JPH0247796B2 - MEETASENSA - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a meter sensor, and particularly to a meter sensor for automatically reading the amount of water, gas, electricity, etc. used via a communication line.

In order to automatically read the amount of water, gas, electricity, etc. used by each user from a meter reading center via a communication line, a meter is equipped with a signal generator that sends an electrical signal indicating the flow rate, and a meter is equipped with a signal generator that sends an electrical signal indicating the flow rate. A meter sensor has been developed that generates an electrical signal indicating an integrated flow rate from an incoming electrical signal and sends the electrical signal indicating the integrated flow value to a communication line in response to a call signal from a meter reading center. At the meter reading center, the integrated flow rate value for each user can be detected by the electrical signals sent from each meter sensor, and therefore the amount used in a predetermined period can be known. The meter signal generator is
A magnetic sensor element detects the rotational speed of a magnet attached to a rotating body that rotates at a speed proportional to the flow rate per unit time, and sends out a pulse signal having a pulse number proportional to the flow rate. The meter sensor that receives this pulse signal generates a digital signal indicating the integrated flow rate by counting the number of pulses, sends this to the meter to display the integrated flow value, and also responds to the call signal from the meter reading center. A digital signal indicating the integrated flow rate value is sent to the communication line.

The conventional meter sensor described above operates as a terminal device that performs automatic meter reading by transmitting a flow rate integration signal when called from a meter reading center via a communication line. Using conventional meter sensors, in situations where a single building houses many users, such as apartment complexes or shared-use buildings, a meter is installed for each user and each meter is automatically read from a meter reading center. In this case, it is uneconomical to connect a communication line from the meter reading sensor to each meter sensor individually, so it is necessary to connect an additional device between the communication line and multiple meter sensors to increase the number of meters used. are doing.

FIG. 1 is a block diagram showing a case where a plurality of meter sensors are connected to one communication line via the above-mentioned additional device. The meter sensor 1 counts the pulse signals sent from the meter 2 and generates a digital signal indicating the accumulated flow rate, and when it receives a call signal from the additional device 3, generates a digital signal indicating the accumulated flow rate. It is sent to the additional device 3. The additional device 3 receives the command signal sent from the meter reading center via the communication line, sends a call signal to one of the plurality of connected meter sensors 1 designated by the command signal, and calls that meter sensor. A digital signal indicating an integrated flow rate value sent from 1 is sent to a meter reading center via a communication line.

When a plurality of conventional meter sensors are connected to one communication line, a separate means must be provided to select the desired meter sensor and send and receive signals, like the additional device 3 in the above explanation. This not only occupies extra installation space, but also
When adding additional equipment to add a new meter sensor in addition to the existing meter sensor,
There is a problem in that a large amount of man-hours are required for installation and testing.

An object of the present invention is to solve the above-mentioned problems, and even when a plurality of meter sensors are connected to one communication line, it is possible to achieve desired results without requiring any extra equipment and by adding a circuit with a small number of parts. To provide a meter sensor capable of transmitting and receiving signals by selecting one of the meter sensors.

The meter sensor of the present invention includes an integrating means that receives a pulse signal indicating a flow rate measurement value given from a meter, counts the pulse signal, and sends an integrated signal indicating an integrated flow value, and a predetermined predetermined value including at least the integrated signal. a signal generating means for sending out a response signal including one of the signal groups, and at least one terminal for connecting an external meter sensor, and selecting any one of the terminals to switch the connection. a switching means; and an input/output means for generating a control signal in response to an operation request signal given from an external device and transmitting a response signal sent from the signal generating means and the terminal to the external device; at most one external meter sensor is connected to each said terminal of the switching means;
When the control signal requests sending of the answer signal from the signal generating means, the answer signal is sent to the input/output means, and the control signal causes switching of connection of any one of the external meter sensors. When a request is made, the connection between the external meter sensor and the input/output means is switched by switching the connection of the terminal of the switching means, and the input/output signal is transmitted to the external meter while the external meter sensor is connected. The signal is transferred to the meter sensor, and the response signal from the meter sensor is sent to the input/output means.

Next, the present invention will be explained in detail with reference to the drawings.

FIG. 2 is a block diagram showing one embodiment of the present invention. The counter 4 of the meter sensor 1 is
A flow rate signal having a number of pulses proportional to the flow rate is received from the flow rate signal, and by counting the pulses, an integrated signal of parallel pulses indicating the integrated value of the flow rate is generated and sent to the message assembly circuit 5. Command signals and activation signals are sent from the communication line via the input/output terminal 9. The command signal consists of serial pulses in a predetermined format, and is used to send a telegram signal including the integrated signal of the meter sensor 1, connect or disconnect the relay end 10 or 11, and connect or disconnect the meter sensor connected to the relay end 10 or 11. It includes a code requesting transmission of one of the telegram signals including the integration signal. Command signals and activation signals sent from the input/output terminal 9 are sent to the control circuit 7 through the input/output circuit 6. The input/output circuit 6 includes a switch circuit that connects command signals and activation signals sent from the input/output terminal 9 to a control circuit 7, and a switch circuit that receives a message signal from the message assembly circuit 5 or the switching circuit 8. and a switch circuit for connecting them to the input/output terminal 9. When a command signal is sent from the input/output circuit 6 requesting the transmission of a telegram signal including the integration signal of the meter sensor 1, the control circuit 7 generates a selection signal indicating transmission of the integration signal, and also generates a selection signal along with the command signal. In response to the sent activation signal, a control signal for controlling the transmission of the message signal is generated, and the selection signal and the control signal are made in parallel and sent to the message assembly circuit 5. Relay end 10 (or 11)
When a command signal requesting connection to the relay end 10 (or 11) is sent, the control circuit 7 generates a selection signal indicating connection to the relay end 10 (or 11), sends this to the switching circuit 8, and also 11 and a control signal for sending a corresponding message signal to the message assembly circuit 5. Furthermore, when a command signal to disconnect the relay end 10 (or 11) is sent, the control circuit 7 sends a selection signal to the switching circuit 8 to disconnect the connection to the relay end 10 (or 11). The control circuit 7 connects the switching circuit 8 to the relay end 10 (or 1
1) After sending the selection signal indicating the connection to the relay terminal 10 (or 11), the switching circuit switches the command signal and start signal sent from the input/output circuit 6 until the selection signal is sent to disconnect the connection to the relay terminal 10 (or 11). 8 in parallel with the selection signal, and in between, the relay terminal 1
After sending the control signal for sending the message indicating the start of connection to 0 or 11, the message assembly circuit 5
Stop sending control signals to. Switching circuit 8
receives a selection signal indicating connection of the relay end 10 (or 11), and then selects the relay end 10 (or 11).
1) is provided with a switch circuit that connects the command signal and activation signal sent from the control circuit 7 to the relay terminal 10 (or 11) until it receives a selection signal to disconnect the connection to the relay terminal 10 (or 11). Relay end 10 or 1
1 are each connected to an external meter sensor, and when one of the meter sensors is connected by a switching circuit 8 and receives a command signal and a start signal requesting transmission of a telegram signal including the integration signal, The telegram signal containing the meter sensor integration signal is sent to the input/output circuit 6 through the switching circuit 8, and further sent to the communication line via the input/output terminal 9. On the other hand, when the message assembly circuit 5 receives the selection signal indicating sending of the meter sensor's integration signal and the control signal for sending the message signal, it reads the integration signal sent from the counter 4 in response to these signals. Then, a telegram signal in a predetermined format containing the data is generated and sent to the input/output circuit 6. When the message assembly circuit 5 receives the selection signal indicating the start of connection to the relay end 10 or 11 and the control signal for transmitting the message signal, it includes a signal indicating the start of connection to the relay end 10 in response to these signals. A telegram signal in a predetermined format is generated and sent to the input/output circuit 6. The message signals sent from the message assembly circuit 5 to the input/output circuit 6 are all sent from the input/output terminal 9 to the meter reading center via the communication line.

3 and 4 are a block diagram showing an example of the configuration of the control circuit 7 in the meter sensor 1 of FIG. 1, and a time chart illustrating its operation, respectively. The signal a sent from the input/output circuit 6 includes command signals D1, D2, D3, and D4 and a pulse activation signal that rises after them, and is sent to the signal separation circuit 12 and switch circuit of the control circuit 7. 20. Signal separation circuit 20
separates the command signal and activation signal included in signal a, converts the serial pulse command signal into parallel pulses, sends them to the decoder circuit 13, and sends the activation signal to one input terminal of the inhibition gate 14. Apply. When the received parallel command signals (corresponding to command signals D1 and D3) request transmission of a telegram signal including an integration signal, the decoder circuit 13 sends a signal b
When a parallel command signal (corresponding to the command signal D2 or D4, respectively) requesting the connection or disconnection of the relay end 10 (or 11) in FIG. 2 is received, the connection is made. A pulse that rises when a request is made and falls when a disconnection request is made is generated in the signal f (or i). signal f
and i pass through the OR gate 19 and become the OR signal, which is sent to the switch circuit 20, and only while the pulse is rising, connects the signal a and sends it out as the signal g. It is applied to the input terminal and the leading edge detection circuit 21.
The leading edge detection circuit 21 rises at the rising edge of the pulse of the received signal and generates a pulse having a predetermined time width, and sends it to the other input terminal of the exclusive OR gate 22 as a signal c. send. When the signal sent from the exclusive OR gate 22 to the inhibition gate 14 is at a high level (hereinafter abbreviated as H), the activation signal sent from the signal separation circuit 12 is sent to the leading edge detection circuit 15. When the signal is at a low level (hereinafter abbreviated as L), the activation signal is allowed to be sent to the leading edge detection circuit 15. When a rising edge of a pulse appears in the activation signal sent from the inhibit gate 14, the leading edge detection circuit 15 generates a pulse having a predetermined time width that rises at the rising edge of the pulse of the activation signal, and sets the flip-flop 16. Then, a pulse is caused to rise on the signal d. When a pulse rises on the signal d, the oscillation circuit 17 starts generating a clock signal having a predetermined period and sends this to the counter 18 as the signal e. Counter 18 counts the clock signals and generates a pulse to reset flip-flop 16 when a predetermined number m is reached. flipflop 16
When the signal d is reset and the pulse of the signal d falls, the oscillation circuit 17 stops generating the clock signal, and the pulse of the signal h, which is an inversion of the signal d, rises and resets the count value of the counter 18 to zero. During this period, a predetermined number m of clock signals appear on the signal e. Among the signals generated by the control circuit 7 upon receiving the signal a, signals b and c are sent in parallel to the message assembly circuit 5 as selection signals or signals e and h as control signals, and signals f and i are sent as selection signals. The signal is sent in parallel to the switching circuit 8 together with a signal g including a command signal and a start signal.

In FIG. 1, in order to avoid cluttering the drawing and making it difficult to read, locations where a plurality of signals are sent in parallel are shown by a single signal line. The switching circuit 8 connects the signal g to the relay end 10 (or 11) and sends the signal g to the meter sensor connected to the relay end 10 (or 11) only while the signal f (or i) is H. It is connected to the input/output circuit 6 through serial telegram signals sent from the relay terminal 10 (or 11).

5 is a block diagram showing an example of the structure of the message assembly circuit 5 in the meter sensor 1 shown in FIG. 5 and FIG. 1. FIG.
In the message assembly circuit 5, the integration signal sent from the counter 4 and the additional signal sent from the signal generation circuit 25 are applied in parallel to the gate circuit 24 so as to constitute a message signal in a predetermined format. Further, a parallel telegram signal in a predetermined format, which is sent from the signal generating circuit 25 and indicates the start of the relay end connection, is applied to the gate circuit 23. The gate circuits 24 and 23 receive selection signals, that is, signals b and c, respectively, from the control circuit 7, and when the signal b (or c) becomes H, the parallel telegram signal applied to the gate circuit 24 (or 23) is output. It is connected to the parallel-serial conversion circuit 26 and applied. The parallel-serial conversion circuit 26 is connected to the control circuit 7
It receives control signals, that is, signals h and e from It is sent to the input/output circuit 6. The number m of clock signals of the signal e is set equal to the length (number of bits) of the telegram signal of a predetermined format. Note that in the signal a shown in FIG. 4, when the command signal D3 indicating a request to send a message signal including an integration signal appears after the command signal D2 indicating a request for relay end connection, the command signal D3 is read after the command signal D3. Since the starting signal at the rising edge of the pulse is inhibited by the inhibition gate 14 in the circuit shown in FIG. Not sent.

As described in detail above, the meter sensor 1 shown in FIG. 2 sends out a telegram signal containing an integration signal generated within the meter sensor 1, or By connecting one of the relay ends 10 and 11 to a communication line, it is possible to interrupt and send out a telegram signal containing the integrated signal of the meter sensor connected to the relay end 10. The meter sensor 1 in Fig. 2 is
Although two relay ends 10 and 11 are provided, it is clear that the number of relay ends may be one or three or more.

As is clear from the above explanation, the present invention allows a desired meter sensor to be connected to one communication line without requiring any additional equipment or significantly increasing the specifications. This has the effect of realizing a meter sensor that can selectively send and receive signals.

[Brief explanation of drawings]

Fig. 1 is a block diagram showing the case where multiple conventional meter sensors are connected to one communication line, Fig. 2,
3 and 5 are block diagrams showing one embodiment of the present invention, and FIG. 4 is a time chart illustrating the operation of the circuit shown in FIG. 3. 1...Meter sensor, 2...Meter, 4...Counter, 5...Telegram assembly circuit, 6...Input/output circuit, 7...Control circuit, 8...Switching circuit, 9...
Input/output end, 10, 11...relay end.

Claims (1)

[Claims] 1 an integrating means that receives a pulse signal indicating a flow rate measurement value given from a meter, counts the pulse signal, and sends an integrated signal indicating an integrated flow value; a signal generating means for sending out a response signal including one; a switching means having at least one terminal for connecting an external meter sensor; and a switching means for selecting any one of the terminals and switching the connection; and an external device. input/output means for generating a control signal in response to an operation request signal given from the switching means and transmitting a response signal sent from the signal generating means and the terminal to the external device; At most one external meter sensor is connected to the terminal, and when the control signal requests the sending of the answer signal from the signal generating means, the answer signal is sent to the input/output means, and the control signal is sent to the input/output means. requests switching of the connection of any one of the external meter sensors, the connection between the external meter sensor and the input/output means is switched by switching the connection of the terminal of the switching means, and the external meter sensor is switched. A meter sensor, wherein the input signal is transferred to the external meter sensor while the meter sensor is connected, and a response signal from the meter sensor is sent to the input/output means.