JPH071863Y2 - Timer device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of use] The present invention relates to a timer device which is driven by a power supply whose voltage is lowered by a step-down impedance and which operates an output relay in a timed circuit.

[Conventional technology]

A timer device shown in FIG. 5 is known as a timer device driven by stepping down a relatively high power supply voltage with a step-down impedance. Here, the time limit circuit 1 is connected so as to supply power from the DC power supply 2 through the switch 3 and the DC circuit of the two step-down resistors 4 and 5. The output relay 6 is connected in series with the collector and emitter of the output transistor 7, and both step-down resistors 4,
It is connected to the connection point of 5 and the negative side of the power supply 2, and the base of this transistor 7 is connected to the output terminal of the time-limit circuit 1.

When the switch 3 is turned on, the time limit circuit 1 is started to start timing, and after a predetermined time, the time limit circuit 1 times up and outputs a signal, and the transistor 7 is turned on, so that the output relay 6 operates.

[Problems to be solved by the device]

In this timer device, a DC power supply 2 having a relatively high voltage is stepped down by both step-down resistors 4 and 5 and applied to a time circuit 1 to drive it. For this reason, the voltage fluctuation rate is high, and when the time limit circuit 1 times up and the transistor 7 is turned on and an exciting current flows through the coil of the output relay 6, the voltage drop in the resistor 4 increases and a sufficient current flows through the time limit circuit 1. However, there is a problem in that the operation of the time limit circuit 1 becomes unstable. In order to stabilize the operation of the time limit circuit 1, a resistor 5
Although it is possible to reduce the resistance value of the resistor and supply a sufficient current to the time circuit 1, the current flowing through the resistor 4 becomes large, and the heat generated by the resistor 4 deteriorates the electronic components constituting the timer device. However, there is a problem in that the reliability of the timer device is impaired.

An object of the present invention is to provide a reliable timer device that supplies stable current to a time circuit regardless of whether or not the time circuit is timed up, consumes less current, and has less thermal deterioration of electronic components. is there.

[Means for Solving the Problems]

In order to solve the above-mentioned problems, the present invention comprises a time circuit for measuring time, an output transistor that turns on or off at the output of this time circuit, and an output relay that operates when this output transistor turns on or off. In the timer device driven via
The output relay is connected in series with the time circuit, and a parallel resistor having a resistance value substantially the same as that of the output relay is provided, and a collector and an emitter are connected in series with the first relay and a collector. A switching means including a second transistor whose emitter is connected in series to the parallel resistance is provided, and the series circuit of the first transistor and the output relay is connected in parallel to the series circuit of the second transistor and the parallel resistance. The first transistor of the switching means is on / off controlled according to the on / off state of the output transistor, and the second transistor of the switching means is a base current flowing through the output relay when the first transistor is off. Is controlled to be turned on by the switch and is turned on when the first transistor is turned on. Is controlled, the switching means is characterized in that switching connected in series to the timing circuit and an output relay and the parallel resistor according to the on and off of the output transistor.

[Action]

In the timer device according to the present invention, when the output transistor is turned off during the time measurement of the timed circuit, the first transistor forming the switching means is turned off and the second transistor is turned on during the time measurement of the timed circuit. Yes,
As a result, the output relay is disconnected, and the power supply voltage is supplied to the time circuit through the parallel resistance. When the time circuit is up, the first transistor forming the switching means is turned on and the second transistor is turned off. The parallel resistance is disconnected and the power supply voltage is supplied to the time circuit via the output relay. Also, if the output transistor is turned on while the time circuit is timing, the power supply voltage is supplied to the time circuit via the output relay by the switching means while the time circuit is timing. The power supply voltage may be supplied to the timed circuit through the parallel resistor, but in any case, the timed circuit is timed up by switching and connecting the parallel resistor and the output relay in series with the timed circuit by the switching means. Stable power is supplied to the timed circuit regardless of whether or not to do so.

〔Example〕

First, a circuit diagram of a timer device previously filed by the present applicant will be described with reference to FIGS. 1 and 2. 1 and 2, the same elements as those in FIG. 5 are designated by the same reference numerals as those in FIG. In FIG. 1, the time limit circuit 1 includes a DC power source 2, a switch 3 and a step-down resistor 4 when the time is up.
Is connected so as to supply power through a series circuit of a step-down circuit including the above, a collector / emitter of the transistor 8 and the output relay 6. The base of the transistor 8 is connected to the collector via the resistor 9. The transistor 10 has a collector connected to the base of the transistor 8, an emitter connected to a connection point between the output relay 6 and the timing circuit 1, and a base connected to the collector of the transistor 8 via the resistor 11. The collector of the output transistor 7 is connected to the base of the transistor 10, the emitter is connected to the negative terminal of the power supply 2, and the base is connected to the output terminal of the timing circuit 1. The resistance value of the resistor 9 is set equal to the resistance value of the coil of the relay 6, and the resistance 11 is set to be a resistance value of the resistance 9 times the current amplification factor of the transistor 10.

When the switch 3 is turned on, the signal of the time circuit 1 is at a low level and the transistor 7 is off.
A base current flows through the resistor 11 to the transistor 10
Turns on. When the transistor 10 is on, the transistor 8 has a base / emitter transistor 10 and a relay 6
It will be short-circuited with so keep it off. Therefore, the time-limit circuit 1 is supplied with power from the power supply 2 through the switch 3, the resistor 4, the resistor 9 and the transistor 10, and the time-limit circuit 1 is started to start timing. Since a transistor having a sufficiently large current amplification factor is selected for the transistor 10, the resistance value of the resistance value of the resistance value of the resistance value of the resistance value of the resistance value of the resistance value of the resistance value of the transistor 10 is approximately doubled.
11 is a sufficiently high resistance value, and this current can be ignored. Therefore, the current consumption of the timer device at this time is determined by the voltage of the power supply 2, the resistance values of the resistors 4 and 9 and the equivalent resistance value of the time-limit circuit 1.

When the time limit circuit 1 times up after a predetermined time, the transistor 7 turns on, the base current of the transistor 10 is short-circuited, the transistor 10 turns off, the base current flows to the transistor 8 through the resistor 9, and the transistor 8 turns on. Turn on. When the transistor 8 is turned on, power is supplied to the time circuit 1 from the DC power supply 2 via the switch 3, the resistor 4, the transistor 8 and the relay 6, and the relay 6 operates. The current consumption of the timer device at this time is determined by the resistance values of the resistor 4, the relay 6 and the equivalent resistance value of the time circuit 1, and the resistance value of the resistor 9 is made equal to the resistance value of the coil of the relay 6. The current value of the timer device when the time is measured by the time limit circuit 1 and when the time is up becomes substantially equal, and the timer device operates stably. Moreover, since the same current flows in series through the relay 6 and the time limit circuit 1, the current consumption of the timer device is reduced as compared with the conventional example. In this embodiment, the relay 6
Although the current has been described assuming that the current of the time circuit 1 and the current of the time circuit 1 have the same value, in general, the current of the time circuit 1 is often lower than the coil current of the relay 6. In such a case, a bypass circuit may be provided in parallel with the time limit circuit 1 so that the sum of the current value of the relay 6 and the current value of the time limit circuit 1 and the bypass circuit becomes equal.

FIG. 2 shows a modification different from FIG. This modified example is different from FIG. 1 in that the power source is the AC power source 2a, and accordingly, the rectifier circuit 13 and the smoothing circuit 14 are provided immediately after the step-down resistor 4.
Is added, and it is used as an AC timer device. The other connections and operations are the same as those in FIG. 1, and therefore their explanations are omitted.

FIG. 3 is a connection diagram of a timer device showing an embodiment of the present invention. The difference between the embodiment shown in FIG. 3 and the circuit diagram of FIGS. 1 and 2 is that FIGS. The transistors 8 and 10 which are the switching means 12 of the output relay 6 of NPN are NPN.
In contrast to the transistors, the switching means 12 of the output relay 6 in FIG. 3 uses PNP transistors 8 and 10 respectively, which is a difference from FIGS. 1 and 2. In FIG. 3, transistors 8 and 10 are the first and second transistors, respectively, which constitute the switching means 12 of the present invention. That is, in FIG. 3, the time limit circuit 1 is connected so as to supply power from the DC power source 2 through the series circuit of the switch 3, the step-down resistor 4, the emitter / collector of the PNP transistor 8 and the output relay 6 when the time is up. . The series circuit of the emitter / collector of the transistor 8 and the output relay 6 is connected in parallel with the series circuit of the emitter / collector of the transistor 10 and the parallel resistor 9. The resistance value of the parallel resistor 9 is made substantially equal to the resistance value of the coil of the relay 6. The base of the transistor 10 is connected to the collector of the transistor 8 and the connection point of the output relay 6 via the resistor 15. Further, the base of the transistor 8 is connected to the negative side of the DC power source via the resistor 16 and the collector / emitter of the output transistor 7.

When the switch 3 is turned on, the signal of the timing circuit 1 is at a low level and the transistor 7 is off.
No base current flows through the transistor 8 and the transistor 8 is off. However, since a base current flows through the transistor 10 via its emitter, the resistor 15 and the output relay 6, the transistor 10 is turned on. Therefore, the time circuit 1 is supplied with power from the power supply 2 through the switch 3, the resistor 4, the transistor 10 and the resistor 9. At this time, since the transistor 10 having a sufficiently large current amplification factor is selected, the base current of the transistor 10 is extremely small and the relay 6 does not operate. When the time limit circuit 1 times out after a predetermined time, the transistor 7 is turned on, the transistor 8 is also turned on, the transistor 10 is turned off, the parallel resistor 9 is disconnected, the relay 6 is energized, and the relay 6 operates. Since the resistance values of the parallel resistor 9 and the relay 6 are made substantially equal, the time circuit 1
The current flowing into the timer circuit 1 is almost the same during the time counting circuit 1 and after the time is up.

FIG. 4 shows an embodiment different from FIG. This embodiment differs from the others in that only transistor 8 is a PNP transistor. That is, the time limit circuit 1 is connected so as to supply power via the power supply 2, the switch 3, the resistor 4, the relay 6 and the emitter / collector of the transistor 8 when the time is up. A series circuit of the collector and emitter of the transistor 10 and a parallel resistor 9 is connected in parallel to the series circuit of the relay 6 and the transistor 8. The base of the transistor 10 is connected to the connection point of the relay 6 and the transistor 8, and the base of the transistor 8 is connected to the negative side of the DC power supply 2 via the resistor 16 and the output transistor 7.

Also in this embodiment, when the switch 3 is turned on similarly to the one shown in FIG. 3, the transistor 10 is turned on by the base current flowing through the relay 6 and supplies the time circuit 1 with power through the parallel resistor 9. When 1 goes up, the transistor 8 turns on and the transistor 10 turns off. Then, the time limit circuit 1 is supplied with power via the relay 6, and the relay 6 also operates.

The embodiments shown in FIGS. 3 and 4 are so-called on-delay operation type timer devices in which the output relay 6 operates after the time limit circuit 1 has timed out. However, when the relay 6 and the parallel resistor 9 are replaced, Relay 6 when turned on
Can be operated, and the so-called one-shot operation type timer device in which the time limit circuit 1 returns the relay 6 when the time is up. Although the DC power supply 2 is used in FIGS. 3 and 4, the AC power supply 2a can be used in the embodiment shown in FIGS. 3 and 4 in the same manner as in FIG.

As described above, according to the present invention, the time-out circuit for timing the time, the output transistor that is turned on or off by the output of the time-out circuit, and the output relay that operates when the output transistor is turned on or off are provided. In a timer device driven via impedance, the output relay is connected in series with the time circuit, and a parallel resistor having a resistance value substantially the same as that of the output relay is provided, and a collector / emitter is connected in series with the output relay. A first transistor and a collector connected to
A switching means including a second transistor whose emitter is connected in series to the parallel resistance is provided, and the series circuit of the first transistor and the output relay is connected in parallel to the series circuit of the second transistor and the parallel resistance. A first transistor of the switching means is on / off controlled according to on / off of the output transistor, and a second transistor of the switching means is controlled by a base current flowing through the output relay when the first transistor is off. On-controlled and off-controlled when the first transistor is on, and the switching means is configured to switch and connect the parallel resistor and the output relay in series with a time circuit according to on / off of the output transistor. The time limit circuit before and after the time limit circuit time up Current substantially equal flows, it is possible to ensure stable operation of the timer device.

[Brief description of drawings]

1 and 2 are circuit diagrams of a timer device previously filed by the present applicant, and FIGS. 3 and 4 are wiring diagrams showing different embodiments of the timer device according to the present invention. FIG. 5 is a connection diagram showing an example of a conventional timer device. 1: Timed circuit, 2: DC power supply, 2a: AC power supply, 4: Step-down resistor,
6: Output relay, 7: Output transistor, 9: Parallel resistance, 12:
Switching means.

Claims (1)

[Scope of utility model registration request] 1. A timed circuit for measuring time, an output transistor which is turned on or off by an output of the timed circuit, and an output relay which operates when the output transistor is turned on or off, and is driven from a power source through a step-down impedance. In the timer device, the output relay is connected in series with the time circuit, and a parallel resistor having substantially the same resistance value as that of the output relay is provided, and a collector / emitter is connected in series with the output relay. A switching means including a transistor and a second transistor whose collector and emitter are connected in series to the parallel resistor is provided, and a series circuit of the first transistor and the output relay and a series circuit of the second transistor and the parallel resistor are provided. Are connected in parallel, and the first transistor of the switching means is connected to the output. ON / OFF control is performed according to ON / OFF of the transistor, and the second transistor of the switching means is ON-controlled by the base current flowing through the output relay when the first transistor is OFF, and the second transistor of the first transistor is turned ON / OFF. The timer device is off-controlled when turned on, and the switching means switches and connects the parallel resistor and the output relay in series with a time-limit circuit according to turning on / off of the output transistor.