JPH0442850B2 - - Google Patents

Description

Detailed Description of the Invention (Industrial Field of Application) The present invention enables an oscillation circuit to oscillate only the number of output pulses necessary for a shift register to output one transmission pulse train, thereby reducing power consumption due to the oscillation operation. This invention relates to an oscillation operation control device that reduces the number of oscillations.

(Prior Art) In industrial process control systems, building equipment control systems, and the like, a large number of monitoring devices that monitor the movement of system mechanical members such as valves and the flow of workpieces are appropriately distributed. Data signals corresponding to the movement of the system mechanical members, the flow of workpieces, etc. are transmitted from the monitoring device to the central control device, and the central control device optimally controls the system.

In conventional systems, a large number of distributed monitoring devices and a central control device are connected by wires, and data signals are transmitted, power supply voltage is supplied, etc. via these wires.

However, in a system that connects a monitoring device and a central control device by wire, the larger the scale of the equipment, the longer the distance the wire must be routed, making it uneconomical. Further, when moving or installing a new monitoring device due to a system change, etc., there is a need for wiring work to connect it to a central control device, which is complicated.

Therefore, it is desired to eliminate the need for wires connecting the monitoring device and the central control device, and to wirelessly transmit data signals from the monitoring device to the central control device. Furthermore, in order to simplify the work of arranging this monitoring device, it is desirable to have a built-in battery as a power source.

By the way, in the case of a general wireless transmitter,
The operation of the carrier wave oscillation circuit is turned ON/OFF by the modulation circuit according to the transmission pulse train incorporating the data signal to be transmitted, and the modulated wave consisting of the disconnection of the carrier wave is wirelessly transmitted. A clock pulse generated by the transmission trigger pulse is then applied to the shift register, and a transmission pulse train is appropriately output from the shift register to the modulation circuit.

(Problems to be Solved by the Invention) In the conventional general wireless transmitter described above, a clock pulse is oscillated from an oscillation circuit that is always in operation, and a gate or the like is opened and shifted in response to a transmission trigger pulse. The structure is such that clock pulses are appropriately applied to registers and the like. For this reason, a clock pulse is always oscillated regardless of the presence or absence of wireless transmission, and power is wasted due to unnecessary operation of this oscillation circuit. For devices that use a battery as a power source, the wasteful power consumption caused by this oscillation circuit shortens the life of the battery, and the problem is that the battery must be replaced frequently and maintenance is complicated. be.

The purpose of the present invention was to reduce the power consumption due to the oscillation operation by causing the shift register to oscillate only the number of output pulses necessary for outputting one transmission pulse train. An object of the present invention is to provide an oscillation operation control device.

(Means for Solving the Problems) In order to achieve the above object, the oscillation operation control device of the present invention includes: an oscillation circuit; a shift register that receives output pulses from the oscillation circuit and outputs a transmission pulse train; A flip-flop that is set by the input of a trigger pulse, an operation control circuit that switches the oscillation circuit into an operating state using the set output of this flip-flop, and a shift register that counts the output pulses of the oscillation circuit and generates one transmission pulse train. and a counter circuit for resetting the flip-flop with the number necessary for output.

(Function) Therefore, when the flip-flop is set by one trigger pulse and the oscillation circuit is activated, and the shift register oscillates a predetermined number of output pulses necessary to output one transmission pulse train, The flip-flop is reset by the counter circuit and the operation of the oscillation circuit is stopped. Therefore, only the predetermined number of output pulses required for the shift register to output one transmission pulse train in response to one trigger pulse are oscillated, and the output pulses other than the predetermined number of output pulses are During this period, the oscillation circuit is inactive and no power is consumed.

(Example) Hereinafter, an example of the present invention will be described with reference to FIGS. 1 to 5. FIG. 1 is a block circuit diagram of an operation monitoring wireless transmitter using an embodiment of the oscillation operation control device of the present invention, and FIG.
FIG. 3 is a schematic diagram of an example system in which the device shown in FIG. 2 is used, and FIG.
FIG. 5 is a diagram showing an example of the configuration of a transmission pulse train that is wirelessly transmitted; FIG. 5 is a time chart for explaining the operation of FIG. 1;

First, an overview of the operation monitoring wireless transmitter will be explained with reference to FIGS. 2 and 3. In the first case 1,
A mechanism section 3 including an operating rod 2 and a data output circuit 4 are housed, a transmitting circuit 7 including an antenna 6 is housed in the second housing 5, and the data output circuit 4 and the transmitting circuit 7 are housed in a second housing 5.
are appropriately electrically connected by a flexible cable 8.

The first casing 1 is arranged and fixed so that the operating rod 2 is interlocked with 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 many distributed operation monitoring radio transmitting devices, and a transmission pulse train containing a channel code encoded with this channel signal and a data code encoded with a data signal is assigned. 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 signal to the central control device 11 as appropriate to monitor the system. .

Next, the operation monitoring wireless transmitter will be explained in more detail with reference to FIGS. 1, 4, and 5. 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 connected to the resistor 22 and reed switch 23.
is connected in series to ground. A magnet 24 is constructed to approach or separate from the reed switch 23 in conjunction with the operating rod 2, and the reed switch 23 is turned ON/OFF in conjunction with the operating rod 2. And this reed switch 23 and resistor 22
The voltage at the connection point is applied to the first C-MOS logic IC 26 via the integrating circuit 25. This integration circuit 25 smoothes the chattering of the reed switch 23 and further smooths the chattering of the first C-MOS logic IC.
The signal is waveform-shaped at 26 and output as a data signal. Further, the power supply line 21 includes a constant voltage circuit 27 and a second
The second C-MOS logic IC 28 is connected, and the reference voltage is supplied from the constant voltage circuit 27 to the second C-MOS logic IC.
Given to 28. Here, the threshold voltage of the second C-MOS logic IC 28 is approximately 1/2 of the applied power supply voltage, and the reference standard voltage is set to the threshold voltage corresponding to the lowering limit value of the terminal voltage of the battery 20. If set, the battery signal that is inverted when the terminal voltage of the battery 20 drops to the lowering limit value is output to the second C-MOS logic IO2.
It is output from the output terminal of 8.

Further, in the transmitting circuit 7, a data signal is given to an edge detection circuit 30 and a shift register 31, and a battery signal is given 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, the 4-bit start code, 4-bit channel code, and data signal are encoded.
A transmission pulse train as shown in FIG. 4 is formed in which a 1-bit data code, a 1-bit battery code encoded as a battery signal, and 2-bit free space are serially arranged. Further, the edge detection circuit 30 to which a data signal as shown in FIG. 5a is applied provides a trigger pulse as shown in FIG. 5b to the OR circuit 33 when the rising and falling edges are reversed. The OR circuit 33 is supplied with a trigger pulse, for example, at 1 _sec intervals, as shown in FIG. Given as a trigger pulse. When the first flip-flop 35 is set as shown in FIG.
Output pulses are output at intervals of 400 _μsec as shown in Figure 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 3
7 is provided with appropriate pulse interval adjustment means 38. This output pulse is then applied to the first counter means 39 and the second flip-flop 40. The first counter means 39 is, for example,
When a predetermined number of output pulses, such as 16, are counted, the first
At the same time, the flip-flop 35 of the flip-flop 35 is reset, and the flip-flop 35 is also reset. By resetting the first flip-flop 35, the second oscillation circuit 37
operation is stopped. Furthermore, the second oscillation circuit 3
When the second flip-flop 40 to which the output pulse from the oscillator 7 is applied as a trigger pulse is set as shown in FIG. For example, output pulses at intervals of 1 _μsec as shown in Figure h. Here, for convenience of explanation, FIGS. 5g and 5h are drawn with the time axis significantly extended compared to FIGS. 5e and f. The output pulse of this third oscillation circuit 42 is applied to the second counter means 43 and also applied to the shift register 31 as a clock pulse. Second counter means 4
3 is the second output pulse when counting the number of output pulses required to send out one transmission pulse train, such as 12 pulses.
At the same time, the flip-flop 40 of the third oscillation circuit 4 is reset, and the third oscillation circuit 4 is also reset.
2 is stopped.

A transmission pulse train is given to the modulation circuit 44 from the shift register 31 to which the pulses of the third oscillation circuit 42 have been given, and the carrier wave oscillation circuit 45 is turned ON/OFF by the modulation circuit 44 according to this transmission pulse train.
Then, a carrier wave in 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 trigger pulse is output from the first oscillation circuit 34, a predetermined number of output pulses are output from the second oscillation circuit 37 at a predetermined period. and,
Every time the output pulse of the second oscillation circuit 37 is output, the shift register 31 outputs one transmission pulse train to the modulation circuit 44, and the second oscillation circuit 37
The transmission pulse train is wirelessly transmitted repeatedly by the number of output pulses.

Here, since both the first and second oscillation circuits 34 and 37 stop operating after outputting a predetermined number of output pulses, they do not output unnecessary output pulses, which reduces power consumption accordingly. The lower the duty in the operating state, the lower the average power consumption.

Further, the period of the second oscillation circuit 37 is set by the adjustment 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 signals of each channel are inverted at the same time and the transmission pulse trains overlap, the repeatedly transmitted transmission pulse trains will overlap. It will stop happening. 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. Furthermore, since the transmission pulse train is transmitted from the operation monitoring wireless transmitter of each channel by the pulse of the first oscillation circuit 34 in addition to the inversion of the data signal, it is possible to operate normally even if the operating rod 2 of the operation monitor wireless transmitter is not operated. The central control device 11 can confirm that the system is operating properly. Furthermore, at the same time as transmitting the data signal, the battery 20
Since the battery signal identifying whether the terminal voltage of the battery 20 is at the lowering limit value is transmitted in a coded manner, the central control device 11 can identify a drop in the terminal voltage of the battery 20, and the battery 20 with a lower terminal voltage can be detected. 20 can be replaced appropriately before the operation monitoring wireless transmitter malfunctions or the like.

In the above embodiment, each time the data signal is inverted and a pulse is output from the edge detection circuit 30 or a pulse is output from the first oscillation circuit 34, a predetermined number of pulses are output from the second oscillation circuit 37. The shift register 31 is configured so that output pulses are output and a transmission pulse train is repeatedly output from the shift register 31 by the number of output pulses, but one transmission pulse train is output every time the data signal is inverted. Of course, it is also a good thing.

(Effects of the Invention) As explained above, according to the oscillation operation control device of the present invention, the oscillation circuit has a predetermined number of pulses necessary for the shift register to output one transmission pulse train in response to one trigger pulse. Since the operation is stopped after the output pulse is oscillated, unnecessary output pulses are not output, and power consumption is reduced accordingly. The lower the duty at which the oscillation circuit is in operation, the lower the power consumption, and the average power consumption of an oscillation circuit that is intermittently in operation, such as in an operation monitoring wireless device using the oscillation operation control device of the present invention, is extremely low. Become something. Therefore, it is suitable for a device including an oscillation circuit powered by a battery.

[Brief explanation of drawings]

FIG. 1 is a block circuit diagram of an operation monitoring radio transmitter using an embodiment of the oscillation operation control device of the present invention, and FIG. 2 is an embodiment of the operation monitoring radio transmitter of FIG. FIG. 3 is a schematic diagram of an example system in which the device shown in FIG. 2 is used, and FIG. 4 shows an example of the configuration of a transmission pulse train wirelessly transmitted in FIG. 1. FIG. 5 is a time chart explaining the operation of FIG. 1. 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.

Claims (1)

[Claims] 1. An oscillation circuit, a shift register that receives output pulses from this oscillation circuit and outputs a transmission pulse train, a flip-flop that is set by the input of a trigger pulse, and a set output of this flip-flop that switches the oscillation circuit into an operating state. The present invention is characterized by comprising an operation control circuit and a counter circuit that counts the output pulses of the oscillation circuit and resets the flip-flop with the number necessary for the shift register to output one transmission pulse train. Oscillation operation control device.