JP2901309B2 - Automatic switch with delay release function - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an automatic switch with a delay opening function.

[Prior Art] A conventional automatic switch with a delay opening function is provided with a delay circuit device that opens the automatic switch after a predetermined time has elapsed after supply of main power is stopped. As shown in FIG. 2, when the power is supplied from the main power supply 18, the control circuit 15 opens the first contact 16 and closes the second contact 17 as shown in FIG. The automatic switch is turned on by exciting the HC and the closing coil CC.

Therefore, when the power from the main power supply 18 is not supplied, the control device 15 opens the second contact 17 and makes the closing coil C
C, a fixed resistor 19 and a flywheel diode 20 constitute a closed loop. Then, a loop current I is supplied in the closed loop to supply the loop current I to the closing coil CC,
The automatic switch can be opened after a predetermined time. Further, the delay release time can be adjusted by changing the resistance value of the fixed resistor 19.

[Problems to be Solved by the Invention] However, when the automatic switch is closed, a current flows through the closing coil CC.
The resistance of the input coil CC changes due to the heat generated by the motor and the surrounding environment of the automatic switch (the resistance increases at high temperatures and decreases at low temperatures). As a result, when the resistance value increases, the energy of the closing coil CC decreases, so that the ON state of the automatic switch cannot be held for a predetermined time only by the loop current I after the power of the mail power supply is not supplied. There is a problem. Further, since the combined resistance of the fixed resistance 19 and the increased resistance value of the closing coil CC increases, the consumption rate of the loop current I increases, and a predetermined delay time cannot be obtained, and the automatic switch is opened early. There is a problem.
Conversely, the resistance value of the input coil CC decreases due to the low temperature, the fixed resistance 19 also decreases, and the combined resistance decreases. As a result, the consumption rate becomes slow and the delay time becomes longer than a predetermined value.
There is a problem that the delay release time becomes long.

An object of the present invention is to provide an automatic switch with a delay opening function that can obtain a predetermined stable delay time.

Means for Solving the Problems In order to achieve the above object, the present invention provides an automatic switch with a delay opening function provided with a solenoid having a closing coil and a holding coil connected in series. And the common terminal of the closing coil
A first switch, which is configured so as to hold a closed state by both coils, is provided, and a closed loop circuit of a diode is connected in parallel to the closed coil and a reverse bias is applied to a common terminal of the closed coil and the holding coil. The gist of the present invention is that a parallel connection is provided in the closed loop circuit with a second switch and a negative polarity thermistor whose initial resistance value is high and whose resistance value decreases when the temperature rises.

[Operation] With the above configuration, when power is not supplied, the second switch is opened to form a closed loop circuit of the negative thermistor, the diode, and the closing coil, and a loop current flows in the closed loop circuit. Then, while the power is being supplied, the input coil generates heat, and when power is no longer supplied in a state where the resistance value has increased, the heat generation reduces the resistance value of the negative polarity thermistor and controls the consumption rate of the loop current. I do. In addition, the resistance value of the closing coil changes depending on the surrounding environment of the switch, but the resistance value of the negative polarity thermistor changes oppositely to that of the closing coil, and the combined resistance value controls the rate of consumption of the loop current at which the resistance becomes constant. .

[Embodiment] An embodiment of the present invention will be described below with reference to FIG.

As shown in FIG. 1, 1 is a main power supply and 2 is a rectifier circuit connected to the main power supply 1. The rectifier circuit 2 is connected to a series circuit of a microswitch MS and an X relay 3. When the automatic switch (not shown) of the microswitch MS is turned on, the microswitch MS is turned off.

For the series circuit of the microswitch MS and the X relay 3, a diode 4, a third relay switch 5 and an X
The series circuit of the relay 6 is connected in parallel. The third relay switch 5 is always closed (demagnetized state). Further, a resistor 7 and a capacitor 8 are connected to the series circuit of the third relay switch 5 and the X relay 6.
Are connected in parallel.

Further, a Z relay 9 is connected in parallel to a series circuit of the diode 4, the third relay switch 5, and the Y relay 6. Therefore, when the Z relay 9 is excited by the supply of electric power, the Z relay 9 opens the third relay switch 5, and closes the third relay switch 5 when demagnetized.

Holding coil HC and closing coil for the Z relay 9
CC series circuits are connected in parallel. Further, a first relay switch 11 is connected in parallel as a first switch which is always open to the holding coil HC. That is, one end of the first relay switch 11 is connected to the positive electrode side, and the other end is connected to the common terminal 10 of the holding coil HC and the closing coil CC. The first relay switch 11 closes when the X relay 3 is excited, and opens when the X relay 3 is demagnetized.

A series circuit of a flywheel diode 12 serving as a reverse bias and a second relay switch 13 serving as a second switch is connected in parallel to the closing coil CC to form a closed loop circuit. The second relay switch 13 opens when the Y relay 6 is excited and closes when the Y relay 6 is demagnetized.

Furthermore, a negative polarity thermistor 14 is connected in parallel to the second relay switch 13, and the resistance value of the negative polarity thermistor 14 decreases as the initial resistance value increases and the temperature increases. The negative polarity thermistor 14 is provided so that the surrounding environment of the switch can be understood, and the negative polarity thermistor 14 is disposed so as to be in contact with or close to the closing coil CC, so that heat generated by the closing coil CC is transmitted.

The operation of the delay circuit configured as described above will be described.

First, when automatically opening the automatic switch from the open state,
Power is supplied from the main power supply 1 via the rectifier circuit 2. Then, the X relay 3 is excited, and the first relay switch 11 is closed. Therefore, the closing coil CC is excited and the automatic switch is automatically closed. At the same time as the automatic closing of the automatic switch is completed, the microswitch MS is opened, the X relay 3 is demagnetized, and the first relay switch 11 is opened. Therefore, the holding coil HC and the closing coil CC are excited, and the automatic closing is maintained with small electric power.

On the other hand, since the Z relay 9 is excited, the third relay switch 5 is opened. Therefore, the power from the rectifier circuit 2 is supplied to the capacitor 8 via the diode 4 and the resistor 7.
Is charged. Further, since the Y relay 6 is in the demagnetized state by the opening of the third relay switch 5, the second relay switch 13 keeps the closed state.

Therefore, the current flowing through the holding coil HC and the closing coil CC does not flow through the negative thermistor 14 having a high initial resistance value,
It flows through the second relay switch 13 side.

Here, when the supply of power from the main power supply 1 is stopped, the Z relay 9 is demagnetized, so that the third relay switch 5 is closed, and the electric charge charged in the capacitor 8 excites the Y relay 6, thereby causing the Y relay 6 to be excited. 6 is the second relay switch 13
Open circuit.

On the other hand, the holding coil HC and the closing coil CC are demagnetized, but the loop current caused by the self-induction of the closing coil CC causes the loop current I to flow through the closed loop circuit formed by the closing coil CC, the negative thermistor 14 and the flywheel diode 12. Flows.

Then, even if the resistance value of the closing coil CC changes due to the surrounding environment of the switch, or even if the closing coil CC generates heat due to the exciting current at the time of closing and the internal resistance increases, the negative polarity thermistor 14 However, since the heat is detected, the resistance value of the negative polarity thermistor 14 drops by an amount corresponding to the heat generation. Therefore, the closing coil CC and the negative thermistor
Since the combined resistance value of 14 does not increase and a constant combined resistance value can be always maintained, the consumption rate of the loop current I becomes constant, and a predetermined delay time is secured to open the automatic switch. Can be.

Further, the negative polarity thermistor 14 maintains a resistance value substantially the same as the initial combined resistance value even when the internal resistance of the closed coil CC changes, based on the combined resistance value of the negative polarity thermistor 14 and the closed coil CC in the initial state. What you need to do is select.

Note that the present invention is not limited to the above-described embodiment, and can be arbitrarily changed without departing from the spirit of the present invention.

[Effects of the Invention] As described in detail above, according to the present invention, since the resistance value of the negative polarity thermistor changes depending on the heat generation of the input coil and the surrounding environment, the combined resistance value of the input coil and the negative polarity thermistor is constant. And the consumption rate of the loop current can be reduced, so that a predetermined delay opening time can be obtained,
There is an effect that the delay of the automatic switch can be stably released.

[Brief description of the drawings]

FIG. 1 is an electric circuit diagram according to the present invention, and FIG. 2 is a conventional electric circuit diagram. 10 common terminal, 11 first relay switch as first switch, 12 flywheel diode, 13
A second relay switch as a second switch, 14 ... a negative thermistor, HC ... a holding coil, CC ... a closing coil.

Claims (1)

(57) [Claims] 1. An automatic switch with a delay opening function provided with a solenoid having a closing coil and a holding coil connected in series, wherein the switch is turned on to a common terminal of the holding coil and the closing coil by turning on and off the switch. A first switch, which is a circuit configured to hold a state, is provided, and a closed loop circuit of a diode is configured so as to be connected in parallel to the closing coil and to have a reverse bias at a common terminal of the closing coil and the holding coil. An automatic switch having a delay opening function, wherein a parallel connection is provided in a closed loop circuit with a second switch and a negative polarity thermistor having a high initial resistance value and a resistance value decreasing as the temperature rises.