AU740864B2 - Device for facilitating the loading of stretcher undercarriages into ambulances - Google Patents

Description

1

AUSTRALIA

Patents Act 1990 COMPLETE SPECIFICATION FOR A STANDARD PATENT Name of Applicant: Actual Inventor: FERNO AUSTRALIA PTY LTD Alan Keith FERRIS Address for Service: Invention Title: CULLEN CO., Patent Trade Mark Attorneys, 240 Queen Street, Brisbane, Qld. 4000, Australia.

DEVICE FOR FACILITATING THE LOADING OF STRETCHER UNDERCARRIAGES INTO AMBULANCES Details of Associated Provisional Application: No. PP4699 filed 16 July 1998 The following statement is a full description of this invention, including the best method of performing it known to us:

TITLE

DEVICE FOR FACILITATING THE LOADING OF STRETCHER UNDERCARRIAGES INTO AMBULANCES BACKGROUND OF THE INVENTION This invention relates to patient transporting equipment, particularly stretcher undercarriages and equipment of a similar nature. The invention is concerned with an arrangement for fitting to the leading end of such equipment in order to facilitate the manual loading of the equipment, either with or without a patient, onto the elevated loading bays of ambulances or other elevated platforms whose heights from the ground or base level on which the transporting equipment is supported can vary. Since the invention is primarily concerned with stretcher undercarriages, it will be described in that context. However, as the invention is by no means limited to use with such equipment, the broader applications and ramifications are to be borne in mind when considering the intended scope of the 20 invention.

TECHNICAL BACKGROUND Stretcher undercarriages typically comprise an essentially rectangular patient support frame with 25 collapsible wheeled leg assemblies enabling the stretcher to be stowed or loaded into the back of an ambulance. To assist such stowage or loading, the leading end of the patient support frame is fitted with wheels so that the undercarriage can slide up over the rear edge of the ambulance loading bay and be slid into the ambulance during simultaneous folding of the wheeled legs.

Difficulties are encountered with the stowage of stretcher undercarriages when the height of the ambulance bay floor is above the central axles of the leading end wheels on the support frame. In such situations, the trailing end of the stretcher undercarriage must be tilted so that the wheels can ride up over the rear edge of the ambulance bay. This places strain on the attendant who must be able to withstand the additional rearwardly directed loads created upon tilting. Strains and stresses are also placed on the patient as well as the stretcher undercarriage itself.

OBJECT OF THE INVENTION It is therefore an object of the invention to devise an arrangement for fitting to stretcher undercarriages and like equipment which obviates or at least ameliorates such difficulties.

SUMMARY OF THE INVENTION According to the present invention there is 15 provided an arrangement for facilitating the loading of a o oo stretcher undercarriage into the loading bay of an ambulance, said arrangement comprising a pair of wheeled devices for fitting to opposed stretcher undercarriage frame members at or near the top leading edges thereof, 20 wherein each said device comprises a pivotable mounting on which a leading wheel and a trailing wheel are coplanarly supported in such a manner that the leading wheel can ride onto an ambulance floor and pivot downwardly allowing the trailing wheel to ride up over the rear edge of the ambulance floor as the stretcher undercarriage is pushed into the bay of the ambulance.

DETAILED DESCRIPTION OF THE INVENTION Preferably, a skid block extends between the leading wheel and the trailing wheel to facilitate the movement of the mounting up over the rear edge of the ambulance floor. The skid block, which can suitably be fabricated from high density plastics material, is typically located so as to extend from the axle region of the leading wheel to a location below the axle region of the trailing wheel. The skid block enables the leading wheel to slide over the rear edge of the ambulance floor to a position where its axle ends up below the axle of the trailing wheel so that the arrangement can pivot and "climb".

The pivotable mounting can be in the form of a pair of closely spaced metal plates, with integrally formed skid blocks, in which the wheels are housed and from which the wheels project. Suitably, the wheels project to such an extent that a major portion of their surface contacting edges is visible. The plates can have any configuration to achieve the desired aim. One particular configuration is an irregular quadrilateral configuration.

Pivoting of the mounting can be effected about 15 a common axle extending through a casting or the like which is fitted onto the, normally tubular, stretcher frame. A limit to the degree of pivoting can be provided by one or more, preferably two stops associated with the mounting. In one form such stops can be pins which 20 extend between the metal plates in the upper region thereof the one pin being located toward the trailing end of the mounting and the other pin being located "obetween and above the axles of the wheels. Upward travel of the mounting can thereby be resisted by the respective 25 pins coming into contact with the tubular stretcher S* frame.

Preferably, the pivotable mounting is arranged in such a manner that the leading wheel is normally maintained in a forwardly projecting location with the mounting extending rearwardly thereof, when the stretcher undercarriage is in a position prior to loading into an ambulance. This arrangement can be achieved by careful balancing of the components or, more preferably, by spring biasing. In this latter instance, a torsion or like spring mechanism can be housed in the circlip and extend about the pivot point to a remote point on the mounting, such as the forward pin stop.

The leading and trailing wheels can be wheels of the type which are conventionally found on stretcher undercarriages. Although not essential, the leading wheel is a smaller diameter wheel than the trailing wheel. This greatly facilitates the design and operation of the device.

The device need not be separately attachable to the stretcher undercarriage by means of the circlip but can be formed as an integral component of the undercarriage during its manufacture. Generally, however, the device will be manufactured and sold as a kit for attachment to existing stretcher undercarriages.

ooeoo As previously mentioned, it is also to be borne in mind that the device is applicable to any load bearing wheeled arrangement which is similarly required to be placed on a raised platform, and that the description in relation to stretcher undercarriages and ambulances is merely by way of exemplification of the inventive concept, as is not limited thereto.

.o DESCRIPTION OF THE DRAWINGS 25 Figure 1 is an elevational view of a stretcher undercarriage incorporating a load facilitating arrangement according to the present invention, Figure 2 is a partial cross-sectional view of one wheeled device of the load facilitating arrangement depicted in Figure i, Figure 3 is an elevational view of the wheeled device depicted in Figure 2 in one orientation, and Figure 4 is an elevational view of the wheeled device depicted in Figure 3 in another orientation.

DESCRIPTION OF PREFERRED EMBODIMENT A preferred embodiment of the invention will now be described with reference to the accompanying drawings, in all of which like reference numerals refer to like parts.

Referring firstly to Figure 1, there is shown a stretcher undercarriage indicated generally by arrow and a load facilitating arrangement indicated generally by arrow 11. The load facilitating arrangement comprises a pair of wheeled devices 12, 13 fitted to the forward upper end of the stretcher undercarriage (by forward end is meant the end which first enters the ambulance) 15 The stretcher undercarriage comprises a tubular oooo framework of conventional design, having a patient support platform 14 defined by longitudinal members S"16 and cross members 17, 18; and a pair of collapsible wheeled supports 19, 20 which are designed to fold up under the patent support platform when it is loaded into an ambulance.

cross-sectional elevation of the wheeled support device 12 is shown in Figure 2 to which reference 25 is now made. The device comprises a leading wheel 21 and a larger diameter trailing wheel 22 supported on respective axles 23, 24 extending between metal plates, only one of which, viz. the rear plate 25a, is illustrated in Figure 2 the other, viz the front plate 25b is illustrated in Figs. 3 and 4.

The metal mounting plates 25a, 25b are pivotally connected by a pin 26 to a housing 27 which is an integral part of a sleeve 28 which in turn is removably attachable to the longitudinal member 16 of the stretcher undercarriage. The housing 27 also accommodates the end of a torsion spring 29 which extends out and around a pin 30 connecting the two metal mounting plates. This pin 30 also acts as a stop by pressing against the longitudinal member 16 to thereby prevent the wheeled support device from rotating anti-clockwise past the position illustrated in Figures 2 and 3.

A second pin 31 similarly acts as a stop but this time to prevent the wheeled device from rotating in a clockwise position too much further than as depicted in Figure 4.

The lower section of each metal mounting plate has an integrally formed skid block 34, 35 of plastics material. The skid blocks extend below the axle 24 of S"the trailing wheel 22 and around the axle 23 of the 15 leading wheel 21.

"In use, the arrangement operates substantially S"as indicated in Figures 3 and 4, to which reference is now made. In these drawings, reference numeral 32 20 indicates the upper rear edge of the ambulance floor onto which the stretcher undercarriage is being loaded. As shown in Figure 3, the floor 33 of the ambulance loading **bay is higher than the normal axle height of a wheel on a conventional stretcher undercarriage. However the 25 leading wheel 21 of the device can easily ride onto the ambulance floor and in so doing enable the trailing wheel 22 to easily ride up and over the rear edge 32 of the stretcher undercarriage in the direction indicated by the large flow arrow in Figure 3, until the position shown in Figure 4 is reached. Simultaneously, the entire device pivots about the pivot axis 26 until both wheels are on the ambulance floor 33. The wheels remain in contact with the floor due to the downward load exerted thereon by the weight of the stretcher undercarriage.

It is to be understood that in the particular embodiment illustrated, which is preferred for situations where the ambulance floor 33 is just below the height range of the leading wheel 21 but above the axle of the trailing wheel 22, the skid blocks 34, 35 assist the wheeled devices 12, 13 to slide over the rear edge 32 of the ambulance to a position below the trailing wheel axle 24 and thereby enable the devices to pivot and climb over the edge.

In this manner, the difficulties encountered with the loading and stowage of stretcher undercarriages of the type previously referred to are obviated with ease and the objectives of the invention are met.

is to be understood that the term "stretcher *.undercarriage" as used throughout the specification is intended to mean the combination of a patient carrying platform and a wheeled collapsible support frame.

Whilst the above has been given by way of illustrative example of the invention, many modifications 20 and variation may be made thereto by persons skilled in the art without departing from the broad scope and ambit of the invention as herein set forth.

e* .oe..i

Claims (7)

1. 3. An arrangement as claimed in claim 2, wherein the skid block is fabricated from plastics material and extends from the axis of the leading wheel to a location below the axis of the trailing wheel.
2. 4. An arrangement as claimed in any one of claim 1 esoe to 3, wherein the diameter of the leading wheel is between and 75% of the diameter of the trailing wheel.
3. 5. An arrangement as claimed in claim 4, wherein the diameter of the leading wheel is approximately 50% the diameter of the trailing wheel.
4. 6. An arrangement as claimed in any one of the preceding claims, wherein the pivotable mounting comprises a pair of closely spaced plates in which the leading and trailing wheels are housed and from which the leading and trailing wheels project.
5. 7. An arrangement as claimed in any one of the preceding claims, wherein the mounting is pivotable on a common axle extending into an attachment to the stretcher undercarriage.
6. 8. An arrangement as claimed in any one of the preceding claims, wherein the degree of pivoting of the mounting relative to the stretcher undercarriage is limited by two pins, the one pin being located toward the trailing end of the mounting and the other pin being located between and above the axes of the wheels.
7. 9. An arrangement for facilitating the loading of a stretcher undercarriage into the loading bay of an ambulance, substantially as herein described with reference to the accompanying drawings. DATED this 12th day of July 1999 FERNO AUSTRALIA PTY LTD By their Patent Attorneys CULLEN CO.