JP2011018514A - Blocker - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a blocker which improves a mounting structure of a heat radiating fin so as to easily mount the heat radiating fins attached to respective contact pieces of a fixed contact after combining the contact pieces with a terminal board without using a fastening screw.SOLUTION: In the blocker composed of a pair of terminal boards arranged at both ends of a mounting base and connected with a main circuit, the fixed contact composed of a plurality of pairs of contact pieces arranged at a right side and a left side by being combined with the terminal boards, and a rotary bridge-connection type movable contact opposite to the fixed contact, heat radiating fins 8 are arranged on respective contact pieces 3A, 3B of the fixed contact as heat radiation promotion means. The heat radiating fins 8 are mounted to respective fixed contact pieces 3A, 3B with snap connection. Concretely, the heat radiating fin has a structure where connection pawls 8a are formed on the pointed heads of its legs 8a of the heat radiating fin 8 by bending a metal plate at a U-shape, and the connection pawls are snap-combined by being fit into a connection hole 3a formed at each end of the contact pieces 3A, 3B.

Description

  The present invention relates to a disconnector for a high-voltage circuit that is used by being mounted on a switchboard or the like.

  As the disconnector for the high voltage circuit described above, the fixed contact that faces the movable contact of the bridge contact is divided into multiple pairs of contact pieces arranged on the left and right, and this contact piece is used as the main circuit. A disconnector having a structure coupled to a terminal plate to be connected is known.

  In addition, since the upper limit of the temperature rise associated with Joule heat generation during energization is regulated by the standard for the contact portion of this disconnector, heat radiation of the movable contact is promoted by providing a heat radiation fin on the contact piece. Such a configuration has been proposed prior to the same applicant as the present invention (see Patent Document 1).

  Next, the conventional structure of the disconnector is shown in FIGS. 3 (a) and 3 (b). In the figure, 1 is a mounting base for a disconnector, 1a is an insulating support frame provided on the mounting base 1, 2A and 2B are arranged at both ends of the support frame 1a, and main circuits (bar conductors on the power supply side and load side). 3 is a fixed contact attached to the terminal plates 2A and 2B, 4 is a contact holder for the fixed contacts 2A and 2B, 5 is a rotary bridge movable contact, and 6 is a movable contact. An open / close shaft (rotary shaft) connected to 5 and an operation lever 7 connected to the open / close shaft 6.

  Here, the fixed contact 3 is composed of a plurality of pairs of contact pieces 3A and 3B arranged in parallel along the width direction (left and right direction) of the terminal plates 2A and 2B, and each contact piece 3A and 3B is a contact holder. 4 is connected to the terminal plates 2A and 2B. Moreover, the radiation piece 8 (2 sheets) is attached to the contact piece 3A, 3B for every contact piece. The heat dissipating fins 8 are metal plates having good heat conductivity, and their leg portions are distributed and overlapped on both sides of the end portions of the contact pieces 3A and 3B, and then fastened by two fixing screws 9 to be connected to the contact pieces. Combined heat transfer.

The movable contact 5 is an oval conductor (copper) block having a length corresponding to the width of the fixed contacts 3A and 3B. The movable contact 5 is arranged between the fixed contact pieces 3A and 3B and is connected to the opening / closing shaft 6. It is connected.
The disconnector having the above-described configuration is installed in the switchboard, and its terminal plates 2A and 2B are connected to the main circuit (power supply side, load side conductor bar) of the distribution system. When the disconnecting switch is inserted by operating the operation lever 7, the bridge-shaped movable contact 5 is brought into contact between the contact pieces 3 </ b> A and 3 </ b> B of the fixed contact 3. When the operating lever 7 is operated to the disconnection position from this closed state, the movable contact 5 rotates 90 ° about the opening / closing shaft 6 and is separated from the contact pieces 3A and 3B of the fixed contact, thereby disconnecting the main circuit. . Further, Joule heat generated in the contact pieces 3A and 3B of the fixed contact 3 due to energization is transferred to the radiating fins 8 and radiated to the surroundings.

JP 2006-100026 A

  By the way, the conventional structure of the disconnector described above has the following problems in its assemblability. That is, the number of contact pieces 3A and 3B of the fixed contact 3 varies depending on the current carrying capacity of the disconnector. For example, in a disconnector having a rated current of 3000A or 4000A class, the number of contact pieces 3A and 3B is 20 pieces. For this reason, a total of 40 screw tightening operations are required to attach two radiating fins 8 to each of the contact pieces 3A and 3B, and the assembly work requires a lot of man-hours and time. Production costs are high. In addition, there are restrictions on the procedure of the assembly process, and it is necessary to attach the radiating fin 8 before the contact pieces 3A and 3B are assembled to the terminal plates 2A and 2B, and the contact pieces 3A and 3B are connected to the terminals. After assembling the plates 2A and 2B, it is not easy to replace the heat dissipating fins 8.

  The present invention has been made in view of the above points, and the heat dissipating fins attached to each contact piece of the fixed contact can be easily performed without using a fixing screw and after the contact piece is coupled to the terminal plate. It is an object of the present invention to provide a disconnector having an improved mounting structure for heat dissipating fins.

In order to achieve the above object, according to the present invention, a pair of terminal plates arranged at both ends of the mounting base and connected to the main circuit, and a plurality of pairs of contact pieces coupled to the terminal plates and arranged on the left and right And a rotary bridge movable contact that faces the fixed contact. The disconnector is provided with a radiating fin for each contact piece as a heat radiation promoting means. In
The heat dissipating fin is attached to the fixed contact piece by snap coupling (Claim 1). Specifically, the heat dissipating fin bends the metal plate in a U-shape, and the engaging claw is attached to the leg tip. The engaging claw is inserted into an engaging hole formed at the end of the contact piece and is snap-coupled (Claim 2).

  According to said structure, a radiation fin can be easily mounted | worn with the contact piece of a stationary contact by a screwless system. In addition, the mounting of the heat dissipating fins can be performed without any trouble in operation even at the assembly stage after the contact pieces are arranged on the left and right and assembled to the terminal board, and the degree of freedom in the assembly process is increased.

BRIEF DESCRIPTION OF THE DRAWINGS It is a structural diagram of the state which attached the radiation fin by the Example of this invention to the contact piece of a stationary contact, (a) is a side view, (b) is a front view of a partial cross section. FIG. 2 is an exploded view of FIG. 1, in which (a) is a side view of a cross section of a main part of a contact piece, (b) is a side view of a heat radiating fin, and (c) is a front view of (b). It is a conventional structure figure of the whole disconnector used as the object of this invention, (a) is a top view and (b) is a side view.

Embodiments of the present invention will be described below based on the examples shown in FIGS. In addition, in the figure of an Example, the same code | symbol is attached | subjected to the member corresponding to FIG. 3, and the description is abbreviate | omitted.
That is, in the conventional structure shown in FIG. 3, the radiating fins 8 attached to the contact pieces 3 </ b> A and 3 </ b> B of the fixed contact 3 are fixed to the contact pieces 3 </ b> A and 3 </ b> B via the fixing screws 9. In this embodiment, the heat dissipating fins 8 are configured as follows without using screws, and are snap-coupled to the end portions of the contact pieces 3A and 3B.

  First, as shown in FIGS. 2B and 2C, the heat dissipating fin 8 has a narrow width extending downward from both ends thereof after folding a good heat conducting metal plate in two and bending it into a U shape. An engaging claw 8b for preventing the hook 8b from being bent outwardly is bent at the tip of the leg 8a. On the other hand, at the upper ends of the contact pieces 3A and 3B, as shown in FIG. 2A, there are formed engagement holes 3a into which the leg portions 8a of the radiating fins 8 are inserted and hooked. In addition, this engagement hole 3a corresponds to the width of the leg portion 8a of the radiating fin 8, a rectangular vertical hole opened in the end face of the contact piece 3A, 3B, and the side surface of the contact piece so as to intersect with the vertical hole. It consists of a horizontal hole perforated.

  And in order to attach this radiation fin 8 to contact piece 3A, 3B, the end of contact piece 3A, 3B is made in the state bent so that the leg part 8a of the U-shaped radiation fin 8 might be approached inside. It is inserted into the vertical hole part of the engagement hole 3a opened in the part. As a result, the heat dissipating fin 8 is restored to its original shape by spring elasticity, and the leg portion 8a overlaps the inner wall surface of the engagement hole 3a in a heat transfer manner, and the engagement claw 8b at the tip engages with the side hole portion. Hold in position. The heat dissipating fin 8 can be mounted or replaced without restriction even after the contact pieces 3A and 3B of the fixed contact 3 are assembled to the terminal plates 2A and 2B (see FIG. 3).

  According to the above-described mounting structure of the heat dissipating fins 8, screwing operation is not required unlike the conventional structure, and the number of assembling steps can be simplified and the manufacturing cost can be reduced.

DESCRIPTION OF SYMBOLS 3 Fixed contact 3a Engagement hole 3A, 3B Contact piece 8 Radiation fin 8a Leg 8b Engagement claw

Claims (2)

A pair of terminal plates arranged at both ends of the mounting base and connected to the main circuit, a fixed contact composed of a plurality of contact pieces coupled to the terminal plate and arranged on the left and right sides, and opposed to the fixed contact It consists of a rotary bridge-shaped movable contact, and in the disconnector provided with a heat radiation fin for each contact piece as a heat radiation promoting means in the stationary contact,
A disconnector characterized in that the heat dissipating fins are attached by snap coupling to a fixed contact piece. The disconnector according to claim 1, wherein the heat dissipating fin has a structure in which a metal plate is bent in a U shape and an engagement claw is formed at a tip end of the leg, and the engagement claw is connected to the contact piece. A disconnector characterized by being fitted into an engagement hole formed at an end and snap-coupled.

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