JPH11136900A - Terminal box structure for electric apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To attain large reduction in number of parts, saving of terminal block material, and workability improvement in a terminal box with terminal block of an electric apparatus. SOLUTION: A box part 2 of a terminal block 4 and a terminal box 1 are integrally molded out of resin. At the back side of the terminal block 4, a nut mounting part 10 involving a locking part 11 of a hexagonal nut 5 and a breaking-off preventing claw part 12 are fitted by molding. The hexagonal nut 5 is pushed in the nut mounting part 10 for fitting, and a lead wire 8 and an external cable 9 for electric apparatus are tightened together, using the hexagonal nut 5 and the bolt 7.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a three-phase induction motor, etc.
The present invention relates to a structure of a terminal box with a terminal block of an electric device.

[0002]

2. Description of the Related Art A conventional terminal box structure of an electric device will be described with reference to examples shown in FIGS. 7 and 8 and examples shown in FIGS.

The terminal box structure shown in FIGS. 7 and 8 has a box portion 202 separate from the motor body 100 and a cover portion 203 thereof.
And a terminal block 204 separate from them is mounted in a terminal box 201 composed of 205 is a terminal block fixing bolt, 206 is an electric motor lead wire, 207 is an external cable from an external power supply, 208 is a bolt for connecting the lead wire and the terminal block (short circuit board), 209 is a cable insertion hole, and 210 is a cable insertion hole. Bushing, 211 is a box fixing bolt,
212 indicates a grounding bolt.

As the terminal box 201, a metal (press, cast, aluminum die-cast, etc.) is most often used. This is because the operating environment of the electric motor is very wide, and the terminal box 201, which is one of the components of the electric motor, is required to have mechanical strength, heat resistance, weather resistance, and the like. In the case of the metal terminal box 201, the terminal block 204 separate from the terminal box 201 is screwed with a bolt 205 because the conductive portion needs to be insulated.

More specifically, the box 202 and the terminal block 204 are fastened together by bolts 205 and fixed to the motor body 100.

The structure of the terminal block 204 includes a bush type, a terminal block type, a stud bolt type, and the like.
Can support these plural types of terminal block structures.

On the other hand, in the terminal box structure illustrated in FIGS. 9 and 10, a box portion 302 is integrated with the motor body 100, and a terminal box 301 composed of the box portion 302 and its cover portion 303 has This is a structure to which a terminal block 304 is attached.
This terminal box 301 is also made of metal, and a separate terminal block 304 is screwed with bolts 305 to insulate the conductive parts. The terminal block 304 has a bushing type, a terminal block type, a stud bolt type, and the like.
Can support these plural types of terminal block structures.

Some small motors have a terminal box made of resin, but the terminal block and the terminal box are separated from each other due to restrictions on the terminal structure.

[0009]

The prior art described above includes terminal boxes 201 and 301 (particularly, box sections 202 and 3).
02) and the terminal blocks 204 and 304 are separate components, and therefore have the following problems. Note that these problems are not limited to the electric motor, but also occur in the terminal box structures of various electric devices. (1) The number of parts is large because bolts 205 and 305 for connecting the terminal boxes 201 and 301 and the terminal blocks 204 and 304 are required. (2) Since the terminal blocks 204 and 304 are individual components, it is necessary to partially increase the thickness of the terminal blocks 204 and 304 to secure the strength, which requires more material. (3) When the terminal box 201 is separate from the motor body 100 as shown in FIGS. 7 and 8, the terminal box 201 and the terminal block 204
And the tightening work was troublesome.

[0010]

According to a first aspect of the present invention, there is provided a terminal box structure for electric equipment having a terminal block inside a terminal box including a box and a cover. The box portion and the terminal block are formed into an integral structure using a resin material.

According to a second aspect of the present invention, the terminal block is provided with a bolt insertion hole and a nut mounting portion for fastening a lead wire of an electric device and an external cable together with a bolt and a hexagonal nut. The nut mounting portion is provided with a detent portion for preventing rotation of the hexagon nut and a claw portion for preventing the hexagon nut from falling off by molding.

According to a third aspect of the present invention, the terminal block is provided with a bolt insertion hole and a nut mounting portion for fastening a lead wire of an electric device and an external cable together with a bolt and a hexagonal nut. A hexagonal nut is mounted on the nut mounting portion by integral molding.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. FIG. 1 is a cross-sectional view showing a terminal box structure of an electric device according to an embodiment of the present invention, FIG. 2 is a cross-sectional view of a terminal block portion taken along line II in FIG. 1, and FIG.
FIG. 4 is a front view of the inside of the terminal box, FIG. 4 is a rear view of the terminal box, FIG. 5 is a view showing a mounted state of a hexagonal nut, and FIG. 6 is a sectional view of a nut mounting portion.

In the figure, 1 is a terminal box, 2 is a box portion of the terminal box, 3
Is a terminal box cover, 4 is a terminal block, 5 is a nut, 6 is a bolt insertion hole, 7 is a bolt, 8 is a lead wire of an electric device, 9
Is an external cable, 10 is a nut mounting portion, 11 is a detent portion, 12 is a claw portion, 13 is a projection, 14 is a fitting for a lead wire, 14A is a hole in the fitting 14, 15 is a lead wire insertion hole, 16 is a lead wire insertion hole, Is a cable insertion hole, 17 is a connection fitting of an external cable, 17A is a hole of the connection fitting 17, 18 is a mounting hole of a terminal box, and 19 is a screw hole for mounting a cover.

As shown in FIG. 1, the terminal box 1 is formed of a resin (plastic) in a two-part shape including a box part 2 and a cover 3 thereof. Further, the terminal block 4 and the box portion 2 are integrally formed by resin.

Specifically, the box portion 2 is formed so that the bottom of the box portion 2 has a partially raised shape, and the raised portion is used as the terminal block 4.

As a result of partially lifting the bottom of the box 2, a space is created behind the terminal block 4. Therefore, it is possible to arrange nuts 5 for the number of phases in this back space, and the terminal block 4
The bolts 7 are passed through the bolt insertion holes 6 corresponding to the number of phases, and the lead wires 8 of the electric apparatus and the external cables 9 are connected together by the bolts 7 and the nuts 5. The bolt insertion hole 6 is formed in the terminal block 4 by molding.

In this embodiment, a hexagonal nut is used as the nut 5, and as shown in FIGS. 1 and 4 to 6, a cylindrical nut is formed integrally with the terminal block 4 on the back side of the terminal block 4 by molding. A mounting unit 10 is provided.

As shown in detail in FIG.
The inner periphery of 0 is formed in a hexagonal shape by molding. 6
The size of the square is such that the hexagonal nut 5 can be attached and the hexagonal nut 5 is prevented from rotating. Therefore,
The inner peripheral portion of the nut mounting portion 10 functions as a rotation preventing portion 11 so that the hexagon nut 5 does not run idle when the screw is tightened.

As shown in detail in FIG. 6, the inner periphery of the nut mounting portion 10 is provided with two claw portions 12 projecting inward by molding. When the hex nut 5 is pushed in, the claw portion 12 is dented by elastic deformation so that the hex nut 5 can be inserted, and after insertion, the claw portion 12 is restored to a shape and size capable of preventing the hex nut 5 from falling off. Has become. Therefore,
When the bolt 7 is pushed into the hexagonal nut 5, the hexagonal nut 5 is not caught by the claw portion 12 and does not fall off.

As shown in FIGS. 2 and 3, the terminal block 4 is provided with an appropriate number of projections 13 by molding. Projection 1
Reference numeral 3 denotes an L or T shape, and is located near the bolt insertion hole 6. The gap between the protrusion 13 and the terminal block 4 is substantially the same as or slightly smaller than the thickness of the connection fitting 14 at the end of the lead wire 8.

Therefore, the connection fitting 14 is connected to the two projections 13.
In this state, the hole 14A of the connection fitting 14 is aligned with the bolt insertion hole 6 and can be held by the elastic force of the projection 13.

As shown in FIG. 1, a lead wire insertion hole 15 for passing the lead wire 8 is provided by molding in the middle of the slope from the bottom of the box portion 2 to the terminal block 4 portion. Further, a cable insertion hole 16 for passing the external cable 9 is provided on the side surface of the box portion 2 by molding.

As shown in FIGS. 3 and 4, a mounting hole 18 for mounting the terminal box 1 to an electric equipment main body (not shown) is formed at the bottom of the box portion 2 by molding or by embedding a nut. It is.

The box 2 is provided with a screw hole 19 for mounting the cover 3 by molding or by embedding a nut.

Although not shown, a hole corresponding to the screw hole 19 of the box 2 is formed in the cover 3 by molding.

Further, the joint between the box 2 and the cover 3
The cover portion 3 is formed into a shape of a stainless steel joint so that the cover portion 3 is fitted into the box portion 2 from the outside.

The resin material for forming the box portion 2 of the terminal box 1 and the terminal block 4 into an integrally molded product and the resin material for forming the cover portion 3 of the terminal box 1 as a molded product include weather resistance, A material excellent in heat resistance, mechanical strength and insulation performance is used, thereby satisfying the characteristics required for both the terminal box 1 and the terminal block 4.

The above-mentioned terminal box 1 has a rated current of 20 A, for example.
It is useful for use as a terminal box with a terminal block for a small three-phase induction motor up to a small size.

Here, the terminal box 1 is attached to the three-phase induction motor, and the lead wires 8 and the external cables 9 on the terminal block 4 are connected.
An example of the work procedure on the manufacturer side and the customer side regarding the combination of the above is shown below.

<Work on the Manufacturer Side> (1) As shown in FIGS. 4 to 6, the manufacturer pushes the hexagonal nuts 5 into the nut mounting portions 10 on the back side of the box portion 2 and mounts them. (2) Next, as shown in FIG. 1, the lead wire 8 of the electric motor is introduced into the box portion 2 through the lead wire insertion hole 15. On this occasion,
A bushing is attached to the lead wire insertion hole 15 as necessary. (3) In this state, a bolt (not shown) is passed through the mounting hole 18 of the box 2 and screwed into a screw hole (not shown) of the motor body, and the box 2 is attached to the motor body. (4) Next, as shown in FIGS. 1 to 3, the connection fitting 14 at the tip of the lead wire 8 is inserted under the corresponding projection 13 of the terminal block 4, and the hole 14 </ b> A is aligned with the bolt insertion hole 6. I do. (5) In this state, pass the bolt 7 through the bolt insertion hole 6,
The lead wire 8 is fixed to the terminal block 4 by screwing it into the hex nut 5. (6) Next, cover part 3 is put on box part 2, and bolts (not shown) are screwed into screw holes 19 to fix cover part 3 to box part 2.

<Work on Customer Side> (1) The customer removes the cover 3 from the box 2 and the bolt 7 from the hexagonal nut 5. (2) Next, as shown in FIG. 1, an external cable 9 from an external power supply is introduced into the box portion 2 through the cable insertion hole 16,
The connection fitting 17 at the tip is overlapped with the corresponding connection fitting 14 on the terminal block 4, and the hole 17 </ b> A of the connection fitting 17 is connected to the connection fitting 14.
To the hole 14A. At this time, a bushing is attached to the cable insertion hole 16 as necessary. (3) In this state, pass the bolt 7 through the bolt insertion hole 6,
Screw the lead wire 8 and the external cable 9
To join. (4) Finally, cover part 3 is put on box part 2, and a bolt (not shown) is screwed into screw hole 19 to cover part 3 in box part 2.
Fixed to.

In the above example, the nut mounting portion 10 is formed in advance, and the hexagonal nut 5 is pushed in and mounted later, but when the box portion 2 and the terminal block 4 are integrally formed, the hexagonal nut 5 is formed.
May be integrally molded with the nut mounting portion 10.

If the hexagon nut 5 is integrally molded as described above, the operation of pushing the hexagon nut 5 into the nut mounting portion 10 and mounting it in the above-described operation procedure example can be omitted.

In the above example, the cover 3 is formed of resin, but it may be made of metal.

Further, in the above-described example, the use of a three-phase induction motor as a terminal box has been described. However, the present invention is not limited to a three-phase induction motor, but may be any other type of general electric equipment such as various motors and generators. It is possible to apply to.

[0037]

According to the first aspect of the present invention, the following effects can be obtained. (1) Since a bolt for connecting the terminal box and the terminal block is unnecessary, the number of parts can be significantly reduced. (2) Since the box portion and the terminal block are integrally formed, the mechanical strength can be increased, and the portion of the conventional terminal block that has been thickened to secure the strength can be thinned. Therefore, material can be saved. (3) Tightening work is simplified and workability is improved as compared with the conventional structure in which the terminal box and the terminal block are fastened together. This makes it easier to perform automation and the like. (4) From the above points, it is effective for cost reduction.

According to the second aspect of the present invention, the lead wire of the electric device and the external cable can be easily fastened together with the bolt and the hexagonal nut simply by mounting the hexagonal nut on the nut mounting portion.

According to the third aspect of the present invention, since the hexagonal nut is mounted on the nut mounting portion by integral molding, the lead wire and the external cable can be more easily fastened together.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a terminal box structure of an electric device according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along line II of FIG. 1 showing a sectional structure of a terminal block portion.

FIG. 3 is a front view of the inside of the terminal box.

FIG. 4 is a rear view of the terminal box.

FIG. 5 is a view showing a mounting state of a hexagon nut.

FIG. 6 is a sectional view of a nut mounting portion.

FIG. 7 is a front view of the electric motor according to the related art, excluding a cover of a terminal box structure.

FIG. 8 is a sectional view of the terminal box of FIG. 7;

FIG. 9 is a side view of a terminal box structure of another electric motor according to the related art.

FIG. 10 is a front view showing the inside of the terminal box shown in FIG. 9;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Terminal box 2 Box part 3 Cover part 4 Terminal block 5 Hexagon nut 6 Bolt insertion hole 7 Bolt 8 Lead wire of electric equipment 9 External cable 10 Nut mounting part 11 Detent part 12 Claw part 13 Projection part 14 Lead wire connection Fittings 14A, 17A Connection fitting holes 15 Lead wire insertion holes 16 Cable insertion holes 17 External cable connection fittings 18 Terminal box mounting holes 19 Cover mounting screw holes

Claims (3)

[Claims] 1. A terminal box structure of an electric device having a terminal block inside a terminal box composed of a box portion and a cover portion,
A terminal box structure for electric equipment, wherein the box portion and the terminal block are formed into an integral structure using a resin material. 2. The terminal block is provided with a bolt insertion hole and a nut mounting portion for fastening a lead wire of an electric device and an external cable together with a bolt and a hexagonal nut, and the nut mounting portion further includes: 2. The terminal box structure for an electric device according to claim 1, wherein a detent part for preventing rotation of the hexagon nut and a claw part for preventing the hexagon nut from falling off are provided by molding. . 3. The terminal block is provided with a bolt insertion hole and a nut mounting portion for fastening a lead wire of an electric device and an external cable together with a bolt and a hexagonal nut, and the nut mounting portion further includes a nut mounting portion. The terminal box structure for an electric device according to claim 1, wherein the hexagonal nut is mounted by integral molding.