KR102508199B1 - Manual Motor Starter - Google Patents

Abstract

The present invention relates to a circuit breaker for motor protection, and more particularly, to a circuit breaker for motor protection having a trip display function in case of a short circuit accident.
A circuit breaker for motor protection according to an embodiment of the present invention includes an enclosure, a contact portion for energizing or blocking a circuit, an arc extinguishing portion for arc extinguishing generated at the contact portion when cut off, an opening/closing mechanism portion for operating a movable part of the contact portion, an overcurrent or In the circuit breaker for motor protection including a trip unit for detecting the occurrence of a fault current and tripping the opening/closing mechanism unit, the support body is inserted and fixed into the lower frame of the enclosure, and the movable unit of the contact unit and the arc extinguishing unit are installed. , The lower frame is provided with a guide portion for supporting the support body, and the support body is characterized in that a support protrusion inserted into and coupled to the guide portion protrudes.

Description

Circuit breaker for motor protection {Manual Motor Starter}

The present invention relates to a circuit breaker for motor protection, and more particularly, to a circuit breaker for motor protection having a trip display function in case of a short circuit accident.

In general, a circuit breaker for motor protection (MMS; Manual Motor Starter) is a device used for electrical circuits with a rated insulation voltage of AC 690V (frequency 50Hz or 60Hz) or less, and is installed at the front of the motor to prevent over-current and phase loss ), phase reverse, short circuit, ground fault, etc., it is a device that protects the system and load equipment by operating and shutting off the system when a fault current occurs.

1 is a perspective view of a circuit breaker for motor protection according to the prior art.

The circuit breaker for motor protection includes a detecting unit (1) that detects when a fault current such as overcurrent, phase loss, reverse phase, short circuit current, or ground fault occurs, and an operating mechanism unit that trips the circuit breaker according to the detection signal of the detection unit. mechanism) (2), a contact unit (3) that opens and closes the converter while interlocking with the operation of the opening and closing mechanism unit, and an arc generated as the contact of the contact unit is separated when cut off to extinguish and discharge to the outside An arc extinguishing unit 4 and the like are provided.

In the motor protection circuit breaker as described above, during normal energization, the moving contact (5) and the fixed contact (6) of the contact part are connected so that the current drawn into the power-side terminal is energized to the load-side terminal (7). However, when a fault current occurs, the detection unit 1 detects it and drives the opening/closing mechanism unit 2, and the movable contact of the movable contactor 5 is fixed to the fixed contactor 6 by the operation of the opening/closing mechanism unit 2. It is separated from the contact point and blocks the flow of current to the load side.

The breaking process is classified according to the current as follows.

When an overcurrent occurs, as the bimetal 8 is bent, the shift plate 9 and the shift lever 10 operate to move the latch holder 11 and release the latch 12 . Accordingly, the opening/closing mechanism unit 2 operates and presses the crossbar 13 to push down the guide mover 14 so that the movable contact 5 is separated from the fixed contact 6. Thus, the current is cut off.

When a short-circuit fault current occurs, the trip lever 16 operates by the operation of the coil unit 15 to operate the trip plate 17, and the trip plate 17 operates the latch holder 11 to release the latch 12. As a result, the blocking operation of the opening/closing mechanism unit 2, such as the above-described overcurrent trip, is performed.

Meanwhile, the enclosures 21, 22, and 23 are composed of an upper frame 21, a middle frame 22, and a lower frame 23.

Figure 2 shows the configuration of the lower frame.

Inside the lower frame 23, an arc extinguishing unit 4 and a contact unit 3 are installed.

An arc extinguishing unit 4, that is, an arc chamber is inserted and installed in the lower frame 23. The arc extinguishing unit 4 is installed on both sides of the movable contactor 5.

A movable part support 25 is inserted into the lower frame 23 . The movable part support 25 is formed in a 'c'-shaped body and is installed in the insertion groove 24 of the lower frame 23. The guide mover 14 and the movable contactor 5 are inserted into the movable part support 25.

By the way, the movable part support 25 is formed in a 'c'-shaped structure, so there is a case in which shrinkage occurs inward when parts are injected in the manufacturing process. In this case, the movable part support 25 interferes with the guide mover 14, so that the operation of the guide mover 14 is not smooth, and the movable contact point and the fixed contact point do not come into contact, resulting in poor conduction.

In addition, the moving part support 25 shrinks due to thermal deformation due to high-temperature heat generated at the time of overcurrent and short-circuit interruption, resulting in poor conduction due to interference with the guide mover 14.

The present invention has been made to solve the above problems, and its object is to provide a circuit breaker for motor protection that prevents deformation of a support body due to high temperature heat.

A circuit breaker for motor protection according to an embodiment of the present invention includes an enclosure, a contact portion for energizing or blocking a circuit, an arc extinguishing portion for extinguishing an arc roll generated at the contact portion when cut off, an opening/closing mechanism portion for operating a movable part of the contact portion, an overcurrent or In the circuit breaker for motor protection including a trip unit for detecting the occurrence of a fault current and tripping the switchgear unit,

A support body inserted into and fixed to the lower frame of the enclosure and having the movable part of the contact part and the arc-extinguishing part installed, and a guide part for supporting the support body is provided on the lower frame, and the guide part is provided on the support body. It is characterized in that the support protrusion to be inserted into and coupled to protrude.

Here, the guide part is characterized in that it is provided on the side wall or the partition wall between the phases of the lower frame.

In addition, the guide portion is characterized in that the cross section is composed of a plate or a beam with a 'L' shape.

In addition, the guide portion is characterized in that provided at each corner of the insertion groove formed on the bottom surface of the lower frame.

In addition, the guide portion is characterized in that provided on the side wall or interphase barrier rib of the lower frame.

In addition, the support body includes two wall parts facing each other spaced apart from each other by a predetermined distance, and the movable part of the contact part is installed in the space between the two wall parts.

And, the support body includes an insertion portion protruding from the side and downward, and the support protrusion is characterized in that provided on the upper portion of the insertion portion.

According to the circuit breaker for motor protection according to an embodiment of the present invention, a guide part is formed on the lower frame, and a support protrusion inserted and coupled to the guide part is provided in a support body installed on the lower frame to prevent shrinkage of the support body. Even when contraction occurs, the support body is maintained in the correct position and provides a separation space necessary for the operation of the movable contactor. Therefore, malfunction due to interference between the support body and the guide mover does not occur.

In addition, it exhibits resistance to thermal deformation caused by high-temperature and high-temperature arcs generated during interruption, ensuring long-term operating performance.

1 is a diagram showing the internal structure of a circuit breaker for motor protection according to the prior art.
2 is a configuration diagram of a lower frame portion of a circuit breaker for motor protection according to the prior art.
3 is a cross-sectional view of a circuit breaker for motor protection according to an embodiment of the present invention.
4 is a configuration diagram of a lower frame portion of a circuit breaker for motor protection according to an embodiment of the present invention.
5 is an exploded perspective view of internal components except for a lower frame in FIG. 4 .

Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings, which are intended to be described in detail so that those skilled in the art can easily practice the invention. It does not mean that the technical spirit and scope of the invention are limited.

Referring to the drawings, a circuit breaker for motor protection according to each embodiment of the present invention will be described in detail. 3 is a cross-sectional view of a circuit breaker for motor protection according to an embodiment of the present invention, and FIG. 4 is a block diagram of a lower frame portion of a circuit breaker for motor protection according to an embodiment of the present invention.

A circuit breaker for motor protection according to an embodiment of the present invention includes enclosures 181, 182, and 183, a contact portion 110 for energizing or blocking a circuit, an arc-extinguishing portion 120 for extinguishing arcs generated in the contact portion 110 when cut off, A circuit breaker for motor protection including an opening/closing mechanism unit 140 for operating the movable units 113, 115, and 117 of the contact unit 110, and a trip unit 130 for detecting the occurrence of an overcurrent or fault current and tripping the switching mechanism unit 140 In the lower frame 183, the support body 190 is inserted and fixed, and the movable parts 113, 115, 117 of the contact part 110 and the arc-extinguishing part 120 are installed; further comprising, the lower frame 183 ) is provided with a guide portion 187 for supporting the support body 190, and a support protrusion 195 inserted into the guide portion 187 is protruded from the support body 190.

A circuit breaker for motor protection according to an embodiment of the present invention includes a detecting unit 130 for detecting when a fault current such as overcurrent, phase loss, reverse phase, short circuit current, or ground fault occurs, and detection of the detection unit 130 An operating mechanism 130 that trips the circuit breaker according to a signal, a contact unit 110 that opens and closes the circuit while interlocking according to the operation of the open and close mechanism unit 140, and the contact unit 110 when shutting off. An arc extinguishing unit 120 and the like are provided to extinguish the arc generated when the contact of the 110 is separated and discharge it to the outside.

The enclosures 181, 182, and 183 install and support components therein. The enclosures 181, 182, and 183 may be formed of synthetic resin.

The contact unit 110 is fixedly installed in a part of the enclosures 181, 182, and 183 and contacts or separates the fixed contactor 111 connected to the power terminal unit 105 or the load terminal unit 106 and the fixed contactor 111 to conduct the circuit. Or it includes a movable contact 113 that blocks.

The fixed contact 111 is disposed adjacent to the terminal portions 105 and 106, respectively. Fixed contacts 112 are provided on the fixed contacts 111, respectively. The fixed contact 111 is provided with a fixed contact 112 formed of a material having excellent electrical conductivity and strong heat resistance.

The movable contact 113 is disposed at a predetermined distance from the fixed contact 111 . The movable contactor 113 is installed on a guide mover 115 and can linearly move (up and down) toward the fixed contactor 111 together with the guide mover 115 . The movable contact 113 is provided with a movable contact 114 made of a material having excellent electrical conductivity and strong heat resistance.

A contact spring 117 is disposed under the movable contact 113 to provide elastic force to the movable contact 113 or the guide mover 115 .

An arc extinguishing unit 120 is provided around the contact unit 110 . The arc extinguishing unit 120 is provided to extinguish an arc generated in the contact unit 110 when cut off. The arc extinguishing unit 120 is also referred to as an arc chamber.

The arc extinguishing unit 120 is provided with a side plate 121 and a plurality of grids 123 coupled thereto. An arc plate 125 is provided below the contact portion 110 to induce an arc to the arc extinguishing portion 120 . The arc plate 125 is also referred to as an arc runner.

A detection unit or trip unit 130 is provided to detect and trip abnormal currents such as overcurrent or fault current. The trip unit 130 includes a delay trip device for detecting overcurrent and an instantaneous trip device for detecting fault current (short circuit current).

The delay trip device is connected to the load-side terminal part 106 or the heater 133, and the bimetal 131 curved by heat generated when overcurrent flows, the moving plate 134 moving by the curvature of the bimetal 131, the above It includes a moving plate lever 135 installed on the moving plate 134 and moving, and a compensating bimetal 136 rotated by the moving plate lever 135. Through sequential interlocking movements of the bimetal 131, the moving plate 134, the moving plate lever 135, and the compensating bimetal 136, the compensating bimetal 136 moves the latch holder 141 of the opening/closing mechanism unit 140. .

The instantaneous trip device includes a coil 151 that generates an induced electromagnetic force when a fault current flows in the load-side terminal part 106, a stator 152 fixed inside the coil and a mover 153 that moves by the induced electromagnetic force, and a mover. It includes a trip lever 154 that moves by receiving the force of 153 and a trip plate 155 that moves in conjunction with the trip lever 154 and moves the latch holder 147.

An opening and closing mechanism unit 140 is provided. The user manipulates the opening/closing mechanism unit 140 to open and close the contact unit 110 to turn the circuit on or off.

The opening/closing mechanism unit 140 includes a handle 141, a joint gear 142 that converts the movement of the handle 141 in an orthogonal axial direction, and a first U pin sequentially connected and interlocked from the joint gear 142. 149, a latch 143, a second U pin 144 and a push link 145 are provided.

The first U-pin 149 is provided between the joint gear 142 and the latch 143 to push or pull the latch 143 according to the movement of the joint gear 142 .

The second u-pin 144 is provided between the push link 145 and the latch 143, and pushes or pulls the latch 143 according to the movement of the push link 145 or pushes according to the movement of the latch 143. Push or pull link 145.

The latch 143 moves according to the relative motion of the first u-pin 149 and the second u-pin 144.

The push link 145 presses the crossbar 146, and the crossbar 146 moves the guide mover 115 to open and close the contact portion 110.

The latch holder 147 binds or releases the latch 143 . The latch holder 145 is in a state of restraining the on/off engaging portion 143a of the latch 143 in normal operation, and restrains the on/off engaging portion 143a of the latch 143 when an overcurrent or short-circuit current occurs. is released to allow the trip operation to occur.

The enclosures 181 , 182 , and 183 are composed of an upper frame 181 , a middle frame 182 , and a lower frame 183 .

A part of the opening/closing mechanism 140 is inserted into the upper frame 181, and a handle 141 is installed on the upper surface of the upper frame 181 to receive a user's operating force.

An opening/closing mechanism unit 140 and a detection unit 130 are installed inside the intermediate frame 182 . In addition, terminal units 105 and 106 are formed at both ends of the intermediate frame 182 in the longitudinal direction to be connected to a power source or a load. Meanwhile, in the contact unit 110, the fixed contact 111 is fixedly installed on the lower surface of the intermediate frame 182.

The contact part 110 and the arc extinguishing part 120 are installed in the lower frame 183 .

FIG. 4 shows the lower frame 183 and its internal structure, and FIG. 5 shows an exploded perspective view of the internal components of the lower frame 183 .

The lower frame 183 is formed in a box shape with an open upper surface.

The lower frame 183 is provided with partition walls 184 between phases. For example, in the case of a three-phase circuit breaker, two phase partition walls 184 are provided. Accordingly, the lower frame 183 is provided with a lower compartment 186 partitioned by side walls 188 and partition walls 184 between phases. In the case of a three-phase circuit breaker, three lower compartments 186 are provided. In each lower compartment 186, components for each phase (eg, a contact unit and an arc extinguishing unit) may be installed.

An insertion groove 185 is formed in the middle of the bottom surface of each lower compartment 186 .

A guide part 187 is provided on the inner surface of each lower compartment 186 . That is, the guide part 187 is provided on the inner surface of each sidewall 188 of the lower frame 183 and both sides of the partition wall 184 between phases. The guide part 187 may be formed of a plate or a beam having a predetermined length. The guide part 187 is formed with a groove into which the support body 190 can be inserted. For example, the guide part 187 is formed in a 'L' shape or 'L' shape in cross section.

The guide part 187 may be provided at each corner of the insertion groove 185 . For example, the guide part 187 may be provided at each of the four corners of the insertion groove 185 .

Components installed in the lower compartment 186 will be reviewed.

An arc plate 125 is provided. The arc plate 125 is also referred to as an arc runner. The arc plate 125 guides the arc generated at the contact portion to the arc extinguishing portion 120 when it is cut off. The middle portion of the arc plate 125 may be bent and inserted into the insertion groove 185 .

A support body 190 is provided. The support body 190 is formed in a 'c' shape. That is, it includes two wall parts 191 facing each other with the bottom surface interposed therebetween. The movable parts 115, 117, and 113 of the contact part 110 are inserted into the space between the two wall parts 191. Here, the movable parts 115, 117, and 113 of the contact part 110 may include a guide mover 115, a movable contactor 113, and a contact spring 117.

At both ends of the support body 190, arc-extinguishing unit support ribs 194 supporting the arc-extinguishing unit 120 are provided. The grid 123 of the arc extinguishing unit 120 is installed and supported in the space surrounded by the arc extinguishing unit support rib 194 and the wall unit 191 .

An insertion portion 193 is provided on the outer surface of the wall portion 191 of the support body 190 . The insertion part 193 protrudes from the side and downward of the wall part 191 . The insertion part 193 is partially inserted into the insertion groove 185 of the lower compartment 186. Since the lower portion of the insertion portion 193 is inserted into the insertion groove 185 and supported, the support body 190 is stably maintained without shaking in the front, rear, left, and right directions.

The side of the insertion part 193 is inserted between adjacent guide parts 187.

A support protrusion 195 protrudes from the upper end of the insertion portion 193. The support protrusion 195 is inserted into the groove of the guide part 187. That is, when the support body 190 is assembled to the lower frame 183, the support protrusion 195 is inserted into and coupled to the guide portion 187. Accordingly, the support body 190 is disposed closely to the sidewall 188 or the interphase partition wall 184 of the lower frame 183 without contracting inwardly by receiving force directed toward the sidewall 188 or the interphase partition wall 184 .

The support protrusion 195 partially protrudes to the side of the insertion portion 193 . That is, when viewed toward the wall portion 191, the side protruding portion of the insertion portion 193 is inserted into the groove of the guide portion 187.

Since the guide part 187 fixes the support protrusion 195, the wall part 191 of the support body 190 is not deformed by heat or force.

According to the circuit breaker for motor protection according to an embodiment of the present invention, a guide part is formed on the lower frame, and a support protrusion inserted and coupled to the guide part is provided in a support body installed on the lower frame to prevent shrinkage of the support body. Even when contraction occurs, the support body is maintained in the correct position and provides a separation space necessary for the operation of the movable contactor. Therefore, malfunction due to interference between the support body and the guide mover does not occur.

In addition, it exhibits resistance to thermal deformation caused by high-temperature and high-temperature arcs generated during interruption, ensuring long-term operating performance.

The embodiments described above are embodiments implementing the present invention, and various modifications and variations may be made to those skilled in the art without departing from the essential characteristics of the present invention. Therefore, the embodiments disclosed in the present invention are not intended to limit the technical idea of the present invention, but to explain, and the scope of the technical idea of the present invention is not limited by these embodiments. That is, the protection scope of the present invention should be construed according to the following claims, and all technical ideas within the equivalent range should be construed as being included in the scope of the present invention.

110 contact
120 Sohobu
130 trip part
140 opening and closing mechanism
183 lower frame
184 interphase bulkhead
185 insertion groove
186 lower compartment
187 guide part
188 sidewall
190 support body
191 wall part
193 insert
195 support protrusion

Claims (7)

An enclosure, a contact unit that energizes or cuts off the circuit, an arc extinguishing unit that extinguishes an arc roll generated at the contact unit when it is cut off, an opening/closing mechanism unit that operates the movable part of the contact unit, detects overcurrent or fault current and trips the opening/closing mechanism unit In the circuit breaker for motor protection, which includes a trip unit for
Further comprising a support body inserted into and fixed to the lower frame of the enclosure and having the movable part of the contact part and the arc-extinguishing part installed,
The lower frame is provided with a plurality of guide parts for supporting the support body,
The circuit breaker for motor protection, characterized in that the support body is provided with an insertion portion inserted into and coupled to the plurality of guide portions, and a support protrusion inserted into the groove of the guide portion protrudes from an upper end of the insertion portion. The circuit breaker according to claim 1, wherein the guide part is provided on a sidewall of the lower frame or a partition wall between phases. 3. The circuit breaker for motor protection according to claim 2, wherein the guide part is composed of a plate or a beam having an 'L' cross section. The circuit breaker according to claim 3, wherein the guide part is provided at each corner of an insertion groove formed on a bottom surface of the lower frame. delete The circuit breaker for motor protection according to claim 1, wherein the support body includes two wall parts facing each other separated by a predetermined distance, and a movable part of the contact part is installed in a space between the two wall parts. [7] The circuit breaker of claim 6, wherein the support body includes an insertion portion protruding from the side and downward, and the support protrusion is provided on an upper portion of the insertion portion.

Images