Elevator reluctance linear motor drive system

• US 6,305,501 B1
• Filed: 03/14/2000
• Issued: 10/23/2001
• Est. Priority Date: 06/19/1997
• Status: Expired due to Fees

• Current Assignee: Kone Corporation
• Original Assignee: Kone Corporation
• Inventors: Kallioniemi, Antti, Kähkipuro, Matti, Pelto-Huikko, Raimo
• Primary Examiner(s): Salata, Jonathan
• Application Number:
  US09/446,063
• Time in Patent Office: 588 Days
• Field of Search: 187/289, 187/250, 187/251, 187/409, 318/135, 318/701, 310/12-14, 104/290, 104/292, 104/293
• US Class Current: 187/289
• CPC Class Codes: B66B 11/0407 actuated by an electrical linear motor in the counterweight B66B17/12
• CPC Class Codes: H02K 41/03 Synchronous motors; Motors moving step by step; Reluctance motors H02K41/035 takes precedence
• CPC Class Codes: H02K 7/08 Structural association with bearings

Abstract

A drive system for an elevator includes a drive machine by means of which the for moving and supporting an elevator car. The primary circuit of a linear motor is permanently fitted to a wall of a building while its secondary circuit is fitted in conjunction with the elevator car and moves with the elevator car. Pressurized air is supplied between the primary and secondary circuits of the reluctance-type linear motor to maintain an air gap between them.

Claims

1. An elevator comprising an elevator car and a drive machine, the drive machine comprising:

a linear motor primary circuit permanently fitted to a wall;

a linear motor secondary circuit fitted in conjunction with the elevator car and moving together with the elevator car, the elevator car being movable and supportable by the drive machine,

the primary and secondary circuits of the linear motor comprise teeth placed successively in a direction of motion of the elevator, slots being provided between successive teeth and windings of the linear motor being fitted in the slots in both the primary and secondary circuits, magnetic flux induced by the windings completing its loop substantially through two adjacent teeth and a yoke part being provided between the teeth in the primary circuit and in the secondary circuit.

2. The elevator as defined in claim 1, further comprising pneumatic equipment for supplying pressurized air into a space between the primary circuit and the secondary circuit of the linear motor, an air gap between the primary circuit and the secondary circuit being regulatable by the pressurized air.

3. The elevator as defined in claim 1, further comprising a track for the elevator and control devices for supplying required power to the windings of the linear motor, the control devices for the primary circuit being distributed along a length of the track of the elevator with each winding being controlled separately.

4. The elevator as defined in claim 2, wherein the pneumatic equipment comprises a pneumatic pressure source and a pipe system with a nozzle, said nozzle being fitted in the air gap between the primary and secondary circuits of the linear motor.

5. The elevator as defined in claim 4, wherein the linear motor and the pneumatic equipment are disposed on two or more sides of the elevator car.

6. The elevator as defined in claim 2, wherein the linear motor and the pneumatic equipment are disposed on two or more sides of the elevator car.

7. The elevator as defined in claim 1, wherein the linear motor is disposed on two or more sides of the elevator car.

8. The elevator as defined in claim 1, wherein tooth pitch of the primary circuit and tooth pitch of the secondary circuit are implemented in accordance with the vernier principle.

9. The elevator as defined in claim 1, wherein at least one of the primary circuit and the secondary circuit are coated with a plastic film on a surface facing the air gap.

10. The elevator as defined in claim 1, wherein the wall in which the primary circuit of the linear motor is permanently fitted is a substantially vertical wall.

11. The elevator as defined in claim 1, wherein the secondary circuit of the linear motor is the only circuit on the elevator car in order to minimize weight of the elevator car.

12. The elevator as defined in claim 11, wherein the primary circuit of the linear motor is the only circuit on the wall.