JPS607028A - Drive circuit of auxiliary relay - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] [Technical field of invention] The present invention relates to an auxiliary relay drive circuit.

[Technical background of the invention and progress made]

Conventional auxiliary relay drive circuits include those shown in Figure 2.

In Fig. 1, the auxiliary relay l has one end connected to the control power supply positive side 2.
The other end is connected to the collector C (2JM) of a transistor 4 as a switching element via a resistor 3 which acts as a voltage drop element.

Furthermore (the emitter E of the second transistor 4 is connected to the negative side 5 of the control power supply)
The base B is connected to an auxiliary relay drive determination circuit (not shown), etc. The diode 6 is provided as a countermeasure against the back electromotive force generated in the auxiliary relay when the transistor 4 is switched. Note that a Zener diode may be used instead of the resistor as the voltage drop element.

In such a configuration ζ, the base B of the transistor 4
When a base current is supplied from the auxiliary relay drive determination circuit to Current flows and the auxiliary relay 1 is driven.

At this time, if the transistor 4 is used in the saturation region, the current flowing through the auxiliary relay 2 increases as the voltage on the positive side 2 of the control power supply increases. Therefore, power consumption increases and heat generation in the auxiliary Y-shield 11 resistor 3 also increases. Furthermore, the operation time of the auxiliary relay I becomes faster, and the operation time is significantly reduced.

On the other hand, if the transistor 4 is used in an unsaturated region, the current flowing through the auxiliary relay will not increase due to an increase in the control power supply voltage. However, the collector C of transistor 4
, a voltage is generated between emitter E, and power consumption in transistor 4 increases.

Therefore, heat generation increases, and a transistor with a large allowable power is required. Furthermore, in such a configuration, the drive current of the auxiliary relay 1 changes due to the influence of individual variations in the current amplification factors of the transistors and temperature changes. Therefore, the auxiliary relay 1 may not operate due to insufficient drive current. ,
This results in problems such as an increase in the power consumption of the auxiliary relay 1 and the drive circuit due to the increase in the drive current, and a significant variation in the operating time of the auxiliary relay 1.

[Object of the Invention] The present invention has been made to eliminate the above-mentioned drawbacks, and it is an object of the present invention to provide a drive circuit for an auxiliary relay that consumes low power and has little variation in the operating time of the auxiliary relay. [Summary of the Invention] The present invention In order to achieve the above objective, the increase in the auxiliary relay current is reduced by increasing the voltage drop value of the voltage drop element connected in series with the auxiliary relay as the control power supply voltage rises. ing.

[Embodiments of the invention]

An embodiment of the present invention will be described with reference to FIGS. 2 and 3.

In FIG. 2-5, a voltage detection section 20 and a voltage drop control section (hereinafter referred to as an impedance control section) 21 are added to the drive circuit shown in FIG.

The voltage detection section 20 includes a constant voltage diode 22 and a resistor 23.
．． 24, 25, and a transistor 26.

A series circuit including a constant voltage diode 22 and a resistor 23, 24 is inserted between the positive side 2 of the control power supply and the side 5 of the control power supply 1'1. Transistor 26 connects its emitter to resistor 2
5 to the control power supply positive side 2, the collector to the control power supply negative side 5, and the base to the connection part of the resistors 23 and 24 (: connected pz.

The impedance control section 21 includes a resistor 27.28°29
, a transistor 30. Resistor 2
7.28 series circuit is resistor 25 and transistor 26
The connection between the control power supply negative side 5 and the darkness (two are inserted).

The transistor 30 has its emitter connected to the positive side of the control power supply 2 via the resistor 29 and the auxiliary relay l, and the emitter of the transistor 4 (collector) connected to the resistor 27 and the base connected to the resistors 27 and 28.
Connection part (: connected.

Next, the operation of the second embodiment will be explained.

When the control power supply voltage is lower than the Zener voltage of the constant voltage diode 22, no base current flows through the transistor 26, and the transistor 26 is in an off state. On the other hand, when the control power supply voltage is higher than the Zener voltage of the constant voltage diode 2z, the base current of the transistor 261 flows and the transistor 26 is turned on. When transistor 4 is on and transistor 26 is off, transistor 30 is on.
A base current flows through the transistor 30, and the transistor 30 is turned on. Transistor 4 is off, or transistor 26 is off.
When the transistor 30 is turned on, no base current flows through the transistor 30, and the transistor 30 is turned off.

When the control power source voltage is lower than the Zener voltage of the constant voltage diode 22, the transistor 26 is turned off, and when the auxiliary relay drive signal, that is, the base current turns on the transistor 4, the transistor 30 turns on, and the auxiliary relay 7 has a resistor. A current 11 determined by the parallel resistance value of the resistor 3 and the resistor 29 flows. On the other hand, the control power supply voltage is constant
p, the Zener voltage of the pressure diode 22 or higher, the transistor 26 is turned on, and even if the transistor 4 is turned on by the auxiliary relay drive signal, the transistor 30 is turned on.
remains off, and a current jk 12 determined by the resistance value of resistor 3 alone is applied to auxiliary relay 1 Mj'A.

In this way, as the voltage of the control type section 7 increases, the resistance value of the resistor 1, which is connected to the auxiliary relay 1, is increased.

The control power supply pressure - auxiliary 9 relay current characteristics of the drive circuit shown in Fig. 2 are as shown in Fig.
As J- increases (Jl), the increase in current in the auxiliary relay 1 is reduced.

In the 31st button 1, auxiliary relay jji17 dynamic current 9 electrodynamic 9' to control? The present invention (auxiliary relay drive current based on two) is low when the LL source voltage voltage level pressure V2 is above.In the present invention, even if the control voltage is in the range of (1) to (2), , the auxiliary relay drive voltage jj:t: is limited to the range from 11 to 11.

It also consists of an auxiliary relay l, a resistor 3, and a transistor 4? (II) The light heat of the auxiliary relay circuit is also reduced as shown in Figure 4, and the interpolation of the auxiliary relay l is also reduced as shown in Figure 5 (2). , a is the heat generation characteristic of the conventional technology (711) auxiliary relay, and b is the characteristic when the control power supply voltage is Zener voltage 72 or higher (d) or c when the present invention is used.In the present invention, Control 4.1 If the source voltage is less than v2 111°,
The exothermic property is a (two. After all, wood) (; in Ming, ((1
1''AIII Even if the power supply voltage changes from 1 to 2 in the range ζ1, the amount of heat generated remains in the range C2 from TH to 1゛[1□.

Further, in FIG. 5, the control power supply voltage changes from ■□ to V, l.

In this case, the operation time of the auxiliary relay varies within the range of T1 to T2. Conventionally, the control voltage was changed to ■1 to ■2.
(When changing by 1, the operating time changes within the range of 'ro and 'r2.

According to this embodiment, it is possible to reduce the increase in the current of the auxiliary relay 1 due to the increase in pressure of the control power source, and it is possible to reduce the power consumption of the auxiliary relay supervisor and drive circuit. Furthermore, fluctuations in the operating time of the auxiliary relay 1 can also be reduced. Further transistor 4.26.
30 in the saturation region (U constant voltage diode 2
Zener voltage of 2, resistor 3, 23, 24.27.28
．． Setting the value of 29 (from second, transistor 4,
26.30 can use the smaller hl-each power.

Another embodiment of the invention will be described with reference to FIGS. 6 and 7.

Fig. 6 (2, overvoltage relay 6o
and the control power supply negative side 5.

In addition, a series circuit of the resistor 29 and the b contact 60b of the overvoltage relay 60 has one end connected to the control power negative side 2 (2) via the auxiliary relay 1, and the other end connected to the emitter of the transistor 4 (2). 'Next, the effects of this embodiment will be explained in two parts.

If the control power supply voltage is lower than the operating voltage of the overvoltage relay 60, the b contact 60b is closed, and when the transistor 4 is turned on, the resistors 3 and 29 are connected.

A current i, determined by the parallel resistance value Sini, is applied to the auxiliary relay 1 by 71iEA+.

On the other hand, if the control power supply voltage is equal to or higher than the operating voltage of the overvoltage relay 60, the b contact 60b becomes open, and when the transistor 4 is turned on (2. , iz flows to the auxiliary relay L.

Even in this case, the impedance of the drive circuit connected to the auxiliary relay 1 can be increased as the control voltage Δij increases, as in the embodiment shown in FIG. 2, number 1.

Furthermore, as shown in FIG. 7, an undervoltage relay 61 may be used instead of the overcurrent relay 60, and its a contact 6La may be closed when the operating voltage is below, and open when the operating voltage is above the operating voltage. stomach.

〔Effect of the invention〕

According to the present invention, as described above (2) it is possible to provide an auxiliary relay drive circuit with low power consumption and little variation during auxiliary relay operation.

[Brief explanation of drawings]

Fig. 1 is a block diagram showing a conventional auxiliary relay glue/movement circuit, Fig. 2 is a block diagram showing an embodiment of the present invention, and Figs. 6 and 7 are configuration diagrams showing another embodiment of the present invention. [... hri auxiliary relay, 2... control 'Tungen Masaii 11
1 (, 3, 29...Resistor, 4...Switzerland, 5...Control power supply negative side, 20...Voltage detection section,
21... Impedance iTj! I %l. (7317) Agent Patent Attorney Rules Nori Chika

Claims (1)

[Claims] Between the positive side and the negative side of the control power supply (a voltage drop element inserted in series with two auxiliary relays and an auxiliary relay drive signal (a switch turned on from two), and a voltage detection section that detects the control power supply voltage) . A voltage drop control section that increases the voltage drop of the voltage drop element by increasing the control power supply voltage.