Tubular induction motor with two directions of rotation for home-automation applications
Tubular induction motor with two directions of rotation contained in a tube of a tubular actuator designed to be installed in a building. The tubular induction motor includes a squirrel cage rotor supported by bearings and a stator including a stack of metal laminations forming a central bore and centered in the tube, wherein a support part of a bearing is centered in the central bore, wherein the bearing is of the plain and conductor type and wherein it is placed as close as possible to a short-circuiting ring of the rotor, preferably less than 2 mm, and preferably less than 1 mm away.
1. Tubular induction motor ( 20 ; 30 ) with two directions of rotation, contained in a tube ( 11 ) of a tubular actuator designed to be installed horizontally in a building and adapted for maneuvering a mobile home-automation element, comprising a squirrel cage rotor ( 24 ; 34 ) supported by bearings ( 26 ; 36 ; 46 ) and a stator ( 12 ) comprising a stack of metal laminations forming a central bore ( 12 a ) and centered in the tube, wherein support parts of the bearings ( 29 ; 37 ; 47 ) are centered in the central bore, wherein the bearings are of the plain and conductor type and wherein they are each placed less than 2 mm away from short-circuiting rings ( 24 c ) of the rotor.
2. Motor according to claim 1 , wherein the support parts comprise bearing surfaces for centering the bearings ( 29 c ; 37 g ; 47 g ) and bearing surfaces for centering in the central bore ( 29 b ; 37 j ).
3. Motor according to claim 2 , wherein the bearing surfaces for centering in the central bore comprises shoulders and/or wherein the central bore comprises a shouldered bearing surface.
4. Motor according to claim 1 , wherein the support parts are sleeves ( 29 ) having the sole function of centering the bearings relative to the central bores, the sleeves being locked by a casing ( 27 ) covering end winding ( 13 ) of the stator.
5. Motor according to claim 1 , wherein the support parts are casings ( 37 ; 47 ) covering end winding ( 13 ) of the stator, the casings comprising a tubular extension ( 37 e ; 47 e ) of an inner web ( 37 c , 47 c ).
6. Motor according to claim 5 , wherein the inner web ( 47 c ) is connected to the rest of the casing via an articulation ( 37 h , 47 h , 47 i ).
7. Motor according to claim 4 , wherein a distance from the center of the bearing to the stator is less than the distance from the center of the bearing to a radial web ( 27 d ; 37 d ; 47 d ) of the casing.
8. Motor according to claim 1 , wherein the rotor comprises a stack of metal laminations, wherein each end of the stack of metal laminations of the rotor includes a portion ( 24 d ; 34 d ) of reduced diameter.
9. Motor according to claim 1 , wherein the radius (R 4 ) of a portion of bearing facing the rotor is at least greater than the radius (R 1 , R 2 , R 3 ) of a short-circuiting ring of the rotor.
10. Motor according to claim 1 , wherein a universal joint ( 50 ) is place on a shaft of the rotor, the bearing ( 36 ) being placed between the rotor and the universal joint, and wherein there is a first clearance (Z 3 ) between the rotor and the bearing and a second clearance (Z 4 ) between the universal joint and the bearing, the first clearance being less than 2 mm and the second clearance being less than 2 mm.
11. Motor according to claim 1 , wherein the length of the stack of metal laminations forming the stator is greater than the length of the stack of metal laminations forming the rotor.