GB2097844A - Asphalt laying machines - Google Patents

Abstract

A paver having an auger box 6 from which asphalt may be deposited incorporates in front of the auger box 6 a shrouded heater 10 by which the road base on which the asphalt is to be deposited may be preheated. <IMAGE>

Description

SPECIFICATION Improvements in or relating to asphalt layer This invention relates to pavers by which asphalt may be laid and is concerned to facilitate the use of pavers in cold weather.

According to the present invention, there is provided a road paver including an auger box from which asphalt may be laid and heating means extending across the width of, and forwardly of, the auger box by which the road base on which the asphalt is to be laid may be heated.

By means of the heater, the temperature of the road base may be raised before the asphalt is deposited. It may be considered unadvisable to lay to asphalt on a road base of which the temperature is lower than 50C.

By way of example, a particular embodiment of the invention will now be described with reference to the accompanying drawings in which: Figure 1 shows in side view the major, central, part of a road paver; and Figure 2 is a cross-section, on a larger scale, of a detail of Figure 1.

The paver shown in Figure 1 is essentially of a known construction and comprises a chassis 1 mounted on road wheels 2 and carrying a driving seat 3 and controi equipment 4 located behind a power source 5. Behind the road wheels 2 is an auger box 6 from which molten asphalt may be deposited on the road base over which the paver runs and, behind that, a screed 7.

Lying forwardly of the auger box 6 but behind the road wheels 2 is a unit comprising heating means 10 carried below an insulating shroud 11.

The heating means comprises a pair of bar burners 1 2 extending end-to-end across the width of the auger box 6 and provided with gas nozzles (indicated at 14) so that flames from the nozzles are directed downwardly and rearwardly. A pipe 1 5 by which gas is supplied to the bar burners 12 extends up to a source of supply (not shown).

The insulating shroud 11 is effective to protect other parts of the paver from the heat generated by operation of the burners 14. It comprises a horizontal part 1 a and two downwardly diverging wing parts 1 b formed from insulating material within a protective casing of stainless steel. The burner bars lie nearer the forward wing than the rear wing. Brackets 19 are welded to the outer metal casing and are joined to the chassis 1 by arms (not shown) connected at their lower ends to the brackets at 1 9a and at their upper arms to the chassis 1. Plates 20 are bolted to the brackets 1 9 and the bar burners 12 are welded for support to the plates at 21.

The bar burners 12 are provided with a pilot flame (not shown) and the passage of gas from the supply to the pipe 1 5 is controlled by a valve that is automatically closed when the clutch through which the paver is driven is disengaged so that the burners are operative only when the paver is in motion.

By means of the downwardly and rearwardly directed flames discharging from the bar burners 10, the temperature of the road base may be raised in cold weather to a temperature appropriate to the deposition of asphalt from the auger box 6 that immediately follows the burners.

The shroud 11 not only protects the adjacent parts of the apparatus from being overheated but will direct heat down on to the road base.

1. A road paver including an auger box from which asphalt may be laid and heating means extending across the width of, and forwardly of, the auger box by which the road base on which the asphalt to be laid may be heated.

2. A road paver as claimed in claim 1 in which the heating means lies beneath a thermally insulating shroud.

3. A road paver as claimed in either of the preceding claims in which the heating means includes a bar burner providing a row of nozzles from which gas jets may discharge.

4. A road paver as claimed in claim 3 in which the nozzles are such that the jets discharge downwardly and rearwardly.

5. A road paver as claimed in claim 2 or either of claims 3 and 4 when appended to claim 2 in which the shroud is mounted on the chassis of the paver and the heating means is mounted on the shroud.

6. A road paver having an auger box and provided with heating means in front of the auger box, substantially as described with reference to, and as illustrated by the accompanying drawings.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (6)

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Improvements in or relating to asphalt layer This invention relates to pavers by which asphalt may be laid and is concerned to facilitate the use of pavers in cold weather. According to the present invention, there is provided a road paver including an auger box from which asphalt may be laid and heating means extending across the width of, and forwardly of, the auger box by which the road base on which the asphalt is to be laid may be heated. By means of the heater, the temperature of the road base may be raised before the asphalt is deposited. It may be considered unadvisable to lay to asphalt on a road base of which the temperature is lower than 50C. By way of example, a particular embodiment of the invention will now be described with reference to the accompanying drawings in which: Figure 1 shows in side view the major, central, part of a road paver; and Figure 2 is a cross-section, on a larger scale, of a detail of Figure 1. The paver shown in Figure 1 is essentially of a known construction and comprises a chassis 1 mounted on road wheels 2 and carrying a driving seat 3 and controi equipment 4 located behind a power source 5. Behind the road wheels 2 is an auger box 6 from which molten asphalt may be deposited on the road base over which the paver runs and, behind that, a screed 7. Lying forwardly of the auger box 6 but behind the road wheels 2 is a unit comprising heating means 10 carried below an insulating shroud 11. The heating means comprises a pair of bar burners 1 2 extending end-to-end across the width of the auger box 6 and provided with gas nozzles (indicated at 14) so that flames from the nozzles are directed downwardly and rearwardly. A pipe 1 5 by which gas is supplied to the bar burners 12 extends up to a source of supply (not shown). The insulating shroud 11 is effective to protect other parts of the paver from the heat generated by operation of the burners 14. It comprises a horizontal part 1 a and two downwardly diverging wing parts 1 b formed from insulating material within a protective casing of stainless steel. The burner bars lie nearer the forward wing than the rear wing. Brackets 19 are welded to the outer metal casing and are joined to the chassis 1 by arms (not shown) connected at their lower ends to the brackets at 1 9a and at their upper arms to the chassis 1. Plates 20 are bolted to the brackets 1 9 and the bar burners 12 are welded for support to the plates at 21. The bar burners 12 are provided with a pilot flame (not shown) and the passage of gas from the supply to the pipe 1 5 is controlled by a valve that is automatically closed when the clutch through which the paver is driven is disengaged so that the burners are operative only when the paver is in motion. By means of the downwardly and rearwardly directed flames discharging from the bar burners 10, the temperature of the road base may be raised in cold weather to a temperature appropriate to the deposition of asphalt from the auger box 6 that immediately follows the burners. The shroud 11 not only protects the adjacent parts of the apparatus from being overheated but will direct heat down on to the road base. CLAIMS

1. A road paver including an auger box from which asphalt may be laid and heating means extending across the width of, and forwardly of, the auger box by which the road base on which the asphalt to be laid may be heated.

2. A road paver as claimed in claim 1 in which the heating means lies beneath a thermally insulating shroud.

3. A road paver as claimed in either of the preceding claims in which the heating means includes a bar burner providing a row of nozzles from which gas jets may discharge.

4. A road paver as claimed in claim 3 in which the nozzles are such that the jets discharge downwardly and rearwardly.

5. A road paver as claimed in claim 2 or either of claims 3 and 4 when appended to claim 2 in which the shroud is mounted on the chassis of the paver and the heating means is mounted on the shroud.

6. A road paver having an auger box and provided with heating means in front of the auger box, substantially as described with reference to, and as illustrated by the accompanying drawings.