WO1999035345A1

WO1999035345A1 - Excavation apparatus and a method of use thereof

Info

Publication number: WO1999035345A1
Application number: PCT/AU1999/000010
Authority: WO
Inventors: Kevin Francis Patrick Barry, Jr.
Original assignee: Barry Kevin Francis Patrick Jr
Priority date: 1998-01-09
Filing date: 1999-01-11
Publication date: 1999-07-15
Also published as: AUPP125598A0

Abstract

The excavating device (1) includes a pressurised cutting fluid source (2) communicating with an outlet (3) adapted to spray cutting fluid (not shown) so as to excavate material (4) adjacent the outlet. The device (1) also includes suction means (5) disposed so as to suck detritus (not shown) resulting from excavated material away from the outlet (3). In one preferred embodiment the cutting fluid is, or includes, water and in another preferred embodiment the cutting fluid is, or includes, air. The pressure at which the cutting fluid is sprayed from the outlet (3) will vary depending upon the strength of the material being excavated. For example, when excavating concrete, bitumen or rock, the required pressure will usually be greater than that for sand or soil. If the cutting fluid is water, the preferred embodiment typically utilises pressures in excess of 2000 psi. A more preferable pressure range is between 3000 psi and 40,000 psi, and a still more preferable pressure range is between 4000 psi and 20,000 psi. The preferred method for excavating according to the present invention includes the following steps: (a) providing a pressurised cutting fluid source (2) communicating with an outlet (3) adapted to spray cutting fluid (not illustrated); (b) spraying cutting fluid from said outlet (3) so as to excavate material adjacent said outlet (3); and (c) using suction means disposed proximate said outlet to suck detritus resulting from excavated material away from the outlet (3).

Description

TITLE: EXCAVATION APPARATUS AND A METHOD OF USE THEREOF

Field Of The Invention

The present invention relates to a method and apparatus for excavation.

The invention has been developed primarily for use in digging holes to access

sewers in areas where other services such as gas mains or electrical cables may be

buried. However, it will be appreciated that the invention is not limited to this particular

field of use.

Background To The Invention

Prior art methods for excavating holes typically involve solid digging implements

such as shovels which require a high degree of manual labour when excavating.

Mechanically assisted excavating machines, for example bobcats, bulldozers, backhoes

and loaders all use a similar basic principle to that of the humble shovel. In particular,

the aforementioned mechanically assisted excavating devices utilise solid scoops of

varying configurations which cut into the ground. A disadvantage shared by all of the

aforementioned prior art excavating devices may be experienced when excavating

regions having various submerged services such as gas pipes, water mains, electrical or

optical fibre cables, and the like. When the prior art excavating implements strike this

type of submerged service, there is a substantial risk that the scoop will inadvertently

damage or sever the service. This may result in disruptions to services which can have

unpredictable and potentially ^ery expensive ramifications. For example, if a

telecommunications optical fiber is inadvertently severed, a large number of users of the

telecommunications system may be adversely affected, potentially resulting vast unpredictable economic loss Additionally, once damaged or ruptured, further expense

will be incurred in repairing the affected service.

A further disadvantage associated with the mechanically assisted excavating

devices mentioned above is the substantial room required for their operation, which may

be a limiting factor when excavating in narrow confines. Also, the operation of

mechanical excavators often causes significant noise.

Disclosure Of The Invention

It is an object of the present invention to overcome or ameliorate at least one of the

disadvantages of the prior art, or to provide a useful alternative.

According to a first aspect of the invention there is provided an excavating device

including:

a pressurised cutting fluid source communicating with an outlet adapted to spray

cutting fluid so as to excavate material adjacent said outlet; and

suction means disposed so as to suck detritus resulting from excavated material

away from said outlet.

Preferably the cutting fluid is, or includes, water provided at a pressure of greater

than 2000 psi and dispensed from the outlet at a rate of less than 200 litres per minute.

More preferably the pressure exceeds 4000 psi and the flow rate is less than 25 litres per

minute.

According to another aspect of the invention there is provided a method of

excavating including the following steps:

(a) providing a pressurised cutting fluid source communicating with an outlet

adapted to spray cutting fluid; (b) spraying cutting fluid from said outlet so as to excavate material adjacent

said outlet; and

(c) using suction means disposed proximate said outlet to suck detritus

resulting from excavated material away from said outlet.

Specific embodiments in accordance with the invention will now be described by

way of non-limiting examples.

Detailed Description Of Specific Embodiments

The accompanying drawings depict the following:

Figure 1 is a schematic depiction of an embodiment of an excavating device

according to the invention;

Figure 2 is a side view of an embodiment of a nozzle according to the invention;

Figure 3 is a bottom view of the nozzle shown in figure 2;

Figure 4 is a side view of another embodiment of a nozzle according to the

invention;

Figure 5 is a bottom view of the nozzle shown in figure 4;

Figure 6 is a side view of yet another embodiment of a nozzle according to the

invention;

Figure 7 is a side view of a cutting fluid hose and a suction hose according to the

invention;

Figure 8 is a side view of an embodiment of the invention;

Figure 9 is a side view similar to that of figure 7, but also showing a camera; and

Figure 10 is a perspective view of a gantry according to the invention. Referring to the drawings, the excavating device 1 includes a pressurised cutting

fluid source 2 communicating with an outlet 3 adapted to spray cutting fluid (not shown)

so as to excavate material 4 adjacent the outlet. The device 1 also includes suction

means 5 disposed so as to suck detritus (not shown) resulting from excavated material

away from the outlet 3.

In one preferred embodiment the cutting fluid is, or includes, water and in another

preferred embodiment the cutting fluid is, or includes, air.

The pressure at which the cutting fluid is sprayed from the outlet 3 will vary

depending upon the strength of the material being excavated. For example, when

excavating concrete, bitumen or rock, the required pressure will usually be greater than

that for sand or soil. If the cutting fluid is water, the preferred embodiment typically

utilises pressures in excess of 2000 psi. A more preferable pressure range is between

3000 psi and 40,000 psi, and a still more preferable pressure range is between 4000 psi

and 20,000 psi.

The preferred embodiment advantageously utilises a combination of high water

pressure with a low water pumping rate. This helps to minimise the total volume of

water which must be sucked by the suction means 5 from the excavated hole.

Additionally, it means that less water combined with detritus must be stored. In the

preferred embodiment cutting fluid is ejected from the outlet 3 at a rate of less than 200

litres per minute. Indeed, flow rates of as low as 100, 25 or 15 litres per minute have

been successfully used in secret trials. The cutting fluid flows from the pressurised cutting fluid source 2 to the outlet 3

via a cutting fluid hose 6. Various nozzles 7, as shown in Figures 2, 3 and 4, are

detachably disposed upon the cutting fluid hose 6 to form the outlet 3.

Figures 2 and 3 show a nozzle 7 rotably disposed upon the cutting fluid hose 6

with an axis of rotation 8. This nozzle 7 includes a first aperture 9 which is off-set from

the axis of rotation 8 and is oriented such that the ejection of a stream of cutting fluid 10

through the first aperture 9 promotes rotation of the nozzle 7. This rotation results in the

stream of cutting fluid 10 forming a surface of rotation which effectively forms a cutting

cone (not shown). The nozzle 7 further includes a second aperture 11 disposed opposite

the first aperture 9 such that the axis of rotation 8 lies substantially intermediate the first

and second apertures 9 and 11. The second aperture 11 is oriented such that ejection of a

stream of cutting fluid 12 through the second aperture 11 also promotes rotation of the

nozzle 7. The stream of cutting fluid 12 aligns, through rotation of the nozzle 7, with the

stream of cutting fluid 10 to form a single cutting cone. In other words, this nozzle

arrangement results in a fairly broadly dispersed cone formed from two separate streams

of high pressurised water 10 and 12. Hence, this nozzle provides a cutting implement of

relatively low to intermediate cutting force. It is particularly suited to excavating soft

material such as sand or soil.

The cutting strength of each of the nozzles generally varies inversely

propositionally to the distance from the outlet. Accordingly, material close to the nozzle

will be subject to a stronger cutting force, whereas material distant from a nozzle will be

subject to a minimal cutting force. For these reasons, the invention is well suited to

excavating in regions suspected of containing submerged services as sewer pipes, electrical cables and the like. This is particularly true of the rotating nozzle as, at a

distance of approximately 20cm away from the nozzle, the stream is strong enough to

excavate soil without damaging submerged services. However it is important to ensure

that the nozzle is not brought into excessively close proximity to services as the cutting

force may then be sufficient to damage some services.

The nozzle shown in Figures 4 and 5 is better suited to applications requiring high

cutting intensity. This version of the nozzle 7 does not rotate. Rather, it includes a

single aperture 12 shaped to eject the cutting fluid in a narrow stream 13. This nozzle 7

is useful for cutting through hard materials such as bitumen, concrete, rock and the like.

Due to the high cutting intensity of the stream 13, greater care should be taken to ensure

that services are not inadvertently ruptured by accidentally placing this version of the

nozzle 7 too close to submerged surfaces. This version of the nozzle 7 is typically used

to cut through a road surface and once the soil beneath the road surface has been

exposed, the operator would detach this version of the nozzle and attach the rotating

version shown in Figures 2 and 3 to excavate the soil.

The nozzle 7 shown in Figure 6 produces a stream 14 which diverges more than

the stream 13 produced by the nozzle of Figure 4 but less than the cone produced by

streams 10 and 12 of the nozzle 7 shown in Figure 2. The nozzle 7 of Figure 6 is best

suited to applications where is it necessary to commence excavating at a surface

consisting of soil. This is because the broad cutting cone provided by the nozzle shown

in figures 2 and 3 causes significant unwanted splashing of cutting fluid and detritus

when commencing excavation at the surface. This splashing is minimised by the nozzle

of figure 6 due to the narrower stream which it provides. The nozzle of Figure 6 also provides a less intense cutting stream 14 as compared to the narrow cutting stream 13

shown in Figure 4. This gives rise to a reduced likelihood that services will be

inadvertently ruptured when excavating using the nozzle 7 shown in Figure 6.

Referring to Figure 1, the suction means 5 includes a pump 15 which sucks

detritus (not shown) from the excavation site 4, along a suction hose 16 and ultimately

into a storage tank 17. When using water as the cutting fluid, the storage tank 17

includes de- watering means 18 adapted to expel at least some of the water from the

storage tank 17. The de- watering means 18 is in the form of a pipe disposed inside the

tank 17. The pipe 18 includes a plurality of holes 19 each disposed at various heights so

as to capture water within the tank 17 once the detritus has settled to the bottom 20 of the

storage tank 17. Once the waste water has passed through holes 19 it exits from the tank

17 via waste water exhaust 21.

The pressurised fluid source 2 includes a water reservoir 22 and a pump 23 which

acts upon the water from the reservoir 22 to raise it to the required pressure. In some

embodiments a single pump is adapted to both provide the raised water pressure required

for the pressure cutting fluid source 2 and the vacuum required for the suction means 5.

The console 25 includes a plurality of controls 26 to enable an operator (not

shown) to remotely control the operation of the excavating device 1. One of the controls

26 is a fluid actuator which opens or closes a valve 27 in the hose 6 to start and/or stop

the flow of cutting fluid through the outlet 3. Another of the controls 26 is operable to

adjust the suction provided by the suction means 5.

A plurality of extension pipes 28 are optionally attachable to the cutting fluid hose

6 between the console 25 and the outlet 3 to effectively allow for extension of the cutting fluid hose 6 as excavation progresses and the hole 29 increases in depth. Similar

extension pipes may be provided to lengthen the suction hose 16.

As shown in Figure 7, in another embodiment of the excavating device, a sidewall

of the cutting fluid hose 6 is attached to a sidewall of the suction hose 16 such that the

outlet 3 protrudes beyond an inlet 30 of the suction hose 16. This arrangement is more

suited to the excavation of deeper holes as compared to the arrangement shown in figure

1 wherein the cutting fluid hose 6 is separate from the suction hose 16.

In the preferred embodiment illustrated in Figure 8, the pressurised cutting fluid

source 2 and the suction means 5 are disposed upon a first truck 31. The storage tank 17

of the suction means 5 includes access means 32 to enable removal of accumulated

detritus which may be drained into a second truck (not illustrated) having a separate

storage tank. Hence the first truck 31, bearing the excavating device of the present

invention, may advantageously remain at an excavation site whilst the second truck

transports the drained detritus to a disposal site.

The truck 31 includes a boom 33 supporting a first portion 34 of the cutting fluid

hose 6 and the suction hose 16 such that a second portion 35 of the hoses is free to hang

under the influence of gravity from a distal end 36 of the boom 33. The boom 33 is

telescopic to facilitate the positioning of said second portion 35 of the hoses into a

position 37 to the excavated. The telescopic feature of the boom 33 is one aspect of

boom driving means (not illustrated) operable to control the positioning of the boom 33.

Boom driving controls 38 are provided upon the console 25 which are adapted to control

the boom driving means. In this way, a single operator with access to the console 25 can

control the positioning of the second portion 35 of the hoses, and therefore the positioning of the cutting outlet 3 and the suction inlet 30. The boom 33 is pivotally

mounted to the first truck 31. This enables another aspect of the beam driving means to

alter the angular disposition of the boom 33 with reference to the truck 31. In another

preferred embodiment (not illustrated) the hoses 6 and 16 are wound upon a spool such

that the outlet 3 and the inlet 30 are extensible or retractable together. The winding of

the spool is automated via controls upon the console which enable an operator to

remotely raise or lower the outlet 3 and inlet 30 up and/or down an excavated hole.

In another preferred embodiment, the pressurised cutting fluid source 2 is

connected to a manifold (not illustrated) which branches into a plurality of cutting fluid

hoses 6. A regulator may be included, either before or after the manifold, to regulate the

pressure of the cutting fluid. This enables a plurality of users to either simultaneously

excavate separate holes or to combine efforts to excavate a single hole more quickly.

In another embodiment illustrated in Figure 9, a camera 39 is disposed adjacent the

outlet 3. This enables a remote user to monitor the cutting and suction and is particularly

suited to deep excavation where visual monitoring of the hole from the surface may be

difficult. The camera 39 communicates via cable 40 to a remote display screen (not

illustrated). Preferably the remote display screen is disposed in close proximity to the

console 25. In this manner the material being excavated can be monitored. For

example, if, whilst excavating soil, a reef of rock is encountered, this may be viewed by

the remote operator on the display screen, and the appropriate nozzle may be attached to

the hose 6. A light source (not illustrated) is disposed either on or in proximity to the

camera 39 so as to illuminate a region viewed by the camera. As shown in Figure 10, a gantry 41 is disposable above a region to be excavated 37

and is adapted to support a first portion 34 of said fluid and suction hoses 6 and 16 and

to allow a second portion 35 of the hoses 6 and 16 to hang freely under gravity towards

the region to be excavated 37. The gantry 41 includes hose positioning means 42

operable to control the position from which the second portion 35 of the hoses hangs.

The console 25 includes hose positioning controls 43 adapted to control the hose

positioning means 42. The hose positioning means 42 includes a pair of rails 44 upon

the gantry 41. The rails 44 include tracks 45 along which an arm 46 is drivable,

preferably by electric motors (not illustrated). The arm 46 includes a second track 47

disposed generally orthogonal to the first track 45. Hose engagement means 48 are

drivable along the second track 47. In this manner, the gantry enables remote control of

the positioning of the hoses giving two degrees of freedom along axes X and Y. In

particular, the arm 46 is drivable along tracks 45 to position the hoses 35 in the Y axis

and the hose engagement means 48 is drivable along the second track 47 to position

hoses 35 in the X axis.

The preferred method for excavating according to the present invention includes

the following steps:

(a) providing a pressurised cutting fluid source 2 communicating with an outlet

3 adapted to spray cutting fluid (not illustrated);

(b) spraying cutting fluid from said outlet 3 so as to excavate material

adjacent said outlet 3; and

If necessary, the detritus may be de- watered by the de- watering means described

above and it may also be replaced into the excavated hole upon completion of the job. If services are likely to be present in the region being excavated, the step of

spraying cutting fluid from the outlet 3 to excavate material preferably includes the steps

of:

(a) visually inspecting the excavation site to spot services as they are

exposed;

(b) keeping the outlets 3 a sufficient distance from any exposed services to

avoid damaging said services;

(c) turning off the flow of cutting fluid whilst passing the outlet past the

services; and

(d) re-commencing the flow of cutting fluid once the outlet is past the

services.

Claims

Claims:

1. An excavating device including:

cutting fluid so as to excavate material adjacent said outlet; and

suction means disposed so as to suck detritus resulting from excavated material

away from said outlet.

2. An excavating device according to claim 1 wherein said cutting fluid is, or

includes, water.

3. An excavating device according to claim 1 wherein said cutting fluid is, or

includes, air.

4. An excavating device according to any one of claims 1 to 3 wherein cutting fluid

in said pressurised cutting fluid source is at a pressure of greater than 2000 psi.

5. An excavating device according to any one of claims 1 to 3 wherein cutting fluid

in said pressurised cutting fluid source is at a pressure of between 3000 psi and

40,000 psi.

6. An excavating device according to any one of claims 1 to 3 wherein cutting fluid

in said pressurised cutting fluid source is at a pressure of between 4000 psi and 20,000

psi.

7. An excavating device according to any one of the preceding claims wherein,

during use, said cutting fluid is ejected from said outlet at a rate of less than 200 litres

per minute.

8. An excavating device according to any one of the preceding claims wherein,

during use, said cutting fluid is ejected from said outlet at a rate of less than 100 litres

per minute.

9. An excavating device according to any one of the preceding claims wherein,

during use, said cutting fluid is ejected from said outlet at a rate of less than 25 litres per

minute.

10. An excavating device according to any one of the preceding claims wherein said

outlet communicates with said pressurised cutting fluid source via a cutting fluid hose.

11. An excavating device according to claim 10 wherein said outlet is a nozzle

rotatably disposed upon said cutting fluid hose.

12. An excavating device according to claim 11 wherein said nozzle includes a first

aperture being offset from an axis of rotation of said nozzle, said first aperture being

oriented such that ejection of said cutting fluid through said first aperture promotes

rotation of said nozzle such that ejected cutting fluid effectively forms a cutting cone.

13. An excavating device according to claim 12 wherein said nozzle further includes a

second aperture disposed opposite said first aperture such that said axis of rotation lies

substantially intermediate said first and second apertures, said second aperture being

oriented such that ejection of said cutting fluid through said second aperture promotes

rotation of said nozzle.

14. An excavating device according to claim 10 wherein said outlet is a nozzle fixedly

disposed upon said hose, said nozzle including a single aperture shaped to eject said

cutting fluid in a narrow stream.

15. An excavating device according to any one of claims 11 to 14 wherein said nozzle

is selectively detachable from said cutting fluid hose.

16. An excavating device according to any one of the preceding claims wherein said

suction means feeds said detritus to a storage tank.

17. An excavating device according to claim 16 wherein said fluid is water and said

storage tank includes de- watering means adapted to expel at least some of said water

from said storage tank.

18. An excavating device according to claim 17 wherein said de- watering means

includes a pipe disposed within said tank and including a plurality of holes each

disposed a various heights so as to capture water within said tank once said detritus has

settled to a bottom of the storage tank.

19. An excavating device according to any one of the preceding claims wherein said

pressurised fluid source includes a water reservoir and a pump acting upon water from

said reservoir.

20. An excavating device according to any one of the preceding claims wherein said

suction means includes a suction hose acted upon by a vacuum pump.

21. An excavating device according to any one of claims 10 to 20 further including a

fluid actuator disposed upon said hose, said actuator being operatively connected to a

valve for controlling a flow of cutting fluid through said outlet.

22. An excavating device according to claim 21 further including a plurality of

extension pipes, each optionally attachable to said cutting fluid hose between said fluid

actuator and said outlet so as to effectively allow for extension of said cutting fluid hose

as excavation progresses.

23. An excavating device according to claim 20 when depended from claim 10

wherein a sidewall of said cutting fluid hose is attached to a sidewall of said suction hose and wherein said outlet protrudes beyond an inlet of said suction hose.

24. An excavating device according to any one of the preceding claims wherein said

pressurised cutting fluid source and said suction means are both disposed upon a truck.

25. An excavating device according to claim 24 when depended from claim 16

wherein said storage tank includes access means to enable removal of accumulated

detritus.

26. An excavating device according to any one of the preceding claims wherein said

pressurised cutting fluid source is connected to a manifold branching into a plurality of

cutting fluid hoses.

27. An excavating device according to any one of the preceding claims further

including a camera disposed adjacent said outlet, said camera communicating with a

remote display screen so as to enable an operator of the excavating device to monitor

cutting and suction.

28. An excavating device according to claim 27 further including a light source

disposed so as to illuminate a region viewed by said camera.

29. An excavating device according to claim 16 further including a boom supporting a

first portion of said cutting fluid hose and said suction hose such that a second portion of

said hoses hangs freely under the influence of gravity from a distal end of the boom.

30. An excavating device according to claim 29 wherein said boom is telescopic to

facilitate the positioning of said second portion of said hoses into a position to be

excavated.

31. An excavating device according to claim 29 or 30 further including boom driving

means operable to control the positioning of said boom.

32. An excavating device according to claim 32 wherein boom driving controls

adapted to control the boom driving means are disposed upon a console which also

includes said fluid actuator.

33. An excavating device according to any one of claims 29 to 32 wherein said boom

is pivotally mounted to said first truck.

34. An excavating device according to claim 10 further including a gantry disposable

above a region to be excavated, said gantry being adapted to support a first portion of

said fluid and suction hoses such that a second portion of said hoses hangs freely under

gravity.

35. An excavating device according to claim 34 wherein said gantry includes hose

positioning means operable to control the position from which said second portion of the

hoses hangs.

36. An excavating device according to claim 35 further including hose positioning

controls adapted to control said hose positioning means, said hose positioning controls

being disposed on said console.

37. An excavating device according to claim 34 or 35 wherein said hose positioning

means include a pair of rails having a first track along which an arm is drivable.

38. An excavating device according to claim 37 wherein said arm includes a second

track disposed generally orthogonal to said first track, and wherein hose engagement

means is drivable along said second track.

39. A method of excavating including the following steps:

(a) providing a pressurised cutting fluid source communicating with an outlet

said outlet;

(c) using suction means disposed proximate said outlet to suck detritus resulting

from excavated material away from said outlet.

40. A method of excavating according to claim 39 wherein said detritus is replaced

into the excavated hole.

41. A method of excavating according to claim 39 or 40 wherein said step of spraying

cutting fluid from the outlet to excavate material includes the steps of:

(a) visually inspecting the excavation site to spot any services that may be

exposed;

(b) keeping the outlets a sufficient distance from any exposed services to avoid

damaging said services;

(c) turning off the flow of cutting fluid whilst passing the outlet past the

services.

42. An excavating device substantially as herein described with reference to any one of

the embodiments shown in the accompanying figures.

43. A method of excavating substantially as herein described with reference to any one

of the embodiments shown in the accompanying figures.