Machine for driving a lift

Abstract

An electrical machine for driving a pulley, including: a shaft whereon the pulley is mounted; a motor for driving the shaft; at least one brake; a first front bearing for supporting the motor, the first front bearing being arranged on one side of the pulley, carrying a front ball bearing and being supported by at least one damping element; and a second front bearing arranged on the opposite side, carrying at least one ball bearing and supported by at least one damping element. The machine does not contain a rigid connection between the first front bearing for supporting the motor and the second front bearing.

Claims

1. Electrical machinery for driving a pulley, including: a shaft on which the pulley is mounted, a motor for driving the shaft, one or more brakes, a first front bearing supporting the motor, disposed on one side of the pulley, between the pulley and the motor, the first front bearing carrying a front rolling bearing and supported by one or more damper elements, and a second front bearing, disposed on an opposite side of the pulley, carrying at least one rolling bearing and supported by one or more damper elements, wherein there is no rigid connection between the first front bearing supporting the motor, and the second front bearing.

2. Machinery according to claim 1, wherein the motor includes a rear bearing carrying a rear rolling bearing.

3. Machinery according to claim 2, wherein the one or more brakes is supported by the rear bearing.

4. Machinery according to claim 1, wherein the one or more brakes is supported by the second front bearing.

5. Machinery according to claim 1, wherein all the brakes are disposed on the same side of the second front bearing.

6. Machinery according to claim 1, including a plurality of brakes.

7. Machinery according to claim 1, wherein the second front bearing carries a rolling bearing of a two-row type.

8. Machinery according to claim 1, wherein the second front bearing carries a rolling bearing of a single-row type.

9. Machinery according to claim 1, wherein the second front bearing carries two separate rolling bearings.

10. Machinery according to claim 1, including a balance disposed so as to measure a displacement of the machinery induced by a load weighing down the damper element or elements.

11. Machinery according to claim 1, having no casing around the pulley.

12. Machinery according to claim 1, wherein the first front bearing supports the motor and the second front bearing rests on a common base.

13. Machinery according to claim 1, wherein the one or more damper elements is constituted by studs including an elastomer block.

14. Method of driving a lift, using the machinery according to claim 1, wherein the pulley drives cables or a belt connected to a lift car.

Description

(1) The invention will be better understood on reading the following description of one nonlimiting embodiment thereof and examining the appended drawings, in which:

(2) FIGS. 1 and 2 represent known machinery, respectively with an exterior pulley and a rigid central casing,

(3) FIG. 3 represents in perspective an example of machinery constructed in accordance with the invention,

(4) FIG. 4 is a diagrammatic longitudinal section of the machinery from FIG. 3,

(5) FIG. 5 is a front view in the direction of the arrow V in FIG. 3,

(6) FIG. 6 represents a damper stud on its own, in axial section,

(7) FIGS. 7 and 8 are views analogous to FIG. 4 of variants,

(8) FIG. 9 represents a construction detail of a variant damper element, and

(9) FIGS. 10 and 11 are views analogous to FIG. 4 of variants.

(10) The machinery 1 in accordance with the invention represented in FIGS. 3 to 5 includes a pulley 3 mounted on a shaft 5 turning about a rotation axis X that is preferably horizontal.

(11) The pulley 3 may be mounted on the shaft 5 by any appropriate known means, for example by shrinking, conical taper fit or splines and abutment.

(12) The machinery 1 includes on one side of the pulley 3 a motor 7 including a first front bearing 10 supporting the motor 7 and a rear bearing 13 carrying respective front and rear rolling bearings 15 and 17, for example ball bearings.

(13) The motor 7 also includes a rotor 19 and a stator 21, which is carried out by a casing 23 extending between the first front bearing 10 and the rear bearing 13.

(14) The casing 23 and the rear bearing 13 may be made in one piece, as shown, or in the form of parts to be assembled, as shown in FIG. 8.

(15) The rotor 19 may be of the permanent magnet type, notably with ferrite or rare earth magnets. The rotor may be of the flux concentration type or of the type with surface-mounted magnets. The stator may be of the distributed or concentrated winding type. The motor preferably has a three-phase winding.

(16) The motor may drive a fan that is not represented in the drawings or be cooled by a fan driven independently of the rotation of the shaft.

(17) The front bearing 10 is mounted on a base or common base 2 via damper elements 31.

(18) The damper elements 31 are for example studs such as that represented in FIG. 6, including an elastomer block, for example made of rubber, to which are fixed two metal washers carrying a nut or a threaded stud.

(19) Damper studs that may be suitable are commercially available from the company PAULSTRA under the trademark RADIALFLEX and allow working of the elastomer in axial compression and/or in radial shear.

(20) The base may be produced with an opening for passing through cables or the belt, shown generically as 4, connected to the lift car. Bolts and/or nuts that are not represented may be used for fixing the first front bearing 10 to the base, these bolts being fixed to the damper studs 31, which thus support the weight of the motor.

(21) The machinery 1 includes, on the side opposite the motor, a second front bearing 35 supporting one or optionally more brakes 40.

(22) Each brake 40, of the axial type known in itself, includes a yoke 41 housing an electromagnet that is not represented in the drawings for moving when energized an armature 42 carrying a brake lining. The armature is loaded by springs to bear against a disk 43 turning with the shaft 5.

(23) The brake or brakes 40 are for example of the lack of current type, i.e. they lock rotation of the shaft when not energized.

(24) The second front bearing 35 carries a rolling bearing 51 and rests on the base via damper elements 32.

(25) A second rolling bearing 53 may be carried by a bearing 85 that may be made in one piece with a protective casing 86 of the brake or brakes 40.

(26) The damper elements 32 are preferably identical to the damper studs 31, as shown here.

(27) The machinery is advantageously equipped with a balance 34 for determining the torque exerted on the pulley when the motor is stopped. This can make it possible to start the motor without jerking, as indicated above.

(28) The balance 34 is an inductive sensor, for example, preferably of the proportional output type, fixed to the base of the bearing 10 near the edge farthest away from the median longitudinal plane M. This sensor may measure its distance from the support base, which is representative of the state of deformation of the damper element or elements 31 and 32.

(29) In the variant shown in FIG. 7, the machinery 1 includes two brakes 40.

(30) In the FIG. 8 variant, the rear bearing 13 is attached to the casing 29. The second front bearing 35 supporting the brake or brakes is adapted to receive a two-row rolling bearing 51.

(31) In the variant shown in FIG. 10, the second front bearing 35 includes two separate rolling bearings 511 and 512.

(32) In a variant that is not shown, the machinery includes only one bearing on the motor side, namely the first front bearing 10, in which case the rolling bearing 15 can be of the two-row type, or the first bearing may include two separate rolling bearings.

(33) In the variant shown in FIG. 11, the brake or, optionally, brakes are supported by the rear bearing 13.

(34) The second front bearing 32 includes a single-row rolling bearing 51.

(35) There is shown in FIG. 9 a variant damper element, for example for the first front bearing 10 as shown, it being understood that this also applies to the second bearing 35.

(36) The damper element includes two elastomer shoes 31a and 31b. The first 31a is disposed between the bearing 10 and the base S receiving the machinery. The second 31b is disposed between the base S and a washer 101 retained by a screw 102 screwed into the bearing 10. The shoe 31a may take the form of a soleplate in contact with the whole of the lower face of the bearing 10. The shoe 31b may be staggered, in order to be centred in the hole in the base S for the screw 102 to pass through.

(37) Of course, numerous modifications may be made to the examples shown without departing from the scope of the present invention.

(38) For example, the number and the nature of the brakes may be modified. Calliper brakes may be used, for example, instead of disk brakes.

(39) The casing of the motor may be produced, for example machined or cast, in one piece with one and/or the other of the bearings.