Canned motor and vacuum pump

Patent metadata

Field	Value
Publication number	US-9614411-B2
Application number	US-201313853005-A
Country	US
Kind code	B2
Filing date	Mar 28, 2013
Priority date	Mar 29, 2012
Publication date	Apr 4, 2017
Grant date	Apr 4, 2017

Abstract

Provided is a canned motor to be coupled to a vacuum pump and used as a rotary driving source for the vacuum pump. The canned motor includes: a stator core; a rotor provided on an inner side of the stator core; and a non-conductive can provided between the stator core and the rotor. The non-conductive can is configured to separate the stator core and the rotor from each other. The non-conductive can is made of resin, ceramic, or composite material thereof. The non-conductive can is bonded to the stator core with an adhesive.

First claim

What is claimed is:

1. A canned motor to be coupled to a vacuum pump and used as a rotary driving source for the vacuum pump, the canned motor comprising:
a stator core;
a rotor provided on an inner side of the stator core; and
a non-conductive can provided between the stator core and the rotor, the non-conductive can being configured to separate the stator core and the rotor from each other in a state in which the non-conductive can is held in contact with the stator core, the non-conductive can being made of resin, ceramic, or composite material thereof, wherein:
the non-conductive can is bonded to the stator core with an adhesive through an underlayer formed on an outer surface of the non-conductive can; and
the underlayer is formed of non-conductive material having a higher affinity for the adhesive than the non-conductive can.

2. A canned motor according to claim 1 , further comprising an annular reinforcing member provided on an outer side of the stator core in a direction of a rotation center axis line of the rotor, the annular reinforcing member being held in contact with an outer surface of the non-conductive can in a circumferential direction.

3. A canned motor according to claim 2 , wherein the non-conductive can is bonded to the annular reinforcing member with an adhesive.

4. A canned motor according to claim 2 , further comprising a stator frame in which the stator core is housed,
wherein the annular reinforcing member further comprises a first portion perpendicular to the rotation center axis line of the rotor, and a second portion extending from an outer-side end portion of the first portion and being held in contact with an inner surface of the stator frame.

5. A canned motor according to claim 1 , wherein a linear expansion coefficient of the annular reinforcing member is equal to or smaller than a linear expansion coefficient of the stator core.

6. A canned motor according to claim 1 , further comprising a non-conductive member to be engaged with a plurality of teeth projecting toward a center of the stator core, the non-conductive member being provided in spaces between inner-circumferential side end portions of the plurality of teeth in the stator core, the non-conductive member being bonded to the can with an adhesive.

7. A canned motor according to claim 1 , further comprising:
a stator frame formed so as to be longer than the stator core in a direction of a rotation center axis line of the rotor, the stator frame being configured to fix the stator core in a state in which the stator core is fitted into an internal space of the stator frame; and
a resin for filling an enclosed space formed in a region between the stator frame and the non-conductive can, the region corresponding to a coil portion projecting from both ends of the stator core in the direction of the rotation center axis line toward an outer side of the stator core.

8. A canned motor according to claim 1 , wherein:
the non-conductive can comprises:
a barrel portion having a hollow shape and extending in a direction of a rotation center axis line of the rotor;
a closing portion for closing an internal space of the barrel portion on a first side in the direction of the rotation center axis line; and
an opening portion for forming an opening of the barrel portion on a second side opposite to the first side; and

the closing portion comprises a portion having an inner diameter decreasing from the second side toward the first side.

9. A canned motor according to claim 1 , wherein the closing portion has a dome shape of which a central portion expands from the second side toward the first side.

10. A canned motor according to claim 1 , further comprising a rib formed on at least one of a surface of the closing portion on the first side and a surface of the closing portion on the second side.

11. A canned motor to be coupled to a vacuum pump and used as a rotary driving source for the vacuum pump, the canned motor comprising:
a stator core;
a rotor provided on an inner side of the stator core; and
a non-conductive can provided between the stator core and the rotor, the non-conductive can being integrated with the stator core and being configured to separate the stator core and the rotor from each other, the non-conductive can being made of resin, ceramic, or composite material thereof,
wherein the non-conductive can is bonded to the stator core with an adhesive,
the canned motor further comprises an annular reinforcing member provided on an outer side of the stator core in a direction of a rotation center axis line of the rotor, the annular reinforcing member being held in contact with an outer surface of the non-conductive can in a circumferential direction, and
the non-conductive can is bonded to the annular reinforcing member with an adhesive through an underlayer formed on the outer surface of the non-conductive can; and
the underlayer is formed of non-conductive material having a higher affinity for the adhesive than the can.

12. A canned motor according to claim 11 , wherein a linear expansion coefficient of the annular reinforcing member is equal to or smaller than a linear expansion coefficient of the stator core.

13. A canned motor according to claim 11 , further comprising a non-conductive member to be engaged with a plurality of teeth projecting toward a center of the stator core, the non-conductive member being provided in spaces between inner-circumferential side end portions of the plurality of teeth in the stator core, the non-conductive member being bonded to the can with an adhesive.

14. A canned motor according to claim 11 , further comprising:
a stator frame formed so as to be longer than the stator core in a direction of a rotation center axis line of the rotor, the stator frame being configured to fix the stator core in a state in which the stator core is fitted into an internal space of the stator frame; and
a resin for filling an enclosed space formed in a region between the stator frame and the non-conductive can, the region corresponding to a coil portion projecting from both ends of the stator core in the direction of the rotation center axis line toward an outer side of the stator core.

15. A canned motor according to claim 11 , wherein:
the non-conductive can comprises:
a barrel portion having a hollow shape and extending in a direction of a rotation center axis line of the rotor;
a closing portion for closing an internal space of the barrel portion on a first side in the direction of the rotation center axis line; and
an opening portion for forming an opening of the barrel portion on a second side opposite to the first side; and

the closing portion comprises a portion having an inner diameter decreasing from the second side toward the first side.

16. A canned motor according to claim 15 , wherein the closing portion has a dome shape of which a central portion expands from the second side toward the first side.

17. A canned motor according to claim 15 , further comprising a rib formed on at least one of a surface of the closing portion on the first side and a surface of the closing portion on the second side.

18. A canned motor according to claim 11 , wherein an end portion of the annular reinforcing member is held in contact with the stator core.

19. A canned motor according to claim 11 , further comprising a stator frame in which the stator core is housed,
wherein the annular reinforcing member further comprises a first portion perpendicular to the rotation center axis line of the rotor, and a se

Assignees

• Ebara Corp

Inventors

• Hozumi Takashi
• Yoshida Naoya
• Ojima Yoshinori
• Inada Takanori
• Nakazawa Toshiharu
• Oyama Atsushi

Classifications

• F04D19/04

  specially adapted to the production of a high vacuum, e.g. molecular pumps · CPC title

• F04D29/60

  Mounting; Assembling; Disassembling {(F04D13/10 takes precedence)} · CPC title

• H02K5/128 Primary

  using air-gap sleeves or air-gap discs · CPC title

• H02K3/18

  Windings for salient poles · CPC title

• F04D17/08

  Centrifugal pumps · CPC title