and the radio wave energy have a substantially linear relationship.

The above-mentioned operation is carried out in the embodiment shown in FIG. , radio wave energy
Of course, it is provided so that it does not operate when V'.

FIG. 3 shows another embodiment of the transmitting device according to the present invention, in which the same numbers as in FIG. 1 have the same functions, 10 is a diode, 11 is a resistor, and a charging circuit 6.
includes semiconductor elements having a breakover voltage, such as a trigger diode 12 and a capacitor 13.
is added to the resistor 7 which is the charging circuit 6 shown in FIG. Although the switch 4 is linked to the depression of the shutter button, it does not perform the switching operation from the a terminal to the b terminal as shown in FIG. 1, but only performs an on/off operation.

In the circuit configuration as shown in the figure, when the power switch 2 is closed, the high frequency oscillation circuit 3 and the power amplifier circuit 8 start operating, and at the same time the diode 1
0, the capacitor 5 is charged via the resistor 7. In this state, when the shutter button of the camera is pressed, the switch 4 is turned on, so that charging of the capacitor 13 is started via the resistor 11, and the power amplifier circuit 8 receives the voltage V of the capacitor 5. A voltage added to the charging voltage of the capacitor 13 is applied, and the radio wave energy output from the antenna 9 gradually increases. Then, when the charging voltage value of the capacitor 13 reaches the breakover voltage of the trigger diode 12, the trigger diode 12 becomes conductive. When the trigger diode 12 becomes conductive, the charge stored in the capacitor 13 is released all at once. At this time, the energy consumed by the power amplifier circuit 8 while the capacitor 13 is being charged is transferred to the diode 10 and the resistor 7.
It is supplied to the capacitor 5 via. Therefore, even if the charge charged in the capacitor 13 is discharged, the charged voltage V of the capacitor 5 is applied to the power amplifier circuit 8, and the radio wave energy output from the antenna 9 simply returns to its original state. Then, once the charge in the capacitor 13 is released, the trigger diode 12 becomes non-conductive, so the capacitor 13 is charged again, and the switch 4
While it is on, the circuit operation as described above is repeated.

FIG. 4 shows the change in radio wave energy output from the antenna 9 in the circuit configuration shown in FIG. 3. In the figure, t ₀ is when the power switch 2 is on, and t ₁ is t2 indicates when the switch 4, which is linked to the pressing of the shutter button, is on, and _t2 indicates when the switch 4 is off.

As shown in the figure, when the power switch 2 is closed at t ₀ , the radio wave energy gradually increases and becomes constant at the energy V', and when the switch 4 is turned on at t ₁ , the radio wave energy decreases due to the circuit operation as described above. , increases gradually while the capacitor 13 is being charged, and when it is discharged, it undergoes a sawtooth-like change returning to the original energy V', and when the switch 4 is turned off at _t2 , the energy remains constant at the previous energy V'. Become.

Note that the period of the aforementioned sawtooth change in radio energy is determined by the time constant of the resistor 11 and the capacitor 13, assuming that the resistance value of the resistor 7 is sufficiently larger than the resistance value of the resistor 11. resistance 1
It goes without saying that adjustment can be made by using variable resistance 1 and varying the resistance value, and if it is made so that the receiving side can select a signal of any frequency, it is possible to prevent erroneous light emission by other transmitting devices. can.

FIG. 5 shows still another embodiment of the transmitting device according to the present invention, in which a well-known CL pulse generation circuit comprising a capacitor 15 and a coil 16 is connected as a charging circuit 6 for a capacitor 5.

The circuit operation in the circuit configuration as shown is as follows:
Similar to the embodiment described above, when the switch 2 is closed, the high frequency oscillation circuit 3 and the power amplifier circuit 8 start operating, and at the same time, the capacitor 5 is charged, and the switch 4 is closed in conjunction with pressing the shutter button.
When turned on, the power supply 1 is supplied to the above-mentioned CL pulse generation circuit via the resistor 14, so that a transient pulse voltage is generated. A voltage obtained by adding the above-mentioned transient pulse voltage is applied, and the radio wave energy output from the antenna 9 is output based on the above-mentioned added voltage.

FIG. 6 shows changes in the radio wave energy output from _the antenna ₉ in the circuit configuration shown in _FIG . It is the same as Figure 4.

At t ₁ , when the switch 4 is turned on in conjunction with the pressing of the shutter button, the CL pulse generation circuit as described above starts operating, so the radio wave energy output from the antenna 9 is as shown in the figure. There will be changes. In the case of the figure, since the capacitance values of capacitor 5 and capacitor 15 are the same, the peak value of radio wave energy is twice the normal value. At this time, it goes without saying that if the capacitance value of the capacitor 15 or the inductance of the coil 16 constituting the CL pulse generation circuit is made variable, the period of pulse generation can be arbitrarily adjusted.

As described above, the present invention amplifies the power of the radio wave energy outputted from the antenna 9 in advance by switching a switch in conjunction with pressing the shutter button, and in addition, this power amplification can be used to charge/discharge a capacitor or generate pulses. The purpose of the present invention is to provide a transmitting device that oscillates at an arbitrary period using a circuit, and the transmitting device according to the present invention can extend the transmission distance, and if the receiving device side can be tuned to the above-mentioned arbitrary period, it can be It has a feature that can prevent malfunctions with the transmitting device.

[Brief explanation of the drawing]

FIG. 1 is a circuit diagram showing one embodiment of a transmitting device according to the present invention, FIG. 2 shows a state of change in radio wave energy in the embodiment shown in FIG.
The figure shows another embodiment of the transmitting device according to the invention,
FIG. 4 shows the state of change in radio wave energy in the embodiment shown in FIG. 3, FIG. 5 shows still another embodiment of the transmitter according to the present invention, and FIG.
It shows the state of change in radio wave energy in the example shown in the figure. 1...Power source, 2...Power switch, 3...High frequency oscillation circuit, 4...Switch, 5...Capacitor, 6...Charging circuit, 8...Power amplifier circuit, 9...
...Antenna, 10...Diode, 11, 14...
...Resistor, 12...Trigger diode, 13...
Capacitor, 15... Capacitor, 16... Coil.

Claims (1)

[Scope of Claims] 1. A power source, a high frequency oscillation circuit connected in parallel to the power source via a power switch, a series body of a capacitor and a charging resistor, and an intervening device between the high frequency oscillation circuit and the series body. a changeover switch which normally connects the series body in parallel to the high frequency oscillation circuit, disconnects the parallel connection between the high frequency oscillation circuit and the series body by pressing a shutter button, and connects the charging resistor in parallel with the high frequency oscillation circuit; a power amplification circuit to which the output of the high frequency oscillation circuit is input and a voltage generated in the series body is applied; and an antenna connected to the power amplification circuit and outputting a carrier wave whose power has been amplified by the power amplification circuit. A light emitting signal transmitting device for a photographic strobe device. 2. A power source, a high frequency oscillation circuit connected in parallel to the power source via a power switch, a series body of a first capacitor and a charging resistor, and a diode provided between the high frequency oscillation circuit and the series body. and,
a second capacitor connected in parallel with the charging resistor; a series body of a resistor and a switch that is provided between the power source and the second capacitor and is turned on when the shutter button of the camera is pressed; a semiconductor element connected in parallel to a capacitor and having a breakover voltage; a power amplifier circuit to which the output of the high frequency oscillation circuit is input and a voltage generated in the series body is applied; and a semiconductor element connected to the power amplifier circuit and having a breakover voltage; A light emission signal transmitting device for a photographic strobe device, which consists of an antenna that outputs a carrier wave whose power is amplified by a circuit. 3. A power source, a high frequency oscillation circuit connected in parallel to the power source via a power switch, a series body of a first capacitor and a coil, and a diode provided between the high frequency oscillation circuit and the series body. , a second capacitor connected in parallel with the coil;
A series body consisting of a switch and a resistor that is provided between the power source and the second capacitor and is turned on when the shutter button of the camera is pressed, and a voltage generated in the series body when the output of the high frequency oscillation circuit is input is applied. A light emission signal transmitting device for a photographic strobe device, comprising: a power amplifying circuit; and an antenna connected to the power amplifying circuit and outputting a carrier wave amplified in power by the power amplifying circuit. 4. A power source, a high frequency oscillation circuit connected in parallel to the power source via a power switch, a series body of a first capacitor and a coil, a second capacitor connected in parallel to the coil, and the high frequency oscillation circuit. and the series body, the series body is normally connected in parallel to the high frequency oscillation circuit, and when the shutter button is pressed down, the parallel connection between the high frequency oscillation circuit and the series body is disconnected and the high frequency oscillation circuit is connected to the series body. a changeover switch that connects the coil and the second capacitor in parallel; a power amplifier circuit that receives the output of the high-frequency oscillation circuit and applies the voltage generated in the series body; A light emission signal transmitting device for a photographic strobe device, which includes an antenna that outputs a carrier wave whose power has been amplified by a power amplification circuit.