NZ517418A - Mobile machine for laying compacted particulate material - Google Patents

Abstract

A mobile machine for laying on the ground or other supporting surface a layer of compacted particulate material. In particular, the invention relates to a machine of this type which is capable of laying a layer of compacted particulate material accurately both to a predetermined height and to a predetermined path on the ground.

Description

New Zealand Paient Spedficaiion for Paient Number 517418 NZ Patent Application No. 517418 Filed: 25 February 2002 Patents Form No. 5 Patents Act 1953 COMPLETE SPECIFICATION MOBILE MACHINE FOR LAYING COMPACTED PARTICULATE MATERIAL I, Paul Winston FREER, a New Zealand citizen of 8 Wales Street, Halswell, Christchurch, New Zealand, hereby declare the invention for which I pray that a patent may be granted to me, and the method by which it is to be performed, to be particularly described in and by the following statement 1 Intellectual Property Office, of NZ 21 MAY 2003 The present invention relates to a mobile machine for laying on the ground or other supporting surface a layer of compacted particulate material. In particular, the invention relates to a machine of this type which is capable of laying a layer of compacted particulate material accurately both to a predetermined height and to a 5 predetermined path on the ground.

The machine of the present invention has been developed especially for laying a supporting layer of road metal along the intended track of a road kerb, so that the kerbing can be laid by an automatic kerb forming machine without additional surface 10 preparation; the invention therefore will be described with particular reference to this application. However, it will be appreciated that the machine of the present invention is not limited to this application and could be used for any of a range of applications where a layer of compacted particulate material needs to be laid to an accurate height on a precise predetermined path on the ground.

To lay a length of kerbing along the side of a road, the level of the road bed must be built up over the track along which the kerbing will be laid, to support the kerbing. The kerbing usually is laid by an automatic kerb forming machine. Generally, the built up supporting area needs to be about 115 mm wide and about 65 mm high. Further, the 20 built up supporting area must extend right up to the edge of where the completed kerbing will lie, and must follow the intended track of the completed kerbing very accurately.

At present, the kerbing support layer is built up by hand, with the road metal shoveled 25 into place and compacted with hand-held compactors, following the string line which has been laid to guide the kerbing machine. This process is very time-consuming and therefore expensive, and also is not very accurate:- typically, the height of the built up layer may vary by as much as 35 mm.

It is therefore an object of the present invention can provide a machine capable of forming the kerbing support layer rapidly and accurately.

The present invention provides a mobile machine for laying compacted particulate material such as road bed, said machine comprising:- a hopper adapted to hold a supply of particulate material and to deposit a stream of 10 particulate material upon the ground or other supporting surface beneath the machine; driven rotatable compaction means supported adjacent the hopper and adapted to provide a first initial compaction to said deposited particulate material; a vibrating plate having a width substantially equal to that of the desired final width of the compacted particulate material and supported at a height above the ground substantially equal to the desired final height of the compacted particulate material; said vibrating plate being supported downstream from the driven rotatable compaction 20 means in the direction of travel of the machine in use, so as to provide the final compaction for the particulate material.

Preferably, a spring-loaded bar is mounted between said driven rotatable compaction means and said vibrating plate, for additional compaction of the particulate material.

Preferably, the driven rotatable compaction means comprises a hexagonal roller. 3 Preferably also, the width of the vibrating plate is greater than the width of the rest of the machine so that at least one side of the machine the vibrating plate protrudes from the side of the machine.

By way of example only, a preferred embodiment of the present invention is described in detail with reference to the accompanying drawings, in which:- Fig. 1 is a diagrammatic side view of a machine in accordance with the present invention; Fig. 2 is a diagrammatic longitudinal section through part of Fig. 1, on enlarged scale, showing the sequence involved in the deposition of the road metal; and Fig. 3 is a diagrammatic longitudinal section through part of Fig. 1, showing part of the 15 apparatus of Fig. 2 but on a greatly enlarged scale.

Referring to Fig. 1, a machine 2 in accordance with the present invention comprises a chassis 3 (parts of which are omitted for clarity) which is supported from the ground by a pair of front wheels 4, and 5 driven rear wheels arranged as a set of three wheels 5 20 on a common axis and a pair of wheels 6. Both the front and rear wheels are steerable.

In the embodiment shown in Fig. 1, the machine is steered manually by means of a steering wheel 7 which is connected to the front wheels by steering linkages of known 25 type. However, the machine also may be computer-controlled and arranged to be steered by means of a laser sight. 4 The central portion of the machine 2 is supported upon the wheels 4,5,6 by two pairs of hydraulic jacks 8,9; the jacks of each pair are spaced apart across the width of the machine. Each of the front jacks 8 is independently controllable, and the rear jacks 9 can be adjusted as a pair, independently of the jacks 8, so that both the height of the 5 central portion of the machine above the ground and the angle of tilt of the central portion can be adjusted by the operator of the machine, to compensate for any variations in the angle of the road bed upon which the built up portion is to be placed. A set of bubble levels (not visible) is mounted adjacent the steering wheel 7 to allow the operator to gauge the angle of the machine.

For additional control of the tilt of the machine, a further horizontal jack (not shown) may be mounted across the width of the machine adjacent the rear wheels.

A motor (shown diagrammatically at reference numeral 10) is mounted on the chassis 15 3 and drives a hydraulic pump (not shown) which provides the power for the movement and control of all the components of the machine, including an hydraulic drive 11 to the rear wheels 5,6, and power for the steering system to the front wheels 4. The control system for the hydraulic drive 11 to the rear wheels 5,6 includes an hydraulic clutch, so that the hydraulic drive can be set to a constant speed, and the 20 machine stopped and started by the operator using the hydraulic clutch. This ensures that the machine moves at a steady, uniform pace.

It will be appreciated that alternative drive and control systems may be substituted if desired.

Road metal to be laid by the machine is stored in a hopper 12; the hopper could be filled manually but normally would be filled by a mechanical device e.g. front-end loader. The base of the hopper 12 is open across the full width of the machine, allowing a continuous stream of road metal to fall from the base of the hopper onto the ground underneath the machine. A flanged roller 13 is mounted a short distance above the base of the hopper 12, parallel to the opening in the base. The roller 13 can be rotated either continuously or intermittently by means of a drive belt 14 and pulley 15 5 from a driven pulley 16, to prevent bridging of the road metal in the hopper.

As shown on a larger scale in Fig.s 2 and 3, road metal deposited from the base of the hopper 12 is compacted initially by a rotating hexagonal roller 17 which extends across the full width of the machine and which is driven to rotate in direction of arrow A in Fig. 10 3 i.e. anticlockwise. The rotation of the roller 17 smoothes, levels and compacts the road metal.

A spring-loaded bar 20 is mounted below and slightly to the rear of the roller 17 in the direction of travel of the machine (arrow M). The bar 20 extends the full width of the 15 machine, and comprises a substantially vertical portion 24 with a substantially horizontal portion 23 extending from the portion 24 a short distance from the lower end of the portion 24. The lower edge 22 of the portion 24 acts as a leveling bar in use, and lies in the same horizontal plane as the lowermost face 18 of the roller 17. The portion 23 overlaps the lower limb of a U-shaped supporting bracket 21.

The bar 20 can move in a substantially vertical plane (arrow B) and is spring biased towards the position shown in Fig. 3 by means of a coil spring 25 mounted between the side portion 23 and the upper limb of the supporting bracket 21. The bar 20 also can move in a substantially horizontal plane (arrow C) and is spring biased to the position shown in Fig. 3 by a second coil spring 26 mounted between the vertical limb 25 of the supporting bracket 21 and the parallel face of the portion 24.

Immediately to the rear of the bar 20 in the direction of travel of the machine is a 6 sloping plate 27 which extends across the full width of the machine and provides a smooth lead in below the edge 28 of a vibrating plate 30.

The vibrating plate 30 provides the final compaction for the road metal. The plate 30 is 5 formed with a smooth flat lower surface which in use contacts the road metal; the opposing side edges of the plate 30 are formed with vertical edges 32 which prevent the road metal being compacted from moving out to either side of the plate, and leave the final compacted road metal surface with a clean edge along each side.

The width of the plate 30 is such that the plate extends across and slightly beyond the full width of the machine. Because the plate is wider than the rest of the machine, one outer edge of the plate can extend right up to the string line which marks the position of the kerbing, without the machine's wheels fouling the string line.

The vibrating plate 30 is flexibly supported from the chassis such that it is free to vibrate but can be raised and lowered with the chassis, so that the height above the ground of the lower surface of the plate can be very accurately adjusted. The plate 30 is vibrated by means of a vibrating motor (not shown) of known type which is mounted on the upper surface 34 of the plate 30. Operation of the vibrating motor vibrates the plate 30 in a substantially vertical plane.

The machine includes a water tank 36 from which water may be pumped to a spray bar 37 which extends across the width of the machine just in front of the leading edge 28 of the vibrating plate 30.

The above described machine is operated as follows:- road metal is loaded into the hopper 12 using a loader or similar device. The type of road metal used depends 7 upon the requirements of the kerbing contractor, but typically would be pre-graded road metal of the type used for the top course of a road e.g.M4-40.

The motor 10 of the machine is started to power the hydraulic pump and hydraulic 5 drive. The operator adjusts the height of the machine, using the hydraulic jacks 8,9, until the height of the inner surface of the vibrating plate 30 above the road bed is correct for the desired final height of the kerbing buildup. The jacks may also be used to ensure that the plate 30 is level. The speed of the machine is set to the desired forward speed (typically about 3.5 - 4 m per minute), and the operator uses the 10 steering wheel 7 to guide the machine such that one outer vertical edge 32 of the plate 30 is aligned with the string line which has been erected to guide the kerb laying machine.

As the machine moves forward, road metal is deposited from the hopper 12 onto the 15 road surface and is smoothed and initially compacted by the hexagonal roller 17. The compacted road metal next is smoothed by the spring-loaded bar 20. In the event that larger stones jam between the roller 17 and the bar 20, or between the bar 20 and the road surface, the spring loading of the bar 20 by the springs 25 and 26 enables the bar 20 to release the jam.

As the machine continues to move forward, the compacted road metal slides under the plate 27, below the leading edge 28 of the vibrating plate 30 and is finally compacts at to the required final height by the vibration of the plate.

The water spray from the spray bar 37 assists in the compaction of the road metal and helps to reduce dust. 8

Claims (1)

1. It has been found that the machine of the present invention is capable of producing a built-up surface for a kerbing machine to a tolerance of +/-3 mm:- an order of magnitude more accurate than that achieved with manual construction, and very much faster. Since the built-up surface produced by the machine of the present invention 5 extend right up to the kerbing string line, an automatic kerb forming machine can follow straight after the machine of the present invention to lay the kerbing, without any other preparatory work being required. It is possible to construct the machine without the bar 20, if the rate of forward 10 movement of the machine is relatively slow and/or if the rate of deposition of particulate material is low. 9 A mobile machine for laying compacted particulate material, said machine including:- a hopper adapted to hold a supply of particulate material and to deposit a stream of particulate material upon the ground or other supporting surface beneath the machine; driven rotatable compaction means supported adjacent the hopper and adapted to provide a first initial compaction to said deposited particulate material; a vibrating plate having a width substantially equal to that of the desired final width of the compacted particulate material and supported at a height above the ground substantially equal to the desired final height of the compacted particulate material; said vibrating plate being supported downstream from the driven rotatable compaction means in the direction of travel of the machine in use, so as to provide the final compaction for the particulate material. The machine as claimed in claim 1, wherein the width of the vibrating plate is greater than the width of the rest of the machine, such that at at least one side of the machine, the vibrating plate protrudes from the side of the machine. The machine as claimed in claim 1 or 2 wherein said vibrating plate is formed with substantially vertical side edges. The machine as claimed in any one of the preceding claims further including an inclined plate which is arranged to extend across the full width of the vibrating plate upstream of the vibrating plate and is inclined at an obtuse angle to the vibrating plate, with the edge of the inclined plate closest to the vibrating plate terminating adjacent and at substantially the same level as the vibrating plate, so as to provide a smooth lead in to the vibrating plate. The machine as claimed in any one of the preceding claims, further including a 10 springloaded bar mounted between said driven rotatable compaction means and said vibrating plate, said bar being adapted to provide additional compaction of the particulate material. 5 6. The machine as claimed in claim 5 wherein said springloaded bar is capable of movement in both the vertical and the horizontal planes against the bias of the springs. 7. The machine as claimed in any one of the preceding claims wherein the driven 10 rotatable compaction means comprises a hexagonal cross-section roller. 8. The machine as claimed in any one of the preceding claims wherein the hopper contains an agitator. 15 9. The machine as claimed in any one of the preceding claims wherein the hopper opens across the full width of the machine. 10. The machine as claimed in any one of the preceding claims, further including front and rear jacks adapted to provide adjustment of the height of the driven 20 rotatable compaction means and the vibrating plate above the ground. 11. A mobile machine for laying compacted particulate material, substantially as hereinbefore described with reference to and as shown in the drawings accompanying the provisional specification. 11