JPH0537391Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field] The present invention relates to a compact overcurrent circuit breaker with a simple structure.

[Background Art] This type of overcurrent circuit breaker proposed by the present inventors in Japanese Patent Application No. 120648/1980 has a sliding member A for driving a contact spring as shown in FIG. , a sliding rotating body 32 that presses the contact spring 31
and engages with the bimetal piece 33 to rotate the sliding rotating body 32.
The latch lever 34 that latches the sliding rotor 3
2 is supported by a shaft 35, and a push button part 36 is guided in the front and back direction.Since these parts were separate from each other, the structure still had the disadvantage of being complex and having a large number of parts.

[Purpose of the invention] The present invention aims to simplify the structure by integrating the separate parts mentioned above, and when the latch is released and trips due to overcurrent detection, the repulsive force of the contact spring is used to prevent the latch from tripping. It is an object of the present invention to provide an overcurrent circuit breaker of this type that can prevent the sliding rotating body from jumping up and smoothly guide the sliding rotating body to a reset standby position.

[Disclosure of the invention] The overcurrent circuit breaker according to the invention has a long hole in the middle of the sliding body whose rear end serves as a push button that can freely protrude outside the case, and a horizontal shaft inserted through the long hole. The sliding body is pivotally supported so that it can slide back and forth and move up and down, and a spring is provided to bias the sliding body backward, and a contact plate whose rear end is fixed to the case and biased forward and upward by the spring is provided. Disposed below the sliding body,
As the sliding body moves forward, it pushes the front end of the contact plate downward to close the contact provided on the lower surface of the front end of the contact plate and the contact fixed to the case, and when both contacts are closed, the sliding It engages with a locking protrusion protruding from the tip of a bimetal piece disposed in a vertical plane parallel to the moving body, and locks the sliding body from upward rotation due to the reaction force from the contact plate and backward return due to the spring. A convex step is provided on the upper surface of the front end of the sliding body, and when the locking protrusion releases its engagement with the convex step due to the bending of the bimetal piece due to overcurrent and the two contacts open, the spring force from the contact plate is released. A concave step is provided on the upper surface of the front end of the sliding body near the bimetallic part, which contacts the locking protrusion so that the sliding body slides backward while restricting the upward movement of the front end of the sliding body. By giving the sliding body itself the freedom to slide back and forth and rotate up and down using the horizontal shaft and long hole, the push button part and the sliding rotating body in the conventional example can be integrated, and the plate surface of the bimetal piece can be slid. By arranging the bimetal piece parallel to the rotating surface of the moving body, the latch load is stabilized by preventing the bimetal piece from being affected by the rotational force of the contact spring, thereby eliminating the latch lever in the conventional example and eliminating the need for the recessed step. It is characterized in that it prevents the sliding body from jumping up due to the elastic force of the contact plate when tripping, and functions as a guide when the sliding body returns to the rear.

[Embodiment] FIGS. 1 to 3 show an embodiment of the present invention, in which the rear end of the sliding body 1 is a push button portion 1a that can be pressed from outside the case 5. A long hole 2 is provided in the middle of the moving body 1, and the sliding body 1 is pivotally supported by a horizontal shaft 3 inserted through the long hole 2 so as to be freely slidable back and forth and vertically. Fig. 1 shows the latched state in which the push button part 1a is pushed into the case 5 against the spring 4 that urges the sliding body 1 backward, and the contact spring 6 as a contact plate whose front side is tilted upward is shown in the latched state. The contact spring 6 is disposed below the sliding body 1 and is pressed downward as the sliding body 1 moves forward to close the contacts 13 and 14. The upward rotation caused by the force and the backward return caused by the spring 4 are locked by a locking protrusion 8 provided at the tip of the bimetal piece 7. The bimetal piece 7 is disposed in a vertical plane parallel to the sliding body 1, and its plate surface is parallel to the rotating surface of the sliding body 1, and the locking protrusion 8 is caused by thermal deformation of the bimetal piece 7 due to overcurrent. When the slider 1 retreats to the side, the sliding body 1 is released from the engaged state with the locking protrusion 8, that is, the latched state, rotates upward and slides backward, and shifts to the trip state shown in FIG.
The contact spring 6 is designed to return to its original state.

In FIG. 2, the support fittings 9 have mounting holes 9a, 9.
The rear end of the contact spring 6 is fixed to the contact spring fixing piece 9c, the rear end of the bimetal piece 7 is fixed to the bimetal fixing piece 9d, and the spring is fixed to the spring retaining piece 9e. One end of 4 is attached. The other end of the spring 4 is engaged with a spring engaging pin 10 that projects from the side surface of the sliding body 1, and biases the sliding body 1 diagonally downward. The card portion 11 is brought into elastic contact with the upper surface of the contact spring 6.

FIG. 3 shows the tripped state, in which the protrusion 12 provided on the upper surface of the tip of the slider 1 disengages from the locking protrusion 8 of the bimetal piece 7, so the slider 1 It rotates upward due to the elastic force of the contact spring 6, and moves backward due to the restoring force of the spring 4. At the beginning of this backward movement, the sliding body 1 is rotated upwardly by the large elastic force from the contact spring 6, but the locking protrusion 8
5 prevents the sliding body 1 from jumping up, and at the same time, the sliding body 1 is guided by the sliding contact between the locking protrusion 8 and the recessed step 15, and the sliding body 1 is The tip of the bimetallic piece 7 is guided under the locking protrusion 8, while the bimetallic piece 7 is cooled due to the interruption of the overcurrent, so that the locking protrusion 8 is brought under the tip of the slider 1. It returns to the above position and enters the reset standby state. Therefore, when the push button part 1a is pushed in from this state, the locking protrusion 8 comes into sliding contact with the slope 1b on the upper surface of the tip of the slider 1, climbs over the convex step part 12, latches the slider 1, and then slides again. The push button portion 1a at the rear end of the moving body 1 projects outward from the case 5 and is set in the state shown in FIG. 1a.

In addition, in the latched state shown in Figure 1a, the spring 4
The return of the sliding body 1 to the rear by the contact spring 6 and the upward rotation of the sliding body 1 by the contact spring 6 are stopped by the engagement between the locking protrusion 8 and the convex stepped portion 12. Even if the push button portion 1a is prevented from protruding out of the case 5 by some obstacle, the circuit is cut off by a trip, which is a so-called trip-free structure. In other words, the bimetallic piece 7 is heated by the overcurrent, and as shown in FIG.
When the locking protrusion 8 is bent in the direction of the arrow in FIG. As shown, the contact spring 6 returns and the contacts 13,1
4, thereby interrupting the circuit. Note that the rotation angle of the sliding body 1 at this time is regulated by the engagement between the recessed step 15 on the side surface of the tip end of the sliding body 1 and the locking protrusion 8 .

In addition, as shown in FIGS. 1b and 2, in order to make the sliding body 1 adjacent to the bimetal piece 7, the heater 16 is placed so that the bimetal piece 7 and the indirect heater (resistor) 16 do not come into contact with each other. is disposed in a through hole 17 provided in the bimetal piece 7, and both ends thereof are connected to a terminal plate 18 and a support fitting 9, respectively. In addition, the terminal plate 18 and the fixed contact 1
Each end of the terminal plate 19 provided with the terminal plate 4 protrudes from the front surface of the case 5 and serves as a plug.

FIG. 5 shows the structure of the card part 11 protruding from the lower surface of the sliding body 1. A protrusion 20 is provided at the center of the semi-cylindrical card part 11, and this protrusion 20 is connected to the contact spring 6. By inserting the slide body 1 into a guide groove 21 provided in the slide body 1, horizontal rotation of the slide body 1 is restricted. Note that the guide groove 21 is formed so that the width of the introduction part 21a at the rear part is slightly wider. Furthermore, the boundary between the upper surface of the slider 1 and the above-mentioned recessed step 15 is located just above the width of the protrusion 20, so that the contact spring is applied to the slider 1 before and after releasing the latch. The elastic force applied from 6 is balanced on the left and right sides, and the posture of the sliding body 1 is stabilized.

[Effect of the invention] In the above structure, the sliding body 1 is supported by the long hole 2 and the horizontal shaft 3 so that it can slide back and forth and move up and down. The movable rotating body 32 and the push button part 36 can be integrated, and by arranging the bimetallic piece 7 in a vertical plane parallel to the sliding body 1, the locking protrusion 8 provided at the tip of the bimetallic piece 7 can be Since the sliding body 1 is made to retreat laterally from the rotating surface of the sliding body 1, the spring force of the contact spring 6 applied to the bimetallic piece 7 through the sliding body 1 becomes parallel to the plate surface of the bimetallic piece 7. This hardly affects the operation of the bimetal piece 7,
Therefore, even if the latch lever 34 in the conventional example is omitted, the latch load can be stabilized, thereby reducing the number of parts and significantly simplifying the structure.

Further, the upward rotation of the sliding body 1 which is disengaged from the locking protrusion 8 due to the bending of the bimetal piece 7 due to an overcurrent is prevented by the recessed step 15 provided on the bimetal side of the upper surface of the sliding body 1 and the locking protrusion. 8, this concave stepped portion 15 is connected to the contact spring 6.
It prevents the sliding body 1 from jumping up due to the elastic force of the sliding body 1, and also functions as a guide when the sliding body 1 returns backward. is the locking protrusion 8
This has the advantage of being able to smoothly guide the user to the reset standby state located below.

[Brief explanation of the drawing]

FIG. 1a is a side view showing an embodiment of the overcurrent breaker of the present invention, b is a plan sectional view of the same, FIG. 2 is an exploded perspective view of the same, and FIG. 3 is a side view showing the same trip state. FIG. 4 is a side view of the main part showing the trip-free state of the same as above, FIG. 5 is a perspective view of the main part of the same as above, and FIG.
The figure is a side view of a conventional example. 1...Sliding body, 1a...Push button part, 2...Long hole,
3...Horizontal shaft, 4...Spring, 5...Case, 6...Contact spring, 7...Bimetal piece, 8...
... Locking protrusion, 12 ... Convex step portion, 15 ... Concave step portion.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) A long hole is provided in the middle of a sliding body whose rear end is a push button that can freely protrude outside the case, and a horizontal shaft inserted into the long hole allows the sliding body to slide back and forth. The sliding body is pivoted so as to be movable up and down, and is provided with a spring that biases the sliding body backward, and a contact plate whose rear end is fixed to the case and is biased forward and upward by the spring is disposed below the sliding body. The front end of the contact plate is pushed downward by the advance of the sliding body, and the contact provided on the lower surface of the front end of the contact plate and the contact fixed to the case are closed, and the two contacts are closed. Sometimes, a bimetal piece placed in a vertical plane parallel to the sliding body engages with a locking projection protruding from the tip, causing the sliding body to rotate upward due to the reaction force from the contact plate and return backward using a spring. A convex step for locking is provided on the upper surface of the front end of the sliding body, and when the locking protrusion releases its engagement with the convex step due to the bending of the bimetal piece due to an overcurrent and the gap between both contacts opens, the contact plate A recessed step is provided on the upper surface of the front end of the sliding body near the bimetallic part so as to make the sliding body slide rearward while restricting the upward movement of the front end of the sliding body due to the spring force. Overcurrent circuit breaker consisting of (2) By providing a protrusion in the center of the guard section protruding from the lower surface of the sliding body, and inserting the protrusion into the guide groove provided on the contact plate, the horizontal rotation of the sliding body can be regulated and The overcurrent circuit breaker according to claim 1, wherein the boundary between the upper surface of the sliding body and the recessed step is located above the width of the protrusion.