Title:
VACUUM SYSTEM WITH IMPROVED MOBILITY
Kind Code:
A1


Abstract:
A self-propelled mobile vacuum system comprising a vacuum source that provides suction for the removal of debris, a collection tank for storing debris collected by said vacuum source suction, and at least two rolling drive systems for maneuvering the vacuum system within a work space. A motor provides power to the vacuum source and the two rolling drive systems, and the system has an overall width within the range of 24 to 48 inches, an overall length within the range of 5 to 10 feet, and an overall height within the range of 60 to 84 inches.



Inventors:
Maybury, Charles Robert (Greer, SC, US)
Application Number:
11/695782
Publication Date:
10/09/2008
Filing Date:
04/03/2007
Primary Class:
International Classes:
E01H1/08; A47L5/00
View Patent Images:
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Primary Examiner:
MULLER, BRYAN R
Attorney, Agent or Firm:
Nelson Mullins Riley & Scarborough LLP (Charlotte, NC, US)
Claims:
What is claimed is:

1. A self-propelled mobile vacuum system comprising a. a frame; a vacuum pump mounted to said frame having i. a low-pressure intake port, and ii. a high-pressure outlet port; b. a collection tank mounted to said frame and in fluid communication with said low pressure intake port, said collection tank for storing debris collected by said vacuum source; c. at least two drive systems for maneuvering said mobile vacuum system into and around a work space; and d. a motor that is operatively connected to said vacuum source and said at least two drive systems; wherein said mobile vacuum system has a width of less than approximately about 36 inches for maneuvering through small openings.

2. The self-propelled mobile vacuum system of claim 1, wherein said mobile vacuum system has an overall length of approximately 8 feet and an overall height of approximately 72 inches.

3. The self-propelled mobile vacuum system of claim 1, further comprising a remote controller operatively connected to said at least two drive systems for actuating said at least two drive systems.

4. The self-propelled mobile vacuum system of claim 1, said at least two drive systems each further comprising a plurality of wheels.

5. The self-propelled mobile vacuum system of claim 1, said at least two drive systems each further comprising a tank tread.

6. The self-propelled mobile vacuum system of claim 5, wherein each tank tread operates independently of the other.

7. The self-propelled mobile vacuum system of claim 1, wherein said motor is a hydraulic motor.

8. The self-propelled mobile vacuum system of claim 1, wherein said collection tank is mounted at an angle of between approximately 30-60 degrees with respect to said frame.

9. The self-propelled mobile vacuum system of claim 8, wherein said collection tank is mounted at an angle of between approximately 35-45 degrees with respect to said frame.

10. A self-propelled mobile vacuum system comprising a. a frame; b. a vacuum pump mounted on said frame and having i. a low-pressure intake port, and ii. a high-pressure outlet port; c. a collection tank mounted on said frame at an angle of between approximately 30-60 degrees with respect to said frame, said collection tank being in fluid communication with said vacuum pump low pressure intake port; d. at least two moveable treads operatively coupled to said frame and moveable with respect to said frame; e. a water pump mounted on said frame; and f. a hydraulic motor mounted on said frame and operatively connected to said vacuum pump, said water pump and said at least two moveable treads wherein said mobile vacuum system has a width within the range of approximately 24 to 48 inches, a length within the range of approximately 5 to 10 feet, and a height within the range of approximately 60 to 84 inches.

11. The self-propelled mobile vacuum system of claim 10, further comprising a remote control operatively connected to said at least two moveable treads.

12. The self-propelled mobile vacuum system of claim 10, wherein said remote control varies the hydraulic pressure delivered to each of said at least two moveable tank treads.

13. The self-propelled mobile vacuum system of claim 10, wherein said vacuum system has an overall width of approximately 36 inches, an overall length of approximately 8 feet, and an overall height of approximately 72 inches.

14. The self-propelled mobile vacuum system of claim 10, further comprising a cyclone separator mounted intermediate said vacuum pump and said collection tank.

15. A self-propelled mobile vacuum system comprising a. a frame; b. a collection tank coupled to said frame and having i. a first low-pressure intake port, and iii. a first high-pressure outlet port; b. a vacuum pump coupled to said frame and having i. a second low-pressure intake port operatively connected to said first high-pressure outlet port, and ii. a second high-pressure outlet port; c. a tool detachably connected to said collection tank first low pressure intake port for channeling debris into said collection tank; d. a drive system operatively mounted to said frame for maneuvering said mobile vacuum system into and around a work space; e. a motor operatively coupled to said vacuum pump and said drive system for powering said vacuum pump and said drive system; and f. a wireless remote control operatively coupled to said motor, said vacuum pump and said drive system for independently controlling each of said motor, said vacuum pump and said drive system, wherein said self-propelled vacuum system has a width within the range of approximately 24 to 48 inches, a length within the range of approximately 5 to 10 feet, and a height within the range of approximately 60 to 84 inches.

16. The self-propelled mobile vacuum system of claim 15 wherein said motor is a hydraulic motor.

17. The self-propelled mobile vacuum system of claim 16 wherein each of said drive system further comprises at least two hydraulic-powered tank treads.

18. The self-propelled mobile vacuum system of claim 16, wherein said drive system is a hydraulic-powered wheel set.

19. The self-propelled mobile vacuum system of claim 9, wherein a. said collection tank defines a longitudinal axis; b. said frame defines a horizontal plane; and c. said collection tank is mounted to said frame so that said collection tank longitudinal axis is disposed at an angle to said frame plane of at least approximately 20 degrees.

Description:

FIELD OF THE INVENTION

This invention relates generally to an earth reduction vacuum system for removing soil to expose underground utilities (such as electrical and cable services, water and sewage services, etc.), and more particularly to a vacuum system with improved mobility.

BACKGROUND OF THE INVENTION

With the increased use of underground utilities, it has become more critical to locate and verify the placement of buried utilities before performing digging or excavation work. If the location of a buried utility is unknown, the use of conventional digging and excavation methods such as shovels, post hole diggers, powered excavators, and backhoes can cut, break, or otherwise damage the lines during excavation.

Devices have been previously developed to create holes in the ground to non-destructively expose underground utilities to view. One design uses high pressure air delivered through a tool to loosen soil and a vacuum system to vacuum away the dirt after it is loosened to form a hole. Another system uses high pressure water delivered by a tool to soften the soil and create a soil/water slurry mixture. The tool is connected with a vacuum system for vacuuming the slurry away from the utility and into a collection tank. The tank may then be emptied by opening a door on the tank.

Prior art vacuum systems are typically very large and heavy, and therefore must be mounted onto the bed of a carrier vehicle such as a heavy duty truck or trailer. One disadvantage of such prior art vacuum systems is that the work space must be large enough to accommodate the size of the system and its carrier vehicle. When working in small areas or areas with access points too small for a large vehicle, it may be impossible to position both the vacuum system and the vehicle in close proximity to the work area.

SUMMARY OF THE INVENTION

The present invention recognizes and addresses disadvantages of prior art constructions and methods, and it is an object of the present invention to provide a self-propelled mobile vacuum system comprising a vacuum source that provides suction for the removal of debris, a collection tank for storing debris collected by the vacuum source, and at least two rolling drive systems for maneuvering the vacuum system within a work space. A motor provides power to the vacuum source and the two rolling drive systems, and the system is sized appropriately to pass through a standard residential fence gate having a opening width of about 36 inches.

In another embodiment, a self-propelled mobile vacuum system comprising a vacuum source that provides suction for the removal of debris, a collection tank for storing debris collected by the vacuum source, and at least two rolling drive systems for maneuvering the vacuum system within a work space. A motor provides power to the vacuum source and the two rolling drive systems, and the system has an overall width within the range of 24 to 48 inches, an overall length within the range of 5 to 10 feet, and an overall height within the range of 60 to 84 inches.

In still another embodiment, a self-propelled mobile vacuum system comprises a collection tank with a first low-pressure intake port and a first high-pressure port defined though the collection tank's external wall. A vacuum source with a second low-pressure intake port is operatively connected to the first high-pressure outlet port and creates a low-pressure condition inside the collection tank relative to ambient air pressure. The system also includes an elongated suction implement detachably connected to the first low pressure intake port for channeling debris into the collection tank, at least two rolling drive systems for maneuvering the mobile vacuum system within a work space, a motor providing power to the vacuum source and rolling drive systems; and a remote control used by an operator to direct the motion of the rolling drive systems when maneuvering said mobile vacuum system within the work place. The mobile vacuum system has an overall width within the range of 24 to 48 inches, an overall length within the range of 5 to 10 feet, and an overall height within the range of 60 to 84 inches.

BRIEF DESCRIPTION OF THE DRAWINGS

A full and enabling disclosure of the present invention, including the best mode thereof directed to one of ordinary skill in the art, is set forth in the specification, which makes reference to the appended figures, in which:

FIG. 1 is a perspective view of a mobile vacuum system in accordance with the present invention;

FIG. 2 is a side view of the mobile vacuum system of FIG. 1;

FIG. 3 is a perspective view of the mobile vacuum system of FIG. 1;

FIG. 4 is an a perspective view of a earth reduction tool for use with the mobile vacuum system of FIG. 1;

FIG. 5 is bottom perspective view of the earth reduction tool shown in FIG. 4;

FIG. 6 is a partial exploded perspective view of the earth reduction tool of FIG. 5;

FIG. 7 is partial perspective view of the earth reduction tool of FIG. 4 in use digging a hole;

FIG. 8 is a side plan view of the earth reduction tool of FIG. 4;

FIG. 9 is a top plan view of the earth reduction tool of FIG. 4;

FIG. 10 is a bottom plan view of the earth reduction tool of FIG. 4;

FIG. 11 is a side section view of the earth reduction tool of FIG. 9 taken along lines 1-11;

FIG. 12 is a perspective view of the earth reduction tool of FIG. 4 in use with the mobile vacuum system of FIG. 1;

FIG. 13 is a schematic view of the hydraulic, electric, water, and vacuum systems of the mobile vacuum unit of FIG. 1; and

FIG. 14 is a perspective view of the mobile vacuum unit of FIG. 1 in use.

Repeat use of reference characters in the present specification and drawings is intended to represent same or analogous features or elements of the invention.

DETAILED DESCRIPTION

Reference will now be made in detail to presently preferred embodiments of the invention, one or more examples of which are illustrated in the accompanying drawings. Each example is provided by way of explanation of the invention, not limitation of the invention. In fact, it will be apparent to those skilled in the art that modifications and variations can be made in the present invention without departing from the scope and spirit thereof. For instance, features illustrated or described as part of one embodiment may be used on another embodiment to yield a still further embodiment. Thus, it is intended that the present invention covers such modifications and variations as come within the scope of the appended claims and their equivalents.

Referring to FIG. 1, 2 and 3, a mobile earth reduction system 10 generally includes a chassis 12 having a front end 14 and a rear end 16, a collection tank 18 located proximate to chassis rear end 16, a motor 20 located proximate to chassis front end 14, and a water reservoir tank 22 located between the motor and the collection tank. In a preferred embodiment, chassis 12 includes two hydraulically-operated tank treads 24A and 24B (FIGS. 1 and 3) which allow easy maneuverability and transportation of the mobile earth reduction system. It should be understood that wheels may be substituted for the tank treads, and the components of the drilling system may be either directly mounted to the chassis or indirectly mounted to the chassis through connections with other system components. Preferably, treads 24A and 24B are spaced apart at a distance within the range of about 24 to 48 inches or less to minimize the overall width of the mobile earth reduction system. Additionally, the digging system preferably has an overall length of less than approximately 10 feet and an overall height of less than approximately 84 inches. Most preferably, the mobile earth reduction system has a width of 36 inches, a length of 8 feet and a height of 72 inches so that the system will pass through a standard residential fence gate (not shown) without requiring an operator 5 (FIGS. 12 and 14) to remove sections of the fencing.

Motor 20 is mounted to a frame 26 attached to chassis front end 14 and has an output shaft (not shown) that drives a hydraulic pump 30 as shown in FIG. 13. The motor output shaft is also connected to a water pump 32 (FIG. 2) and a vacuum pump 34 by a series of vee-belts (not shown). It should be understood that alternative power transmission systems, such as chains or gear drives, may be substituted for the vee-belts to connect the motor output shaft to the water and vacuum pumps. Motor 20 is preferably a gas or diesel engine, although it should be understood that an electric motor or other motive means could also be used. In one preferred embodiment, motor 20 is a twenty-four horsepower gasoline engine, such as Model No. GX670 manufactured by the Honda Power Equipment division of the American Honda Motor Company. A muffler 36 is attached to the exhaust header (not shown) of the motor to reduce the motor's exhaust noise. Frame 26 supports vacuum pump 34, a storage bin 38, and two rigging shackles 40A and 40B (FIG. 3) that provide connection points for lifting or tie-down rigging used to secure the digging system during transportation on a trailer or in the bed of a truck.

A battery box 42 (FIGS. 2 and 3) mounted to frame 26 beneath motor 20 houses a battery (not shown) that provides electrical power for the motor, control switches and any auxiliary equipment requiring electricity. A tool box 44 attached to chassis 12 on one side of the water reservoir houses digging and cutting implements and other tools.

Referring now to FIGS. 2 and 3, a fuel tank 46 located aft of water reservoir tank 22 directly beneath collection tank 18, supplies fuel to motor 20 through a fuel line (not shown). A control box 50, located aft of motor 20, houses a number of switches 52 (FIG. 3) that control onboard functions such as overriding the collection tank float sensor and activating water pump 32 (FIG. 2) as described in further detail below.

Referring back to FIGS. 1-3, collection tank 18 is secured to chassis 12 by a first mounting bracket 60 positioned at chassis rear end 16 and a second mounting bracket 62 positioned proximate to water reservoir tank 22. First bracket 60 is shorter than second bracket 62 and has a first brace 61A equipped with a rigging shackle 63A (FIGS. 1 and 2) and a second brace 61B equipped with a rigging shackle 63B (FIG. 3). Because of the relative height of first mounting bracket 60 and second mounting bracket 62, the two mounting brackets position tank 18 at an angle of about 45 degrees with respect to chassis 12.

Referring to FIGS. 1 and 2, collection tank 18 has a discharge door 64 pivotally attached to the tank by a hinge 66 that rotates the door into and away from engagement with a sealing flange 70 on collection tank 18. Discharge door 64 has a locking mechanism (not shown) operated by a locking handle 68. When the door is closed against sealing flange 70, the operator may rotate locking handle 68, which engages the locking mechanism and seals the door against tank sealing flange 70. The discharge door also has a gate valve 72 that allows the operator to drain water or other fluids from collection tank 18 without having to unseal and open door 64.

Referring to FIG. 13, water reservoir tank 22 connects to water pump 32, which includes a low pressure inlet 80 and a high pressure outlet 82. In the illustrated embodiment, water pump 32 can be any of a variety of suitable pumps that delivers between 500 and 3,000 lbs/in2 at a flow rate of approximately two to four gallons per minute. In one preferred embodiment, water pump 32 is a Model No. TX1512 pump manufactured by General Pump of Mendota Heights, Minnesota equipped with a clutch (not shown), preferably a model 10078 clutch also manufactured by General Pump. Water tank 22 is preferably formed from polypropylene and has an outlet 84 that connects to a strainer 86 through a valve 88. The output of strainer 86 connects to the low pressure side of water pump 32 via a hose 90. A check valve 92 is placed inline intermediate strainer 86 and low pressure inlet 80. High pressure outlet 82 connects to a filter 94 and then to a pressure relief and bypass valve 96.

In a preferred embodiment, a “T” 98 and a valve 100, located intermediate valve 96 and filter 94, connect the pump high pressure output 82 to a plurality of clean out nozzles 102 mounted in collection tank 18 to clean the tank's interior, but it should be understood that the mobile vacuum system will function properly if the clean out nozzle apparatus is omitted. A return line 104 connects a low pressure port 106 of valve 96 to water tank 22. Thus, when a predetermined water pressure is exceeded in valve 96, water is diverted through low pressure port 106 and line 104 to tank 22. A hose 108, stored on a hose reel (not shown), connects an output port 110 of valve 96 to a valve 112 on a digging tool 114 (FIG. 4). A valve control 116 (FIG. 4) at a handle 118 of digging tool 114 provides the operator with a means to selectively actuate valve 112 on digging tool 114. The valve delivers a high pressure stream of water through a conduit 120 attached to an exterior of an elongated pipe 122 that extends the length of digging tool 114.

Referring to FIG. 4, digging tool 114 includes handle 118 for operator 5 (FIG. 12) to grasp during use of the tool, a head 124, and an elongated pipe 122 that connects handle 118 to head 124. A connector 126, such as a “banjo” type connector located proximate to handle 118, connects the vacuum system on mobile earth reduction system 10 (FIG. 1) to a central vacuum passage 128 (FIG. 5) in digging tool 114. It should be understood that other types of connectors may be used in place of “banjo” connector 126, for example clamps, clips, or threaded ends on hose 130 and handle 118. Referring to FIGS. 8 and 11, vacuum passage 128 extends the length of elongated pipe 122 and connects at an end (not shown) to one end of a vacuum hose 130 (FIG. 12). The other end of hose 130 connects to an inlet port 200 (FIG. 3) on collection tank 18. Referring to FIG. 6, a second end 128a of vacuum passage 128 is located proximate to an end 158 of digging tool head 124.

Referring to FIGS. 5 and 6, a fluid manifold 136, located at one end 138 of head 124, connects a water conduit 120 to a water feed line 140 formed through head 124. In one embodiment, water feed line 140 is integrally formed in the head during casting of the head. However, it should be understood that the water feed line may also be added to the head after the head is cast. Head 124 contains two sets of a plurality of nozzles 142 and 144, the first set 142 being angled radially inwardly at approximately 45 degrees from a vertical axis of the digging tool, and the second set 144 being directed parallel to the axis of the digging tool. It should be understood that the angle of first set 142 may be adjusted depending on the application of the digging tool to almost any angle between 0 and 90 degrees to enhance the digging effect of the tool.

Each nozzle is set in a countersunk hole 146 formed in a bottom surface 148 of head 124 such that the end of each nozzle is recessed from bottom surface 148. During the manufacture of a head that includes an integrally cast feed line 140, a plurality of tap holes 150 (FIG. 6) may be drilled into bottom surface 148 so that the holes tap into water feed line 140. Next, each countersunk hole 146 may be concentrically formed with each tap hole 150. Preferably, tap holes 150 have screw threads so that the nozzles may be threadedly attached to the tap holes and communicate with the water feed line.

During use of drilling tool 114, nozzles 142 and 144 produce a spiral cutting action that breaks the soil up sufficiently to minimize clogging of large chunks of soil within vacuum passage 128 and/or vacuum hose 130. Vertically downward pointing nozzles 144 enhance the cutting action of the drilling tool by allowing for soil to be removed not only above a buried utility, but in certain cases from around the entire periphery of the utility. In other words, the soil is removed above the utility, from around the sides of the utility, and from beneath the utility. This can be useful for further verifying the precise utility needing service and, if necessary, making repairs to or tying into the utility.

Still referring to FIGS. 5 and 6, an air feed passage 152 is formed in head 124 and has a first opening 154 at head end 138 and a second opening 156 at head second end 158. In one preferred embodiment, air feed passage 152 is integrally formed in the head when it is cast. However, it should be understood that the air feed may also be formed from tubing extending between head ends 138 and 158. In one preferred embodiment, second opening 156 is located at or tangential to bottom surface 148 and may be formed as a single opening or as multiple openings.

In some embodiments, head 124 may be integrally formed with elongated pipe 122, and air feed passage first opening 154 may be located anywhere along the length of the elongated pipe, provided the air feed passage first opening is located at a position distal from head second end 158. Thus, it should be understood that head 124, whether separate from or integral with elongated pipe 122, is considered to be a part of the elongated pipe. For purposes of this discussion, distal from the head second end may refer to a position anywhere from several inches away from the head second end to a point proximate the elongated body first end. What should be understood by those of skill in the art is that air intake opening 154 should not be located at any point along head 124 or elongated pipe 122 that would be covered by the material to be removed by the digging tool. It should also be understood in that some embodiments, digging tool 114 may not come equipped with a water feed system.

Referring to FIG. 12, digging tool 114 may also include a control 160 for controlling the tool's vacuum feature. Control 160 may be an electrical switch, a vacuum or pneumatic switch, a wireless switch, or any other suitable control to adjust the vacuum action by allowing the vacuum to be shut off or otherwise modulated. An antifreeze system (not shown) may be provided to prevent freezing of the water pump and the water system. Thus, when the pump is to be left unused in cold weather, water pump 32 (FIGS. 2 and 20) may draw antifreeze from the antifreeze reservoir (not shown) through the components of the water system to prevent water in the hoses from freezing and damaging the system.

Referring again to FIGS. 1, 2, 3 and 13, vacuum pump 34 is preferably a positive displacement type vacuum pump. In one preferred embodiment, vacuum pump 34 is a Model 49URAI-DSL blower manufactured by Roots Blower Division of Dresser Roots, of Tex. Vacuum pump 34 has a low pressure intake port 170 and a high pressure outlet port 172 fitted with a silencer 174 that reduces the noise associated with the air forced out of the vacuum pump outlet port. Silencer 174 may be a Model TS30TR Cowl silencer manufactured by Phillips and Temro Industries of Canada. Vacuum pump intake port 170 is fitted with a vacuum relief device 176, which may be any suitable vacuum valve, such as a Model 215V-H01AQE spring loaded valve manufactured by Kunkle Valve Division, Black Mountain, N.C. Vacuum relief device 176 controls the maximum negative pressure of the vacuum pulled by pump 34, which is in the range of between 10 and 15 inches of Mercury (Hg) in the illustrated embodiment.

Referring to FIG. 1, a blower pipe 178 connects vacuum relief device 176 with an air filter 180, located upstream of pressure relief device 176, that filters the vacuum air stream before it passes through vacuum pump 34. In one preferred embodiment, the filter media may be a paper filter such as a FleetGuard filter manufactured by Cummings Filtration. Air filter 180 has an outlet port 182 that receives blower pipe 178 and an intake port 184 that receives a separator pipe 186. The separator pipe connects air filter intake port 184 with an upstream outlet port 188 of a cyclonic separator 190. The cyclonic separator has a hopper 192 and an inlet port 194 that receives an exhaust pipe 196 that connects with an exhaust port 198 on collection tank 18.

The vacuum air stream pulled through vacuum pump 34 produces a vacuum in collection tank 18 that draws a vacuum air stream through a collection tank inlet port 200. When inlet port 200 is not closed off by a plug 202 (FIGS. 1 and 3), the inlet may be connected to hose 130 leading to digging tool 114 (FIG. 12). Thus, the vacuum air stream at inlet 200 is ultimately pulled through the tool's vacuum passage. Because it is undesirable to draw dirt or other particulate matter through the vacuum pump, a baffle system, for example as described in U.S. Pat. No. 6,470,605 (the entire disclosure which is incorporated herein), may be provided within collection tank 18 to separate the slurry mixture from the vacuum air stream. Dirt, rocks, and other debris in the air flow hit a baffle (not shown) and fall to the bottom portion of the collection tank. The vacuum air stream, after contacting the baffle, continues upwardly and exits through outlet 198, entering cyclone separator 190. The vacuum air stream then continues through filter 180, blower pipe 178 and on to vacuum pump 34.

Referring again to FIGS. 1 and 2, collection tank 18 includes a discharge door 64 connected to the main tank body by hinge 66 that allows the door to swing open, thereby providing access to the tank's interior for cleaning. Gate valve 72 may be opened to allow the liquid portion of the slurry in tank 18 to drain out without requiring the door to be opened. Gate valve 72 may also be used to introduce air into collection tank 18 to reduce the vacuum in the tank so that the door may be opened.

Referring again to FIG. 13, a preferred embodiment of the mobile vacuum unit includes clean out nozzles 102 (FIG. 13) positioned along the interior of collection tank 18. Nozzles 102 are attached to a nozzle pipe 103 that communicates with water tank 22 when valve 100 is opened and delivers high pressure water from pump 32 to nozzles 102 for producing a vigorous cleaning action in the tank. When the nozzles are not being used for cleaning, a small amount of water may be allowed to continuously drip through the nozzles to pressurize them so as to prevent dirt and slurry from entering and clogging the nozzles.

Nozzle pipe 103, apart from being a conduit for delivering water, is also a structural member that includes a threaded male portion (not shown) on an end thereof adjacent discharge door 64. When discharge door 64 is shut, screw-down type handle 68 mounted in the door is turned causing a threaded female portion (not shown) on pie 103 to mate with the male portion. This configuration causes the door to be pulled tightly against collection tank sealing flange 70 (FIGS. 1 and 2). Actuation of vacuum pump 34 further assists the sealing of the door against the tank opening.

In a preferred embodiment, operation of motor 20 provides power to a hydraulic drive system 400 through an input shaft (not shown) of hydraulic pump 30. It should be understood that the motor output shaft (not shown) and the pump input shaft may be connected by any suitable alternative power transmission mechanism, such as a vee-belt, a chain, or a gear set. In one preferred embodiment, hydraulic pump 30 is a model 26004-RZC gear pump manufactured by the Eaton Hydraulics division of Eaton Fluid Power Group of Cleveland, Ohio. Pump 30 pressurizes hydraulic oil that energizes a first and a second hydraulic motor 416 and 418 as described in further detail below. Pump 30 has a low pressure inlet port 420 connected by a suction line 422 to a hydraulic oil reservoir 424 that holds between 15 and 20 gallons of hydraulic oil. Pump 30 also has a high pressure outlet port 426 that is connected by a supply line 428 to the inlet port (not shown) of a hydraulic manifold 430. Hydraulic manifold 430 also has an exhaust port (not shown) connected to reservoir 424 by a return line 432. Preferably, manifold 430 has three solenoid valves (not shown) that selectively direct the flow of pressurized hydraulic oil through motor supply lines 434A, 434B, 434C, and 434D to hydraulic motors 416 and 418 in response to the operator's manipulation of a remote controller 436 (FIG. 14).

Referring to FIG. 14, operator 5 may maneuver mobile earth reduction system 10 into a work space by operating a remote controller 436. Controller 436 has an operator interface 438 that controls the movements of mobile earth reduction system 10. In one preferred embodiment, remote controller 436 is a radio frequency transmitter model T60RX-08ASL manufactured by Cervis, Inc. of Harmony, Pa. As operator 5 directs the movement of mobile earth reduction system 10 by switches and buttons on remote controller 436, the controller transmits radio frequency signals to a receiver 440, preferably a model T60RX-08STL also manufactured by Cervis, Inc. Receiver 440 sends control signals to the solenoid valves in manifold 430 (FIG. 13), and the opening and closing of the solenoid valves directs pressurized hydraulic oil in the appropriate direction and flow rates to hydraulic motors 416 and 418 (FIG. 13). Accordingly, the hydraulic motors activate to move tank treads 24A and 24B together or independently in the forward or reverse directions. It should be understood that a pigtail controller that communicates with control box 50 could be substituted for the radio frequency transmitter and receiver to direct the movement of the system's tank treads.

Referring to FIG. 4, once the operator maneuvers the mobile earth reduction system into the proper position within the work space to perform the desired drilling operation, the operator connects vacuum hose 130 to digging tool handle 118 using banjo connector 126. High pressure water hose 108 is also connected to valve 112 to provide water from supply tank 22 to the digging tool as shown in FIG. 13. As tool 114 is used to dig a hole, it is pressed downwardly into the ground. For larger diameter holes, digging tool 114 is moved in a generally circular manner as it is pressed downward thereby removing material from a large cross-section area. Water flows out of nozzles 142 and 144 creating a water and soil slurry formed that is then vacuumed by tool 114 through vacuum passage 128 (FIGS. 5 and 6) and accumulated in collection tank 18 (FIGS. 1, 2 and 3). Once the hole is completed and the utility exposed, the vacuum system can be shut down, and the operator may examine or repair the utility as needed.

Referring to FIGS. 1 and 13, mobile earth reduction system 10 can be used to dig multiple holes before having to empty collection tank 18. However, once collection tank 18 is full, it can be emptied at an appropriate dump site. In emptying collection tank 18 of a preferred embodiment of the mobile earth reduction system, motor 20 is idled to maintain a vacuum in the collection tank. This allows door handle 68 (FIG. 1) to be turned so that the female threaded member (not shown) is no longer in threading engagement with the male member (not shown) on nozzle pipe 103 (FIG. 13), while the vacuum pressure continuing to hold door 64 (FIG. 1) closed. Once motor 20 is shut down, the vacuum pressure is released and ambient air enters the tank, thereby pressurizing the tank and allowing the door to be opened. The inclined attitude of tank 18 allows door 64 to easily swing open to a vertical position so the slurry simply runs out of the collection tank.

It should be appreciated by those skilled in the art that various modifications and variations can be made in the present invention without departing from the scope and spirit of the invention. It is intended that the present invention cover such modifications and variations as come within the scope and spirit of the appended claims and their equivalents.