KR101321387B1 - Apparatus for welding detection in relay - Google Patents

Abstract

PURPOSE: A deposition detecting device for a relay is provided to prevent accidents on a load side due to the malfunction or errors in a relay by detecting the deposition of the contact point of the relay using a deposition detection circuit connected to the output of the relay. CONSTITUTION: A power supply unit (10) supplies power used inside a relay. A first relay unit (20) maintains or cuts the electric connection to a load (70) by switching the contact point of the relay. A second relay unit (30) outputs a signal to control the operation of the load by switching the contact point of the relay. A deposition sensor (40) generates a sensing signal according to the switching operation status of the second relay unit and sends feedback to a control unit. A switching power generation unit (50) launches and outputs switching power for use in the deposition sensor. [Reference numerals] (10) Power supply unit; (20) First relay unit; (30) Second relay unit; (40) Deposition sensor; (50) Switching power generation unit; (60) Control unit; (70) Load

Description

Apparatus for welding detection in relay}

The present invention relates to a welding detection device of a relay to detect whether or not the contact of the relay is welded to prevent a malfunction.

In general, a relay is an electronic component that performs a function of driving electric signals and electronics, and uses a principle that the core becomes an electromagnet when a current flows through a coil core.

That is, the relay has a simple function of being turned on when power is applied to the coil and being turned off when the power supplied to the coil is cut off.

These relays need to perform on or off control depending on whether the load side conditions are met.At the same time, the relay contacts melt due to overcurrent flow or heat generation during the on or off control. Symptoms may appear.

In this case, if the welding phenomenon occurs that the relay contact melts, the relay may not operate normally, causing an operation error on the load side, which may cause an unexpected accident for an operator driving the industrial equipment on the load side using the relay. There was this.

Republic of Korea Utility Model Publication No. 20-1997-0027041 1999. 7. 15.

The present invention provides a welding device for detecting a relay which detects that a contact of a relay is welded due to overcurrent, heat, or the like, and prevents an accident on the load side due to a malfunction or an error of the relay.

Deposition detection device for a relay according to an embodiment of the present invention, the power supply for supplying the power used in the relay and the relay contacts based on the switching signal input from the control unit to maintain or disconnect the electrical connection state with the load A second relay unit connected to an output side of the first relay unit, a second relay unit which outputs a signal controlling a load side operation by switching a relay contact based on a switching signal input from the control unit, and an output side of the second relay unit; It is connected to the welding detection unit for generating a detection signal and feeding back to the control unit according to the switching operation of the second relay unit, separating the power supplied from the power supply and the external power supplied to the load, for use in the welding detection unit Switching power generating unit for oscillating and outputting the switching power, and is input from the outside The switching signal for electrical connection with the load is output to the first relay unit based on the work signal, and the switching signal for outputting a signal for controlling the operation of the load side is output to the second relay unit and fed back from the welding detection unit. The control unit may determine whether the contact point of the second relay unit is welded based on the detection signal, and if the contact point of the second relay unit is welded, the controller may output a switching signal to the first relay unit to block electrical connection with the load. have.

In this case, the above-described welding detection unit may be operated according to a switching operation when outputting a signal for driving a load from the second relay unit to the load side, and the first detection unit feeding back a detection signal generated by the operation to the control unit; And a second sensing unit which is operated according to a switching operation when outputting a signal for stopping the driving of the load from the second relay unit to the load side, and which feeds back a sensing signal generated by performing the operation to the control unit. desirable.

In addition, it is preferable that the above-described first and second detectors are configured as photo couplers.

The above-described control unit may be configured to simultaneously feed back a sensing signal from each of the first sensing unit and the second sensing unit based on the switching operation of the second relay unit, or may respectively input the first sensing unit and the second sensing unit for a preset time. If the detection signal is not fed back from the input, it is determined that the contact point of the second relay unit is welded, and if the detection signal is fed back from the first sensing unit or the second sensing unit based on the switching operation of the second relay unit, It is preferable to determine that the relay unit operates normally.

As described above, according to the welding detection device of the relay of the present invention, the welding detection circuit is directly connected to the output side of the relay, through which the contact of the relay is welded by over current, heat, etc., thereby causing an error in the operation of the relay in the controller. By blocking the, it is possible to prevent accidents that may occur on the load side due to the welding of the relay contact, thereby improving the quality of the relay used in various industrial equipment.

1 is a view schematically showing the configuration of a welding detection device of a relay according to an embodiment of the present invention,
2 is a circuit diagram showing the configuration of FIG. 1 in detail;
3 is a diagram showing a data table for determining whether welding is normal or normal based on a detection signal fed back from the welding detecting unit in the control unit of the present invention.

Hereinafter, with reference to the accompanying drawings will be described in detail the welding detection device of the relay of the present invention.

1 is a view schematically showing the configuration of the welding detection device of a relay according to an embodiment of the present invention, Figure 2 is a circuit diagram showing the configuration of Figure 1 described above in more detail, Figure 3 is a control unit of the present invention ( 60 is a table showing a data table for determining whether welding is normal or normal based on a detection signal fed back from the welding detecting unit 40.

As shown, the relay of the present invention includes a power supply unit 10, a first relay unit 20, a second relay unit 30, a welding detection unit 40, a switching power generation unit 50, and a control unit 60. And the like.

The power supply unit 10 supplies power used in the relay to each component.

The first relay unit 20 maintains an electrical connection state (ie, maintains a common output state) with the load 70 by switching a relay contact based on a switching signal input from the control unit 60. That is, in the normal relay driving state, the first relay unit 20 maintains an on state to maintain an electrical connection state with the load 70 at all times, and when it is detected that welding has occurred at the relay contact, the electrical connection with the load 70 is performed. In order to block the state, it is turned off to prevent the malfunction of the load 70.

The second relay unit 30 is connected to the output side of the first relay unit 20, and outputs a signal for controlling the operation of the load 70 side by switching the relay contact based on the switching signal input from the control unit 60 do. That is, the second relay unit 30 performs normal close (NC) output, which is a signal for driving the load 70, or normal open (NO), which is a signal for stopping driving of the load 70. Normal Open) switch to perform the output.

The welding detection unit 40 is connected to the output side of the second relay unit 30, and according to the switching operation of the second relay unit 30, a detection signal (that is, a normally closed (NC) output detection signal or a normal open (NO)). Output detection signal) is fed back to the control unit 60.

At this time, the above-described welding detection unit 40 is operated according to the switching operation when outputting a signal for driving the load from the second relay unit 30 to the load 70 side, the detection signal generated by the operation performed (I.e., a normal detecting (NC) output detection signal) to the control unit 60 and a signal for stopping the driving of the load from the second relay unit 30 to the load 70 side It is operated according to the switching operation at the time of output, and is composed of a second sensing unit 44 for feeding back a sensing signal (ie, a normal open (NO) output sensing signal) generated by the operation to the control unit 60.

In addition, the first detector 42 and the second detector 44 may be configured as a photo coupler.

The switching power generation unit 50 separates the power supplied to each component inside the relay from the power supply unit 10 and the external power supplied to the load 70, and the switching power supply for use in the welding detection unit 40. Oscillates and outputs. That is, the switching power generator 50 is a high voltage (eg, used in the internal power supply of the low voltage (for example, 24V) and the load 70 supplied from the power supply unit 10 when the relay contact of the present invention is directly detected, for example, While preventing the power of 380V from being directly connected, the switching power source is oscillated so as to recognize the detection signal fed back from the welding detecting unit 40 by the control unit 60 and supplied to the welding detecting unit 40.

The controller 60 relays a switching signal for electrical connection with the load 70 based on a user's operation signal (for example, a positive switch operation signal for a press operation when the load is press equipment). At the same time as the output to the section 20, a switching signal for outputting a signal for controlling the operation of the load 70 side is output to the second relay section 30.

In addition, the controller 60 determines whether the contact point of the second relay unit 30 is welded based on a normal closed output signal or a normal open output signal, which is a detection signal fed back from the welding detection unit 40. If it is determined that the contact point of the second relay unit 30 is welded, the first relay unit 20 outputs a switching signal for interrupting electrical connection with the load 70 to the first relay unit 20. ) Is opened to prevent the load 70 from operating.

At this time, the control unit 60, the detection signal is simultaneously fed back from the first sensing unit 42 and the second sensing unit 44 based on the switching operation of the second relay unit 20, or a predetermined time If the detection signal is not fed back from each of the first sensing unit 42 and the second sensing unit 44, the contact point of the second relay unit 30 is welded, and the second relay unit 30 is detected. When the detection signal is fed back from the first sensing unit 42 or the second sensing unit 44 based on the switching operation, the second relay unit 30 determines that it operates normally.

That is, as shown in FIG. 3, the controller 60 detects a normal closed output signal input from the first detector 42 and a normal open output input from the second detector 44. When the signal is high or low at the same time, it is determined that the contact point of the second relay unit 30 is welded, and the normal closed output signal and the second detection unit 44 input from the first detection unit 42 are detected. If the normal open (NO) output detection signals inputted from the reference signal are mutually opposite, it is determined that the second relay unit 30 operates normally.

Next, the operation of the welding detection device of the relay according to the present invention configured as described above will be described in detail.

First, when an operation signal for driving the load 70 is input according to the driving of industrial equipment by the user, the control unit 60 electrically connects the load 70 and the relay (that is, a state in which a common (COM) output is normally performed). ) Is output to the first relay unit 20, and the first relay unit 20 maintains an electrical connection with the load 70 by switching a relay contact based on the control of the controller 60.

In addition, the control unit 60 outputs a switching signal for outputting a signal for controlling the operation of the load 70 (that is, the operation of the load or the stopping or interrupting of the operating load) to the second relay unit 30. 2 The relay unit 30 performs a normal close (NC) output, which is a signal for driving the load 70 by switching a relay contact based on the control of the controller 60, or stopping the driving of the load 70. Perform normal open (NO) output.

In the operation state of the second relay unit 30, the first detection unit 42 of the welding detection unit 40 may output a signal for driving the load from the second relay unit 30 to the load 70 side. When the normal closed (NC) output detection signal is fed back to the control unit (60).

In addition, when the second detection unit 44 outputs a signal for stopping driving of the load from the second relay unit 30 to the load 70 side, the second detection unit 44 feeds back a normal open (NO) output detection signal to the control unit 60. Let's do it.

Then, when the normal closed (NC) output detection signal input from the first detection unit 42 and the normal open (NO) output detection signal input from the second detection unit 44 are simultaneously high or low, the control unit 60. Next, it is determined that the contact point of the second relay unit 30 is welded.

When it is determined that the contact point of the second relay unit 30 is welded, the control unit 60 outputs a switching signal for interrupting electrical connection with the load 70 to the first relay unit 20, and the first relay unit. In 20, the relay contact is switched based on the control of the controller 60 to cut off the electrical connection with the load 70.

On the other hand, if the normal closed (NC) output detection signal input from the first detection unit 42 and the normal open (NO) output detection signal input from the second detection unit 44 are opposite to each other in the control unit 60. It is determined that the second relay unit 30 operates normally and maintains the current state.

Accordingly, the present invention can easily detect that the relay contact is welded through the direct monitoring of the relay contact using the welding detection unit 40 to block the operation error of the relay in the control unit, thereby preventing an accident that may occur on the load side Of course, the quality of the relay can be improved.

It will be apparent to those skilled in the art that various modifications may be made to the invention without departing from the spirit and scope of the invention as defined in the following claims And changes may be made without departing from the spirit and scope of the invention.

10: power supply unit 20: first relay unit
30: second relay unit 40: welding detection unit
42: first detector 44: second detector
50: switching power generating unit 60: control unit
70: load

Claims (4)

A power supply for supplying the power used inside the relay;
A first relay unit configured to maintain or disconnect an electrical connection with a load by switching a relay contact based on a switching signal input from a control unit;
A second relay unit connected to an output side of the first relay unit and outputting a signal controlling a load side operation by switching a relay contact based on a switching signal input from a control unit;
A welding detection unit connected to an output side of the second relay unit and generating a detection signal and feeding back a control unit according to whether the switching operation of the second relay unit is performed;
A switching power generation unit for separating and outputting the power supplied from the power supply unit and the external power supply supplied to the load, and oscillating and outputting switching power for use in the welding detection unit;
Outputting a switching signal for electrical connection with a load to the first relay unit based on an operation signal input from the outside, and outputting a switching signal for outputting a signal for controlling an operation of the load side to the second relay unit, On the basis of the detection signal fed back from the welding detection unit, it is determined whether the contact point of the second relay unit is welded. 1 Control unit to output to the relay unit
Deposition detection device of a relay comprising a. The method of claim 1,
The welding detection unit,
A first sensing unit operated according to a switching operation when outputting a signal for driving a load from the second relay unit to a load side, and feeding back a sensing signal generated by performing the operation to the control unit; and
A second sensing unit which is operated according to a switching operation when outputting a signal for stopping the driving of the load from the second relay unit to the load side, and feeds back a sensing signal generated by performing the operation to the controller;
Deposition detection device of a relay comprising a. 3. The method of claim 2,
The first detector and the second detector,
Deposition detection device of a relay which is a photo coupler. 3. The method of claim 2,
The control unit,
On the basis of the switching operation of the second relay unit, a sensing signal is simultaneously fed back from the first sensing unit and the second sensing unit, or from each of the first sensing unit and the second sensing unit for a preset time. If the detection signal is not fed back, it is determined that the contact point of the second relay unit is welded,
The welding detection device of the relay, when the sensing signal is fed back from the first sensing unit or the second sensing unit based on the switching operation of the second relay unit, and determines that the second relay unit operates normally.

Images