GB2134949A

GB2134949A - Improvements in road cones or the like

Info

Publication number: GB2134949A
Application number: GB08303591A
Authority: GB
Inventors: Barry Mills
Original assignee: Plascoat UK Ltd
Current assignee: Plascoat Systems Ltd
Priority date: 1983-02-09
Filing date: 1983-02-09
Publication date: 1984-08-22
Also published as: GB8303591D0

Abstract

A road cone which includes a closed ballast cavity in its base portion 2 is formed by dip-moulding from a flexible polyvinyl chloride. The bottom wall 2b of the base portion 2 is moulded integrally with a tubular wall 2c which initially extends externally of the base portion, downwardly away from the conical body portion 1 to enable the cone to be stripped from its internal mould. After stripping, the tubular wall 2c is flexed and folded into the body portion to cooperate with the interior of the body portion 1, and is sealed thereto to form a generally annular ballast cavity. The cavity may be filled with a low cost ballast, for example sand or water, before sealing, through the gap between the upper end of the tubular wall 2c and the interior of the body portion 1, whereafter sealing is effected to permanently close the cavity. <IMAGE>

Description

SPECIFICATION Improvements in road cones or the like The present invention relates to free-standing traffic or road markers or the like, such as road cones, formed from synthetic plastics materials.

The invention is particularly concerned with a synthetic plastics, free-standing traffic or road marker of the type which comprises a hollow body portion extending upwardly from an enlarged, hollow skirt-like base portion. The base portion includes a bottom flange-like wall which extends inwardly from the periphery of the base portion, and defines an opening disposed generally beneath the body portion.

Such markers, and in particular road cones, are used, in large numbers, and since they are prone to damage or loss, it is necessary for them to be mass produced at relatively low cost. Such road cones have previously been formed from polythene, and in order to minimize the quantity of polythene per cone, and therefore minimise the cost per cone, the cones have been formed as relatively thin-walled shell-like structures by rotational moulding. The opening in the bottom wall of each cone is sized to receive the conical body portion of another cone to facilitate stacking or nesting of cones for storage or transport purposes. During moulding, the bottom wall is formed with a re-entrant or upwardly directed shallow lip around the opening which serves to reinforce the bottom wall.The lip also defines with the bottom wall a relatively shallow channel extending around the opening within the base portion.

Due to their relatively light weight, such prior road cones tend to be readily moved or toppled over, for example in windy conditions, or when struck. Various attempts have been made to ballast or weight such cones in an economical manner, for example by filling the channel in the base portion with concrete, sand or water.

However, if such a cone is struck, the ballast can become dislodged and fall out of the opening, reducing or eliminating the stabilizing effect of the ballast, and possibly causing a hazard to road users.

It is an object of the present invention to provide a marker of the type specified, and particularly a road cone, which may be mass produced at relatively low cost, and may be ballasted in a manner which effectively overcomes the previously mentioned disadvantages.

According to one aspect of the present invention, there is provided a marker of the type specified, wherein the bottom wall is provided, around the opening therein, with an integral tubular wall which extends inwardly of the base portion towards the body portion, and cooperates with the interior of the marker to form an effectively closed or sealed cavity containing or adapted to contain ballast.

According to another aspect of the present invention, there is provided a method of manufacturing a marker as just defined, which comprises moulding the marker from a flexible synthetic plastics material with the tubular wall initially extending externally of the base portion, away from the body portion, and folding the tubular wall into the body portion to cooperate with the interior of the marker and form said cavity.

By moulding the marker, for example a road cone, with the tubular wall or sleeve initially projecting externally of the base portion instead of internally of the base portion, the road cone may be readily and economically mass-produced by known dip moulding techniques, using a male mould or core which is dipped into a plastisol, such as polyvinyl chloride plastisol (i.e. a dispersion of pulverent polyvinyl chloride in a compatible liquid plasticiser which is cured or gelled on heating to a high temperature).After each road cone moulding is stripped off its mould, which is facilitated by the resilient or flexible nature of the PVC moulding, the external tubular wall is simply flexed in and reversed, and the upper rim of the then internal tubular wall is sealed, for example permanently bonded, to the interior of the cone, for example to the interior of the conical body portion at its juncture with the base portion.

The ballast, which may be water, sand, or other relatively low cost fluent material, may be introduced into the cavity before sealing, or before completion of sealing, between the rim and body portion, so that the ballast is permanently sealed in place during manufacture.

Alternatively, the ballast may be introduced subsequent to sealing of the rim to the body portion, via a filling opening in the base portion.

The filling opening may be provided with a removable closure, or may be permanently sealed after introduction of the ballast.

The rim of the tubular wall is preferably engaged and sealed in an annular recess in the lower end of the body portion so as to form a substantially smooth downward continuation of the internal surface of the adjoining region of the body portion. This prevents or minimises snagging between adajcent cones when stacked, and in particular prevents snagging of the external reflective sleeves which are often fitted to the body portion of road cones.

In order that the invention may be more readily understood, one embodiment thereof will now be described with reference to the accompanying drawings, in which: Figure 1 is a side view of the road cone moulding prior to turning in of the tubular wall; Figure 2 is a side view of the same moulding, partially sectioned on the line AA of Figure 1; Figure 3 is a plan view of the moulding shown in Figures 1 and 2; Figure 4 is an enlarged fragmentary view of the lower part of the moulding shown in section in Figure 2; Figure 5 is a side view of the road cone formed from the moulding shown in Figures 1 to 4, after turning in of the tubular wall; Figure 6 is a side view of the same road cone, partially sectioned on the line BB of Figure 5; Figure 7 is a plan view of the road cone shown in Figures 5 and 6;; Figure 8 is an enlarged fragmentary view of the portion of the road cone shown ringed in Figure 6.

A road cone moulding or shell is initially formed to the configuration shown in Figures 1 to 4. The moulding is produced by a known dip moulding technique, in which a male mould or core having the same shape as the interior of the moulding, is heated, dipped into a polyvinyl chloride plastisol, and removed from the plastisol to allow the plastisol layer or coating on the mould to cure. The moulding thus formed, which is relatively flexible, is then stripped from the internal mould.

As will be seen, the moulding comprises a generally conical hollow portion 1 extending upwardly from a hollow skirt-like base 2 having, in plan, the outline of a regular polygon (Figure 3).

The body portion 1 is stepped in the region of its root or juncture with the top wall 2a of the base part 2 to form an internal annular recess 1 a of a depth approximating the wall thickness of the moulding. The bottom wall 2b of the base portion, in its initially moulded condition, is inclined downwardly towards its juncture with a downwardly and outwardly projecting integral tubular wall or sleeve 2c. The wall 2c is generally cylindrical, and its lower end is open, and may be trimmed if required.

The dimensions of the base portion 2, and in particular the radial extent of the bottom wall 2b and the diameter of the tubular wall 2c are such that they may be stretched, without permanent deformation or damage, over the enlarged portion of the mould defining the base portion, when the moulding is stripped from the mould. The dimensions of the base portion are also such that, when the tubular wall 2c is flexed and turned in, the tubular wall will project internally, upwardly as shown in Figure 6, with its upper rim 2d located in the annular recess 1 a. The reversal of the tubular wall also causes the bottom wall 2b to flex from its downwardly inclined position as shown, in Figure 2, to a generally horizontal position. Thus, the reversal of the tubular wall forms a generally annular cavity 3 in the base.

The cavity 3 is then filled with ballast, for example water mixed with a gelling agent, for example inserted via a pipe inserted between the flexible rim 2d and the recessed portion I a of the body portion 1. After the cavity has been completely filled, the rim 2d is permanently bonded to the recessed portion 1 a as shown in Figure 8, for example by ultrasonic welding or an adhesive, to seal off the cavity.

If required, a reflective frusto-conical sleeve (not shown) may be secured to the exterior of the conical body portion 1, located against the external step formed by the recessed portion 1 a.

As will be apparent from Figure 8, the recessing of the rim 2d ensures that it does not stand proud of the internal surface of the conical body portion 1, so that when a number of cones are stacked or nested together, with the conical body portion of one cone extending up through the tubular wall 2c of a superimposed cone, and into the conical body portion of the latter, the reflective sleeve of the lower cone will not snag on the rim 2dof the superimposed cone.

From the foregoing, it will be seen that there is provided a particularly advantageous ballasted road cone which is relatively inexpensive and simple to produce. The provision of the tubular wall 2c, which is turned in and sealed to the interior of the conical body portion after moulding, enables the cone moulding or shell to be simply produced by a dip moulding technique. Since the cone is moulded from PVC and is therefore relatively flexible, and since the ballast is sealed into the cavity 3, the risk of damage to the cone, and loss of ballast, if the cone is struck or run over, is considerably reduced.

The addition of a gelling agent to the water ballast, although not essential, causes the water to gel inside the cavity, and minimises swilling or slopping of the water around within the cavity 3 if the cavity is not completely filled.

It will be understood that various modifications may be made without departing from the scope of the present invention. For example, the road cone may be ballasted with water devoid of gelling agents, or with other ballast materials or mixtures of materials which are liquid or fluid, at least during introduction into the cavity. For example, sand or cement may be employed as the ballast.

The ballast may be introduced before or during bonding of the tubular wall 2a to the body portion 1, or may be introduced after partial bonding, but before a complete circumferentially continuous bond has been produced. Alternatively, the ballast could be introduced into the cavity after sealing, through an appropriate opening or openings in the base portion, which openings may subsequently be permanently sealed, or closed by removable closure means to permit emptying and/or refilling.

Whilst the rim 2d is preferably permanently bonded to the body portion, it could alternatively resiliently and sealingly engage the latter.

Although, in the illustrated embodiment, the rim 2d engages in a recess lain the body portion, the rim could alternatively engage an un-recessed part of the body portion, adjacent the root of the latter or elsewhere, or could alternatively cooperate with the interior surface of the base portion.

As shown in Figure 6, the tubular wall 2c is generally cylindrical, at least below its joint line with the body portion. However, it could alternatively be frusto-conical so as to form a continuation of the conical base portion. Whilst specific dimensions have been given in the accompanying drawings, it is to be understood that they are exemplary, and that other dimensions and combinations of dimensions may be employed.

Although the illustrated road cone is moulded from PVC, other synthetic plastics materials may be employed provided that they possess the necessary flexibility to enable the tubular wall 2c or equivalent to be turned in to close the cavity.

Although the illustrated embodiment is directed to a road cone, the invention may be applied to other types of free-standing road or traffic markers, or other articles, which require or would benefit by ballasting.

Claims

1. A free-standing marker or the like, comprising a hollow body portion extending upwardly from an enlarged, hollow skirt-like base portion, the base portion including a bottom flange-like wall which extends inwardly from the periphery of the base portion, and defines an opening disposed generally beneath the body portion, wherein the bottom flange-like wall is provided, around the opening therein, with an integral tubular wall which extends inwardly of the base portion towards the body portion, and cooperates with the interior of the marker to form an effectively closed or sealed cavity containing or adapted to contain ballast.

2. A marker as claimed in claim 1, wherein the upper end portion of the tubular wall cooperates with the interior of marker, said upper end portion engaging in an annular recess in or adjacent the lower end of the interior of the body portion, so as to form a substantially smooth downward continuation of the internal surface of the adjoining region of the body portion.

3. A marker as claimed in claim 1 or 2, wherein the upper end portion of the tubular wall is permanently bonded to the interior of the body portion at or adjacent the lower end thereof.

4. A marker as claimed in claim 1, 2 or 3, dipmoulded from polyvinyl chloride.

5. A marker as claimed in any preceding claim, wherein a filling opening is provided in the base portion for the insertion of ballast.

6. A marker as claimed in any preceding claim, which comprises a road cone.

7. A one-piece road cone substantially as hereinbefore described with reference to the accompanying drawings.

8. A method of manufacturing a free-standing marker as claimed in claim 1, which comprises moulding the marker from a flexible synthetic plastics material with the tubular wall initially extending externally of the base portion, away from the body portion, and folding the tubular wall into the body portion to cooperate with the interior of the marker and form said cavity.

9. A method as claimed in claim 8, which includes dip moulding the marker.

10. A method as claimed in claim 9, which includes dip moulding the marker from polyvinyl chloride.

1 A method as claimed in claim 8, 9 or 10, which includes permanently bonding the upper end portion of the inturned tubular wall to the interior of the body portion at or adjacent the lower end thereof.

12. A method as claimed in claim 1 which includes filling the cavity with ballast before sealing or completion of sealing, by inserting the ballast between the upper end portion of the inturned tubular wall and the body portion, and then carrying out or completing the sealing operation, so that the ballast is permanently sealed in place during manufacture of the marker.

13. A method as claimed in any of claims 8 to 12, which includes introducing the ballast through a filling opening in the base portion, and subsequently releasably or permanently sealing the fil!ing opening.

14. A method of manufacturing a one-piece road cone substantially as hereinbefore described with reference to the accompanying drawings.