AU2008101113A4 - Hoist system - Google Patents

Description

Regulation 3.2

AUSTRALIA

Patents Act 1990 INNOVATION PATENT SPECIFICATION

(ORIGINAL)

Name of Applicants: Actual Inventor: Address for Service: William Mark Lindqvist Deborah Ruth Lindqvist Roland John Lindqvist Lavinia Lindqvist Roland John Lindqvist DAVIES COLLISON CAVE, Patent Attorneys, 1 Nicholson Street, Melbourne 3000, Victoria, Australia Innovation Patent specification for the invention entitled: "Hoist system" The following statement is a full description of this invention, including the best method of performing it known to us: Q \OPER\RSH\JUNE 08 DEC 08\30683454-316.DOC 14/11/08 P:FOPER ~S 0683454-INNOVoc-I4/I 12038 00 -1- 0 HOIST SYSTEM The present invention relates to a hoist system for lifting a disabled or elderly patient and more particularly to a hoist system in which the hoist is suspended from an overhead track.

Patient lifting systems comprising a lifting hoist suspended from an overhead track are 00 known. The track itself is fixed to, or suspended from, the ceiling or may be part of a portable overhead gantry. The hoist is connected to a shackle or shackle plate of a runner movable along the track to enable a patient held in a sling beneath the hoist to be moved from one location to another. The connection between the hoist and runner is a releasable connection as the hoist is conventionally in the form of a portable unit which can be used in different locations as required. Conventionally the hoist unit is attached to the runner by means of a hook at the upper end of a hoisting strap of the hoist unit. To facilitate engagement and removal of the hook when the track is at a height beyond the reach of a person standing on the ground, the hook may be associated with an extension handle, sometimes referred to as an "arm reacher" to enable manipulation of the hook from the ground.

The present invention provides a hook assembly with a safety latch which ensures that its hook cannot be dislodged from the runner, the latch being controlled by the action of an extension handle by which the hook is manipulated and which is removable when the hook has been engaged with the runner so that it does not impede access to the hoist system.

The present invention further provides a hook assembly for attachment of a patient lifting hoist to an overhead track, the hook assembly comprising a body having means for attachment to the hoist, a hook for attachment to a runner of the overhead track, a latch associated with the hook for retaining the hook in engagement with the runner, and a mounting for releasable retention of an extension handle for manipulation of the hook when engaging and disengaging from the runner, the mounting being associated with means to effect remote release of the latch by means of the handle when retained.

P OPERRSH 30683434-INNOVdo-1411/20i)8 00 -2z The present invention still further provides a hook assembly for attachment of a patient lifting hoist to a runner of an overhead track, the hook assembly having a hook for engagement with the runner, and an extension handle for manipulating the hook from Cc below for engagement and disengagement with the runner, the handle being releasably retained by magnetic retention means to permit removal of the handle for storage when the lifting hoist is in use.

00 An embodiment of the invention will now be described by way of example only with reference to the accompanying representations in which: Figure 1 shows the upper end part of a hook assembly in accordance with the preferred embodiment, the assembly being shown in a condition prior to its engagement with an overhead runner, with a latch arm of the assembly being shown in a released position; Figure 2 is a view similar to Figure 1 but showing the hook when engaged with the overhead runner, with the latch arm in its latching position; Figure 3 is a view of the overall assembly in the condition shown in Figure 2; Figure 4 shows schematically the operative structure of the hook assembly, with the latch arm shown in its latching position; and Figure 5 is a schematic view similar to Figure 4 but showing the upper end portion of the extension handle engaged into a sleeve of the hook assembly with the latch arm being displaced to its released position.

The hook assembly shown in the accompanying drawings is designed for use with a hoist unit (not shown) which carries a patient sling. The hoist unit, which is well known per se, includes a motor-driven strap cassette for a hoist strap 2 which extends upwardly from the cassette. The upper end of the strap 2 is attached to a swivel coupling 4 carried by the body 6 of the hook assembly. In the preferred embodiment, the body 6 of the hook assembly is formed by a pair of spaced parallel plates, with the swivel coupling 4 being connected to the body by being bolted between the plates. A hook 8 engageable with a shackle plate 10 of an overhead runner is fixedly mounted between the two plates. The hook 8 is associated with a spring-biased latch arm 12 pivotally mounted between the PXOPERXRSH30683454-INNOVdoc-I411 MO)S 00 -3- 0 z plates for pivotal movement between a released position shown in Figure 1 in which the hook 8 is able to be engaged over the shackle plate 10, and a latching position shown in Figures 2 and 3 to prevent accidental release of the engaged hook 8 from the shackle plate Cc 10. The spring bias applied to the latch arm 12 acts in a sense to move it to its latching position.

00 The body 6 of the hook assembly also carries a tubular housing or sleeve 14 which extends vertically and is open at its lower end to releasably receive an extension handle 16 to enable manipulation of the hook 8 from the ground for engagement/disengagement relative to the shackle plate 10. It will be seen that the lower end of the sleeve 14 is flared outwardly to facilitate location of the upper end of the handle 16 into the sleeve 14.

As will now be described with reference to the schematic representations of Figures 4 and mounted within the sleeve 14 is an actuator in the form of a piston 18 to which the upper end of the handle 16 is releasably coupled and which co-operates with the latch arm 12 to displace the latch arm to its released position (see Figure 5) in response to upwards force applied by the handle. The piston 18 is composed of a hard wear-resistant plastics and is shaped at its upper end with a head 18a which, in a lower stop position of the piston 18 (see Figure engages a bush 20 mounted to the internal wall of the sleeve 14. The piston 18 is held centred within the sleeve by co-operation between its head 18a and the wall of the sleeve and between its body and the stop bush 20. It will be seen from Figures 4 and that the upper surface of the piston head 18a is engaged by a part of the spring-loaded latch arm 12 and the lower stop position of the piston 18 corresponds to the latching position of the latch arm. Movement of the piston 18 upwardly from that position by upwards movement of the handle 16 causes the latch arm to be displaced into its released position against the action of its biasing spring which is indicated at 24 in Figures 4 and A permanent magnet 26, a rare earth magnet for example, is incorporated within the lower part of the piston 18 and is exposed to the lower face of the piston via a short cylindrical passage. The upper end portion of the handle 16 is formed with a sleeve 28, also of a wear-resistant plastics, which is a sliding fit within the interior of the sleeve 14. The P: OPERRSHUf30683454-INNOV.dc-14/1 I /2n)8 00 -4z sleeve 28 carries at its upper end a projecting metal tip 30 of a length and diameter to magnetically engage the lower face of the permanent magnet 26 in the piston 18 by access through the short cylindrical passage at the lower end of the piston. Accordingly, Cc engagement of the upper end portion of the handle into the sleeve 14 will result in releasable magnetic engagement between the handle 16 and piston 18 and this engagement will be assured as the plastic sleeve 28 acts to centre the upper end of the handle 16 within 00 the sleeve 14, and the piston 18 itself will be centred within the sleeve 14 by its cooperation with the internal surface of the sleeve 14 and the stop bush 20. The magnetic force between the handle 16 and piston 18 will be such that once engaged it will adequately support the weight of the handle 16 to prevent accidental disengagement, yet disengagement can readily be achieved when required by applying a sharp downwards tug to the handle 16.

Although the magnetic retention system just described is preferred as it provides a safe and reliable retention of the handle to the piston in a relatively inexpensive manner, it is to be understood that it is within the broad scope of the invention for other forms of retention system to be used to achieve a similar effect, for example involving the use of spring clip or a simple screw threaded connection.

In practice, the upper end of the hoist strap 2 will be permanently attached to the swivel connection 4. To attach the hoist to the shackle plate 10 of the overhead runner, the upper end of the handle 16 is inserted through the open end of the sleeve 14 into engagement with the piston 18 therein and, using the handle 16, the hook assembly is manipulated so that its hook 8 engages into the shackle plate 10. During this action, the latch arm 12 may be held closed by its spring bias, in which case it will open against its spring bias upon engagement with the shackle plate as the hook itself is moved over the shackle plate and then automatically release back in order to latch the hook, or alternatively it may be held open against its spring bias by upwards pressure applied by the handle 16 to the piston 18 and when the hook is engaged release of upwards pressure on the handle will enable the latch arm 12 to move to its latching position. After engagement and latching of the hook the handle can then be pulled downwardly with sufficient force to disengage it from its P OPERkRSHU 61454 NNOV.do-14I11/200 z coupling with the piston. The handle can thus be removed from the hook assembly and stored in a convenient place, for example in the floor storage trolley usually provided with hoist systems of this type. When stored, the handle will not impede access of the operator to the patient.

In order to remove the hook assembly and thus the hoist from the overhead runner, the 00 hoist unit is driven downwardly onto the floor storage trolley sufficiently to ensure that some slack remains in the strap. The operator then holds the strap taut with one hand and with the other hand inserts the upper end of the handle 16 into the sleeve 14 for engagement with the piston 18, and by applying some upwards pressure to the handle the piston 18 is pushed upwardly to move the latch arm 12 to its released position whereby the handle can be manipulated to remove the hook from the shackle plate.

The embodiment has been described by way of example only and modifications are possible within the scope of the invention.

Claims (8)

1. A hook assembly for attachment of a patient lifting hoist to an overhead track, the Cc hook assembly comprising a body having means for attachment to the hoist, a hook for attachment to a runner of the overhead track, a latch associated with the hook for retaining the hook in engagement with the runner, and a mounting for releasable retention of an 00 extension handle for manipulation of the hook when engaging and disengaging from the runner, the mounting being associated with means to effect remote release of the latch by means of the handle when retained.

2. A hook assembly according to claim 1, wherein the mounting comprises a housing into which an upper end of the handle can be inserted from below for engagement with an actuator to which the latch is operatively connected, the latch being spring biased to a latching position and being displaceable to a released position against the spring bias by displacement of the actuator by means of the handle.

3. A hoist system according to claim 2, wherein the actuator is in the form of a piston slidable within the housing whereby upwards displacement of the piston by force applied by the handle displaces the latch to its released position in opposition to the spring bias.

4. A hoist system according to claim 2 or claim 3, wherein the handle is releasably retained to the actuator by magnetic force sufficient to support the weight of the handle.

A hoist hook assembly according to any one of claims 1 to 3, wherein the handle is releasably retained in an operative condition to facilitate manipulation of the hook from below by magnetic force sufficient to support the weight of the handle and prevent its release except by application of deliberate force to do so.

6. A hook assembly for attachment of a patient lifting hoist to a runner of an overhead track, the hook assembly having a hook with a safety latch to prevent dislodgement of the hook from the runner, the latch being controlled by the action of an extension handle by P\OPER\RSI30683454-INNOV doc-14/11 /200 -7- z which the hook is manipulated and which is removable when the hook has been engaged with the runner.

7. A hook assembly for attachment of a patient lifting hoist to a runner of an overhead track, the hook assembly having a hook for engagement with the runner, and an extension handle for manipulating the hook from below for engagement and disengagement with the O0 runner, the handle being releasably retained by magnetic retention means to permit Sremoval of the handle for storage when the lifting hoist is in use.

8. A hook assembly substantially as hereinbefore described with reference to the accompanying drawings.