GB2298398A - Demountable directional control device for mobile trolleys - Google Patents

Abstract

A directional control device which is demountable and adjustable for use on a plurality of trolleys, including shopping trolleys. Steering is achieved by pivoting the trolley about the fixed-direction wheel or wheels of the device. The upper attachment 3 is engaged on the trolley rear panel top bar and the self-locking lower attachment 4, engages the trolley rear panel lower bar. The capability of a suitably designed trolley to carry an infant passenger is unimpaired. An optional braking facility may be fitted.

Description

DEMOUNTABLE ADJ USFABLE DIRECTIONAL CONTROL DEVICE FOR MOBILE TROLLEYS This invention relates @o a demountable, adjustable, directional control device for mobile trolleys.

Supermarket-type shopping trolleys are one example ot the potential application o@ the invention. They are used by the customers o@ selfservice establistunents, lor the containmejit ol commodities both before and beyond the payment registers. They are "nesting" in design, to allow trolleys to be linked together tor the two main purposes ot: 1. Minimising stor-age area for quantities of parked trolleys.

2. Economical movement ol a number ol trolleys, by one or few people, from diverse parking points to a central collection area.

In order that a number ol trolleys may be moved in this manner, they are normally constructed with all wheels being ot castor type. A long, unbending train ul trolleys may thus be manoeuvered by virtue ot the infinitely variable directioiaal positions o@ all the wheels.

However, whilst this feature is necessary tor the e@@icient management of trolleys, the incorporation of four castor wheels presents a control difticulty Lo customers. Changes ot direction ot travel, tor example @urning through 90 degrees at the end ot a display aisle, are resisted by the momentum ot tt1e trolley which continues in its original direction and velocity. The user must exert considerable energy to overcome this,in order to initiate a change or direction to a heavily laden trolley.Additionally, ctjanges ol 1 loot characteristics, such as a sloping car park area, present another ditticulty. When traversing across the line ot slope, a laden trolley veers heavily sideways under gravitational @orce, necessitating a crab-wise method of travel to retain control troin the normal handlebar, or- by changing the body position and grip to push from the lower side ot the trolley. Both situatiorls may cause discom@ort or strain to the user.

ibe provision of a fixed-direction wheeled device, about which tire castor- wheels of the shopping trolley may be pivoted with minimunt effort from the user, substantially reduces the risk o@ ergonomic strain when varying the direction o@ momentum ot a laden sbopping trolley.

According to the present invention there is provided a demountable, adjustable, directional control device tor mobile trolleys comprising a wheeled chassis with means ol releasubly securing the chassis without the requirement tor tools to a plurality of trolleys, including most designs ot shopping trolleys, and about which the trolley may be pivoted or turned for dir-ectional control.

A speci@ic embodiment of the invention will now be described by way of example with re@erence to the accompanying drawings in which: Figure 1 shows iri per-spective the directional control device in isolation.

Figure 2 shows in perspective the directional control device attached to a typical shopping trolley.

Figure 3 shows in plan view, side and end elevations, an example of an optional braking device on tire wheel or wheels ol the invention.

Referring to Figure 1, the directional control device comprises an outer tube 1 and a sliding. irrrrer membe@ 2, joined internally by a compression spring (not shown). The sectional prolile prevents the inner member turning in relation to the outer tube. Externally, towards the upper end of the outer tube, is @@ upper a@@achment, shown here as a fixed book 3 with at least one prong.

The lower attachment, shown here as a se@@-locking book 4, with at least one prong, is at @iberty to be positioned anywhere along the outer tube. its construction is sucir that iL deflects under load, so that its aperture, which is ol slight clearairce I rom the outer tube, jams against the pro@@le of the tube.

Optionally, @or other applications, the upper attachnient 3 may be a simple inversion of sliding book 4, to jam when pressed upwards into the trolley member with which it interlaces.

At the base is at least orie wheel 5, shower here without the optional mechanical braking device @an example of which is shown separately in Figure 3).

Referring to Figw-e @, in order to attacir tire directional control device to the shopping trolley, the upper attachment is engaged with tire horizontal upper member 6 of the @ear panel, below the handlebar @, The designed @apabil@ty of the trolley to carry an in@ant, whose @egs protrube through the ori@ices 8 of the rear pane@, on either side of the outer tube of the directional control device, remains unimpaired.

The directional control device is then pivoted about the upper attachment until the lower end of the outer tube contacts the horizontal lower member or tire @ear panel ol the trolley. This action pre-loads the internal spring, pressing the wheel or wheels tirmly down onto the floor. to provide @esistance to side-slip when cornering. The lower, attachment (shown here as a sei@-locking sliding hook which is then lowered through tire vertical. bars ot the @ear panel) is next engaged with the horizontal lower member ot the @ear panel.

Removal is the reverse ol the above process, raising the lower, adjustable attachment to release @@@ sell locking nature, then swinging the lower end ot the outer tube @earwards, away from the trolley until the upper attachment may be disengaged and tire invention removed entir-ely from the shopping trolley.

Referring to Figure @, an optional braking device may be @itted wirich, in this example, works under the action ol a tension spring 10 pulling 8 retardation bar 11 against the surface of the wheel or wheels. The broken lines in the bJde elevation show the position ot the brake in the "off" position, held upwards by the geomtri@ relationship ot the spring anchorpoint 12 to the retardation bar @ulcrum 13.

Claims (9)

1. A demountable directional control device tor mobile trolleys comprising a wheeled chassis with means ol releasably securing the chassis to a plurality ot trolleys, including most designs oi shopping trolleys.

2. A demountable directional control device as claimed in Claim l, wherein the means ol releasably securing tire chassis to a trolley incorporates aa adjustable attachment to @acilitate secure mounting upon trolleys of various design heigh@s.

3. A demountable directional control device as claiiied in Claim 1 or Claim 2, wherein the i@@e@ member is sprung from the outer member to maintain the downward loading of the wheel o@ wheels upon the floor for the resistance ol side-slip, with trolleys ol various design heights.

4. A demountable directional control device as claimed in any preceding claim, wherein the construction prevents the chassis components from turning in relation to each other, i1s order to maintain the fixed- directional integrity of the wheel or wheels.

5. A demountable directional control device as claimed in any preceding claim, about which the trolley may be pivoted or turned tor directional control.

6. A demountable directional control device as claimed in any preceding claim, wherein tire means of releasably securing the chassis to a trolley is without the requirement lor- tools.

7. A demountable directional control device as claimed in any preceding claim which, whilst attached Lo a shopping trolley, does riot impede the desigiied @eatrue ot Ire trolley ti1 applicable@ to carry an infant passenge@.

8. A dernountable directional control device as claimed in any preceding claim, wherein an optional braking mechanism may be lit ted.

9. A demountable directional control device substantially as described herein with reterence Lo Figures 1-3 of Lie accompanying drawings.