CN101651068B - Three-phase moulded case circuit breaker with short circuit self-locking function - Google Patents

Three-phase moulded case circuit breaker with short circuit self-locking function Download PDF

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Publication number
CN101651068B
CN101651068B CN 200810048776 CN200810048776A CN101651068B CN 101651068 B CN101651068 B CN 101651068B CN 200810048776 CN200810048776 CN 200810048776 CN 200810048776 A CN200810048776 A CN 200810048776A CN 101651068 B CN101651068 B CN 101651068B
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China
Prior art keywords
self
circuit breaker
breaker
electromagnet
locking
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Expired - Fee Related
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CN 200810048776
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Chinese (zh)
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CN101651068A (en
Inventor
万家盛
汪志强
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Hubei Shengjia Wiring Co Ltd
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Hubei Shengjia Wiring Co Ltd
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Priority to CN 200810048776 priority Critical patent/CN101651068B/en
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Abstract

The invention relates to a three-phase moulded case circuit breaker with short circuit self-locking function. The breaker is provided with a short circuit self-locking mechanism, which is characterized by comprising a self-locking mechanism and a resetting mechanism, wherein the self-locking mechanism controls a tripping linkage device in the breaker to maintain an overcurrent protection state; and the resetting mechanism makes the tripping linkage device in the breaker to restore an original state. Because the breaker is provided with the short circuit self-locking mechanism, the breaker cannot be directly closed after the breaker is off due to a short circuit so as to remind an operator that a short circuit fault is happened and that the breaker can be closed again after causes are found and problems are solved. Under the condition of maintaining all functions of the prior breaker, the breaker additionally has the short circuit self-locking function to overcome the defect that the breaker after the short circuit is closed again to cause breaker burning or fire disasters in the prior art.

Description

Three-phase moulded case circuit breaker with short circuit self-locking function
Technical field
The invention belongs to a kind of low-voltage electrical apparatus, is a kind of three-phase moulded case circuit breaker with short circuit self-locking function specifically.
Background technology
Mainly be to consist of (Fig. 1) by shell, operating grip, self-locking gangbar, dropout linkage, movement arm and operating point (contact) at the circuit breaker (being commonly called as air switch) that uses at present, its course of work is: the manipulation operations handle makes the self-locking gangbar drive the movement arm motion, the contact is linked to each other with the sheet metal of output finish the switch closure process, simultaneously self-locking gangbar cooperates with the dropout linkage finishes closed self-locking (Fig. 2).For circuit is protected, in existing circuit breaker, also be provided with overcurrent action Agency And sheet metal protection mechanism, its course of work is: when the electric current that flows through circuit breaker surpasses the current ratings certain value, the lower end that overcurrent coil in the overcurrent actuating mechanism makes the actuating strut action of overcurrent actuating mechanism push the dropout linkage is rotated the dropout linkage, the self-locking gangbar breaks away from the dropout linkage and finishes the circuit breaker disconnection, reaches the purpose of protection; The course of work of bimetal leaf protection mechanism is: when the electric current that flows through circuit breaker surpasses the current ratings certain value; make bi-metal plate deformed and touch the rotation of dropout linkage; the self-locking gangbar breaks away from the dropout linkage and finishes the circuit breaker disconnection, reaches the purpose of protection.But; after circuit breaker disconnects; the actuating strut of its overcurrent actuating mechanism or bimetallic sector-meeting recover reset condition; when if load is short-circuited; although above-mentioned circuit breaker can be finished overcurrent protection, still exist need not to find out again close circuit breaker of circuit breaker disconnect cause (because operating personnel do not know the overcurrent protection short circuit), to such an extent as to burn circuit breaker or cause the defective of fire; this class accident of picture has repeatedly seen media.
Summary of the invention
The purpose of this invention is to provide a kind of when circuit is short-circuited, after circuit breaker disconnects, must carry out the again three-phase moulded case circuit breaker with short circuit self-locking function of close circuit breaker of reset operation (operator is short circuit to remind), to overcome the defective of burning circuit breaker in the prior art or causing fire.
To achieve these goals; the present invention is provided with short-circuit self-locking mechanism in the three-phase moulded case circuit breaker; be characterized in: short-circuit self-locking mechanism comprises self-locking mechanism and resetting device; its self-locking mechanism is the mechanism that the dropout linkage keeps the overcurrent protection state in the control circuit breaker, and its resetting device is to make the mechanism that the dropout linkage recovers reset condition in the circuit breaker.
Above-mentioned self-locking mechanism is arranged on the swingle that electromagnet in the case for circuit breaker, transducer and lower end be hinged in the case for circuit breaker by one and consists of, the upper end of its swingle contacts with the upper end of dropout linkage in the circuit breaker, resetting device is cooperated by a button that is built-in with stage clip and described swingle or dropout linkage and consists of, the button lower end is provided with a projection, stage clip in the button is when oppression state, and the projection of its button lower end is shelved in swingle or the dropout linkage; Sensor setting is by the circuit breaker inside conductor, and electromagnet is arranged on by the swingle, and the movement arm of electromagnet contacts with the pin joint top of swingle, and electromagnet is directly controlled by transducer.
Above-mentioned self-locking mechanism is made of electromagnet, a control circuit for electromagnet that is arranged in the case for circuit breaker, and electromagnet is connected with the control circuit for electromagnet line; Resetting device is connected to form by a shift knob and control circuit for electromagnet, and wherein the movement arm of electromagnet contacts with the upper end of dropout linkage in the circuit breaker.
Above-mentioned self-locking mechanism is made of the automatically controlled self-locking control circuit of electromagnet, transducer and transducer that is arranged in the case for circuit breaker, electromagnet is connected with automatically controlled self-locking control circuit line with transducer, resetting device is made of a shift knob, sensor setting is by the circuit breaker inside conductor, and wherein the movement arm of electromagnet contacts with the upper end of dropout linkage in the circuit breaker.
Because the present invention is provided with short-circuit self-locking mechanism in circuit breaker, so that the present invention is after the circuit breaker that is short-circuited disconnects phenomenon, direct close circuit breaker, reminding operator's accident that is short-circuited, close circuit breaker again after should ascertaining the reason and deal with problems.The present invention has increased short circuit self-locking function in the situation that keep original circuit breaker all functions, thus overcome in the prior art because of after the short circuit again close circuit breaker cause the defective of burning circuit breaker or causing fire.
Description of drawings
Fig. 1 is present three-phase moulded case circuit breaker off-state structural representation.
Fig. 2 is present three-phase moulded case breaker closing status architecture schematic diagram.
Fig. 3 is the embodiment of the invention 1 closure state structural representation.
Fig. 4 is the embodiment of the invention 1 self-locking state structural representation.
Fig. 5 is the stereogram of the embodiment of the invention 1.
Fig. 6 is the embodiment of the invention 3 closure state structural representations.
Fig. 7 is the embodiment of the invention 3 self-locking state structural representations.
Fig. 8 is the stereogram of the embodiment of the invention 3.
Fig. 9 is the embodiment of the invention 5 closure state structural representations.
Figure 10 is the embodiment of the invention 5 self-locking state structural representations.
Figure 11 is that tongue tube of the present invention is directly controlled the solenoid circuit schematic diagram.
Figure 12 is tongue tube control control circuit for electromagnet schematic diagram of the present invention.
Figure 13 is the automatically controlled self-locking control circuit schematic diagram of tongue tube of the present invention.
Among the figure: 1-shell, 2-operating grip, 3-self-locking gangbar, 4-dropout linkage, 5-overcurrent actuating mechanism, 6-movement arm, 7-moving contact, 8-button, 8.1-button projection, 9-swingle, 9.1-swingle groove, 10-electromagnet, 10.1-electromagnet movement arm, 11-tongue tube, 12-dropout interlock extension bar, 12.1-extension bar groove.
Embodiment
The present invention is described in further detail below in conjunction with drawings and Examples.
The present invention is in the situation that keep former breaker structure constant (all functions are constant); a short-circuit self-locking mechanism is set in circuit breaker in addition to be consisted of; short-circuit self-locking mechanism comprises self-locking mechanism and resetting device; its self-locking mechanism is the mechanism that control dropout linkage keeps the overcurrent protection state, and its resetting device is to make the dropout linkage recover the mechanism of reset condition.
Embodiment 1:
Self-locking mechanism of the present invention is made of the swingle that electromagnet, tongue tube (transducer) and a lower end of being arranged in the case for circuit breaker are hinged in the case for circuit breaker, the upper end of its swingle contacts with the upper end of dropout linkage in the circuit breaker, resetting device is made of button and a cooperation of described swingle that is built-in with stage clip, described swingle top is provided with a groove, the button lower end is provided with a projection, stage clip in the button is when oppression state, and the projection of its button lower end is shelved in the groove on swingle top; Tongue tube is arranged on by the circuit breaker inside conductor, electromagnet is arranged on by the swingle, be connected (Figure 11) respectively the movement arm of electromagnet contact with the pin joint top of swingle (Fig. 3) after the tongue tube series connection of magnet spool and three parallel connections with the three phase mains of circuit breaker input.
The operation principle of the present embodiment is: when circuit breaker is short-circuited, owing to being much higher than the rated current of circuit breaker by the electric current in any phase conductor in the circuit breaker, produce high-intensity magnetic field around the wire, make the other tongue tube adhesive of wire, magnet spool gets electric, the movement arm action of electromagnet, the promotion swingle rotates, thereby promote the dropout linkage and rotate (circuit breaker being disconnected with the overcurrent actuating mechanism), simultaneously, because the effect that the dropout linkage rotates, the projection of button lower end is broken away from the groove of swingle, make the recovery of stage clip in the button, on one side the projection of button lower end contacts (Fig. 4) with moving on the button with swingle, after even circuit breaker disconnects, swingle returns to original position, and the dropout linkage remains on trip status and can not recover, thereby so that both made the closed procedure handle, can not make breaker closing, and finish the short circuit self-locking.If need recovery operation, only need press the button, make in the swingle groove that the projection of button lower end is shelved on, the dropout gangbar could be recovered, and just closed procedure handle again makes breaker closing.
Embodiment 2:
The present invention will be that the transducer in the example 1 is directly controlled electromagnet and changed tongue tube control control circuit for electromagnet into, and by the action of control circuit (Figure 12) control electromagnet, other structures are identical with embodiment 1.
The operation principle of the present embodiment is: when circuit breaker is short-circuited, owing to being much higher than the rated current of circuit breaker by the electric current in the circuit breaker inside conductor, the tongue tube adhesive, control circuit control magnet spool gets electric, the movement arm action of electromagnet, the promotion swingle rotates, and rotates thereby promote the dropout linkage, and other principles are identical with embodiment 1.
Embodiment 3:
Self-locking mechanism of the present invention is by an electromagnet that is arranged in the case for circuit breaker, the swingle that tongue tube (transducer) and a lower end are hinged in the case for circuit breaker consists of, the upper end of its swingle contacts with the upper end of dropout linkage in the circuit breaker, the upper end of dropout linkage is provided with an extension bar that has groove, resetting device is made of button and a described extension bar cooperation that has groove that is built-in with stage clip, the button lower end is provided with a projection, stage clip in the button is when oppression state, the projection of its button lower end is shelved in the groove of extension bar, wherein: tongue tube is arranged on by the circuit breaker inside conductor, electromagnet is arranged on by the swingle, be connected (Figure 11) respectively the movement arm of electromagnet contact with the pin joint top of swingle (Fig. 6) after the tongue tube series connection of magnet spool and three parallel connections with the three phase mains of circuit breaker input.
The operation principle of the present embodiment is: when circuit breaker is short-circuited, owing to being much higher than the rated current of circuit breaker by the electric current in the circuit breaker inside conductor, produce high-intensity magnetic field around the wire, make the other tongue tube adhesive of wire, magnet spool gets electric, the movement arm action of electromagnet, the promotion swingle rotates, thereby promote the dropout linkage and rotate (circuit breaker being disconnected with the overcurrent actuating mechanism), simultaneously, because the effect that the dropout linkage rotates, the projection of button lower end is broken away from the groove of extension bar, make the recovery of stage clip in the button, on one side the projection of button lower end contacts (Fig. 7) with moving on the button with extension bar, after even circuit breaker disconnects, swingle returns to original position, and the dropout linkage remains on trip status and can not recover, thereby so that both made the closed procedure handle, can not make breaker closing, and finish the short circuit self-locking.If need recovery operation, only need press the button, make in the extension bar groove that the projection of button lower end is shelved on, the dropout gangbar could be recovered, and just closed procedure handle again makes breaker closing.
Embodiment 4:
The present invention will be that the transducer in the example 3 is directly controlled electromagnet and changed tongue tube control control circuit for electromagnet into, and by the action of control circuit (Figure 12) control electromagnet, other structures are identical with embodiment 3.
The operation principle of the present embodiment is: when circuit breaker is short-circuited, since be much higher than the rated current of circuit breaker by the electric current in the circuit breaker inside conductor, the tongue tube adhesive, and control circuit control magnet spool gets electric, the movement arm action of electromagnet, other principles are identical with embodiment 3.
Embodiment 5:
Self-locking mechanism of the present invention is made of the automatically controlled self-locking control circuit of electromagnet, tongue tube and tongue tube (Figure 13) that is arranged in the case for circuit breaker, electromagnet is connected with automatically controlled self-locking control circuit line with tongue tube, resetting device is made of a shift knob, tongue tube is arranged on by the circuit breaker inside conductor, wherein the movement arm of electromagnet contact with the upper end of dropout linkage in the circuit breaker (Fig. 9).
The operation principle of the present embodiment is: when circuit breaker is short-circuited, owing to being much higher than the rated current of circuit breaker by the electric current in the circuit breaker inside conductor, produce high-intensity magnetic field around the wire, make the other tongue tube adhesive of wire, the automatically controlled self-locking control circuit work of tongue tube, magnet spool gets electric, the movement arm action of electromagnet, movement arm promotes the dropout linkage and rotates (circuit breaker being disconnected with the overcurrent actuating mechanism), and remain on trip status and can not recover, thereby so that both made the closed procedure handle, can not make breaker closing, and finish short circuit self-locking (Figure 10).If need recovery operation, only need press the button, automatically controlled self-locking control circuit work is quit work, the magnet spool outage, the movement arm of electromagnet recovers, and the gangbar of namely threading off is recovered, and just closed procedure handle again makes breaker closing.
Tongue tube of the present invention is directly controlled solenoid circuit (Figure 11) and is made of three tongue tubes and an electromagnet coil, wherein an end of three tongue tubes links to each other with the inlet wire three phase mains of three-phase breaker of plastic casing respectively, is connected by the zero line of electromagnet coil with the three-phase breaker of plastic casing after the other end of three tongue tubes interconnects.Its principle is: when being short-circuited mutually by any one of three-phase breaker of plastic casing, the tongue tube of this phase will adhesive and that electromagnet coil is got is electric, the electromagnet action.
The power circuit of tongue tube control control circuit for electromagnet of the present invention (Figure 12) is comprised of diode D1-D3, resistance R 1, R2, R3 capacitor C 1, integrated circuit (IC) 1, comparison circuit is comprised of resistance R 4, R5, variable resistor W integrated circuit (IC) 2, short-circuit detecting circuit is comprised of instrument transformer TA, capacitor C 2 diode D7, and the control output circuit is comprised of capacitor C 3, resistance R 6, triode Q, diode D5, electromagnet coil XQ.Its principle is: when circuit is short-circuited fault, current coil induces voltage through the reference voltage comparison with the comparison circuit inverting input of the in-phase input end that is input to comparison circuit behind the diode rectification, the output high potential drives triode Q conducting, the electromagnet action promotes transmission mechanism threads off switch, cuts off the electricity supply.
The power circuit of the automatically controlled self-locking control circuit of tongue tube of the present invention (Figure 13) is comprised of diode D1-D3, resistance R 1, R2, R3 capacitor C 1, integrated circuit (IC) 1, comparison circuit is comprised of resistance R 4, R5, variable resistor W integrated circuit (IC) 2, short-circuit detecting circuit is comprised of instrument transformer TA, capacitor C 2 diode D7, latching circuit is comprised of diode D6, release circuit is comprised of sensitive switch REST, and the control output circuit is comprised of capacitor C 3, resistance R 6, triode Q, diode D5, electromagnet coil XQ.Its principle is: when circuit is short-circuited fault, current coil induces voltage through the reference voltage comparison with the comparison circuit inverting input of the in-phase input end that is input to comparison circuit behind the diode rectification, the output high potential drives triode Q conducting, this high potential makes the circuit self-locking by the in-phase input end that diode D6 feeds back to comparator simultaneously, all the time be in high potential state, the electromagnet action promotes transmission mechanism threads off switch, cut off the electricity supply, only having by pressing the REST switch makes the output of comparator become earth potential, triode cut-off electromagnet is failure to actuate, and switch could close a floodgate.
The present invention also can be set to conventional overcurrent by short circuit current, finishes overcurrent self-locking, makes the present invention be transformed into a kind of circuit breaker with overcurrent self-locking function, is provided with the malfunction display unit at circuit breaker.
The content that is not described in detail in this specification belongs to the known prior art of this area professional and technical personnel.

Claims (3)

1. three-phase moulded case circuit breaker with short circuit self-locking function, in the three-phase moulded case circuit breaker, be provided with the short circuit self-locking device, described short circuit self-locking device comprises self-locking mechanism and resetting device, described self-locking mechanism is the mechanism that the dropout linkage keeps the overcurrent protection state in the control circuit breaker, described resetting device is to make the mechanism that the dropout linkage recovers reset condition in the circuit breaker, it is characterized in that: described self-locking mechanism is made of electromagnet, a control circuit for electromagnet that is arranged in the case for circuit breaker, and electromagnet is connected with the control circuit for electromagnet line; Described resetting device is connected to form by a shift knob and control circuit for electromagnet, and wherein the movement arm of electromagnet contacts with the upper end of dropout linkage in the circuit breaker.
2. the three-phase moulded case circuit breaker with short circuit self-locking function as claimed in claim 1, it is characterized in that: control circuit for electromagnet is made of transducer and the automatically controlled self-locking control circuit of transducer, electromagnet is connected with the automatically controlled self-locking control circuit line of transducer and described transducer, and sensor setting is by the circuit breaker inside conductor.
3. the three-phase moulded case circuit breaker with short circuit self-locking function as claimed in claim 2, it is characterized in that: described transducer is tongue tube, self-locking mechanism is made of the automatically controlled self-locking control circuit of electromagnet, tongue tube and tongue tube that is arranged in the case for circuit breaker, electromagnet is connected with the automatically controlled self-locking control circuit of tongue tube and tongue tube, tongue tube is arranged on by the circuit breaker inside conductor, by the action of the automatically controlled self-locking control circuit control of tongue tube electromagnet.
CN 200810048776 2008-08-12 2008-08-12 Three-phase moulded case circuit breaker with short circuit self-locking function Expired - Fee Related CN101651068B (en)

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Application Number Priority Date Filing Date Title
CN 200810048776 CN101651068B (en) 2008-08-12 2008-08-12 Three-phase moulded case circuit breaker with short circuit self-locking function

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Application Number Priority Date Filing Date Title
CN 200810048776 CN101651068B (en) 2008-08-12 2008-08-12 Three-phase moulded case circuit breaker with short circuit self-locking function

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CN101651068A CN101651068A (en) 2010-02-17
CN101651068B true CN101651068B (en) 2013-01-23

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Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102097257B (en) * 2011-01-30 2014-08-13 湖北盛佳电器设备有限公司 Moulded case circuit breaker (MCCB) with self-locking function
CN106356262B (en) * 2016-11-24 2018-04-10 天津航空机电有限公司 A kind of drive link of breaker for Multiphase Parallel control

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1077459A2 (en) * 1999-08-18 2001-02-21 Eaton Corporation Multi-pole circuit breaker with multiple trip bars
CN1457073A (en) * 2002-05-01 2003-11-19 莱维顿制造有限公司 Reset shutting and trip of circuit breaker
CN1744253A (en) * 2004-09-01 2006-03-08 陈贵 Grounded failure circuit breaker with reverse wiring protection function
CN2938383Y (en) * 2006-08-30 2007-08-22 刘本鹊 Electromagnetic leakage switch
CN201302962Y (en) * 2008-08-12 2009-09-02 湖北盛佳电器设备有限公司 Three-phase molded case circuit breaker with short-circuit self-locking function

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1077459A2 (en) * 1999-08-18 2001-02-21 Eaton Corporation Multi-pole circuit breaker with multiple trip bars
CN1457073A (en) * 2002-05-01 2003-11-19 莱维顿制造有限公司 Reset shutting and trip of circuit breaker
CN1744253A (en) * 2004-09-01 2006-03-08 陈贵 Grounded failure circuit breaker with reverse wiring protection function
CN2938383Y (en) * 2006-08-30 2007-08-22 刘本鹊 Electromagnetic leakage switch
CN201302962Y (en) * 2008-08-12 2009-09-02 湖北盛佳电器设备有限公司 Three-phase molded case circuit breaker with short-circuit self-locking function

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