JP3843609B2 - Circuit breaker trip coil unit - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a trip coil unit for overcurrent tripping that is built in a circuit breaker intended for implementation, such as a circuit breaker for wiring, a circuit breaker, and the like.
[0002]
[Prior art]
Built in a circuit breaker, this electromagnetic overcurrent trip device has a main circuit terminal plate at one end of the coil conductor as a trip coil unit that detects overcurrent in the main circuit and trips the latch of the contact opening / closing mechanism. It consists of an assembly of an attached tripping coil, an oil dashpot inserted into the coil, an inverted L-shaped yoke, and an armature connected to the lower end side of the yoke, and corresponds to each pole of the circuit breaker The same structure as the present invention has a configuration in which the overcurrent tripping device is incorporated from the side into a room corresponding to each pole partitioned inside an open front type assembly unit case as a resin molded product. This is known from Japanese Patent Laid-Open No. 10-50195 proposed by the applicant.
[0003]
Here, the assembly structure of the proposed trip coil unit incorporated in the circuit breaker is shown in FIGS. 5 (a) and 5 (b), taking a circuit breaker for three phases (three poles) as an example. In the figure, 1 is an electromagnetic overcurrent tripping device, 2 is a unit case for assembly thereof, and three overcurrent tripping devices 1 corresponding to each pole of the circuit breaker are incorporated in this unit case 2. (B) The trip coil unit shown in the figure is assembled. Here, the overcurrent tripping device 1 includes a tripping coil 4 in which a main circuit terminal board (load side terminal board) 3 is soldered to one end of a coil conductor, and an oil dashpot fitted into the tripping coil 4. 5, an inverted L-shaped yoke 6 that forms a magnetic path for the tripping coil 4 , an armature 7 that is swingably assembled to the lower end side of the yoke 6, and its return spring 8. A through hole 6 b into which the top of the oil dash pot 5 is fitted is opened in the upper leg piece 6 a of the yoke 6. Note that a lower end portion of the oil dash pot 5 facing the armature 7 is provided with a flange portion 5a for fixing and supporting the oil dash pot to the unit case 2 as described later.
[0004]
On the other hand, the unit case 2 for assembly of the overcurrent trip device is made as a resin molded product, and there are three rooms corresponding to each pole with a partition wall in the box-shaped case with the front open. 2a is defined, and the left and right side walls of each room 2a have a yoke insertion groove 2b that supports the upper leg of the yoke 6, and a flange insertion groove 2c that supports the flange portion 5a of the oil dash pot 5. A circular notch engaging hole 2d for fitting the top of the oil dash pot 5 is formed in the case ceiling, and the overcurrent tripping device 1 is inserted into each room 2a one by one from the open end face (b ) Assemble the trip coil unit shown in the figure.
[0005]
The assembly procedure is performed as follows. First, the armature 7 and the return spring 8 are assembled to the yoke 6 in a step before the overcurrent tripping device 1 is assembled to the unit case 2. Next, the trip coil 4 and the yoke 6 are sequentially inserted into the oil dash pot 5 from above to tentatively assemble the trip device 1, and this temporary assembly is placed in front of the chamber 2 a of the case 2 (the open end face of the unit case). The protrusions that protrude from the left and right sides of the upper leg side of the yoke 6 during this insertion process are press-fitted into the insertion groove 2b and restrained and held in place, and the flange portion 5a of the oil dash pot 5 is inserted. Is pressed into the insertion groove 2c on the lower side and fixed in place.
[0006]
[Problems to be solved by the invention]
When a circuit breaker incorporating the above trip coil unit is manufactured, in order to obtain a stable product with no variation in its tripping operation characteristics, the trip coil is assembled in the assembled state of the overcurrent trip device 1. It is important that the oil dashpot 5 inserted into the armature 4 and the armature 7 of the yoke 6 facing the end face of the oil dashpot 5 are correctly supported at a predetermined assembly position. When the trip unit coil is assembled by an automatic assembly method using an assembly robot, etc., in addition to the simplest possible structure, in order to perform automatic assembly using a robot, the assembly robot can be operated from one direction. Therefore, an assembly structure is required in which each component of the tripping device can be stably assembled at a predetermined position in the unit case.
[0007]
In this respect, the conventional assembly structure described above has the following problems in performing automatic assembly by a robot.
(1) The assembly of the trip coil 4 and the oil dashpot 5 and the assembly of the yoke 6 and the armature 7 cannot be individually assembled into the unit case 2 from the same direction (front) by the assembly robot. In the previous step, the yoke 6 is inserted into the oil dash pot 5 from above and temporarily assembled, and this temporary assembly (the assembly between the oil dash pot 5 and the yoke 6 is loosely assembled) is inserted into the unit case 2. In this case, it is necessary to press-fit the oil dash pot 5 and the yoke 6 individually into the insertion grooves 2b and 2c of the unit case 2, which complicates the positioning operation of the assembly robot.
[0008]
(2) Even when each component of the tripping device 1 is press-fitted into the unit case 2, the inverted L-shaped yoke 6 inserted from the front into the unit case has its upper leg side 6a fitted into the insertion groove 2b on the case side. Although fixed and supported at the assembly position, the relative position between the armature 7 and the end face of the oil dashpot 5 is stabilized because there is no fixed support means for restraining and holding the lower leg piece with the armature attached at the assembly position. Therefore, the tripping operation characteristics for individual circuit breaker products tend to vary.
[0009]
The present invention has been considered in view of the above points, and is an improved trip coil unit in which components of an overcurrent tripping device can be easily and stably assembled into a predetermined position in the case with respect to the unit case for assembly. It is an object to provide an assembly structure.
[0010]
[Means for Solving the Problems]
In order to achieve the above object, according to the present invention, a trip coil unit incorporated in a circuit breaker, detects an overcurrent of a main circuit, and pulls off a latch of a contact opening / closing mechanism. A tripping device includes a tripping coil having a main circuit terminal plate attached to one end of a coil conductor, an oil dashpot fitted into the coil, an inverted L-shaped yoke, and an armature connected to the lower end side of the yoke In an assembly that is assembled by inserting the components of the overcurrent tripping device corresponding to each pole of the circuit breaker into the room corresponding to each pole partitioned inside the unit case for assembly from the open end face side The upper leg piece of the yoke is formed with a notch groove for inserting the top of the oil dash pot from the front, and an overcurrent trip device is inserted on the bottom side of each room of the unit case. State oil dash pot, and collectively hold the lower end portion of the yoke from the left and right is provided a support guide member for restraining held in assembled position, as the support guide member, left and right side walls each room with partitioned in the unit case A pair of left and right guide rails protruding in a T-shape from each other and lined face-to-face, a guide groove into which the collar portion of the oil dashpot is inserted from the front on the inner surface of the guide rail, and an oil dashpot retaining stopper at its front end With the oil dash pot press-fitted between the left and right guide rails, the previously incorporated yoke is clamped from the left and right at the rear ends of the guide rails (claim 1).
[0012]
In the above configuration, after inserting the yoke and armature assembly into the unit case from the front, and then inserting the oil dash pot into the trip coil and inserting it into the unit case from the front, the top of the oil dash pot is already in the case. The front end of a pair of left and right guide rails, which are provided on the bottom side of the unit case and project in a T shape from the left and right side walls, is fitted into the notch groove formed in the upper leg piece of the yoke incorporated in the oil dash pot. The lower leg piece of the yoke inserted earlier is sandwiched from the left and right by being deformed into a “C” shape so that the rear end of the guide rail is narrowed inward. As a result, the collar portion of the oil dashpot and the lower leg piece of the yoke previously inserted are collectively sandwiched between the pair of left and right guide rails and restrained and held at a predetermined assembly position. . In addition, the yoke and the oil dashpot can be inserted into the unit case from the same direction, and this can be applied to an automatic assembly method using an assembly robot.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below based on the examples shown in FIGS. In the drawings of the embodiment, the same members corresponding to those in FIG.
That is, in this embodiment, with respect to the assembly unit case 2 of the overcurrent tripping device 1, for each room 2a corresponding to each pole defined inside the case, the upper portion thereof is shown in FIG. A yoke insertion groove 2b similar to the structure and a circular notch engagement hole 2d for fitting the top of the oil dash pot 5 are formed, and further, a component of the overcurrent tripping device 1 on the bottom side in the room When the unit case 2 is molded, a support guide member 2e that holds the oil dash pot 5 and the yoke 6 together from the left and right and holds them in a predetermined assembly position is integrally formed. .
[0014]
The support guide member 2e protrudes in a T-shape from the left and right side walls of each room 2a partitioned inside the unit case 2 through rib-shaped protrusions 2e-1 as shown in FIG. 2 (c). A pair of left and right guide rails 2e-2 are formed. A guide groove 2e-3 for inserting and supporting the flange portion 5a of the oil dash pot 5 from the front is supported on the inner surface of the guide rail 2e-2, and a flange portion formed at the front end thereof. A retaining stopper 2e-4 of 5a is formed. Here, the distance L between the pair of left and right guide rails 2e-2 arranged facing each other is set to be slightly smaller than the outer diameter of the flange portion 5a of the oil dash pot 5. Further, the front-rear direction of the length of the guide rail 2e-2 has its rear end portion 2e-5 is set to a length such as to face the side edges of the yoke 6 Ru incorporated in the unit case 2. Further, in the upper leg piece 6a of the yoke 6, a U-shaped notch groove 6c into which the top portion of the oil dash pot 5 is fitted from the front is formed instead of the through hole 6a shown in FIG.
[0015]
Next, the procedure and operation for incorporating the overcurrent tripping device 1 into the unit case 2 having the above-described configuration will be described with reference to FIGS. 3 (a) to 3 (c).
First, the yoke 6 with the armature 7 and the return spring 8 attached to each room 2a of the unit case 2 is inserted from the front (the open end face side of the unit case 2) as shown by the arrow (1) in FIG. The protrusions protruding from the left and right sides of the upper leg side of the yoke 6 are press-fitted into the yoke insertion groove 2b. In this insertion process, the lower leg side of the yoke 6 passes between a pair of left and right guide rails 2e-2 formed on the bottom side of the unit case 2 and is inserted into the back thereof.
[0016]
Next, the oil dash pot 5 is inserted into the chamber 2a of the unit case 2 from the front as shown by the arrow (2) in FIG. In this insertion step, the top of the oil dash pot 5 is fitted into a notch groove 6 c formed in the upper leg piece of the yoke 6. Further, when the lower flange portion 5a is simultaneously pushed into the guide groove 2e-3 formed in the guide rail 2e-2 in this insertion step, the top portion of the oil dash pot 5 is fitted into the circular engagement hole 2d. At the same time, the flange portion 5a of the oil dashpot 5 and the yoke 6 previously assembled are sandwiched between the pair of left and right guide rails 2e-2 through the course of FIGS. 3 (a) to 3 (c). Become.
[0017]
That is, when the state shown in FIG. 3A is changed to the state shown in FIG. 3B, the guide rail 2e-2 is widened with the rib-like protrusion 2e-1 as a fulcrum and the front half is widened to the right and left by the flange 5a. The rear end 2e-5 of the rail 2e-2 moves inward, and the left and right guide rails have a “C” shape. (C) In the assembled state shown in the figure, the flange 5a is locked by a stopper 2e-4 formed at the front end of the guide rail 2e-2 so as not to come out of the assembly position, and the yoke 6 is fixed to the guide rail 2e-2. The rear end 2e-5 is clamped from the left and right and restrained and held at a predetermined assembly position. As a result, a stable relative positional relationship is established between the oil dashpot 5 and the armature 7 of the yoke 6 facing the oil dashpot 5. To do.
[0018]
【The invention's effect】
As described above, according to the configuration of the present invention, the guide in which the yoke and the oil dashpot are provided in the unit case in the assembly process of the trip coil unit in which the components of the overcurrent tripping device are inserted into the unit case. The pair of left and right support guide members are collectively restrained and held at a predetermined assembly position. As a result, the relative position between the oil dash pot 5 and the armature of the yoke facing the oil dash pot 5 is stably established, and the tripping operation characteristics of the circuit breaker are stabilized. Moreover, in the assembly process of the tripping device, each component of the overcurrent tripping device can be individually inserted and assembled into the unit case from the same direction, thereby enabling automatic assembly by operation of the assembly robot.
[Brief description of the drawings]
FIG. 1 is an assembly configuration diagram of a trip coil unit according to an embodiment of the present invention, in which FIG. (A) is a front view of a part of the case, (b) to (d) are a cross-sectional view taken along line AA, a cross-sectional view taken along line BB, and a top view of (a), respectively. 3 is an explanatory view of the assembly configuration of the trip coil unit shown in FIG. 1, wherein (a) to (c) are oil dashpots as seen from the top surface of the unit case and the cross-sectional position corresponding to FIG. 2 (c), respectively. FIG. 4 is an assembly configuration diagram of a trip coil unit corresponding to FIG. 1, (a) is a divided perspective view thereof, and (b) is an assembled perspective view thereof. FIG. 5 is a conventional circuit diagram. It is an assembly configuration diagram of the trip coil unit built in the circuit breaker, (a) is an exploded perspective view, (b) is an oblique view of the assembled state. View [Explanation of symbols]
1 Overcurrent trip device 2 Unit case 2a Room 2b Yoke insertion groove 2d Oil dash pot top engagement hole 2e Support guide member 2e-2 Guide rail 2e-3 Guide groove 2e-4 Stopper 2e-5 Rear end 3 Main Circuit terminal board 4 Trip coil 5 Oil dash pot 5a Eave part 6 Yoke 6a Upper leg part 6c Notch groove 7 Armature 8 Return spring

Claims (1)

A trip coil unit built in a circuit breaker that detects the overcurrent of the main circuit and trips the latch of the contactor switching mechanism. The electromagnetic overcurrent tripping device has a main circuit terminal plate at one end of the coil conductor. It consists of an assembly of a tripping coil with a lip, an oil dashpot fitted into the coil, an inverted L-shaped yoke, and an armature connected to the lower end of the yoke, and corresponds to each pole of the circuit breaker In the one assembled from the open end face side into the room corresponding to each pole partitioned inside the assembly unit case parts of the overcurrent trip device
In the upper leg piece of the yoke, a notch groove for inserting the top of the oil dash pot from the front is formed, and for each room of the unit case, an oil dash pot with an overcurrent tripping device inserted in the bottom side thereof, And a support guide member that holds the lower end of the yoke in a lump from the left and right and restrains and holds it at the assembly position. As the support guide member, each room partitioned in the unit case protrudes from the left and right side walls in a T-shape. A pair of left and right guide rails lined up facing each other, a guide groove for inserting the flange portion of the oil dash pot from the front on the inner surface of the guide rail, and an oil dash pot retaining stopper at the front end thereof are formed. With the press fit between the left and right guide rails, Trip coil unit of the circuit breaker being characterized in that so as to clamp at the rear end of Le.

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