JP2005090379A - Electric blower - Google Patents

Abstract

An electric blower capable of suppressing shortening of the service life of a bearing is provided.
A rectifying plate 41 positioned between a motor 2 and a fan 42 is provided with a leak hole 51 that communicates the motor 2 side and the fan 42 side. By actively flowing air from the motor 2 side having a relatively large air pressure to the fan 42 side having a relatively small air pressure through the leak hole 51, the motor 2 side in the gap of the bearing 19 is moved to the fan 42 side. It is possible to suppress the leakage of air and to prevent dust and the like from entering the bearing 19, and to shorten the service life of the bearing 19.
[Selection] Figure 1

Description

  The present invention relates to an electric blower provided with a rectifying plate positioned between a motor and a fan.

Conventionally, this type of electric blower has a motor. The motor includes a motor main body having a rotation shaft, a bearing that rotatably holds the rotation shaft, and a frame as a body case that houses the motor main body and the bearing. A fan having an air inlet is attached to one end of the rotating shaft. Between the fan and the motor, a rectifying plate that rectifies the air discharged from the fan to the motor side is airtightly attached to the frame. Furthermore, the rotating shaft is provided with a through-hole that communicates the outside of the motor and the suction port of the fan in the axial direction. Then, air is sucked from the suction port by the rotation of the fan and blown out to the outer periphery of the fan. The blown air is rectified by the rectifying plate, flows into the motor, and is exhausted from the exhaust port. Further, when the air inlet is closed and the air flow is in a low air volume state, external air is sucked into the fan from the through hole, and the low air volume state is eliminated (see, for example, Patent Document 1).
JP 2002-115697 A (page 3-4, FIG. 1)

  However, in the electric blower described above, the air pressure on the fan side becomes relatively smaller than that on the motor side due to the rotation of the fan, so that the sucked air leaks from the motor side to the fan side through the clearance of the bearing. At the same time, there is a problem that dust or the like may enter the bearing and the service life of the bearing may be shortened.

  This invention is made | formed in view of such a point, and it aims at providing the electric blower which can suppress shortening of the service life of a bearing.

  The present invention provides a fan provided on a rotating shaft of a motor, a fan cover that covers the fan, a rectifying plate that is located between the motor and the fan and is attached to a body case of the motor, and the rectifying plate. And a leak hole communicating the motor side and the fan side. A rectifying plate located between the motor and the fan and attached to the body case of the motor is provided with a leak hole communicating the motor side and the fan side, so that the air pressure is relatively By actively flowing air through the leak hole to the smaller fan side, air leakage from the motor side to the fan side in the gap of the bearing is suppressed and dust and the like are prevented from entering the bearing And shortening the service life of the bearing.

  According to the present invention, by providing the rectifying plate that is located between the motor and the fan and is attached to the body case of the motor with the leak hole that communicates the motor side and the fan side, From the motor to the fan side, where air pressure is relatively low, through the leak hole, air leakage from the motor side to the fan side in the bearing gap is suppressed, and dust etc. enters the bearing This can suppress the shortening of the service life of the bearing.

  Hereinafter, the configuration of an electric blower according to an embodiment of the present invention will be described with reference to FIGS. 1 and 2.

  FIG. 1 shows an electric blower 1, and this electric blower 1 is used for, for example, a vacuum cleaner (not shown) or an industrial blower. The electric blower 1 includes a motor 2 as an electric part that is driven by electricity. The motor 2 includes a frame 3 as a substantially cylindrical body case, and a motor main body 4 accommodated in the frame 3.

  The frame 3 includes a substantially cylindrical frame main body 5 and a bridge portion 6 attached to the frame main body 5.

  The frame body 5 is formed with an opening 7 on a front end surface which is one end in the axial direction. Around the opening 7, a flange portion 8 having a substantially L-shaped cross section that protrudes all around in the radial direction is integrally provided.

  Further, a rear plate portion 9 that closes the upper end portion is integrally provided on the rear end surface that is the other end in the axial direction of the frame body 5.

  A motor head portion 11 is provided at the center of the rear plate portion 9. In the motor head portion 11, the central portion of the rear plate portion 9 projects rearward in a substantially cylindrical shape, and a bearing 12 is accommodated on the inner peripheral surface side via a bearing cap 13 and a thrust spring 14. .

  Further, a plurality of air outlets 15 serving as exhaust ports are formed in the peripheral surface near the rear portion of the frame body 5.

  The bridge portion 6 is formed in a longitudinal plate shape, and is attached to the front end portion of the frame body 5 with a screw 16 or the like so as to span a radial direction of the frame body 5 and cover a part of the opening 7.

  Further, a bearing 17 is provided in the approximate center of the bridge portion 6. The bearing 17 protrudes in the direction opposite to the frame 3 along the axial direction of the frame 3. Further, the bearing 17 includes an attachment cylinder portion 18 that protrudes in a substantially cylindrical shape toward the front, and a bearing 19 that is accommodated on the rear side that is the inner peripheral side of the attachment cylinder portion 18. These bearings 19 are ball bearings, for example, and are arranged adjacent to each other along the circumferential direction of the rotation shaft 35 of the motor main body 4. For this reason, gaps are formed between the bearings 19 adjacent to each other and the outer peripheral surface of the rotary shaft 35. A circular opening 20 is formed in the bridge portion 6.

  On the other hand, the motor body 4 includes a stator 21 that is a field as a stator, an armature 22 that is an armature as a rotor provided in the stator 21, and a pair of brush mechanism portions provided in the frame 3. Has 23.

  The stator 21 has a quadrangular stator core 24 provided in a plate shape by laminating a large number of iron plates. The stator core 24 has a substantially square insertion hole 25 into which the armature 22 is inserted at the center.

  A retainer (not shown) is attached to the insertion hole 25 of the stator core 24. A coil (not shown) is wound around the retainer so as to fit into the insertion hole 25, and by energizing these coils, a magnetic path is formed in the stator core 24 along the circumferential direction. A plurality of fixed poles, that is, an N pole and an S pole are formed on the periphery.

  Further, a pair of terminal blocks 31 formed in a substantially rectangular tube shape by an insulating member are fixed to the rear end surface of the stator core 24. These terminal blocks 31 are located in the radial direction of the frame 3 and are integrally attached to the stator core 24, respectively. Each terminal block 31 is provided with a terminal 32 connected to a household commercial AC power source (not shown) as a power source.

  One of the terminals 32 has a pair of contact plate portions 34 that come into contact with each other so as to be able to come into contact with and separate from each other while facing an insertion port 33 that opens on the surface that is an end surface of the terminal block 31. In addition, the other end of the terminal 32 is bent in a substantially L shape so that a connector provided at the tip of a power supply line (not shown) connected to a household commercial AC power source can be connected. A tip portion is provided to protrude from the insertion port 33.

  The armature 22 is coaxially provided on the inner peripheral side of the stator core 24 of the stator 21 so that the axis of the stator core 24 coincides with the axis. The armature 22 includes a rotatable rotating shaft 35. Both ends of the rotating shaft 35 are rotatably held by the bearings 12 and 19, and one end of the bearing 17 held by the bearing 19 is inserted into the mounting cylinder portion 18 of the bridge portion 6 and protrudes outside the frame 3. The frame 3 is arranged substantially coaxially. Further, a cylindrical commutator 36 having conductivity is arranged on the outer peripheral surface exposed from the stator 21 on the motor head portion 11 side of the rotating shaft 35 so that the rotating shaft 35 and the shaft center coincide with each other.

  The brush mechanism 23 is positioned in the radial direction of the frame 3 and is fixed to the frame 3 with screws or the like. The brush mechanism 23 includes a carbon brush 37 that is in sliding contact with the commutator 36 of the armature 22 and a brush holder 38 that holds the carbon brush 37.

  The brush holder 38 is supported in a state in which the longitudinal direction is substantially perpendicular to the axial direction of the rotary shaft 35 and a part of the brush holder 38 is projected to the outside of the frame 3.

  The carbon brush 37 and the commutator 36 are electrically connected to each other by being pressed by an urging means such as a spring (not shown) provided in the brush holder 38 and slidingly contacting the commutator 36. It is like that.

  On the other hand, on the front side of the bridge portion 6, that is, on the side opposite to the motor body portion 4, a rectifying plate 41 that is a diffuser as a rectifying means is provided, and a fan 42 that is a centrifugal fan rotates in front of the rectifying plate 41. It is provided as possible. That is, the rectifying plate 41 is provided between the motor 2 and the fan 42.

  The rectifying plate 41 is formed of a member such as synthetic resin, for example, and is airtightly attached to the bearing 17 of the bridge portion 6 of the frame 3 so as to close the opening 7 of the frame 3. As a result, the blower 44 is partitioned on the front side of the motor 2.

  Further, the rectifying plate 41 has a substantially disc-shaped disc portion 45 as shown in FIGS. 1 and 2. The disc portion 45 includes a body portion 48 having a circular fitting hole 47 that is airtightly fitted to the outer peripheral portion of the mounting cylinder portion 18 of the bearing 17 of the bridge portion 6 in the center portion.

  Furthermore, a round hole-shaped leak hole 51 is formed in the front end surface of the circular plate portion 45 of the rectifying plate 41 which is the portion facing the fan 42. The leak hole 51 is provided in the vicinity of the body portion 48 of the disc portion 45 of the rectifying plate 41, and along the thickness direction of the rectifying plate 41 that is the axial direction of the rotating shaft 35, that is, the front-rear direction of the electric blower 1. The disc portion 45 is provided vertically through the disc portion 45. The leak hole 51 allows the motor 2 side and the fan 42 side of the rectifying plate 41 to communicate with each other.

  A pair of screw holes 58 are formed in the body portion 48 on both sides of the fitting hole 47. Screws 59 are inserted into the screw holes 58, respectively. These screws 59 are respectively screwed to the bridge portion 6 to fix the rectifying plate 41 to the frame 3.

  Further, an arcuate wall-shaped upstream rectifying plate 61 as an upper fixed blade as a fixed blade is provided on a front end surface that is a surface facing the fan 42 of the disk portion 45. The upstream rectifying plate 61 is provided on the outer peripheral edge of the disc portion 45 substantially vertically toward the front along the axial direction of the electric blower 1 that is the axial direction of the rectifying plate 41, and on the outer periphery of the fan 42. They are located opposite each other with a predetermined gap. Further, the upstream rectifying plate 61 is provided in a plurality of plane spirals so as to be directed to the outer peripheral direction of the rectifying plate 41 along the rotation direction of the fan 42, and the guide air passage 62 continuing to the outer peripheral portion of the rectifying plate 41. Are formed.

  On the other hand, on the surface of the disc portion 45 opposite to the upstream rectifying plate 61, an arcuate wall-shaped downstream rectifying plate 63 is provided as a lower fixed wing provided substantially perpendicular to the disc portion 45. ing. The downstream rectifying plate 63 is provided in a plurality of plane spirals in the opposite direction to the upstream rectifying plate 61, and forms a passage air passage 64.

  The fan 42 is provided at an end portion on the front side of the rotation shaft 35 that is one end of the rotation shaft 35. The fan 42 is rotated by the rotation of the rotary shaft 35 by the motor 2 and sucks air from the ventilation hole 72 and blows it to the outlet 15. The heat generated by the friction with the air generated by the rotation is generated by the fan 42. It has heat resistance and is made of, for example, an aluminum alloy in consideration of inertia during rotation or mass.

  Further, the fan 42 has a lower fan plate 65 provided in a disk shape along the radial direction of the frame body 5, and is parallel to the lower fan plate 65 in the axial direction of the frame body 5 via a predetermined gap. And an upper fan plate 66 opposite to the upper fan plate 66.

  The lower fan plate 65 has a flat rear surface on the motor 2 side, and faces the front end surface of the disk portion 45 of the rectifying plate 41 substantially in parallel with a predetermined gap. Further, the lower fan plate 65 is provided with a fitting insertion hole 71 into which the rotating shaft 35 of the motor 2 is fitted and inserted in the central portion.

  The upper fan plate 66 has a ventilation hole 72 formed at the center. The upper fan plate 66 is expanded in diameter from the periphery of the ventilation hole 72 toward the lower fan plate 65.

  Further, a plurality of wall-shaped fan blades 74 that define a plurality of spiral intake air passages 73 are integrally provided between the fan plates 65 and 66. These fan blades 74 are provided in a plane spiral shape in the opposite direction to the upstream rectifying plate 61 of the rectifying plate 41.

  A substantially cylindrical fan cover 75 that covers the current plate 41 and the fan 42 is fitted to the outer peripheral portion of the flange portion 8 of the frame body 5. The fan cover 75 is formed with an air inlet 76 facing the ventilation hole 72 of the fan 42 at the center of the front surface. Further, a rear opening 77 is formed on the entire rear surface of the fan cover 75.

  Next, the operation of the above embodiment will be described.

  The electric blower 1 accommodated in the main body of the vacuum cleaner (not shown) is driven by being appropriately cleaned. The electric blower 1 is driven by the electric power supplied to the motor body 4 of the motor 2 through the brush mechanism 23 so that the motor body 4 rotates the fan 42 together with the rotating shaft 35 along the spiral direction of the fan blades 74. Let

  By the rotation of the fan 42, air is sucked from the air intake 76, and as an intake air flow into the intake air passage 73 defined by the lower fan plate 65 and the upper fan plate 66 and the fan blades 74 from the ventilation hole 72 of the fan 42. The air is blown outward toward the outer peripheral side of the fan 42.

  When the intake air flows through the intake air passage 73 in the fan 42, the intake air flows along the inner surface curved in a spiral shape of the fan blade 74, which is a surface along the direction opposite to the rotation direction of the fan 42. , Blown out from the outer periphery.

  Then, the intake air flow that has passed to the outer peripheral side of the disc portion 45 passes from the outer peripheral portion of the rectifying plate 41 to the back side of the disc portion 45, and is guided by the downstream rectifying plate 63 to pass through the inside air passage 64. The frame body of the frame 3 from the opening 7 and the circular opening 20 of the motor 2 located on the rear end surface side of the rectifying plate 41 flows in a spiral shape toward the center on the rear end surface side of the rectifying plate 41. 5 flows in.

  At the same time, air flows from the motor 2 side through the leak hole 51 to the fan 42 side where the air pressure is relatively smaller than the motor 2 side due to the rotation of the fan 42, and the front end face side of the rectifying plate 41, that is, the fan Circulate to 42 side.

  Thereafter, the air that has flowed into the frame body 5 passes through the motor body 4 while cooling, and is exhausted from the outlet 15.

  As described above, in the above-described embodiment, the disc hole 45 of the rectifying plate 41 located between the motor 2 and the fan 42 is provided with the leak hole 51 that communicates the motor 2 side and the fan 42 side. It was.

  For this reason, air should be actively flowed through the leak hole 51 from the motor 2 side where the air pressure is relatively large to the fan 42 side where the air pressure is relatively small so as not to flow as much as possible in the gap of the bearing 19. Thus, air leakage from the motor 2 side to the fan 42 side in the gap of the bearing 19 can be suppressed.

  As a result, it is possible to prevent dust such as wear powder of the carbon brush 37 from entering the bearing 19 of the bearing 17 together with air leakage from the bearing 17, thereby reducing the service life of the bearing 19 and reducing the bearing life of the bearing 17. Smooth sliding between 19 and the rotary shaft 35 can be ensured, and the reliability of the operation of the electric blower 1 can be improved.

  Further, since the leakage of air from the clearance of the bearing 19 can be suppressed simply by providing the leak hole 51 in the disc portion 45 of the rectifying plate 41, for example, in the conventional case where a relatively expensive bearing having a seal is used for the bearing Compared to the above, since a normal bearing 19 can be used, the component cost can be suppressed, and the electric blower 1 can be manufactured at low cost.

  Further, when the air inlet 76 is closed and the electric blower 1 is in a low air volume state, the air is caused to flow from the motor 2 side to the fan 42 side by the leak hole 51, whereby the friction between the air and the fan 42 is achieved. The heat can be cooled to suppress overheating on the fan 42 side, and thermal deformation of the rectifying plate 41 such as the upstream rectifying plate 61 of the rectifying plate 41 falling in the radial direction can be suppressed. It can also be prevented from being damaged by touching.

  In the above embodiment, the position where the leak hole 51 is provided may be the body portion 48 of the rectifying plate 41 or the like. In order to efficiently flow air from the motor 2 side to the fan 42 side through the leak hole 51, it is preferable to provide the leak hole 51 at a position close to the bearing 19, but in the vicinity of the bearing 19, the motor 2 side Since the mounting cylinder part 18 and the like are located, the mounting cylinder part 18 and the like are provided at a position where they are not obstructed.

  In addition, the leak hole 51 can efficiently flow air from the motor 2 side to the fan 42 side when the inner diameter size is increased, but the suction work rate of the electric blower 1 decreases as the inner diameter size is increased. The inner diameter is set in consideration of the balance with the suction power.

  Furthermore, a configuration in which a plurality of leak holes 51 are provided in the disk portion 45 of the rectifying plate 41 is also possible.

  And the detail of the electric blower 1 is not limited to the said structure.

It is the side view which notched a part which shows the electric blower of one embodiment of this invention. It is a top view which shows the baffle plate of an electric blower same as the above.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Electric blower 2 Motor 3 Frame as body case 4 Motor main-body part
19 Bearing
35 axis of rotation
41 Current plate
42 fans
51 Leak hole
75 Fan cover

Claims (1)

A motor main body having a rotating shaft, a bearing that rotatably holds the rotating shaft, and a motor including a body case that accommodates at least the bearing and the motor main body;
A fan provided at one end of the rotating shaft;
A fan cover covering this fan,
A rectifying plate located between the motor and the fan and attached to the fuselage case;
An electric blower comprising a leak hole provided on the current plate and communicating between the motor side and the fan side.

Images