IMPROVEMENTS RELATING TO ROAD WORKING APPARATUS

Abstract: The road working apparatus (10) comprises a planing drum (22) having picks which break up and remove the road surface as the drum (22) is power driven. The drum (22) is in a hood (26) or casing which has a skirt (46) which locates in relation to the ground surface so that air is drawn into the hood (26) at a controlled rate to maintain the desired flow of air through the hood (26) to ensure the effective removal of the spoil produced. The skirt (46) includes pivotable skid plates at each side of the drum, which skids are independently pivotable so as to fall automatically onto the road surface, cut or uncut, to maintain said air flow automatically.

Description: Improvements Relating to Road Working Apparatus This invention relates to road working apparatus, especially road planers being machines for planing the surface of a road, highway, motorway or the like in order to remove the top surface thereof, for the purpose of road repairs, trench excavation or underground pipe and cable installation or repair. Road planers typically have road planing drums which rotate about an axis which is horizontal when the planer is in use, and the drums have picks or cutting teeth on the surface thereof which break up and plane away the road surface. The planer drums are usually adjustable as to depth in relation to support wheels or the like so that cuts of differing depths may be made, or the planer drum may be used progressively to remove the road surface in a number of passes. Planers may alternatively have vertical axis planer discs. Planers can come in a variety of sizes from large, custom built and self propelled units to small hand operated attachments for general purpose vehicles. The present invention is particularly although not exclusively directed to the smaller type of planer unit, and specifically is particularly applicable to a planer arrangement which is self propelled and operator controlled. Such an arrangement can also be mounted on a vehicle. When a planer is in use, the chippings' and spoil created by the cutting of the road surface have to be disposed of, and although some planing arrangements are provided with an auxiliary suction pipe having an inlet adjacent the working area of the planer, generally, the planings are left on the road surface and subsequently have to be removed by a sweeping apparatus such as a bucket brush or more usually have to be removed by hand or belt conveyor. The present invention is concerned with the removal of the chippings and spoil which arise as a result of the planing operation, and in accordance with the invention in its most general aspect, a planing apparatus comprises at least one rotary planing drum or disc which is contained inside a suction hood or casing, the suction hood having a skirt which is positionable in relation to the road surface to provide for optimum suction when the interior of the hood is subjected to negative pressure for the removal of the spoil by such suction during the cutting operation. In one arrangement, the lower edge of the skirt is provided with a series of notches which define suction apertures, the skirt otherwise engaging the road surface. As an alternative, the skirt may be adjustable in position in relation to the road surface so as to provide an optimum clearance gap. In either arrangement, the skirt may be in a number of independently movable sections, so that if, as a result of previous cutting, one side of the road surface is lower than another, the respective skirt portions can be located at different heights so as to define an even sized suction gap around the skirt periphery. The hood may be constructed of any suitable material, but in view of the need for the hood to perform in conditions where it will be subjected to heavy loading, and vibration, it is preferred that it be constructed of a relatively rigid material such as strong rigid plastics material or sheet metal. In a further aspect of the invention there is provided planing apparatus comprising a rotary planing drum or disc contained inside a suction hood and wherein said cutting depth of the drum or disc in relation to the road surface is adjustable independently from the position of the suction hood. Adjustment of the planing drum or disc may be by moving the drum or disc on a frame which is pivotable or slidable relative to the remainder of the apparatus, in order to effect said adjustment. In a preferred arrangement, when a planing drum is used, the hood is constructed with the skirt in two shaped sections respectively making up a rectilinear sectioned hood. When a disc is used, the hood may be circular. The hood may be connected to a suction pipe which extends from the planing head to a spoil collecting receptacle, and a suitable suction pump will be provided for withdrawing the chippings and spoil. The collecting receptacle preferably is on an accompanying vehicle and the suction pipe extends from the planing head over or alongside the vehicle cabin to the collecting receptacle, suitably positioned on the vehicle hood platform. Embodiments of the present invention will now be described, by way of example, with reference to the accompanying diagrammatic drawings, wherein:- Fig. 1 is a side view showing a vehicle with a planer attached thereto; Fig. 2 is a plan view showing how the planer of Fig. 1 may be used in one example of planing a road surface; Fig. 3 is an enlarged side view showing the planing drum and suction hood thereof; Fig. 4 shows a modification of the planing drum in sectional elevation; Fig. 5 is a view similar to Fig. 1 but showing another embodiment; Fig. 6 is a side elevation of the planer of Fig. 5; and Fig. 7 is a sectional end elevation of the planer of Fig. 6. Referring firstly to Fig. 1, a conventional suction sweeper vehicle in the form of a wagon is indicated by reference 10, and it comprises a conventional cabin 12 and load platform 14. To the front of the cabin 12 is a mounting 16 by which a planer machine 18 is carried by a cantilever arm structure 20. The planing machine 18 comprises planing drum 22 arranged with its axis of rotation 24 horizontal, and the drum 22 is contained in suction hood 26 to which is connected a suction pipe or hose 28 extending from hood 26 over the cabin 12 and to a suction box 30 of the sweeper vehicle and which is in use vacated by means of a fan 32 to create a suction box which in turn creates the suction in the hood 26 so that loose chippings and cuttings generated by the rotation of the drum 22 are induced directly into the collection box 30. The hose 28 may be provided with appropriate swivel couplings 34, 36, to enable the planing machine 18 to be manipulated without causing any undue stress on the flexible hose. The planing machine 18 can be manipulated for example by means of manually operated handle 38 over a substantial area of the road surface 40 to remove the top layer thereof, and the machine 18 is provided with support wheels 42, 44 which also form depth control wheels. The drum 22 is adapted to be independently moved vertically relative to the wheels 42, 44 to enable cuts of different depths to be made. During cutting the practice would be to lift the cutter clear of the ground to a raised travel position whilst leaving the suction hood set at its pre-determined air gaps for a few seconds after the cutting sequence is finished so that the area is completely cleaned before the machine moves away. In a modified arrangement the arm 20 is omitted and the planer can move relatively freely theonly connection to the planer being by the hose 28. Also, with this arrangement, the planer can operate behind the sweeper vehicle. The hood 26 is arranged as shown in Fig. 3 so that it has a skirt 46 which is located at a predetermined clearance 48 relative to the road surface 40 so that the correct suction gap is established to ensure that the spoil and chippings are effectively conveyed from the suction head 26 to the hose 28 and thence to the box 30. Arrows 50 indicate the passage of the chippings and spoil and arrow 51 indicates the direction of rotation of the drum 22. In Fig. 3, the line 52 indicates the adjustability of the drum 22 which is adapted to be pivoted around the axis 54 of the wheel 44. Alternatively, it may be mounted for linear adjustment on a vertical slide. The control of the suction gap between the road surface and the skirt 46 is important to the effective functioning of the apparatus 18. The drum 22 is located inside the hood 18 which is a novel approach for this type of machine, but desirably the gap 48 is accurately maintained. Therefore, when, as shown in Fig. 2, cutting takes place in a number of parallel strips 56, 58, 60 and 62, when the cutter drum 22 is making a cut, the road surface may be lower at one side than at the other side (the uncut side) and therefore it is of advantage as shown in Fig. 2 to make the skirt 46 in two or more adjustable in height sections so that the respective sections can be arranged at different levels thereby to maintain the said clearance 48. In the arrangement of Fig. 2, the skirt 46 is in two sections 46A and 46B each of right-angled configuration as shown, the section 46B in the configuration shown in Fig. 2 being arranged at a lower level than the section 46A due to the fact that the cuts 60 and 62 represent ground surface at a lower level than the surface 40. When the drum is replaced by a disc, the hood may be of an alternative configuration, for example it may be circular or elliptical as required. Fig. 2 also shows that additional stabilizing wheels 44A, 44B may be provided as required. Fig. 3 also shows an alternative configuration for the lower edge of the skirt 46 in that the said lower edge is provided with air inlet gaps 64 so that in fact the lower edges of the skirt 46 or skirt portions lie on the road surface as cutting is taking place, the suction air being drawn into the designed gaps 64. These gaps are arranged to give the most effective suction performance. If there is too much clearance between the lower edge of the skirt and the ground surface, then the suction effect is lost, and the same applies if there is too little of such clearance, although in the modification of Fig 4 the skirt portion at one side of the drum is omitted to enlarge the suction effect. In this case the shorter leg of short portion 46B is omitted leaving that side 100 of the hood open to enable air to be drawn towards the drum surface when it travels into the channel. The drum is provided with radial bars or blades 102 or vanes arranged in appropriate configuration and not necessarily behind the rows of cutting picks 104 (as shown) to create an air flow gap 106 in conjunction with the ground to induce the suction to transport the debris efficiently to the outlet of hood 26. The front of the hood skirt is provided with a rubber seal strip 108 and the sides may be provided with similar strips or skirt plates as described in relation to Figs. 5 to 7. In a modified arrangement the cutter is a disc which has carbide tipped cutting picks which is rotatable about a vertical axis defined by its shaft. The hood is circular and has a suction hose. This planer operates in the smae principle as that described in relation to the other figures in that the picks cut through the blacktop surface, and into the ground below. In one configuration, the carbide tipped picks are attached to an earth auger type head forming disc so that when the cutter penetrates the blacktop surface it continues to excavate the sub-base and soil down to the depth of the service to be repaired or installed. The cutter is contained within the suction hood and an air gap is arranged between the skirt of the hood and the road surface. Again, the depth of operation of the cutter and the air gap are independent. The hood may be lifted by one mechanism and the cutter shaft by an independent lift mechanism. The ground clearance between the rubber skirt attached to the hood and the highway is maintained by a stop, or series of stops peripherally of the hood. This arrangement is suitable for repairs of underground services. Referring now to Figs. 5, 6, 7 of the drawings, another form of planer is indicated by numeral 10X, and it will be seen to comprise a unit which is mounted on a sweeper vehicle 12X which is of a conventional construction. The vehicle 12X has a cuttings collection body 11X which can be tipped as shown to discharge its contents. The vehicle has a suction hose 13X which normally is used by an operator for picking up leaves and other debris on the road surface, but in this adaptation the hose is connected to the planer 10X in the same manner as shown in Fig. 1 only in this case the hose 13X extends past the driver's hole of the vehicle cab. The planer 10X is mounted on the front of the vehicle 12X on the normally provided DIN plate and is movable up and down thereon so that the planer 10X can be jacked down onto the road in fact to lift the front end of the vehicle to transfer its weight onto theplaner 10X. Because of this arrangement the planer 10X has a creep speed drive wheel 18X for moving the entire equipment forward during planing. Variations of the arrangements are possible. Thus, the vehicle could be provided with one or more creep speed wheels (front/rear) if it does not already have a creep speed facility (some sweepers and other vehicles do have this facility) in which case the planer need not have a creep speed drive. Also, the planer when it has a creep speed drive need not be connected to the vehicle other than perhaps by the hose 13X and so that it can work all round the vehicle. The vehicle need not be a sweeper vehicle, but preferably will be provided with suction means to withdraw the spoil from the planer. The planer may be provided with its own suction means and collection hopper. Referring now to Figs. 6 and 7, the planer 10X comprises supporting the creep speed traction wheel 18 and the cutting or planing drum 2OX. The planing drum 2OX is surrounded by and connected to a hood 22X which is mounted for pivotal movement about horizontal pivot 24X, the hood being supported and movable by an adjustment ram 26X, the extension and contraction of which swings the hood 22X and the drum 2OX about axis 24X thereby to lower the drum 2OX into the surface of the ground 28X for effecting planing, or for removing same from the ground and into the frame 24X for transportation. The planer includes hydraulic motors 19X, 2IX respectively for rotating the traction wheel 18X, and for rotating the cutter drum 20X. Traction wheel 18X can be driven in forwards or reverse direction at very slow or "creep" speed to enable the unit to be manipulated at a slow and effective rate. It should be borne in mind that very slow speeds are required for the effective planing or cutting away of the road surface 28X. The unit 10X is in fact supported on three wheels namely the traction wheel 18X, a castor wheel 3OX and a depth control and support wheel 32X. Looked at in side view as shown in Fig. 6, the castor wheel 30X trails the traction wheel 18X, it being understood that the unit 10 will move in the direction 34X, and the wheel 32X trails the castor wheel 30X, the drum being arranged with its axis of rotation in side view between the wheels 30X and 32X. In the direction of travel 34X, the traction wheel 18X is in substantial alignment with the cutter drum 2OX, and the wheel 30X is in substantial alignment with the wheel 32X. Wheel 18X may be a steerable wheel in that it is mounted on a king pin 36X, but steering of this wheel is only normally required when the planer is manually manipulable. When it is manually controllable, the unit is particularly flexible, because it has a one piece frame body 14X making it a compact unit, and can be guided around for example man holes and the like. To the front of the hood 22X is provided a sealing blade 4OX of rubber or the like which engages the ground 28X, and which as the unit moves in the direction of arrow 34X flexes to maintain the sealing engagement with the ground. Applied to the hood 22X is a suction so that the spoil created by the drum 2OX as it cuts the road surface, the drum incidentally being rotated in the direction of arrow 42X to perform its cutting, so that such spoil and debris will be effectively drawn away from the cutting region. The cutting drum is of a construction already described herein. As explained herein, control of the suction gap around the cutting drum is important, and in the apparatus as shown in Figs. 6 and 7 of the drawings, this control is effected by the use of side skirt plates 44X and 46X (see Fig. 7). Each skirt plate 44X is hinged relative to the hood 22X about the axis 24X so that as shown in Fig. 7, the skirt plate can fall into engagement with the ground 28X to prevent too large gaps from being created at the side of the unit thereby controlling the suction effect. Air can only therefore be basically be sucked into the hood as indicated by arrow 48X in Fig. 6, at the rear end of the hood, and having regard to the direction of rotation of the drum 2OX, so the air will be sucked into the hood in the direction of rotation of the drum, and then will be drawn upwardly of the hood into an exit pipe 13X to which the suction is applied as indicated by arrow 52X. The means for applying the suction is provided by vehicle 12X but in a portable hood provided with its own engine the engine will drive the suction means and the hood may be arranged to discharge into a separate container or into a hopper formed in the unit 10X as appropriate. The hood plates 44X and 46X may be of flexible rubber-like material or equivalent, although they should be sufficiently robust to withstand wear and tear over a reasonable period. The lower edges 54X and 56X of the plates 44X and 46X may be of the appropriate profile having regard to the groove being cut by the drum 2OX in order to provide the most effective sealing arrangement around the cutting drum for the most effective suction. It should be borne in mind, as shown in Fig. 7 that as the unit 10X performs the road cutting operation, it is likely that it will be in a position as shown in Fig. 7, wherein the cutting drum 2OX whilst cutting a strip of surface material, is in a position where at one side of the drum there will be an already cut region 58X, and the wheels 18X, 30X and 32X will be resting on uncut regions of the road surface. This means that the plate 44X will drop downwardly to a displaced position relative to plate 46X and will rest on a previously cut portion of the surface 28X whereas the plate 46X will be higher and will rest on the uncut road surface. To this end, and to enable the raising and lowering of the plates 44X and 46X, the plates are provided with guide slots 62X of arcuate configuration having their centres of curvature on axis 24X. It will be seen therefore that the plates 44X and 46X can rise and fall freely at least over the extent of the length of the curve slot 62X. Also, the inner plate of the body 14X is provided with a guide slot 64 which receives the shaft 68X of the planer 20X and as shown in Fig. 7, at the end of shaft 68X there is provided the hydraulic motor 2IX which serves the purpose of rotating the planer 2OX as described hereinbefore. Shaft 68X is received in slot 64 so that the shaft can move therein to the extent dictated by the length of the slots 64X, such slot again being arcuate and having its centre on the axis 24X. This means that the planer drum 2OX can be adjusted in height relative to the body 14X and when it is raised so that the shaft 68 is at the top of the slot 64X, the drum will be retracted clear of the ground for transportation. By raising the planer hood 22X and the drum 20X, so the plates 44X and 46X will also eventually be raised. The power for the variou parts of the apparatus is derived in the example illustrated from the engine of the vehicle 12X which is arranged to drive a hydraulic pump which is hydraulically coupled to the apparatus 10X. The controls for the power driven parts of apparatus 10X are housed in the vehicle cabin to be operated by the driver. When the unit is manually controller it may have a tiller handle control by which the motor 18X can be driven in forwards or reverse direction at the selection of the operator, and the control handle operates on the "deadman" principle insofar as if the handle is released, it will return to a neutral position in which the unit stops. The apparatus according to the invention provides an effective means for the removal of the chippings and spoil directly from the planing apparatus to the collection box of a sweeper vehicle. The body of the vehicle may be a tipper body so that the spoil can be tipped at any convenient location. The vehicle may be provided with one or more creep speed wheels (if necessary) the purpose of which is to enable the entire equipment shown in Fig. 1 or Fig. 5 to be moved forwards or rearwards at a slow or "creep" speed. The creep speed wheel or wheels is or are adapted to be jacked downwardly onto the surface to raise the front end of the vehicle clear of the ground, or at least to allow transfer of weight to allow adhesion to the surface for traction purpose. This may mean that the front of the vehicle is lifted clear of the ground, but preferably it will not. The control of the driving of the creep speed wheel or wheels is effected by control means either on the working apparatus or from the vehicle cabin depending upon the manner in whcih the planer apparatus is associated with the vehicle. This enables the entire assembly to be moved forwards or rearwards as required in order to extend the area in which the planer apparatus can be operated. In an alternative embodiment (not shown) the hood is of a circular construction made up from a series of sections. The apparatus according to the invention can be designed as a small one-man operated self propelled unit or in connection with a vehicle as illustrated in Fig. 1 or Fig. 5 or as a separate unit directly connected to the vehicle or usable in conjunction with the vehicle. The facility to provide creep speed may be provided as illustrated on the vehicle or may comprise a creep speed unit (hydrostatic) embodied in the vehicle transmission or in any other convenient manner. The working apparatus may be designed as a slitter i.e. one or more slitting discs arranged in one or more vertical planes may replace the planing drum. In this connection the planer may be designed so that the planing drum can be removed and replaced by said one or more slitting discs. The concept of converting an existing vehicle to creep speed by adding a creep speed wheel which can be jacked onto the road surface, and where the vehicle is for driving a road working apparatus or is for treating the road surface for example by discharging road surfacing material thereonto, or for spreading treatment material, such as grit and salt, is also a novel and independent invention.

Claims: CLAIMS 1. A road working apparatus comprising a rotary cutter connected to be driven by the drive means and housed in a casing to which suction can be applied to remove spoil created when the cutter is driven and cuts the road surface. 2. Apparatus according to claim 1, wherein the rotary cutter comprises a planing drum having cutting picks theron. 3. Apparatus according to claim 2, wherein the picks are tungsten carbide topped picks. 4. Apparatus according to claim 2 or 3 wherein the picks are arranged in staggered relationship around the drum and are inclined forwardly having regard to the direction of rotation of the drum in use. 5. Apparatus according to claim 2, 3 or 4 wherein suction enhancing flight bars extend transversley of the drum, said bars being of approximately the same radial size as to picks. 6. Apparatus according to claim 5, wherein the casing has skirt means controlling the air gap between the skirt means and the road surface to control the rate of induction of air into the casing when the suction is operational. 7. Apparatus according to any of preceding claims 2 to 6 wherein said casing has a body and said skirt means comprises side plates which are movably mounted on the body, said side plates being adapted to move relative to the body towards the road surface so as to control the gap between the road surface and the body at each side of the body, for enhanced suction effect. 8. Apparatus according to claim 7, wherein the casing has a front and a rear end, and the drum is arranged so that the periphery thereof moves downwardly towards the road surface at the rear end and upwardly from the road surface and into the casing at the front end, and said rear end is relatively open to allow air to be sucked into the casing and at the front end is a flexible seal adapted to engage the road surface to prevent air from escaping at said front end. 9. Apparatus according to any preceding claim wherein the casing has an outlet through which air can be sucked and adjacent said air outlet is an air blocking plate which extends across the casing and prevents air from being carried round by the rotary cutter past the outlet. 10. Apparatus according to any preceding claim, wherein the apparatus comprises a main frame plate which in use lies upright and the drive means, the rotary cutter and casing are carried on the frame cutter as a unit so as to be position adjustable thereon towards and away from the ground so that the cutter can be moved towards and into engagement with the ground to an adjustable extent. 11. Apparatus according to claim 10, wherein the cutter unit is movable about a horizontal axis by adjustment enas. 12. Apparatus according to claim 11, wherein the adjustment means comprises a hydraulic ram. 13. Apparatus according to any of claims 10 to 12 when taken with claims 7, 8 or 9 when dependent upon claim 7 or 8, wherein said side plates are pivotally mounted relative to the casing body so as to be pivotable about the same axis as the cutter unit. 14. Apparatus according to any preceding claim wherein the apparatus comprises a mobile self propelled machine with the suction supplied from a separate suction machine, the two machines being connected by a suction hoze. 15. Equipment comprising apparatus according to any of claims 1 to 13, wherein the apparatus is mounted on a suction sweeper vehicle by which suction is supplied to the apparatus. 16. Equipment according to claim 15, wherein the apparatus is mounted on the front of the vehicle so as to be capable of movement up and down relative to the front of the vehicle, and the said suction hose extends from a spoil collection casing to the apparatus past the driver's cabin.

Inventors: LUPTON WILLIAM GEORGE, LUPTON, WILLIAM, GEORGE
Applicants: LUPTON WILLIAM GEORGE, ROTA PIC LTD, LUPTON, WILLIAM, GEORGE, ROTA-PIC LIMITED
Application year: 1993
Main classification: E01C23
IPC codes: E01C23