JPS6239509Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a meter reading terminal device and a reading correction device that store measured values of a meter such as a power meter.

When attaching a meter reading terminal to a meter, it is necessary to match the stored value of the encoder inside the meter reading terminal to the measured value of the meter. For this purpose, the readout corrector is connected to the meter reading terminal and the stored value of the encoder is first read out. A separate signal line was required because a synchronization pulse was used which was carried by a separate signal line.

The object of the invention is to provide a meter reading terminal and readout corrector that does not require a separate signal line for synchronization.

An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram of the meter reading terminal, and FIG. 2 is a block diagram of the reading corrector. In addition, in the meter reading terminal, the circuit until the pulse from the watt-hour meter with transmitter is input to the encoder 1, the receiving circuit and the transmitting circuit that transmit the measured value of the encoder 1 in response to a command from the center are the same as the present invention. It is omitted because it is not directly related.

When reading out the weighing value stored in the encoder 1, operate the operation circuit 2 of the readout corrector to cause the keycode generation circuit 3 to generate a readout keycode (for example, a 4KHz continuous waveform signal).
It is converted into an optical signal by the key code interface 4 and sent to the key code interface 5 of the meter reading terminal which is photoelectrically connected. The readout keycode converted back into an electrical signal by the keycode interface 5 is input to the discrimination circuit 6, and when the discrimination circuit 6 discriminates the input of the readout keycode,
Open the read gate circuit 7. The encoder 1 always outputs the stored measured values to the parallel-to-serial conversion circuit 8.
Since the meter always converts the measured weight value into a read data signal consisting of serial pulses, when the read gate circuit 7 opens, the read data signal is converted into an optical signal by the read interface 9, and the read data signal is read out. Sent to corrector.

The read data signal consists of a digit designation pulse 10 located at the 4 digit designation bits and a data pulse 11 located at the 4 data bits arranged in series for each digit, as shown in FIG. 3A or B. FIG. 3A shows the case where the numerical value in the 10 ³ digit is "9", and FIG. 3 B shows the case where the numerical value in the 10 ¹ digit is "6". The read data signal is
The numbers are arranged from the 10 ³ digit to the 10 ⁰ digit, with 12 spaces between the digits, and when the 10 ⁰ digit is finished, it returns to the 10 ³ digit and repeats. This is the maximum digit to identify the start position of the read data signal.
The digit designation pulse 13 for the 10 ³ digit is shaped into half the pulse width of the other digit designation pulses 10 and data pulses 11. Encoder 1 as shown in FIG.
A half-bit circuit 14 is connected to the 10 ³ digit digit designation pulse output terminal, and the 10 ³ digit digit designation pulse is shaped into a half-bit pulse width by the half-bit circuit 14 .

The read data signal is converted back into an electrical signal by the read interface 15 of the read corrector, and the start position detection circuit 16 detects the start position of the read data signal, that is, the 10 ³ digit designation pulse 13. Using this start position as a reference, the serial-parallel conversion circuit 17 inversely converts the read data signal into a measured value, and the display circuit 18 displays the measured value. An example of the start position detection circuit 16 is shown in FIG. The pulse Pi output from the readout interface 15 is input to the RS flip-flop _FF1 and the D flip-flop _FF2 . Since the RS flip-flop _FF1 makes the output of the terminal 0 at the rising edge of the pulse Pi, the reset of the counter CTR is released. Counter CTR is a NOR circuit
Start counting the clock pulses Pc input via NOR. When the count value of the counter CTR reaches Qn, 1 is output from the Qn terminal to the C terminal of the D flip-flop FF _2. If the input to the D terminal of the D flip-flop at that time is 1, 0 is output from the terminal.
If it is 0, it outputs 1, respectively. Count value Qn
is set between half the time of one bit and the time of one bit. Therefore, if the pulse width of pulse Pi is half bit as shown in Fig. 5, D when 1 is output from the Qn terminal of counter CTR.
The input to the D terminal of flip-flop _FF2 is always 0, so 1 is output from the terminal. If the pulse width of the pulse Pi is 1 bit, the input to the D terminal of the D flip-flop FF ₂ will be 1 when 1 is output from the Qn terminal of the counter CTR, and
The output of the terminal is 0. When the count value Q'n of the counter CTR is reached, the output from the Q'n terminal is applied to the S terminal of the D flip-flop _FF2 , and the output of the terminal is returned to zero. Therefore, a synchronizing pulse Ps is formed on the output side of the terminal, and this synchronizing pulse Ps is sent to the serial-parallel conversion circuit 17 as a start position detection signal of the read data signal. counter
Since the output from the Q'n terminal of CTR simultaneously resets the RS flip-flop _FF1 , the output of that terminal becomes 1 and the counter CTR is also reset.

When correcting the measured value of the encoder 1, the operating circuit 2 is operated to set a corrected value. This modified value is displayed on the display circuit 18. When the key code generation circuit 3 generates a correction key code (for example, an 8KHz continuous waveform signal), it is sent to the discrimination circuit 6 via the key code interfaces 4 and 5.
The determination circuit 6 opens the modification gate circuit 19 by determining the input of the modification key code. As a result, the modified data signal generated by the modified data generation circuit 20 is transferred to the modified data signal generated by the modified data generating circuit 20
22 and the write circuit 2 via the correction gate circuit 19.
3 and is sent to the encoder 1 by the write circuit 23.
The corrected value is written to. Note that since the modified data signal is sent only once and not repeatedly, no synchronization pulse is required.

In the present invention, the meter reading terminal is equipped with a half-bit circuit that shapes only the pulse width of the digit designation pulse for the largest digit of the measured value to half the pulse width of the other digit designation pulses and data pulses, and the readout corrector is equipped with
Since we have provided a start position detection circuit that detects the start position of the read data signal by detecting a pulse with half the pulse width, the start position of the read data signal repeatedly sent from the meter reading terminal to the read corrector can be adjusted for synchronization. can be easily detected without the need for a separate signal line.

[Brief explanation of the drawing]

Fig. 1 is a block diagram of a meter reading terminal according to an embodiment of the present invention, Fig. 2 is a block diagram of a read corrector according to an embodiment of the present invention, and Figs. 3 A and B show part of the read data signal. FIG. 4 is a circuit diagram of an example of a start position detection circuit, and FIG. 5 is a diagram showing waveforms of each part thereof. 1...Encoder, 3...Key code generation circuit, 8...Parallel-serial conversion circuit, 10...
Digit designation pulse, 11...Data pulse, 13...
Maximum digit designation pulse, 14...Half bit circuit, 16...Start position detection circuit, 17...Serial to parallel conversion circuit, 18...Display circuit.

Claims (1)

[Scope of utility model registration request] A meter reading device that converts the measured value stored in the encoder when receiving a readout key code from a readout corrector into a readout data signal consisting of a digit designation pulse and a data pulse that follows the pulse in series for each digit, and outputs the signal. In the terminal device and the readout correction device that receives the readout data signal, converts it back to a weighing value, and displays it on the display circuit, the meter reading terminal transmits only the pulse width of the specified pulse for the largest digit of the weighing value to other digits. A half-bit circuit is provided to shape the designated pulse and data pulse to half the pulse width, and the read corrector is provided with a start position detection circuit that detects the start position of the read data signal by detecting a pulse with half the pulse width. A meter reading terminal device and a reading correction device characterized by the following.