JPS59216456A - Dc coreless motor - Google Patents

Abstract

PURPOSE:To enhance the performance of a DC coreless motor and to reduce the size of the motor by oppositely disposing a magnet to hold a rotor coil, and disposing the wiring unit of the coil to a commutator on the surface of the coil opposite to the commutator. CONSTITUTION:A DC coreless motor has a top bracket 21 including a yoke 11a and a bearing unit 20a, a sleeve 14 which performs the function of a cylinder of a housing, and end bracket 22 including a yoke 11b, a brush 13 and a bearing unit 20b, a rotor 23 including a commutator 16, a rotor coil 17, a substrate 18 and a ring varistor 19 with a rotor shaft 15 as a center, and magnets 12a, 12b disposed at both the bracket 21 and the bracket 22. In the rotor 23, the commutator 16 id disposed at the end bracket 22 side to the rotor coil 17, and the substrate 18 for wiring between the commutator 16 and the coil 17 is disposed at the bracket 21 side. A housing is separated into the bracket 21 and the sleeve 14 of two elements.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention particularly relates to a DC coreless motor with a diameter of 258 or less and a thickness of IOM or less, and aims to easily realize a high-performance DC coreless motor with a small diameter and thin thickness. .

Conventional DC coreless motors generally have the structure shown in Fig. 1, which consists of a housing 1, a rotor shaft 2, a rotor coil 3, a ring varistor, or a wiring board 4 and a commutator 5. consisting of a rotor 9, a yoke 6 and a brush 8
It is composed of an end bracket IDa consisting of and a magnet 7.

With the recent miniaturization of equipment, there is a demand for high-performance motors with a small diameter and thin thickness. In order to improve the characteristics in a limited space, it is necessary to maximize the magnetic flux density in the gap in which the rotor coil 3 is arranged. However, in a magnetic circuit in which the magnet 7 is arranged only in the end bracket 10a as shown in FIG. 1, magnetic flux leakage occurs and it is difficult to obtain a sufficient magnetic flux density in the gap. Therefore, in the conventional example shown in FIG. 2, the magnet Z is divided and a part thereof is placed in the housing 1 to form a magnet-opposed magnetic circuit to suppress the occurrence of the magnetic flux leakage component as much as possible. The housing 1. End bracket I
Magnets 7a and 7b are arranged at Ql), respectively. With this structure, even if the characteristics are completely satisfied, the volume of the ring varistor as a connection part between the rotor coil 3 and commutator 5 in the rotor 9, or the volume of the connection board 4 and the volume of the commutator 50 can be accommodated. Therefore, a problem arises in that the thickness on the end bracket 10b side increases. Furthermore, it is difficult to magnetize the grinding stone 7a after it is assembled into the housing 1, and the thickness of the cylindrical portion of the housing 1 is unnecessarily thick because it is processed integrally with the bottom surface of the yoke.
Since the diameter of the motor becomes large, it is difficult to provide a motor with a small diameter and thin thickness while satisfying high characteristics fC.

The present invention has been made to eliminate all of the above problems and to easily provide a motor with high performance and a small external size.

As a method for achieving this, in order to obtain the characteristics, a magnetic circuit is adopted in which magnets are placed facing each other so as to sandwich the rotor coil, and at the same time, the connection between the rotor coil and the commutator is placed on the side opposite to the commutator with respect to the rotor coil. By making the thickness as thin as possible and separating the nozzle into two parts, the bottom part and the outer circumferential part, the diameter is made as small as possible, and all of the above problems have been solved.

Embodiments of the present invention will be described below with reference to the drawings.

As shown in FIG. 5, the DC coreless motor according to the present invention includes a top bracket 21 consisting of a yoke 11a and a bearing portion 20a, a sleeve 14 that functions as the cylindrical portion of a conventional nose ring. Yoke 11b, blank 15, and bearing portion 20b
An end racket consisting of 22. The rotor 25 consists of a commutator 16, a rotor coil 17, a substrate 1, and a ring 19 centered around the rotor shaft 15, and magnets 12a and 12b arranged on both the racket 21 and the end bracket 22. Basically configured. In the rotor 25, the commutator 16 is arranged on the end bracket 22 side with respect to the rotor coil 17, and the base plate 18 for connecting the commutator 16 and the rotor coil 17 is arranged on the top bracket 21 side. . By adopting this structure, the top bracket 21 and the end bracket 22
It becomes possible to effectively utilize the space created by the inner diameter and thickness of the magnets 11a and 11b arranged in the magnets 11a and 11b.

Furthermore, by separating the conventional housing into the top bracket 21 and sleeve 1402, the conventional Q11
It enables rational design that is not affected by limitations in engineering capacity.

Incidentally, FIG. 4 shows an embodiment in which a self-aligning bearing 20c is employed in the toe racket 21.

According to the present invention, (1) both the magnets disposed on the top bracket side and the end bracket side can be easily magnetized after assembly, thereby increasing productivity and forming an opposed magnet type magnetic circuit.

(2) For the yoke, which requires a considerable thickness to avoid magnetic saturation, the sleeve part, which is a separate component, can be thick enough to satisfy mechanical strength, and the diameter is smaller than that of conventional housings. be advantageous to

(3) High characteristics can be obtained with a configuration with opposed magnets without increasing the thickness when configured with a single-sided magnet.

It has remarkable effects such as

[Brief explanation of drawings]

1 and 2 are sectional views of a conventional DC coreless motor, and FIGS. 3 and 4 are sectional views of a DC coreless motor according to the present invention. 1...Housing 3.17...Rotor coil 5.16...Commutator 6.11...Yoke 7.12...Magnetic Stone 923...Rotor 10.22...End bracket 14...
...Sleeve 21...Top bracket and above Applicant Daini Seikodai Co., Ltd. Figure 1 Figure 2 Figure 3 (21 Figure 4)

Claims (2)

[Claims] (1) In a DC cobbles motor, which consists of a rotor consisting of a commutator, a rotor coil, and a connection between the two, a housing, an end bracket, and a magnet, the magnet is arranged in both the housing and the end bracket, and the rotor coil is connected to the rotor in the rotor. On the other hand, a DC coreless motor is characterized in that a commutator is arranged on the end bracket side, and a connection part between the rotor coil terminal and the commutator is further arranged on the nozzle side with respect to the rotor coil. (2) The DC coreless morph according to claim 1, characterized in that the housing is composed of a yoke, a bracket, and a sleeve.