JPS63209450A - Explosion-proof motor provided with removable brush holder - Google Patents

Abstract

PURPOSE:To enable carbon brushes to be always retained with constant pressure, by permitting the carbon brushes to come in pressure contact with a commutator, with spiral springs. CONSTITUTION:Current is conducted to a commutator 13 via a lead wire 47, lead wires 45, and carbon brushes 44, and the commutator 13, a rotor, and a motor shaft are integrally rotated. The carbon brushes 44 are pressed against the surface of the commutator 13 by the always constant pressure of spiral springs 43. Brush holders 36 are arranged in a cylindrical frame 10 via the openings 30 of opening sections 31 and brush holder inserting openings 34, 35, and are fixed on brush holder fitting bases 32.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to an explosion-proof motor equipped with a removable brush holder.

(b) Conventional technology and its problems A conventional explosion-proof motor is a wire-wound commutator motor, the structure of which is shown in FIG.

As shown in the figure, bearing brackets b are attached to both ends of the cylindrical frame a,
A sealed frame is formed by connecting the motors c in a hermetically sealed state, and within the same sealing frame, a motor shaft ``on which a commutator d and a rotor e are integrally attached is arranged concentrically. , both ends of the motor shaft f are rotatably supported by bearing brackets b and c.

Furthermore, a stator g for generating a magnetic field is fixed to a portion of the inner peripheral surface of the cylindrical frame a that is aligned with the rotor C.

Furthermore, the explosion-proof motor has a brush holding structure at a location corresponding to the commutator, and the brush holding structure includes a carbon brush h that makes sliding contact with the commutator d, and A completed carbon brush consisting of a compression coil spring i that presses the commutator d against the commutator d and a spring stopper j is attached to a brush holder k which is an insulator, and the brush holder k is attached to a cylindrical frame a.
It is constructed by detachably attaching it to the

(c) Problems to be Solved by the Invention However, such explosion-proof motors still have the following problems.

■Since the carbon brush is pressed against the commutator by a compression coil spring, the pressing force changes at the same time as the carbon brush wears.Changes in the brush pressing force, that is, variations, lead to variations in the carbon brush loss. It is difficult to obtain suitable motor characteristics over a long period of time.

(2) Since the brush holder is attached to the cylindrical frame a in a completely sealed state, it is difficult to inspect rectifying sparks and it is difficult to determine when it is time to replace the carbon brush h, which poses maintenance problems.

SUMMARY OF THE INVENTION An object of the present invention is to provide an explosion-proof motor equipped with a removable brush holder that can solve the above problems.

(d) Means for Solving the Problems The present invention provides a motor shaft having a commutator and a rotor rotatably disposed within a sealed frame, and a stator concentrically arranged around the rotor. In an explosion-proof motor in which a carbon brush is placed in sliding contact with a commutator in a sealed frame, an opening for inserting a brush holder is provided in the part of the sealed frame corresponding to the commutator, and the carbon brush is inserted through the opening. A brush holder having a brush holder is inserted into the sealed frame, and the opening area of the brush holder insertion opening is made sufficiently larger than the shape of the brush holder, and the brush holder is provided with a spiral spring that presses the carbon brush into contact with the commutator. This invention relates to an explosion-proof motor equipped with a removable brush holder.

(E) Actions and Effects With the above-described configuration, the present invention provides the following actions and effects.

■Since the carbon brush is brought into pressure contact with the commutator by a spiral spring, a constant pressing force can be maintained at all times regardless of whether the carbon brush is worn out, and the motor characteristics can be maintained constant over a long period of time. , the brush holder can be made into a small WI element and can be manufactured at low cost.

■Since the sealing frame has an opening for inserting a brush holder that has a sufficiently larger opening area than the brush holder, it is possible to install and remove the brush holder easily and quickly. The rectified spark can be checked and the carbon holder can be replaced at an appropriate time, making maintenance easier and improving safety.

(f) Examples The present invention will be specifically described below based on examples shown in the attached drawings.

First, the overall structure of the explosion-proof motor A will be explained with reference to FIG.
0 forms a sealed frame B by attaching bearing brackets 11 and 12 in close contact with each other at both ends thereof.

Further, within the sealed frame B, a motor shaft 15 having a commutator 13 and a rotor 14 integrally attached thereto is arranged concentrically, and both ends of the motor shaft 15 are provided with bearings 16.1, respectively.
It is rotatably supported on bearing brackets 11, 12 via 7.

Further, 18.19 is an explosion-proof ring provided adjacent to the bearing 16.17 in the bearing brackets 11 and 12,
This prevents rectifying sparks generated within the sealed frame B from leaking into the flammable gas outside.

Further, 20 is a stator made of permanent magnets arranged concentrically around the rotor 14, and the stator 20 is connected to the cylindrical frame 1.
The cylindrical yoke 21 is fixed to the inner circumferential surface of the cylindrical yoke 21 which is concentrically arranged inside the bearing bracket 1 .
1.12.

In addition, 24 is a tie rod extending in the axial direction gap formed between the stator 20 consisting of a pair of halves, and having both ends thereof engaged with the non-magnetic end plates 22 and 23, and having a cylindrical shape. This is used to strengthen the connection between the yoke 2I and the non-magnetic end plates 22 and 23.

Next, the structure of the brush holding structure C, which constitutes the gist of the present invention, will be specifically explained with reference to FIGS. 2 to 4.

As is clear from FIG. 3, the brush holding structures C are symmetrically provided on both sides of the cylindrical frame 10 at the same axial position as the commutator 13.

That is, an annular opening 31 is formed at the corner side of the cylindrical frame 10 to fit an opening 30 having a circular cross section. The annular opening 31 has crescent-shaped brush holder mounting seats 32.33 protruding from the front and back of its bottom, and between both mounting seats 32.33, a brush holder with a rectangular cross section is provided. An insertion opening 34 is formed.

Note that the brush holder insertion opening 34 has an opening area that is sufficiently larger than the shape of a brush holder 36, which will be described later.

Furthermore, at a position aligned with the brush holder insertion opening 34, the cylindrical yoke 21 is also formed with a brush holder insertion opening 35 having substantially the same shape and the same opening area as the brush holder insertion opening 34.

Reference numeral 36 denotes a brush holder disposed inside the cylindrical frame 10 through the brush holder insertion openings 34 and 35, and the brush holder 36 includes a fixing bolt 37 and a positioning bolt for fixing both bolts 1 to the brush holder mounting seats 32 and 33. 38, a brush holder mounting plate 39 made of an insulating material, an L-shaped fitting 41 whose base is fixed to the brush holder mounting plate 39 with a connecting bolt 40, and a brush holder attached to the tip of the L-shaped fitting 41. The commutator 13 is connected to the main body 42 and the main body 42 by a spiral spring 43 that is attached to the brush boulder body 42 and built in the brush holder body 42.
The carbon brush 44 is pressed into contact with the carbon brush 44.

Further, 45 is a lead wire whose one end is connected to the carbon brush 44 and the other end is connected to the relay fitting 46;
Reference numeral 47 denotes a lead wire that connects the relay fitting 46 to an external power source, and the lead wire 47 is surrounded by a protective gate 48.

In addition, in FIG. 2, 49 is a protective cover detachably attached to the opening 31.

Next, a method of using the explosion-proof motor A having the above configuration will be explained.

In normal operation, the outlet wire 47 and the lead wire 45,
By flowing current from an external power source to the commutator 13 via the carbon brush 44, the commutator 131, rotor 14, and motor shaft 15 can be rotated integrally.

In this operation, since the brush holder insertion openings 34 and 35 have a sufficiently larger opening area than the shape of the brush holder 36, when the protective cover 49 is removed from the opening 31, the brush holder insertion openings 34 and 35 are Through the openings 34, 35, the generation of sparks due to the sliding contact of the carbon brushes 44 with the commutator 13 can be easily checked.

Further, during operation, the carbon brush 44 is subject to wear and tear, but the spiral spring 43 can always press the carbon brush 44 against the surface of the commutator 13 with a constant pressing force.

Furthermore, when installing the brush holder 36, it is necessary to open the
Opening 30 of part 31 and brush holder insertion opening 34°35
The brush holder 36 is disposed inside the cylindrical frame 10 via the above, and then the brush holder mounting plate 39 is fixed to the brush holder mounting seats 32 and 33 with the fixing bolts 37 and the positioning pins 38.
6 can be easily fixedly attached to the cylindrical frame lO.

Similarly, the removal operation of the brush holder 36 can be easily and quickly performed by performing the above procedure in reverse.

In the above embodiments, the stator 20 is formed of a permanent magnet, but the stator 20 is not limited to this, and may be formed of an electromagnet as shown in FIG.

[Brief explanation of the drawing]

FIG. 1 is a partially sectional side view of an explosion-proof motor equipped with a removable brush holder according to the present invention, and FIG.
The sectional view taken along line -1, Figures 3 and 4 are, respectively,
FIG. 2 is a sectional view taken along the lines ■--■ and ■--■, and FIG. 5 is a partially sectional side view of a conventional explosion-proof motor. In the figure, A: Explosion-proof morph B: Sealing frame 13: Commutator 14: Rotor 15: Morph shaft 20: Stator 34: Brush holder insertion opening 36: Brush holder 43: Clockwork spring 44: Carbon brush

Claims (1)

[Claims] 1. A commutator (13) and a rotor (14) are provided in the sealed frame (B).
) is rotatably arranged, a stator (20) is arranged concentrically around the rotor (14), and within the sealed frame (B), In an explosion-proof motor in which a carbon brush (44) is brought into sliding contact with a commutator (13), an opening (34) for inserting a brush holder is provided in a portion of the sealed frame (B) corresponding to the commutator (13); Same opening (34)
A brush holder (36) equipped with a carbon brush (44) is inserted through the sealing frame (B), and the opening area of the brush holder insertion opening (34) is sufficiently larger than the shape of the brush holder (36). Furthermore, the carbon brush (44) is attached to the commutator (13) in the brush holder (36).
An explosion-proof motor equipped with a removable brush holder, characterized in that it is equipped with a clockwork spring (43) that presses into contact with the brush holder.