JPH088512Y2 - Circuit breaker trip device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to a trip device for a circuit breaker that automatically shuts off a circuit when an excessive current or an abnormal current flows in an electric circuit.

(Prior Art) A conventional circuit breaker trip device has a structure in which a bearing frame of a latch is covered from the outside of a frame and a shaft pin stretched on the frame is axially supported in a pin hole provided in the bearing frame. Things were common (for example, Japanese Utility Model Laid-Open No. 61-48638).

However, such a conventional structure has a problem in that the inner surface of the bearing frame is in contact with the outer surface of the frame, so that the latch operation is not smoothly performed and the tripping operation is delayed. However, there is a problem in that the hole core accuracy is poor because the distance between the pin holes becomes large due to the large width.

(Problems to be Solved by the Invention) The present invention solves the above-mentioned conventional problems and enables the latch to be operated smoothly, and further, the latch is downsized and the hole core accuracy is improved. It has been completed in order to provide a tripping device for a circuit breaker that can be used.

(Means for Solving the Problems) The present invention has been made to solve the above-mentioned problems, and includes a trigger lever actuated by an abnormal current detection mechanism (19), and an operation of the trigger lever. In a trip device for a circuit breaker consisting of a latch for releasing the cradle from the locked state with the trigger lever to perform a trip operation by releasing the cradle, in the trip device of the circuit breaker, a shaft pin is provided between frames arranged in parallel with the latch. A cradle of a gate-shaped bearing frame formed at a rear portion of the bearing that is pivotally supported and faces the cradle, and a locking pin for supporting the cradle is provided on the upper side of the base end that faces the upper plate portion of the cover. The bottom plate of the frame base and the cradle face the inner surface of the frame.The lower base end, which is the part that faces the inner surface of the frame, is located at the outside of the cradle. It is characterized by forming a claw that is pressed against the bottom surface of the cut-and-raised locking piece that faces the bottom plate of the base and resets the latch so that its tip contacts the inner surface of the frame. is there.

(Example) Next, the Example of this invention is described in detail based on drawing.

(1) is a synthetic resin base with a cover (2),
On the base (1), metal frames (3) and (3) connected by a girder rod (3a) are juxtaposed. (4) is a handle pivotally supported by the frame (3) and swinging left and right to be in an on, off, or trip state, and (5) is a movable contactor that opens and closes in conjunction with the handle (4). . The movable contactor (5) is pivotally supported by a pin (8) on an arm (7) provided integrally with the crossbar (6), and the lower end of the first link (9) is pivoted on the pin (8). Is supported,
Further, the lower end of the second link (11) is pivotally supported by a pin (10) on the upper end of the first link (9).
The upper end of the link (11) is pivotally supported by a cradle (14) described later with a pin (12) to form a link mechanism (13).

(14) is a cradle that is pivotally supported by a pin (15) between the frames (3) and (3) and also pivotally supports the upper end of the second link (11) by the pin (12) as described above.
The cradle (14) is a tension spring (16) stretched between a pin (10) and a locking part (4a) provided on the upper end of the handle (4).
Is always pulled upward by the first pin centered on the pin (15).
In the figure, it receives a counterclockwise rotational force. However, locking claws (2) formed by cutting and raising both ends of the front plate part (14a) of the cradle (14) on the side of the bearing frame (21) described later
4), the upper surface of (24) facing the cover (2) is supported by a locking pin (23) provided at a rear portion of a latch (17) described later, so that the latch (17) is engaged. When the handle is not removed, the cradle (14) has its tip held down as shown in Figs. 1 and 4, and the handle (4)
Can be turned on (FIG. 1) and turned off (FIG. 2).

Reference numeral (18) is a trip device that is operated by an abnormal current detection mechanism (19) that detects that an abnormal current has flowed through the circuit. The trip device (18) consists of a latch (17) and a trigger lever (20).
7) shows a gantry type bearing frame (21) formed in the rear portion of the cradle (14), which is provided below the bearing frame (21) by loosely fitting it between the frames (3) and (3). Pin holes (29),
(29) is pivotally supported by a shaft pin (22) which is stretched between the frames (3) and (3). Further, a locking pin (23) for supporting the cradle is provided on the upper side of the base end where the cradle (14) of the bearing frame (21) and the upper plate of the cover (2) are exposed. The pin (23) supports the locking claws (24) and (24) of the cradle (14).

Also, as shown in FIG. 5, the outside of the lower base end, which is a portion of the frame (3) facing the cradle (14) of the bottom plate portion of the base (1) of the bearing frame (21) and the inner side surface of the frame (3), is shown in FIG. When the cradle (14) is reset, the locking claws (24) and the claws (24) that are pressed against the lower end face of the base (1) of the base (1) are reset to reset the latch (17) ( 30),
The (30) is bent and formed so that its tip is in contact with the inner surfaces of the frames (3) and (3). Reference numeral (31) is the reset prevention piece of the latch (17) stretched on the rear end of the bearing frame (21), and as shown in FIG. 4, when the cradle (14) is in the trip state, It abuts below the front plate portion (14a) of (14) to prevent the latch (17) from being raised.

Further, in the latch (17), a flat plate-like locking piece (26) is formed by bending on the lower side of the tip of an arm plate (25) continuously provided on one side of the bearing frame (21). On the other hand, the trigger lever (20) has both ends thereof pivotally attached to both side walls of the base (1) and is provided with a trigger hook (28) which engages with a locking piece (26) of the latch (17). In this embodiment, the trigger hook (28)
Is provided with a corner portion (27) for receiving the end portion of the latching piece (26) of the latch (17), and this corner portion (27) has a horizontal portion (27a) and an obliquely upward facing portion. It is composed of an inclined portion (27b). Reference numeral (19) is an abnormal current detection mechanism for swinging the trigger lever (20) against the spring (32) in the direction of releasing the engagement between the trigger hook (28) and the locking piece (26). Is a bimetal type that presses the upper side of the strain trigger lever (20) by heat generation due to overcurrent.

(Operation) In the case of such a configuration, the latching piece (26) of the latch (17) is normally the trigger hook (2) of the trigger lever (20).
Although the whole tripping device is held at the position shown in Fig. 1 by engaging with 8), if an abnormal current flows in the circuit, the abnormal current detection mechanism (19) will start and pull out as shown in Fig. 4. The trigger lever (20) of the removing device (18) is rotated. This allows the trigger hook (28) and latch (1
The engagement with the locking piece (26) of 7) is released, and the latch (17)
The locking pin (23) provided on the rear part of the cradle (14) disengages from the locking claw (24) of the cradle (14), and the cradle (14) is rotated upward by the tension spring (16) around the pin (15). Opening the movable contactor (5) through the link mechanism (13) and setting the handle (4) in the trip state is similar to the conventional circuit breaker of this type.

However, according to the present invention, the gate type bearing frame (21) formed at the rear part of the latch (17) has a lower portion under the locking claws (24), (24) when the cradle (14) is reset. The claw (30), which is pressed against the end face and resets the latch (17)
The bearing frame (21) is narrower than the space between the frames (3) and (3) because the tip of the (30) is bent and formed so as to contact the inner surfaces of the frames (3) and (3). A shaft pin that supports the pin holes (29) and (29), because the distance between the pin holes (29) and (29) provided under the bearing frame (21) becomes shorter and the hole core accuracy becomes higher. The rotation with (22) becomes smooth. Moreover, since the bearing frame (21) comes into contact with the inner surfaces of the frames (3) and (3) only at the tips of the claws (30) and (30), the operation of the latch (17) is smooth and stable. Done. Therefore, the tripping operation of the circuit is promptly performed.

Furthermore, since the bearing frame (21) of the latch (17) has a narrow width, there is an advantage that the entire shape of the latch (17) can be downsized and material can be saved.

(Effects of the Invention) As is apparent from the above description, the present invention makes it possible to improve the accuracy of the pin core of the pin hole by making the bearing frame of the latch narrower than the frame, and to reduce the size of the latch. Since it is only the tip of the claw that causes contact with the frame, the operation is smooth and stable. Therefore, the present invention has an extremely great practical value in combination with the advantage that it can be provided at a low cost with a simple structure.

[Brief description of drawings]

FIG. 1 is a partially cutaway front view showing an embodiment of the present invention, FIG. 2 is a plan view of an essential part thereof, FIG. 3 is a perspective view of the essential part, and FIG. The front view and FIG. 5 are partially cutaway front views in the reset state. (1): Base, (3): Frame, (14): Cradle, (17): Latch, (19): Abnormal Current Detection Mechanism, (2
(0): Trigger lever, (21): Bearing frame, (22): Shaft pin, (23): Locking pin, (29): Pin hole, (30): Raising claw.

Claims (1)

[Scope of utility model registration request] 1. A trigger lever (20) actuated by an abnormal current detection mechanism (19) and a cradle (14) which is disengaged from engagement with the trigger lever (20) by actuation of the trigger lever (20). In a trip device for a circuit breaker, which comprises a latch (17) for releasing a stable state and performing a trip operation, a frame (3), (3) in which the latch (17) is juxtaposed to a base (1). It faces the cradle (14) of the gate-shaped bearing frame (21) and the upper plate part of the cover (2) formed in the rear part which is supported by the shaft pin (22) and faces the cradle (14). Frames (3), (3) facing the bottom plate portion of the base (1) of the bearing frame (21) and the cradle (14) while providing a locking pin (23) for supporting the cradle at a location above the base end. The cradle (14) is reset on the outside of the lower base end, which is the part facing the inner surface of the Bearing frame (21)
The front side of the front plate (14a) of the cradle (14) on the side is pressed forward against the lower end face of the locking piece (24), which is formed by cutting and raising the base plate (1) of the base (1). Claws (30), (30) which have been triggered to reset the latch (17)
Is formed so that its tip is in contact with the inner surfaces of the frames (3) and (3).