GB2391534A

GB2391534A - A dolly with anti-slip inserts

Info

Publication number: GB2391534A
Application number: GB0218192A
Authority: GB
Inventors: Lee Buchanan Mallan
Original assignee: Linpac Mouldings Ltd
Current assignee: Linpac Mouldings Ltd
Priority date: 2002-08-06
Filing date: 2002-08-06
Publication date: 2004-02-11
Also published as: GB0218192D0

Abstract

A mobile platform or dolly 1 used for moving loads between locations has a loading deck 3 including at least one recess 5 formed in its surface, and at least one resilient insert 9 which has a first part which is complementary to, and located in, the recess and a second part that extends above the first surface to increase the resistance to slipping between the mobile platform 1 and articles loaded directly thereon. The resilient insert 9 can be made of a thermoplastic elastomer or rubber type material. The recess 3 can be a pattern of grooves where at least two of the grooves are in communication, adjoining or intersect. The cross-section of the recess is uniform and can have tapering sides. The recess can be holes, in which case the inserts are studs. The dolly can further have complementary formations to the article to be carried to further prevent slipping, these formations can be grooves on one and ribs on the other.

Description

2391 534

Mobile platform The present invention relates to a mobile platform for moving loads between locations, in 5 particular, but not exclusively, for moving loads within or between industrial or commercial premises. Mobile platforms (which are also known as dollies) are well known in the art. A typical mobile platform includes a loading deck, which is arranged to receive a variety of articles to be moved, and a number of wheels or castors which support the loading deck. Castors 10 are usually preferred to wheels since they allow the platform to change direction more easily.

During transit, such platforms rely on friction between the articles and the upper surface of the loading deck to prevent articles from sliding across the loading deck and falling off the platform. The amount of friction between the articles and the loading deck is sometimes insufficient to prevent relative movement between the articles and mobile platform, since the 15 material used for the loading deck is usually selected on the basis of strength, i.e. its ability to sufficiently support the load.

Some mobile platforms include a frame which is attached to the loading deck and which forms an enclosure, or partial enclosure, around the articles positioned on the loading deck, an example being shown in GO 2334508. The frame reduces the amount of relative 20 movement between the articles being transported and the mobile platform by providing lateral support to the articles. This arrangement prevents the articles from sliding about on the mobile platform during transit.

I lowever, the frames used are typically part of a moulding but may be made from steel or aluminum' and add considerably to the weight and cost of the mobile platform. Also, such 25 frames reduce the surface area of the loading deck available for supporting articles.

Accordingly the present invention seeks to provide an improved mobile platform which mitigates some of the aforementioned problems.

According to one aspect of the present invention there is provided a mobile platform including a plurality of wheels, a loading deck having a first surface arranged for receiving articles to be transported, the loading deck including at least one recess formed in the first surface, and at least one resilient insert which has a first part which is complementary to, an 5 located in, the recess and a second part that extends above the first surface to increase the resistance to slipping between the mobile platform and articles loaded directly thereon.

Preferably the loading deck is substantially planar and is suitably sized to receive and support the articles to be transported between locations. The loading deck is preferably made from a plastics material, such as a polyolefin, and is manufactured, for example, by 10 rotational or injection moulding, and is supported above the floor by a plurality of wheels.

It is to be understood that the term "wheels" as used herein encompasses wheels, castors, rollers and similar elements. Advantageously the recess(es) in the first surface ofthe loading deck can be formed during the moulding process.

Alternatively the loading deck can be made from aluminium or steel and the recess(es) can 15 be formed by machining, pressing or moulding.

Advantageously each recess includes a groove or a pattern of grooves. Where a pattern of recesses is used some of the recesses can be arranged to be in communication with other recesses, for example, by joining or intersecting the recesses. Preferably at least two recesses; in any pattern of recesses adj oin or intersect each other. The recesses in a pattern of recesses 20 can be arranged in any practical pattern. Preferably the cross-section of the recesses is substantially uniform, however the invention is not limited to this arrangement since the crosssection of the recesses can vary. Also, where a pattern of recesses is used, recesses having different shapes, cross-sections and / or dimensions can be distributed across the loading deck.

25 The insert is arranged to increase the friction between the mobile platform and any articles directly loaded thereon to reduce the amount of slip, or relative movement, between the mobile platform and those articles. Advantageously, the insert is made from a material which I is resilient and reduces slipping. Preferably the insert is made from a material such as rubber or a material that has rubber-like properties. In one preferred embodiment the insert is made 30 from a thermoplastic elastomer. This is particularly advantageous since thermoplastic

elastomers can be moulded into each recess in the loading deck, for example, by injection moulding. Where a pattern of recesses is used and some of the recesses are in communication with each other, and the inserts are cast or moulded in-situ, material is able to flow between the recesses which are in communication with each other.

5 The second part of the insert can be arranged to be substantially level with first surface of the loading deck. Alternatively, the insert can be arranged to have a larger second part that stands more substantially proud of the loading deck to reduce slippage by providing mechanical resistance to movement of the articles.

When in use, articles are placed on the mobile platform and the weight of the articles 10 compresses slightly the inserts under load. Since each insert is made from a resilient material each insert remains in contact with the article when under load. Each insert is arranged to increase the resistance to slipping between the loaded articles and the mobile platform. This can be achieved by selecting a material for the insert that has good frictional qualities such as rubber or thermoplastic elastomers, and optionally adapting the contact, or second, part 15 of the insert, for example, by roughening or shaping. When under load by the articles each insert is supported by the base and side walls of the recess in which it is located.

Advantageously, the arrangement ofthe pattern of recesses, and the inserts located therein, assist the user to position the article on the loading deck. Preferably the pattern includes a recess positioned adjacent to at least one edge of the first surface of the loading deck.

20 Preferably the pattern includes a recess located distally from the edges which is in a spaced relationship with the recess at the edge of the first surface. For example, the recess located distally from the edge can be positioned in a substantially central part of the first surface.

The loading deck may optionally include at least one formation formed in the first surface, which is arranged for engagement with a complementary formation located on an article to 25 be placed onto the loading deck. Preferably the formation is a recess or a castellation. For example, the formation in the first surface is a groove and the complementary formation is a rib located on the underside of an article.

The recess can include a plurality of holes distributed over the first surface of the loading deck, and the insert can include a plurality of studs.

Advantageously the loading deck has a pattern of high friction and low friction areas defined by the provision and absence of said resilient insert' said pattern including a high friction area that extends around the periphery of the loading deck and a low friction area adjacent said peripheral high friction area.

5 Embodiments of the mobile platform will now be described, by way of example only, with reference to the accompanying drawings in which like references indicate equivalent features, wherein: Figure 1 is a plan view from above of a first mobile platform; Figure 2 is a sectional view along a line A-A of the mobile platform of Figure 1; 10 Figure 3 is a detailed sectional view at a larger scale along the line A-A ofthe mobile platform of Figure 1, Figure 4 is a detailed sectional view at an even larger scale of a detail indicated at 'B" in Figure 3; Figure S is a perspective view from above of the first mobile platform; 15 Figure 6 is a detailed perspective view from above at a larger scale of a friction liner in a groove in the first mobile platform; and Figure 7 is a plan view from above of a second mobile platform.

Figure I is a plan view of a mobile platform I (or dolly) which includes a loading deck 3 having a plurality of grooves S in its upper surface 7, a friction liner 9 located in each of the 20 grooves 5, and a pair of wheels 11 and a pair castors 13 attached thereto. The mobile platform 1 may optionally include lifting handles IS.

The loading deck 3 provides a substantially planar platform on which articles to be transported can be loaded. The articles are stacked on the upper surface 7 of the loading deck 3. The loading deck 3 is held in a spaced relationship with the floor by a pair of wheels 25 1 1 and a pair of castors 13 which are attached to the underside of the loading deck 3. The wheels 1 1 and castors 13 are arranged such that the upper surface 7 of the loading deck 3

is substantially parallel to the floor, i.e. the upper surface 7 of the loading deck 3 is substantially horizontal when the platform 1 is on a flat horizontal surface.

The loading deck 3 is typically made from plastics material such as a polyolefin and is typically formed using rotational moulding or injection moulding techniques. Loading decks S 3 made from a polyolefin offer good impact resistance and are easy to clean. Alternatively, the loading deck 3 can be made from aluminium, or steel.

In plan, the upper surface 7 of the loading deck 3 is typically rectangular having a length in the range 600 to 1200mm and a width in the range 400 to 1000mm. l he thickness of the loading deck 3 is typically in the range 40 to 90mm. For example, a preferred loading deck 10 3 has a length of 1200mm, a width of 1000mm and a thickness of 85mm. Other preferred loading deck sizes include a length of 800mm and a width of 600mm, and a length of 600mm and a width of 400rnm.

The pair of wheels 11 and the pair of castors 13 are attached to the underside ofthe loading deck 3. The number of wheels 11 and castors 13 can vary in relation to the size of the 15 mobile platform I and the size of the load to be transported, for example, an embodiment may comprise three or four pairs of wheels 11 or castors 13. However, for most practical arrangements, two pairs of wheels 11, or two pairs of castors 13, or a combination of wheels 11 and castors 13 are used.

The loading deck 3 also includes a skirt 17 which depends from the periphery of the upper 20 surface 7. The skirt 17 can be integrally formed with the deck and serves to increase the rigidity of the loading deck 3, protect the wheels 11 and / or castors 13, and improve the aesthetic appearance of the mobile platform I (see Figures 2 and 3). The loading deck 3 also incorporates ribbing on its underside to increase the strength and the rigidity of the platform 1.

25 Typically two holes are formed in the surface ofthe loading deck 3 to provide lifting handles 15 end to reduce the weight ofthe platform 1. Some embodiments ofthe invention include more than two holes.

The upper surface 7 of the loading deck 3 is profiled to include a pattern of grooves 5.

Typically, the grooves 5 are integrally formed in the upper surface 7 of the loading deck 3

during manufacture and have a uniform cross-section, a depth in the range I to 5mm and a width in the range 2 to 1 Omm. For example, in the embodiment shown in Figures I and 5, the grooves 5 are arranged in quadrants. Each quadrant includes grooves 5 which define a substantially rectangular shape parallel to the edges of the upper surface 7 of the loading 5 deck 3 and seven grooves 5 which run in parallel diagonally across each substantially rectangular quadrant. The grooves 5 in respect of each quadrant form a continuous network.

In each of the grooves S is located an insert comprising a friction liner 9 (see Figures 4 and 6). The friction liner 9 is made from a thermoplastic elastomeric material. The friction liner 9 has a higher coefficient of friction than the material used for the loading deck 3, i. e. has 10 a higher resistance to slipping than the material used for the loading deck 3, and is resilient.

The liner 9 substantially fills each ofthe recesses S. particularly depthwise, and has a crown portion that stands slightly proud of the upper surface 7 of the loading deck 3, for example, by 1 to Mum. The friction liner 9 is preferably welded to the loading deck 3 to hold it in place. Alternatively, the friction liner 9 can be held firmly in place by the groove walls, which 15 may be profiled to have constricted portions and / or tapered sides to improve the retention of the liner 9 in the grooves 5. A suitable bonding agent, such as a cement, may be used to fix the friction liner 9 to the upper surface 7 of the loading deck 3.

The purpose of the friction liner 9 is to reduce relative movement between the mobile platform 1 and the articles loaded thereon by increasing the friction between the articles and 20 the mobile platform I. The friction liner 9 can be formed by injection moulding. The liner 9 can be formed separately in a mould and then fitted into the grooves 5, or alternatively, it may be moulded in-situ in the grooves S. The friction liner 9 can be arranged such that the crown portion stands substantially proud of the upper surface 7 of the loading deck 3. This arrangement additionally provides some 25 mechanical resistance to the movement of articles loaded on the mobile platform 1. For example. an article having ribs located on its underside may be located on the upper surface 7 of the loading deck 3 such that the ribs are positioned on the upper surface 7 between parts of the upper surface 7 that have friction liner 9 material attached thereto. Relative movement between the article and the mobile platform 1 is further reduced by the

mechanical resistance provided by the substantially proud crown portion ofthe friction liner 9 to the ribs.

Additionally, formations, such as recesses and grooves, can be formed in the upper surface 7 ofthe loading deck 3 for engagement with complementary formations, such as ribs, which 5 are located on the underside oftrays / articles which are placed on the loading deck 3. These recesses are not filled with the friction liner 9. The formations may be in the form of castellations in the upper surface 7 of the loading deck 3 for engagement with complementary formations, such as recesses. She formations may also provide some mechanical resistance to movement for articles without complementary formations which 10 are placed on the loading deck 3 and thereby reduce the amount of relative movement between the mobile platform I and the articles placed thereon.

In use, a mobile platform I having a loading deck 3 of an appropriate size and strength to adequately support the articles to be loaded thereon is used. The user positions the platform I on the floor or surface adjacent the articles to be loaded. The articles are then stacked on 15 to the upper surface 7 of the loading deck 3, compressing the friction liner 9 slightly but without losing contact with liner 9 since the liner 9 is resilient. The user pushes / pulls the mobile platform I to the desired location. Alternatively, the platform may be loaded onto a vehicle for transportation. The friction liner 9 significantly reduces relative movement between the articles and the mobile platform 1 during transit, which prevents the load from 20 overhanging the mobile platform, thereby reducing the likelihood of damage to the load, and improves the ease with which the articles can be moved.

I:)ifferentkinds of recesses can be provided. For example, substantially cylindrical bores may be formed in the upper surface 7 of the loading deck 3, in which studs of the friction liner 9 material are located. The studs fill the recesses fully and have crown portions which stand 25 proud ofthe upper surface 7 ofthe loading deck 3. Preferably the studs have profiled crown portions that reduce the amount of residue waste, such as sugar and dust, which collect on them. The bores can be blind bores or through bores.

The bores can be distributed across the upper surface of 7 of the loading deck 3 in any practicable pattern.

A preferred pattern of bores containing friction liner studs 19 is shown in Figure 7. The pattern includes studs 19 distributed in lines 1 9A, l 9B, 1 9C, I 9D parallel and adjacent to the four edges ofthe substantially rectangular upper surface 7 ofthe loading deck 3. The pattern also includes studs distributed in two lines 21 parallel to the shorter sides of the upper 5 surface 7 of the loading deck 3 which cross the upper surface 7 centrally. The central lines 21 of studs, together with the peripheral lines 19 of studs, define two equally sized rectangular areas 23, each of which corresponds to the size of a crate normally carried on the dolly. Within each rectangular area 23 is a substantially rectangular grid 25 of studs. In this case, the grid 25 is generally eighteen by thirteen studs, however, recesses 27 in the 10 upper surface 7 ofthe loading deck, arranged for engagement with complementary features located on the underside of the articles to be loaded thereon, impinge upon the grid 25.

Holes l 5 used as lifting handles also impinge upon the grid 25. Studs are omitted from areas of the grid 25 where the recesses 27 and the holes 15 coincide with the grid 25.

The areas of the loading deck between the regular grids 25 and the surrounding lines 15 l9A,19B,19C,19D,21 of studs are free of friction finer materiel and therefore have a lower coefficient of friction than the areas with studs. For a 800 x 600mrn loading deck 3, the width of the low friction area between the near edge of the grid and the central line of studs 21 is 80mrn, between the near edge of the grid and the peripheral line of studs 1 9A (and for 19B and its near edge) is 130mm, and between the near edge of the grid 25 and the 20 peripheral line 1 9C (and for 1 9D and its near edge) of studs is 90mm.

In use, this arrangement of friction liner 9 material assists the user to position the articles to be loaded on the mobile platform l since the areas without friction liner studs allow the user to slide the tray into position. Typically the articles loaded on the mobile platform 1 are trays, or crates, made from plastics material. The user lifts the tray and usually locates an 25 edge at one end of the underside of the tray onto an area of the upper surface 7 of the loading deck 3 which does not have bores filled with friction liner 9 material, for example, the area between the near edge of the grid 25 and the peripheral line 1 9C of studs. The user then slides the tray across the upper surface 7 of the loading deck 3 towards the peripheral line 1 9C of studs. As the edge of the underside of the tray contacts the peripheral line 1 9C 30 of studs, the studs deform, but remain in contact with the tray since they are resilient, and grip the edge of the tray to locate it in position. The user then lowers the opposite cud of

the tray until it contacts the loading deck 3 and if necessary makes final positional adjustments. The user benefits from being able to slide the tray into position over the lower friction loading deck 3 material and from the higher frictional / mechanical resistance to slippage of the tray offered by the friction liner 9 material.

5 The same benefits to the user can be achieved by replacing the pattern of bores filled with friction liner 9 studs 19A,19B,19C,19D,21,25 by an equivalent pattern of grooves 5 filled with friction liner material 9.

The effectiveness of the arrangement of the pattern of friction liner 9 studs in a polypropylene loading deck 3 (as shown in Figure 7) to retain two types of tray on the 10 loading deck 3 has been tested against other types of platform, under different conditions.

The test is a standard coefficient of friction test and involves placing a tray on the loading deck 3 and raising one end of the mobile platform 1 until the tray slides from the loading deck 3. The angle to which the end of the mobile platform I is raised before the tray slides from its initial position is recorded. The table below indicates the favourable results ofthose 15 tests.

Condition MAXINE Flat based MAXINE Flat based MAXIN1iS Flat based tray on tray on tray on tray on tray on tray on polyprop. polyprop. polyprop. polyprop. wooden wooden loading deck loading loading deck loading loading deck loading a with friction deck with without deck deck liner friction friction liner without liner friction Dry 0.399 0.444 0.295 0.32 0.496 0.426 Wct 0.426 0.647 0. 244 0.336 0.475 0.464 - 20 It will be appreciated that alterations and modifications can be made to the embodiment described above without departing from the spirit of the present invention. For example, an alternative friction liner 9 material can be employed.

The invention is not restricted to a particular arrangement of grooves S. and is not restricted to arrangements of grooves 5 which are in communication with each other. For example, the arrangement may include a number ofunconnected grooves S which run longitudinally, or across the width, of the loading deck 3. The pattern of grooves 5 may be irregular and 5 may include complex geometries. The grooves S can also be arranged around other features which may be included on / in the loading deck 3, such as the lifting handles 15.

The grooves 5 or recesses can be formed in the loading deck 3 at an angle to the upper surface 7 and can have a variety of cross-sections such as 'U', 'V' and 'U' shaped. The grooves S can have tapered sides and constricted portions.

10 The loading deck 3 can be non-planar and may also be made of a number of parts, for example, two halves joined together by welding or bolting.

The mobile platform may have one or more detachable handles to help move the platform.

The invention is also applicable to platforms of the type generally known as "tugs", which typically have two wheels and two feet. These platforms are moved using a handle mounted 15 on a wheel or wheels, which is used to jack up the end of the platiorrn having feet.

Claims

1. A mobile platform including a plurality of wheels, a loading deck having a first surface arranged for receiving articles to be transported, the loading deck including at least one recess formed in the first surface, and at least one resilient insert which has a first part which is complementary to, and located in, the recess and a second part that extends above the first surface to increase the resistance to slipping between the mobile platform and articles loaded directly thereon.

2. A mobile platform according to claim 1, wherein the insert is made from a thermoplastic elastomer.

3. A mobile platform according to claim 1, wherein the insert is made from rubber or a rubber-like material.

4. A mobile platform according to any one ofthe preceding claims, wherein the recess includes a groove.

5. A mobile platform according to any one of claim 4, wherein the recess includes a pattern of grooves.

6. A mobile platform according to any one of the preceding claims, including a plurality of recesses arranged in a pattern, wherein at least two of the recesses in the pattern are in communication with each other.

7. A mobile platform according to claim 6' wherein at least two of the recesses adjoin or intersect each other.

8. A mobile platform according to any one ofthe preceding claims, including a plurality of recesses arranged in a pattern, wherein a recess positioned adj acent to at least one edge of the first surface of the loading deck and a recess located distally from the edges which is in a spaced relationship with the recess at the edge of the first surface.

9. A mobile platform according to any one ofthe preceding claims, wherein the cross section of the recess is substantially uniform.

10. A mobile platform according to any one ofthe preceding claims, wherein the recess has tapered sides.

11. A mobile platform according to any one ofthe preceding claims, wherein the insert substantially fills the recess.

1 2. A mobile platform according to any one of the preceding claims, wherein the loading deck includes at least one formation fonned in the first surface which is arranged for engagement with a complementary formation located on an article to be placed onto the loading deck.

13. A mobile platform according to claim 11, wherein the formation is a recess.

14. A mobile platform according to claim 1 1, wherein the formation is a castellation.

15. A mobile platform according to any one ofthc preceding claims, wherein the recess includes aplurality of holes distributed over the first surface ofthe loadingdeck, and the insert includes a plurality of studs.

16. A mobile platform according to any one of the preceding claims, in which the loading deck has a pattern of high friction and low friction areas defined by the provision and absence of said resilient insert, said pattern including a high friction area that extends around the periphery of the loading deck and a low friction area adjacent said peripheral high friction area.

17. A mobile platform substantially as hereinbefore described with reference to and as illustrated by the accompanying drawings.