GB2308149A - Apparatus for laying a surface - Google Patents

Description

APPARATUS FOR LAYING A SURFACE The invention relates to apparatus for laying a surface, particularly a sand andi or activated carbon layer of a slow sand filter for use in filtering water in a water treatment works.

Such apparatus has to be laid to a good degree of horizontal tolerance with an upper surface which is essentially screeded. Screeding machines are known, but they are extremely expensive and in any event are not suitable for use in a slow sand filter as they are heavy, and thus liable to disrupt the surface being laid, and they are not flexible in the sense that they can only screed "strips" substantially equal to the width of the machine.

It is an object of the invention to seek to mitigate these disadvantages.

According to the invention there is provided apparatus for use during laying a surface, comprising a vehicle having a part which is slewable with respect to the rest of the vehicle, and a working head which is rotatable through an arc relative to the slewable part.

The working head may comprise a plough-like blade. This provides for ease of use and application, particularly where there may be a single blade.

The vehicle may comprise a base part with means for movement of the vehicle over a surface and the slewable part may comprise an upper body part of the vehicle. This provides for a controllable apparatus.

The upper part may comprise an arm on the remote end of which may be mounted the plough-like blade. Alternatively, the slewable part of the vehicle may comprise an arm per se which may carry the plough-like blade. Either construction can provide for a wide area of application, particularly where the arm is extensible.

The arm may be rotatable in a direction about its longitudinal axis. This provides for control of the blade in use.

There may be means to rotate the plough-like blade relative to the length of the arm. This provides for substantial universal application.

The means may be operative to rotate the plough-like blade about a substantially vertical axis. This provides for control in a substantially horizontal plane.

There may be a hydraulic system of the vehicle for controlling slewing and/or rotation of the plough-like blade.

There may be means adapted to monitor the height of the working head. This provides for depth control.

The means may comprise a laser means.

The slewable part of the vehicle may be capable of slewing through substantially 3600.

The vehicle may be any suitable vehicle such as a tracked vehicle, a wheeled vehicle, a semi-track vehicle or a vehicle similar to a backhoe loader or digger, where the bucket is replaced by the plough-like blade.

The plough-like blade may comprise a cutting blade.

The cutting blade may be adjustable in height with respect to the plough-like blade.

There may be means to adjust the height of a working edge of the plough-like blade, in which the means may comprise a hydraulic cylinder arrangement. This is a relatively simple means.

Apparatus for laying a surface embodying the invention is hereinafter described, by way of example, with reference to the accompanying drawings.

Fig. 1 shows a schematic view of part of the apparatus in use during laying of sand and granulated activated carbon layers in a slow sand filter; Fig. 2 shows the apparatus of Fig. 1 to a larger scale; Fig. 3 shows schematically a side elevational view of a modified working head of the apparatus; Fig. 4 shows a side elevational view of a further modified working head of the apparatus; and Fig. 5 shows schematically a vehicle according to the invention.

Referring to the drawings there is shown apparatus 1 for use during laying a surface 2, such as a sand and/or granulated activated carbon layer of a slow sand filter. The apparatus 1 comprises a vehicle 3, in the embodiment a tracked vehicle, having a part 4 slewable with respect to the rest 5 of the vehicle, and a working head 6 which is rotatable or swingable through an arc relative to the slewable part 4.

The vehicle 1 has an upper body part including a cab 7 for an operator, comprising the slewable part 4, and which has an arm or boom 8 which is extensible towards or away from the vehicle, which can be rotatable about a main or longitudinal axis and which carries at its end remote from the slewable part 4 the working head 6 which is in the form of a single plough-like blade 9 in the embodiment.

The slewable part 4 may be slewable with respect to the remainder of the vehicle, a tracked part or base 5, through substantially 360 , though slewing can be restricted to less than 360".

There is a suitable power means such as a hydraulic system (not shown) which is operative to rotate the working head 6 in a substantially horizontal plane, in other words about an axis 'X' which is substantially vertical as viewed in the Figs.

During use in laying a sand or carbon surface, the apparatus 1 is used to skim sand or carbon, level sand or carbon, and/or lay or spread sand and/or carbon.

This is achieved by "parking" the vehicle 1 in a desired position, extending the arm 8, and then providing prime movement to the head 6 by slewing the slewable part 4, the working head 6 being rotated about the axis 'X' so that its lower (as viewed) working or cutting edge 10 can "work" the surface 2 so that the surface has the desired degree of "levelness" and the layer the desired thickness.

Control of the "height" of the cutting edge 10 is achieved and monitored using a laser levelling system which can be a receiver 11 on an arm 12, which provides laser signals via a laser transmitter at a datum for example on the side of the slow sand filter. The transmitter can be a standard transmitter, or a dual plane transmitter. Such a dual plane laser transmitter offers the opportunity of laying a concrete screed, or other material which is liable to "slump" to a predetermined angle and slope. The laser system provides a signal in the cab 7 which the operator driving the vehicle 3 can monitor and therefore make necessary adjustments in height and swivelling of the blade 9 and slewing of the slewable part 4 of the vehicle.

In the case where there is a requirement for a fine control of the cutting edge 10, for example for precision skimming of a surface, the embodiment of Fig. 4 can be used. In this embodiment the blade 9, and hence its cutting edge, is controlled height-wise by an additional hydraulic piston and cylinder arrangement 13.

This is serviced by the same hydraulic system lines as used for rotation of the working head for example a solenoid operated valve (not shown), mounted on the working head can be used to change modes, that is into or out of the "fine control mode". The operator would operate a toggle switch from the cab, thus sending 1 2v (or 24v) signal, via cable, to the solenoid.

In this system rotation less than 3600 is envisaged, so as to avoid fouling or cutting of hydraulic and/or electric power lines.

In the embodiment of Fig. 3, there is an additional cutting blade 14 which extends the full width of the plough-like blade 9. The blade 14 may be fixed, or adjustable in height in relating to the plough-like blade 9. Also, this blade 14 could be substituted by teeth extending over the width of the plough-like blade 9. In either case, a predetermined portion of "spoil" encountered during laying a surface, at the front blade 14 or teeth, will pass below the plough-like blade's 9 cutting edge 10.

In a further embodiment, not shown, the whole arm 8 may be the slewable part, there being a hydraulic or other suitable means for slewing the arm, carrying the plough-like blade, relative to the vehicle. The arm may be traversable on a frame laterally across the vehicle to a desired position.

The vehicle may be a wheeled vehicle, which would provide a safe means of laying and removing shingle from filter beds as such a vehicle would be unlikely to damage vulnerable under drains. The plough-like blade may have a resilient tower edge 10 strip. This facilitates shingle removal.

It will be understood that in all embodiments, by slewing the upper part 4 of the vehicle 3, the apparatus 1 can be moved in a large arc under fine control, either using manual or laser guidance. The plough-like blade provides for skimming sand, levelling sand and laying and spreading granulated activated carbon, and acts to both compact and lay these layers.

The apparatus 1 shown in and described with reference to the drawings can: (a) be used to screed concrete; (b) be used for clearing weed within slow sand filter beds by incorporating teeth as mentioned hereinbefore; (c) be used to "windrow" dirty sand in a filter bed that is either fully or partially drained of water, using the plough-like blade. This is useful in certain climates where filter beds are put back into service with a proportion of "dirt"/bacteria remaining within the top layer of media. This allows the bed to function at high capacity soon after going back into service.

Claims (19)

1. Apparatus for use during laying a surface, comprising a vehicle having a part which is slewable with respect to the rest of the vehicle, and a working head which is rotatable through an arc relative to the slewable part.

2. Apparatus according to Claim 1, the working head comprising a ploughlike blade

3. Apparatus according to Claim 2, there being a single blade.

4. Apparatus according to Claim 3, the vehicle comprising a base part with means for movement of the vehicle over a surface and the slewable part comprising an upper body part of the vehicle.

5. Apparatus according to Claim 4, the upper body part comprising an arm on the remote end of which is mounted the plough-like blade.

6. Apparatus according to Claim 5, the arm being extensible.

7. Apparatus according to Claim 6, the arm being rotatable in a direction about its longitudinal axis.

8. Apparatus according to Claim 6 or Claim 7, there being means to rotate the plough-like blade relative to the length of the arm.

9. Apparatus according to Claim 8, the means being operative to rotate the plough-like blade about a substantially vertical axis.

10. Apparatus according to any of Claims 3 to 9, comprising a hydraulic system of the vehicle for controlling slewing and/or rotation of the plough-like blade.

11. Apparatus according to any preceding claim, comprising means adapted to monitor the height of the working head.

12. Apparatus according to Claim 11, the means comprising a laser means.

13. Apparatus according to any preceding claim, the slewable part of the vehicle being capable of slewing through substantially 360".

14. Apparatus according to any preceding claim, the vehicle being a tracked, semi-tracked, or wheeled, vehicle.

15. Apparatus according to any of Claims 3 to 14, the plough-like blade comprising a cutting blade.

16. Apparatus according to Claim 15, the cutting blade being adjustable in height with respect to the plough-like blade.

17. Apparatus according to any of Claims 3 to 16, comprising means to adjust the height of a working edge of the plough-like blade.

18. Apparatus according to any of Claims 3 to 16, the means comprising a hydraulic cylinder.

19. Apparatus for laying a surface substantially as hereinbefore described, with reference to the accompanying drawings.