GB2315795A - Boom for a road repair vehicle - Google Patents

Abstract

A boom for a road repair vehicle includes a head (26) at the free end of the boom for dispensing a road repair material and at least one hose (16) extending along the boom for delivering the material to the head from a supply of the material on the vehicle. The boom has a pivotal connection (2) to the vehicle for side to side movement of the boom as a whole and is also articulated at at least one point (7) along its length such that the boom may be folded concertina-like for storage substantially horizontally across the front of the vehicle. The boom is connected to the vehicle by a plate 1 and has an insert (19) in the second arm member (12) which is longitudinally moveable relative thereto. The head can also be swung in an arcuate motion about pin (20). U-shaped brackets (14', 14") support hose (16) and are arranged to cater for longitudinal movement of the insert (19). A second hose (25) is also connected to the head (26).

Description

Boom for a Road Repair Vehicle The present invention relates to a boom for a road repair vehicle.

Figure 1 shows a prior art road repair vehicle 10 for repairing potholes 60 in a road surface. The operation of this vehicle is described in U.S. Patent Specifications Nos. 5,263,790 and 5,419,654. The vehicle 10 comprises a wheeled chassis 40 on which a gravel hopper 42, a tank 44 for holding liquid asphalt and a cab 46 are mounted. An extendable and retractable boom 50 is fixed to the front 48 of the cab. A head 52 is carried at the free end of the boom 50 for mixing and applying an asphalt-gravel mixture to a pothole 60, the gravel being supplied to the head 52 from the hopper 42 via a first hose 54 carried by the boom 50 and the asphalt being supplied to the head 52 from the tank 44 via a second hose 56 also carried by the boom 50.

In the prior art vehicle, the boom is raised by a hydraulic cylinder 58 into a vertical storage state. This leads to excess asphalt or gravel dropping from the head 52 onto the windscreen 62 of the vehicle. This can prove to be dangerous if either the windscreen is too dirty to see through or if it is damaged by the gravel.

According to the invention there is provided a boom for a road repair vehicle including a head at the free end of the boom for dispensing a road repair material and at least one hose extending along the boom for delivering said material to the head from a supply of said material on the vehicle, the boom being pivotally connected to the vehicle for side to side movement and also being articulated at at least one point along its length such that the boom may be folded concertina-like for storage substantially horizontally across the front of the vehicle.

An embodiment of the invention will now be described, by way of example, with reference to the accompanying drawings, in which: Figure 1 is a perspective view of a prior art road repair vehicle; Figure 2 is a side view of a boom for a road repair vehicle according to the embodiment of the invention in a retracted state; Figure 3 is a side view of the boom of Figure 2 of the drawings in an extended state; Figure 4 is a top plan view of the boom of Figure 2; Figure 5 is a top plan view of the boom of Figure 2 in a storage position; Figure 6 is a detailed side view of the dispensing head of the boom of Figure 2; and Figure 7 is a front view of the head of Figure 6.

The boom 100 according to the embodiment is mounted on the front of a road repair vehicle via a plate 1 fixed to the front of the vehicle. The vehicle is not shown but it may be a vehicle of the type shown in figure 1 having a gravel hopper and asphalt tank. The boom 100 comprises, as its main structural components, a vertical bracket 10, a first arm member 11 and a second arm member 12.

The bracket 10 is pivotally connected to the plate 1 by means of a bolt 2 for rotation about a substantially vertical axis. In turn, one end of the first arm member 11 is pivotally connected to the bracket 10 by means of a bolt 6 for rotation about a substantially horizontal axis. Finally, one end of the second arm member 12 is pivotally connected to the other end of the arm member 11 by means of a bolt 7 for rotation about a substantially vertical axis, assuming the arm member 11 is horizontal.

The first arm member 11 is of hollow square cross-section, aid the part 12a (Figure 2) of the arm member 12 connected to the arm member 11 is also of hollow square cross-section. However, the arm member 12 has an insert 19 slidably accommodated in the part 12a so that the overall length of the arm member 12 can be varied in the manner of a telescope, to correspondingly vary the overall length of the boom.

A head 26 is carried at the free end of the boom 100 for mixing and applying an asphalt-gravel mixture to a pothole in a road to be repaired.

The gravel is supplied to the head 26 from the vehicle gravel hopper via a first hose 25 carried below the boom 100 and the asphalt is supplied to the head 26 from the vehicle asphalt tank via a second hose 16 carried above the boom 100.

A first hydraulic cylinder 4 is pivotally connected at each end to the plate 1 and the bracket 10 respectively, and a second hydraulic cylinder 5 is pivotally connected at each end to the first arm member 11 and the part 12a of the second arm member 12 respectively, on the same side of the boom as the bolt 7. Extending and retracting the cylinder 4 causes the first arm member 11 to pivot about the axis of the bolt 2 to describe a path indicated by the line D-C in Figure 4. Extending and retracting the cylinder 5 causes the second arm member 12 to pivot about the axis of the bolt 7 to describe a path indicated by the line B-a relative to the first arm member 11.

A third hydraulic cylinder 3 is pivotally connected at each end to the first arm member 11 and the bracket 10 respectively, by bolts 8 and 9 respectively. Extending and retracting the cylinder 3 causes the first arm member 11, and hence the entire boom 100, to pivot about the axis of the bolt 6 so that the end of the boom carrying the head 26 may be raised and lowered as required when in use.

Finally, a fourth hydraulic cylinder 13 is pivotally connected at each end to the part 12a of the second arm member 12 and the insert 19 respectively.

Extending and retracting the cylinder 13 slides the insert 19 into and out of the part 12a to lengthen and shorten the boom 100.

In normal operation the hydraulic cylinder 5 is extended to maintain the first and second arm members 11 and 12 in alignment, Figures 2 to 4.

Then, by appropriately extending and retracting the hydraulic cylinders 4, 3 and 13 respectively the boom 100 is swung from side to side, and/or lifted and lowered, and/or extended and contracted as necessary according to the requirements of the repair, the asphalt/gravel mixture being applied to the repair by the head 26.

However, the articulation of the boom at the bolt 7 connecting the first and second arm members 11 and 12 allows the boom to be folded into a storage position, from a position in which the boom extends horizontally forwardly of the vehicle, by extending the cylinder 4 and retracting the cylinder 5, Figure 5. In the storage position the boom 100 is folded concertina-like substantially horizontally across the front 48 of the vehicle. Therefore, gravel or asphalt dripping from the head 26 does not pose a hazard.

Articulation of the boom at the bolt 7 enables the storage length of the boom to be sufficiently short to fit across the front face of the vehicle without projecting out from either side of the vehicle.

Both hoses 16 and 25 are long enough to accommodate extensions and contractions of the boom 100 in operation of the boom. However, in the case of the top hose 16, precautions are taken to ensure that the hose 16 does not fall into and foul the boom mechanism in the contracted state of the boom. When the boom 100 is extended to its full length, Figure 3, the hose 16 lies flat against the top surface of the arm members 11, 12. In order to prevent the hose 16 dropping over the edge of the boom 100 when contracted, Figure 2, the outer ends of a pair of U-channel guide members 14', 14" are pivoted to the upper surfaces of the part 12a of the arm member 12 and the insert 19 respectively using the same bolts 18' 18" which connect the ends of the hydraulic cylinder 13 to the part 12a and insert 19. The inner ends of the guide members 14', 14" are pivoted together at 15. The hose 16 rests in the U-channel of the members 14' 14" so that when the boom 100 is contracted the arms 14', 14" rise up while retaining the hose 16 in their respective U-channels. When the boom 100 extends, the guide members 14',14" drop towards the arm member 12 with the hose 16 still resting in the respective U-channels, Figure 3.

As best seen in Figures 6 and 7 a hydraulic motor 21 is fixedly mounted on the free end of the insert 19. The spindle 21a of the motor extends away from and parallel to the longitudinal axis of the insert 19. An offset cam 22 is fixed to the spindle and a slotted arm 23 acting as a cam follower is located over and extends downwardly from the cam 22. The lower end of the slotted arm 23 is fixed to a rigid front end 24 of the hose 25. The front end 24 of the hose carries the head 26 and is pivotally connected to the underside of the insert 19 by a bolt 20. Thus the head 26 is mounted for arcuate side-to-side motion below the free end of the boom along an arcuate path A-B, Figure 7, having a centre of curvature co-incident with the bolt 20. Rotation of the motor spindle causes the head 26 to be deflected side-to-side along the arcuate path A-B. Use of this apparatus reduces the need for the operator to constantly move the boom 100 back and forth to spread gravel/asphalt over a section of road.

The invention is not limited to the embodiments described herein which may be modified or varied without departing from the scope of the invention.

Claims (7)

1. A boom for a road repair vehicle including a head at the free end of the boom for dispensing a road repair material and at least one hose extending along the boom for delivering said material to the head from a supply of said material on the vehicle, the boom being pivotally connected to the vehicle for side to side movement and also being articulated at at least one point along its length such that the boom may be folded concertina-like for storage substantially horizontally across the front of the vehicle.

2. A boom as claimed in claim 1, further including drive means to impart side-to-side motion of the dispensing head relative to the free end of the boom.

3. A boom as claimed in claim 2, wherein the head is mounted for arcuate side-to-side motion below the free end of the boom and the drive means includes a motor at the free end of the boom which drives the head by means of a cam connected to the motor and a cam follower connected to the head.

4. A boom as claimed in claim 1, 2 or 3, wherein the boom comprises a first arm member having one end pivotally connected to the front of the vehicle for both side-to-side and up-and-down motion relative to the vehicle and a second arm member having one end pivoted to the other end of the first arm member for side-to-side motion relative to the first arm member, the second arm member being adjustable in length.

5. A boom as claimed in claim 4, wherein the hose extends along the top of the boom and is carried over the adjustable second arm member by an articulated guide.

6. A boom for a road repair vehicle constructed and arranged substantially as herein described with reference to, and as illustrated in, Figures 2 to 7 of the accompanying drawings.

7. A road repair vehicle equipped witha boom as claimed in any one of the preceding claims.