JPH035986Y2 - - Google Patents

Description

[Detailed description of the invention] [Technical field] The present invention receives a contact output such as a relay contact output or a switch output of a sensor, and operates to transmit a change detection signal when this contact input changes. The present invention relates to a wireless data transmitter.

[Background technology]

In general, contact outputs such as relay contact outputs of sensors such as fire detection sensors, gas detection sensors, and security sensors, and switch outputs such as emergency switches and call switches are input, and are activated when this contact input changes. This type of wireless data transmitter equipped with a transmission circuit that transmits a change detection signal includes an input circuit that receives contact input from a sensor, etc., a latch circuit that latches a signal from the input circuit when a latch clock is input.
A comparator circuit that compares the input signal and the output of the latch circuit and outputs an input change signal when they do not match, and a delay function by charging the capacitor that constitutes the time constant circuit. It is composed of a delay circuit, etc., which delays the input signal to form a latch clock, and triggers a monostable multivibrator, which sets the operating time of the transmitting circuit, based on the input change signal. In such a conventional example, if an input change occurs and the monostable multivibrator is triggered, and another input change (for example, noise, etc.) occurs before the signal is transmitted from the transmitting circuit, this input change causes the monostable multivibrator to latch. There was a problem in that the circuit was inverted again and instead of transmitting the signal of the first input change, the signal of the second input change was transmitted, causing the first data to be lost.

[Purpose of invention]

The present invention has been proposed in view of the above-mentioned points, and it is an object of the present invention to provide a wireless data transmitter that is highly noise resistant and does not cause empty data transmission.

[Disclosure of invention]

FIG. 1 shows a specific circuit diagram of an embodiment of the present invention. To explain the configuration of the transmitting means, the state of contact 1 such as a sensor output contact or a switch output is converted into a voltage signal and the input signal V ₁ , a latch circuit 3 that latches the input signal V ₁ when the latch clock V ₅ is input, and a latch circuit 3 that compares the input signal V ₁ and the output ₃ of the latch circuit 3 and outputs the input signal when they do not match. A comparator circuit 4 consisting of an exclusive OR circuit that outputs a change signal _V4 , a delay circuit 5 that delays the input change signal _V4 to form a latch clock _V5 , and a transmitter circuit triggered by the input change signal _V4 . The power supply is controlled by the monostable multivibrator 6 which sets the operation time of the 8, and the output V ₆ of the monostable multivibrator 6 via the transistor Q ₃ and the 3-terminal regulator 8c, and when the power is supplied, the latch circuit 3 output V ₃ , ₃ , and a transmitting circuit 8 that transmits a change detection signal _V8 based on V8. The transmitting circuit 8 is composed of a transmission signal forming circuit 8a and a modulating circuit 8b made of an LSI.

FIG. 4 is a time chart showing the operation of the transmission signal forming circuit (MN6026) 8a. After a predetermined reset time To has elapsed from the time the power was turned on,
Scan pulses S ₁ to _{S 6} are sequentially output at fixed time intervals T ₁ , and in synchronization with S ₆ of these, the outputs V ₃ and ₃ of the latch circuit 3 are read as scan inputs via transistors Q ₁ and Q ₂ . It's starting to become easier. Here, the change detection signal _V8 is as shown in FIG.
This is an FSK signal that transmits data by modulating a carrier wave (260MHz) with a data signal Vd that combines four types of frequencies ₁ to ₄ in time series, and in the example, 4 bits B to prevent interference. ₂ to _B5 house code and type of output contact 1 (fire detection,
6-bit data consisting of 2-bit _B1 and _B6 data codes indicating the contact state (on, off, etc.) and the contact state (on, off) is transmitted, and the change detection signal _V8 is continuously transmitted. In the case of transmission, a no-signal period corresponding to 2 bits is provided between the signals _V8 . In addition, the switch AD connected to the scan terminal of the transmission signal forming circuit 8a is for address setting.
UN is for setting the unit number, and switch TP is for setting the type. Furthermore, the three-terminal regulator 8c outputs V ₆ to the monostable multivibrator 6.
This is a constant voltage circuit whose power supply is controlled by transistor _Q3 driven by Q3.

Next, the output of the OR circuit 15 that ORs the scan pulses of the transmission signal forming circuit 8a of the transmitting circuit 8 and the output of the delay circuit 5 are logically operated, and the clock pulse _V5 is sent to the latch circuit 3 using the output. and,
The retransmission means 9 that detects the end of transmission of the change detection signal V ₈ by triggering the monostable multivibrator 6 and operates the comparison circuit 4 again will be described. OR circuit 15 consists of four transistors Q ₄
The base of each transistor _Q4 to _Q7 is connected to the scan terminal _of the transmission signal forming circuit 8a via a resistor and switch AD, and the collector is OR-connected as an open collector.
The output end of the commonly connected OR circuit 15 is connected to one input end of the NAND gate 16. The delay circuit 5 described above also includes resistors R ₁ , R ₂ , a diode D ₁ ,
A delay circuit 5 is provided between the output terminal of the NAND gate ₁₇ provided on the output side of the comparator circuit 4 and the other input terminal of the NAND gate 16. Here, the charging time constant τa of capacitor C ₁ is composed of capacitor C ₁ , resistor R ₁ and diode D ₁ , and
The discharge time constant τb of C ₁ is composed of a capacitor C ₁ and a resistor R ₂ , and the relationship between the resistors R ₁ and R ₂ is set as R ₁ <R ₂ . In addition, this discharge time constant τb (NAND gate 16
Transistor Q ₃ for supplying power to the transmission signal forming circuit 8a
It is set longer than the time τc from when the transmission signal forming circuit 8a turns on until the scan pulse is output from the transmission signal forming circuit 8a (FIG. 2d) (τb>τc). here,
τa is the dead time for input changes in the input circuit 2 (the time during which it is not determined that there is an input change), and by setting τb > τc, the noise resistance from the input terminal of the input circuit 2 is improved and input chattering is removed. This will be discussed later. Note that due to the relationship between the above resistances R ₁ and R ₂ , R ₁
It is not necessary that <R ₂ . Then, upon receiving the output of the delay circuit 5, the output of the NAND gate 16 is used to trigger the monostable multivibrator 6, and the latch clock _V5 to the latch circuit 3 is used.
It is said that When the monostable multivibrator 6 is triggered, the output terminal Q becomes H, turning on the transistor _Q8 and lighting the light emitting diode 18.
Displays that it is being sent. In addition, when the battery voltage is detected by the comparison detection circuit 19 and the battery voltage becomes low, the unstable multi-function device 21 is
is driven, transistor _Q9 is turned on, and light emitting diode 18 blinks.

The operation will be specifically explained below. In addition, A to J in Figures 2 and 3 are A to J in Figure 1.
This shows the waveform of a point. Now, latch circuit 3
When output ₃ is at H level as shown in Figure 2b, output contact 1 is turned on and input signal _V1 output from input circuit 2 is at H level as shown in Figure 2a. Then, the input signal _V1 input to the comparator circuit 4 and the output V3 of the latch circuit ₃ match, and the input change signal output from the comparator circuit 4
_V4 becomes L level, this L level signal is inverted by NAND gate 17 and becomes H level, and capacitor _O1 of delay circuit 5 is charged with time constant τa as shown in Fig. 2c. . Since the output of the OR circuit 15 connected to one input terminal of the NAND gate 16 is at H level, the output of the NAND gate 16 becomes H level as shown in FIG. 2e when the potential of the capacitor _C1 rises. Inverts from level to L level. Therefore, the triggered monostable multivibrator 6 as shown in FIG.
The output terminal of Q3 becomes L level, and the transistor _Q3
is turned on to drive the three-terminal regulator 8c and supply power to the transmission signal forming circuit 8a.

On the other hand, in the delay circuit 5, this input change signal V ₄
is delayed by a certain period of time to form a latch clock _V5 through the NAND gate 16, and the input signal _V1 is latched into the latch circuit 3 by the latch clock _V5 , and the output terminal of the latch circuit 3 is connected to the output terminal shown in FIG.
It is set to L level as shown in FIG. Therefore,
The comparator circuit 4 detects a mismatch and outputs an H level, and the output of the NAND gate 17 becomes an L level, so the capacitor _C1 of the delay circuit 5 is discharged as shown in Figure 2c with a discharge time constant τb. . By the way, power is supplied to the transmitting circuit 8 for a preset period of time by the output V ₆ of the monostable multivibrator 6, and the transmitting circuit 8 is activated. The pulse width of the power supply control pulse is the change detection signal.
The time required for transmission is set slightly longer than that of _V8 . Here, the transmission signal forming circuit 8a of the transmitting circuit 8
forms a transmission signal based on the output V ₃ , ₃ of the latch circuit 3 at a predetermined timing as described above, and the modulation circuit 8b modulates the carrier wave with this transmission signal and transmits the change detection signal V ₈ .

Here, since the scan signal is output after a predetermined time τc has elapsed since power is supplied to the transmission signal forming circuit 8a, the output of the OR circuit 15 becomes L level as shown in FIG. 2d, and the NAND gate 16 Set the output to H level. However, if the contact 1 changes from the on state to the off state as shown in FIG. 2a within the time required for transmitting the change detection signal, the retransmission means 9
transmits an off-state signal by That is,
If the contact 1 changes from the on state to the off state while transmitting the change detection signal, the output of the input circuit 2 becomes the L level, which coincides with the L level of the output terminal of the latch circuit 3. , comparison circuit 4
outputs an L level, inverts the output of the NAND gate 16, and starts charging the capacitor _C1 again as shown in FIG. 2c. And this capacitor C ₁
One input terminal of the NAND gate 16 is held at H level even when the charging potential is . On the other hand, when the transmission signal forming circuit 8a finishes transmitting the change detection signal _V8 based on a series of formats, the output of the OR circuit 15 becomes H level, so the output of the NAND gate 16 becomes L level as shown in FIG. 2e. Reverse the level and trigger the monostable multivibrator 6 again,
As shown in FIG. 2g, a change detection signal _V8 indicating that contact 1 is in the OFF state is transmitted.

Here, the discharge time constant τb, which is the gist of the present invention, is
After the transistor _Q3 for supplying power to the transmission signal forming circuit 8a is turned on, the transmission signal forming circuit 8a
The time from when the scan pulse is output (d in Figure 2) is set longer than τc (τb > τc).
Let's talk about that. In other words, if the discharge time τb is shorter than τc, there is a change in the input of contact 1,
Until the monostable multivibrator 6 is triggered and the scan pulse of the transmission signal forming circuit 8a is output (for example, the reset terminal of the transmission signal forming circuit 8a rises) (transistors Q ₄ to _{Q 7} )
If the input changes again, the first ON data will be lost. In other words, contact 1 is turned on and capacitor C ₁ is charged as described above, and NAND gate 16 is inverted to trigger monostable multivibrator 6 and latch circuit 3, but from this point on, the transmission signal forming circuit 8a starts scanning. Before the pulse is output, when the contact 1 turns off, the capacitor C ₁ is quickly discharged due to the discharge time constant τb of the capacitor C ₁ , and this change in the contact 1 is output to the latch circuit 3 by the output of the NAND gate 16 . Flip again. Therefore, since the transmission signal forming circuit 8a is controlled by the output of the latch circuit 3, the latch circuit 3
Due to the inverted OFF data, the transmission circuit 8 transmits the OFF data change detection signal _V8 , and the first ON data is lost. Therefore, the discharge time constant τb of capacitor _C1 is
After the transistor _Q3 for supplying power to the transmission signal forming circuit 8a is turned on, the transmission signal forming circuit 8a
By setting the time from τ to the output of the scan pulse (Fig. 2 d) longer than τc, in other words,
At the level of the input terminal of the NAND gate 16, H
By making the time τb longer than τc to reach the threshold at which the output inverts when the level drops from the L level to the L level, input changes that occur within the time τc, such as noise, are not accepted, and noise resistance is improved. This is to improve or eliminate input chatter.

Note that the change detection signal _V8 emitted from the wireless data transmitter is received by a wireless data receiver (not shown), and the wireless data receiver checks whether the house codes _B2 to _B5 match,
If they match, the load corresponding to the output contact 1 is controlled based on the data codes B ₁ to _{B 6} (blinking of an indicator light, generation of an alarm sound by a speaker, etc.).

By the way, the wireless data transmitter used in this embodiment can be turned on or off by setting the on or off switch 10 in advance when the input changes to the on or off state. A repeating transmitting means 12 is provided for repeatedly transmitting a change detection signal. Repeated transmission means 1
2 is a changeover switch 10 that selects whether to send priority to ON or OFF of sensor contact 1;
and a repeat transmitter circuit 11 that causes the transmitter circuit ₈ to intermittently repeatedly transmit a change detection signal V8 indicating the state when the contact 1 output becomes a priority state, and the repeat transmitter circuit 11
is composed of an exclusive OR circuit 11a, a D flip-flop 11b, and a monostable multivibrator 11c. The exclusive OR circuit 11a receives the signal from the changeover switch 10 and the change signal of the contact 1 from the input circuit 2, and
It is input to the D terminal of the D flip-flop 711.

Next, the operation of the repeat transmission means 12 will be explained. Now, when the changeover switch 10 is set to the side (b side) where turning on the output of contact 1 is given priority, when contact 1 which is off is turned on, the above-mentioned normal operation is resumed as soon as the state changes. Therefore, the change detection signal V ₈ is transmitted from the transmitting circuit 8 . At this time, the D flip-flop 11b is reset by the input circuit 2, and the monostable multivibrator 11c is triggered as shown in FIG. 3b. Here, after the transmission of the on-state change detection signal _V8 is completed as shown in FIG. 3c, the output of contact 1 is maintained for a predetermined time set in the time constant circuit of the monostable multivibrator 11c as shown in FIG. 3d. continues to be on, the output of the exclusive OR circuit 11a becomes H level at the rising edge of the output of the monostable multivibrator 11c after the elapse of the required transmission time (Fig. 3e), and the D of the D flip-flop 11b becomes high. The terminal becomes H level, and the output of the D flip _- flop 11b is inverted to L level as shown in FIG.
Therefore, the normal operation is repeated and the change detection signal V ₈ is transmitted again from the transmission circuit 8, and while the contact 1 is in the on state, the change detection signal V ₈ is repeatedly transmitted at fixed time intervals. It turns out. on the other hand,
When contact 1 turns off (Fig. 3a), a change detection signal _V8 indicating that contact 1 output is turned off is transmitted by normal operation at the time it turns off, but exclusive OR circuit 11a Since the output of V8 is at L level, the change detection signal _V8 is not repeatedly transmitted. In addition, the changeover switch 10
is set to the side (b side) in which ON of the contact 1 output is prioritized, the change detection signal _V8 is intermittently and repeatedly transmitted from the transmitting circuit 8 while the contact 1 is in the ON state. and when the state is off, a change detection signal is generated only at the time of change.
Only _V8 is sent.

[Effect of idea]

As described above, the present invention is a wireless data transmitter that receives a contact output such as a sensor's relay contact output or switch output, and operates when the contact input changes to transmit a change detection signal. , scan pulses are sequentially output from the control output terminal at regular intervals for a predetermined period of time after the power is turned on, and the scan pulses are arbitrarily input to the control input terminal to combine the signals in a predetermined time series. A transmitter circuit that outputs a detection signal, an input circuit that converts contact input into a voltage signal to form an input signal, a latch circuit that latches the input signal when a latch clock is input, and a circuit that outputs the input signal and latch circuit output. A comparator circuit that compares the signals and outputs an input change signal when they do not match, and a delay function by charging the capacitor that makes up the time constant circuit.The delay function delays the input change signal to form a latch clock. At the same time, a delay circuit that triggers a monostable multivibrator that sets the operating time of the transmitting circuit based on an input change signal forms a transmitting means, and a capacitor of the delay circuit is discharged by the latch output of the latch circuit. Since the voltage time constant is set to be longer than the time from when the power is turned on to the transmitter circuit until the scan pulse is output, the capacitor in the delay circuit is discharged until the change detection signal is transmitted from the transmitter circuit. Because the time constant is long, the output of the delay circuit will not be reversed even if the input changes due to noise, etc. Therefore, unlike conventional methods, wireless data transmission with high noise resistance and no empty data transmission is possible. This has the advantage of being able to provide a large number of machines.

[Brief explanation of drawings]

FIG. 1 is a specific circuit diagram of an embodiment of the present invention, FIGS. 2 and 3 are explanatory diagrams of the same operation, and FIGS. 4 and 5 are operation waveform diagrams of the same. 1 is an output contact, 2 is an input circuit, 3 is a latch circuit, 8 is a comparison circuit, 5 is a delay circuit, 6 is a monostable multivibrator, and 8 is a transmitter circuit.

Claims (1)

[Scope of utility model registration request] In a wireless data transmitter that receives a contact output such as a sensor's relay contact output or switch output, and is configured to operate and transmit a change detection signal when this contact input changes, power is turned on from the control output terminal. A transmitting circuit that sequentially outputs scan pulses at regular intervals for a predetermined period of time, inputs the scan pulses to a control input terminal arbitrarily, and outputs a change detection signal configured by combining the signals in a predetermined time series; , an input circuit that converts a contact input into a voltage signal to form an input signal, a latch circuit that latches the input signal when a latch clock is input, and a latch circuit that compares the input signal and the output of the latch circuit to detect a mismatch. A comparator circuit that outputs an input change signal and a delay function are provided by charging the capacitors that make up the time constant circuit.The delay function delays the input change signal to form a latch clock, and also changes the operating time of the transmitter circuit. forming a transmitting means with a delay circuit that triggers a monostable multivibrator based on an input change signal;
A wireless data transmitter characterized in that the discharge time constant of the capacitor of the delay circuit that is discharged by the latch output of the latch circuit is set to be longer than the time from when the transmitter circuit is powered on until the scan pulse is output.