AU694019B2

AU694019B2 - Motorized towing vehicle

Info

Publication number: AU694019B2
Application number: AU52457/96A
Authority: AU
Inventors: Mervin Dann
Original assignee: JANOCH IND Pty Ltd
Current assignee: JANOCH INDUSTRIES Pty Ltd
Priority date: 1995-05-22
Filing date: 1996-05-22
Publication date: 1998-07-09
Anticipated expiration: 2016-05-22
Also published as: AU5245796A

Description

P/00/011 Regulation 3.2

AUSTRALIA

Patents Act 1990 COMPLETE SPECIFICATION I 1 1 Ir I

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1 II I1 I FOR A STANDARD PATENT

ORIGINAL

Name of Applicant: Actual Inventor(s): Address for Service: Invention Title: TO BE COMPLETED BY APPLICANT JANOCH INDUSTRIES PTY LTD MERVIN DANN A.P.T. Patent and Trade Mark Attorneys GPO Box 772, Adelaide, SA 5001 Motorized Towing Vehicle Details of Associated Provisional Application(s) No(s) PN3108 dated 22nd May 1995 The following statement is a full description of this invention, including the best method of performing it known to us:- 2 The present invention relates to a towing vehicle that can be used to tow a trolley and has particular application for transportation of hospital beds.

The invention will largely be described with reference to a hospital bed however it is to be undcrstood that other applications are also encompassed by this invention.

Hospitals are generally arranged so that certain facilities, for examnple operating theatres, are located at disparate points throughout the hospital, largely because only very few of these facilities can be provided as a result of the considerable expense of providing themn.

As a consequence considerable shifting of patients is required. Most hospital beds are, as a consequence supported on castors, so that the beds themselves can be moved from place to place. The hospital beds however are very heavy and require at least two persons to shift them. Furthermore there are atendant facilities that also often have to be shifted at the samne time as the bed. It will be understood that where a particular patient requires active and ongoing use of a variety of facilities in the hospital that a considerable amount of shifting is required.

This then requires a considerable amount hard manual work. A number of hospital employ orderlies who do such manual work, however as cost constraint are becoming an increasingly important part of hospital administration, there is a tendency for hospitals to no longer employ orderlies and instead nursing staff are required to shift the hospital beds.

To facilitate shifting of patients from one place to another often patients are Shifted to lighter trolleys as a means to lighten the load that is shifted. This naturally necessitates the shifting of patients from the bed to the lighter and this causes some discomfort and distress to the patient, particularly where the patient is seriously ill and finds it difficult or impossible to shift by himself. Even where a lighter trolley is used, often patients can be quite heavy, and it becomes particularly difficult to push or m-anoeuvre patients around the corridors and lifts within a hospital complex.

It is desirable to provide motorised assistance for shifting of patients. One particular constraint on such motorised assistance is that the path taken through the hospital is often quite tortuous and includes usually tight turns at the corners or intersections of corridors, and more difficult to manoeuvre requirements are the size constraints placed onl the motorisation by the size of elevators that are found in lifts.

A number of suggestion have been made for providing powered assistance to shifting of hospital bed and one such suggestion is the provision of a motor mounted onto a hospital bed so that the bed can be driven when and where it is desired. Considerable modification is required for each bed to accommodate the drive, to couple the drive to a driven wheel, and to provide for some means to power the bed, which may take the form of electrical I I 9 3 storage batteries. An example of this suggestion can be found in US patent specification 5083625 by Bleischer. Each bed however does not need to be shifted, because only certain patients need to be shifted frequently, and others only occasionally if at all. There is no certainty as to the number of beds that are to be shifted and when they are to be shifted, accordingly for a hospital to work efficiently many of the hospital beds would need an in-built motor, and storage battery in case the patients might need to be moved from time to time. A choice of the number of motorised bed that would be required would be almost impossible to judge. Additionally most of the time these bed would be idle.

This would be a waste of resources, in terms of the initial purchase, as well as a waste of resources in terms of maintaining the motors, and especially in maintaining the batteries.

A solution to this difficult choice has been suggested by providing a separate motorised towing vehicle to tow hospital beds. Economies can then be achieved by providing a limited number of motorised towing vehicles for the hospital, which can be used to transport a plurality of beds. It has been suggested in US patent number 5337845 by Foster et al to provide a specialised towing vehicle capable of nesting within a hospital bed and capable of motorised towing of the beds. This suggested arrangement requires the construction of specialised beds with particular features to facilitate the docking.

i It has also been suggested in US 3876024 by Shieman et al to provide a motorised towing vehicle that can be used to tow hospital beds of current construction types. The connection is by means of two pivotable arms connecting to upright posts of the bed. This suggestion has a disadvantage as does the US 5337845 that durimn towing all of the castors of the bed are still in contact with the ground. Each castor has slightly different weights bearing onto the ground, and will tend to impart a different steering direction onto the bed. This means that control of the bed during towing is quite difficult. US 5337845 suggests to urge the J 25 driven wheel downwardly under the influence of a ram, however that does not alleviate the i difficulties relating to influences of steering whilst the patient is on the bed and being i, riven.

A further suggestion is made in Swedish patent 7811443-6 by Bengtsson et al, wherein a motorised towing vehicle is provided that connects with a transverse member of one end of the hospital bed, and lifts the transverse members so that one end of the hospital bed is lifted. This alleviates the difficulties of controlling the hospital bed in that castors of one end only of the bed are ground engaging during towing. The Swedish suggestion however, in common with the suggestions made in US 3876024 and US 5337845 have the driven wheel in a fixed position, and under the centre or at least towards the centre of the hospital bed. This is said to assist in r-ducirg the turning circle of the bed. Where tight turns are to be negotiated however it is found that such a positioning of a wheel 4 makes it impractical to tow the bed because it acts transversely to the direction of the steered wheel which latter wheel acts as a brake in such circumstances. It is however particularly in tight manoeuvring where it is desirable to have motorised assistance because that is where most effort is required in unmotorised arrangements.

V 5 An object of this invention is to provide a motorised towing vehicle for towing a trolley that obviates or minimises at least one of the aforementioned problems in a simple yet effective way, or at least provides the public with a useful choice.

In a broad form and not necessarily the broadest or only form the invention could be said to reside in a motorised towing vehicle for towing a trolley including: one or more idler wheels proximal to a first end of the vehicle and one or S more driven wheels proximal to a second end of the vehicle which stably support the vehicle; steering means adapted to effect steering of the driven wheel or wheels; motor means connected to the driven wheel or wheels and adapted to drive the driven wheel or wheels; Sattachment means adapted to releaseably attach to a trolley, and the vehicle being of such configuration that when a trolley is attached to the attachment means the first end is centralmost to the trolley; control means adapted to effect control of the motor means; and, lift means adapted to effect lifting of part of the trolley when attached by an Send to the attachment means.

i SIn a preferred form the lift means includes a ramp adapted to co-act with a portion of a W trolley such that the trolley may be pushed up the ramp or the vehicle pushed under the jtrolley so that the portion of the trolley bears against the vehicle in a first position and t 25 thereby lifting the trolley, and the attachment means includes detent means to releaseably secure the trolley in the first position.

In another preferred form the attachment means includes a channel shaped portion adapted to co-act with a horizontal member of a trolley, and the lift means is adapted to effect lifting of the attachment means so that when the channel shaped portion is placed beneath the horizontal member and the attachment means lifted the vehicle and the trolley are attached.

Preferably the towing vehicle is articulated so that a driven wheel is connected with a steering tiller and a first part of a vehicle body, and the lifting means and idler wheel are supported by a second part of the vehicle body, such that the first part of the body is pivotable with respect to the second part of the body about an upright steering axis.

Preferably the upright steering axis is centred at about the area of ground contact of the driven wheel.

Preferably the steering arrangement includes a first portion that is rigidly connected with or integrally formed with the first part of the body and extends towards a periphery of the trolley to be towed, the steering arrangement further including a steering tiller pivotable vertically so that a handle at a free end of the tiller can be held at a desired height. Where the first portion of the steering arrangement extends away friom the driven wheel past a peripheral edge of the trolley to be towed, the tiller can be rested against the edge of the trolley.

This has a considerable advantage in that the steering tiller and driven wheel can be o0brought right airound and extends the reach of the tiller such that it facilitates bringing the o t- tiller ight around to the side of a hospital bed or other trolley.

000 15 The driven wheel may take the form of a pair of coupled and spaced apart wheel these 0 0 o: wheels preferably share a common driven shaft. Alternatively, the driven wheel may take I.00 0° to form of a single wheel.

The common driven shaft may be directly coupled to a motor, which is preferably electrically driven, or it may be driven by, for example a belt, chain or gears, from a I 20 separate driving shaft. The use of a belt is preferable because it allows for some slip.

0 0 0 o In a preferably form the attachment means comprises a pair of channel shaped members each separately pivotably supported on a pair of spaced apart arms, the pair of arms connected to a common shaft which is driven to rotate, so that the arms can be raised or lowered. Preferably the common shaft is driven by a ram, which is pivotably connected to a post rigidly extending from the common shaft so as to cause rotation on extension or retraction of the ram.

This arrangement allows for the second part of the motorised towing vehicle to be kept quite low so that the attachment means can engage a low lateral member of the trolley to be towed.

Preferably the ram is electrically driven.

Preferably the vehicle is powered by batteries that are preferably carried in the second part of the vehicle.

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-X J The controls are preferably lo actuating the driving motor is on contact with the drive swit 'i i cated on a handle of the tiller, and preferably a control for a momentary drive switch, so that the vehicle will move only .ch.

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i; i i 1 i r r Preferably the idler wheels are fixed in position, and are preferably spaced apart as wide as 5 is practicable for stability, although it may be advantageous to have the direction of the idler wheel controlled to coincide with the direction of the driven wheels.

To assist with the understanding of the invention one embodiment is illustrated. It is to be understood from the foregoing that the illustrated embodiment of the invention is merely illustrative and in no way restricts the scope of the invention.

10 In the illustrations: Ito f t

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Figure 1 Figure 2 is a side view of the motorised towing vehicle in contact with a hospital bed showing that wheels proximal to one end of the bed are lifted, and showing the relative position of the driven wheels of the towing vehicle, and the steering tiller; is a view from above showing the position of the towing vehicle relative to a towed hospital bed and showing the capacity of the first part of the towing vehicle to swivel relative to the bed and the second part of the towing vehicle; is a view from above showing the position of component parts of the lift means, idler wheels and power supply as located in the second part of the body of the motorised towing vehicle; and, Figure 3 Figure 4. is a partial view from about the centre looking to one side of the second part of the body of the vehicle, showing component parts of the lifting means for lifting the hospital bed and in particular showing the position of the ram, driving a shaft, and lifting arms, the attachment means for engaging the lateral member of a bed and stabiliser bars to stabilise the portion of the attachment means.

Similar reference characters indicate corresponding parts throughout the several views of the drawings.

Dimensions of certain of the parts as shown in the drawings may have been modified and/or exaggerated for the purposes of clarity of illustration.

7 The motorised towing vehicle is useful for towing a trolley Such as a hospital bed The towing vehicle includes a pair of driven wheels and a pair of idler wheels a motor (not specifically shown but positioned within mnotor housing is connected for driving the driven wheels. Attachment means 8) arc provided for attachment to the hospital bed. The attachment means are connected with a lift mneans for lifting the attachment means and the bed. Control means (10) are provided for controlling the operation of the motor and a lift means. A steering mneans (11) is provided for steering the driven wheel relative to the towing vehicle.

The illustrated embodiment is an articulated vehicle having a first part of a body (12) pivotably connected by an upright steering shaft (13) to a second part of the body A steering tiller (15) is pivotably connected to a free end of the first part of the body (12) so that the steering tiller can pivot vertically about a horizontal axis, as is shown by arrow A handle (17) is provided at the free end of the tiller, the handle having two hand grips (18, 19). The free end (20) of the first part of the body (12) extends beyond one end (21) of the hospital bed. This enables the steering tiller (15) to be swung approximately 1800 about the steering shaft (13) when connected to the hospital bed, as shown by arrow (22) in Figure 2. The first part of the body (12) shown in unbroken lines in Figure 2 is such that driven wheels are pointing in the direction o1f the bed, whereas when turned at approximately 900 as shown in broken lines in Figure 2 the driven wheels are transverse to the longitudinal axis of the bed.

The steering tiller is formed so as to be made in three parts, each angled with respect to each other, so that the tiller can be easily pivoted over the top of the housing of the towed vehicle when not in use, such that it lies close to the uppermost parts of the housing.

Accordingly the towed vehicle can be stowed away in a very compact form.

t; r m adi 1s atc n e tn The motor of the illustrated embodiment is mounted away fro a diensatcneig the two driven wheels A driving belt provides a drive between the motor and the driven shaft. The motor is an electric motor and is housed behind housing (6).4 The steering shaft (13) is positioned directly above the centre of contact of the two driven wheels with the ground, so that rotation of the first part of the body is facilitated, and canl be achieved when the towing vehicle is stationary. Because steering is centred about the driven wheels, the manoeuvrability of the towing vehicle is greatly enhanced.

The second part of the body of the vehicle supports the two electrical batteries (30, 31) the two idler wheels and the lift means for lifting the hospital bed. The lift means comprises an electrically powered ram (32) including an electric mnotor (33) a housing (34) housing a piston, from which projects a ram shaft (35) driven by the piston. One end of

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Ii Vi Ii the ram is bolted to the second part of the body by bolt a second end of the ram is pivotably connected to post (37) which post is rigidly connected to a lifting shaft (38) which is common to and connected at respective ends to a first end of a pair of lifting arms (39, 40). The second end of each of the lifting arms is connected to a respective attachment mneans The attachment means comprises a channel shaped metal mnember S(41) which is rubbcr lined The attachment means is pivotably connected to the lifting arm. Adjustable length stabiliser rods (43, 44) are also connected to the attachment mneans to maintain the channel shaped attachment means in a relati,,ely level position throughout the raising or lowering of the attachment members. The stabiliser rod is pivotably connect to the second part of the body.

The channel shaped members can be raised from a very low position because of the pivoting action. The attachment members fit underneath a transverse member of the framne of a hospital bed. On providing a lift, one end (5 1) of the, bed is lifted so that two wheel (52, 53) otherwise engaging the ground are lifted from contact with the ground.

Where the wheels are lifted from the ground the hospital bed is supported by two wheels (54, 55) at a second end of the bed the idler wheels 5) and the driven wheel Generally wheels of a hospital bed are castor wheels and are free to swivel in the direction in which they point.

The control means (10) is located at the free end of the tiller (15) and is located between the two hand grips. The control means (10) comprises controls for the electric motor driving the driven wheels, and the controls include a for-ward-reverse control, so the vehicle can be driven in either direction. A speed control can also be provided, and preferably a limit means is provided which not accessible at the console panel of the control means, so that a maximum speed can be provided. A motor actuation is also provided and preferably is inl the form of a momentary switch, which provides a further measure of safety, so that the vehicle will only be driven when the momentary switch is depressed. A stop switch is also provided so that should there be a malfunction, the motor can be stopped immediately, preferably the stop switch actuates a brake to brake the electric motor. A safety cut-out pad can also be provided so that should the operator of the vehicle become confused and get trapped behind the vehicle when driven in reverse, the pad will tend to come in contact with either the operator or perhaps a wall and will auto reverse the motor. The control panel also has control means for controlling the operation of the lift motor, providing for lifting or lowering of the lift arms.

In operation therefore, the towing vehicle is taken from storage by lifting the steering tiller, and manoeuvring the vehicle to a position undemneath a hospital bed where the channel shaped attachment means are positioned underneath a transverse member of a hospital bed.

4t 9 The lift motor is actuated to lift the wheels (52, 53) off the ground. The bed is manoeuvred by actuating the drive motor. The towing vehicle can be used either to tow the vehicle or to push the bed in front of it, and generally in the direction in which the patient is facing. Where a tight manoeuvre is required the drive wheels can be swung at 900 to the longitudinal axis of the bed, and very tight corners can be negotiated.

Modifications may be made to the towing vehicle to suit other applications. Thus for example the lift means and attachment means may be varied to suit trolleys that have transverse members that are higher off the ground. For example in supermarkets it may be desired to provide a motorised towing vehicle for shifting the items that are for sale throughout the store for stocking the shelves. This process also requires a considerable effort because substantial amounts of stock is loaded onto the trolleys. The aisles of a supermarket are considerably restricted, and often include obstacles and have tortuous i paths that require a considerable amnount of effort to manoeuvre manually, and often result in back injury.

Various features of the invention have been particularly shown and described in connection with the exemplified embodiment of the invention, however, it must be understood that these particular arrangements merely illustrate and that the invention is not limited thereto 1 \and can include various modifications falling within the spirit and scope of the invention.

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Claims

2. A niotorised towing vehlicle as in Clfaima I Wherein hle lift, Ileas is adapted so that, When thie Vehicle, i's attached to lit end of' a trolley, trolley wlwes lit oxitoial to that1 endl of' the trolfey aire, Ii fid off' the irounld.
3. A mootor'isedl towintz vehicle as in C mini I or Claim 2 wherein the attahi-mnmanis is mIounted to tlte vehicle so) tIa, when altched to a trolle, it is stistantialfy central between thie idllet' anld drivenl Wheels. 4 1. A inototisco.l towitg vehicle as in any otne of thie preceding! claims whecrein thle control ineas mid( the totor means are anfapte to effect Controlledl forward and( reoverse drivye of the di el nWheel or Wheels, A m ototrisedl towing vehicle as in any onie orl the precedting climt s Whetei n thle conrol means antI the ivoor means are aaptd to effect variabl speed drive to the driven Wheel ol. wheels,
6. A motorised towing vehicleas1 in any otne of the precedintg cI lains whereini the motor means is anl elctric moto andl thereare battery meatns atdaphted to store antd stipply electrical energy to thle motor mentis,
7. A tuotooised towing vehicle as in any one of' thle preceditng claims whereinl the ttachment. means indltdes a channel shapend pxwont adapted to COWLc wit a horizontal 11 member of a trolley, and the lift means is adapted to effect lifting of the attachment means so that when the channel shaped portion is placed beneath the horizontal member and the attachment means lifted the vehicle and the trolley are attached. i 8. A motorised towing vehicle as in Claim 7 wherein the attachment means includes I 5 an arm attached to a rotatable shaft at one end and to the channel shaped portion at the other, and the lift means includes a substantially horizontally acting ram acting between a fixed portion of the vehicle and a cam attached to the shaft such that extension and retraction of the ram effect rotation of the shaft and thereby lifting and lowering down of the attachment means.
9. A motorised towing vehicle as in Claim 7 wherein the lift means effects increase or reduction in vehicle ride height thereby effecting lifting and lowering down of the attachment means. A motorised towing vehicle as in any one of claims I to 5 wherein the lift means includes a ramp adapted to co-act with a portion of a trolley such that the trolley may be 15 pushed up the ramp or the vehicle pushed under the trolley so that the portion of the trolley bears against the vehicle in a first position and thereby lifting the trolley, and the attachment means includes detent means to releaseably secure the trolley in the first position. I 1. A motorised towing vehicle as in any one of the preceding claims wherein the steering means includes a tiller.
12. A motorised towing vehicle as in Claim 11 wherein the control means has operator actuated controls on or proximal :o a handle of the tiller.
13. A motorised towing vehicle as in either Claim 11 or Claim 12 wherein the tiller is pivotable to a storage position where the space taken by the vehicle is reduced compared with the space taken by the vehicle during use of the vehicle.
14. A motorised towing vehicle as in any one of the preceding claims wherein the vehicle is articulated with a first portion supported by the driven wheel or wheels and a second portion supported by the idler wheel or wheels, and the attachmi'.it means and the lifting means are mounted in the second portion.
15. A motorised towing vehicle as in claim 6 wherein the vehicle is articulated with a first portion supported by the driven wheel or wheels and a second portion supported by the idler wheel or wheels, and the battery means, the attachment means and the lifting r 12 I means are mounted in the second portion and the motor means is mounted in the first portion.
16. A motorised towing vehicle as in either Claim 14 or Claim 15 wherein the driven wheel or wheels have an axis of steerage, and the first and second portion are joined substantially above an axis of steerage.
17. A motorised towing vehicle as in any one of the above claims adapted to be substantially beneath a towed trolley thereby effecting a steerage axis within the horizontal extent of the trolley and substantial minimisation of the space required to manoeuvre the towed trolley.
18. A motorised towing vehicle as in any one of the above claims adapted to tow a hospital bed.
19. A motorised towing vehicle substantially as described herein with reference to the accompanying drawings. Dated this 22nd day of May 1996 JANOCH INDUSTRIES PTY LTD By their Patent Attorneys, A. P. T. Patent and Trade Mark Attorneys 13 ABSTRACT Disclosed is a towing vehicle suitable for towing wheeled hospital beds. The vehicle includes a steerable driven wheel with which motive force can be imparted. In a preferred form the vehicle is articulated and battery powered. Tiller steerage is provide which can be folded to reduce vehicle space requirements for storage. The articulation of the vehicle is substantially above the driven wheel. Attachment means are lifted to engage a portion of a bed thereby securing the vehicle to the bed. I, Lr f tIA