JPH02273060A - Shaft insulation for commutator motor - Google Patents

Abstract

PURPOSE:To improve workability and insulating property in automatic assembling by a method wherein a shaft insulation is formed by molding a shaft integrally with a core and a tubular section at the outside of the core of the shaft insulation is formed so as to be tapered. CONSTITUTION:The shaft 1 of a motor is molded by resin integrally with the core 2 of a rotor. An insulator 5 is inserted between the core 2 and a coil 3. A shaft insulation 11 is constituted of the shaft 1, the core 2 and the resin of the coil 3 while the tubular section thereof is molded by resin on the outer periphery of the shaft 1 along the end surface side of the core 2 so as to have a large diametral tapered shape. The shaft insulation is molded by resin integrally so as to position the resin between the shaft and the core in such a manner whereby the insulating performance of the shaft and the core may be improved. On the other hand, the tubular section is molded so as to have the tapered shape whereby workability upon inserting an insulator may be improved. Further, a gap in the abutting surface of the shaft insulation against the insulator is eliminated whereby insulating performance may be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to commutator motors used in electric blowers for vacuum cleaners, juice mixers, etc., and particularly to insulation of their shafts.

2. Description of the Related Art In recent years, commutator motors have been improved in performance and quality, and in particular, commutator motors with high insulation performance are in demand. Conventional rotor shaft insulation for commutator motors uses paper treated with varnish.

An example of the conventional rotor shaft insulation described above will be described below with reference to the drawings.

5, 6, 7, and 8 show conventional rotor shaft insulation. In FIG. 6, 1 is the shaft of the electric motor. 2 is the rotor core (hereinafter abbreviated as core), and shaft 1
is press-fitted into the A coil 3 is wound within the slot of the iron core 2. 4 is a commutator to which the winding ends of the coil 30 are connected.

5 is an insulator for insulating the iron core and the coil 3, and is mounted on the shaft before the coil 3 is wound.

6 is shaft insulation between the shaft 1 and the coil 3, and is mounted after the insulator 5 is mounted and before the coil 3 is wound. In FIG. 5, 7 is a slot insulation for insulating the slot portion of the iron core 2 and the coil 3.

First, the iron core 2 is press-fitted into the shaft 1, the insulator 5 is attached, the shaft insulation 6 is attached, the slot insulation 7 is inserted into the slot part of the iron core 2, and the commutator 4 is press-fitted into the shaft 1. Winding is performed on the iron core 2, and the winding end of the coil 3 is connected to the commutator 4.
It is connected to.

Problems to be Solved by the Invention However, in the above configuration, the insulator 5
After installing the insulator 5 along the shaft 1, the shaft insulator 6 is installed along the shaft 1. At this time, if the end face of the shaft insulation 6 is deformed or there is a crack, the insulator 5 and the shaft insulation 6 A gap is formed at the contact surface between the shaft 1 and the coil 3, and the insulation between the shaft 1 and the coil 3 deteriorates. Attach the shaft insulation 6 first, then insulator 5.
There is also a method of attaching the insulator 5, but in the case of automatic assembly, when attaching the insulator 5 to the outer diameter of the shaft insulator 6, it gets caught on the end face of the shaft insulator 6, making attachment difficult. Further, when inserting the slot insulator 7 into the slot portion of the iron core 2, there is a problem in that the insulator 5 is lifted off the end face of the iron core, and the insulator 5 has to be reinstalled.

In addition, since the surfaces of the insulator 5 and the shaft insulation 6 are smooth, there are many contact parts with the coil 3, which impairs heat dissipation from the coil 3 and increases the temperature rise.

In view of the above problems, the present invention provides a commutator motor that improves workability in automatic assembly, improves insulation performance, and reduces temperature rise in the windings.

Means for Solving the Problems In order to solve the above-mentioned problems, the shaft insulation of the present invention includes at least a shaft insulation formed by integrally molding a resin between an armature shaft and an iron core. One cylindrical portion is tapered toward the core side, and uneven grooves are provided on the outer diameter of this cylindrical portion along the axial thrust direction.

Effect of the Invention With the above-described configuration, the present invention can improve the insulation performance of the shaft and the iron core by integrally molding the resin so that the resin is positioned between the shaft and the iron core, and the cylindrical portion is molded into a tapered shape. By doing so, it is possible to improve the workability when inserting the insulator, and to improve the insulation at the contact portion between the shaft insulation and the insulator. Furthermore, the uneven portion formed on the outer diameter of the cylindrical portion of the shaft insulation allows the area in contact with the coil to be made as small as possible, thereby reducing the temperature rise of the winding.

EXAMPLE Below, shaft insulation according to a first example of the present invention will be explained with reference to the drawings.

FIG. 1 shows the state after winding in an embodiment of the present invention. In FIG. 1, 1 is the shaft of the electric motor. 2
is the iron core of the rotor and is molded integrally with the shaft 1 using resin. A coil 3 is wound within the slot of the iron core 2. A commutator 4 is connected to the end of the coil 3.

5 is an insulator between the iron core 2 and the coil 3. 11
is a shaft insulation made of resin between the shaft 1, the iron core 2, and the coil 3. FIG. 2 shows the shape of the cylindrical portion of the shaft insulator 11 in the first embodiment of the present invention, which is molded with resin on the outer periphery of the shaft 1 into a tapered shape with a larger diameter toward the end surface of the iron core 2. There is.

First, the shaft 1 and the iron core 2 are molded together with the shaft insulation 11 using resin, the insulator 5 is attached, the slot insulation 7 is inserted into the slot part of the iron core 2, and the commutator 4 is attached to the shaft 1.
After being press-fitted into the coil 3, winding is performed, and the winding end of the coil 3 is connected to the commutator 4.

When installing the insulator 5, since the shaft insulation 11 is tapered, it can be installed without getting caught on the shaft insulation 11.Also, since the shaft insulation 11 is tapered, the insulator 5 can be installed on the iron core side. Since the coil 3 and the iron core 2 are press-fitted, the insulation performance between the coil 3 and the iron core 2 can be improved.

As described above, according to this embodiment, by molding the shaft insulation into a tapered shape with resin, the insulator 5 can be easily installed by automatic assembly, and there is no gap between the outer diameter of the shaft insulation 11 and the inner diameter of the insulator 5. Therefore, insulation performance can be improved.

Next, a second embodiment of the present invention will be described with reference to the drawings. FIG. 3 shows a shaft insulating cylindrical portion in a second embodiment of the present invention. In FIG. 3, reference numeral 22 denotes a shaft insulator integrally molded with the shaft 1, and has the same structure as that in FIG. 1. The difference from the configuration shown in FIG. 1 is that a groove 23 consisting of unevenness is formed in the axial direction on the outer diameter side of the cylindrical portion of the shaft insulation 22.
This is because the contact area with the coil 3 is small.

As mentioned above, by integrally molding the shaft insulation with the convex part on the outer diameter side of the cylinder, only the convex part comes into contact with the coil, which greatly reduces the contact area and increases the temperature of the winding. In this embodiment, the uneven grooves 23 on the outer diameter side of the cylindrical portion have a continuous shape, but may have an intermittent shape.

Effects of the Invention As described above, the present invention insulates the shaft and the iron core by integrally molding at least the space between the shaft and the iron core with resin, thereby insulating the shaft and the iron core. By forming the insulator into a tapered shape that becomes thicker toward the core side, it is possible to improve the workability of inserting the insulator during automatic assembly, and to improve the insulation performance by eliminating the gap between the contact surface with the insulator. I can do it.

In addition, uneven grooves are provided on the outer diameter side of the cylindrical portion of the shaft insulation to reduce the contact area with the coil (this makes it possible to lower the temperature rise of the motor and provide a more reliable motor). Yes, if we keep the temperature rise the same,
A motor with higher output or lower cost can be provided.

[Brief explanation of drawings]

FIG. 1 is a half-sectional view showing the state of the rotor after winding in the first embodiment of the present invention, and FIG. 2 is a perspective view of the cylindrical portion of shaft insulation in the first embodiment of the present invention. 3 is a perspective view of the cylindrical portion of the shaft insulation in the second embodiment of the present invention, FIG. 4 is a plan view seen from the direction A in FIG. 3, FIG. 5 is a perspective view of the slot insulation, and FIG. The figure is a half-sectional view showing the state of the rotor after winding in a conventional embodiment, FIG. 7 is a perspective view of an insulator in a conventional embodiment, and FIG. 8 is a perspective view of shaft insulation in a conventional embodiment. It is. 1...shaft, 2...iron core, 3...
・Coil, 5... End insulator, 11
...Shaft insulation, 23...Irregular grooves on the outer diameter side of the cylinder. Name of agent: Patent attorney Shigetaka Awano and one other person (Fig. Figure Figure Figure Figure

Claims (2)

[Claims] (1) Shaft insulation formed by integrally molding at least the space between the rotor core and the shaft with resin in order to insulate the rotor core of the motor and the armature winding wound around the rotor core from the shaft. , A shaft insulation for a commutator motor in which a cylindrical portion of the shaft insulation outside the rotor core is tapered to become thicker toward the core side. (2) The shaft insulation for a commutator motor according to claim 1, wherein uneven grooves are provided along the shaft thrust direction on the outer diameter of the cylindrical portion outside the rotor core of the shaft insulation.