GB2401600A

GB2401600A - Rollable loading ramp

Info

Publication number: GB2401600A
Application number: GB0310798A
Authority: GB
Inventors: Edmund O'keeffe
Original assignee: Individual
Current assignee: Individual
Priority date: 2003-05-12
Filing date: 2003-05-12
Publication date: 2004-11-17
Also published as: GB0310798D0

Abstract

A ramp for bridging between two surfaces and which is operable between rolled-up and extended positions. The ramp has a plurality of generally rectangular moulded plastics treads 10 pivoted together in series, each tread including two metal inserts 22 disposed adjacent opposed side edges 13,14 of the tread 10 and providing lugs 15 projecting towards the next adjacent treads. Hinge pin (16, Fig 3) pass through bores provided in the projecting lugs 15 of adjacent treads. Each tread has an upstand 23,24 adjacent its side edges 13,14 and engageable with corresponding upstands 23,24 on the adjacent treads, to limit pivoting movement of the treads in one sense but permitting the ramp to be rolled up by allowing the treads to pivot in the opposite sense.

Description

LOADING RAMP

This invention concerns a ramp suitable for use in bridging between two surfaces, in order to facilitate the movement of an article from one surface to the other. In particular, this invention relates to a ramp which is operable between extended and rolled-up positions, whereby when in the latter position the ramp is more readily stored or carried from place to place.

Loading ramps of various kinds have been designed to permit the movement of a wheeled vehicle over an obstruction. For example, a loading ramp may be used to facilitate the loading of a motor vehicle with goods carried on a wheeled truck, the ramp bridging the gap between the ground and the loading deck of the vehicle. Similarly, ramps may be used with trains, to facilitate the movement of a load on a wheeled truck between a platform and a carriage or wagon of the train. Further, loading ramps are frequently provided for wheelchairs, to facilitate access which could not otherwise be achieved by a wheelchair user.

Loading ramps for the above purposes may be made in one piece with a sufficient length to bridge a typical gap. However, a typical loading ramp may be between two and four metros long and so is somewhat unwieldy, awkward to store and difficult to transport from place to place, especially if the ramp is to be carried in a car along with a wheelchair. Consequently, there have been proposals for portable loading ramps which are made in two or three elongate sections hinged to each other and so which may be folded into a shorter overall length, a suitable locking mechanism being provided to prevent the ramp collapsing in use. Further, in US-2002/0088065-A1, there is described a - 2 loading ramp which may be rolled up in order to make the ramp easier to transport. However, to impart sufficient strength to the ramp, it is made of metal sections each of a significant depth, and so is relatively heavy with complex joints to give sufficient strength against collapsing when extended.

Even so, a tie is provided below the ramp which normally is in a convex shape (when viewed from above) in order to resist collapsing movement under load.

It is a principal aim of the present invention to provide a ramp which is operable between rolled-up and extended positions, to permit easy storage or to make the ramp more portable.

According to this invention, there is provided a ramp operable between rolled-up and extended positions, which ramp comprises a plurality of similar generally-rectangular substantially planar treads pivoted together in series, each tread being of a moulded plastics material but including at least one metal insert moulded therewithin so as to be adjacent two opposed side edges of the tread and providing lugs projecting towards the adjacent treads of the series, adjacent treads being hinged together by means of respective hinge pins passing through bores provided in the respective projecting lugs of adjacent treads, and each tread having a respective upstanding portion adjacent said side edges and engageable with the corresponding upstanding portions of the adjacent treads thereby to limit pivoting movement of the adjacent treads in one sense when the treads are substantially co-planar, but permitting the treads to pivot in the opposite sense so that the ramp can be rolled up.

It will be appreciated that with the ramp of this invention, there is a plurality of treads each of which is predominantly of moulded plastics material, - 3 but including at least one metal insert in order to give sufficient strength to the region of the treads which are hinged together to form the complete ramp. The manufacturing cost of such a ramp may be significantly less than with an all- metal ramp and further, by appropriate selection of materials and design parameters, it might also be possible for the ramp to have a reduced weight as compared to an all-metal ramp.

Though it would be possible to provide a single metal insert, typically having two major portions disposed adjacent the two opposed side edges of the tread and linked together by one or more cross-members, it is highly preferred that each tread has two quite separate metal inserts, one adjacent each of the two said side edges of the tread, respectively. All such metal inserts may be essentially of the same design and so provide the projecting lugs which are hinged together to permit interconnection of the treads, thereby to form the complete ramp.

Preferably, each metal insert extends into the upstanding portion of the tread, so as to impart sufficient strength to that upstanding portion. Further, each insert may be provided with a stub which projects from only one side of the upstanding portion towards the upstanding portion of the next adjacent tread and which is receivable in an opening in the upstanding portion of the next adjacent tread. Advantageously, the metal insert of the next adjacent tread has an aperture therein, to receive the stub in a close sliding fit when the ramp is in its extended position. In this way, greater stability may be imparted to the ramp, when in its extended position.

A ramp of this kind will have an upper surface which in use will face generally upwardly, though of course the ramp may lie at a significant angle to the horizontal. The hinge pins may lie generally in the plane of the upper surface of the ramp and then the upstanding portions of the treads will project generally upwardly from the treads. In this way, when the ramp is moved to its extended position, those upstanding portions will abut each other and so resist downward bending of the ramp by an applied load. However, the ramp may be rolled up by relative hinging movement of the treads from one end of the ramp, rolling those treads from below the length of the remaining part of the ramp until 0 the entire ramp has been rolled into a generally circular configuration.

Preferably, the two long edges of each tread which extend between said side edges are provided with projecting tabs, the tabs of one long edge being interengageable with the tabs of the opposed long edge of the next adjacent tread, when the ramp is in its extended position. Provided the tabs are appropriately designed, the tabs will permit a load applied to one tread to be distributed to the adjacent treads as well, so reducing the absolute strength requirement for any one tread.

Though it is envisaged individual hinge pins will be used to interconnect the corresponding lugs of the metal inserts of adjacent treads, a single hinge pin could be provided and which extends between the opposed side edges of the treads, parallel to their long edges. In this case, that single hinge pin may interconnect the projecting tabs of the adjacent treads so imparting greater strength in the central region of each tread.

Advantageously, each metal insert is formed in one piece to provide a pair of spaced-apart parallel side plates which define the interengageable lugs.

To permit the lugs of adjacent sections to overlie with the respective hinge pin bores in register, the lugs on one end of the metal insert may be stepped inwardly towards each other or outwardly away from each other by a distance equal to twice the thickness of the metal defining the inserts. Then, the lugs may be interfitted and a hinge pin passed through the aligned bores.

The weight of the ramp may be reduced by providing apertures through each tread. Further, such apertures will have the advantage of increasing grip as well as permitting the draining of water and removal of debris from the extended ramp.

The tread at at least one end of the ramp may be configured such that when the ramp is fully extended, that tread lies at a relatively shallow angle to the other treads. This may be achieved by appropriate configuration of the upstand of that end tread and may facilitate access on to the ramp by a wheeled vehicle, wheelchair or the like.

By way of example only, one specific embodiment of ramp of this invention will now be described in detail, reference being made to the accompanying drawings in which: Figure 1 is an isometric view of the embodiment of ramp, in an extended position; Figure 2 is a detail view on an enlarged scale of two adjacent treads of the ramp of Figure 1; Figure 3 is a side view of the ramp of Figure 1, when extended; - 6 Figure 4 is a side view of the ramp of Figure 1, when rolled up; Figure 5 shows an alternative arrangement for the hinging together of two adjacent treads; and Figures 6 and 7 are respectively isometric and end views on a metal insert as incorporated into each moulded tread of the ramp.

The embodiment of ramp shown in the drawings is assembled from a plurality of treads 10 all of identical form except for the end tread 11, and all of which are hinged together in series so as to form an elongate structure as shown in Figures 1 and 3. However, the ramp may be rolled up for portability purposes as shown in Figure 4, as will be described in greater detail below.

Each tread of the ramp comprises a plastics material moulding but including two metal inserts 12, one at each side edge 13,14 respectively. The metal inserts serve to provide projecting lugs 15 by means of which adjacent treads may be hinged together, using hinge pins 16 passing through the holes of the interfitting lugs of adjacent sections, as will be described in greater detail below.

Each tread has a main area 18 of a generally rectangular shape and which has a plurality of apertures 19 therethrough, both to reduce the weight of the tread and to facilitate the removal of unwanted matter on the ramp, when in use. The apertures further serve to provide grip for a user, especially when the ramp is inclined. Respective flanges 22 depend downwardly from the side edges 13,14 and from the long edges 20,21 extending between those side edges, which flanges are moulded integrally with the main area 18. Further, along the two side edges 13,14, there are block-shaped upstands 23,24 projecting above the surface of the main area 18 and within which the metal inserts are embedded, during the moulding operation.

Each long edge 20,21 of each tread is provided with four projecting tabs each of which has a first part 26 of an upwardly-directed channel section and a second part 27 of an inverted channel section, the positions of the tabs along the length of the opposed long edges being such that the first part 26 of one tab may interengage with the second part of the corresponding tab on the next adjacent tread, as shown in Figure 2. In this way, the tabs of the long edges of two adjacent treads will interengage when the ramp is fully extended, so permitting a load applied to one tread to be distributed to the next adjacent tread.

Rather than using two separate hinge pins 16, one at each side of each tread respectively, a single hinge pin 28 may be used and which extends from one side edge to the other side edge of the tread, along the long edge 20 of the tread and so also along the long edge 21 of the next adjacent tread, as shown in Figure 5. In this case, the single hinge pin 28 may also pass through the projecting tabs 25 of the adjacent treads so as to impart greater stability to the ramp, when extended.

Figures 6 and 7 show one of the two metal inserts which are incorporated in the moulding of each tread of the ramp. Each insert 12 is formed from sheet metal by a bending and punching operation, so as to have a pair of parallel side plates 30,31 held spaced apart by two sections 32. Folded downwardly from each section 32 is a flange 33 having a hole 34 formed therein. The sections 32 and flanges 33 will be disposed within the upstands 23,24 of the tread, when moulded. At the lower part of the insert, each side plate 30,31 provides the two lugs 15, projecting in opposite directions generally in the plane of the respective side plate. Each such lug has a through-bore 35, for receiving the respective hinge pin 16 when the ramp is assembled.

In order to permit the interengagement of the two lugs 36 at one end 37 of one insert with the two lugs 38 at the other end 39 of the next adjacent insert, the two lugs 36 are deflected inwardly, each by the thickness of the material from which the insert is made, as shown in Figure 7. Then, the two lugs 36 may fit between the two lugs 38 of the next adjacent insert so that the inserts at 0 one side of the assembled ramp will all be in alignment with each other.

As shown in Figures 6 and 7, the insert is provided with various perforations 40, to reduce the weight of the insert without significantly reducing its strength, for the intended purpose.

As mentioned above, the ramp is assembled from a plurality of treads 10 by fitting hinge pins 16 through the interfitting lugs 36 and 38 of adjacent treads.

At one end of the ramp,'an end tread 11 is similarly hinged to the next adjacent tread 10, the end tread 11 differing in the shape of its upstand, such that end 3 tread 11 lies at an angle to the remaining treads 10, thereby to facilitate access to the ramp. The ramp may be rolled up as shown in Figure 4 by hinging each tread in turn in a clockwise direction (referring to Figures 3 and 4), starting with tread 10 at the end of the ramp remote from end tread 11. The rolling up of the ramp may continue until it is essentially wholly formed into a generally circular roll, as shown in Figure 4. - 9 -

When the ramp is to be used, it may be unrolled into its extended configuration. Hinging movement of each section in a counter-clockwise direction during this unrolling action is limited by the interengagement of the upstands 23,24 at each side of the ramp of one tread, with those of the next adjacent treads. Sufficient strength is imparted to those upstands by virtue of the metal inserts within those upstands and by the flanges 33 in particular, of those inserts.

Though not shown in the drawings, a stub may project from one flange 33 of one insert and which is receivable in the hole 34 in the flange of the insert of the next adjacent tread, to increase the stability of the ramp, when extended.

Such a stub must appropriately be profiled to permit the interengagement of the stub with the hole of the next adjacent tread during the unrolling action.

Typically, therefore, the stub will have a tapering profile.

The upstands 42 of the end tread 11 differ slightly from those of the other treads 10, in that the end faces 43 of the upstands 42 are not precisely perpendicular to the main area 18 of the tread, but rather are inclined at a small angle of typically 5 to 10 to the perpendicular. Thus, those upstands 42 will abut the next adjacent upstands 23,24 only when the main area of the end tread 11 lies at a corresponding angle to the main area of the next adjacent tread.

To allow for manufacturing tolerances and wear in use, the end faces of the upstands 23,24 may be slightly out of parallel and at a slightly greater separation than the distance between centres of the holes through the projecting lugs 36,38. In this way, the ramp when manufactured and when first - 10 extended may not be precisely linear but may have a slight convex form when viewed from above, as shown in side view in Figure 3. Then, on loading the ramp or after an extended period of use, the ramp may deflect to be of a more linear form. - 1 1

Claims

1. A ramp operable between rolled-up and extended positions, which ramp comprises a plurality of similar generally-rectangular substantially planar treads pivoted together in series, each tread being of a moulded plastics material but including at least one metal insert moulded therewithin so as to be adjacent two opposed side edges of the tread and providing lugs projecting towards the adjacent treads of the series, adjacent treads being hinged together by means of respective hinge pins passing through bores provided in the respective projecting lugs of adjacent treads, and each tread having a respective upstanding portion adjacent said side edges and engageable with the corresponding upstanding portions of the adjacent treads thereby to limit pivoting movement of the adjacent treads in one sense when the treads are substantially co-planar, but permitting the treads to pivot in the opposite sense so that the ramp can be rolled up.

2. A ramp as claimed in claim 1, wherein each tread has two metal inserts disposed one adjacent each of said two side edges, respectively.

3. A ramp as claimed in claim 1 or claim 2, wherein the metal inserts extend into the upstanding portions of the treads.

4. A ramp as claimed in claim 3, wherein each metal insert provides a face which supports the part of the associated upstanding portion which engages the corresponding upstanding portion of the next adjacent tread.

5. A ramp as claimed in claim 3 or claim 4, wherein each insert is provided with a stub which projects towards the metal insert of the next adjacent tread and is receivable in an opening therein when the ramp is extended. - 12

6. A ramp as claimed in any of the preceding claims, wherein the two long edges of each tread extending between said side edges are provided with projecting tabs, the tabs of one long edge being interengageable with the tabs of the other long edge of the next adjacent tread.

7. A ramp as claimed in claim 6, wherein a single hinge pin extends between the co-operating lugs of adjacent treads at both of said two opposed side edges of each tread.

8. A ramp as claimed in claim 7, wherein the single hinge pin interconnects the projecting tabs of adjacent treads.

9. A ramp as claimed in any of the preceding claims, wherein each metal insert provides a pair of spaced-apart parallel side plates which together define the interengageable lugs projecting from the tread.

10. A ramp as claimed in claim 9, wherein there are two spaced-apart interengageable lugs at each end of each side edge of a tread, the spacing 1s between the lugs at one end being different from the spacing of the lugs at the other end whereby the lugs of adjacent treads may interfit.

11. A ramp as claimed in any of the preceding claims, wherein apertures are provided through each tread primarily to reduce the weight thereof.

12. A ramp as claimed in any of the preceding claims, wherein the tread at one end of the ramp is configured so that with the ramp in its fully extended position, that end tread lies at a relatively shallow angle to the adjacent tread.

13. A ramp as claimed in claim 12, wherein the face of the upstanding portion of the end tread and directed towards the upstanding portion of the next - 13 adjacent tread lies in a plane out of perpendicular with the main area of the end tread.

14. A ramp as claimed in any of the preceding claims, wherein the end faces of the upstanding portions of each tread and which abut the corresponding upstanding portions of the next adjacent treads all lie out of a true perpendicular plane with respect to the corresponding tread whereby when in its fully extended position, the ramp takes up a slightly convex form, when viewed from above.

15. A ramp as claimed in claim 1 and substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings. I