JP2001078381A - Dc brushless motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide waterproofing property for a motor itself by mounting a doughnut-type printed circuit board near a cylindrical housing pressingly fitted to the opening of a cylindrical bottomed stainless case so as to form a bearing part, a case press-fit part, and the cable taking-out part of the printed circuit board into a waterproof structure. SOLUTION: A cylindrical stator 2 formed so that a coil may be wound and epoxy resin may be electrophoretic coated is pressingly fitted to a cylindrical bottomed stainless motor exterior case 1. A rotor 3 turnably supported by a ball bearing 4 pressingly fitted to the bottom of the motor exterior case 1 and a sealed bearing 5 pressingly fitted into a housing 9 is inserted and mounted in a stator A web washer 6 is disposed between the bearing 4 and the motor exterior case 1, and the rotor 3 is biased the housing 9 so as to prevent rattle in a motor shaft direction, thereby rotating the motor smoothly. The sealed bearing 5 is formed into the sealed structure of lubricating oil by means of a seal member of synthetic rubber between inner and outer laces, and the cable taking-out part is inserted into the waterproof housing 13.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a waterproof structure of a DC brushless motor, and more particularly to a DC brushless motor suitable for application to a pump of a bath water circulation device.

[0002]

2. Description of the Related Art Conventionally, when a direct current brushless motor is used as a circulation pump of a bath water circulation device, a vertically arranged spiral pump is used to prevent bath water from entering the motor from the pump section. With a horizontal type circulation pump, for example, the motor part and the pump part are completely separated like a magnet pump, or the motor is completely molded with resin like a canned pump, and water flows from the shaft part to the inside of the motor. The one configured so as not to penetrate is adopted.

[0003]

In such a conventional pump, not only the method of mounting the pump is limited, but also because of its unique structure, the pump itself becomes large,
There is a problem that the versatility of the pump motor is reduced and the cost is increased. In addition, the above-mentioned pumps, etc., which take into account the ingress of water from the pump section to the motor section, do not consider much about the waterproofness of the motor section, and the pump can be directly flooded or submerged. There is also a problem that it cannot be installed in places with sexual characteristics. The present invention has been made in order to solve the above-described problems, and a motor shaft portion of a DC brushless motor, an outer case and a cable take-out portion are each provided with a waterproof structure, without increasing the size and cost. Can be directly flooded,
Provided is a DC brushless motor used for a circulating pump that can be installed in a place where there is a possibility of submersion.

[0004]

Means for Solving the Problems and Action / Effect To attain the above object, a first aspect of the present invention is a cylindrical stainless steel case having a bottom and a substantially cylindrical housing press-fitted into the case opening. A DC brushless motor having a substantially donut-shaped printed board near the housing inside the case, wherein the printed circuit board is provided on the motor rotating shaft bearing part on the housing side, the case press-fitting part of the housing, and the housing. A waterproof structure is provided at the cable outlet. If the motor is hermetically configured, the places where water can enter the motor are the part where the motor shaft passes through the housing, the joint of the outer case, and the coil from the motor or the cable from the printed circuit board. Is a part that takes out the housing from the housing, and applies a waterproof structure to all of them to make the motor itself waterproof, and to a circulating pump that can be installed directly in places where there is a possibility of being directly submerged or submerged It enables the application of

[0005] The second aspect of the present invention relates to a waterproof structure of a motor rotating shaft bearing portion on a housing side as a waterproof bearing.
It is characterized in that a sealed ball bearing is arranged. Sealed ball bearings have a structure in which a seal is placed between the inner race and the outer race to seal the lubricating oil.However, when the bearing is wet or the motor is submerged and the water pressure is relatively low, the seal is used. This allows for waterproofing.

A third aspect of the present invention is characterized in that an O-ring is press-fitted between the front surface of the waterproof bearing and the housing. Since the front surface of the bearing and the housing are press-contacted with each other, the motor is formed through a very small gap between the housing and the bearing. Prevention of intrusion of water into the interior can be made more reliable.

A fourth aspect of the present invention is characterized in that a flange is projected from a rear end of the outer ring of the waterproof bearing. When the bearing is inserted into the housing, the flange provided at the rear end of the outer ring of the bearing abuts the housing, so that the gap between the housing and the front surface of the bearing is uniform, so that the O-ring is uniformly compressed. And stable water resistance can be ensured.

According to a fifth aspect of the present invention, an O-ring is inserted between the outer peripheral surface of the waterproof bearing and the housing as a waterproof structure of the motor rotating shaft bearing portion on the housing side. The inserted O-ring is compressed by the housing and the bearing and is in close contact with both, so that water can be prevented from entering the motor through a very small gap between the bearing and the housing.

According to a sixth aspect of the present invention, an O-ring is interposed between the outer peripheral surface of the housing and the inner peripheral surface of the case as a waterproof structure of the case press-fitting portion of the housing. The case is cylindrical with a bottom, and the housing is press-fitted to form a hermetic seal. By arranging an O-ring at the press-fitted portion and closely contacting the case and the housing, the portion can be waterproofed. .

According to a seventh aspect of the present invention, an ultraviolet curable resin is applied to the open end of the case and an outer peripheral portion of the housing.
The waterproof structure of the housing press-fit portion can be made more reliable.

In a preferred embodiment of the present invention, the waterproof structure of the cable outlet includes a waterproof housing having a substantially inverted hat-shaped cross section to be inserted into a recess having an opening in the housing and having a hole at the bottom for inserting a cable. A rubber bush that is housed in the housing and through which a cable is inserted, a pressing plate having a substantially flat plate-shaped hole through which the cable is inserted and fixed to the housing via rubber packing to seal the rubber bush into the waterproof housing; The present invention is characterized in that it is made of an ultraviolet effect resin applied to a cable insertion portion of a plate, and can realize waterproofing of a cable extraction portion.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION In order to further clarify the configuration and operation of the present invention described above, a preferred embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a sectional view showing the structure of a DC brushless motor according to one embodiment of the present invention. FIG. 2 is a sectional view showing the structure of the present invention, the third and fourth aspects of the present invention. The motor is constituted by an inner rotor type brushless DC motor. That is, in the motor, a coil is wound around a stainless steel motor outer case 1 having a bottom, and a substantially cylindrical stator 2 coated with an electrodeposition of an epoxy resin is press-fitted and fixed. Ball bearing 4 and housing 9 press-fit into the bottom of outer case 1
The rotor 3 is rotatably supported by a sealed ball bearing 5 which is press-fitted into the shaft.

A wave washer 6 is interposed between the ball bearing 4 and the motor outer case 1 to urge the rotor 3 toward the housing 9 to prevent rattling of the motor shaft in the axial direction. , Realizes smooth rotation of the motor. The hermetically sealed ball bearing 5, which is press-fitted into the housing 9, has a structure in which lubricating oil is sealed between the inner race and the outer race of the bearing by a sealing member made of synthetic rubber or the like. Water is prevented from entering the motor when voltage is applied. Further, an O-ring 8 is interposed between the outer ring of the bearing 5 and the housing 9. The O-ring 8 is compressed by the bearing 5 and the housing 9 to be in close contact with both. Can be completely prevented from entering. As another embodiment of the portion, a structure shown in FIG. 2 will be described. The embodiment shown in FIG. 2 is an example in which an O-ring is press-contacted between the front surface of the bearing 5 and the housing 9. Prevents water from entering. In addition, a flange is provided at the rear end of the bearing outer ring, and the flange is pressed into the housing so that the gap between the front surface of the bearing and the housing can be made uniform. This not only improves performance, but also eliminates variations in waterproof performance of each motor.

The motor outer case 1 made of stainless steel.
A housing 9 made of an aluminum alloy is press-fitted into the opening via an O-ring 7 for heat dissipation and light weight, thereby sealing the motor and ensuring waterproofness of the press-fitted portion. After the press-fitting, an ultraviolet curable resin 10 which is more workable in application and curing than the other sealant is applied and cured between the outer periphery of the housing 9 and the opening end of the motor outer case 1 to ensure more waterproofness. And

Next, the structure of the cable outlet provided in the housing 9 will be described. A waterproof housing 13 having a substantially inverted hat shape in cross section and having a hole through the bottom of the housing 9 is inserted into a recess having an opening formed in a substantially rectangular shape of the housing 9. A substantially doughnut-shaped printed circuit board, a waterproof housing 13, a rubber bush 11, a pressing plate 14, a cable, which is installed inside the motor by using a waterproof housing 13 without directly drilling a hole for cable insertion in the housing 9, A sub-assembly of the connector that does not need to be performed is possible, and the assembling workability of the motor is greatly improved. A rubber bush 11 through which a cable is inserted is housed in a concave portion of the waterproof housing 13, and a substantially flat holding plate 14 having a hole through which a cable is inserted so as to cover the waterproof housing and the rubber bush is provided via a rubber packing 12. It is fixed to the housing 9 by screws (not shown). Since the holding plate 14 is fixed to the housing 9 via the rubber packing, it is possible to prevent water from entering the inside of the motor from between the holding plate and the housing. The rubber bush 11 is set to be sufficiently compressed when the holding plate is fixed, and at the same time it comes into close contact with the cable as well as the holding plate 14, so that the space between the holding plate 14 and the rubber bush 11 and the rubber bush 11 It can ensure waterproofness between the cables. Further, after the holding plate 14 is fixed, the periphery of the cable insertion hole of the holding plate 14 is covered with the ultraviolet curing resin 10, so that more reliable waterproofness can be obtained. As described above, by applying a waterproof structure to each of the outer case, shaft take-out part, and cable take-out part of the motor, a DC brushless motor applicable to a circulating pump installed in places where there is a possibility of being wet or submerged Can be obtained.

[Brief description of the drawings]

FIG. 1 is a sectional view of a motor according to an embodiment of the present invention.

FIG. 2 is a sectional view according to an embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Motor exterior case 2 ... Stator 3 ... Rotor 4 ... Ball bearing 5 ... Sealed ball bearing 6 ... Wave washer 7 ... O-ring 8 ... O-ring 9 ... Housing 10 ... Ultraviolet curing resin 11 ... Rubber bush 12 ... Rubber packing 13 ... Waterproof housing 14 ... Presser plate

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Kiyofumi Fujii 2-1-1 Nakajima, Kokurakita-ku, Kitakyushu-shi, Fukuoka Tochiki Kiki Co., Ltd. (72) Katsumi Sakamoto 2 Nakajima, Kokurakita-ku, Kitakyushu-shi, Fukuoka F-term (reference) No. 1-1, TOTO Kiki Co., Ltd. 5H019 CC03 FF03 5H605 AA02 BB09 BB17 CC03 CC04 CC06 CC10 DD16 DD32 DD36 EB31 EB34 EC02 EC18

Claims (8)

[Claims] 1. A DC brushless motor having a bottomed cylindrical stainless steel case and a substantially cylindrical housing press-fitted and fixed in the case opening, and a substantially donut-shaped print near the housing inside the case. A direct current brushless motor comprising a substrate, wherein a waterproof structure is provided at a motor rotating shaft bearing portion on a housing side, a case press-fitting portion of the housing, and a cable extracting portion of a printed circuit board provided on the housing. 2. The DC brushless motor according to claim 1, wherein a sealed ball bearing is disposed as a waterproof bearing in the waterproof structure of the motor rotating shaft bearing portion on the housing side. 3. An O-ring is disposed between the front surface of the waterproof bearing and the housing by pressure contact.
DC brushless motor as described. 4. The DC brushless motor according to claim 3, wherein a flange is provided at a rear end of the outer ring of the waterproof bearing. 5. The brushless DC motor according to claim 2, wherein an O-ring is inserted between the outer peripheral surface of the waterproof bearing and the housing as a waterproof structure of the motor rotating shaft bearing portion on the housing side. 6. The brushless DC motor according to claim 1, wherein an O-ring is inserted between an outer peripheral surface of the housing and an inner peripheral surface of the case as a waterproof structure of the case press-fitting portion of the housing. . 7. The DC brushless motor according to claim 1, wherein an ultraviolet curable resin is applied to the case opening end and an outer peripheral portion of the housing. 8. A waterproof housing having a substantially inverted hat-shaped cross-section inserted into a recess having an opening in the housing and having a hole through which a cable is inserted at the bottom, wherein the waterproof housing has a waterproof structure. A rubber bush in which a cable is housed, a rubber plate, a holding plate having a substantially flat hole fixed to the housing via rubber packing to seal the rubber bush in a waterproof housing, and a hole for inserting the cable, and a cable of the holding plate 2. The device according to claim 1, wherein the insertion portion is made of an ultraviolet ray effect resin.
8. A DC brushless motor according to any one of claims 1 to 7.