AU628360B2

AU628360B2 - Spraying apparatus

Info

Publication number: AU628360B2
Application number: AU38892/89A
Authority: AU
Inventors: Ian Paul Tevlin
Original assignee: COMMISSIONER OF MAIN ROADS IN
Current assignee: COMMISSIONER OF MAIN ROADS IN STATE OF WESTERN AUSTRALIA
Priority date: 1988-07-25
Filing date: 1989-07-25
Publication date: 1992-09-17
Anticipated expiration: 2009-07-25
Also published as: AU3889289A

Description

AU, iALIA COMPLETE AFTER PROVISIONAL PATENTS ACT 1952 6 SPECIFICATION NO. PI 9450 COMPLETE SPECIFICATION fORIGINAL) FOR OFFICE USE: Application Number: Lodged: Class Int. Class Complete Specification Lodged: Accepted: Published: Priority: j(elated Ar.: C C 00 0- 1 EATPRH A

AUTRLI

00 Actual Inventor(s): Adrs fo0erie IAN PAUL TEVLIN Kelvin Lord Co., 4 Douro Place, WEST PERTH, Western Australia 6005.

Complete Specification for the invention entitled:.

"1SPRAYING APPARATUS" The following statement is a full description of this invention, including the best method of performing it known to me/ us 2 The present invention relates to spraying apparatus.

In particular, the present invention relates to an apparatus for spraying road surfacing material onto a road, pavement or the like.

This type of spraying apparatus is generally carried on a vehicle. The road surfacing material is held in a tank on the vehicle and is sprayed onto the road, or pavement, from spray nozzles as the vehicle moves along the road, or pavement. The spray nozzles are provided on a spray bar in 10 fluid communication with the tank. The spray bar i! *W 0 positioned transverse to the direction of travel of the vehicle.

This type of spraying apparatus may be used to spray road surfacing material onto existing road, or pavement, surfaces which have deteriorated due to wear. In such situations, the existing road, or pavement, surface is effectively being re-surfaced by a fresh spraying of road surfacing material.

When re-surfacing existing road, or pavement, surfaces in this manner it is desirable that the application rate of the road surfacing material is variable along the spray bar, ie. in the direction transverse to the direction of travel of the vehicle. However, conventional single sp.-ay bar spraying apparati are unable to achieve such a result to a satisfactory standard.

I daoudance wiLh e dbpecL uf the present m W nE there is provided spraying appa comprising at least two spray bars leprovided with at least one row of spray z f es arranged lon itudinally thereon said spray bs i i 2a In accordance with one aspect of the present invention there is provided spraying apparatus for spraying material onto a surface comprising at least two spray bars each provided with at least one row of spray nozzles arranged longitudinally thereon, each of said spray bars connected to respective pump means arranged to pump said material to said spray bars to be sprayed through said spray nozzles, wherein said material is sprayable through selected said spray nozzles and said respective pump means are operable to pump said material at respective selected rates such that the rate of spray of said material onto said surface in the longitudinal direction of said spray bars is variable.

e _I i 3 being connected to respective first and second pum ers arranged to pump road surfacig-nalraal to said spray bars and t arod spray nozzles.

The present invention will now be described, by way of example, with reference to the accompanying drawings, in which: Figure 1 is a side view of a vehicle incorporating an apparatus for spraying road surfacing material onto a road, or pavement, in accordance with the present invention; Figure 2 is a rear view of the vehicle shown in Figure 1; Figure 3 is a "close-up" side view of the spray bars of the apparatus in accordance with the present invention; Figure 4 is a "close-up" side view of the details of one of the spray bars shown in Figure 3; Figure 5 is an end view of the reservoir tank for the road surfacing material; Figure 6 is a functional block diagram of a pump control system for the variable displacement hydraulic pumps; 4 00 Figure 7 is a schematic diagram of the manner in which material may be sprayed onto an existing road surface, or pavement, having primer sealed widenings; and, Figure 8 is a schematic diagram of the manner in which material may be sprayed onto an existing road surface, or pavement, having variations in texture.

In Figures 1 and 2, there is shown a vehicle incorporating an apparatus 12 for spraying road surfacing material onto a road.

The apparatus 12 comprises a pair of spray bars 14 and 16, 0 respectively. The spray bars 14 and 16 are shown in AIE i I r- -4- "close-up" in Figure 3.

Each of the spray bars 14 and 16 is provided with a pair of turn-up joints 18 at its mid-section. The turn-up joints 18 essentially separate each spray bar 14 and 16 into two halves. The turn-up joints 18 allow the spray bars 14 and 16 to be raised from their horizontal spraying positions to near vertical non-operative positions. The non-operative positions are used when the vehicle 10 is travelling to or from a work site.

S 10 In Figure 1, the spray bars 14 and 16 are shown in the near vertical positions, whilst in Figures 3 and 4, they are shown in their horizontal spraying positions. In Figure 2, ,for ease of illustration, the spray bars 14 and 16 are shown in both the horizontal spraying positions and the near vertical, non-operative positions; however, it is

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.0 understood that the spray bars 14 and 16 can be in only one of these positions at any one time.

Each of the spray bars 14 and 16 is provided with spray nozzles 20, best seen in Figures 3 and 4. Each spray 20 nozzle 20 is provided with a latch type tap 22 having an j .operating lever 24. Thus, when any particular spray nozzle(s) 20 is not required to spray material therefrom, the operating lever 24 is shifted to unlatch that particular spray nozzle(s) Thus, the road surfacing material may be sprayed from any selected spray nozzles 20, as required.

Camber adjustors 25 may be provided to ensure that both spray bars 14 and 16 are level with the road surface.

Preferably, the spray nozzles 20 spray material therefrom in a substantially planar fan shaped spray pattern.

Preferably, all of the spray nozzles 20 on the spray bars 14 and 16 are of the same type.

Preferably, the spray nozzles 20 are Copley orifice type nozzles, which are known in the art.

Each spray bar 14 and 16 is connected to a respective pump 26 and 28 by hoses and/or pipes 30 and 32, respectively.

Each pump 26 and 28 is powered by a respective hydraulic motor 34 and 36.

10 The pumps 26 and 28, hoses or pipes 30 and 32, and the hydraulic motors 34 and 36 are best seen in Figures 1, 2 and 3.

O *The pumps 26 and 28 are connected to a reservoir tank 38 containing road surfacing material 40 that is to be sprayed from the spray nozzles 0SOS So Heating means and an agitation system to, respectively, Se"heat and agitate the road surfacing material 40 contained in the reservoir tank 38 are provided.

The heating means comprises gas vaporizing burners 42 connected to horizontal re-entrant flue tubes 44 in the reservoir tank 38. The flue tubes 44 are installed as low as possible in the reservoir tank 38 to take advantage of thermal gradients in the road surfacing material 40 when it is being heated in the reservoir tank 38. This is best seen in Figures 1 and Gas bottles 45 contain gas which is supplied to the gas vaporizing burners 42 for combustion.

Preferably, the gas burners 42 are Liquid Petroleum Gas burners and the gas is Liquid Petroleum Gas.

m II I 6 The agitation system in the reservoir tank 38 comprises agitation distribution pipes 46, extending longitudinally of the reservoir tank 38, and provided with nozzles 48.

The nozzles 48 are arranged to direct material exiting therefrom toward the bottom of the reservoir tank 38.

Metal plates 50 are arranged near the outlets of the nozzles 48 to deflect exiting material such that it fans out to produce turbulence and agitation. This is shown by the arrows inside the reservoir tank 38 in Figure 10 The material 40 in the reservoir tank 38 is circulated through the agitation system by the pumps 26 and 28, unless the pumps 26 and 28 are being used to pump material 40 to *i *0 ems.e the spray bars 14 and 16.

The above described agitation system relies upon the material 40 being pre-heated and pre-blended to a homogeneous consistency before it is loaded into the reservoir tank 38.

This may be done in a separate blending device (which does not form a part of the present invention).

'The agitation system within the reservoir tank 38 is then required only to maintain a homogenous blend of the material The reservoir tank 38 further comprises loading tubes 47 in the upper region thereof. The loading tubes 47 are used to the load the material 40 into the reservoir tank 38.

The reservoir tank 38 may further comprise a pair of transverse baffles 49a and a central longitudinal baffle 49b. These are shown in Figures 1 and 5, respectively.

The vehicle 10 is provided with a manual gear box Si 7 transmission (not shown) and is fitted with a variable speed engine governor (not shown) and hand throttle (not shown).

A closed loop hydrostatic system is directly connected to the engine (not shown) of the vehicle 10. The hydrostatic system comprises two variable displacement hydraulic pumps 52.

The hydrostatic system is provided with oil coolers 54 to dissipate heat.

10 The two variable displacement hydraulic pumps 52 are directly driven by the engine of the vehicle 10 through a splitter gearbox (not shown).

*The two variable displacement hydraulic pumps 52 are operatively connected to a respective hydraulic motor 34 and 36.

S. Control of the variable displacement hydraulic pumps 52 is effected from within the cabin 56 of the vehicle 10 by two independant, identical open loop electronic control systems.

In Figure 6 there is shown a functional block diagram of a r pump- ontrol system.

o n* Input control for the variable displacement hydraulic pumps 52 is effected by way of digit type thumbwheels 58 and respectively such that the solenoid current controlling the positions of swash plates in the variable displacement hydraulic pumps 52 progresses in a linear fashion with an external potentiometer being used for final adjustment of the speeds of the pumps 26 and 28. The digit thumbwheels 58 and 60 also act as a memory aid for the operator. A i -i i 8 single toggle switch operates forward-neutral-reverse positions of the system whilst liquid crystal displays 62 and 64 show the actual speeds of the pumps 26 and 28, respectively.

The variable displacement hydraulic pumps 52 are set to produce optimum nominated nozzle output when the engine of the vehicle 10 is set to produce correct road speed for any nominated rate of application of material 40 onto a road, eo or pavement.

10 Once the variable displacement hydraulic pumps 52 are set, Se 0 the output of the hydraulic motors 34 and 36, which •respectively power the pumps 26 and 28, will be directly 00 S"proportional to the engine speed of the vehicle 10. Hence, the output of material 40 through the spray nozzles 20 will also be directly proportional to the engine speed of the

OOSO

vehicle 10. This means that the hydraulic systems are not flow compensated.

As a safety precaution, overspeed protection means for the pumps 26 and 28 is provided to prevent pump damage in case 20 a high pump speed is selected at low engine speed, and the engine speed then increased to maximum.

0 00 The rate of application of material 40 is proportional to the output of material 40 through the spray nozzles divided by the road speed of vehicle 10. Additionally, the output of the material 40 and the road speed of the vehicle are proportional to the engine speed of the vehicle Thus, the rate of application of material 40 is a constant.

Accordingly, if the apparatus 12 is initially set correctly, it has the ability to spray the nominated rate 9 S. S S So 0*0O 0O S* S *0

S

So 0 *500 S S 00 S 0 *5 0S 00 S S 05 of application of material 40 irrespective of variations in the road speed of the vehicle Since the road speed of the vehicle 10 and the output of the pumps 26 and 28 are proportional to the engine speed of the vehicle 10, any change in engine speed after the initial setting of the apparatus 12 does not affect the rate of application of the material However, variations in the road speed of the vehicle beyond +50% and -25% will affect the output of a Copley A4 10 type nozzle, with nominal flow of 18.2 L/min, to an extent that the sprayed road, or pavement, may have an unacceptable transverse distribution.

For any nominated rate of application of material 40 and configuration of the spray bars 14 and 16 (ie the number of nozzles 20 latched for operation), the ratio of output of material 40 to road speed of the vehicle 10 is a constant.

Additionally, both the output of material 40 and the road speed of tne vehicle 10 are proportional to the engine speed of the vehicle 10. Thus, to change the rate of application of the material 40, the ratio of output of material 40 to road speed of the vehicle 10 must be changed.

To change the rate of application of material 40 whilst retaining the same configuration of spray bars 14 and 16, the road speed of the vehicle 10 is changed by re-setting the engine speed of the vehicle 10. Then, the variable displacement hydraulic pumps 52 are adjusted to produce the same output of material 40 from the spray nozzles The output of material 40 from the spray nozzles 20 will 1 b r i

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i- t L 10 always depend on the number of spray nozzles 20 that are spraying at that particular time, ie. the configuration of the spray bars 14 and 16.

The apparatus 12 of the present invention enables the material 40 to be sprayed from the nozzles 20 at a transversely variable material application rate, over the length of the spray bars 14 and 16, ie. across the width of the section of road or pavement, that is to be sprayed.

Such a transversely variable material application rate is 10 required to enable certain road or pavement, surfaces to be readily and effectively sprayed with road surfacing .o material. In particular, such performance is required where the road or pavement, has variations in surface texture arising from road widening and increased traffic flow which has produced a relatively low surface texture in "the wheel paths. This is shown in Figures 7 and 8.

In Figure 7, there is shown, in schematic type form, the manner in which the material 40 miay be sprayed from the spray bars 14 and 16 (designated main bar and auxiliary bar, respectively, in each of Figures 7 and 8) onto an i existing road or pavement surface, with primer sealed widenings. As can be seen in Figure 7 not all of the spray nozzles 20 of the auxiliary bar are latched for operation.

As can be seen from the combined effect of the spray bars 14 and 16, the maximum sprayed ratio is 3:1 relative to the main bar.

Similarly, in Figure 8 there is shown the manner in which the material 40 may be sprayed from the spray nozzles 20 of the spray bars 14 and 16 onto an existing road, or pavement 11 surface, with variations in texture.

As can be seen from the combined effect of the spray bars 14 and 16, the maximum sprayed ratio is shown as 2:1 relative to the main bar.

The apparatus 12 enables the transversely variable material application rate ratio to be infinitely variable up to substantially 3:1 at any nominated position on the road or pavement surface.

Further, due to the use of two spray bars 14 and 16, the 10 apparatus 12 enables a doubling of spraying road speed which, together with maximizing nozzle flow, can provide productivity advantages over conventional spraying apparatus.

The apparatus 12 of the present invention, may be used to spray a range of road surfacing materials including hot and cold bituminous blends comprising hydrated lime and/or granulated rubber particles and other additives.

The manner of operation of the present invention will now be described.

20 I.n use, the spray bars 14 and 16 are positioned in their horizontal spraying positions, with the reservoir tank 38 containing a load of road surfacing material The required spray nozzles 20 on the spray bars 14 and 16 are latc__d for operation such that the required configuration of the spray bars 14 and 16 is effected.

The application rate of the material 40 is then determined and the corresponding appropriate engine speed for the vehicle 10 is selected.

The variable displacement hydraulic pumps 52 are then set 12 to produce optimum output of the spray nozzles 20. The variable displacement hydraulic pumps 52 are set by way of the thumbwheels 58 and 60, as hereinbefore described. The pumps 26 and 28 are powered by the variable displacement hydraulic pump 52 via the hydraulic motors 34 and 36 respectively. Thus, the output of the pumps 26 and 28 is determined by the setting of the variable displacement hydraulic pumps 52.

Further, the actual speeds of the pumps 26 and 28 are displayed on the liquid crystal displays 62 and 64. The pumps 26 and 28 are then operated to pump material from the reservoir tank 38 via respective hoses and/or pipes 30 and 32 to the spray bars 14 and 16'.

The material 40 is then sprayed from the spray nozzles as the vehicle 10 moves along the road surface, in accordance with the selected settings.

Since the hydraulic pumps 52 independently power the respective pumps 26 and 28, the output speeds of the pumps 26 and 28 which supply the sprays bars 14 and 16, 20 respectively, are independently adjustable. This in combination with the selective operation of the spray nozzles 20 of the spray bars 14 and 16, enables the apparatus 12 to spray material 40 from the spray nozzles of the spray bars 14 and 16 with a transversely variable 25 material application rate. The transversely variable material application rate is infinitely variable up to a ratio of substantially 3:1 relative to the main bar.

a^ Modifications and variations such as would be apparent to a skilled addressee are deemed within the scope of the r A present invention.

Claims

1. Spraying apparatus for spraying material onto a surface comprising at least two spray bars each provided with at least one row of spray nozzles arranged longitudinally thereon, each of said spray bars connected to respective pump means arranged to pump-said material to said spray bars to be sprayed through said spray nozzles, wherein said material is sprayable through selected said spray nozzles and said respective pump means are operable to pump said material at respective selected rates such that the rate of spray of said material onto said surface in the longitudinal direction of said ,pray bars is variable.

2. Spraying apparatus according to claim 1, wherein said spray nozzles are provided with latch means such that they are individually latchable into an operative spraying condition such that said material is sprayable from selected said spray nozzles.

3. Spraying apparatus according to claim 1 or 2, wherein said respective pump means are powered by respective hydraulic motor means.

4. Spraying apparatus according to claim 3, further comprising hydrostatic system means which comprises respective variable displacement pump means which are operatively connected to respective said hydraulic motor 25 means.

Spraying apparatus according to claim 4, wherein said hydrostatic system means further comprises cooler means to dissipate heat.

6. Spraying apparatus according to claim 4 or 5, wherein 0 i 13a said respective variable displacement hydraulic pump means are controlled by respective independent open loop electronic control systems.

7. Spraying apparatus according to any one of the preceding claims, wherein said respective pump means I0 ooe 20 *o 25 c xl i i-C~ 14 *0f. 4 0G 14 S S 0 6 0 *r 0 *6 9 a) B U are connected to reservoir means for holding material to be sprayed from said spray nozzles.

8. Spraying apparatus accbrding to Claim 7, wherein said reservoir means is provided with heating means to heat said material held therein.

9. Spraying apparatus according to Claim 8, wherein said heating means comprises burner means connected to re-entrant flue tube means, said re-entrant flue tube means being located in said reservoir means.

10 10. Spraying apparatus according to any one of Claims 7 to 9, wherein said reservoir means is provided with agitation means to agitate said material held therein.

11. Spraying apparatus according to Claim 10, wherein said agitation means comprises agitation distribution pipe means provided with nozzles to direct said material exiting therefrom toward the bottom of said reservoir means.

12. Spraying apparatus according to Claim 11, wherein deflection means is provided to deflect said exiting material such that it fans out to produce turbulence and agitation in said reservoir means.

13. Spraying apparatus according to Claim 12, wherein said deflection means comprises plates provided near the outlets of the nozzles of said distribution pipe means.

14. Spraying apparatus according to any one of Claims 7 to 13, wherein said reservoir means is provided with baffle means.

Spraying apparatus according to Claim 14, wherein said baffle means comprises two baffle plates disposed in a substantially transverse manner and a baffle plate disposed 15 in a substantially longitudinal manner in said reservoir means.

16. Spraying apparatus according to any one of the preceding claims, wherein said apparatus is mounted oii a vehicle and said spray bars are arranged such that they are positionable in a manner one behind the other and substantially transverse to the direction of travel of said vehicle.

17. Spraying apparatus according to claim 16, wherein said respective variable displacement hydraulic pump means are directly driven by the engine of said vehicle through a splitter gearbox.

18. Spraying apparatus according to any one of the preceding claims, wherein said spray nozzles spray material therefrom in a substantially planar fan shaped spray pattern.

19. Spraying apparatus substantially as hereinbefore described with reference to the accompanying drawings. S. DATED OCTOBER 18 1991 TRANSPORT AND ENVIRONMENT OF THE 25 STATE OF WESTERN AUSTRALIA e By their Patent Attorneys KELVIN LORD AND COMPANY PERTH, WESTERN AUSTRALIA