The present disclosure describes a vacuum-excavation apparatus that is connectible to a vehicle. The vacuum-excavation apparatus comprises a vacuum tube with an input end; a vacuum assembly for generating a suction force at the input end and drawing a stream of fluidized debris-material into the vacuum tube. The apparatus also includes a boom assembly for supporting the vacuum tube and a tank for receiving the stream of fluidized debris-material from the vacuum tube. The tank provides a boom mount for pivotally connecting the boom assembly and for providing fluid communication between the vacuum tube and the tank. The apparatus also includes an evacuation tube for providing fluid communication between the tank and the vacuum assembly and for distributing at least a portion of stress-loads that are generated by the boom assembly.

TECHNICAL FIELD

This disclosure generally relates to excavation. In particular, the disclosure relates to an apparatus for vacuum-excavation.

BACKGROUND

Vacuum excavation uses pressurized streams of fluids to dig a hole, a pit, a trench or a trough by loosening debris material such as soil, rocks and other materials. The loosened debris-materials are then pneumatically collected and removed by a vacuum system. Vacuum excavation can expose buried facilities without the risk of damage that may arise by digging with shovels or other heavy equipment.

Typically, vacuum-excavation apparatuses are transported upon large vehicles, such as trucks. The trucks can carry liquid-pressurization or pneumatic equipment, vacuum equipment and large tanks for containing the excavated soil, rocks and other materials. Booms are typically connected to the top of the tanks to connect a vacuum hose to the tank. The boom allows the user to move an input end of the vacuum hose about the truck during excavation operations. Due to the weight of this equipment, the mass of the excavated materials and the stress loads imparted by moving the swing boom about, the tanks are typically made up of steel with ¼ inch to ½ inch thick walls. A stress load may also be referred to as a mechanical stress. Furthermore, many tanks have thick walls or further physical reinforcements, such as extension members, that are connected to the tank to accommodate the stress loads imparted upon the tank by the moving boom. In other examples of vacuum trucks, the swing boom can have a separate support-structure that connects the swing boom directly to the vacuum truck.

In order to accommodate the weight associated with the tanks and the further physical reinforcements or separate support-structure, a typical vacuum-truck has two or three rear-axles. While the trucks with multiple rear-axles can support the weight of the vacuum-excavation apparatus and can carry heavy loads of debris materials within the tank, these trucks have limited maneuverability, low fuel-efficiency and can cause damage to roadways. Furthermore, many jurisdictions require a specialized operator's license to operate trucks with multiple rear-axles.

SUMMARY

Some embodiments of the present disclosure relate to a vacuum-excavation apparatus. The apparatus comprises a vacuum assembly, a tank and a boom assembly that is pivotally connectible to the tank by a boom mount. The boom mount is coupled to the tank, for example by one or more support members. The tank further comprises an evacuation pipe that is coupled to the boom mount and coupled to the tank, for example by one or more further support members. The evacuation pipe is in fluid communication with the interior of the tank and it directs the evacuation fluid towards a vacuum assembly that is downstream of the tank.

Some embodiments of the present disclosure relate to a tank for use with a vacuum-excavation apparatus. The tank comprises a boom mount that is coupled to the tank, for example by one or more support members. The tank further comprises an evacuation pipe that is coupled to the boom mount and to the tank by one or more further support members. The evacuation pipe is in fluid communication with the interior of the tank and it is configured to direct an evacuation fluid stream towards a vacuum assembly that is downstream of the tank. The evacuation pipe and the one or more further supports are configured to assist in distributing stress-loads that are imparted upon the boom mount and the tank by a boom assembly, or movement thereof, that is connected to the boom mount. A stress load may also be referred to herein as a mechanical stress.

Without being bound by any particular theory, the inventors have found that coupling the boom mount to either or both of the rear header of the tank and the evacuation pipe distributes at least a portion of the stress loads imparted by the boom-assembly. In particular, at least a portion of the stress-loads are distributed areas where the support members are coupled to the rear header. The stress-loads are also distributed to the where each of the further support members are coupled to the tank. Due to this distribution of at least a portion of the stress loads, some or all of the tank can be made with a thinner wall. Thinner tank walls decreases the overall weight of the tank as compared to a typical vacuum-truck tank. Distributing at least a portion of the stress loads avoids the necessity of further boom-supporting structures, which also decreases the overall weight of the vacuum-evacuation apparatus as compared to a typical vacuum-truck tank. Furthermore, further fluid conduction members between the tank and the vacuum assembly are not necessary, which also decreases the overall weight of the vacuum-excavation apparatus. These features contribute towards a vacuum-excavation apparatus that is light enough to be supported by a vehicle with a single rear-axle chassis.

DETAILED DESCRIPTION

Embodiments of the present disclosure will now be described by reference toFIG. 1toFIG. 5, which show representations of a vacuum-excavation apparatus.

FIG. 1shows a vehicle10that can support one embodiment of the present disclosure that relates to a vacuum-excavation apparatus11. The vacuum-evacuation apparatus11comprises various components including a boom assembly18, a tank30and a vacuum assembly38. The vehicle10may be a truck with a chassis that has one or more rear-axles. In some embodiments of the present disclosure, the truck10has a single rear-axle.

The boom assembly18comprises a vacuum tube20and a support arm24. The vacuum tube20has an input end22that is in fluid communication with other sections of the vacuum-excavation apparatus11. The support arm24is pivotally connectible to the tank30. The support arm24supports the vacuum tube20so that the input end22can be positioned adjacent material to be excavated during excavation operations in the vicinity of the vehicle10. As described further below, the input end22is fluidly connected to the vacuum assembly38so that during excavation operations materials such as rocks, soil, ice and other debris, collectively debris materials, are fluidized, sucked into the input end22and conducted to other sections of the vacuum-excavation apparatus11. In some embodiments of the present disclosure the boom assembly18weighs between about 550 pounds and about 650 pounds (one pound is equivalent to about 0.454 kilograms). During excavation operations when debris material is conducted through the vacuum tube20, the boom assembly18may impart loads of up to 1100 pounds, which may be inclusive of any operator contribution that occur during excavation operations. In some embodiments of the present disclosure the boom assembly18may also be extendible and retractable to increase the distance that the input end22can reach. The support arm24may have a retracted length of about 10 feet and an extended length of about 18 feet. In some embodiments of the present disclosure, the support arm24has a retracted length of about 12 feet and an extended length of about 16 feet. The boom assembly18and movement thereof impart stress loads on the tank30. A stress load may also be referred to herein as a mechanical stress. As will be discussed further below, embodiments of the present disclosure distribute at least a portion of these stress-loads to various structures and locations of the tank30. This distribution of at least a portion of the stress loads allows the tank30to be constructed of less material and, therefore, to have a lighter overall weight.

FIG. 2shows one embodiment according to the present disclosure that relates to the tank30. The tank30is made up of one or more walls made of a rigid material, for example A36 steel, high-strength steel and aluminium. The tank30comprises a front header32, a middle section33and a rear header34all of which define a tank space30A therein. The front header32and the rear header34define a longitudinal axis of the tank30, shown as X inFIG. 2andFIG. 3A. The tank30also has a lower surface31and an upper surface35.

In some embodiments of the present disclosure, the front header32defines an access port62. The access port62provides access into the tank space30A, which may be useful for cleaning or maintenance of the tank30. The access port62may be covered by a releasably sealable door (not shown). In some embodiments of the present disclosure the rear header34defines one or more ports therethrough. For example, the rear header34may define a debris port (not shown) with a debris chute66and a releasably sealable debris-chute door66A. The rear header34may also define an ancillary port68that is covered by a releasably sealable door (not shown). The ancillary port68may be used for visual inspection of the tank space30A and/or to connect further tubes or pipes to the tank30. The lower surface31may define one or more drain holes (not shown) each of which may be covered by a drain valve60. The lower surface31may also include one or more mounting rails62for connecting the tank30to the vehicle10.

In some embodiments of the present disclosure the front header32and the rear header34have a thickness between about ⅛ of an inch and about ½ of an inch (an inch is equivalent to about 0.0254 meters). In some embodiments of the present disclosure the middle section33has a thickness between about 1/16 of an inch and about 5/16 of an inch. In some preferred embodiments of the present disclosure the front header32and the rear header34have a thickness that is about ¼ of an inch and the middle section33has a thickness that about 3/16 of an inch thick. In these preferred embodiments of the present disclosure the tank may weigh about 3500 pounds. Decreasing the thickness of the middle section from ¼ of an inch to 3/16 of an inch may result in a decrease of about 400 pounds in total tank weight. A comparative tank that has a front header, a rear header and a middle section that all have a thickness of ½ of an inch weighs about 2400 pounds more than the preferred embodiments of the tank30described herein, with other dimensions and materials being substantially similar.

FIG. 3AandFIG. 3Bshow an upper portion of some embodiments of the tank30. The boom mount28extends upwardly from the upper surface35. In some embodiments of the present disclosure the boom mount28is coupled to the upper surface35of the tank30. As referred to herein, the terms “couple” and “coupling” may refer to the manner by which two components of the vacuum-excavation apparatus11can be physically joined together so that stress loads may be distributed between the coupled components or from one to the other. For example, coupling may occur by welding that provides a weld-bead height that is the same as or close to the thickness of the two components that are being coupled together. In some embodiments of the present disclosure, the two components that are being coupled together are not the same thickness, in which case the weld-bead height may be the same or close to the thickness of the thinner component, or not. For example, in some embodiments of the present disclosure, a weld-bead height of about ⅛ of an inch to about ½ of an inch is suitable for coupling, as described herein. In further embodiments of the present disclosure, a weld-bead height of about ¼ of an inch is suitable for coupling, as described herein. The boom mount28defines a boom mount aperture28A that provides fluid communication through the upper surface35to the tank space30A therebelow (seeFIG. 3B). In the embodiment shownFIG. 3, the boom mount28has a mounting flange26. The mounting flange26is connectible to the boom assembly18via one or more connection members (not shown) and the pivoting capability of the boom assembly18is achieved by the support arm24including a pivot member. However, as will be appreciated by those skilled in the art, the boom mount28may connect with the boom assembly18in various manners that don't require a mounting flange26but still permit pivoting movement of a connected boom assembly18. In some embodiments of the present disclosure the boom assembly18may pivot by rotating about an axis that is substantially perpendicular to the longitudinal axis X of the tank30. For example, the boom assembly18may rotate along a first plane that is substantially parallel to a rear axle of the truck10with about 300 to about 340 degrees of rotational freedom, when viewed from above. In some embodiments of the present disclosure the boom assembly18may also rotate above and below the first plane by about 30 degrees.

The boom mount28is coupled to the rear header34by one or more supporting members50. In some embodiments the one or more supporting members50are coupled to both of the boom mount29and the rear header34. The one or more supporting members50can also be referred to as struts or gussets. In the embodiment depicted in the appended figures two supporting members50are shown, however this is not intended to be limiting. The one or more supporting members50may be made of a rigid material, for example A36 steel, high-strength steel and aluminium. The one or more supporting members50can distribute at least a portion of a stress load that is imparted on the boom mount28to the tank30for example the rear header34. The coupling of the boom mount28to the rear header34by the one or more supporting members50distributes a portion of a stress load that is imparted upon the boom mount28by a connected boom assembly18and/or movement thereof.

An evacuation tube52is coupled to the upper surface35of the tank30. The evacuation tube52may also be referred to as an evacuation pipe, a suction tube and a suction pipe. The evacuation tube52defines an interior evacuation tube space52A. The evacuation tube52provides fluid communication between the tank space30A and the vacuum assembly38. In some embodiments of the present disclosure, the upper surface35of the tank30defines an evacuation slot56therethrough (seeFIG. 3B). The evacuation tube52also defines an evacuation tube slot55. The evacuation tube slot55is in fluid communication with the evacuation slot56. For example, the evacuation tube52may overlay a portion or all of the evacuation slot56. This arrangement defines a fluid pathway from the tank space30A, through the slots52,55into the evacuation tube space52A and onto the vacuum assembly38.

The evacuation tube52also participates in distributing at least a portion of the stress loads that can be imparted on the boom mount28and the tank30by the boom assembly18and movement thereof. One end of the evacuation tube52is coupled to the boom mount28. This coupling may distribute at least a portion of the stress loads that are imparted upon the boom mount28to the evacuation tube52. In some embodiments of the present disclosure the tank30may also include one or more further support members54that are coupled to the middle section33and the evacuation tube52, for example by welding. The one or more further supporting members54can also be referred to as struts or gussets. In the embodiment depicted in the appended figures three further supporting members54are shown, however this is not intended to be limiting. The one or more further supporting members54are made of a rigid material, for example steel. The one or more further supporting members54can distribute at least a portion of a stress load that is imparted on the evacuation tube52to the middle section33of the tank30.

As shown inFIG. 4the evacuation pipe is physically and fluidly connected to the vacuum assembly38.FIG. 5shows a vacuum-assembly flange300, which is where the evacuation tube52physically and fluidly connects to the vacuum assembly38. The components of the vacuum assembly38are known and include one or more cyclones40. The cyclones40direct a flowing evacuation stream102into a circular pattern which separates out at least a portion of any debris materials from within the evacuation stream102. The vacuum assembly38also includes a conduit42that that fluidly communicates a cyclone-output stream104to one or more filters44. The one or more filters44remove further debris materials from the cyclone-output stream104. A filter-output stream106then passes through one or more vacuum blowers44to form an exhaust stream106that exist the vacuum-excavation apparatus11by an exhaust port48. The one or more vacuum blowers44may include a silencer mechanism, or not.

In operation, the one or more vacuum blowers44generate a pressure differential that drives the flow of fluids and any debris materials entrained therein from the input end22to the exhaust port48. The pressure differential creates a suction force at the input end22of the vacuum tube20. A pressurized fluid, either a gas or liquid, is directed at the material to be excavated to generate a stream of fluidized debris-material100. The debris material becomes fluidized, even if only temporarily, in that the debris material is loosened from the surround materials and it can become airborne or otherwise drawn into the input end22by the suction force. The stream of fluidized debris-material100includes air and the fluidized debris-material, all of which are conducted through the vacuum tube20into the tank30. Within the tank30at least a portion of the debris material will settle out of the first stream100to create the evacuation stream102that has a lower debris-material content than the stream of fluidized debris-material100. Under the influence of the pressure gradient created by the one or more vacuum blowers44, the evacuation stream102passes through the slots55,56into the evacuation tube52for conduction to the vacuum assembly38. The evacuation stream102is processed in the vacuum assembly38as described above.

As the input end22is moved about the vehicle10to draw more debris material into the stream of fluidized debris-material100, the boom assembly18can pivot about the boom mount28. This pivoting imparts stress loads on the boom mount28. Due to the coupling of the evacuation tube52and the one or more support members50to the boom mount28, at least a portion of the stress load are distributed to the middle section33and the rear header34of the tank30. This stress load distribution allows a greater surface area of the tank30to bear portions of the stress loads. This may reduce or avoid focusing the stress-loads moments on smaller areas of the tank30, which smaller areas could be susceptible to stress failures. As described above, the stress load distribution allows portions of the tank30, for example the middle section33, to be made with thinner walls than a typical vacuum-truck tank, which reduces the overall weight of the vacuum-excavation apparatus11.

FIG. 5shows examples of stress-load finite element analysis data that were calculated using the ANSYS® simulation software (ANSYS is a registered trademark of SAS IP Inc.). The calculated stress-load data was superimposed over a wire diagram of the tank30. For these calculations the total vertical-load applied was about 2050 lbf and the applied moment was 2e5 inch-lbf with the boom assembly18positioned off one side of the tank30(to the left of the tank30when viewed looking straight at the rear header34) so that the direction of the moment was applied at least at the mounting flange26. Points of stress200are shown inFIG. 5where the calculated stress load values range between about 6750 pounds per square inch (psi) to about 11250 psi (one psi is equivalent to about 6.89 kilopascal). Points of higher stress202are also shown inFIG. 5where the calculated stress-load values are between about 11250 psi to about 32384 psi. The data analysis indicated that there are no points of stress200or points of further stress202occurring at the vacuum-assembly flange300.

FIG. 5also shows that there are points of stress200at least where the support members54terminate on the middle section33of the tank30(distal from the evacuation tube52). There are also points of stress200where the evacuation tube52is coupled to the boom mount28and along the longitudinal axis of the tank30where the evacuation tube52is coupled to the upper surface35. There are further points of stress200proximal to where the support members50are coupled to both of the rear header34and the boom mount28.FIG. 5Cshows that there are points of stress200at least along lateral sides of the support members50, at the point where the boom mount28is coupled to the upper surface35and between the upper surface35(in the middle section33) and an upper portion of the rear header34.FIG. 5Calso shows that there are points of higher stress202on the mounting flange26, the inner surface of the boom mount28(on the side where the boom assembly is extending from), at the points where the support members50are connected to the boom mount28and the rear header34and along an upper surface of the support members50.

Without being bound by any particular theory, the stress-load data indicates that the stress loads that are imparted upon the boom mount28by a connected boom assembly18are at least partially distributed to the rear header34, the evacuation tube52, the support members50, the further support members54and the middle section33.

In some embodiments of the present disclosure the evacuation tube52includes a pressure-relief valve53that when opened provides fluid communication between the evacuation tube space52A and the surrounding atmosphere. When closed the pressure-relief valve53provides a fluid-tight seal.

In some embodiments of the present disclosure, the vacuum-excavation assembly11may be used to move liquids from a reservoir, such as a hole or tank, into the tank30for storage and transport of the liquids.