I. BACKGROUND A. Field of the Invention This invention generally relates to methods and apparatuses related to displacing a material and creating a void, and more specifically to methods and apparatuses related to excavating or digging holes in the ground, such as might be used to create cylindrically-shaped voids in the ground suitable to receive utility poles and the like, and even more specifically to a method and apparatus to use suction and vibration to excavate and thereby to eliminate the need for fluid to be used with suction systems.
B. Description of Related Art It is known in the art to use various methods and apparatuses to excavate. It is also known to use vibration energy vibration to create the excavation. What is needed is a new method of removing the loose soil when a hole or trench etc. in the ground is desired. This invention will provide numerous other advantages as will be readily understood by a person of skill in the art.
II. SUMMARY According to some embodiments of this invention, the apparatus includes a vacuum generator, a tank, a boom, a vacuum tube, attached to the vacuum tube is a vibration energy vibration generator. The frequency is adjustable from 20 Hz to 20,000 Hz making it possible to run at the resonant frequency of the vacuum tube. Often, these vibrations are in the sonic range. These vibrations are transferred from the vacuum tube to the adjacent soil which loosens and fluidizes the soil. “Fluidization” is commonly known as a process like liquefaction whereby a granular material is converted from a static solid-like state to a dynamic fluid-like state. This process occurs when a fluid is passed up through the granular material. In this application, the fluid is air. Fluidizing the soil reduces its friction and lowers the force necessary to push the vacuum tube into the ground. The vibrations also break the soil into small sized chunks without the need of pressurized fluid systems. This allows the soil to be conveyed by the vacuum tube to the storage tanks. The vibration frequency can be optimized for the qualities of the soil at each excavation site. The operator can adjust or optimize the frequency until, once optimized, the vacuum tube is easily pushed straight down into the earth forming a straight hole the approximate size of the vacuum tube. Forming trenches, pits or troughs is easily accomplished by forming a series of holes in the proper configuration. By minimizing the required boom travel for a particular excavation, the time required is significantly reduced.
III. BRIEF DESCRIPTION OF THE DRAWINGS The invention may take physical form in certain parts and arrangement of parts, embodiments of which will be described in detail in this specification and illustrated in the accompanying drawings which form a part hereof and wherein:
FIG. 1 is a schematic, side view of the inventive apparatus mounted to an associated vehicle, according one embodiment of the invention.
FIG. 2 is a schematic, front view of a vibration energy generator mounted to a vacuum tube.
FIG. 3 is a schematic, side view of the vibration energy generator mounted to the vacuum tube.
FIG. 4 is a schematic, side view of a vacuum generator according to one embodiment of the invention.
FIG. 5 is a side elevation showing a prior art vacuum excavation with pressurized fluid jets producing tapered holes.
FIG. 6 is a side elevation showing the inventive method and apparatus producing straight, cylindrical holes.
FIG. 7 is a front view of the inventive apparatus and method shown suspended between two A-frames according to an embodiment of the invention.
FIG. 8 is a top view of a hole drilled in the earth by the inventive method and apparatus, and to provide a sense of size one can see the left and right foot of the operator as well as a work glove lying on the ground to provide perspective.
FIG. 9 is a side view of the inventive apparatus, showing the vibration generator clamped to the vacuum tube.
FIG. 10 is the same view as FIG. 9 but rotated 90 degrees.
FIG. 11 is a perspective view of a shaft, eccentric weight, and bearing from a vibration generator.
FIG. 12 is a perspective view of a shaft, eccentric weight, and bearing from a vibration generator.
IV. DETAILED DESCRIPTION Referring now to the drawings wherein the showings are for purposes of illustrating embodiments of the invention only and not for purposes of limiting the same, and wherein like reference numerals are understood to refer to like components, the inventive apparatus 10 is shown in FIGS. 1-12. More specifically, the inventive method and apparatus 10 primarily comprises three operative elements: a vacuum generator 18, vacuum tube 22 and a vibration generator 14. Throughout this disclosure the material to be excavated is represented to be ground or soil, but it is within the scope of the invention that other materials can be moved thereby. Similarly, the invention is disclosed with respect to a vacuum tube and is illustrated as cylindrical. However, the operation of the vacuum tube does not require cylindrical shape and “vacuum tubes” of other cross-sections are within the scope of the invention.
With reference to FIG. 5, prior art vacuum excavation 32 employs pressurized jets of fluid, commonly water or air, to loosen the associated soil 42 or other debris materials. The pressurized fluid is commonly created by a pressure-generating system 34, such as a pump, mounted on the associated vacuum system 30. The pressurized fluid is conducted via conduit 40 to the excavating site 46 through hand-held lances or wands 26. A vacuum system 30 then conveys these debris materials through a vacuum tube 38 to a storage tank 48, thus creating a hole, a pit, a trench, or other excavation 46. Vacuum excavation can be used to expose underground utilities in a manner which is safer than using shovels or traditional digging equipment. This is a typical prior art system. With reference to FIG. 5, note that excavation site 46 is not cylindrical, but rather funnel shaped.
Typically, vacuum excavation apparatuses are transported upon large vehicles or trailers. The vehicles can carry liquid pressurization or pneumatic equipment, containers for storing the liquid or pressurized air, vacuum equipment, and large tanks for storing the excavated soil, rocks, and other material. A boom 50 is typically mounted to the storage tank to connect the vacuum tube to the tank. The boom 50 allows the operator to move the inlet end of the vacuum tube during excavation operations.
The fluid pressurizing systems require the vehicle to carry pumps, compressors, tanks and usually water. The pumps, compressors, tanks, and water add weight to the vehicle and take up space, thereby reducing the amount of excavated material the vehicle can carry. The pumps, compressors, tanks and in some cases the water, all need to be purchased and thereby add cost to the prior art method and apparatus. The pressures involved, approximately 2,000 psi for water systems and 200 psi for air systems, can pose safety concerns and can require specialized training or certification. Fluid pressurizing systems can be regulated or restricted at some sites or locations. While the prior art high pressure, high velocity jets can adequately loosen the soil for the vacuum system, they can also cause flying debris, dust for the air systems and mud for the liquids systems.
When vacuum excavating utilizing pressurized fluid, the soil is first loosened with the fluid. The vacuum tube is then positioned over the loosened soil using the boom. The loosened material is conducted pneumatically to the storage tank using the vacuum system. The vacuum tube is then positioned out of the way using the boom to allow more soil to be loosened before returning the vacuum tube to remove the newly loosened soil. This method requires considerable movement of the boom 50 and vacuum tube 38, neither of which is precisely nor easily controlled. Vacuum excavation with pressurized fluid does not produce straight holes. The holes are tapered and larger at the top to gain access for the wand or lance to loosen soil at the bottom of the hole. This requires removing more material than would be required to produce a straight hole. As the excavating depth increases the difficulty dramatically increases. For example, excavating at depths of 10 feet typically require lances 16 feet long. Handling lances of this size is very difficult, and the visibility needed to effectively operate them at this depth is seldom available. The flying debris caused by jetting the soil also creates a mess requiring more time to clean up when the excavation is complete. A final consideration is the excavated soil and water mixture can result is special handling or dumping considerations.
FIG. 1 shows one embodiment of the inventive vibration-vacuum apparatus 10. The vibration-vacuum apparatus comprises of a vacuum tube 22, vibration generator 14, boom 50, storage tank 48, and a vacuum generator 18, which can all be advantageously mounted on an associated vehicle 54. The associated vehicle 54 can be driven to a desired location and the vacuum tube 38 can be deployed wherever vacuum is desired.
With continuing reference to FIG. 1, the vacuum tube 22 has a first end 56 and a second end 58. The vacuum tube 22 is operatively associated with the vibration generator 14. Using the boom 50, a second end 58 of the vacuum tube 22 is positioned over a portion of the associated soil or ground 42 where a hole is to be created. The vacuum generator 18 can be engaged to create a suction or vacuum and to provide it to the vacuum tube 22. Then, the vibration generator 14 can be operatively engaged to cause the vacuum tube 22 to oscillate and vibrate. The vibration generator 14 can be adjusted to vibrate at a frequency effective to fluidize the associated soil 42 effectively. When the apparatus 10 operates thusly, the second end 58 of the vacuum tube 22 vibrates against the associated soil 42, thereby loosening the associated soil 42 and causing it to fluidize in an area adjacent to the second end 58 of the vacuum tube 22. The loosened or fluidized soil 42 capable of being lifted and removed by the suction, and travels upwardly through the vacuum tube 22, from the second end 58 toward the first end 56, and eventually into the tank 48.
With continuing reference to FIG. 1, due to the foregoing, the second end 58 of the vacuum tube 22 essentially becomes the point of attack, or the surface that marks the progress of the creation of the associated hole, as the second end 58 moves downwardly into the associated ground 42. Should a deeper hole be desired, multiple lengths of tube 22 can be operatively connected, with such connection being made to eliminate or minimize any loss of vacuum, as is within the ordinary skill of the art. Overall, the vibration energy created by the vibration generator 14 drives the leading, second end 58 of the vacuum tube 22 downwardly into the associated ground 42 while the vacuum generator 18 pneumatically conveys the fluidized ground 42 upwardly through the interior of the vacuum tube 22 to the storage tank 48.
As can be seen in various figures, and with special reference to FIGS. 2 and 3, the vibration generator 14 is securely but selectively affixed to the vacuum tube 22 in some sort of a method chosen with sound engineering judgement. In one example, the vibration generator 14 is attached to the vacuum tube 22 using first and second split type clamps 66, 68, respectively, welded to the vacuum tube 22 and secured with two fasteners 70. FIG. 3 shows a side elevation of the vibration generator 14 affixed to the vacuum tube 22 with split type clamps 66, 68 welded to the vacuum tube 22.
With reference to FIGS. 11 and 12, the vibration generator 14 will be described. Any vibration generator 14 chosen with sound engineering judgment can work with the invention. Essentially, the vibration generator 14 is capable of selectively oscillating the vacuum tube 22 within a preferred frequency range. One vibration generator 14 operates to create vibrations by rotating a shaft 96 with an eccentric weight. The shaft is mounted between two bearings 98 and enclosed in a casing 100 that contains the necessary lubricant. The shaft 96 can be rotated by various methods including a hydraulic motor. The rotational speed of the shaft is adjusted to produce vibrations ranging from 20 Hz to 20,000 Hz. An example of vibration generator 14 that works well with the invention is sold by the WINK Vibracore Drill Company of 4400 Smith Crescent, Richmond, BC V6V 1S7, Canada.
FIG. 4 shows a schematic side elevation of the vibration-vacuum apparatus 10. A vibration generator 14 is affixed to the vacuum tube 22. Vibrating the vacuum tube 22 cause the soil 42 near the second end 58 of the vacuum tube 22 to loosen and to fluidize. The fluidized soil enters the second 58 end of the vacuum tube 22 and is conveyed past the first end 56 of the vacuum tube 22 and into the storage tank 48 passing through the boom 50. In the storage tanks 48 most of the associated heavier debris drops out of the excavation stream which continues through one or more cyclones and connective duct work. The circular path in the cyclone cause most of the debris material to fall out of the stream. One or more blowers or fans are used to generate the system vacuum. An inlet filter to the blowers or fans removes any remaining particles large enough to damage the blowers or fans. The stream then passes through an optional exhaust silencer and to the atmosphere.
FIG. 5 depicts a prior art vacuum excavation operation utilizing pressurized fluid jets. The associated operator 74 loosens the soil 42 by directing a pressurized fluid stream at the ground 42. The vacuum generator 18 conveys the loosened material fluid mixture 42 through the inlet or second end 58 of the vacuum tube 22, through the boom 50 and to the storage tank 48. Most of the heavier debris 42 falls out of the stream in the storage tank 48. The excavation stream continues through the duct work to one or more cyclones where more debris particles are separated from the stream. After the cyclone(s) the stream continues to a blower or fan inlet filter, through an optional exhaust silencer and to the atmosphere. As the depth of the associated hole 46 increases the top of the hole 46 must be enlarged to provide the operator 74 access to direct the pressurized fluid stream to the bottom of the hole 46 and to give the operator 74 space to locate the boom 50 temporarily out of the way. Enlarging the hole 46 in this manner requires removing more material, ground, or soil 42 than necessary to form the hole 46. This excess material removal takes additional time reducing the productivity of the operation. This extra material is also part of the payload of the vehicle requiring more trips to unload for a given excavation. In systems utilizing water or some other liquid as the pressurized fluid this liquid is mixed with the excavating material increasing its weight, requiring stronger or larger vehicles or vehicles with additional axles. The vacuum tube does not collect all the loosened soil & fluid mixture, the portion of the mixture not collected is scattered into the surrounding area. This generates large dust clouds in air excavating systems or scatters mud everywhere for liquid excavating systems.
In contrast to the prior art excavation method and apparatus depicted in FIG. 5, FIG. 6 depicts the inventive vibration-vacuum excavation method and apparatus. The vibration-frequency vibration generator 14 is attached to the vacuum tube 22 in a manner like FIG. 2. The vibration frequency is adjustable from 20 Hz to 20,000 Hz making it possible to run at the resonant frequency of the vacuum tube 22, which is one preferred operating mode. These vibrations are transferred from the vacuum tube 22 to the adjacent soil which loosens and fluidizes. Fluidizing the soil 42 reduces its friction and lowers the force necessary to push the vacuum tube 22 into the ground. In some applications, at certain frequencies, the vacuum tube 22 will penetrate the soil 42 under the weight of the vacuum tube 22. In other applications, and at other frequencies, the boom 50 can be used to push the vacuum tube 22 into the soil 42. The vibrations cause the vacuum tube 22 to break the soil 42 into small chunks without the need of pressurized fluid systems. Thereby, soil 42 may be removed by the vacuum tube 22 forming a straight, cylindrical hole 46 which has a hole diameter approximately the diameter of the vacuum tube 22. The vacuum generator 14 conveys the loosened soil 42 through the second end 58 of the vacuum tube 22, through the boom 50 and to the storage tank 48. Most of the heavier debris or soil falls out of the soil stream in the storage tank. The excavation soil stream continues through the duct work to one or more cyclones where more debris particles are separated from the soil stream. After the cyclone(s) the soil stream continues to a blower or fan inlet filter, through an optional exhaust silencer and to the atmosphere.
With reference to FIG. 7, the apparatus 10 is shown, with the vibration generator 14 shown clamped to the vacuum tube 22 via clamps 66, 68. The apparatus 10 is shown supported by an associated sawhorse 92.
With reference to FIG. 8, an associated hole 80 made in the associated ground 42 is illustrated, such as may be produced by the disclosed method and apparatus is shown. The associated operator's shoes 84, 86 and work glove 88 are shown to provide perspective.
With reference to FIGS. 9 and 10, the apparatus 10 is shown with the vibration generator 14 shown clamped to the vacuum tube 22 via clamps 66, 68.
The inventive method and apparatus can produce straight holes via suction and vibration without the use of fluids, such as water or air.
Numerous embodiments have been described herein. It will be apparent to those skilled in the art that the above methods and apparatuses may incorporate changes and modifications without departing from the general scope of this invention. It is intended to include all such modifications and alterations in so far as they come within the scope of the appended claims or the equivalents thereof. Further, the “invention” as that term is used in this document is what is claimed in the claims of this document. The right to claim elements and/or sub-combinations that are disclosed herein as other inventions in other patent documents is hereby unconditionally reserved.
