JPH01164246A - Motor driven blower - Google Patents

Abstract

PURPOSE:To prevent a creeping phenomenon of the periphery of a bearing by a simple constitution by securing a metallic bearing mounting frame body at the central part of a diffuser of synthetic resin, fitting the bearing therein and supporting a rotary shaft. CONSTITUTION:A diffuser 11 of synthetic resin is mounted to one end of a motor case 1 to support one end of a rotary shaft 30, and at the same time, a centrifugal fan 32 and a fan cover 33 are provided to the outside thereof. At that time, a metallic bearing mounting frame body 23 is fixed to the central part of the diffuser 11 with a screw and so on. A bearing 24 is fitted and fixed into the inside of the frame body 23 so as to fix the rotary shaft 30. According to the constitution, even if the bearing reaches a high temperature, there is no variation in the fixed condition of the peripheral part, so that a creeping phenomenon can not be caused.

Description

[Detailed description of the invention] b) Industrial application field The present invention relates to an electric blower used in a vacuum cleaner.

(b) Conventional technology In the conventional electric blower, for example,
As shown in Publication No. 75, the rotor of the motor is pivotally supported by a motor case with one end open and a metal motor frame with the one end closed, and a diffuser and a centrifugal fan are arranged outside the motor frame. , the electric blower itself was heavy, and the vacuum cleaner was heavy.

On the other hand, Japanese Utility Model Publication No. 61-10459 discloses an electric blower that eliminates the motor frame and reduces weight by directly attaching a diffuser with a bearing for supporting the rotor of the motor that is directly fitted to the motor case. However, diffusers are usually made of resin, and the coefficient of thermal expansion of the bearing, which reaches the highest temperature during operation of the electric blower, and the fitting part of the diffuser's bearing are significantly different, and the outer circumferential part of the bearing and This has the drawback that the gap between the diffuser and the bearing fitting part becomes large, causing a creep phenomenon in which the outer peripheral part of the bearing rotates, which greatly reduces the quality of the electric blower.

(c) Problems to be Solved by the Invention The present invention has been made to solve the above-mentioned drawbacks, and has a simple structure that achieves weight reduction without causing the creep phenomenon of the outer circumference of the bearing attached to the diffuser. The technical challenge is to obtain an electric blower.

(d) Means for Solving Problems The electric blower of the present invention has a structure including a bearing mounting frame made of a metal material into which a bearing is fitted and fixed, and a bearing mounting frame made of a metal material that is fitted into a central bearing hole and screwed into the mounting frame. A fixed synthetic resin diffuser, a cylindrical motor case containing a stator and an opening at one end fixed to the rear surface of the diffuser, and a motor such that the tip of the rotating shaft protrudes onto the surface of the diffuser via the bearing. a rotor that is rotatably supported and stored in a case; a centrifugal fan located on the surface side of the diffuser and pivoted to the rotating shaft; and a fan cover that covers the centrifugal fan and is fixed to the motor case. It is characterized by having the following.

(E) Function With the above configuration, the rotor is rotatably supported by the motor case and the synthetic resin diffuser, causing the centrifugal fan to rotate at high speed, and the air sucked in by this is guided by the diffuser and flows into the motor case. After the rotor and stator are cooled, they are exhausted to the outside of the motor case.

Since both the bearing that pivotally supports the rotor and the bearing mounting frame that fits and fixes the bearing are made of metal, their thermal expansion coefficients are approximately the same, and the rotation of the rotor causes the bearing to expand. Even at high temperatures, the fit and fixation of the outer circumference of the bearing to the bearing mounting frame does not change, and the bearing does not creep, and the bearing mounting frame is fixed to the synthetic resin diffuser with screws, etc. Because there are
The bearing condition of the rotor is always maintained stably.

(f) Example Hereinafter, the structure of the electric blower of the present invention will be explained based on FIGS. 1 to 4.

Reference numeral 1 denotes a metal cylindrical motor case of an electric feeder 1LI12, which opens toward one side, has a flange portion 4 formed at one end opening 3, and has an exhaust port 5 at the rear of the cylindrical circumferential surface.
A recess 6 for a bearing is provided on the bottom surface. Reference numeral 7 denotes a substantially square motor stator press-fitted into the motor case 1, and a cooling space 8 is provided between the outer peripheral wall of the stator 7 and the inner wall of the motor case 1.
A loaf space 9 is formed in the center of the stator 7. Further, 10 is a stator winding wound around the winding holding portion of the stator 7.

Reference numeral 11 denotes a disc-shaped synthetic resin diffuser disposed in the opening 3 at one end of the motor case 1. The surface 12 of the diffuser 11 is formed into a flat plate shape, and a central bearing hole 13 is bored in the center. There is. Also this diffuser 1
1, a plurality of guide edges 1 are provided at predetermined intervals along the outer periphery in a vertical direction from the front surface 12 side to the back surface 14 side.
5... are formed, and a plurality of inclined wing parts 16... which are inclined from the front surface 12 side toward the back surface 14 side are formed on the outer surface of the guide edges 15.... The starting end portion on the surface 12 side of the inclined blade portion 16... has an inlet side blade edge 1.
6a... and the side walls 16b... are provided with an inhalation dose r:J17.... Further, on the back surface 14 of the diffuser 11, a plurality of ventilation guide vanes 18 extending from the guides 915 toward the central bearing hole 13 and curved in an arc shape are formed substantially in parallel;
A ventilation passage 19 is provided between these adjacent ventilation guide blades 18.
. . . are formed, and the ventilation passages 19 . . . communicate with the suction openings 17 . Furthermore, a plurality of support ribs 20 that fit into the motor case 1 are provided at a portion of the rear surface 14 of the diffuser 11 corresponding to the opening 3 at one end of the motor case 1 by a diameter (D) of the motor case 1. The ventilation guide blades 18 are provided so as to extend from the ventilation guide blades 18.

These support lips 20 are formed to protrude to a length that comes into contact with the stator 7 when the diffuser 11 is placed in the opening 3 at one end of the motor case 1. Further, mounting holes 22 for fixing screws 21 to the flange portion 4 are formed in appropriate inclined wing portions 16 of the diffuser 11.

Reference numeral 23 denotes a metal bearing mounting frame for mounting a bearing 24 in the central bearing hole 13 of the diffuser 11. A metal plate material is drawn to form a bearing press-fit cylinder 25, and a pair of mounting flange is provided on the periphery of the press-fit cylinder 25. Piece 26.
26, and the bearing press-fit 1#2
5, the bearing 24 is fitted and fixed by applying pressure λ, and the bearing press-fit tube 25 is fitted into the center bearing hole 13 from the back side 14, and the mounting flange pieces 26 and 26 are attached to the diffuser 1.
It is fixed to the screw hole 27 of No. 1 with a screw 28.

29 is a rotor disposed in the rotor space 9 in the motor case 1, and the rotating shaft 30 of the rotor 29 is connected to the bearing 24 attached to the diffuser 11.
The rotary shaft 30 is rotatably supported by a bearing 31 press-fitted into a bearing recess 6 of the motor case 1, and the tip of the rotating shaft 30 protrudes toward the surface 12 of the diffuser 11.

32 is a centrifugal fan that is attached to the tip of the rotating shaft 30;
R is arranged on the surface 12 side of the diffuser 11.

An arm-shaped fan cover 33 covers the centrifugal fan 32 and is fixed to the outer periphery of the flange portion 4 of the motor case 1, and has a suction port 34 bored in the center of its front surface.

With the above configuration, during the assembly work of the electric blower 2, the diffuser 11 extends its support rib 2o from the opening 3 at one end of the motor case 1 to the motor case 1.
By simply fitting the supporting ribs 2o into the inner wall of the motor case 1 and the stator 7, the support ribs 2o are securely positioned and held in the motor case 1. At this time, the bearing 24 attached to the diffuser 11 The axial center of the bearing 24 of the motor case L coincides with the axial center of the bearing 24 of the motor case L, and in this state, the mounting hole 2 is inserted into the flange portion 4.
It can be easily installed by simply fixing the screw 21 through the screw 21, which improves the installation workability.

When the electric blower 2 is driven, the rotor 29 rotates at high speed, and thereby the centrifugal fan 32 rotates at high speed. Then, air is sucked through the suction port 34 of the fan cover 33 and exhausted from the outer periphery of the centrifugal fan 32. Thereafter, the discharged air is transferred to the suction opening 17 of the diffuser 11.
... to the diffuser 11 via the inclined wing section 16...
It is divided into each ventilation path 19 formed by each ventilation guide vane 18 on the back surface 14 of the motor case 1 , and flows into the motor case 1 .
0... allows the airflow to pass through the cooling space 8 and the rotor space 9 without mixing with each other to cool the rotor 29 and the stator 7, and then from the exhaust port 5 to the motor case 1.
It is discharged to the outside, so that a portion of the motor can be efficiently cooled without causing turbulence within the motor case 1, and the suction performance can be improved.

Further, a bearing 24 that pivotally supports the rotating shaft 30 of the rotor 29, and a bearing mounting frame 23 that press-fits and fixes the bearing 24 into the bearing press-fit tube 28.
Since both are made of metal materials, their coefficients of thermal expansion are approximately the same. Therefore, even if the bearing 24 becomes hot due to the high-speed rotation of the opening 29, the fitted and fixed state of the outer circumferential portion of the bearing 24 to the bearing press-fit tube 28 will not change, and the creep phenomenon of the bearing 24 will not occur. , the mounting state of the bearing bearing 24 will not loosen. Since the bearing mounting frame 23 is fixed to the synthetic resin diffuser 11 with screws 28..., the bearing condition of the rotor 29 relative to the bearings 24, 31 is always maintained stably, and lateral vibration is prevented by the high speed rotation of the rotor 29. It never occurs.

Moreover, by attaching a synthetic resin diffuser 11 to the opening 3 at one end of the motor case l, the conventional metal plate motor frame is eliminated and the rotor 29 is reliably supported, and the diffuser 11 is lightweight. Since it is made of synthetic resin, the weight of the electric blower fa2 itself is also reduced.

(G) Effects of the Invention The present invention is constructed as described above, and in particular, a bearing is attached to a synthetic resin diffuser attached to an opening at one end of a motor case via a bearing attachment frame made of a metal material. Since both the mounting frame and the bearing are made of metal, their thermal expansion coefficients are approximately the same, so even if the bearing becomes hot due to high-speed rotation of the rotor, the bearing will not move against the bearing mounting frame. The fitted and fixed state does not change, so the creep phenomenon of the bearing does not occur, and the mounting state of the bearing does not loosen.1.Since the bearing mounting frame is fixed to the diffuser with screws, etc., the rotor It is possible to obtain an electric blower in which the bearing condition is always maintained stably and can be used for a long period of time without trouble without causing lateral vibration of the rotor.

Moreover, by directly attaching the diffuser to the motor case, the conventional motor frame made of a metal plate is abolished, and since the diffuser is made of lightweight synthetic resin, a lightweight electric blower can be obtained.

[Brief explanation of the drawing]

The drawings all relate to embodiments of the electric blower of the present invention; Fig. 1 is a partially side view, Fig. 2 is a sectional view, Fig. 3 is a view of the diffuser, and (A) is a plan view of the back side. , (b) is a plan view of the back side with the bearing mounting frame attached, (c) is a side view, and FIG. 4 is a plan view of the bearing mounting frame. 1...Motor case, 7...Stator, 11...
・Synthetic resin diffuser, 18... Ventilation guide blade, 2
0... Support rib, 23... Metal bearing mounting frame, 29... Rotor, 30... Rotating shaft, 32...
・Centrifugal fan, 33...Fan cover.

Claims (1)

[Claims] (1) A metal bearing mounting frame that fits and secures the bearing, a synthetic resin diffuser that fits the mounting frame into the central bearing hole and is fixed with screws, etc., and a stator built in, with an opening at one end. a cylindrical motor case fixed to the back surface of the diffuser; a rotor rotatably supported and supported within the motor case so that a tip of a rotating shaft projects onto the surface of the diffuser via the bearing; and a surface of the diffuser. An electric blower comprising: a centrifugal fan located on the side and pivotally attached to the rotating shaft; and a fan cover that covers the centrifugal fan and is fixed to the motor case.