JPH0755798Y2 - Circuit breaker - Google Patents

Description

[Detailed description of the device]

[Industrial applications]

The present invention relates to an improvement in a circuit breaker such as a breaker for wiring, which prevents gas or arc from being ejected from an operation handle portion when a current is cut off.

[Prior art]

An example of a conventional circuit breaker for wiring will be described with reference to FIGS. 6 and 7. In FIG. 6, in a main body case composed of a cover 1 and a base 2, a blocking portion composed of a fixed contact 4 having a fixed contact 3 and a movable contact 6 having a movable contact 5, and an eraser surrounding the blocking portion. It is composed of an arc chamber 7, an opening / closing mechanism 8, a trip device 9, an operation handle 10 and the like, and the drawing shows a closed state of a circuit breaker for wiring. The opening / closing mechanism 8 is connected to the movable contact 6 by a shaft 11 and the shaft 12
Movable contact holder 13, which opens and closes around, latch 15 rotatably supported by shaft 14, movable contact holder 13
And a toggle link 18, which is connected to the latch 15 by shafts 16 and 17, respectively, and a handle lever 19, which rotates in the left-right direction in the drawing about a fulcrum not shown, which is substantially the center of the opening / closing mechanism 8.
The toggle link 18 is composed of an operating spring 21 and the like mounted between a connecting shaft 20 and a handle lever 19. The trip device 9 is a thermo-electromagnetic type, and has a bimetal 22, a movable iron piece 24 driven by a trip coil 23, a trip bar 25, a latch having one end engaged with the trip bar 25 and the other end engaged with a latch 15. It consists of a receiver 26 and the like. The operation handle 10 is attached so as to fit on the head of the handle lever 9, and the knob 10a is seen through the window 27a of the handle receiving portion 27 of the cover 1. The facing surfaces of the operation handle 10 and the handle receiving portion 27 are both formed in an arc shape. This arc is formed along the turning radius when the operation handle 10 rotates together with the handle lever 9, and the base portion 10b of the operation handle 10 extends over the rotation range of the operation handle 10 and the window 27a of the handle receiving portion 27. Is designed to be blocked. Now, in the circuit breaker configured as described above, when the operation handle 10 is rotated leftward from the closing position in the figure, the operation spring 21 moves to the left side beyond the line of action of the toggle link 18, and toggles. The link 18 is bent in an inverted shape in the figure, and the movable contact holder 13 rotates about the shaft 12 in the left direction in the figure to open the contact. When the trip device 9 operates during overload or short circuit, the latch receiver 26 and the latch 15 are disengaged, and the latch 15 rotates around the latch shaft 14 in the right direction in the drawing, and the stopper shaft 28 is rotated. Is locked. As a result, the operating spring 21 exceeds the line of action of the toggle link 18, so that the contacts are opened as in the case described above.

[Problems to be solved by the device]

FIG. 7 shows an enlarged view of the handle receiving portion 27 and the operation handle 10. In FIG. 7, the operating handle 10 moves along the entire length A of the window 27a of the handle receiving portion 27 with the opening and closing operations of the circuit breaker, while the operating handle 12 constantly opens the window 27a. The arcs of the facing surfaces 10c and 27b of the operation handle 10 and the handle receiving portion 27 are made to have the same radius. However, in order for the operating handle 10 to move smoothly, some play is required for the handle receiving portion 27, and the arcuate facing surfaces 10c of the operating handle 10 and the handle receiving portion 27 are
A gap B is provided between 27b as shown in FIG. However, since the inside of the circuit breaker communicates with the outside atmosphere through the gap B, in the case of a considerably large arc at the time of overload or short circuit interruption, the generated gas or flame may be ejected from the window 27a of the handle receiving portion 27. There was a risk of harming people and surrounding equipment. In addition, the gap B
Dust in the external atmosphere may enter the circuit breaker through the circuit breaker, and in a dusty installation environment, operation failure due to adhesion to the switching mechanism 8 part or contact failure due to entry between the contacts 3 and 5 may occur. It was This invention eliminates the gap between the operating handle and the handle receiving part to prevent gas and flame from spouting from the window of the handle receiving part and dust from entering the outside, and is safe and reliable. The purpose of the present invention is to provide a circuit breaker with high flexibility.

[Means for solving problems]

According to this invention, the operation handle fitted and attached to the head of the handle lever of the opening / closing mechanism is arranged inside the cover with the knob part looking through the window of the handle receiving part of the cover. In the circuit breaker in which the surfaces facing each other are both arcuate, a coil spring is inserted between the operating handle and the handle lever to press the operating handle against the handle receiving portion, and The operating handle has a hexagonal cross section, and the width dimension P on the major axis side and the width dimension R on the minor axis side have a relation of slightly P>Q> R with respect to the inner diameter Q of the coil spring, and the tip is An inclined columnar protrusion is provided, and the end of the coil spring is pressed into the columnar protrusion.

[Action]

According to this invention, since the operation handle is pressed against the handle receiving portion by the spring force, there is no gap between the two. Further, the columnar projections into which the ends of the coil springs are press-fitted have a hexagonal cross-sectional shape, and the width dimension P on the major diameter side and the width dimension R on the minor diameter side thereof.
Is slightly P>Q> R with respect to the inner diameter Q of the coil spring.
However, it is easy to press fit the coil spring into this columnar protrusion because it is not necessary to go over the protrusion for locking, etc., and the coil spring after press fitting should have a corner on the long diameter side of the hexagonal section. The column-shaped projection is elastically gripped by the end portion that is spread by the section, and is securely held by the operation handle.

【Example】

An embodiment of the present invention will be described below with reference to FIGS. It should be noted that the same or corresponding parts as those of the conventional configuration shown in FIGS. 3 and 4 show the operation handle 10, and the operation handle 10 is provided on the bottom of the operation handle 10 as will be described later.
Recesses on both sides for fitting and mounting on the head of
29 are provided. A circular recess 30 is further provided at the center of the top of the recess 29, and a columnar protrusion 31 is formed at the center of the recess 30. As shown in FIG. 4, the columnar protrusion 31 has a hexagonal cross-sectional shape such that the front and rear of a prism are sandwiched by triangular prisms, and the tip of the triangular prism portion is cut diagonally to form inclined surfaces 31a and 31a. (Fig. 3). The width dimension P on the long diameter side and the width dimension R on the small diameter side of the columnar protrusion 31 are set to have a relationship of slightly P>Q> R with respect to the inner diameter Q of the coil spring 32 shown in FIG. The coil spring 32 shown in FIG. 5 is attached to the columnar protrusion 31 as follows. That is, one end 32a of the coil spring 32 is applied to the inclined surfaces 31a, 31a of the columnar protrusion 31, and at least one turn of the one end 32a is fitted into the vertical portion 31b of the columnar protrusion 31 while rotating the coil spring 32. At this time, with respect to the inner diameter Q of the coil spring 32, the width dimension P of the vertical portion 31b on the major diameter side is slightly larger, and the width dimension R on the smaller diameter side R.
Since the coil spring 32 is slightly small, the end 32a of the coil spring 32, which is widened at the corner on the long diameter side of the vertical part 31b of the hexagonal cross section, has a vertical part.
31b is elastically gripped and securely held by the operation handle 10 (Fig. 2). Further, since the coil spring 32 is press-fitted into the columnar protrusion 31 by simply inserting it by using the inclined surfaces 31a, 31a as guides, it is more workable than the structure in which the latching protrusion is passed over and latched. Is easy. Operation handle with coil spring 32 attached as described above
As shown in FIG. 1, reference numeral 10 denotes a recess 2 with the other end 32b of the coil spring 32 pressed against the upper surface of the head of the handle lever 19.
9 is fitted on the head L bent portion 19a of the handle lever 19.
Recess 29 of operating handle 10 and head 19a of handle lever 19
Means that the operation handle 10 is loosely fitted to the handle lever 19 to such an extent that it can slide in its axial direction. After that, the cover 1 is attached from above the operation handle 10. In such a configuration, the coil spring 32 is the operating handle.
10 is pressed against the handle receiving portion 27, and the arcuate facing surface 10c,
27b Close up the gap between the two and eliminate the gap between them. This close contact is caused not only by the operation handle 10 being in a stationary state, but also when the operation handle 10 is opened and closed while receiving the spring force.
It is maintained by sliding on the facing surface 27b of the. As a result, the window 27a of the handle receiving portion 27 is closed by the operating handle 10.
As a result, it is completely closed at all times, and gas or flame jetting at the time of the shutoff operation and dust intrusion at all times are prevented. The coil spring 32 can have a wire diameter, the number of turns, and the like appropriately set according to the weight of the operation handle 10 and the size of the gap B (FIG. 7), and the friction force between the operation handle 10 and the handle receiving portion 27 can be set. If the spring force of the coil spring 32 is set so as to be equal to or less than the load that hinders the movement of the operation handle 10, the operation failure does not occur during the cutting operation.

[Effect of device]

In this invention, the coil spring is inserted between the operating handle and the handle receiving portion to press the operating handle against the handle receiving portion, so that the gap between the operating handle and the handle receiving portion is eliminated, and the handle It is possible to prevent the gas and flame from being ejected from the window of the receiving portion during the cutoff operation and the intrusion of dust at all times. Further, since the coil spring is elastically held by the columnar protrusion of the operation handle, it is easier to attach the coil spring to the operation handle as compared with a structure in which the protrusion for locking is passed over and latched. As a result, the assembly work of the operation handle is simplified.

[Brief description of drawings]

1 is a sectional view of an essential part of an embodiment of the present invention, FIG. 2 is a sectional view of an operating handle with a spring attached, FIG. 3 is a sectional view of the operating handle of FIG. 2, and FIG. FIG. 3 is a bottom view of FIG. 3, FIG. 5 is a perspective view of the spring of FIG. 2, FIG. 6 is a sectional view of a conventional circuit breaker, and FIG. 7 is an enlarged sectional view of an essential part of FIG. 1: cover, 8: opening / closing mechanism, 10: operating handle, 10a: knob of operating handle, 19: handle lever, 27: handle receiving portion, 27: window of handle receiving portion, 32: coil spring.

Claims (1)

[Scope of utility model registration request] 1. An operating handle fitted and attached to the head of a handle lever of an opening / closing mechanism is disposed inside the cover with a knob portion looking through a window of a handle receiving portion of the cover. In the circuit breaker, the receiving portions of which face to face each other are both formed in an arc shape, a coil spring is inserted between the operating handle and the handle lever, and the operating handle is pressed against the handle receiving portion. The operating handle has a hexagonal cross-section, and the width dimension P on the major diameter side and the width dimension R on the minor diameter side thereof have a relationship of slightly P>Q> R with respect to the inner diameter Q of the coil spring, and the tip end. A circuit breaker characterized in that an inclined columnar protrusion is provided, and the end of the coil spring is press-fitted into the columnar protrusion.