JPH07226145A - Circuit breaker - Google Patents

Abstract

PURPOSE:To promote the travel of an arc by arc gas without arranging a separate member. CONSTITUTION:An arc traveling plate 71 is electrically connected to a fixed contact point 31, and an intermediate piece 52c of a yoke 52 of an electromagnetic release device 50 is opposed to the arc traveling plate 71, and is electrically connected to a movable contact point 32. Travel promoting surfaces 19 inclined so as to widen a mutual distance toward an arc-extinguishing grid 72 from a contact point part 30 composed of the fixed contact point 31 and the movable contact point 32, is formed on a side wall of an apparatus body 1 housing the arc traveling plate 71 and the intermediate piece 52c.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a circuit breaker for forcibly opening a contact portion when an excessive current flows in a main circuit in which the contact portion is inserted.

[0002]

2. Description of the Related Art Conventionally, in this type of circuit breaker, an arc that is generated when an excessive current flows in a main circuit in which a contact portion is inserted and the contact portion is forcibly opened is quickly extinguished. The arc running plate is electrically connected to both contacts (moving contact and fixed contact, or a pair of moving contacts) that make up the contact so that the main circuit is immediately cut off. Some arcs are transferred to both arc traveling plates, and the arcs are made to travel away from the contact points and guided to the arc extinguishing device.

Further, in order to accelerate the running of the arc, ceramic recirculation side plates are provided on both sides of the contact part, and high-pressure arc gas generated by opening the contact part is passed through the passage including the contact part, and the recirculation side plate is also provided. There is proposed a structure in which the return flow is provided to the original passage through a return passage provided on the outside of the.

[0004]

However, in the circuit breaker having the return side plate as described above, it is necessary to stand the return side plate made of ceramics on both sides of the contact portion, which leads to an increase in the number of parts. There's a problem. The present invention is intended to solve the above problems, and an object thereof is to provide a circuit breaker with a reduced number of parts.

[0005]

According to a first aspect of the present invention, a main circuit is formed by inserting a contact portion between a power source side terminal and a load side terminal, and an excessive current flows through the main circuit when the contact point is closed. In the circuit breaker that forcibly opens the contact when the
A pair of arcs that are electrically connected to each of the contacts that make up the contact part and that extend in the direction of the electromagnetic force that acts on the arc by interaction with the magnetic field around the contact part and that are arranged so as to face each other. A plate is provided, and the side walls of the space accommodating both arc traveling plates are formed so that the distance between them expands in the direction of the electromagnetic force acting on the arc.

A second aspect of the present invention is characterized in that, in the first aspect of the invention, stepwise unevenness is formed on both side walls. According to a third aspect of the invention, in the first aspect of the invention, at least one of the arc traveling plates is provided with an inclined portion that is inclined so as to increase the mutual distance as the distance from the contact portion increases.

[0007]

According to the structure of the first aspect of the invention, both side walls of the space accommodating the arc traveling plate are formed such that the distance between them expands in the direction of the electromagnetic force acting on the arc. The pressure of the arc gas is high in the region close to the contact point and distributed so as to be low in the traveling direction of the arc, and the arc gas flows in the traveling direction of the arc. That is, traveling of the arc can be promoted by the flow of the arc gas, and the arc can be extinguished quickly without providing the reflux side plate for forming the reflux path unlike the conventional configuration. As a result, it is possible to reduce the number of return side plates and reduce the number of parts.

According to the structure of the second aspect of the present invention, since the stepped unevenness is provided on both side plates of the arc traveling plate, a portion which is shaded with respect to the arc when viewed from the contact portion is generated, Even if the side wall is deteriorated by the heat of the arc, the degree of deterioration is reduced in the shadowed portion. That is, the deterioration of the side wall can be made relatively small. According to the structure of the third aspect of the invention, since the inclined portions are formed so that the distance between the arc traveling plate and the arc traveling plate increases as the distance from the contact portion increases, the arc is gradually extended and the arc is gradually extended. Increasing the voltage facilitates arc extinction and creates a pressure distribution that allows arc gas to flow away from the contacts, as well as widening the distance between the side walls, thus promoting arc travel. It will be promoted.

[0009]

【Example】

(Embodiment 1) As shown in FIG. 2, a power source side terminal 2 is provided on each side of a body 10 made of an insulating material such as synthetic resin.
0a and the load side terminal 20b are provided. Power supply side terminal 2
0a has a terminal plate 21 having a fixed contact 31 (see FIG. 3).
a is electrically connected, and the load side terminal 20b is electrically connected to the terminal plate 21b to which one end of the bimetal 61 constituting the thermal release device 60 is fixed. The fixed contact 31 and the movable contact 32 provided on the movable contact 33 together with the contact portion 30.
The movable contact 33 contacts and separates from the fixed contact 33 in accordance with the operation of the opening / closing device 40 described later. The movable contact 33 is electrically connected to one end of a coil 51 of an electromagnetic release device 50, which will be described later, via a connecting wire 37 made of a braided wire,
The other end of the coil 51 is connected to an intermediate portion of the bimetal 61 via a connecting wire 38 made of a braided wire. Therefore, when the contact portion 30 is closed, the power supply side terminal 20a-contact portion 30
A main electric path through which a current flows is formed in a path of-coil 51-bimetal 61-load side terminal 20b. Here, as the bimetal 61, either a direct heating type that bends by self-heating or an indirectly heating type that bends when heated by a heater in which plate heaters are stacked may be used.

As shown in FIG. 4, the body 10 is a body 1.
0a and the cover 10b are joined together by using a rivet 11. That is, the body 10a and the cover 10b are provided with the assembly holes 12a and 12b at four positions on the peripheral portion,
The body 10a and the cover 10b can be coupled by passing the rivets 11 through the assembly holes 12a and 12b, respectively. The body 1 is on the upper surface of the body 10.
A handle insertion hole 13 that opens in a rectangular shape when the 0a and the cover 10b are abutted is formed. As shown in FIG. 3, the handle insertion hole 13 is located inside the body 10a and the cover 10b and near the handle insertion hole 13. A cylindrical bearing 14 is provided so as to project. In the bearing hole 14a opening in the center of the bearing 14,
Each end of the handle shaft 42 that supports the handle 41 is inserted. The handle 41 is provided with an operation portion 41 a that projects to the upper surface of the body 10 through the handle insertion hole 13. That is, the handle 41 is rotatable about the handle shaft 42 within a range in which the operation portion 41 a can move in the handle insertion hole 13. An arcuate cover piece 41b centering on the handle shaft 42 is provided at the base of the operating portion 41a of the handle 41.
Is formed, and the peripheral portion of the handle insertion hole 13 in the body 10 bulges outward along the cover piece 41b.
Since the cover piece 41b is in sliding contact with the inner side surface of the body 10, the cover piece 41b shields the inside of the body 1 from being seen by the cover piece 41b even when the handle 41 is rotated, and the cover piece 41b.
Characters indicating the opening and closing of the contact portion 30 according to the operation of the handle 41 are written in b. A link support portion 41c is provided on the lower surface of the cover piece 41b, and shaft protrusions 41d are provided on both lower side surfaces of the link support portion 41c. Here, the operating portion 41a and the link supporting portion 41c are set so that the projecting directions with respect to the covering piece 41b are set so that they are not in a straight line and have a substantially V-shaped cross section. Further, the handle 41 is biased counterclockwise in FIG. 3 by a handle return spring 43, which is a scissor-shaped spring mounted around the bearing 14. That is, one end of the handle return spring 43 is
Is locked to the right end of the cover piece 41b, and the other end is locked to a trip plate 44 of the opening / closing device 40 described later.

The opening / closing device 40 is formed in a substantially U-shape, and the handle 4 is inserted into a bearing hole 45a formed at the tip of each leg.
1. The handle link 4 into which the shaft protrusion 41d provided in 1 is inserted
5 and a pair of guide pieces 46b extending substantially in a direction substantially orthogonal to the locking plate 46a and extending along the edge of the locking plate 46a at both ends of the flat plate-shaped locking plate 46a. The latch plate 46 in which the handle shaft 42 is inserted into the formed shaft hole 46c, and the bearing holes 15a provided in the bearings 15 formed in the inner surfaces of the body 10a and the cover 10b, which are inserted into the trip plate 44, are provided at respective ends of the bearing holes 15a. Part is inserted and trip plate 4
4. A shaft pin 47 for rotatably supporting 4 with respect to the body 10.
And one leg piece 48a formed in a substantially U shape has a latch plate 46
And a contact link 48 which is inserted into a link hole 45c provided at the base of both leg pieces of the handle link 45 through guide holes 46d formed in both guide pieces 46b. The other leg piece 48b of the contactor link 48 is inserted into a shaft hole 33a provided in the movable contactor 33. Here, an arcuately curved guide groove 16 convex downward in FIG. 3 is formed on the inner surface of the body 10a, and the tip end portion of the leg piece 48b of the contactor link 48 is inserted into this guide groove 16. The movement range of the contact link 48 is restricted by the guide groove 16.

The movable contact 33 has a movable contact 32 at one end.
And a spring receiving piece 33b at the other end,
It is formed in a shape having a bearing piece 33c having an opening of a shaft hole 33a into which a leg piece 48b of a contact link 48 is inserted, at a portion between the movable contact 32 and the spring receiving piece 33b. Here, one end of the movable contactor 33 formed of a plate material is bent into a substantially L shape and the corner portion is used as the movable contact 32. The arc running piece 33d is extended. A spring seat 33e (see FIG. 5) inserted into one end of a contact pressure spring 34 made of a coil spring is provided on the spring receiving piece 33b so as to project therefrom. Further, the other end of the contact pressure spring 34 is connected to the body 10 on one side.
It is housed in a spring receiving recess 35 formed on the inner surface of a. A stopper 36 is provided on the inner surface of the body 10a so as to face the opening surface of the spring receiving recess 35, and the space between the inner surface of the body 10a in which the spring receiving recess 35 is formed and the stopper 36 is formed. The contact pressure spring 34 and the spring receiving piece 33
b is inserted, and the spring force of the contact pressure spring 34 urges the spring receiving piece 33b toward the stopper 36.

The trip plate 44 has a first pressing piece 44b projecting from the upper end of the base piece 44a to one side and a base piece 4a.
The second pressing piece 44c extends downward from 4a,
Further, the arm piece 44d is formed to project from one side edge of the base piece 44a in the upper and lower intermediate portions in a direction substantially orthogonal to the base piece 44a. A shaft pin 47 is provided at the base of the arm piece 44d.
And the trip plate 44 is rotatable around the shaft pin 47. Further, a hooking groove 44e is formed on the upper edge of the tip end of the arm piece 44d, and the upper edge of the arm piece 44d is inclined so that the upper edge of the arm piece 44d becomes closer to the lower edge on the tip side of the hooking groove 44e. Further, a locking recess 44f having a shape that is opened laterally and cut upward is formed at a side edge of the base piece 44a, and one end of the handle return spring 43 is locked in the locking recess 44f. By doing so, the trip plate 44 is biased counterclockwise in FIG.

The latch plate 46 is rotatable with respect to the body 10 together with the handle 41 by the handle shaft 42, but the leg pieces 48a of the contactor link 48 inserted through the handle link 45 are the latch plate 46. Since the handle link 45 is inserted into the guide hole 46d and is pivotally supported by the shaft protrusion 41d of the handle 41,
The swing range of the latch plate 46 with respect to 1 is restricted.
Further, the lower edge of the locking piece 46a of the latch plate 46 can be engaged with the hooking groove 44e provided in the trip plate 44, and the movement of the latch plate 46 is prohibited in the engaged state.

As described above, the handle 41 and the handle shaft 4
2. The switchgear 40 including the handle return spring 43, the trip plate 44, the handle link 45, the latch link 46, the shaft pin 47, and the contactor link 48 is excessive in the main electric path when the contact portion 30 is in the closed state. When an electric current passes, it functions to open the contact portion 30 by the operation of the electromagnetic release device 50 or the thermal dynamic release device 60.

The electromagnetic release device 50 is provided with a yoke 52 formed of a magnetic material in a generally U-shape that is open upward, and the coil 51 is housed in the inner space of the yoke 52. That is, the yoke 52 includes a pair of side pieces 52 a and 52 b facing both end surfaces of the coil 51 in the axial direction, and the coil 51.
And an intermediate piece 52c that connects between the two side pieces 52a and 52b. In addition, each side piece 52a, 52
Holding grooves 52d and 52e that are open to the side are formed in b. The coil 51 is a cylindrical coil tube 5 made of an insulating material.
3 is wound around the outer circumference of the coil cylinder 53, and a flange 53a is integrally formed at one axial end of the coil tube 53,
A tapered portion 53b having an inner diameter and an outer diameter that are smaller than an axial middle portion is formed at the other end portion of the coil tube 53 in the axial direction.

A tapered portion 53b is provided in the inner space of the coil tube 53.
A movable iron core 54 having a portion having a diameter larger than the inner diameter of the coil barrel 53 is installed so as to be movable in the axial direction of the coil barrel 53, and the movable iron core 54 is attached to the end of the coil barrel 53 on the flange 53a side. The fixed iron core 55 facing the coil coil 5 partially
The coil tube 53 is attached to the coil tube 53 so as to protrude from the coil tube 3. A hooking pin 54a is integrally provided on one end surface in the moving direction of the movable iron core 54 so as to project from the end surface of the coil cylinder 53 on the side of the tapered portion 53b.
The pressing pin 57 protruding from the end surface of the flange 53a side is fixed. A hooking head 54b having a larger diameter than other parts is formed at the tip of the hooking pin 54a. A return spring 56 composed of a coil spring is interposed between the movable iron core 54 and the fixed iron core 55.
The movable iron core 54 is urged toward the tapered portion 53a side of the coil cylinder 53 by the spring force.

Both ends in the moving direction of the movable iron core 54 are formed to have a smaller diameter than the middle part, one end serves as a spring receiving portion 54c to be inserted into the return spring 56, and the other end is a tapered portion 53b of the coil cylinder 53. Is formed so that it can be inserted into the inside of the taper, and the intermediate portion has a diameter larger than the inside diameter of the tapered portion. That is, the retaining step 54d is formed between the small diameter portion and the large diameter portion of the movable iron core 54 where the hooking pin 54a is provided so as to project,
The movable iron core 54 is prevented from falling off by locking the retaining step 54d to the step formed between the intermediate portion and the tapered portion 53b on the inner circumference of the coil tube 53.

The fixed iron core 55 has one end near the movable iron core 53 in the axial direction of the coil cylinder 53 formed to have a smaller diameter than the other parts and is inserted into the return spring 56.
The outer flange 55b having a diameter larger than those of the other parts is formed at the other end. Further, a coupling protrusion 55c is provided at the center of the other end. However, if the fixed iron core 55 is inserted into the flange 53a side of the coil cylinder 53, the outer flange piece 55c abuts on the end surface of the coil cylinder 53, and the coupling protrusion 55c
Will project from the coil tube 53. Further, the pressing pin 57 fixed to the movable iron core 54 is inserted into the insertion hole 55d penetrating the fixed iron core 55 in the axial direction,
It projects from the coil tube 53.

The core member formed by mounting the movable iron core 54, the fixed iron core 55, and the return spring 56 on the coil cylinder 53 as described above has the tapered portion 53b of the coil cylinder 53 and the side piece 52a of the yoke 52. The holding groove 52d which is fitted in the holding groove 52d provided on the side piece 52b and which has the coupling projection 55c of the fixed iron core 55 provided on the side piece 52b.
It is attached to the yoke 52 by being fitted in e. Here, the side piece 52 of the coil 51 and the yoke 52
The flange 53a of the coil tube 53 is interposed between the coil 51 and the coil b, so that insulation between the coil 51 and the side piece 52b of the yoke 52 is ensured. Also, the coupling protrusion 5
5c is fitted in the holding groove 52e provided in the side piece 52b of the yoke 52, and the outer flange piece 55b is sandwiched between the flange 53a of the coil cylinder 53 and the side piece 52b.
The fixed iron core 55 is magnetically coupled to the yoke 52.

Electromagnetic release device 50 constructed as described above.
Are holding projections 17a, 17 protruding from the inner surface of the body 10a with respect to the holding grooves 52d, 52e formed in the yoke 52.
By inserting b, the body 10a is fixed at a fixed position. In addition, the holding protrusion 17 is provided on the inner surface of the body 10a.
yoke mounting grooves 18a, 1 formed near a, 17b
The yoke 52 is also fixed to the body 10a by fitting the side piece 52a of the yoke 51 to the 8b. When the yoke 52 is fixed to the body 10a, the tapered projection 53b of the coil tube 53 and the coupling projection 55c of the fixed iron core 55 are respectively formed between the inner peripheral edges of the holding grooves 52d and 52e and the tip edges of the holding projections 17a and 17b. It is sandwiched between them, and the coil cylinder 53 is fixed to a fixed position with respect to the yoke 52.

In the electromagnetic release device 50 having the above structure, when the coil 51 is energized, it is fixed to the movable iron core 54 so as to reduce the magnetic resistance of the magnetic path passing through the fixed iron core 55-yoke 52-movable iron core 54. If an attractive force acts on the iron core 55 and the passing current to the coil 51 is an excessive current such as when the load is short-circuited, the spring force of the return spring 56 is applied to move the movable iron core. 54 is moved so as to approach the fixed iron core 55. Therefore, when operated in this way, the switchgear 4
By operating 0, the contact part 30 in the closed state can be forcibly opened, and is connected to the switchgear 40 as follows.

That is, the tip of the hooking pin 54a provided on the movable iron core 54 has a shaft hole 33a in the movable contact 33.
Hole 3 formed in a portion between the movable contact 32 and the movable contact 32.
3e, and when the movable iron core 54 is attracted by the excitation of the coil 51 so as to approach the fixed iron core 55, the hooking head 54b provided at the tip of the hooking pin 54a.
Is engaged with the peripheral portion of the hooking hole 33e and pulls the movable contact 33 in the direction of separating from the fixed contact 31. Here, the hooking hole 33e is formed in the shape of a bear by connecting a locking hole having a diameter smaller than that of the hooking head 54b and an introduction hole having a diameter larger than that of the hooking head 54b. The electromagnetic releasing device 50 can be easily coupled to the movable contact 33 by introducing the hooking pin 54a into the locking hole after passing through.
Further, the tip of the pressing pin 57 fixed to the movable iron core 54 is positioned so as to face the second pressing piece 44c of the trip plate 44, and when the movable iron core 54 is attracted to the fixed iron core 55 and moves, The trip plate 44 is rotated around the shaft pin 47 in the clockwise direction in FIG.

On the other hand, the thermal release device 60 is provided with the bimetal 61 as described above, one end of the bimetal 61 is fixed to the terminal plate 21b described later, and the other end is inserted in the bending direction of the bimetal 61. The adjusting screw 62 is screwed.
The adjusting screw 62 faces the first pressing piece 44b of the trip plate 44, and the bimetal 6 is caused by an excessive current passing through the main circuit.
When 1 is curved, the trip plate 44 is pushed by the tip of the adjusting screw 62, so that the trip plate 44 is moved to the shaft pin 47.
It is adapted to rotate clockwise around in FIG.

An adjusting window 63 is opened in the vicinity of the adjusting screw 62 screwed to the bimetal 61 on the peripheral wall of the body 10. The adjustment window 63 has an insertion portion 63a formed at the upper end portion so as to be wider than other portions, and the upper edge of the adjustment window 52 is a guide surface 63b inclined downward toward the inside of the body 10. There is. Further, on both sides of the adjusting window 63, a mounting groove 63c is formed, the upper end of which is continuous with the insertion portion 63a and the lower end of which extends to the lower end of the adjusting window 63. That is, the adjustment window 63
Guide ribs 63d reaching the lower end of the adjustment window 63 are formed on both side surfaces of the body 10 while leaving the insertion portion 63a on the outer side of the body 10, and the upper and lower entire lengths of the adjustment window 63 are formed on the inner side of the body 10. By forming the guide rib 63e, the mounting groove 63c is formed between the guide ribs 63d and 63e.

By the way, the degree of bending (operation sensitivity) of the bimetal 61 with respect to the passing current varies depending on the variation of the material of the bimetal 61 and the connection position of the connecting wire 38, and therefore the operation sensitivity of the switchgear 40 (that is, the switching sensitivity). In order to prevent variations in the passing current of the main circuit when the device 40 operates, the amount of protrusion of the adjusting screw 62 screwed into the bimetal 61 from the bimetal 61 to the trip plate 44 side is adjusted. Will be required. Therefore, after the assembly, the adjusting screw 62 is operated with the adjusting window 63 opened. On the other hand, since it is not necessary to operate the adjusting screw 62 after adjusting the adjusting screw 62 once, the flexible closing plate 6 is inserted into the mounting groove 63c through the insertion portion 63a.
4 is dropped so that the adjusting window 63 is closed by the closing plate 64 so that the adjusting screw 62 is not inadvertently operated and foreign matter does not enter the inside of the body 10. The closing plate 64 is set to be substantially equal to the width of the adjustment window 63 (distance between the bottoms of the mounting grooves 63c) and substantially equal to the height dimension of the adjustment window 63 in the vertical direction. When the closing plate 64 is inserted into the adjusting window 63, the upper end of the closing plate 64 contacts the upper surface of the adjusting window 63 so that the closing plate 6 is covered.
4 cannot be removed.

By the way, the power source side terminal 20a and the load side terminal 20b are formed by bending a conductive metal plate into a substantially square V-shaped cross section, and a tightening screwed on the upper piece of the terminal metal fitting 22. The screw 23 and the terminal plates 21a and 21b which contact the lower end of the tightening screw 23 are provided. The terminal fitting 22 is a terminal storage chamber 24 formed in the body 10 and having a rectangular horizontal cross section.
It is stored in a and 24b so as to be movable up and down. That is, the terminal housing chambers 24a and 24b are the terminal fittings 2
The height of the terminal fitting 22 is larger than that of the terminal fitting 2, and the terminal fitting 22 is prevented from rotating in the terminal accommodating chambers 24a and 24b and is movable only in the vertical direction. The head of the tightening screw 23 is formed in a truncated cone shape whose upper portion has a smaller diameter than that of the lower portion.
A screw operation hole 25 having a diameter such that a part of the head of the tightening screw 23 can be inserted and the head of the tightening screw 23 does not pass through is formed in the upper walls of 4a and 24b. The diameter of the upper part of the screw operation hole 25 is the tightening screw 23.
Is smaller than the upper end of the head, and the diameter of the lower part of the screw operation hole 25 is set larger than the lower end of the head of the tightening screw 23. The tips of the terminal plates 21a and 21b are the body 1
0 is exposed on the outer side surface and is bent upward,
The terminal plate 21 with respect to the fixing groove 26 formed on the outer surface of the
By engaging the fixed projecting piece 21c formed at the tip end portions of the a and 21b, the vertical movement of the tip end portions of the terminal plates 21a and 21b is prohibited. Furthermore, the terminal storage chamber 24a,
Terminal storage chamber 24 for partitioning 24b and the internal space of the body 10
Terminal plate holding grooves 27 for positioning the terminal plates 21a and 21b are formed on the side walls of a and 24b.
The vertical movement of the terminal plates 21a, 23b is also prohibited by inserting a part of the terminal plates 21a, 21b into the.
That is, in the terminal plates 21a and 21b, the tightening screw 2
Since vertical movement is prohibited on both sides of the part that abuts on the terminal 3, even if an external force acts from the tightening screw 23, the terminal plate 21
The a and 21b are fixed in place. Here, the terminal boards 21a and 21b and the terminal storage chambers 24a and 24b
The distance from the upper wall is set to be substantially equal to the length dimension of the tightening screw 23.

However, when the tip of a flat-blade screwdriver is inserted into the screw operating hole 25 and the tightening screw 23 is rotated, the terminal fitting 22 is rotated depending on the rotating direction of the tightening screw 23.
Moves up and down, the distance between the lower piece of the terminal fitting 22 and the terminal plates 21a, 21b can be changed. That is, the lower walls of the terminal storage chambers 24a and 24b and the terminal board 21
A wiring member such as an electric wire or a bus bar is inserted into the connection hole 28 penetrating the peripheral wall of the body 10 corresponding to a portion between the terminals a and 21b, and the tightening screw 23 is rotated to rotate the terminal. By bringing the lower piece of the metal fitting 22 close to the terminal plates 21a, 21b, the wiring member is sandwiched between the terminal metal fitting 22 and the terminal plates 21a, 21b, and the electrical connection with the wiring member can be made.

A terminal board 21a constituting the power supply side terminal 20a
Has a fixed contact plate 39 bent downward on the inner side of the body 10 with respect to the terminal plate holding groove 27, and the fixed contact 31 is fixed to the lower end portion of the fixed contact plate 39. The movable contact 32 provided on the movable contact 33 faces the fixed contact 31. Further, in the fixed contact plate 39, below the fixed contact 31, a part of the arc traveling plate 71 made of a conductive plate is superposed on the surface where the fixed contact 31 projects. Arc running board 71
Is provided with a vertically extending guide piece 71a that partially overlaps with the fixed contact plate 39, and the lower end of the guide piece 71a is provided with a yoke 52 along the bottom wall of the body 10 via an inclined piece 71b that is inclined obliquely downward. Arc extinguishing piece 71 extended below the intermediate piece 52c
Continue to c. Here, the arc extinguishing grid 72 is arranged between the opposing portions of the intermediate piece 52c of the yoke 52 and the arc extinguishing piece 71c. The arc-extinguishing grid 72 has a configuration in which a plurality of arc-extinguishing plates 74 made of a conductive plate are held inside a substantially U-shaped support plate 73 made of an insulating material. Notch 7 into which the lower end of the movable contact 33 is introduced
4a is formed. The arc extinguishing grid 72 is arranged such that the arc extinguishing plate 74 is substantially parallel to the intermediate piece 52b of the yoke 52 and the arc extinguishing piece 71c of the arc traveling plate 71.
The arc extinguishing piece 71c of the arc traveling plate 71 is formed in a shape in which the width gradually increases as the distance from the inclined piece 71b increases.

However, when the movable contact 32 separates from the fixed contact 31 and an arc is generated as shown in FIG.
The arc moves downward in FIG. 3 due to the electromagnetic force generated by the magnetic field generated in the surroundings by the current flowing in 1a and the movable contact 33 and the current flowing in the arc, and one end of the arc rides on the arc traveling plate 71 and disappears. The vehicle will travel so as to approach the arc grid 72. That is, the terminal board 2
The fixed contact plate 39 provided in 1a faces the movable contact 33, and since current flows in the fixed contact plate 39 and the movable contact 33 in opposite directions, the fixed contact plate 39 is attached to the arc.
And the electromagnetic force in the direction of separating from the movable contact 33 acts. As a result, one end of the arc on the fixed contact plate 39 side moves to the arc traveling plate 71 and travels, and is guided to the arc extinguishing grid 72. In addition, since the arc traveling piece 33d is formed on the movable contact 33,
The other end of the arc travels toward the tip of the arc running piece 33d. In this way, the arc is gradually guided and extended by the arc extinguishing grid 72.

By the way, a part of the connecting wire 37 connecting the movable contact 33 and one end of the coil 51 is welded to the side piece 52a of the yoke 52 which is closer to the contact portion 30. Therefore, when one end of the arc runs along the arc traveling plate 71 and is guided to the arc extinguishing grid 72, the other end of the arc moves from the arc traveling piece 33d of the movable contact 33 to the yoke 52 as shown in FIG. 7B. The intermediate piece 52b of the yoke 52-the side piece 52a of the yoke-the connecting wire 3
The electric current flows through the path of 7-coil 51.
Since the direction of this current is opposite to the current flowing through the arc traveling plate 71, the arc is guided into the arc extinguishing grid 72 by the magnetic field generated by the current flowing through the intermediate piece 52c of the yoke 52 and the arc traveling plate 71. You will receive an electromagnetic force as if to be hit. That is, the intermediate piece 52 of the yoke 52
b has a function of forming a magnetic path in the electromagnetic release device 50,
It is also used for the function of extinguishing the arc in cooperation with the arc traveling plate 71. In other words, the intermediate piece 52b of the yoke 52 functions as one of the pair of arc traveling plates.

As shown in FIG. 1, on the both side walls of the portion of the body 1 in which the arc traveling plate 71 is housed, the traveling facilitating surfaces 19 are inclined so as to widen the distance from each other as the distance from the contact portion 30 increases. Are formed. Also, the contact point 3
The wall surface on the side opposite to the arc extinguishing grid 72 across 0 is closed. Therefore, when an arc occurs when the contact portion 30 is opened, the pressure distribution of the arc gas is as shown by the broken line in FIG. 1, and is highest in the vicinity of the contact portion 30 and low in the vicinity of the arc extinguishing grid 72. As a result, the arc gas flows toward the arc extinguishing grid 72, and the traveling direction of the arc and the flowing direction of the arc gas coincide with each other, whereby the arc is rapidly introduced into the arc extinguishing grid 72.

A mounting rail (so-called DIN rail) 80 arranged inside the distribution board or the like is provided on the lower surface of the body 10.
An attachment device is provided for detachably fixing to (see FIG. 4). The mounting rail 80 has a shape in which a brim piece 80a is integrally projecting outwardly over the entire length at the tip edges of both leg pieces of the rail body formed in a substantially U-shaped cross section. A mounting recess 81 that is orthogonal to the direction connecting the power supply side terminal 20a and the load side terminal 20b is formed on the lower surface of the body 10, and one side wall of the mounting recess 81 has an inner bottom surface of the mounting recess 81. A locking projection 82 into which one flange piece 80a of the mounting rail 80 is inserted is provided in a protruding manner. Further, the other side surface of the mounting recess 81 has a through hole 8 passing through the outer surface of the body 10.
3 is formed, and a mounting claw 84 is inserted into this through hole 83. The mounting claw 84 is provided with a claw part 84b projecting into the mounting recess 81 at the other end of a rectangular frame-shaped frame part 84a having one end projecting from the outer surface of the body 10, and the claw part 84a is provided in the frame part 84a. Part 8
A spring piece 84c having one end on the 4b side integrally connected to the frame portion 84a and the other end being a free end is provided. Spring piece 84
The c is formed in a wavy shape that repeats unevenness in the direction of the center line of the through hole 83, and the claw portion 84b is formed by locking the free end of the stepped portion 83a formed on the inner peripheral surface of the through hole 83.
The mounting claw 84 is biased in such a direction as to project into the mounting recess 81. Further, the claw portion 84b is formed with a movement restricting step portion 84d that is locked by a locking step portion 83b formed on the inner peripheral surface of the through hole 83, and the movement restricting step portion 84d attaches a mounting recess of the mounting claw 84. The amount of protrusion to 81 is restricted. Here, the claw portion 84b is formed in a shape capable of sandwiching the other flange piece 80a of the mounting rail 80 with the inner bottom surface of the mounting recess 81. Further, the lower surface of the claw portion 84b is an inclined surface 84e which is inclined upward toward the tip.

According to the above-mentioned structure, one flange piece 80a of the mounting rail 80 is inserted between the inner bottom surface of the mounting recess 81 and the locking projection 82, and the body 1 is attached to the mounting rail 80.
If you press 0, the other flange piece 80a of the mounting rail 80
When the mounting claw 84 is pushed in a direction projecting from the body 10 by the pressing force acting from the inclined surface 84e, and the claw portion 84b passes over the tip of the brim piece 80a, the spring force of the spring piece 84c causes the claw portion 84b to be recessed. The other flange piece 80 a of the mounting rail 80 is held between the inner bottom surface of the mounting recess 81 and the claw portion 84 b so as to project into the position 81. In this way, the body 10 can be fixed to the mounting rail 80. On the other hand, in order to remove the body 10 from the mounting rail 80, the tip of a flat-blade screwdriver or the like is inserted into the frame portion 84a protruding to the side surface of the body 10 and the mounting claw 84 is pulled out from the body 10. The engagement state of the claw portion 84b with respect to the brim piece 80a of the mounting rail 80 is released, and the body 10 can be removed from the mounting rail 80.

Next, the operation of the circuit breaker will be described. FIG. 5 shows a closed state of the contact portion 30, and a handle 41
The operating portion 41a of the above is tilted rightward around the handle shaft 42. At this time, the trip plate 44 moves the handle return spring 4
The spring force of 3 urges the shaft pin 47 in the counterclockwise direction around the shaft pin 47 to move the adjustment screw 62 provided on the bimetal 61 to the first position.
The pressing piece 44b is kept in contact. Further, the spring force of the contact pressure spring 34 acts on the latch plate 46 via the movable contact 33 and the contact link 48, and the contact link 48.
Since the distance between the leg piece 48a of the above and the shaft protrusion 41d provided on the handle 41 is restricted by the handle link 45, the latch plate 46 receives the spring force of the contact pressure spring 34 and rotates counterclockwise around the handle shaft 42. Be urged by. Therefore, the locking piece 46a of the latch plate 46 engages with the locking groove 44e provided in the arm piece 44d of the trip plate 44. That is, since the latch plate 46 tries to rotate clockwise, but the rotation is prohibited by the trip plate 44,
The state of FIG. 5 is maintained. In this state, the position of the latch plate 46 is fixed by the handle shaft 42 and the trip plate 44, and the handle link 45 and the contact link 48.
Will also be fixed in place. As a result, the movable contact 33 is urged counterclockwise by the spring force of the contact pressure spring 34 about the leg piece 48b of the contact link 48. That is, the movable contact 32 comes into contact with the fixed contact 31 with a contact pressure according to the spring force of the contact pressure spring 34. In this state, the positional relationship is set so that the spring receiving piece 33b of the movable contact 33 does not come into contact with the stopper 36 provided on the inner surface of the body 10.

On the other hand, as shown in FIG. 6, when the operating portion 41a of the handle 41 is tilted leftward around the handle shaft 42, the contact portion 30 is opened. That is, the handle 41
By rotating the handle shaft 42 counterclockwise, the upper end of the handle link 45 moves to the right,
An attempt is made to pull up the leg piece 48a of the contactor link 48. However, if the position of the shaft protrusion 41d moves to the right with respect to the straight line connecting the handle shaft 42 and the leg piece 48a,
The spring force of the contact pressure spring 34 acting on the handle link 45 via the movable contact 33 and the contact link 48 acts to further rotate the handle 41 counterclockwise, and the leg piece 48b of the contact link 48 guides. Move to the left along the groove 16. In this way, the leg piece 48 of the contact link 48 is
When b is moved leftward, the spring receiving piece 33b of the movable contactor 33 comes into contact with the stopper 36 provided on the inner peripheral surface of the body 10 by the spring force of the contact pressure spring 34. Here, since the spring force of the contact pressure spring 34 acts below the lower end of the stopper 36, the movable contact 33 is urged clockwise and the movable contact 32 separates from the fixed contact 31. Further, when the contact portion 30 is in the open state, the latch plate 4
6 is restricted by the leg pieces 48a of the handle link 45 and the contact link 48, rotates counterclockwise about the handle shaft 42, and comes off from the trip plate 44.

By the way, in the closed state shown in FIG. 5, when the overload state occurs and an excessive current flows in the bimetal 61 and the bimetal 61 bends, the first trip plate 44 is bent.
Adjusting screw 62 in which pressing piece 21b is screwed into bimetal 61
The coil 5 due to a short circuit on the load side.
When an excessive current flows through the movable iron core 54 and the movable iron core 54 is attracted to the fixed iron core 55, the second pressing piece 44c of the trip plate 44 is pressed by the pressing pin 57 fixed to the movable iron core. ,
In either case, the trip plate 44 rotates clockwise around the shaft pin 47 as shown in FIG. When the trip plate 44 rotates clockwise, the engagement state with the latch plate 46 is released. In the closed state, the latch plate 46 receives the spring force of the contact pressure spring 34 and the handle shaft 42 moves. Since it is biased clockwise around, the lower end of the latch plate 46 moves to the left. That is, since the leg piece 48b of the contactor link 48, which was the rotation center of the movable contactor 33 in the closed state, moves leftward along the guide groove 16, like the open state shown in FIG. The movable contact 33 is pressed against the stopper 36 by the spring force of the contact pressure spring 34, so that the movable contact 32 separates from the fixed contact 31 and enters the open state. That is, when an excessive current flows in the main circuit, the trip plate 44 rotates and the engagement state with the latch plate 46 is released, and the force that biases the latch plate 46 is released. A so-called trip operation is performed to open the contact portion 30.

(Embodiment 2) In Embodiment 1, a flat traveling promotion surface 1 is provided on the side wall of the space accommodating the arc traveling plate 71.
9 was formed, in this embodiment, as shown in FIG.
Step-like irregularities are formed on the traveling promotion surface 19. If the travel promoting surface 19 is formed in a stepwise manner as described above, a part of the travel promoting surface 19 is less likely to be exposed to the arc, and even if the travel promoting surface 19 is deteriorated by the heat of the arc, it is exposed to the arc. The degree of deterioration is reduced in a portion having a small amount. That is, the degree of deterioration of the travel promoting surface 19 as a whole can be reduced, and the travel promoting surface 19 can be reduced.
The function can be extended longer than that of the configuration of the first embodiment. The other configurations and operations are the same as those in the first embodiment, and the description thereof will be omitted.

[0039]

According to the first aspect of the present invention, since both side walls of the space accommodating the arc traveling plate are formed so that the distance between them expands in the direction of the electromagnetic force acting on the arc, the pressure of the arc gas is increased. Is high in the area close to the contact point, and is distributed so as to decrease in the direction in which the arc travels.
The arc gas flows in the traveling direction of the arc, and the traveling of the arc can be promoted by the flow of the arc gas, and the arc can be extinguished quickly without providing the reflux side plate for forming the reflux path unlike the conventional configuration. become able to. As a result, it is possible to reduce the number of the circulation side plates to reduce the number of parts, which has the advantages that the assembling operation is facilitated and the cost is reduced.

According to the second aspect of the invention, since the stepped unevenness is provided on both side plates of the arc traveling plate, a portion which is shaded with respect to the arc when seen from the contact portion is generated, and the heat of the arc causes Even if the side wall is deteriorated, the degree of deterioration is reduced in the shadowed area, and therefore, there is an advantage that the deterioration of the side wall can be made relatively small. Claim 3
Of the invention, since the inclined portion is formed such that the distance between the arc traveling plate and the contact portion increases as the distance from the contact portion increases, the arc is gradually extended to increase the arc voltage, Advantages of facilitating arc travel, as well as facilitating arc extinction and forming a pressure distribution that allows arc gas to flow away from the contact, similar to widening the distance between side walls. Have.

[Brief description of drawings]

FIG. 1 is a horizontal sectional view of a main part of a first embodiment.

FIG. 2 is a perspective view showing a first embodiment with a cover removed.

FIG. 3 is an exploded perspective view showing the first embodiment.

FIG. 4 is an external perspective view showing the first embodiment.

FIG. 5 is a cross-sectional view of Example 1 in a closed state.

FIG. 6 is a cross-sectional view of a contact opening state in the first embodiment.

FIG. 7 is a cross-sectional view of a trip state according to the first embodiment.

FIG. 8 is a horizontal sectional view of a main part of the second embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Instrument 19 Travel promotion surface 20a Power supply side terminal 20b Load side terminal 30 Contact part 52c Intermediate piece 71 Arc traveling plate 71b Inclined piece

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[Procedure amendment]

[Submission date] January 9, 1995

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] Claim 1

[Correction method] Change

[Correction content]

[Procedure Amendment 2]

[Document name to be amended] Statement

[Name of item to be corrected] Claim 3

[Correction method] Change

[Correction content]

[Procedure 3]

[Document name to be amended] Statement

[Name of item to be corrected] 0005

[Correction method] Change

[Correction content]

[0005]

According to a first aspect of the present invention, a main circuit is formed by inserting a contact portion between a power source side terminal and a load side terminal, and an excessive current flows through the main circuit when the contact point is closed. In the circuit breaker that forcibly opens the contact when the
A pair of arcs that are electrically connected to each of the contacts that make up the contact part and that extend in the direction of the electromagnetic force that acts on the arc by interaction with the magnetic field around the contact part and that are arranged so as to face each other. A plate is provided, and the side walls of the space accommodating both arc traveling plates are formed so that the distance between them expands in the direction of the electromagnetic force acting on the arc.

[Procedure amendment 4]

[Document name to be amended] Statement

[Correction target item name] 0006

[Correction method] Change

[Correction content]

A second aspect of the present invention is characterized in that, in the first aspect of the invention, stepwise unevenness is formed on both side walls. A third aspect of the present invention is characterized in that, in the first aspect of the invention, the fixed-side arc traveling plate is provided with inclined portions that are inclined so as to widen the mutual distance as the distance from the contact portion increases.

Front page continuation (72) Inventor Tomoyuki Sawada 1048, Kadoma, Kadoma, Osaka Prefecture Matsushita Electric Works Co., Ltd. (72) Hiroshi Konishi, 1048, Kadoma, Kadoma City, Osaka Matsushita Electric Works

Claims (3)

[Claims] 1. A main electric circuit in which a contact is inserted between a power source side terminal and a load side terminal is formed, and when an excessive current passes through the main electric circuit when the contact is closed, the contact is forcibly opened. In the circuit breaker, the circuit breaker is electrically connected to each contact forming the contact part and is extended in the direction of the electromagnetic force acting on the arc due to the interaction with the magnetic field around the contact part and arranged to face each other. A circuit breaker, characterized in that a pair of arc traveling plates are provided, and side walls of a space accommodating both arc traveling plates are formed so that the mutual distance expands toward the direction of the electromagnetic force acting on the arc. 2. The circuit breaker according to claim 1, wherein stepwise unevenness is formed on both side walls. 3. At least one of the arc traveling plates is provided with an inclined portion which is inclined so as to increase the mutual distance as the distance from the contact portion increases.
Circuit breaker described.