Molded case circuit breaker

Abstract

The present invention relates to a molded case circuit breaker and, more specifically, to a molded case circuit breaker, the base assembly of which has improved insulation performance. The molded case circuit breaker according to each embodiment of the present invention is configured as follows: two molded members which constitute the base enclosure have anti-leak portions formed to protrude downwards along the contact surface of the lower surface thereof; the case has anti-leak coupling portions formed on the bottom portion thereof as grooves such that the anti-leak portions are fitted / coupled thereto; and the anti-leak portions engage with the anti-leak coupling portions so as to prevent the base enclosure from widening.

Description

Circuit breaker for wiring

[0001] The present invention relates to a circuit breaker for wiring, and more particularly, to a circuit breaker for wiring with improved insulation performance of a base assembly.

[0002] In general, a molded case circuit breaker (MCCB) is an electrical device that automatically cuts off the circuit in the event of an electrical overload or short circuit to protect the circuit and load.

[0003] A circuit breaker for wiring is largely composed of a terminal portion that can be connected to the power source side or the load side, a contact portion that includes a fixed contactor and a movable contactor that makes contact with or separates the fixed contactor to connect or separate the circuit, a switching mechanism that provides power necessary to open and close the circuit by moving the movable contactor, a trip portion that detects overcurrent or short-circuit current flowing in the circuit and induces a trip operation of the switching mechanism, and an arc extinguishing portion that extinguishes an arc that occurs when an abnormal current is interrupted.

[0004] Fig. 1 illustrates a wiring circuit breaker according to the prior art. Fig. 2 illustrates the internal structure of a wiring circuit breaker according to the prior art by cutting it along the longitudinal direction.

[0005] A circuit breaker (10) according to the prior art includes a case (11) and a cover (12) which are enclosures formed of an insulating material, a fixed contactor (21) and a movable contactor (22) which constitute a contact portion for connecting or cutting off a circuit transmitted from a power source side to a load side, a switching mechanism (40) which provides power to rotate the movable contactor (22), an arc extinguishing unit (30) which is provided to extinguish an arc generated when an accident current is cut off, a trip unit (50) which detects an abnormal current and trips the switching mechanism, etc.

[0006] Additionally, terminals (15) are provided at both ends of the outer case (11, 12) to connect a circuit to a power source or load.

[0007] Meanwhile, the contact portion (21, 22) and the contact portion (30) are separately built into the base assembly (20) placed inside the case (11).

[0008] When a fault current flows in the circuit, the trip unit (50) detects this and operates the opening / closing mechanism (40) to separate the movable contactor (22) from the fixed contactor (21) and block the flow of current. At this time, an arc (A) occurs at the contactor (21, 22).

[0009] At this time, the size (strength) of the arc is proportional to the size of the current. The arc is a state in which gas in the atmosphere is instantaneously brought into a plasma state by voltage, and the temperature at the center of the arc reaches 8,000 to 12,000℃ and has explosive expansion pressure. As a result, it has the characteristic of melting and consuming the contact part (21, 22) and deteriorating and destroying the surrounding parts, so whether the arc lasts or not has a great impact on the performance and durability of the circuit breaker. Therefore, the arc must be quickly blocked, extinguished, and discharged within the arc extinguishing part (30).

[0010] In this way, in case of a circuit breaker for wiring, the task of handling the arc when a fault current occurs is the main goal in protecting the product, load, and line by blocking the fault current, and it directly affects the performance of the circuit breaker.

[0011] The operation of the base assembly (20) when the fault current is interrupted is as follows. The base assembly (20) is illustrated in Fig. 3.

[0012] When an accident current occurs, the opening / closing mechanism (40) is operated by the action of the trip unit (50), and accordingly, the shaft (26) rotates clockwise with respect to the axis (25). At this time, an arc is generated at the contact units (21, 22), and the arc is partially cooled and extinguished while moving to the grid (31) in the arc extinguishing unit (arc chamber) (30). As the arc moves along the grid (31), the arc voltage increases, and ultimately the arc is extinguished.

[0013] In a circuit breaker for wiring, the success of the circuit breaker depends on rapid arc extinguishment. That is, the rotation speed of the shaft (26) must be fast, and the generated arc must spread quickly to the grid (31) to increase the arc voltage.

[0014] An arc (A) generated at the contact point (21, 22) due to an accident current escapes between the grid (31) of the arc-extinguishing section (30) and exits through the exhaust port (29) of the base case (28). Thereafter, it passes through the exhaust pipe (19) at the bottom of the terminal section (15) and is discharged to the outside.

[0015] Fig. 4 shows a perspective view of a case (11) and a base assembly (20) of a wiring circuit breaker according to the prior art. It is shown as viewed obliquely from above toward the power supply side.

[0016] In the case (11), a base assembly (20) is provided for each phase. In the case of three phases, three base assemblies (20) are provided. The switching mechanism (40) is placed in the middle phase (for example, the S phase in the R, S, and T phases). The power of the switching mechanism (40) is transmitted to each phase by a rotary pin (43) installed across all phases. In other words, the power of the switching mechanism (40) moves all phases together by the rotary pin (43).

[0017] Fig. 5 is a perspective view of the base assembly viewed from another side. Fig. 6 is a perspective view taken vertically along line aa in Fig. 1.

[0018] The base casing (28) of the base assembly (20) is formed from a synthetic resin molding. That is, the base casing (28) is manufactured by dividing it into left and right moldings, and then the components are installed inside and then assembled. It is formed by combining one side base casing (28a) and the other side base casing (28b).

[0019] Figure 7 shows a perspective view of the case (11).

[0020] A base assembly (20) is installed on the bottom surface (16) of the case (11).

[0021] However, in the case of the base case (28) according to the conventional technology, there is a problem that when the base case (28) is cut off, the high pressure of the arc causes the base case (28) to split left and right as shown in Fig. 5, and the oxide inside the case flows out through the gap in the base case (28), contaminating the inside of the case (11) and lowering the internal insulation performance.

[0022] The present invention has been devised to solve the above-mentioned problem, and its purpose is to provide a wiring circuit breaker that prevents the base assembly case from being opened due to arc pressure generated during blocking.

[0023] A circuit breaker according to one aspect of the present invention comprises: an outer case of the circuit breaker; and a base case installed inside the outer case and housing a contact part and an arc extinguishing part, wherein a leakage prevention part is protrudedly formed on a lower surface of the base case, and a leakage prevention joint part into which the leakage prevention part is fitted is formed as a groove on a bottom surface of the outer case.

[0024] Here, the leakage prevention part is formed along the length direction on the lower surface of the base case.

[0025] In addition, the base case is composed of a base case first body that accommodates the contact portion and the arc extinguishing portion, and a base case second body that is coupled to the base case first body.

[0026] In addition, the leak prevention part is formed at a portion where the base outer case first body and the base outer case second body come into contact with each other.

[0027] In addition, the leak prevention part is composed of a leak prevention part first body formed on the base outer case first body, and a leak prevention part second body formed on the base outer case second body.

[0028] In addition, the first body of the leak prevention part is formed on a side that contacts the second body of the base case, and the second body of the leak prevention part is formed on a side that contacts the first body of the base case.

[0029] In addition, the above-mentioned leak-preventing joints are formed along the central axis of each phase on the bottom of the outer case.

[0030] Additionally, the above-mentioned leak-prevention joint is formed between the power side exhaust pipe and the load side exhaust pipe of the case.

[0031] Additionally, a rib is formed between the leak prevention joint and the exhaust pipe of the terminal section to reinforce strength.

[0032] In addition, the above leakage prevention part has a cut-out formed in the middle part.

[0033] In addition, the above-mentioned leak-proof joint is provided with a cut portion formed in the middle portion so that a portion thereof is formed parallel to the bottom portion.

[0034] Additionally, a side leakage prevention portion is formed protrudingly on the side of the base housing.

[0035] In addition, a side leakage prevention joint is formed in the outer case to which the side leakage prevention part is joined.

[0036] In addition, the side leakage prevention part is composed of a side leakage prevention part first body formed on the base outer case first body, and a side leakage prevention part second body formed on the base outer case second body.

[0037] And, a groove is provided in which a portion is cut out on the contact surface of one of the first body of the leak prevention part or the second body of the leak prevention part, and a protrusion is provided in which a portion protrudes toward one of the first body of the leak prevention part or the second body of the leak prevention part and is fitted into the groove.

[0038] According to the circuit breaker for wiring according to each embodiment of the present invention, a leakage prevention part is formed to protrude downward along the contact surface of the lower surface of two molded parts forming the base case, and a leakage prevention joint part into which the leakage prevention part is fitted is formed as a groove on the bottom of the case, so that the leakage prevention part is engaged with the leakage prevention joint part, thereby preventing the base case from being opened.

[0039] Therefore, even if pressure is generated by the arc gas during arc interruption, the base case does not open, so metal oxide does not leak out.

[0040] Therefore, it prevents contamination occurring inside the case and prevents deterioration of insulation performance.

[0041] Figures 1 to 7 illustrate circuit breakers for wiring according to the prior art.

[0042] Figure 1 is a perspective view of a circuit breaker for wiring.

[0043] Figure 2 is a perspective view showing the internal structure of a circuit breaker cut along the longitudinal direction.

[0044] Figure 3 is a diagram of the internal structure of the base assembly.

[0045] Figure 4 is a perspective view of the base assembly and case.

[0046] Figure 5 is a perspective view of the base assembly.

[0047] Figure 6 is a perspective view taken vertically along line aa in Figure 1.

[0048] Figure 7 is a perspective view of the case.

[0049] Figures 8 to 14 illustrate a wiring circuit breaker according to one embodiment of the present invention.

[0050] Figure 8 is a perspective view of a circuit breaker for wiring. It is cut along the longitudinal and longitudinal directions.

[0051] Figure 9 is a perspective view of the base assembly.

[0052] Figure 10 is a perspective view of the case.

[0053] Figure 11 is a perspective view of a circuit breaker for wiring. It is cut along the width and length directions.

[0054] Fig. 12 is a perspective view of a base assembly and an opening / closing mechanism according to another embodiment.

[0055] Fig. 13 is a perspective view of a case according to another embodiment.

[0056] Fig. 14 is a perspective view of a case and a trip unit case according to another embodiment.

[0057] Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings. However, these drawings are intended to provide a detailed description sufficient to enable those skilled in the art to easily practice the invention, and are not intended to limit the technical spirit or scope of the present invention.

[0058] The terms “absence” or “part” used to refer to components in the present invention are not used for any limiting purpose and may be omitted.

[0059] Fig. 8 is a perspective view of a circuit breaker for wiring. It is cut along the longitudinal and longitudinal directions. Fig. 9 is a perspective view of the base assembly. Fig. 10 is a perspective view of the case. Fig. 11 is a perspective view of a circuit breaker for wiring. It is cut along the transverse and longitudinal directions. Referring to the drawings, circuit breakers for wiring according to each embodiment of the present invention will be described in detail.

[0060] A circuit breaker according to one embodiment of the present invention comprises: a case (101, 110) of a circuit breaker; and a base assembly (170) installed inside the case (101, 110) and accommodating a contact portion and an arc extinguishing portion, wherein a leakage prevention portion (173) is formed protrudingly on a lower surface of the base assembly (170), and a leakage prevention coupling portion (113) into which the leakage prevention portion (173) is fitted is formed as a groove on a bottom portion (111) of the case (101, 110).

[0061] The housing (101, 110) accommodates and supports the components of the circuit breaker. The housing (101, 110) is formed roughly in a box shape. The handle (141) of the switching mechanism (140) is exposed on the upper surface of the housing (101, 110). The handle (141) operates the switching mechanism (140) by the user's manual operating force.

[0062] The outer case (101, 110) is formed of an insulating material. The outer case (101, 110) may be composed of a case (110) positioned at the bottom and a cover (101) covering the upper part of the case. Meanwhile, an upper cover (103) is provided at the central upper part of the cover (101).

[0063] Terminal sections (130, 135) that can be connected to a power source or a load are provided on the front and rear of the outer case (101, 110). The terminal sections (130, 135) are composed of a power source terminal section (130) and a load side terminal section (135).

[0064] Terminal sections (130, 135) are provided for each phase (or each pole). For example, in the case of a three-phase circuit breaker, three terminal sections may be provided on each of the power side and the load side.

[0065] Terminals (131, 136) are provided in the terminal section (130, 135). The power terminal section (130) is provided with a power terminal (131) connected to a power circuit, and the load terminal section (135) is provided with a load terminal (136) connected to a load circuit. Each terminal (131, 136) is connected to a fixed contactor (132, 133), respectively.

[0066] At the lower end of the terminal section (130, 135), a terminal section exhaust pipe (119) is provided through which arc gas is discharged to the outside. The terminal section exhaust pipes (119) are provided on both sides of each phase. Each terminal section exhaust pipe (119) can be in contact with the terminal section exhaust pipe (119) of the adjacent phase.

[0067] A trip unit (160) for detecting an abnormal current flowing in the circuit and tripping the switching mechanism is provided in a part of the outer case (101, 110). The trip unit (160) is usually provided on the load side.

[0068] The trip unit (160) of the circuit breaker for wiring detects fault current and short-circuit current and shuts off the switching mechanism (140) to protect the load and the line. The trip unit (160) is divided into a mechanical trip unit and an electronic trip unit depending on the trip method.

[0069] Mechanical trip mechanisms include thermal trip mechanisms, which operate by the deformation of a conductor due to the current flowing through it and its resistance, and magnetic trip mechanisms, which operate by changes in magnetic flux density. Thermal trip mechanisms typically utilize bimetals, while magnetic trip mechanisms typically utilize magnets and armatures.

[0070] An electronic trip unit operates a mechanism by using a sensor that detects the current flowing through the circuit. An electronic trip unit operates a mechanism from a control panel by measuring the current flowing through a conductor.

[0071] Thermal type is a method of blocking the mechanical part by deformation of the conductor due to the current flowing in the conductor and the resistance of the conductor.

[0072] The embodiment of Fig. 8 is an example of a mechanical trip unit in which a thermal trip mechanism and a magnetic trip mechanism are combined.

[0073] The trip unit may include a heater (161) connected to a load-side terminal unit (135), a bimetal (162) coupled to the heater (161) to detect heat and bend according to the amount of heat, a magnet (163) and an armature (164) installed around the heater (161), a crossbar (165) installed so as to be rotatable by contact with the bimetal (162) or the armature (164), and a shooter (166) that is bound or released by rotation of the crossbar (165) to bind or release the nail (147) of the opening / closing mechanism unit (140).

[0074] Normally, when a small current delay is interrupted, the bimetal (162) is bent by the heat generated in the heater (161), causing the crossbar (165) to rotate and operate the switching mechanism (140), and when a large current instantaneous interruption is performed, the armature (164) is attracted by the magnetic force excited by the magnet (163), causing the crossbar (165) to rotate and operate the switching mechanism (140).

[0075] The user's operating power is transmitted to the opening / closing mechanism (140) through the handle (141). In order to transmit the power of the opening / closing mechanism (140) to each phase, a pair of rotary pins (145) are installed in the opening / closing mechanism (140). The rotary pins (145) are formed to have a length that crosses all phases and are installed in the shaft assembly (or actuator assembly) (120).

[0076] A base assembly (170) is provided. A contact portion and an arc extinguishing portion are installed in the base assembly (170). A base assembly (170) is provided for each phase.

[0077] A base assembly casing (abbreviated as base casing) (179) is provided. The base casing (171) can be formed by injection molding. The base casing (171) is formed in a roughly box shape. Contact parts (132, 133, 122, 123) and an arc extinguishing part (150) are installed in the base casing (171). An opening / closing mechanism part (140) is installed on the upper part of the base casing (171).

[0078] Contact points (fixed contact points and movable contact points) are provided. The contact points are the parts where the circuit is actually connected or disconnected.

[0079] Fixed contacts (132, 133) are fixedly installed inside the housing (101, 110). Specifically, fixed contacts (132, 133) and movable contacts (122, 123) are installed inside the base assembly (170) provided for each phase. Fixed contacts (132, 133) are connected to terminals (130, 135).

[0080] The fixed contacts (132, 133) are provided with fixed contacts (132a, 133a). The fixed contacts (132a, 133a) can be made of a material with excellent electrical conductivity and durability, such as a silver (Ag) alloy.

[0081] In the case of a double circuit breaker, fixed contacts (132, 133) are provided on the power side and the load side, respectively. That is, a power side fixed contact (132) and a load side fixed contact (133) are provided. At this time, the power side fixed contact (132) may be directly connected to the power side terminal portion (130) or may be formed integrally therewith. The load side fixed contact (133) may be connected to the load side terminal portion (135) via a trip mechanism (particularly, a heater (161)).

[0082] An arc extinguishing unit (arc extinguishing device, arc chamber) (150) is provided near the contacts (fixed contacts and movable contacts) to extinguish the arc generated during the breaking. In the case of a double-contact type circuit breaker, the arc extinguishing units (150) are provided on the power supply side and the load side, respectively. The arc extinguishing unit (150) includes a pair of side plates (151, 152) and a plurality of grids (155) coupled to the side plates (151, 152) at predetermined intervals.

[0083] A shaft assembly (120) is provided. A rotary pin (145) is installed through the shaft assembly (120). The shaft assembly (120) receives the opening and closing power of the opening and closing mechanism (140) through the rotary pin (145) and rotates. As the shaft assembly (120) rotates, the movable contacts (122, 123) also rotate and come into contact with or are separated from the fixed contacts (132, 133).

[0084] The shaft assembly (120) is composed of a shaft body (121) and a movable contactor (122, 123).

[0085] The shaft body (121) is formed in a cylindrical or cylindrical shape. An axis (125) is formed protrudingly on both flat surfaces (disk surfaces) of the shaft body (121). A pair of pin holes (129) are formed in the shaft body (121) parallel to the axis (125) and into which a rotary pin (145) can be inserted.

[0086] The movable contacts (122, 123) are rotatably installed on the shaft body (121). The movable contacts (122, 123) rotate counterclockwise or clockwise together with the shaft body (121) or independently, and contact or separate from the fixed contacts (132, 133) to energize or cut off the line.

[0087] At both ends of the movable contacts (122, 123), movable contacts (122a, 123a) that can come into contact with the fixed contacts (132a, 133a) of the fixed contacts (132, 133) are respectively provided. The movable contacts (122a, 123a) can be made of a material with excellent electrical conductivity and durability, such as a silver (Ag) alloy.

[0088] A pressure spring (126) is provided inside the shaft body (121) to provide a pressure force to the movable contacts (122, 123). The pressure spring (126) is installed between the movable contacts (122, 123) and the shaft pin (127) provided inside the shaft body (121). When the movable contacts (122, 123) are in contact with the fixed contacts (122, 123), the pressure spring (126) prevents the movable contacts (122, 123) from being easily separated from the fixed contacts (122, 123).

[0089] The movable contacts (122, 123) rotate together with the shaft body (121) in normal low-current or high-current interruption situations, but in the case of current interruption, the movable contacts (122, 123) overcome the force of the pressure spring (126) due to the sudden electromagnetic repulsion and rotate independently. In this case, the movable contacts (122, 123) come into contact with another shaft pin (127) of the shaft body (121) and stop rotating.

[0090] An arc extinguishing unit (150) is provided to extinguish the arc generated during blocking. The arc extinguishing unit (150) is installed inside the base assembly (170). The arc extinguishing unit (150) is positioned adjacent to the contact points of the fixed contacts (132, 133) and the movable contacts (122, 123).

[0091] The arc extinguishing unit (150) includes side plates (151, 152) that face each other symmetrically to form a pair of side walls, and a grid (155) formed of a plurality of iron plates and inserted in parallel at a predetermined interval into the side plates (151, 152). A plurality of grids (155) may be provided and installed in multiple layers at a predetermined interval in the side plates (151, 152). Accordingly, a passage is provided between the grids (155) through which the arc can pass. The interval when the grids (155) are installed in layers may be appropriately set in consideration of the division and attraction of the arc.

[0092] The arc extinguishing section is surrounded by side plates (151, 152) and a grid (155) to form an internal space where the arc can be extinguished. The arc extinguishing section is also called an arc chamber.

[0093] When the circuit is in a normal state, the fixed contacts (132a, 133a) of the fixed contacts (132, 133) and the movable contacts (122a, 123a) of the movable contacts (122, 123) are connected and current flows. When a fault current occurs in the circuit, the movable contacts (122, 123) are rotated by the mechanism (107), so that the movable contacts (122a, 123a) are separated from the fixed contacts (132a, 133a), and the current is cut off. At this time, an arc occurs between the movable contacts (122a, 123a) and the fixed contacts (132a, 133a). This arc is divided into short arcs as it passes between the grids (155), and the arc voltage increases. In addition, the arc voltage is further increased by the arc extinguishing gas such as SF6 present in the arc extinguishing part. Accordingly, the arc is extinguished as the emission of free electrons is suppressed. Thereafter, the arc gas is discharged to the outside through the exhaust section (179) of the base case (171) and the exhaust pipe (119) of the case (110).

[0094] An exhaust port (179) is formed at both ends of the base case (171). The exhaust port (179) is formed as a pipe or hole that is connected to the outside of a part of the base case (171). In particular, the exhaust port (179) arranged on the load side is connected from the arc extinguishing part (150) to the exhaust pipe (119) of the case (110). The exhaust port (179) is formed to a predetermined length.

[0095] A terminal mounter (180) is provided in the terminal section (130, 135) to install a power or load terminal.

[0096] The terminal mounter (180) is fitted into the exhaust pipe (119). For this purpose, insertion grooves (181) are formed on both sides of the terminal mounter (180). It is preferable that the insertion grooves (181) be formed in a shape corresponding to the outer shape of the terminal exhaust pipe (119). Usually, since the cross-section of the terminal exhaust pipe (119) is formed in a rectangular shape, it is preferable that the insertion grooves (181) be formed in a square groove shape.

[0097] Let us examine the base assembly (170) in detail. The base assembly (170) is illustrated in FIG. 9. The base assembly (170) is composed of a base case (171), contact parts (120, 132, 132) built into the base case (171), and an arc extinguishing part (150). Here, the contact parts (120, 132, 132) and the arc extinguishing part (150) are as described above.

[0098] An operating hole (172) is formed in the base case (171) to enable the rotation pin (145) to operate on the side. A portion of the shaft assembly (120) is exposed through the operating hole (172).

[0099] An exhaust section (179) is formed in the base case (171) to discharge the arc generated during blocking. The exhaust sections (179) are formed on both sides of the base case (171), that is, on the power supply side and the load side. Here, the exhaust section (179) on the power supply side may be provided at the upper part of the base case (171), and the exhaust section (179) on the load side may be provided at the lower part of the base case (171).

[0100] The base case (171) has a power terminal (131) exposed on one side and a load-side fixed contact (133) connected to a load-side terminal portion (136) exposed on the other side. Here, the power terminal (131) may be arranged at the bottom of the base case (171), and the load-side fixed contact (133) may be arranged at the top of the base case (171).

[0101] The base case (171) is a synthetic resin molded product, and is divided into two molded products in order to install a contact part (120, 132, 132) and an arc extinguishing part (150) therein. That is, the contact part (120, 132, 132) and the arc extinguishing part (150) are installed in the first molded product, and the second molded product is assembled by joining it to the first molded product. The two molded products are typically configured to divide the base case (171) in half along the length direction. These two molded products are divided into a base case first body (171a) and a base case second body (171b).

[0102] The base outer case first body (171a) and the base outer case second body (171b) are connected to each other by screw connection. For this purpose, a plurality of fastening members (191) are provided.

[0103] A leak prevention part (173) is provided to prevent arc gas from leaking through a gap that may occur between the base outer case first body (171a) and the base outer case second body (171b).

[0104] The leak prevention part (173) is formed along the length direction on the lower surface of the base case (171).

[0105] A leak prevention unit (173) is provided at the part where the base case first body (171a) and the base case second body (171b) come into contact with each other. Since the arc gas leaks when the part where the base case first body (171a) and the base case second body (171b) come into contact with each other opens up due to the arc pressure, the part where the base case first body (171a) and the base case second body (171b) come into contact is reinforced to prevent the opening up.

[0106] The leak prevention part (173) is composed of a leak prevention part first body (173a) formed on the base outer case first body (171a) and a leak prevention part second body (173b) formed on the base outer case second body (171b).

[0107] That is, the first body (173a) of the leak prevention part is formed on the inner surface (the side in contact with the second body) of the first body (171a) of the base outer case, and the second body (173b) of the leak prevention part is formed on the inner surface (the side in contact with the first body) of the second body (171b) of the base outer case. Accordingly, the cross-section of the lower part of the base outer case (171) forms a 'T' shape due to the leak prevention part (173). (See Figs. 11 and 12)

[0108] The case (110) is provided with a leak prevention joint (113) that fits into the leak prevention part (173) of the base case (171) on the bottom part (111). The leak prevention joint (113) is formed as a groove so that the leak prevention part (173) can be fitted into it.

[0109] A leak-preventing joint (113) is formed along the length direction of the bottom portion (111) of the case (110). At this time, the leak-preventing joint (113) may be provided for each phase. Here, the leak-preventing joint (113) may be formed along the central axis of each phase.

[0110] The leak prevention joint (113) is formed between the power side exhaust pipe (119a) and the load side exhaust pipe (119b) of the case (110). That is, it can be formed longer than the length of the base assembly (170). This also functions as an assembly groove when assembling the base assembly (170) to the case (110), thereby facilitating assembly.

[0111] Meanwhile, a rib (114) may be formed between the leak prevention joint (113) and the exhaust pipe (119) of the terminal section to reinforce strength.

[0112] According to a circuit breaker for wiring according to one embodiment of the present invention, a leakage prevention part (173) is formed protruding along a contact surface of a lower surface of a base case (171), and a leakage prevention joint part (113) into which the leakage prevention part (173) is fitted is formed as a groove in a bottom part (111) of a case (110), so that the leakage prevention part (173) is inserted into the leakage prevention joint part (113) to prevent the base case from being opened.

[0113] Therefore, even if pressure is generated by the arc gas during arc interruption, the base case does not open, so metal oxide does not leak out.

[0114] Therefore, it prevents contamination occurring inside the case and prevents deterioration of insulation performance.

[0115] Let us look at another embodiment of the present invention.

[0116] Figure 12 shows a perspective view of the base assembly (170) and the opening / closing mechanism (140).

[0117] The opening mechanism (140) includes a handle (141) that allows the user to provide manual power, a lever (142) coupled to the handle, a latch (143) that secures the main spring, a latch holder (144) that restrains the latch, and a nail (147) that restrains the latch holder.

[0118] A leak prevention portion (173) is formed at the bottom of the base case (171). However, here, the leak prevention portion (173) is formed with a cut portion (174) that is cut in the middle to form a groove. That is, a cut portion (174) is formed in which the middle of the leak prevention portion (173) is cut. Accordingly, the leak prevention portion (173) is divided into a first leak prevention joint portion (173-1) and a second leak prevention joint portion (173-2). The cut portion (174) can be formed as a flat portion of the lower surface where the leak prevention portion (173) is not formed, as in the prior art.

[0119] The first leak-prevention joint (173-1) is composed of a first leak-prevention joint first body (173a-1) and a first leak-prevention joint second body (173b-1), and the second leak-prevention joint (173-2) is composed of a second leak-prevention joint first body (173a-2) and a second leak-prevention joint second body (173b-2).

[0120] Figure 13 illustrates a case according to another embodiment.

[0121] The leak prevention joint (113) of the case (110) is also divided into a first leak prevention joint (113-1) and a second leak prevention joint (113-2). A cut portion (115) is provided between the first leak prevention joint (113-1) and the second leak prevention joint (113-2). The cut portion (115) forms a plane parallel to the bottom portion (111) of the case (110).

[0122] The first leak prevention part (173-1) of the base case (171) is fitted into the first leak prevention joint part (113-1) of the case (110), and the second leak prevention part (173-2) of the base case (171) is fitted into the second leak prevention joint part (113-2) of the case (110).

[0123] A plurality of leak prevention parts (173) and leak prevention joints (113) are provided, and as the length of each leak prevention part decreases, the resistance according to the arc pressure increases.

[0124] Meanwhile, a side leakage prevention part (175) is provided on the side of the base case (171). The side leakage prevention part (175) is formed to protrude along the height direction of the side of the base case (171). The side leakage prevention part (175) is composed of a side leakage prevention part first body (175a) formed on the base case first body (171a) and a side leakage prevention part second body (175b) formed on the base case second body (171b).

[0125] FIG. 14 illustrates a case and a trip unit case according to another embodiment of the present invention.

[0126] The trip unit case (105) can be placed on the load side. Here, the trip unit case (105) is an example of an electronic trip unit.

[0127] In the trip unit case (105), a side leakage prevention joint (107) is formed as a groove for each phase. A side leakage prevention part (175) is joined to the side leakage prevention joint (107).

[0128] In addition to the leakage portions (173, 113), the side leakage portion (175, 107) has increased resistance to arc pressure, thereby preventing the base case (171) from opening when blocked.

[0129] Referring to FIG. 12, another embodiment of the present invention will be described.

[0130] The leak prevention part (173A) of this embodiment includes the features of the leak prevention part (173) of the previous embodiment.

[0131] The leak prevention part (173A) is composed of a leak prevention part first body (173a) formed on the base outer case first body (171a) and a leak prevention part second body (173b) formed on the base outer case second body (171b).

[0132] That is, the first body (173a) of the leak prevention part is formed on the inner surface (the side in contact with the second body) of the first body (171a) of the base outer case, and the second body (173b) of the leak prevention part is formed on the inner surface (the side in contact with the first body) of the second body (171b) of the base outer case. Accordingly, the cross-section of the lower part of the base outer case (171) forms a 'T' shape due to the leak prevention part (173).

[0133] Here, an overlapping portion (177:177a, 177b) is provided on the contact surface of the leak prevention portion (173A).

[0134] That is, among the contact surfaces of either the first body (173a) of the leak-prevention unit or the second body (173b) of the leak-prevention unit, a groove (177a) is provided in which a portion of the upper surface is cut off, and among the contact surfaces of either the first body (173a) of the leak-prevention unit or the second body (173b) of the leak-prevention unit, a protrusion (177b) is provided in which a portion of the upper surface protrudes toward either the first body (173a) of the leak-prevention unit or the second body (173b).

[0135] In Fig. 12, an example is illustrated in which a groove (177a) is formed in the first body (173a) of the leak prevention part, and a protrusion (177b) is formed in the second body (173b) of the leak prevention part. At this time, the protrusion (177b) of the second body (173b) of the leak prevention part is fitted into the groove (177a) of the first body (173a) of the leak prevention part. The protrusion (177b) and the groove (177a) can be formed over the entire leak prevention part (173A) along the longitudinal direction of the leak prevention part (173A).

[0136] The leak prevention part (173A) is formed to overlap in the vertical direction. That is, in the previous embodiment, the leak prevention part first body (173a) and the leak prevention part second body (173b) are in contact in a straight line, whereas in this embodiment, the leak prevention part first body (173a) and the leak prevention part second body (173b) are in contact in a step shape. Therefore, the resistance to the phenomenon of the base case (171) spreading due to the arc pressure generated inside the base case (171) when blocking is further increased.

[0137] According to the circuit breaker for wiring according to each embodiment of the present invention, a leakage prevention part is formed to protrude downward along the contact surface of the lower surface of two molded parts forming the base case, and a leakage prevention joint part into which the leakage prevention part is fitted is formed as a groove on the bottom of the case, so that the leakage prevention part is engaged with the leakage prevention joint part, thereby preventing the base case from being opened.

[0138] Therefore, even if pressure is generated by the arc gas during arc interruption, the base case does not open, so metal oxide does not leak out.

[0139] Therefore, it prevents contamination occurring inside the case and prevents deterioration of insulation performance.

[0140] The embodiments described above are embodiments that implement the present invention, and those skilled in the art will appreciate that various modifications and variations can be made without departing from the essential characteristics of the present invention. Therefore, the embodiments disclosed in the present invention are intended to illustrate rather than limit the technical spirit of the present invention, and the scope of the technical spirit of the present invention is not limited by these embodiments. In other words, the protection scope of the present invention should be interpreted by the following claims, and all technical ideas within a scope equivalent thereto should be interpreted as being included within the scope of the rights of the present invention.

[0141] [Explanation of symbols]

[0142] 101 Cover

[0143] 105 Tripbu Case

[0144] 107 Side leak prevention joint

[0145] 110 cases

[0146] 111 floor

[0147] 113 Leak-proof joint

[0148] 115 cut section

[0149] 120 shaft assembly

[0150] 122,123 operative contacts

[0151] 130,135 terminal section

[0152] 132,133 fixed contacts

[0153] 140 Switching mechanism

[0154] 145 turning pin

[0155] 150 Arc Sohobu

[0156] 160 Tripbu

[0157] 170 base assembly

[0158] 171 base enclosure

[0159] 173 Leakage prevention unit

[0160] 174 incision

[0161] 175 Side leak prevention unit

[0162] 177 Overlapping section

Claims

1. Enclosure of circuit breaker for wiring; and It includes a base case installed inside the above case and accommodating a contact part and an arc extinguishing part, A leakage prevention part is formed protruding on the lower surface of the above base case, A wiring circuit breaker characterized in that a leakage prevention joint into which the leakage prevention part is fitted is formed as a groove on the bottom of the outer case.

2. A wiring circuit breaker according to claim 1, characterized in that the leakage prevention part is formed along the longitudinal direction on the lower surface of the base case.

3. In the first paragraph, the base case, A first body of a base housing that accommodates the above contact portion and the arc extinguishing portion, A wiring circuit breaker characterized by comprising a base case second body coupled to a base case first body.

4. A wiring circuit breaker according to claim 3, characterized in that the leakage prevention part is formed at a portion where the base case first body and the base case second body come into contact with each other.

5. In paragraph 4, the leakage prevention part, A first body of a leakage prevention part formed on the first body of the above base outer case, A wiring circuit breaker characterized by comprising a second body with a leakage prevention section formed on the second body of the base outer case.

6. In the fifth paragraph, the first body of the leakage prevention part is formed on the side that comes into contact with the second body of the base case, A wiring circuit breaker characterized in that the second body of the above leakage prevention part is formed on a side that comes into contact with the first body of the base case.

7. A wiring circuit breaker according to claim 1, characterized in that the leakage prevention joints are formed along the central axis of each phase on the bottom of the outer case.

8. A wiring circuit breaker according to claim 1, characterized in that the leakage prevention joint is formed between the power side exhaust pipe and the load side exhaust pipe of the outer case.

9. A wiring circuit breaker according to claim 1, characterized in that a rib is formed between the exhaust pipe of the leakage prevention joint and the terminal section to reinforce strength.

10. A circuit breaker for wiring according to claim 1, characterized in that the leakage prevention part has a cut-out part formed in the middle.

11. A circuit breaker for wiring according to claim 1, characterized in that the leakage prevention joint has a cut portion formed in the middle portion with a portion parallel to the bottom portion.

12. A wiring circuit breaker according to claim 3, characterized in that a side leakage prevention part is protrudingly formed on the side surface of the base case.

13. A wiring circuit breaker according to claim 12, characterized in that a side leakage prevention joint is formed in the outer case to which the side leakage prevention part is joined.

14. In paragraph 13, The above side leakage prevention part is, A side leakage prevention part first body formed on the above base outer case first body, A wiring circuit breaker characterized by comprising a second body having a side leakage prevention portion formed on the second body of the base outer case.

15. In the fifth paragraph, a groove is provided in which a portion is cut out on the contact surface of either the first body of the leak prevention part or the second body of the leak prevention part, A wiring circuit breaker characterized in that a contact surface of the other of the first body of the leakage prevention part or the second body of the leakage prevention part is provided with a protrusion that protrudes toward one of the first body of the leakage prevention part or the second body of the leakage prevention part and is fitted into the groove.

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