CN209844706U - Sealing device and angle grinder comprising same - Google Patents

Abstract

The utility model discloses a sealing device and contain its angle mill, its interior wind channel that is used for between the epaxial rotor of motor and the stator is sealed, sealing device includes: one end of the first sealing assembly is provided with a first bulge, the first bulge is sleeved at one end of the stator, and the other end of the first sealing assembly is sleeved at a first bearing; and one end of the second sealing assembly is provided with a first flanging part, the first flanging part is sleeved at the other end of the stator, and the other end of the second sealing assembly is sleeved at the motor shaft. The first protruding portion of the first sealing assembly is sleeved at one end of the stator, the other end of the first sealing assembly is sleeved on the first bearing, the inner air channel and the outer air channel are communicated with each other through the air inlet end, the first flanging portion of the second dustproof cover is sleeved at the other end of the stator and combined with the dustproof ring, dust is prevented from entering the motor through the air outlet end, and the service life of the motor is prolonged.

Description

Sealing device and angle grinder comprising same

Technical Field

The utility model relates to a sealing device and contain its angle mill.

Background

The high-voltage brushless angle grinder comprises a shell and a motor, wherein the motor is arranged in the shell, an outer air duct for ventilation is arranged between the motor and the shell, a ventilation hole is formed in the shell, and the outer air duct dissipates heat to the motor through the ventilation hole. The motor comprises a rotor and a stator, the rotor of the motor rotates relative to the stator, a gap is reserved between the rotor and the stator, a gap is reserved between the stator and the stator, and the stator and the wire package are communicated with a rotor core, so that an inner air channel of the motor is formed, the outer air channel is communicated with the inner air channel and communicated with outside air, and when the angle grinder grinds metal, generated dust containing iron filings enters the motor through the inner air channel and is adsorbed by a permanent magnet on the rotor to damage the motor. At present, a fine gap is formed at the air inlet end of the inner air duct of the motor to prevent air containing dust from entering the inner air duct of the motor, the air outlet end of the inner air duct of the motor is set to be in an open state, and after the angle grinder is used for a long time, dust in the air can enter the inner air duct of the motor along the gap of the air inlet end and the opening of the air outlet end, so that the service life of the motor is shortened.

SUMMERY OF THE UTILITY MODEL

The to-be-solved technical problem of the utility model is to provide a sealing device and contain its angle mill in order to overcome the inside that dust in the air among the prior art can get into the motor through the air inlet end and the air-out end in the interior wind channel of motor, influence the life's of motor defect.

The utility model discloses an above-mentioned technical problem is solved through following technical scheme:

a sealing device for sealing an inner duct between a rotor and a stator on a motor shaft, the sealing device comprising:

one end of the first sealing assembly is provided with a first bulge, the first bulge is sleeved at one end of the stator, and the other end of the first sealing assembly is sleeved at a first bearing and used for blocking the communication between the air inlet end of the inner air duct and the outer air duct;

the motor shaft is provided with a first flange part, the first flange part is sleeved on the other end of the stator, the other end of the second sealing component is sleeved on the motor shaft, the second sealing component comprises a second dustproof cover and a dustproof ring, one end of the second dustproof cover is connected to the other end of the stator, the dustproof ring is located between the second dustproof cover and the fan, the dustproof ring is sleeved on the motor shaft, and the dustproof ring is far away from one end of the fan and is clamped and connected to the other end of the second dustproof cover.

In this scheme, the angle grinder includes motor and casing, and the motor sets up inside the casing, is provided with the outer wind channel with outside intercommunication between motor and casing, also has the wind channel of ventilation between the stator of motor and rotor, and this wind channel is the interior wind channel of motor, and outer wind channel and interior wind channel communicate mutually and communicate in the outside, and outer wind channel and interior wind channel have the same air inlet end and air-out end. The stator is close to the one end of fan and is the air-out end, and the stator is close to the one end of first bearing and is the air inlet end.

Because of the interior wind channel that dust in the air mainly got into the motor through air inlet end and air-out end, connect first seal assembly in the one end that the stator is located the air inlet, block interior wind channel and outer wind channel intercommunication, set up the one end that the second seal assembly is located the air-out at the stator, through the mode of second shield and dust ring joint, block inside dusty air gets into the motor, protected the motor, improved the life of motor.

Preferably, the first sealing assembly includes a first dust cap, the first dust cap is disc-shaped, a circular hole for the rotor to pass through is formed in the center of the disc, one side surface of the first dust cap abuts against one side surface of the stator, the first protruding portion extending outwards in the direction toward the stator is formed in the outer peripheral surface of the first dust cap, the first protruding portion is sleeved on the end portion of the stator, the first sealing assembly further includes a bearing chamber, the bearing chamber is cylindrical, one end of the bearing chamber is sleeved on the outside of the first bearing, the other end of the bearing chamber abuts against the other side surface of the first dust cap, and the first dust cap and the bearing chamber enclose an area for blocking the inner air duct from communicating with the outer air duct at the air inlet end.

In this scheme, the one end of stator is located to first bellying cover, blocks that the clearance entering motor inside of dusty air through the junction of first shield and stator. First shield is discoid structure, and the one end of bearing room supports and leans on in the side of first shield, blocks the interior wind channel of motor at the air inlet end with outer wind channel, has avoided the inside that dusty air passes through air inlet end entering motor, has improved the life of motor.

Preferably, the first sealing assembly further comprises a sealing ring, the sealing ring is located between the first dust cover and the bearing chamber, the sealing ring is made of an elastic material, and two side surfaces of the sealing ring respectively abut against the first dust cover and the bearing chamber.

In this scheme, set up the sealing ring of elasticity material between first shield and bearing room, first shield, sealing ring and bearing room three compress tightly through the axial, can reach better sealed effect.

Preferably, the inner circumferential surface of the circular hole is provided with a second protruding portion extending outwards in a direction away from the stator, and the sealing ring is sleeved on the second protruding portion.

In this scheme, locate the second bellying with the sealing ring cover, can fix the sealing ring, when avoiding the angle mill operation, the sealing ring drops.

Preferably, a fastening portion extending outward in the radial direction of the first dust cover is arranged at an end portion, away from the stator, of the second protruding portion, and one side surface of the sealing ring abuts against the fastening portion.

In this scheme, form an annular groove between clamping part and the first shield, this annular groove is gone into to the sealing ring card, can further improve the fixed effect of sealing ring, avoids the sealing ring to drop.

Preferably, a first through hole for a cable to pass through is formed in the side face of the first dust cover, third protruding portions are arranged on the periphery of the first through hole, the first sealing assembly further comprises a sealing element, one end of the sealing element is sleeved on the cable, and the other end of the sealing element is sleeved on the third protruding portions.

In this scheme, the cable mainly includes control line and power cord, consequently sets up first through-hole on first shield and supplies the cable to pass, is equipped with the third bellying all around of first through-hole, and the sealing member is the pyrocondensation pipe, and the cable is entangled to the third bellying other end in the one end cover of pyrocondensation pipe, and through the pyrocondensation pipe shrink during the installation, can seal first through-hole, also can select to fill sealing material between the cable as required, overlaps the pyrocondensation pipe again and seals. In other alternatives, the sealing member may be made of other sealing materials with shrinking property according to the requirement.

Preferably, a plurality of connection holes are formed in the side surface of the first dust cover at intervals along the circumferential direction of the disk, and the first sealing assembly further includes a plurality of screws, each of which is inserted into each of the connection holes and connected to the end of the stator.

In this scheme, pass through bolted connection with first shield and stator, when avoiding the angle mill to use, first shield drops from the stator tip, influences sealed effect.

Preferably, the second dust cover is disc-shaped, a second round hole through which the rotor passes is formed in the center of the second dust cover, the first flanging portion extending outward in the direction toward the stator is formed in the outer peripheral surface of the second dust cover, the first flanging portion is sleeved on the other end portion of the stator, a second flanging portion extending outward in the direction away from the stator is formed in the inner peripheral surface of the second round hole, and the second flanging portion is connected to one side surface of the dust ring in a clamping manner.

In this scheme, the second shield is discoid structure, and the one end that the stator is located the air-out is located to the first turn-ups portion cover of second shield, and the other end of second shield is equipped with second turn-ups portion, encloses into an area through second shield, second turn-ups portion and dust ring, has sealed the air-out end in the interior wind channel of motor, blocks the inside that dust got into the motor from the air-out end in interior wind channel.

Preferably, a first annular groove is formed in one side face, facing the stator, of the dust ring, the second flanging portion is clamped in the first annular groove, a gap is formed in the clamping connection portion, the gap is used for avoiding mutual friction when the dust ring rotates relative to the second flanging portion, and the gap is of a U-shaped rotary structure along the center of the motor shaft and used for blocking dust from entering the inner air duct.

In the scheme, the dustproof ring is sleeved on the motor shaft and rotates along with the motor, therefore, the second annular groove is arranged on the dustproof ring and is connected with the second flanging part in a clamping mode, a gap is reserved at the clamping connection position, the gap is prevented from being rubbed with the second flanging part when the dustproof ring rotates, and the smaller the gap is, the better the gap is. The second dust cover, the second flanging part and the dust ring form a U-shaped labyrinth structure, so that the inner air duct and the outer air duct of the motor are well isolated in the air outlet end, the dust-proof effect of the motor at the air outlet end is further improved, the motor is protected, and the service life of the motor is prolonged.

The utility model provides an angle grinder, angle grinder includes motor and casing, the motor set up in the inside of casing, the casing with be equipped with the outer wind channel that the air feed passes through between the motor, be provided with on the casing with the ventilation hole of outer wind channel and outside intercommunication, the motor includes motor shaft, stator and rotor, the motor shaft is worn to locate the stator with the rotor, the stator cover is located the outside of rotor, just the stator with be equipped with the interior wind channel that the air feed passes through between the rotor, outer wind channel with interior wind channel communicates each other, angle grinder still includes foretell sealing device, sealing device connect in the both ends of stator.

In this scheme, sealing device connects on the inside motor of angle mill, and mainly used protects the stator and the rotor of motor, reduces the interior wind channel that dust in the air got into the motor, improves the life of motor.

On the basis of the common knowledge in the field, the above preferred conditions can be combined at will to obtain the preferred embodiments of the present invention.

The utility model discloses an actively advance the effect and lie in: the first protruding portion of the first sealing assembly is sleeved at one end of the stator, the other end of the first sealing assembly is sleeved on the first bearing, the inner air channel and the outer air channel are communicated with each other through the air inlet end, the other end of the stator is sleeved with the first flanging portion of the second dustproof cover and combined with the dustproof ring, dust is prevented from entering the motor through the air outlet end, the motor is protected, and the service life of the motor is prolonged.

Drawings

Fig. 1 is a schematic structural diagram of a sealing device according to a preferred embodiment of the present invention.

Fig. 2 is a partial structural schematic view of a sealing device according to a preferred embodiment of the present invention.

Description of reference numerals:

motor shaft 10

Rotor 20

Stator 30

Cable 40

Fan 50

Inner air duct 60

Outer air duct 70

Housing 80

First bearing 90

First seal assembly 1

First dust cover 11

First convex portion 111

Second boss 112

Latch 113

Connecting hole 114

First through hole 115

Third boss 116

Sealing ring 12

Bearing chamber 13

Screw 14

Sealing element 15

Second seal assembly 2

Second dust cover 21

First burring 211

Second flanging part 212

Dust ring 22

First annular groove 221

Gap 23

Detailed Description

The present invention will be more clearly and completely described below by way of examples and with reference to the accompanying drawings, but the present invention is not limited thereto.

As shown in fig. 1 and 2, the present embodiment discloses a sealing device for sealing an inner duct 60 between a rotor 20 and a stator 30 on a motor shaft 10, the sealing device including: a first sealing assembly 1, wherein one end of the first sealing assembly 1 is provided with a first protruding part 111, the first protruding part 111 is sleeved at one end of the stator 30, and the other end of the first sealing assembly 1 is sleeved at the first bearing 90 for blocking the communication between the inner air duct 60 and the outer air duct 70 at the air inlet end; second seal assembly 2, the one end of second seal assembly 2 is equipped with first turn-ups portion 211, the other end of stator 30 is located to first turn-ups portion 211 cover, and motor shaft 10 is located to the other end cover of second seal assembly 2, second seal assembly 2 includes second shield 21 and dust ring 22, the one end of second shield 21 is connected in the other end of stator 30, dust ring 22 is located between second shield 21 and fan 50, motor shaft 10 is located to the dust ring 22 cover, the one end block that fan 50 was kept away from to dust ring 22 is connected in the other end of second shield 21.

In this embodiment, the angle grinder includes a motor and a housing 80, the motor is located inside the housing 80, an outer air duct 70 communicated with the outside is provided between the motor and the housing 80, a ventilation air duct is also provided between the stator 30 and the rotor 20 of the motor, the air duct is an inner air duct 60 of the motor, the outer air duct 70 and the inner air duct 60 are communicated with each other and communicated with the outside, and the outer air duct 70 and the inner air duct 60 have the same air inlet end and air outlet end. The end of the stator 30 close to the first bearing 90 is an air inlet end, and the end of the stator 30 close to the fan 50 is an air outlet end.

Because of the interior wind channel 60 of dust in the air mainly gets into the motor through air inlet end and air-out end, connect first seal assembly 1 in the one end that stator 30 is located the air inlet, block interior wind channel 60 and outer wind channel 70 intercommunication, set up the one end that stator 30 is located the air-out with second seal assembly 2, through the mode that second shield 21 and dirt proof ring 22 block are connected, block inside the dust-laden air gets into the motor, the motor has been protected, the service life of motor has been improved.

First seal assembly 1 includes first shield 11, first shield 11 is discoid, the center of disc is equipped with the round hole that supplies rotor 20 to pass, a side of first shield 11 supports and leans on in a side of stator 30, be equipped with on the outer peripheral face of first shield 11 along the outside first bellying 111 that extends of the direction towards stator 30, the tip in stator 30 is located to first bellying 111 cover, first seal assembly 1 still includes bearing chamber 13, bearing chamber 13 is cylindric structure, 90 outsides of first bearing are located to one pot head of bearing chamber 13, the other end of bearing chamber 13 supports and leans on in the another side of first shield 11, first shield 11 and bearing chamber 13 enclose into an area, be used for blocking interior wind channel 60 and outer wind channel 70 intercommunication at the air inlet end.

In this embodiment, the first protrusion 111 is sleeved at one end of the stator 30 to block dust-containing air from entering the motor through a gap at a connection between the first dust cover 11 and the stator 30. First shield 11 is discoid structure, and the one end of bearing room 13 supports and leans on in the side of first shield 11, and first shield 11 and bearing room 13 enclose into a closed interval, blocks the interior wind channel 60 of motor at the air inlet end with outer wind channel 70, has avoided the inside that dusty air passes through the air inlet end and gets into the motor, has improved the life of motor.

The first sealing assembly 1 further includes a sealing ring 12, the sealing ring 12 is made of an elastic material, and two side surfaces of the sealing ring 12 respectively abut against the first dust cover 11 and the bearing chamber 13.

In this embodiment, the sealing ring 12 made of an elastic material is disposed between the first dust cap 11 and the bearing chamber 13, and the first dust cap 11, the sealing ring 12 and the bearing chamber 13 are axially compressed, so that a good sealing effect can be achieved.

The inner circumferential surface of the circular hole of the first dust cover 11 is provided with a second protrusion 112 extending outward along a direction away from the stator 30, and the second protrusion 112 is sleeved with the sealing ring 12.

In the embodiment, the sealing ring 12 is sleeved on the second protrusion 112, so that the sealing ring 12 can be fixed, and the sealing ring 12 is prevented from falling off during the operation of the angle grinder.

The end of the second protruding portion 112 away from the stator 30 is provided with a buckling portion 113 extending outward along the radial direction of the first dust cover 11, and one side surface of the sealing ring 12 abuts against the buckling portion 113.

In this embodiment, an annular groove is formed between the fastening portion 113 and the first dust cover 11, and the sealing ring 12 is fastened into the annular groove, so that the fixing effect of the sealing ring 12 can be further improved, and the sealing ring 12 is prevented from falling off.

The side of the first dust cover 11 is provided with a first through hole 115 for the cable 40 to pass through, a third protrusion 116 is arranged around the first through hole 115, the first sealing assembly 1 further includes a sealing member 15, one end of the sealing member 15 is sleeved on the cable 40, and the other end of the sealing member 15 is sleeved on the third protrusion 116.

In this embodiment, the cable 40 mainly includes a control line and a power line, so that the first through hole 115 is disposed on the first dust cover 11 for the cable 40 to pass through, the third protrusion 116 is disposed around the first through hole 115, the sealing member 15 is a heat shrink tube, one end of the heat shrink tube is sleeved on the other end of the third protrusion 116 to sleeve the cable 40, and when the cable is installed, the heat shrink tube shrinks to seal the first through hole 115, or a sealing material is filled between the cables 40 according to requirements, and then the heat shrink tube is sleeved to seal. In other alternative embodiments, the sealing member 15 may be made of other sealing materials with shrinking property according to the requirement.

The side surface of the first dust cover 11 is provided with a plurality of connection holes 114 at intervals along the circumferential direction of the disk, and the first sealing assembly 1 further comprises a plurality of screws 14, each screw 14 penetrates through each connection hole 114 and is connected to the end of the stator 30.

In the embodiment, the first dust cover 11 is connected with the stator 30 through the screw 14, so that the first dust cover 11 is prevented from falling off from the end part of the stator 30 to influence the sealing effect when the angle grinder is used.

The second dust cover 21 is disc-shaped, a second circular hole for the rotor 20 to pass through is formed in the center of the second dust cover 21, a first flanging portion 211 extending outward in a direction toward the stator 30 is formed in the outer peripheral surface of the second dust cover 21, the other end portion of the stator 30 is sleeved with the first flanging portion 211, a second flanging portion 212 extending outward in a direction away from the stator 30 is formed in the inner peripheral surface of the second circular hole, and the second flanging portion 212 is connected to one side surface of the dust ring 22 in a clamping manner.

In this embodiment, the second dust cap 21 is a disc-shaped structure, and the first flanging portion 211 of the second dust cap 21 is sleeved at one end of the stator 30, which is located at the air outlet, so as to prevent the dust-containing air from entering the motor through the gap at the connection position of the second dust cap 21 and the stator 30. The other end of the second dust cover 21 is provided with a second flanging part 212, and an area is enclosed by the second dust cover 21, the second flanging part 212 and the dust ring 22, so that the air outlet end of the inner air duct 60 of the motor is also sealed, and dust is prevented from entering the motor from the air outlet end of the inner air duct 60.

A first annular groove 221 is formed in one side surface of the dust-proof ring 22 facing the stator 30, the second flanging part 212 is clamped in the first annular groove 221, a gap 23 is formed at the clamping connection position, the gap 23 is used for avoiding mutual friction when the dust-proof ring 22 rotates relative to the second flanging part 212, and the gap 23 is of a U-shaped rotary structure along the center of the motor shaft 10 and used for preventing dust from entering the inner air duct 60.

In the embodiment, the dust ring 22 is sleeved on the motor shaft 10 and rotates with the motor, so that the second annular groove is provided on the dust ring 22 to be engaged with the second flanging part 212, and a gap 23 is reserved at the engaging position, and the gap 23 prevents the dust ring 22 from rubbing against the second flanging part 212 when rotating. The second dust cover 21, the second flanging part 212 and the dust ring 22 form a U-shaped labyrinth structure, so that the inner air duct 60 and the outer air duct 70 of the motor are well isolated in the air outlet end, the dust-proof effect of the motor at the air outlet end is further improved, the motor is protected, and the service life of the motor is prolonged.

The utility model provides an angle grinder, angle grinder includes motor and casing 80, the motor sets up in the inside of casing 80, be equipped with the outer wind channel 70 that the air feed passes through between casing 80 and the motor, be provided with the ventilation hole with outer wind channel 70 and outside intercommunication on the casing 80, the motor includes motor shaft 10, stator 30 and rotor 20 are worn to locate by motor shaft 10, the outside of rotor 20 is located to stator 30 cover, and be equipped with the interior wind channel 60 that the air feed passes through between stator 30 and the rotor 20, outer wind channel 70 and interior wind channel 60 communicate mutually, angle grinder still includes foretell sealing device, sealing device connects in the both ends of stator 30.

In the embodiment, the sealing devices are connected to two ends of the stator 30 inside the angle grinder, and are mainly used for protecting the stator 30 and the rotor 20 of the motor, reducing dust in air from entering the inner air duct 60 of the motor, and prolonging the service life of the motor.

Although specific embodiments of the present invention have been described above, it will be understood by those skilled in the art that this is by way of example only and that the scope of the invention is defined by the appended claims. Various changes and modifications to these embodiments may be made by those skilled in the art without departing from the spirit and the principles of the present invention, and these changes and modifications are all within the scope of the present invention.

Claims (10)

1. A sealing device for sealing an inner duct between a rotor and a stator on a motor shaft, the sealing device comprising:

one end of the first sealing assembly is provided with a first bulge, the first bulge is sleeved at one end of the stator, and the other end of the first sealing assembly is sleeved at a first bearing and used for blocking the communication between the air inlet end of the inner air duct and the outer air duct;

the motor shaft is provided with a first flange part, the first flange part is sleeved on the other end of the stator, the other end of the second sealing component is sleeved on the motor shaft, the second sealing component comprises a second dustproof cover and a dustproof ring, one end of the second dustproof cover is connected to the other end of the stator, the dustproof ring is located between the second dustproof cover and the fan, the dustproof ring is sleeved on the motor shaft, and the dustproof ring is far away from one end of the fan and is clamped and connected to the other end of the second dustproof cover.

2. The sealing device of claim 1, wherein the first seal assembly includes a first dust cap, the first dustproof cover is disc-shaped, a round hole for the rotor to pass through is formed in the center of the disc, one side surface of the first dustproof cover is abutted against one side surface of the stator, the peripheral surface of the first dustproof cover is provided with the first bulge part which extends outwards along the direction towards the stator, the first bulge part is sleeved at the end part of the stator, the first sealing assembly further comprises a bearing chamber, the bearing chamber is cylindrical, one end of the bearing chamber is sleeved on the first bearing, the other end of the bearing chamber is abutted against the other side surface of the first dustproof cover, the first dustproof cover and the bearing chamber are enclosed to form an area for blocking the inner air duct from being communicated with the outer air duct at the air inlet end.

3. The seal arrangement of claim 2, wherein the first seal assembly further comprises a seal ring positioned between the first dust cover and the bearing chamber, the seal ring being resilient, the seal ring having two sides that abut the first dust cover and the bearing chamber, respectively.

4. The sealing device as claimed in claim 3, wherein the circular hole has a second protrusion extending outward in a direction away from the stator on an inner circumferential surface thereof, and the sealing ring is fitted over the second protrusion.

5. The sealing device according to claim 4, wherein an end of the second protruding portion away from the stator is provided with a buckling portion extending outward in a radial direction of the first dust cover, and a side surface of the sealing ring abuts against the buckling portion.

6. The sealing device according to claim 2, wherein a first through hole for a cable to pass through is formed in a side surface of the first dust cover, a third protrusion portion is formed around the first through hole, the first sealing assembly further comprises a sealing member, one end of the sealing member is sleeved on the cable, and the other end of the sealing member is sleeved on the third protrusion portion.

7. The sealing device according to claim 2, wherein the side surface of the first dust cap is provided with a plurality of connection holes at intervals along the circumferential direction of the disk, and the first sealing assembly further comprises a plurality of screws, each screw passing through each of the connection holes and being connected to an end of the stator.

8. The sealing device according to claim 1, wherein the second dust cover has a disk shape, a second circular hole is provided at a center of the second dust cover for the rotor to pass through, the first burring portion extending outward in a direction toward the stator is provided on an outer circumferential surface of the second dust cover, the first burring portion is fitted over the other end portion of the stator, a second burring portion extending outward in a direction away from the stator is provided on an inner circumferential surface of the second circular hole, and the second burring portion is engaged with one side surface of the dust ring.

9. The sealing device according to claim 8, wherein a side surface of the dust ring facing the stator is provided with a first annular groove, the second flanged portion is clamped in the first annular groove, and a gap is formed at the clamping joint, the gap is used for avoiding mutual friction when the dust ring rotates relative to the second flanged portion, and the gap is of a U-shaped revolution structure along the center of the motor shaft and used for blocking dust from entering the inner air duct.

10. An angle grinder, the angle grinder includes motor and casing, the motor set up in the inside of casing, the casing with be equipped with the outer wind channel that the air feed passes through between the motor, be provided with on the casing with the ventilation hole of outer wind channel and outside intercommunication, the motor includes motor shaft, stator and rotor, the motor shaft wears to locate the stator with the rotor, the stator cover is located the outside of rotor, just be equipped with the interior wind channel that the air feed passes through between stator and the rotor, outer wind channel with interior wind channel is mutually linked together, its characterized in that, the angle grinder still includes sealing device as in any one of claims 1-9, sealing device connect in the both ends of stator.