AU762273B2 - A lift - Google Patents

Description

A LIFT Technical Field The present invention relates to lifts and more particularly but not exclusively to lifts for domestic use.

Background of the Invention Most lifts are generally complex and expensive and particularly designed for high rise buildings. There complexity and cost is therefore prohibited from a domestic point of view.

As an alternative to lifts, in domestic circumstances frequently inclinators are used. However inclinators are relatively noisy and occupy considerable space.

Object of the Invention It is the object of the present invention to overcome or substantially ameliorate at least one of the above disadvantages.

Summary of the Invention There is disclosed herein a lift including: a guide assembly which is to extend between an upper level and a lower level; a lift carriage mounted in the guide assembly so as to be guided thereby in its movement between the upper level and the lower level; drive means to move the carriage between the upper and lower levels, said drive S 20 means including; a power screw extending generally parallel to the direction of movement of the carriage, and passing through the carriage; S•a motor coupled to the power screw and operable to rotatably drive the power screw about its longitudinal axis; [R\LIBIT]02866.doc:tyb:KEH a nut attached to said carriage and engaged with said power screw so that rotation of said power screw causes movement of the said nut and therefore said carriage between the two levels, and wherein, said lift further includes means manually operable to engage the power screw to cause rotation thereof.

Brief Description of the Drawings A preferred form of the present invention will now be described by way of example with reference to the accompanying drawings wherein: Figure 1 is a schematic side elevation of a lift; and Figure 2 is a schematic top plan view of a device to aid manual operation of the lift of Figure 1.

Detailed Description of the Preferred Embodiments In the accompanying drawing there is schematically depicted a lift 10 to move people between an upper level 11 and a lower level 12. In this embodiment the levels 11 and 12 are on opposite sides of the lift 10 however it should be appreciated the levels 11 and 12 could be on the same side of the lift.

The lift 10 includes a guide assembly 13 including four vertically extending guide members 14 which engage and guide a lift carriage 15. The carriage 15 is moved between the levels 11 and 12.

The lift carriage 15 adjacent the lower four corners thereof is provided with spring loaded guide bars 16 which engage the members 14 to guide the carriage 15 in its vertical movement.

Supported on the assembly 13 is a motor and gear box assembly 17 which drives a vertically extending power screw 18. The power screw 18 is generally parallel and 25 coextensive with respect to the guide assembly 13 and is generally centrally mounted Sthereof. The power screw 18 passes through the carriage 15 and threadably engages a nut 19. The nut 19 is attached to the floor 20 of the carriage 15 so that movement of the nut [R:\LIBTT]02866.doc:tyb:KEH 19 causes movement of the carriage 15. By being attached to the floor 20 the nut 19 is prevented from rotational movement.

Surrounding the screw 18 internally of the carriage 15 is a protective sleeve 21.

The screw 18 passes through an aperture 22 in the roof 23 of the carriage 15. To aid in minimising vibration, a rubber bush is mounted in the roof 23 and slidably engage the screw 18. The screw 18 is suspended from a top member 24 and terminates above a bottom member 26.

Typically external lift doors would be provided at each level 11 and 12 and would be operated by means of a control system so that they remained closed unless the carriage 15 was aligned therewith. Still further, the carriage 15 would be provided with its own doors and again a control mechanism would be provided to ensure that they remain closed unless the carriage 15 was located at one of the levels 11 and 12.

In Figure 2 there is schematically depicted a device 25 to aid in manually lowering the carriage 15. The device 25 would be used should there be a power failure or failure of the motor and gearbox assembly 17.

The device 25 includes a collar 26 that surrounds the power screw 18. The collar 26 would normally only slidably engage the power screw 18 during normal operation.

However, if there is a power failure the collar 26 is moved into engagement with the power screw 18 so as to be clamped thereto. In particular, the collar 26 is split and has extending from the two extremities 27 a pair of flanges 28. The flanges 28 are spaced by a gap 29, which when diminished moves the collar 26 into a position at which it is clamped to the power screw 18.

Mounted on the extremity of the flanges 28 is a bracket 30 having a shaft 31 extending through the flanges 28. Mounted on the bracket 30 is a handle 32 by means of a pivot pin 33. The handle 32 has a flat portion 34 and an arcuate portion 35. When the arcuate portion 35 is engaged with the shaft 31 the collar 26 is clamped to the power screw 18. When the handle 32 is pivoted in the direction of the arrow 36 the flat portion .*34 is positioned adjacent the shaft 31. When in this configuration, the collar 26 is released from clamping engagement with the power screw 18.

[R:\LIBTT]02866doc:tyb:KEH In respect of the above device 25 it should be appreciated that the protective sleeve 21 is rotatable about the longitudinal axis of the power screw 18 and is provided with an aperture 37 through which the flanges 28 pass.

Should there be a power failure, a user of the device 25 rotates the handle 32 so as to position the arcuate portion 35 in engagement with the shaft 31. The collar 26 is then clamped into engagement with the power screw 18. Rotation of the device 25 in the direction of the arrow 38 will then cause rotation of the power screw 18 and lowering of the carriage 15. The power screw 18 can be released by moving the handle 32 in the direction of the arrow 36.

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Claims (7)

1. A lift including: a guide assembly which is to extend between an upper level and a lower level; a lift carriage mounted in the guide assembly so as to be guided thereby in its movement between the upper level and the lower level; drive means to move the carriage between the upper and lower levels, said drive means including; a power screw extending generally parallel to the direction of movement of the carriage, and passing through the carriage; a motor coupled to the power screw and operable to rotatably drive the power screw about its longitudinal axis; a nut attached to said carriage and engaged with said power screw so that rotation of said power screw causes movement of the said nut and therefore said carriage between the two levels, and wherein, 15 said lift further includes means manually operable to engage the power screw to cause rotation thereof

2. The lift of claim 1 wherein said carriage includes a floor to which said nut is attached generally centrally of the floor.

3. The lift of claim 1 or 2 further including a sleeve mounted in said carriage and surrounding said power screw.

4. The lift of claim 3 wherein said sleeve has an aperture, and said manually operable means extends through said aperture.

The lift of claim 4 wherein said manually operable means includes a collar to be brought into clamping engagement with said power screw, and a handle S 25 extending therefrom. [R:\LIBTT]02866.doc:tyb:KEH

6. The lift of claim 5 wherein said handle is operable to move said collar into clamping engagement with said power screw, with said handle being adaptively engaged by a user to cause rotation of the power screw.

7. A lift substantially as hereinbefore described with reference to the accompanying drawings. Dated 16 April, 2003 Norman Tonkin Patent Attorneys for the Applicant/Nominated Person SPRUSON FERGUSON 0* Ce *e oo [R:\LIBTr]02866.doc:tyb:KEH