IES84083Y1 - A road repair material dispensing head - Google Patents

Description

A Road Repair Material Dispensing Head The present invention relates to a road repair material dispensing head, and in particular a dispensing head capable of dispensing flowable material such as tar or the like, and most particularly for dispensing such materials at temperatures below those conventionally used.

During both road production and repair, one of the most important procedures which must be undertaken in order to ensure the longevity of the road surfaces, and the structural integrity thereof, is the application of a road repair material such as tar or a similar sealant to the various joints within and around the road surface. Where a road is formed from a plurality of concrete slabs, it is necessary to apply a filling of tar between adjacent slabs, and between the outermost slabs and the kerb/pavement or the like. If the road is formed with a continuous upper surface of tarred gravel, it is then generally only necessary to seal the interface between the road surface and the adjacent kerbing/pavement, which will normally be formed from concrete.

The application of the above mentioned sealants provides two very important functions. It is well known that roads/pavements undergo expansion and contraction as a result of temperature variation. If no gaps or joints are left between sections of road/pavement, buckling may occur. However, if gaps/joints are simply created, but left unfilled, incompressible materials such as stones etc. will eventually migrate into the gaps, preventing the requisite expansion. Filling the joints with tar prevents such incompressible materials from entering and lodging within the joints, while also allowing expansion/contraction of the road/pavement surface, due to the compressibility of tar or the like.

Secondly, the joints between sections/edges of roadways, if left unfilled, provide points at which water can enter and migrate beneath the roadway, from which a large number of problems can result. In particular, subterranean water causes potholes and undermining, in addition to possible "blow—ups". These "blow—ups" occur when water trapped beneath the road begins to boil, or freeze, in extreme temperatures, finally resulting in the road surface being lifted.

As a result of the above mentioned problems, road maintenance agencies utilise crews of workers which are provided with tar heating and spraying equipment, conventionally comprising a compressor and a tar kettle drawn by, or mounted to, a truck. Hot tar is used both for the reduced viscosity thereof, and because the heat of the tar ensures that the tar does not solidify in the spraying nozzles, thereby blocking same. However, tar does initially flow when cold, but once exposed to air will rapidly cure, and has thus previously not been used cold in spraying applications, due to the likely blockage of spraying nozzles, etc.

The use of hot tar does however suffer from a number of draw backs. The most obvious problem is the requirement to heat the tar, which adds to the cost of the procedure, but also is a significant hazard due to the reservoir of hot tar which must be maintained, in addition to hot tar being sprayed from one or more nozzles, which obviously poses a safely hazard. In addition, when such hot tar is sprayed onto non horizontal surfaces, in particular vertical surfaces such as kerb sidewalls or the like, the reduced viscosity of the tar, as a result of heating, may result in significant quantities of the tar flowing off the area to be coated, thereby significantly reducing the effectiveness of same.

The present invention has therefore been developed with a View to mitigating the above mentioned problem.

The present invention therefore provides a road repair material dispensing head comprising a body defining a chamber having an inlet through which a road repair material may be supplied to the chamber; a nozzle defined by an aperture in a side wall of the body; and an actuator operable to selectively render the nozzle in fluid communication with the chamber.

Preferably, the nozzle is defined solely by the aperture in the side wall of the body.

Preferably, the chamber has an outlet from which the road repair material may be withdrawn from the chamber.

Preferably, the actuator comprises a gate Valve mounted within the chamber and displaceable between a first position occluding the nozzle from the chamber, and a second position exposing the nozzle to the chamber.

Preferably, the gate valve defines a passage which, when the actuator is in the first position, communicates at a first end with the inlet and at a second end with the outlet, while bypassing the nozzle.

Preferably, when the actuator is in the second position the inlet, the outlet, and the nozzle are each in fluid communication with one another.

Preferably, the gate Valve is pivotably mounted within the chamber.

Preferably, the actuator comprises a handle connected to the gate valve, the handle being located externally of the body.

Preferably, the chamber is cylindrical in form, and the gate valve is a ball valve having an exterior diameter substantially equal to an interior diameter of the chamber.

The present invention will now be described within reference to the accompanying drawings, in which; Figure 1 illustrates a schematic side View of a preferred embodiment of a road repair material dispensing head according to present invention, in which an actuator thereof is in a first position; and Figure 2 illustrates a side elevation of the dispensing head illustrated in Figure 1, in which the actuator is in a second position.

Referring now to the accompanying drawings, there is illustrated a preferred embodiment of a road repair material dispensing head according to the present invention, generally indicated as 10, for use in dispensing/spraying a non heated road repair material such as tar or the like. The dispensing head 10 comprises a body 12 which in the preferred embodiment illustrated is formed from a cylindrical side wall 14 which defines a chamber 16 therein. It will be appreciated however from the following description that the body 12 need not be cylindrical in form, and has been chosen for practical purposes, allowing connection of the dispensing head 10 to conventional hydraulic circuitry (not shown) the like or components such as hoses or (not shown), as will be described hereinafter.

The body 12 is provided with an inlet 18 at one end, and an outlet 20 at an opposed end, with the chamber 16 extending therebetween. Both the inlet 18 and the outlet 20 are internally threaded, in order to allow a supply line or hose (not shown) or equivalent to be connected to the inlet 18, and similarly an exhaust line or hose (not shown) to be connected to the outlet . It will of course be appreciated that both the inlet 18 and outlet 20 could be externally threaded to facilitate connection of the requisite lines (not shown) to the dispensing head 10. In addition, any other suitable means (not shown) may be employed to allow the supply and withdrawal of a road repair material to the dispensing head 10.

It will therefore be appreciated that the provision of the inlet 18 and outlet 20 means that the dispensing head 10 is designed for use in a circuit (not shown) configurated to provide a recirculating tar supply, whereby tar is provided under pressure from a suitable reservoir (not shown), to the dispensing head 10 to be sprayed therefrom while passing through the dispensing head 10, as will be described hereinafter in detail.

The tar does not therefore terminate in the dispensing head 10, and is recirculated back to the tar reservoir (not shown), such that the tar is continually moving or circulating within the circuit or lines (not shown) employed with the dispensing head 10. In this way the non heated tar will not have an opportunity to partially or fully solidify within either the thereby dispensing head 10, or the associated lines, preventing a blockage of the dispensing head 10. This recirculating functionality is particularly important where the dispensing head 10 may be out of use for sustained periods, and it will therefore be appreciated that the outlet 20 could be omitted/occluded, such that the tar supply terminates at the dispensing head 10, if the dispensing head 10 is in substantially constant use.

As mentioned above, the dispensing head 10 is adapted to selectively emit a spray of tar or other road repair material therefrom, and in this regard the dispensing head 10 is provided with a nozzle 22 provided in the side wall 14, and in the preferred embodiment illustrated at approximately half way along the length of the body 12.

As will become apparent from the following description, the dispensing head 10 is adapted to selectively render the nozzle 22 in fluid communication with the chamber , in order to allow a pressurised jet of tar (not shown) or the like to issue from the chamber 16, through the nozzle 22, to be coated onto a surface (not shown) or the like. In this regard, the dispensing head 10 is provided with an actuator 24 which is adapted to selectably expose the nozzle 22 to, or occlude the nozzle 22 from, the chamber 16. In the embodiment illustrated, the actuator 24 comprises a ball valve 26 which is substantially spherical in form, and which is pivotably mounted within the chamber 16 about a longitudinal axis 28 of the ball valve 26. The actuator 24 further comprises a handle 30 connected to the ball valve 26, the handle 30 being located externally of the body 12 in order to be manually engagable and operable.

The ball valve 26 has a diameter substantially equal to the internal diameter of the body 12, such that the ball valve 26 would substantially occlude the chamber 16, were the ball valve 26 solid in form. However, the ball valve 26 is provided with a passage 32 extending completely therethrough, thus defining a pair of walls 34, one on either side of the passage 32. The actuator 24, and in particular the passage 32, is displacable between a first position as illustrated in Figure 1, and a second position as illustrated in Figure 2, by effecting the manual rotation of the handle 30. It will of course be appreciated that the handle 30 could be replaced with any other suitable alternative, and in addition need not be manually operable. For example, a solenoid (not shown) or the like could be utilised to effect the pivotal displacement of the ball valve 26, as could one or more hydraulic or pneumatic rams (not shown) or the like.

In the first position as illustrated in Figure 1, the passage 32 extends in a direction longitudinally of the body 12, and renders the inlet 18 and the outlet 20 in fluid communication with one another, allowing the uninterrupted flow of tar (not shown) or the like through the chamber 16. However, in this first position, it can be seen that one of the walls 34 is disposed adjacent the nozzle 22, thereby occluding the nozzle 22 from the chamber 16, and thus preventing the pressurised tar within the chamber 16 from being sprayed from the nozzle 22. In order to further improve the seal effected between the ball valve 26, and in particular the respective wall 34 thereof, and the nozzle 22, and to provide further support to the ball valve 26, the dispensing head 10 is provided with a pair of shoulders 36, one disposed on either side of the ball valve 26, each being secured to the side wall 14. Each shoulder 36 meshes closely with the ball valve 26, both to support same and to prevent the migration of tar between the ball valve 26 and each shoulder 36. At either end thereof, each shoulder 36 extends away from the side wall 14 into the chamber 16, thereby effectively acting as a baffle directing the tar away from the side wall 14 in the region of the ball valve 26, both to guide the tar through the passage 32, and to direct the tar away from the nozzle 22.

Thus with the actuator 24 in the first position, cold tar enters the chamber 16 via the inlet 18, passes straight through the passage 32, consequently bypassing the nozzle 22, and exits the chamber 16 via the outlet . Therefore when the actuator 24 is in the first position, tar is continually circulated through the dispensing head 10, without being sprayed from the nozzle 22. This continual circulation ensures that the tar does not solidify within the dispensing head 10, causing a blockage.

When it is desired to spray tar from the nozzle 22, the actuator 24 is moved into the second position as illustrated in Figure 2, by means of the manual displacement of the handle 30. In this second position, the chamber 32 extends in a direction diagonally across the chamber 16 such as to be in fluid communication with both the inlet 18, the outlet 20, and the nozzle 22. In this way tar is still capable of circulating through the dispensing head 10, but as the nozzle 22 is exposed to chamber 16, and consequently the pressurised tar flowing therethrough, a spray of tar will issue from the nozzle 22 as the tar passes through the chamber 16. Thus spraying may be effected by the dispensing head 10 by displacing the actuator 24 into the second position, which still however allows the tar to circulate through the dispensing head 10 and associated circuitry (not shown), thereby preventing the tar from clogging either the dispensing head 10 or associated circuitry, as hereinbefore described.

When it is desired to cease spraying, the actuator 24 is simply displaced back into the first position, whereby the nozzle 22 is again occluded by the respective wall 34, while the tar continues to circulate through the dispensing head 10.

Once a spray of tar has issued from the nozzle 22, and the actuator 24 displaced back into the first position, a small amount of tar will remain in the nozzle 22. If the nozzle 22 is not then used for a prolonged period, the tar within the nozzle 22 will solidify, as a result of being exposed to air. Thus when the dispensing head is next used, and an attempt made to spray tar from the nozzle 22, the nozzle 22 will be blocked. For this reason the depth of the nozzle 22 is extremely shallow, with the nozzle 22 essentially being defined by an aperture in the side wall 14, such that the nozzle 22 has a depth substantially equal to the thickness of the side wall 14. As a result any plug of tar (not shown) which solidifies within the nozzle 22 will be very short in length, and will have a relatively small surface area in Contact with the nozzle 22. For this reason when the actuator 24 is displaced into the second position, the pressure of the tar passing through the chamber 16 will be sufficient to immediately dislodge the plug of tar (not shown) from within the nozzle 22, thereby enabling spraying to be effected, regardless of whether or not the dispensing head 10 has been out of use for a prolonged period.

It will be appreciated that the actuator 24, and in particular the ball valve 26, could be replaced with any other suitable equivalent which provides the functionality of the actuator 24 as hereinbefore described. The ball Valve 26 could be replaced with any other suitable valve (not shown) or the like which enables tar to both flow through the dispensing head 10 without issuing from the nozzle 22, and to flow through the dispensing head 10 while also being emitted as a spray from the nozzle 22.

As the dispensing head 10 may be used with a supply of cold tar (not shown), no heating equipment (not shown) and associated componentary is required, thereby greatly reducing the cost and complexity of any apparatus (not shown) with which the dispensing head 10 is to be used, not to mention the improved safety of any such apparatus (not shown). For example, the dispensing head 10 may be used with a hand drawn (not shown) apparatus essentially comprising a reservoir of tar (not shown), the tar through the dispensing head 10 to be sprayed therefrom as required. Such an apparatus (not shown) could simply be mounted on a pair of wheels or the like, and be provided with a handle in order to allow the apparatus to be drawn along a roadway or the like.

Such an apparatus (not shown) could then be manned by single individual, greatly reducing the cost and time taken to effect the coating of various surfaces with tar. In order to achieve a more even application of the tar over a surface, once sprayed thereon, such an apparatus (not shown) could be provided with a brush (not shown) or the like, trailing the dispensing head and lightly contacting the surface, which brush would then spread the tar more evenly over the surface.

The present invention is not limited to the embodiment described therein, which may be amended or modified without departing from the scope of the present invention. and a compressor to pump

Claims (5)

Claims

1. A road repair material dispensing head comprising a body defining a chamber having an inlet through which a road repair material may be supplied to the chamber; a nozzle defined by an aperture in a side wall of the body; and an actuator operable to selectively render the nozzle in fluid communication with the chamber.

2. A road repair material dispensing head according to claim 1 or 2 in which the chamber has an outlet from which the road repair material may be withdrawn from the chamber.

3. A road repair material dispensing head according to any preceding claim in which the actuator comprises a gate valve mounted within the chamber and displaceable between a first position occluding the nozzle from the chamber, and a second position exposing the nozzle to the chamber.

4. A road repair material dispensing head according to claim 3 in which the gate valve defines a passage which, when the actuator is in the first position, communicates at a first end with the inlet and at a second end with the outlet, while bypassing the nozzle.

5. A road repair material dispensing head 14 according to claim 3 or 4 in which, when the actuator is in the second position, the inlet, the outlet, and the nozzle are each in fluid communication with one another.