RESONANT DEMOLITION TOOL
Reference To Pending Prior Patent Application This patent application claims benefit of (1) pending prior U.S. Provisional Patent Application
Serial No. 60/556,177, filed 03/25/2004 by Mark Nye for RESONANT DEMOLITION TOOL, and (2) pending prior U.S. Provisional Patent Application Serial No. 60/662,034, filed 03/15/2005 by Mark Nye for RESONANT DEMOLITION TOOL which patent applications are hereby incorporated herein by reference.
Field Of The Invention This invention is related to demolition apparatus and methods in general and more particularly to apparatus and methods for pulverizing a material using a resonant demolition tool.
Background Of The Invention For many demolition tasks, it is often desirable to apply a minimal amount of impact energy at a relatively high velocity. As an illustration, two examples are discussed below of an equal amount of
impact energy applied to pulverize a standard clay brick lying on a grass surface. In a first example, a 2600 lb lead weight is raised one foot above the brick and dropped. The brick is then driven down into the grass and may not even fracture. Most of the kinetic energy will be converted to heat as the sod is displaced and compressed. In a second example, a .308 rifle is positioned over the brick and the rifle is fired directly down so as to shoot the brick at point-blank range. The brick will be completely shattered such that most of the energy of the bullet fired by the rifle is converted to kinetic energy in the flying bits of brick. In both examples the impact energy is 2600 ft-lbs, but the energy transfer is quite different. High velocity impact is generally much more suited to pulverizing a material. Accordingly, it would be desirable to provide an impact tool which efficiently provides impact energy at a high velocity.
Summary Of The Invention The high velocity impact tool of the present invention provides a demolition apparatus for
pulverizing a material using resonant energy at a high velocity. An object of the invention is to provide an impact tool for pulverizing concrete. Another object of the invention is to provide an impact tool for compacting materials. Another object of the invention is to provide an impact tool for driving piles. Another object of the invention is to provide an impact tool for demolishing reinforced concrete structures . Another object of the invention is to provide an impact tool for reducing oversized quarry rocks. Another object of the invention is to provide an impact tool for freeing rock jammed in a rock crusher. Another object of the invention is to provide an impact tool for rubblizing concrete roads and runways. Another object of the invention is to provide an impact tool for curring asphalt. Another object of the invention is to provide an impact tool for driving or pulling sheet pilings. Another object of the invention is to provide an impact tool for excavating earth.
Another object of the invention is to provide an impact tool for mine sweeping. Another object of the invention is to provide an impact tool for evaluating the strength of a structure. A still further object is to provide a method for applying impact energy to a material with a tuning fork having an exciter component mounted thereto so as to pulverize material by actuating the exciter component at the first tine end of the tuning fork and applying resonant energy to the material using the second tine of the tuning fork. A still further object is to provide a method for applying impact energy to a material with a tuning fork having an exciter component mounted thereto and configured for attachment to a vehicle. A still further object is to provide a method for applying impact energy to a material with a tuning fork having an exciter component mounted thereto and configured for hand-held operation. With the above and other objects in view, as will hereinafter appear, there is provided an impact tool for applying impact energy to a material, the impact tool comprising:
a fork portion having a first tine, a second tine, and a base portion, the first tine having a first end and a second end, the second tine having a third end and a fourth end, the first end of the first tine configured adjacent the base portion, and the third end of the second tine configured adjacent the base portion; an exciter component disposed adjacent at least one of the second end of the first tine and the fourth end of the second tine, wherein the exciter component is configured to excite the first tine and the second tine to resonate sympathetically with one another at a given frequency; and a striking surface disposed adjacent at least one of the second end of the first tine and the fourth end of the second tine, wherein the striking surface is configured to contact the material with the first tine and the second tine resonating sympathetically with one another so as to apply impact energy to the material. In accordance with a further feature of the invention there is provided an impact tool for applying impact energy to a material, the impact tool comprising:
a resonating bar member having a single tine and a base portion, the single tine having a first end and a second end, the first end of the single tine configured on one side of the base portion, and the second end of the single tine configured on the other side of the base portion; an exciter component disposed at one chosen from the group consisting of the first end of the single tine, the second end of the single tine, and an anti-node disposed between the first end and the second end, wherein the exciter component is configured to excite the single tine to resonate at a given frequency; a striking surface disposed adjacent at least one of the first end of the single tine and the second end of the single tine, wherein the striking surface is configured to contact the material with the first end of the single tine and the second end of the single tine resonating sympathetically with one another so as to apply impact energy to the material; and a frame member in connection with the resonating bar member, and the frame member selectively connectable with various carrier vehicles.
In accordance with a still further feature of the invention, there is provided a method for applying impact energy to a material, the method comprising: providing an impact tool for applying impact energy to a material, the impact tool comprising: a fork portion having a first tine, a second tine, and a base portion, the first tine having a first end and a second end, the second tine having a third end and a fourth end, the first end of the first tine configured adjacent the base portion, and the third end of the second tine configured adjacent the base portion; an exciter component disposed adjacent at least one of the second end of the first tine and the fourth end of the second tine, wherein the exciter component is configured to excite the first tine and the second tine to resonate sympathetically with one another at a given frequency; and a striking surface disposed adjacent at least one of the second end of the first tine and the fourth end of the second tine, wherein the striking surface is configured to contact the material with the first tine
and the second tine resonating sympathetically with one another so as to apply impact energy to the material; raising the second tine away from the material; actuating the exciter component so as to cause the first tine and the second tine to resonate at a given frequency with increasing amplitude until a desired level of excitation is achieved and maintained; and positioning first tine and second tine to cause the second tine to strike the material while the exciter component maintains the given frequency of resonation of the second tine so as to apply impact energy to the material. The above and other features of the invention, including various novel details of construction and combinations of parts and method steps will now be more particularly described with reference to the accompanying drawings and pointed out in the claims. It will be understood that the particular devices and method steps embodying the invention are shown by way of illustration only and not as limitations of the invention. The principles and features of this invention may be employed in various and numerous
embodiments without departing from the scope of the invention .
Brief Description Of The Drawings These and other objects and features of the present invention will be more fully disclosed or rendered obvious by the following detailed description of the preferred embodiments of the invention, which are to be considered together with the accompanying drawings wherein like numbers refer to like parts, and further wherein: Fig. 1 is a schematic view of one form of a resonant demolition tool having a tuning fork configured for attachment to a thirty ton excavator, illustrative of a preferred embodiment of the present invention; Fig. 2 is another schematic view of the tuning fork and rotatble connector component of the resonant demolition tool as shown in Fig. 1; Fig. 3 is a schematic view of another preferred embodiment of the present invention with a resonant demolition tool having a resonating bar member with a frame selectively attachable to a carrier vehicle;
Figs. 4A-4G are schematic views of various components disposed at the striking surface of a working tine or an impact tool; Fig. 5 is a schematic view of another preferred embodiment of the present invention with a resonant demolition tool having a tuning fork with a pair of radically curved tines; Figs. 6-8 are diagrammatic illustrations of a model of an impact tool with a pneumatically driven exciter component mounted on an exciter tine; Figs. 9-11 are diagrammatic illustrations of an impact tool of the present invention having a handle mounted at the base of the tuning fork for hand-held operation by a single operator; and Figs. 12-18 are diagrammatic illustrations of an impact tool of a preferred embodiment of the present invention having a tuning fork as shown in Figs. 1 and 2.
Detailed Description Of The Preferred Embodiments Referring to Fig. 1, and in a preferred embodiment of the present invention, there is shown a resonant impact tool 5 for pulverizing concrete and performing
other various tasks. Resonant impact tool 5 is referred to herein below as impact tool 5. Referring to Figs. 1 and 2, and in a preferred embodiment of the present invention, impact tool 5 comprises a steel profile forming a very large tuning fork 10. For a typical carrier 15, such as a thirty ton excavator 15, the overall length is preferably about 2000 mm to about 3500 mm and the thickness is preferably about 100 mm to about 250 mm. A base portion 12 of fork 10 is preferably pivotally mounted to an arm 20 of carrier apparatus 15 with a rotatable connector component 17. Two existing bucket pins 25 are attached to rotatable connector component 17 such that tuning fork 10 can be angled up and down by the machine's bucket cylinder 30. A turn-table 35 attached by pins 35A to base 12 of fork 10 between fork 10 and carrier machine 15 allows the entire assembly to be rotated so a working tine 40, having a striking surface 45, can be used at any angle. In one preferred embodiment of the present invention, a striking surface is located on each of tine 40 and 50. In another preferred embodiment of the
present invention, a striking surface is located on tine 50 instead of tine 40. A resonant tine 50 of fork 10 is excited by an exciter 55, which is preferably a motor driven rotating eccentric weight 55A mounted at an end 60 of tine 50.
Working tine 40 resonates sympathetically with resonant tine 50 as it is excited by exciter 55. An enlarged striking surface 45 at an end 65 of working tine 40 is used to deliver blows to the material to be demolished. As discussed herein below, and in other preferred embodiments of the present invention, working tine 40 may include other tools disposed thereon. Preferably, the tine displacement or amplitude of working tine 40 is about 15 mm to about 30 mm. This amplitude is proportional to excitation strength provided by the motor driven weight 55A, and can be varied by changing the mass and radius of rotating eccentric weight 55A. Preferably, the impact frequency is about 10 Hz to about 500 Hz, and, more preferably, the impact frequency is about 30 Hz to about 60 Hz, which is set by the length of tine 45. Impact energy provided at
enlarged striking surface 45 is a function of the amplitude, frequency and mass of tine 45. In a preferred embodiment of the present invention, fork 10 comprises one or more selected materials. For example, these materials may include, but are not limited to, at least one of steel, carbon fiber, aluminum, and monel, for non sparking applications . In an alternative embodiment of the present invention, a fork portion is laminated vertically with multiple portions joined together at the locations of the nodes such that the fork portion has a construction similar to a transformer (not shown) . In an alternative embodiment of the present invention, a fork portion is laminated horizontally with multiple portions joined together at the locations of the nodes such that the fork portion has a construction similar to a leaf spring (not shown) . Referring now to Fig. 3, and in a preferred embodiment of the present invention, there is shown a resonating bar member 10A. A frame 67 preferably connects resonating bar member 10A to rotatable
connector component 17 with a fixed node pin 69 and a suspension link 70 to a floating node pin 75. In an alternative embodiment of the present invention, a resonating bar member is laminated vertically with multiple portions joined together at the locations of the nodes such that the bar member has a construction similar to a transformer (not shown) . In an alternative embodiment of the present invention, a resonating bar member is laminated horizontally with multiple portions joined together at the locations of the nodes such that the bar member has a construction similar to a leaf spring (not shown) . Impact tool 5 may be used to drive a pick, chisel, plate packer, rotating drill, sheet pile driving clamp, replaceable impact hammer, blender, mixer or one or more other tools. Referring now to Figs. 4A-4F, and in a preferred embodiment of the present invention, working tine 40 of impact tool 5 preferably includes, but is not limited to, one or more various components 45A, 45B, 45C, 45D, 45E, 45F, and 45G disposed at striking surface 45 of working tine 40.
Looking at Fig. 4A, there is shown impact tool 5 with component 45A configured for rapid demolition of steel reinforced concrete structures. For example, component 45A preferably comprises a round or flat chisel point. Looking at Fig. 4B, there is shown impact tool 5 with component 45B configured for compacting materials. For example, component 45B preferably comprises a compactor foot. Looking at Fig. 4C, there is shown impact tool 5 with component 45C configured for driving piles, demolishing reinforced or non-reinforced concrete structures, reducing oversized quarry rocks, freeing material jammed in rock crushers, or rubblizing concrete road beds or runways. For example, component 45C preferably comprises an elephant foot. Looking at Fig. 4D, there is shown impact tool 5 with component 45D configured for cutting asphalt. For example, component 45D preferably comprises a cutter wheel. Looking at Fig. 4E, there is shown impact tool 5 with component 45E configured for driving or pulling
sheet pilings. For example, component 45E preferably comprises a clamp. Looking at Fig. 4F, there is shown impact tool 5 with component 45F configured for excavating earth. For example, component 45F preferably comprises a spoon blade 45F. Looking at Fig. 4G, there is shown impact tool 5 with component 45G configured for mine sweeping. For example, component 45G preferably comprises a multi-tined rake 45G. Preferably, the multiple tines of multi-tine rake 45G are configured to sift and travel through the dirt, raking, without plowing. In a preferred embodiment of the present invention (not shown) , impact tool 5 is configured for evaluating the strength of structures. For example, the impact frequency of working tine 40 of impact tool 5 is selectively adjusted to test concrete columns for seismic stability. Referring to Fig. 5, and in a preferred embodiment of the present invention, there is shown an impact tool 5B comprising an alternatively shaped tuning fork 10B having a pair of radically curved tines 40A and 50A.
In another preferred embodiment of the present invention (not shown) , variable length tines are preferably provided to allow resonant frequency adjustment so as to provide a matching frequency for optimized performance relative to various materials. In a preferred embodiment of the present invention, impact tool 5 is configured to be mounted on various types of stationary or mobile equipment. Looking at Figs. 6-8, and in a preferred embodiment of the present invention, there is shown a table mounted impact tool 80 having a support portion 85 for holding base 12 of tine 40 and tine 50. A pneumatic system 90 is provided to drive a pneumatic motor, which in turn drives weight 55A (Fig. 1). Referring now to Figs. 9 and 10, and in a preferred embodiment of the present invention, there is shown a resonant impact tool 105 having a handle 135 configured for hand-held operation by a single operator. Preferably, handle 135 includes a pair of hand grips 135A and 135B in attachment to base portion 115. Looking at Figs. 9-11, and in a preferred embodiment of the present invention, there is shown
exciter 55 with an electric motor 55D to drive weight 55A (Fig. 1) . In another preferred embodiment of the present invention, the motor of exciter 55 preferably comprises a rotary hydraulic motor, a pneumatic motor, or an electric motor. In another preferred embodiment of the present invention, exciter 55 preferably comprises a linear actuator, a magnetic coil, a piezoelectric motor or an internal combustion engine. Referring now to Figs. 12-15, and in a preferred embodiment of the present invention, there is shown a resonant impact tool 5 with a hydraulic exciter component 200 and a machine mount 205 (Figs. 14-18) configured for attachment to a vehicle 210 (Figs. 14 and 17) .
DESCRIPTION OF A PREFERRED METHOD OF OPERATION In a preferred embodiment of the present invention, a method for operating impact tool 5 preferably comprises the following steps. First, tine 40 and tine 50 are raised away from the material. Second, exciter motor 55 is started. Third, tine 40 and tine 50 each begin to resonate with increasing
amplitude until fully excited. Fourth, tine assembly 10 is rotated and positioned to cause one or both of excited tine 40 and excited tine 50 to strike the material to be pulverized.
Advantages Of The Present Invention The impact tool of the present invention is scalable within a wide range of sizes and uses. The impact tool of the present invention is configured for quiet operation due to a low amount of energy needed per impact. The impact tool of the present invention has a relatively simple construction, with no precision parts . The impact tool of the present invention does not require any special alloys or heat treated parts. The impact tool of the present invention is able to produce smaller rubble due to high energy rate. The impact tool of the present invention is able to process unsupported material as it does not require anything to hit against. The impact tool of the present invention does not drive material down or away from striking surface.
The impact tool of the present invention is able to use the material's own inertia to shatter it at high velocity. The impact tool of the present invention is able to demolish items of relatively low mass. The impact tool of the present invention produces very little or no seismic disturbance. The impact tool of the present invention does not shake the surrounding ground or foundations. The impact tool of the present invention is configured for applications in connection with urban search and rescue inasmuch as it does not cause movement of structures and is distinct from a hydraulic hammer or breaker. Some potential disadvantages of the impact tool of the present invention may include fatigue cracking of the tines and that careful control of application pressure may be required to avoid instances of stalling and loss of excitation when too much application pressure is applied to the working tine. Having described preferred embodiments of the invention with reference to the accompanying drawings, it is to be understood that the embodiments shown herein are by way of example, and that various changes
and modifications may be effected by one skilled in the art without departing from the scope or spirit of the invention as defined in the following claims.