JPH0191644A - Brushless motor - Google Patents

Abstract

PURPOSE:To promote the miniaturization of a bearing device by constituting a motor forming thermo-setting resin on the sensing surface of a position sensor as thin as possible so as to obtain a space distance from a sensor-use permanent magnet, arranged in the end face of a rotor core, to a minimum limit. CONSTITUTION:This electric motor solidifies its printed board 4 to be integrally molded by thermo-setting resin with a stator core 1 and a winding 3, forming a stator 7. Of the internal contour part of the stator 7, a magnetic sensing surface part of Hall elements 6 very thinly forms the thermo-setting resin, and a sensor magnet 10, fixed to the end face part of a rotor core 9, is formed being opposed to a sensor magnet corresponding part 8. While in the internal contour part of the stator 7, a housing part 11 for a bearing device is formed, inserting the bearing device 12a to be fixed and mounting another bearing device 12b to be adapted to an end surface part of the stator 7 and fixed by a rivet 13.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a brushless motor used as a drive source for a blower fan of a domestic air conditioner or the like.

Conventional technology In recent years, DC brushless motors have been adopted as the blower drive source for indoor heat exchangers in air conditioning equipment such as home air conditioners, but on the other hand, an inexpensive method of SCR control of single-phase induction motors has also been adopted. There is a growing demand for high efficiency, good controllability, and cost reduction for DC brushless motors.

A conventional brushless electric motor had a structure as disclosed in Japanese Patent Application No. 60-90053.

Hereinafter, a conventional brushless electric motor will be explained based on the drawings.

FIG. 5 is a longitudinal sectional view of the brushless electric motor disclosed in Japanese Patent Application No. 60-90053.

A winding 3 is applied to an insulating layer 2 applied to the stator core 1, and a sensor 6 on a printed circuit board 4 is attached to a predetermined position from the surface of the printed circuit board 4 by a sensor fixing base 17. The stator 7 is formed by molding together with the wires 3 and the like using a thermosetting resin, and the bearing device 12 is fixed with a rivet 13 through a through hole 18 provided in the stator so as to sandwich the stator 7 therebetween. On the other hand, the rotor is the shaft 19
The rotor core 9 and permanent magnets 14 are fixed to each other, and the sensor 6 detects the magnetic flux of the permanent magnet end 14a to form a brushless electric motor.

Problems to be Solved by the Invention With the above configuration, the sensor is attached to the printed circuit board via the sensor fixing base, which makes the mounting work difficult and requires an auxiliary part called the sensor fixing base. Further, since the bearing device is fixed through a through hole provided in the stator in order to rotatably fix the rotor, the bearing device becomes a large-sized bearing device.

Means for Solving Problems In order to solve the problems of the conventional example, the present invention provides winding through an insulating layer of an annular stator core having a plurality of slots, and a drive circuit is mounted on a printed circuit board. The drive circuit parts are placed between the windings, the position sensor is placed on the inner diameter side of the other drive circuit parts, and the side of the printed circuit board on which the drive circuit parts are mounted faces the end face of the stator core. At the same time, the stator core, windings, and printed circuit board are integrally molded and solidified with thermosetting resin to form an identifier. At this time, the thermosetting resin on the sensing surface of the position sensor is formed to be as thin as possible, and the spatial distance from the permanent magnet for the sensor placed on the end face of the rotor core is minimized. .

Further, a housing for a bearing device is formed on the inner diameter portion of the stator using a thermosetting resin, a small bearing device is inserted into this housing portion, and the other bearing device is attached by coming into contact with the end face portion of the stator. In order to fix the bearing devices disposed at these two locations concentrically, they are fixed by rivets or the like using through holes from the end face of the stator.

By adopting a configuration that is more than functional, a sensor fixing stand becomes unnecessary, and the sensor installation work becomes extremely easy.

Further, the bearing device is inserted and fixed in the bearing housing portion formed in the inner diameter portion of the stator, so that a small bearing device can be adopted. Furthermore, since the sensor magnet is attached to the end face of the rotor and the sensor is placed inside the stator, a small sensor magnet can be used.

Embodiments Hereinafter, embodiments of a brushless electric motor according to the present invention will be described in detail with reference to the drawings.

FIG. 1 is an assembly diagram of a stator winding of a brushless motor according to an embodiment of the present invention. In FIG. 1, an insulating layer 2 is applied to a stator core 1, and a winding 3 is wound thereon. On the other hand, the printed circuit board 4 has a protrusion 4a for winding the winding, a protrusion 4b for attaching the lead wire, and notches 4c and 4d on its outer periphery, and is formed into an almost oblong shape with a round hole. Power IC5a
and other drive circuit parts 5b are arranged between the windings 3, and a Hall element 6, which is a position sensor, is arranged at the innermost side of the printed circuit board 4.

FIG. 2 is a vertical half-sectional view of the brushless electric motor of the present invention. On the printed circuit board 4, a stator 7 is formed of thermosetting resin together with the stator core 1 and the winding 3.

An extremely thin layer of thermosetting resin is formed on the magnetic sensing surface of the Hall element 6 in the inner diameter of the stator 7, forming a sensor magnet corresponding portion 8, which is fixed to the end surface of the rotor core 9. A sensor magnet 10 is configured to face the sensor magnet corresponding portion 8.

Furthermore, a bearing device housing portion 11 is formed in the inner diameter portion of the stator 7, into which a bearing device 12a is inserted and fixed, and the other bearing device 12b is in contact with the end face portion of the stator 7. It is attached with a rivet 13 and fixed with a rivet 13. At this time, the head 13a of the rivet is attached to the stator 7 in direct contact with the end face portion thereof.

On the other hand, the driving magnet 14 is fixed to the outer diameter of the rotor core 9.

Furthermore, a cylindrical part 15 concentric with the bearing device housing part 11 is formed on the end surface of the stator 7 to have the same outer diameter as the bearing device support part 12c of the bearing device 12b that is fixed in contact with the end surface of the stator 7. and a vibration-proof rubber 16 is attached.

FIG. 3 is a view of the brushless electric motor according to the present invention viewed from the front in the axial direction.

FIG. 4 is a perspective view of the stator section of the brushless motor according to the present invention.

As described in detail, the configuration of the present invention eliminates the need for a sensor fixing stand, simplifies the sensor mounting work, makes the sensor magnet part smaller, and makes the bearing device smaller, resulting in a significant cost reduction effect. There is something.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of an assembled stator winding according to an embodiment of the present invention, FIG. 2 is a longitudinal half-sectional view of an internal rotor type brushless motor according to the present invention, and FIG. FIG. 4 is a perspective view of the stator portion of the brushless motor according to the present invention, and FIG. 5 is a longitudinal cross-sectional view of a conventional internal rotation type brushless motor. 1... Stator core, 2... Insulating layer, 3
...Winding, 4...Printed circuit board, 5a
...Power I CN 5 b...Drive circuit parts, 6...Hall element, 7...
・Stator, 8...Sensor magnet corresponding part, 9...
... Rotor core, 10 ... Sensor magnet, 11
...Bearing housing part, 12a, 12b...
...Bearing device, 12 c...Support part, 15
・・・・・・Stator end face cylindrical part. Name of agent Patent attorney Toshio Nakao and 1 other person 1--1 fixed, Yogin 1- Figure 3 Figure 4

Claims (2)

[Claims] (1) A ring-shaped stator core having a plurality of slots, a winding attached to the stator core through an insulating layer, and a printed circuit board on which drive circuit components and position sensors are mounted; The mounted drive circuit component is arranged in a space between the windings, and the printed circuit board is arranged so that the position sensor is located on the inner diameter side of the drive circuit component. After the windings are connected using the winding connection pattern provided on the printed circuit board, the sensing surface of the position sensor is formed thin, and a bearing device housing part is formed on the inside diameter of the printed circuit board. form,
A stator is formed by integrally molding and solidifying the stator core, windings, and printed circuit board with a thermosetting resin having electrical insulation properties, and a rotor core is provided with a permanent magnet for driving in the inner diameter of the stator. A permanent magnet for a sensor is arranged on the outer diameter part of the rotor core, and a permanent magnet for a sensor is arranged on the end face part of the rotor core, and the rotor is arranged and fixed so as to face the position sensor, and a bearing formed on the inner diameter part of the stator. A brushless electric motor comprising: a bearing device inserted and fixed into a device housing portion; and a bearing device formed in contact with the other end face portion of the stator. (2) The brushless electric motor according to claim 1, wherein a cylindrical portion is formed on the end face of the stator concentrically with the outer diameter of the bearing housing.