CA2167852A1 - Patient lift modification - Google Patents

Abstract

This invention relates to a patient lifting and transfer apparatus for transport of a physically disadvantaged person from bed to bedside chair or commode.

Description

~-- 2167852 FIELD:
m is invention relates to a patient lifting and transfer apparatus for transport of a physically disadvantaged person from bed to bedside chair or commode.

BA~K~K~u~D:
There is currently a need to enable elderly citizens to remain as long as possible in their own home, rather than be institutionalized. This is cost effective and beneficial to the citizens concerned.

To meet the above requires the lift in question to be re~n~hly priced, easily installed, free standing, patient operable without assistance and no modification to building st~ uLes to facilitate installation. This unit should offer no obstruction at the floor level around the bed and provide a greater measure of indepPndPnce of mobility to the patient.

STATE OF THE ART:

Many patents have been issued for lifting and transport devices that only partially meet the above requirements~
Ref. U.S.Patent #4571758 - Samuelson Feb/86 Ref. U.S.Patent #5077844 - Twitchell Feb/86 I would draw your attention to the base mounting system in both cases. These units require permanent fastening (bolting) to the wall and/or floor.

This method pL~su~poses that structural members, of sufficient mass,strength and rigidity, are present beneath the floor or behind the wall facings, to afford the structural integrity required to support the flanges under a significant load of changing vector and magnitude.

`- 21 67852 Detailed inspection and/or structural modifications to the area in question would be required if these units were installed in already existing domestic or institutional facilities, which would incure a significant cost and be i~,.ol,v~nient, undesireable and l~n~creptable for "in home use".

The above noted patents do not meet the requirements stated in paragraphs 1 and 2 of Ba~yro~ld.
Ref.Canadian Patent #1170604 - Cote July/84 This unit is designed to be operated by a single person who is physically disabled - see Object, para 10.

Para 30 and Fig.2-22 indicate the t~d-,~v~Lse legs must be extended to stabilize the unit. This will be mandatory to ensure stability under load when patient is over the bedside chair.

This stabilizing operation cannot be performed by the physically disabled patient who is confined to bed or wheelchair.

This patent leaves unsatisfied the requirement for a transfer lift operable by the patient alone with no assistance.
Ref.U.S.Pat. # 4070721 - Stasko Feb/66 Ref.U.S.Pat. # 3234568 - Fischer Jan/78 Both disclosures noted above must involve a second party to assist in the transport of the patient and require considerable space around the bed in order to manoeuvre the unit.

The features needed, as stated in BaukyLu~ld~ are still unsatisfied by this patent.

` 21 67852 Ref.U.S.Pat. #2809381 - Colander Oct/57 I would draw your attention to the limitations of location of the lift unit relative to the bed: -Specifically - the lift, as an integral part of the bed alone and in a fixed position relative to this bed alone, restricts the ability of the unit to deliver a patient to one side only of the bed. This design will result in additional cost in manufacture, i.e. bed plus lift and the unit would not be acceptable to any bed in question.

The requirements as stated in Ba~yro~ld, para 2 and 3, are still unsatisfied by this patent.

OBJECT OF INVENTION:

By the novel combination of: Base and stLu~tuLe design.
Drive and control system arrangement.
to provide an improved transfer lift for "in home~ use or institutional use which will transfer a physically disabled person from bed to wheelchair or commode and back to bed and meet specifications as follows:

1. Simple and convenient to operate without assistance by a paraplegic or similarly disabled person.

2. Free st~n~;ng, not attached to bed or building stL~ Le, to assure ease of installation at a minimum cost.

3. Capable of patient delivery to either side of the bed and to be compatible with any bed arrangement and operate efficiently in a restricted area, with side of bed against a wall.

4. Provide a base design offering no obstruction to pedestrian or wheelchair ~ v~..~nt around the bed.

5. Provide a structure that is simple and economical to manufacture, convenient to install and easily relocated or r~..~v~d.

6. Provide an enclosed lift mechanism which is standard, reliable, econ~;cal, readily available and simple to service or replace.

7. Provide a control, readily available to patient, at all times, which affords simple operation by a-physically disabled person, having restricted hand movement.

8. Is visually acceptable and compatible with bedroom decor.

SU~RY:

A rigid, free st~n~;ng lifting device consisting of a rigid base, verticle column and an overarm, extending radially outward from the top of the column.
The overarm is free to rotate 180 degrees about the vertical axis of the column.

BASE:

Commensurate with this invention, the lift consists of a novel base design comprised of a horizontal "T" shaped base, lying flat on the floor, all three tubular members of which are removeable and interchangeable on assembly.

The long arm of the "T" to be located longitudinally under the bed and the short arms of said "T" to be located against and parallel to the wall at the head of the bed. This base ensures an obstruction-free floor area around the bed and a stable unit under all conditions without adjustment.

ALTERNATE BASE:

An alternate base structure, having either one of said short legs replaced by a leg having its members geometrically ~s~mbled in a "Y" pattern. This allows positioning of alternate base under the bed and permits either side of the bed to be located against the wall, allowing normal operation within a confined space.

VERTICLE COLUMN:

A cylindrical member is attached latterally to the ~T~ at the junction of the arms, having the long axis of the cylinder positioned vertically and forms the lower fixed section of said vertical column.

A square tubular member, forming the upper rotating section of said column, is contained within the cylinder and extends vertically above said cylinder which terminates in an arm PxtPn~ing laterally outward fastened to the upper end of the tubular member.

This unit forms the overarm assembly which, supported by radial bearings, is free to rotate through 180 degrees within the vertical cylinder.

LIFT DEVICE:

A motorized lifting unit contained within the tubular member, PxtPn~ and retracts a cable running along the overarm to a pulley at extreme outer end of the arm.

This unit is positioned with the cylinder behind the head of the bed so as to allow the overarm to swing freely through 180 degrees over both the bed and also the bedside chair or commode.

To support a disabled or infirm person, a spreader bar, complete with lifting Straps hanging from either end is attached to the cable. Said straps terminate with hooks which provide a simple att~ t to the cradle.

OPERATION:

Control and placement of the lift overarm by a disabled person on the bed is provided by a lanyard fastened to the overarm and cont~in;ng the control switch which hangs within easy reach of the patient at all times.

Said lanyard is used by the patient on the bed, to swing the overanm over the bed, which enables said patient to hook the cradle, on which he is now sitting, to the support straps hanging from the spreader bar.

Lifting can proceed on command from the patient and when clear of the bed, movement to the bedside chair position is affected by a slight push against f - the bedside. This will permit the overarm and patient to swing freely over a correctly placed chair or commode, located beside the bed, lowering can now proceed on command by the patient.

~ - 21 67852 ~Cl~lCATIONS:

n~r~RTpTIoN OF DRAWINGS:
Fig.l. Is an isometric view of the lift.
Fig.2. Is detail of cable attachment to actuator.
Fig.3. Is detail of alternate base.

DETAILED DESCRIPTION OF INVENTION:
Reference Fig.1.
1. Base members 1, 2 and 3, rigidly attached to vertical cylinder ~CsPmhly - 7, at points - 4 - 5 - 6, by means of an internal sleeve Fig.3-2. The overarm - Fig.1-9, de~rh~ble at 27, is attached to the square tubing - 8, which is free to rotate within the verticle cylinder -7, supported by radial bearings which allows the overarm - 9, to rotate freely through 180 de~ees with limit stops (not shown) on the cylinder perephery -7, to prevent overtravel of the overarm.

2. A linear actuator - 21, acting as the motor drive unit, is mounted within the square tubular member - 8. The actuator translating tube - 23, contained within the actuator cover tube - 22, is free to extend and retract within the square tube - 8, and is driven by motor Fig.1-21.

Reference Fig.2.
3. Detailing cable actuator attachment - a hardened cross pin - 4, only slightly shorter than the corner to corner dimension of the bore of the tube - 8, ia fastened to the end of the translating tube - 23.

4. Pin - 4, serves as the required anti-rotating unit for the actuator translating tube - 23, also acts as a guide for tube - 23, and ensures the correct positioning of cable -11, during the linear travel of the translator tube - 23, within the tube - 8.

5. The Lift Cable - 11, passes through cross pin - 4, and enters translating tube end. Fastening of cable - 11, (not shown) is by a swaged ball on cable - 11, which will not pass through translator tube cable entry hole.

Referring to Fig.l.

6. The Lift Cable - 11, attached to actuator translating tube -23, travels up through bore of tube - 8, over pulley - 12, within overarm -9. Cable -11, exits over overarm - 9, pully - 10, and is fastened to spreader bar - 13, at point - 14.

7. Lifting straps - 15 and 20, complete with back restraining strap - 19, terminate with hooks - 16 and 18, which are fastened (hooked) to cradle - 17.

8. Cradle - 17, facilitates the secure lift of the patient since the lifting straps - 15 and 20, pass in front of patient's shoulders, preventing falling forward and back restraining strap -19, located behind the patient, ~L~v~n~s patient falling backward.

Referring to Fig.3:

9. The alternate base, which replaces either base leg Fig.l-l, or 1-2, is assembled as shown Fig.3, and is comprised of tubing as in Fig.1-1-2-3.

10. The coupling of this alternate leg to the vertical assembly Fig.1-7, at point 4, is facilitated by an internal sleeve, Fig.3-2, which fits snugly into bore of vertical assembly -Fig.1-7, at points indicated at either Fig.1-4 or Fig.1-5, as required and is secured by a 1/2" dia.bolt (not shown).

11. When installed this alternate leg, due to its orientation, will be contained completely within the area under the bed.

12. Since this leg is inter~h~nge~hle with either leg, Fig.l-l, or Fig.1-2, the bed may now be located against the wall on either left or right side, when required, due to restricted space in area of location.

13. Stability of the lift unit is assured when the alternative leg is installed, since upon rotation of the overarm through 180 deyL æ s, the extended lift cable will scribe an arc at the floor level, beyond which the base bearing points will lie, Fig.1-24-25-26.

14. This ensures the centre of gravity of the lift load is never beyond the bearing points, Fig.3-4-5 and legs, Fig.1-24-25-26.

Claims (2)

1. A. Specifically a base structure for a patient lift, fastened to a verticle column and comprised of 3 arms oriented in the form of a "T", having the long arm of the "T" positioned under the bed and the short arms of said "T" positioned at the head of the bed.

B. An alternate base structure employing a modified short arm which can replace either of the short arms noted in "A" above.

Said alternative short arm comprised of two members oriented respective to one another so a s to form a "Y" pattern.

Bearing points of said modified short arm to fall beyond an arc (scribed by a vertical extension to the floor of the lifting cable, i.e. centre of gravity) as the overarm of the lift rotates thus assuring lift stability through 180 degrees of overarm rotation.

2. A. A lift mechanism using powered linear actuator as the lift drive unit.

B. Said mechanism to be located within the rotating member of the vertical column and be coupled to the lift cable.

C. Said mechanism to assume a complete lock-up mode in the event of a power failure.

D. Lift control afforded by use of a single pole double throw paddle switch, with a spring loaded 3 position, centre off configuration, located within easy reach of the patient at all times.