JPH0423367B2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field] The present invention relates to a circuit breaker that is interposed between a power source and a load and is capable of cutting off power supply from the power source to the load when an abnormality is detected in the load. It is.

[Background technology]

In general, in circuit breakers, movable contacts that are driven to open and close by operating the handle, or movable materials such as bimetals that are bent by the applied current so that the movable contacts are forcibly driven to open in the event of an abnormal current, are used to ensure smooth operation. In order to do this, the conductive braided wires are connected to form a current carrying path for the load current.

For example, in the circuit breaker disclosed in Japanese Unexamined Patent Publication No. 56-19841, a conductive braided wire is connected between the bimetal and the terminal board to smooth the operation of the bimetal.
In the circuit breaker of Japanese Utility Model Application Publication No. 161752, a conductive braided wire is connected between the movable contact and the relay terminal plate to smooth the operation of the movable contact. In this case, a conductive braided wire is connected between the bimetal and the movable contact to smooth the operation of both the movable contact and the bimetal.

However, in the above-mentioned circuit breakers, when the carrying current increases, it is necessary to use braided wire with a relatively large cross-sectional area, and the flexibility of the braided wire, so-called bending, deteriorates, and movable contacts and bimetallic This obstructs the movement of movable materials such as metals, etc., and becomes a factor that changes the characteristics of circuit breakers.

Therefore, it was considered that instead of using one thick braided wire, two thin braided wires were arranged in parallel to make the braided wire flexible and not affect the movement of the movable member.

However, when connecting two braided wires to a movable member, for example, if the movable member is a movable contact, a location with small displacement is selected to reduce the possibility of disconnection; for example, if the movable member is a bimetal, the connection Since the bending characteristics change depending on the part, there are limited locations, and the connection positions of the braided wires to the movable material are limited and narrow locations, so the two braided wires are stacked one on top of the other. It was decided that it would be done.

Therefore, the configuration shown in FIGS. 11 and 12 can be considered as a structure in which two braided wires are stacked one above the other and connected.

In the figure, reference numeral 6 denotes a movable contact, which has a movable contact 8 facing the fixed contact fixed to its tip, and is moved by operating a handle to open and close the movable contact 8 and the fixed contact. Further, reference numeral 15 is a bimetal, which bends when it senses that the load current is an abnormal current such as an overcurrent, and forcibly separates the movable contact 8 from the fixed contact via an abnormality detection mechanism.

Reference numerals 16 and 16 are two braided wires made of copper wire, and the movable members of the bimetal 15 and the movable contact 6 are connected in parallel to form a load current path.
The movable members and the connecting portions at the ends of these braided wires 16, 16 are welded to each other in the same upper and lower order.

The ends of the braided wires 16, 16 are welded in the same upper and lower order, as shown in FIG. 12 showing the actual arrangement, so the two braided wires 16 , 16 have approximately the same length, then
The braided wire 16 on one side is attached to the lower side at the connection part, and the distance between the connection parts is longer, so the slack in the center part becomes larger, whereas the braided wire 16 on the other side, which is overlapped on the upper side, is attached to the connection part. Since the distance between the parts becomes shorter, the slack in the center becomes smaller.

Therefore, as shown in the dashed line in Figure 12,
When the movable contact 6 performs a swinging motion, the upper braided wire 16 shown in the figure with a large amount of slack comes into contact with the lower braided wire 16 with a small amount of slack at the center and separates, causing the movable contact This may obstruct the movement of 6 or give unnecessary force to bimetal 15. Incidentally, a similar situation occurs when the bimetal 15 is curved.

In order to solve this problem, these two braided wires 16,
Although it is possible to reduce the contact at the center by separating the central portions of the wires 16, it is possible to reduce the contact in the central portions. The central parts of the two are close together.

Furthermore, by making the lengths of the two braided wires 16, 16 different in advance, it is possible to reduce the inhibition of the movement of the movable material due to contact between the central portions of the braided wires 16, 16, but this becomes complicated as the number of products increases. .

Furthermore, it is possible to adjust the length by twisting the braided wire 16 with a large amount of slack into a braided wire 16 with a small amount of slack, but this increases the rigidity of the braided wire 16 as a whole.

[Purpose of the invention]

The present invention has been provided in view of the above-mentioned points, and by attaching both ends of at least two or more braided wires upside down, the movement of the movable member is obstructed and unnecessary. The purpose of this invention is to provide a circuit breaker that is less likely to cause excessive force.

[Disclosure of the invention]

Hereinafter, the configuration of the present invention will be explained based on illustrated embodiments.

FIG. 1 shows the external appearance of a circuit breaker according to an embodiment of the present invention. As shown in the figure, a circuit breaker main body 1 has a pair of casings 2 ₁ and 2 ₂ connected by screws or caulking. The circuit breaker body 1 is configured by being fixed with a fixture 3 such as a rivet, and a handle 4 for opening and closing the circuit is provided protruding from the upper surface of the circuit breaker body 1.

Figure 2 shows the state in which the fixing fittings 3 have been removed and one casing 2 ₁ has been removed from the other casing 2 ₂ , and as shown in the figure, both casings 2
Various parts such as a pair of external connection terminals 5 ₁ and 5 ₂ , a movable contactor 6, and an arc extinguisher 7 are housed between terminals ₁ and 2 ₂ .

Figures 3 and 4 individually show the components required for the operation of the circuit breaker, and
Figures 8 through 8 show the cross-sectional structure of the circuit breaker.

In each of the above figures, 8 is a movable contact attached to the tip of the movable contact 6, and one terminal plate 9 ₁
The main circuit can be opened and closed by contacting and releasing a fixed contact 10 attached to the main circuit.

A tightening screw 13 is attached to each terminal plate 9 ₁ , 9 ₂ via a washer 11 and a spring washer 12 .
₁ , 5 ₂ are configured.

The engagement hole 15a of the bimetal 15 for overcurrent detection is inserted into the protruding piece 14 protruding from the terminal plate ₉₂ , and the protruding piece 14 is caulked, thereby fixing the bimetal 15 to the terminal plate ₉₂ . It's becoming like that.

One end of the braided wire 16 is welded to the free end side of the bimetal 15, and the other end of the braided wire 16 is welded to the movable contact 6. The braided wire 16 is connected to the bimetal 15 and the movable contact 6 as follows.

That is, as shown in FIG.
5 and movable contactor 6, etc., have two wires of the same length.
Braided wires 16a and 16b made of copper wires are connected in parallel configuration. In other words, the two braided wires 16a, 1
6b is bridge-linked between the bimetal 15 and the movable contact 6 in a substantially parallel manner, and on the bimetal 15 side, one end of the braided wire 16a is brought into direct contact with the plane of the bimetal 15, and the other braided wire 16b is One end is placed over the braided wire 16a and connected to the bimetal 15 by spot welding. In addition, on the movable contact 6 side, the braided wire 16b is directly attached to the plane from the end of the movable contact 6, and the other braided wire 16
Place a on top of the braided wire 16b with a slight shift,
They are each connected to the movable contact 6 by spot welding.

In addition, on the bimetal 15 side, the braided wires 16a, 16
Since the characteristics change depending on the position where b is connected, the two braided wires 16a and 16b are placed and attached one on top of the other, but on the movable contact 6 side, the two braided wires 16
In order to prevent the wires 16a and 16b from coming off, a part of the braided wire 16a located above is attached with a slight offset and is brought into contact with the movable contact 6 to improve the bonding force.

In this way, the movable contact 6 side is connected to the bimetal 1
Since the two braided wires 16a and 16b were installed with their ends upside down, the lengths of the two braided wires 16a and 16b are approximately the same as shown in FIG. 10. As a result, the slack in the central portions of the two braided wires 16a, 16b is approximately the same, and the slack in the mutual braided wires 16a, 16b with respect to the movement of the movable contact 6 and the bimetal 15 also follows the movement of the two braided wires 16a, 16b. For example, due to the movement of the movable contact 6 and the bimetal 15, the contact on one side with more slack, which was caused by connecting both ends of the conventional braided wire in the same upper and lower order, has decreased. The braided wire comes into contact with the braided wire on the side with less slack, which limits the deflection of the braided wire with greater slack, and reduces the problem of applying unnecessary force to the braided wire with less slack.

As a result, the resistance that prevents the movement of the movable contact 6 is reduced, ensuring smooth operation of the movable contact 6, and also avoiding unnecessary force being applied to the bimetal 15.

In this embodiment, since the two braided wires 16a and 16b are stacked and attached on the bimetal 15 side, the bonding strength is weaker than on the movable contact 6 side. 16a, 16b bimetal 1
By setting an angle in the direction in which the braided wires are led out from the joint part on the 5th side, contact between the two braided wires 16a and 16b at areas other than the welding area is reduced, and spot welding can be performed intensively at the welding area. In this way, we are working to further improve the bonding force.

Further, in one embodiment, two braided wires 16a, 16
b, like the movable contact 6 and the bimetal 15,
Although the electrical connection is made between the movable members that both move, as shown in the prior art, the connection may be between the movable contactor 6 and the fixed terminal plate, or the connection between the bimetal 15 and the fixed terminal plate. . The present invention is directed to a wire in which one or both of the two conductive members connected to both ends of at least two or more conductive braided wires is a movable member such as the movable contact 6 or the bimetal 15.

Furthermore, in one embodiment, two braided wires 16a, 1
6b, but in the case of three or more braided wires, similarly, when the above-mentioned braided wires are stacked at the connection point of one conductive member, the connection point of the other conductive member is stacked. By attaching the stacks of braided wire upside down in order, it is possible to similarly avoid interfering with the movement of the movable member or applying unnecessary force.

The movable contactor 6 is caulked to a movable arm 17, and the movable arm 17 is adapted to be fitted into a bottom opening 18a of a movable frame 18.
Reference numeral 19 denotes a rotating shaft for supporting the handle 4, the movable arm 17, and the movable frame 18, and the central portion 19a of the rotating shaft 19 is bent into a substantially U-shape and is inserted into the groove 4a in the handle 4. They are designed to fit together. Further, both ends 19b of the rotating shaft 19 are fitted into a U-shaped groove 20 that serves as a fulcrum of the movable arm 17, and are also fitted into a shaft support hole 21 and a U-shaped groove 22 of the movable frame 18. It's becoming like that.

23 is a tension spring for biasing the handle 4 to the on position and the off position. This tension spring 2
3 is engaged with the central portion 19a of the rotating shaft 19, and the other end is engaged with the shaft hole 2 of the movable arm 17.
It is engaged with a pin 25 whose both ends are supported by 4. Therefore, as shown in FIGS. 5 and 7, the handle 4 is biased toward the on position or the off position with the point where the tension spring 23 crosses the rotation center P of the rotating shaft 19 as a mirror. There is. Further, the movable arm 17, the movable frame 18, and the rotating shaft 19 can be integrated by the tensile force of the tension spring 23.

A protruding part 26 is formed at one end of the movable frame 18, and a handle 4 is attached to this protruding part 26.
The recessed groove 4b of the circuit breaker can be engaged as shown in FIG. 3, thereby preventing the handle 4 from popping out in the direction shown by arrow A during the assembly process of the circuit breaker. It is a familiar thing.

Next, reference numeral 27 is a compression coil type spring for forcibly opening the movable contactor 6 during a trip operation, and the tip end 27a of this spring 27 is connected to the spring of the movable frame 18 via a protection plate 28 for preventing arcing. It is adapted to be inserted into and engaged with an engagement hole 29 provided in the seat 31.

This spring 27 is connected to both casings 2 ₁ and 2 ₂
It is stored in the storage space 30 of, and its deep bottom surface 30a
The rear end 27b of the spring 27 is brought into contact with the rear end 27b of the spring 27. The arc protection plate 28 is
This is to prevent the spring 27 from being melted and damaged by the arc generated when the movable contact 8 of the movable contact 6 separates from the fixed contact 10 of the terminal plate ₉₁ , and the front protection plate 28a and the side It is composed of a protection plate 28b. Further, the front protection plate 28a is provided with a fitting hole 28c into which the tip end 27a of the spring 27 is fitted. This front protection plate 2
8a and the spring receiving seat 31 of the engagement hole 29 of the movable frame 18 are formed to be slightly inclined in order to improve contact with the spring 27.

Reference numeral 32 denotes a yoke plate for short-circuit current detection formed of a magnetic material, and side projecting pieces 33 projecting from this yoke plate 32 are formed on the pair of casings 2 ₁ and 2 _{2 ,} respectively. It is designed to be fixed by an engaging hole 34 which is provided with a cylindrical shape. The center piece 35 of the yoke plate 32 is caulked and fixed to the terminal plate 9 ₂ , and side pieces 36 forming magnetic paths extend vertically from both sides of the center piece 35 .

37 is a latch plate, and both ends of the pivot pin 39 inserted into the pivot hole 38 are connected to both the casings 2 ₁ ,
The latch plate 3 is supported by the engagement hole 40 of 2 ₂ .
7 is rotatable. This latch plate 37 is made of a magnetic material, and the magnetic flux generated around the bimetal 15 is transferred to the central piece 35 of the yoke plate 32.
The side piece 36 flows to attract the magnetic attraction piece 41 of the latch plate 37 to the side piece 36. Further, a contact piece 42 is formed at the upper end of the latch plate 37 and is adapted to come into contact with the free end side of the bimetal 15.

A locking step 44 is formed at the tip of both side pieces 43 of the latch plate 37, and the movable frame 18
It comes into contact with the locking part 45 of.

46 is a torsion spring that presses the contact piece 42 of the latch plate 37 toward the free end side of the bimetal 15;
As shown in FIGS. 5 and 7, this one end abuts against the back side of the abutment piece 42 of the latch plate 37, and the other end abuts against the handle 4 when the handle 4 is in the off position, and when the handle 4 is in the on position. When in position, it abuts against the casings 2 ₁ , 2 ₂ , and the handle 4
The force applied to the latch plate 37 is changed depending on the state. The torsion spring 46 is pivoted by being fitted into the pivot boss 47 ₁ of the casing 2 ₁ on the one hand, and received by the pivot boss 47 ₂ of the casing 2 ₂ on the other hand. Both casings 2 ₁ ,
2 ₂ also includes a shaft support hole 48 for supporting both ends 19b of the rotating shaft 19, a hole 49 for fitting the fixture 3, and an exhaust hole 50a for exhausting gas generated when the circuit is interrupted. , 50b, etc. are provided.

Furthermore, 7 is an arc extinguishing device, which is formed by holding a plurality of arc extinguishing plates 51 made of magnetic material at appropriate intervals with side plates 52 made of insulating material, and is connected to the movable contact 8. The arc generated when the fixed contact 10 is opened can be extinguished as quickly as possible. Each arc-extinguishing plate 51 is provided with a notch 51a so that the movable contact 6 can pass therethrough. A substantially V-shaped groove 51b is formed at the lower end of the notch 51a.
The gas accumulated around the contact is removed from the fixed contact 10 through
The shutoff performance can be improved by discharging the gas into a gas retention section 53 formed at the rear.

Further, an arc extinguishing chamber 54 that stores the arc extinguishing device 7,
A partition wall 56 is formed between the spring 27, the movable frame 18, etc., and the interrupting mechanism section 55 to prevent the arc from the arc extinguishing chamber 54 from entering the interrupting mechanism section 55. It is.

Next, the operation of this embodiment will be explained based on FIGS. 5 to 8.

First, FIG. 5 shows a state in which the circuit breaker is turned off, and in this state, the movable contact 8 and the fixed contact 10 are separated. At this time, the movable contact 6 is urged by the tensile force of the tension spring 23 and is separated to a position where it abuts the opening edge of the bottom opening 18a of the movable frame 18. Further, the handle 4 is similarly biased by the tensile force of the tension spring 23 and is stopped at a position where the groove 4b engages with the protrusion 26. Furthermore, since one end of the torsion spring 46 is pressed by the outer peripheral surface of the handle 4,
The other end of the torsion spring 46 strongly presses the back side of the abutment piece 42 of the latch plate 37. Therefore, the locking portion 45 of the movable frame 18 is reliably engaged with the locking step portion 44 of the latch plate 37. Further, due to this engagement, the spring 27 for tripping operation remains compressed in the storage location 30. Figure 6 shows the fifth
A sectional view taken along the line X-X in the figure is shown, and if you look at the figure, you can see that the central part 19a of the rotating shaft 19 and the pin 2 of the movable arm 17 are
5 can be clearly seen being pulled together by the tension spring 23.

Next, FIG. 7 shows the state when the circuit breaker is on. In this state, the movable contact 6 is biased by the tensile force of the tension spring 23, and the movable contact 8 is pressed into contact with the fixed contact 10. The machine is stopped at the position where it will be. In addition, the handle 4 also has a tension spring 2.
3, the operating portion of the handle 4 is stopped at a position where it is in contact with the casings 2 ₁ and 2 ₂ . In this way, the direction in which the movable contactor 6 and the operating section of the handle 4 are biased is reversed at the point where the tension spring 23 crosses the rotation center P of the rotation shaft 19. . Therefore, when the circuit breaker is on, as shown in FIG. 7, one end of the torsion spring 46 is no longer pressed against the outer peripheral surface of the handle 4, so the other end of the torsion spring 46 is The pressing force is weaker than in the OFF state, and a desired force is applied to the contact piece 42.

Therefore, if the bimetal 15 deforms due to overcurrent and presses the contact piece 42, or if the yoke plate 3
2 is magnetized by the short-circuit current flowing through the bimetal 15 and attracts the magnetic attraction piece 41, the latch plate 37 rotates around the pivot pin 39, thereby engaging the latch plate 37. When the stop portion 44 and the locking portion 45 are disengaged, the spring 27 is expanded, and the movable frame 18 rotates about the rotation center P of the rotating shaft 19.

FIG. 8 shows a state in which such a tripping operation is performed. As shown in the figure, since the movable frame 18 is pressed by the spring 27 and rotates, the movable contact 6 is moved against the movable frame 18. It is pushed by the opening edge of the bottom opening 18a and is forcibly driven in the contact opening direction. Movable contact 6
When the huddle is opened by a predetermined distance, the movable arm 17 is further driven in the contact opening direction by the tensile force of the tension spring 23, and finally the movable arm 17 comes into contact with the pivot pin 39, and the movable arm 17 stops, and the huddle 4 is adapted to stop at a position where the groove 4b is engaged with the protrusion 26 of the movable frame 18. At this time, since the movable frame 18 is tilted, the operating portion of the handle 4 stops approximately at the center between the on position and the off position, indicating that a trip operation has been performed.

When such a tripping operation is performed, as shown in FIG. 5, unless the handle 4 is returned to the OFF position and the engagement between the locking step 44 and the locking part 45 is restored, the handle 4 will be kept in the ON position. It cannot be stopped on the side.

As will become clear from a comparison between FIG. 5 and FIG. 7, the opening width of the bottom opening 18a of the movable frame 18 is longer than the opening/closing stroke of the movable contact 6. When the trip operation is not performed such as in manual opening/closing operation, the movable contact 6
The spring 27, the movable frame 18 and the latch plate 3
It is not affected by a contact breaking mechanism like No. 7.

Furthermore, in this embodiment, since one end of the torsion spring 46 is separated from the handle 4, the contact piece 42 of the latch plate 37 is strongly pressed when it is off, so the handle 4 cannot be opened or closed manually. This can reduce the possibility that the engagement between the locking step portion 44 and the locking portion 45 will be disengaged due to actual vibration.

Incidentally, when the movable contact 8 and the fixed contact 10 are opened and the main circuit is interrupted, an arc is generated between the movable contact 8 and the fixed contact 10, but this arc is The arc is extinguished as quickly as possible by the plurality of arc extinguishing plates 51. As described above, the substantially V-shaped groove 51b is formed at the lower end of the notch 51a of the arc-extinguishing plate 51, and this groove 51b is arranged below the terminal plate ₉₁ as shown in FIG. It is set up. Therefore, the gas generated around the contact when the circuit is interrupted is quickly discharged to the gas retention portion 53 at the rear of the terminal plate 9 ₁ via the kerf 51b. Furthermore, since the gas discharged into the gas retention portion 58 is discharged from the exhaust hole 50a, the amount of arc ejected to the outside can be reduced. This exhaust hole 50
In addition to a, there is also an exhaust hole 50b on the opposite side of the arc extinguishing device 7.
is provided to enhance the effect of gas discharge from the arc extinguishing device 7 by discharging gas in both directions.

〔Effect of the invention〕

As described above, the present invention allows the ends of the braided wires attached to one conductive member to be stacked up and down while the ends of the braided wires attached to the other conductive member are stacked up and down. Since it was installed with the
The lengths of the two braided wires are approximately the same, the slack in the center portion is also approximately the same, and even if one of the two conductive members moves, the slack of the other braided wires will follow the movement. As a result, the contact between the central portions of the two braided wires is reduced, and, for example, when the two ends of the braided wire are connected in the same vertical order in the past, the contact between the central portions of the two braided wires is reduced. The braided wire on the side with more slack contacts the braided wire on the side with less slack, restricting the deflection of the braided wire with more slack, and applies unnecessary force to the braided wire with less slack, inhibiting the movement of the movable member. Problems can be reduced, and the resistance that prevents the movement of movable materials such as movable contacts and bimetals will be reduced, and if the movable material is a movable contact, smooth operation of the movable contact can be ensured. Furthermore, when the movable member is a bimetal, it is possible to avoid applying unnecessary force to the bimetal.

[Brief explanation of drawings]

Fig. 1 is a perspective view showing the external appearance of a circuit breaker according to an embodiment of the present invention, Fig. 2 is a perspective view of the same with both casings opened, and Figs. 3 and 4 are the components of the same. FIG. 5 is a cross-sectional view of the above circuit breaker in the off state, FIG. 6 is a cross-sectional view taken along the line X-X of the above, and FIG. 7 is a cross-sectional view of the above circuit breaker in the on state. Fig. 8 is a sectional view of the circuit breaker as above in a tripped state, Fig. 9 is a connection configuration diagram of the movable contactor as above and bimetal,
FIG. 0 is an explanatory diagram of the operation of the same braided wire as above, FIG. 11 is a configuration diagram of the conventional example, and FIG. 12 is an explanatory diagram of the operation of the conventional example. 4 is a handle, 6 is a movable contact, 8 is a movable contact, 10 is a fixed contact, 15 is a bimetal, and 16 is a braided wire.

Claims (1)

[Claims] 1 A movable contact that opens and closes at least one of two separated conductive members by operating a handle, or a movable member such as a bimetal that bends when a current is applied so that the movable contact is forcibly driven to open in the event of an abnormal current. The edges of at least two or more parallel cross-linked conductive braids are formed by forming connecting portions on the planes of the two conductive members that are substantially perpendicular to the movable direction of the conductive members. In a circuit breaker in which parts are stacked and attached to each other and a load current is passed between the two conductive members, the end part of the braided wire is stacked at the connection part of one of the conductive members. . A circuit breaker, wherein the stacked ends of the braided wire are attached to the connecting portion of the other conductive member upside down.