JPH0479519B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention links an operating punch to the movement of a system mechanism member to be monitored or the flow of a workpiece, and transmits a data signal corresponding to the movement of the operating punch using electromagnetic waves. The present invention relates to an operation monitoring wireless transmitter for monitoring the movement of system mechanical members or the flow of workpieces by a central control device provided on the receiver side.

(Prior art) In industrial process control systems, building equipment control systems, etc., the movements of system mechanical components such as valves and the flow of workpieces are constantly monitored.
A centrally located control device provides optimal control. In conventional systems, a large number of distributed monitoring devices are connected by wire to a central control device, and data signals detected by each monitoring device are appropriately transmitted to the central control device.

(Problem to be solved by the invention) However, in the case of the above-mentioned conventional system that connects the monitoring device and the central control device using wires, the larger the scale of the equipment, the longer the distance to run the wires becomes uneconomical. There is a problem with that. Also,
When moving or installing a new monitoring device due to changes in the system, wiring work is required to connect it to a central control device, which is complicated.

Therefore, it is desirable to wirelessly transmit data signals from monitoring devices to a central control device so that the system can be configured economically without the need for wiring work, and it is easy to move and install new monitoring devices. It will be done.

Here, in order to wirelessly transmit a data signal from a monitoring device, since there are a large number of monitoring devices, the data signal must be transmitted using a frequency division multiplex transmission method, a time division multiplex transmission method, or the like. However, in the frequency division multiplexing transmission system, as the number of monitoring devices increases and the number of channels increases, the total occupied frequency band expands.
Other equipment is likely to be adversely affected by unnecessary radiation. Furthermore, a large number of filters are required on the receiver side to separate and extract the frequency bands of each channel, and there is a problem that the system cannot be constructed at low cost. In addition, the time division multiplex transmission system requires synchronization between the monitoring device that transmits the data signal and the receiver that receives the data signal, which poses a problem in that the configuration becomes more complex.

An object of the present invention was to make it possible to wirelessly transmit data signals corresponding to the movements of system components to be monitored to a receiving side asynchronously using the same carrier frequency. An object of the present invention is to provide an operation monitoring wireless transmitting device.

(Means for Solving the Problems) In order to achieve the above object, the operation monitoring wireless transmitter of the present invention includes a mechanical section including an operating punch, and a switch that is turned ON/OFF in conjunction with the movement of the operating punch. a data output circuit that outputs a data signal that is inverted according to ON/OFF of the switching means; and a transmission signal that forms a transmission pulse train that includes a data code that encodes the data signal and a channel code unique to the device. a generation circuit; a timing circuit that causes the transmission signal generation circuit to repeatedly output the transmission pulse train a plurality of times at a predetermined period every time the data signal is inverted; a carrier wave oscillation circuit; The antenna is configured to include a modulation circuit that modulates a carrier wave using a carrier wave, and an antenna that radiates a modulated wave.

(Function) Since the carrier wave is modulated and wirelessly transmitted with a transmission pulse train containing a data code in which a data signal is inverted according to the movement of the operating punch and a channel code unique to the device, the channel code is transmitted at the receiver side. By identifying the data signal, it can be determined from which device the data signal was wirelessly transmitted.

Moreover, since the transmission pulse train is repeatedly transmitted multiple times at a predetermined period every time the data signal is inverted, accurate data signals can be received by correlating the transmission pulse trains on the receiver side.

(Example) Hereinafter, an example of the present invention will be described with reference to FIGS. 1 to 6. FIG. 1 is a block circuit diagram of an embodiment of the operation monitoring wireless transmitter of the present invention, FIG. 2 is an external perspective view of an embodiment of the operation monitor wireless transmitter of the present invention, and FIG. 2 is a schematic diagram of an example of a system in which the apparatus of FIG. 2 is used, FIG. 4 is a diagram showing an example of the configuration of a transmission pulse train wirelessly transmitted in FIG. 1, and FIG. This is a time chart explaining the operation of FIG. 1, and FIG. 6 is an explanatory diagram in which the repetition period of the transmission pulse train is varied for each channel.

First, an overview of the operation monitoring wireless transmitter of the present invention will be explained with reference to FIGS. 2 and 3. The first housing 1 houses a mechanism section 3 including an operating punch 2 and a data output circuit 4, the second housing 5 houses a transmitting circuit 7 including an antenna 6, and the data output circuit 4 and the transmitting circuit 7 Electrical connections are made as appropriate with flexible cables 8.

The first housing 1 is arranged and fixed so that the operating punch 2 is linked to the movement of the system mechanism members to be monitored or the flow of the workpiece. Also, this first
A second casing 5 is connected to the casing 1 of the receiver 9 via a flexible cable 8, and is arranged and fixed with the antenna 6 directed toward the antenna 10 of the receiver 9. A unique channel signal is assigned to each of these multiple fractionally arranged operation monitoring radio transmitting devices, and a transmission pulse train containing a channel code in which this channel signal is encoded and a data code in which a data signal is encoded. is wirelessly transmitted to the receiver 9. By identifying the channel code, the receiver 9 demodulates and determines which operation monitoring wireless transmitter the data signal is transmitted from, and sends the data signal to the central control device 11 as appropriate to monitor the system. Ru.

Next, the operation monitoring wireless transmitter of the present invention will be explained in detail with reference to FIG. 1 and FIGS. 4 to 6. A battery 20 is provided in the data output circuit 4, and power is supplied from the positive terminal of the battery 20 to each block circuit to be described later via a power supply line 21. Further, the negative terminal of the battery 20 is grounded, and the positive terminal is grounded through a resistor 22 and a reed switch 23 serving as switching means in series. A magnet 24 is configured to approach or separate from the reed switch 23 in conjunction with the operating punch 2, and the reed switch 23 is turned ON/OFF in conjunction with the operating punch 2. Then, the voltage at the connection point between the reed switch 23 and the resistor 22 is applied to the first C-MOS logic IC 26 via the integrating circuit 25. The integrating circuit 25 smoothes the chattering of the reed switch 23, and the first C-MOS logic IC 26 shapes the waveform and outputs it as a data signal. Further, a constant voltage circuit 27 and a second C-MOS logic IC 28 are connected to the power supply line 21, and a reference standard voltage is applied from the constant voltage circuit 27 to the second C-MOS logic IC 28. here,
The threshold voltage of the second C-MOS logic IC 28 is approximately 1/2 of the applied power supply voltage, and if the reference voltage is set to the threshold voltage corresponding to the lowering limit value of the terminal voltage of the battery 20. , the battery signal that is inverted when the terminal voltage of the battery 20 drops to the lowering limit value is the second C
- Output from the output terminal of the MOS logic IC 28.

Further, in the transmission circuit 7, a data signal is applied to an edge detection circuit 30 and a shift register 31 as a transmission signal generation circuit, and a battery signal is applied to the shift register 31. This shift register 31 is provided with a switch group 32 for setting a channel code unique to the monitoring device for each channel. Then, in the shift register 31, 4bit
The start code, 4-bit channel code, 1-bit data code that encodes the data signal, 1-bit battery code that encodes the battery signal, and 2-bit free space are arranged serially to form a transmission pulse train as shown in Figure 4. Ru. Also,
The edge detection circuit 30 to which a data signal as shown in FIG. 5a is applied outputs a pulse as shown in FIG.
give to The OR circuit 33 is supplied with pulses at intervals of 1 _sec , for example, as shown in FIG. 5c, from the first oscillation circuit 34, and the OR circuit 33 as shown in FIG.
The output pulse is applied to the first flip-flop 35 as a trigger pulse. And this first
When the flip-flop 35 of FIG. 5 is set as shown in _FIG . The output is as shown in FIG. 5f. Here, for convenience of explanation, FIGS. 5e and 5f are drawn with the time axis greatly extended compared to FIGS. 5a to 5d. This second oscillation circuit 37 is provided with appropriate pulse interval adjustment means 38. Then, this transmission trigger pulse is transmitted to the first counter means 39 and the second counter means 39.
is applied to flip-flop 40. When the first counter means 39 counts a predetermined number of transmission trigger pulses, for example 16, it resets the first flip-flop 35 and also enters the reset state. By resetting the first flip-flop 35, the operation of the second oscillation circuit 37 is stopped. Furthermore, a second flip-flop 4 is provided with a transmission trigger pulse from a second oscillation circuit 37.
When 0 is set as shown in FIG. 5g, the second operation control circuit 41 puts the third oscillation circuit 42 into operation and outputs clock pulses at intervals of, for example, 1 _μsec as shown in FIG. 5h. Here, Fig. 5 g, h
is shown with the time axis greatly extended compared to FIGS. 5e and 5f for convenience of explanation. The clock pulse of this third oscillation circuit 42 is applied to the second counter means 43 and also to the shift register 31. When the second counter means 43 counts the number of clock pulses necessary to send out one transmission pulse train, for example 12, it resets the second flip-flop 40 and also enters the reset state.

A transmission pulse train is applied to the modulation circuit 44 from the shift register 31 to which the clock pulse of the third oscillation circuit 42 is applied. The carrier wave oscillation circuit 45 is activated by the modulation circuit 44 in accordance with this transmission pulse train.
It is turned ON/OFF, and a carrier wave of a microwave band such as 10 GHz is turned ON/OFF and radiated from the antenna 6 as an electromagnetic wave.

Therefore, each time an inversion of the data signal is detected or a pulse is output from the first oscillation circuit 34, a predetermined number of transmission trigger pulses are output from the second oscillation circuit 37 at a predetermined period. and,
Every time the transmission trigger pulse of the second oscillation circuit 37 is output, the shift register 31 outputs one transmission pulse train to the modulation circuit 44, and repeats the transmission pulse train by the number of transmission trigger pulses of the second oscillation circuit 37. is transmitted wirelessly.

Here, the period of the second oscillation circuit 37 is set by the adjusting means 38 to a predetermined value that is different for each channel. For example, if the period T ₁ of channel 1 is
If 400 μ _sec , the period T ₂ of channel 2 is
The period T ₃ of channel 3 is assumed to be 440 μ _sec , 480 μ _sec , etc. In this way, the period T ₁ ~ of the second oscillation circuit 37
By making T _o different for each channel and setting it to a predetermined value in advance, even if the data signal is inverted on each channel at the same time and the transmission pulse trains overlap as shown in Figure 6, the transmission can be repeated. The transmitted pulse trains no longer overlap. For this reason, the receiver 9 can receive transmission pulse trains without overlapping with a high probability. Furthermore, by repeatedly transmitting the same transmission pulse train for one inversion of the data signal, the receiver 9 can receive accurate data signals by correlating the transmission pulse trains for each channel. moreover,
In addition to the inversion of the data signal, a transmission pulse train is transmitted from the operation monitoring wireless transmitter of each channel using the pulses of the first oscillation circuit 34, so that it can operate normally even if the operating pestle 2 of the operation monitor wireless transmitter is not operated. The central control device 11 can confirm that this is the case. Further, at the same time as the data signal is transmitted, a battery signal that identifies whether or not the terminal voltage of the battery 20 is at the lowering limit value is transmitted in a coded manner, so that the lowering of the terminal voltage of the battery 20 is controlled by the central control device. 11, and the battery 20 whose terminal voltage has decreased can be appropriately replaced before the operation monitoring wireless transmission device malfunctions or the like.

In the above embodiment, the battery 20 is provided as a power source, but an AC commercial power source may be suitably transformed and rectified and used as a power source.
When the battery 20 is not provided as a power source, a constant voltage circuit 27 for monitoring the terminal voltage of the battery 20 and a second C-MOS logic IC 2 are provided.
8 is unnecessary.

(Effects of the Invention) As explained above, according to the operation monitoring radio transmitting device of the present invention, a channel is assigned to each device, and a code signal that encodes a data signal corresponding to the movement of the operating punch and a code signal that is unique to the device. Since the transmission pulse train including the channel code is wirelessly transmitted, there is no need for wires to connect each device to the central control device, making it easy to move and newly install the device of the present invention. Here, the transmitted pulse train is repeatedly transmitted multiple times each time the operating punch operates, so by correlating the multiple transmitted pulse trains received on the receiver side, it is possible to ensure that the correct transmitted pulse train is received. can do. Therefore, by accurately identifying the channel code, the receiver side can determine from which device the data signal was wirelessly transmitted, eliminating the need to use frequency division multiplexing, time division multiplexing, etc. as in the past. , there is no need for a large number of filters or a complex configuration for synchronization. and,
By making the device common by using the same carrier wave frequency and allowing the channel code to be set for each channel, an excellent effect is achieved in that the wireless transmitting device can be constructed at a low cost.

[Brief explanation of the drawing]

FIG. 1 is a block circuit diagram of an embodiment of the operation monitoring wireless transmitter of the present invention, FIG. 2 is an external perspective view of an embodiment of the operation monitor wireless transmitter of the present invention, and FIG. The figure is a schematic diagram of an example of a system in which the apparatus of FIG. 2 is used, and FIG.
FIG. 5 is a time chart explaining the operation of FIG. 1, and FIG. 6 shows the repetition period of the transmission pulse train for each channel. It is an explanatory diagram made different. 4: data output circuit, 6: antenna, 7: transmitting circuit, 23: reed switch, 25: integrating circuit,
26: first C-MOS logic IC, 30: edge detection circuit, 31: shift register, 32: switch group, 35: first flip-flop, 36: first
operation control circuit, 37: second oscillation circuit, 39:
First counter means, 40: second flip-flop, 41: second operation control circuit, 42: third oscillation circuit, 43: second counter means, 44: modulation circuit, 45: carrier wave oscillation circuit.

Claims (1)

[Claims] 1 A mechanical section including an operating lever, a switch means that turns ON/OFF in conjunction with the movement of the operating lever, a data output circuit that outputs a data signal that is inverted in response to ON/OFF of the switch means, and a data output circuit that outputs a data signal that is inverted in response to ON/OFF of the switch means a transmission signal generation circuit that forms a transmission pulse train including a data code that encodes a signal and a device-specific channel code; and a transmission signal generation circuit that repeats the transmission pulse train a plurality of times at a predetermined period every time the data signal is inverted. A timing circuit for outputting a modulated wave, a carrier wave oscillation circuit, a modulation circuit for modulating a carrier wave according to the transmission pulse train that is repeatedly output a plurality of times, and an antenna for radiating a modulated wave. Operation monitoring wireless transmitter.