Abstract:
The present invention is directed to a tire comminution apparatus that is of simple construction and that can be operated without excessive maintenance. According to the present invention, a vehicle tire of any size or composition can be comminuted with essentially the same comminution apparatus. The comminution apparatus includes a freely moving lance with a nozzle for transforming a liquid into a high velocity liquid jet. The lance is positioned and controlled such that the liquid jet impacts the tire thereby separating it into its component parts. The comminution apparatus may be computer controlled.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates generally to the comminution of solid materials. More particularly, this invention relates to an apparatus used to reduce the size of solid materials into smaller components by means of a processor-controlled liquid jet. More particularly, the present invention relates to an apparatus for separating a vehicle tire into its components using a processor-controlled high velocity liquid jet. 
     2. Related Art 
     The disposal of used vehicle tires presents an ever increasing environmental concern. In California alone, over 28 million tires require disposal each year. A tire disposal apparatus and process that balances an environmentally friendly and cost effective approach is crucial to the resolution of this problem. 
     Traditional methods of tire disposal include burying tires in landfills, either whole or shredded. The disadvantage to burying whole tires is the tremendous volume of space they occupy in already scarce landfills. In addition, whole tires have a tendency to resurface over time when the dirt with which they are covered settles. Shredded tires take up less space in landfills, however, the cost of shredding tires is quite high due to the high capital expense of current tire shredding machinery and the high maintenance costs associated therewith. Burying tires, whole or shredded, also results in the waste of useful material that may be reclaimed from the tires, such as rubber and steel. 
     As mentioned above, new tire disposal methods are needed that do not tax scarce landfill space and that efficiently reclaim the material of used tires. There are various uses for the reclaimed materials of tires. For instance, crumb rubber may be used in asphalt to make roads smoother and quieter, in new tires and retreads, in composite materials such as thermoplastics and in various industrial applications including the production of roofing materials, siding, automotive parts, flooring and electrical insulation. To this end, an alternative to burying tires has been to use spent tires as a fuel source as Tire Derived Fuel (TDF) in power and cement plants. If tire rubber is burned in furnaces at high temperatures, it will produce energy without noxious fumes. However, in order to achieve an efficient burn with less noxious by-products, the tire rubber must be separated from the other materials of which it is comprised, i.e., the fabric and steel used to reinforce the tread and sidewalls of the tire. Once again, apparatus and methods are currently available to perform such functions, but the machinery is expensive and requires constant maintenance due to the inherent toughness of tires, the variation in materials of which tires are comprised and the various sizes of vehicle tires. 
     Therefore, what is needed is an economical apparatus for comminuting a tire into the materials of which it is constructed. Further, what is needed is an apparatus that is affordable and easily maintained as well as usable by a variety of users in a variety of locations, i.e., within automobile and truck tire manufacturing facilities, in tire reclamation facilities, etc. 
     SUMMARY OF THE INVENTION 
     The present invention is directed to a comminution apparatus that is of a simple construction and that can be operated without excessive maintenance. According to the present invention, a vehicle tire of any size or composition can be comminuted with essentially the same comminution apparatus. The comminution apparatus includes a freely moving lance with a nozzle for transforming a liquid into a high velocity liquid jet. The lance is positioned and controlled such that its liquid jet impacts the tire thereby separating it into its component parts. 
     The comminution apparatus is comprised of two concentric cylindrical tubes that each rotatably support a bearing plate in an interior area thereof. The bearing plates are a distance L apart and rotate at variable speeds n 1  and n 2  respectively. Each bearing plate includes a bearing in a bearing passage that is located a distance r 1  and r 2  respectively from a longitudinal center axis X—X of the concentric cylindrical tubes. The bearings support a lance that is comprised of a flexible hose at an upper end thereof and a nozzle at a lower end thereof. 
     As the bearing plates rotate, clockwise or counterclockwise the lance orbits about center axis X—X. A flexible hose which is attached to an upper portion of the lance accommodates the orbital movement of the lance which translates into the movement of the liquid jet emanating from the lance nozzle. By varying bearing plate speeds n 1  and n 2 , distance L and a third variable S (the stand-off distance between the nozzle exit and the article to be comminuted), the liquid jet distribution patterns can be adjusted as necessary to achieve effective tire comminution. 
     The comminution of the tire may be computer controlled through the use of an imaging device that constantly monitors the comminution process and redirects the liquid distribution of the lance as necessary to efficiently reclaim the material of the tire. Upon completion of the initial comminution process, the tire materials are separated and possibly further processed by additional high velocity liquid jets in a process such as the one described in co-pending application Ser. No. 09/413,489 filed Oct. 6, 1999, incorporated herein in its entirety by reference. 
     The comminution apparatus of the present invention is of a relatively simple construction and is not subject to the excessive mechanical wear associated with current tire shredding machinery. Further, the tire comminution apparatus of the present invention readily accommodates whole tires of varying sizes without the additional cost or time associated with cutting up a tire into strips or debeading a tire, as required by many of the current tire comminution apparatus. 
     Further features and advantages of the present invention, as well as the structure and operation of various embodiments of the present invention, are described in detail below with reference to the accompanying drawings. 
    
    
     BRIEF DESCRIPTION OF THE FIGURES 
     The accompanying drawings, which are incorporated herein and form part of the specification, illustrate the present invention and together with the description further serve to explain the principles of the invention and to enable a person skilled in the pertinent art to make and use the invention. 
     FIG. 1 is schematic diagram of an apparatus for comminution of solid materials of the present invention. 
     FIG. 2 is a schematic diagram of an alternate embodiment of the apparatus of FIG. 1 wherein distance L is adjustable. 
     FIG. 2A is a schematic diagram of the bearings of FIG.  2 . 
     FIG. 3A illustrates a random distribution pattern of the processor-controlled liquid jet of FIG.  2 . 
     FIG. 3B illustrates a ring distribution pattern of the processor-controlled liquid jet of FIG.  2 . 
     FIG. 3C illustrates a sectional distribution pattern of the processor-controlled liquid jet of FIG.  2 . 
     FIG. 3D illustrates a circular distribution pattern of the processor-controlled liquid jet of FIG.  2 . 
     FIG. 3E illustrates a point distribution pattern of the processor-controlled liquid jet of FIG.  2 . 
     FIGS. 3F and 3G illustrate various linear distribution patterns of the processor-controlled liquid jet of FIG.  2 . 
     FIG. 4 is an example of a computer system that could be used for computer controlled monitoring of comminution of solid materials in accordance with the present invention. 
     FIG. 5 is a schematic diagram of an alternate embodiment of the apparatus of FIG. 1 wherein stand-off distance S is adjustable. 
     FIG. 6 is a schematic diagram of a revolving nozzle head. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     A preferred embodiment of the present invention is now described with reference to the figures where like reference numbers indicate identical or functionally similar elements. Also in the figures, the left most digit of each reference number corresponds to the figure in which the reference number is first used. While specific configurations and arrangements are discussed, it should be understood that this is done for illustrative purposes only. A person skilled in the relevant art will recognize that other configurations and arrangements can be used without departing from the spirit and scope of the invention. It will be apparent to a person skilled in the relevant art that this invention can also be employed in a variety of other applications. 
     FIG. 1 is schematic diagram of an apparatus for comminution of solid materials of the present invention. Comminution apparatus  100  is particularly useful in the comminution of used vehicle tires into their component parts. In another embodiment, the comminution apparatus may be used to comminute anthracite, silicon rods used in the production of semi-conductor chips, organic material such as wood or a variety of other materials as would be apparent to one skilled in the relevant art. 
     Comminution apparatus  100  is comprised of an inner cylindrical tube  101  and an outer cylindrical tube  102  that are concentric about longitudinal axis X—X, as shown in FIG.  1 . Outer cylindrical tube  102  has an internal diameter of between 2 inches and 2 feet depending on the material to be comminuted and the application in which comminution apparatus  100  is to be used. The internal diameter of inner cylindrical tube  101  will be less than that of outer cylindrical tube  102  to accommodate its being positioned within outer cylindrical tube  102 . 
     An upper bearing plate  104  is rotatably supported within the interior area of inner cylindrical tube  101  and a lower bearing plate  106  is rotatably supported within the interior area of outer cylindrical tube  102 . Upper and lower bearing plates  104  and  106  are spaced distance L apart. 
     As shown in FIG. 1, a lance  110  has an internal portion  112  that is supported by upper and lower bearing plates  104  and  106  and an external portion  114  that extends beyond a lowermost portion  115  of cylindrical tube  102 . Lance internal portion  112  is supported by an upper bearing  116  of upper bearing plate  104  and a lower bearing  118  of lower bearing plate  106 . Upper bearing  116  is distance r 1  from the longitudinal center axis X—X of inner and outer cylindrical tubes  101  and  102 . Lower bearing  118  is distance r 2  from the longitudinal center axis X—X. In an alternate embodiment of the present invention, distances r 1  and r 2  may be radially adjustable so as to allow lance  110  to be repositioned, thereby providing a greater radial range of liquid jet trajectories for the effective comminution of solid materials. 
     Lance internal portion  112  is attached to a flexible hose  120  on an upper portion thereof. Lance external portion  114  includes a nozzle  122  which transforms a liquid supplied through flexible hose  120  into a high velocity liquid jet. Nozzle  122  may be comprised of a nozzle block with multiple stable nozzles attached thereto. In a further embodiment, nozzle  622  may be either a self-revolving nozzle head or a driven nozzle head with an independent motor that revolves around axis Y—Y, as shown in FIG.  6 . Further, it will become apparent to one skilled in the relevant art to utilize a combination of rotating nozzle heads and stable nozzle heads in accordance with the present invention to accommodate various comminution applications. 
     As mentioned above, upper and lower bearing plates  104  and  106  are rotatably supported by inner and outer cylindrical tubes  101  and  102  respectively. Upper and lower bearing plates  104  and  106  include means by which each is rotated by step motors  124  and  126  respectively. For instance, each bearing plate may include gears  140  and  142  which mesh with respective gears  144  and  146  of step motors  124  and  126 , as schematically represented in FIG.  1 . Step motors  124  and  126  can be any commercially available stepper motor system, such as the PE Series stepper motors manufactured by Nippon Pulse Motor Co., Ltd. of Radford, Va., that can be adapted for use in the present invention. Step motor  124  rotates upper bearing plate  104  at speed n 1  and step motor  126  rotates lower bearing plate  106  at speed n 2 , wherein speeds n 1  and n 2  may be independently varied. 
     FIG. 2 is an alternate embodiment of the present invention wherein distance L is adjustable by step motor  228 . Step motor  228  raises and lowers inner cylindrical tube  101  within outer cylindrical tube  102  to vary distance L. Inner cylindrical tube  101  may “slide” along outer cylindrical tube  102 , or be supported by outer cylindrical tube  102  by means known to one of ordinary skill in the art, such as by rollers interposed between the two tubes. In this embodiment, step motor  124  rotates upper bearing plate  104  at speed n 1  and step motor  126  rotates lower bearing plate  106  at speed n 2 . As shown in FIG. 2A, an upper bearing  116  prohibits lance  110  from sliding axially. However, a lower bearing  118  allows axial movement between upper and lower bearing plates  104  and  106  as distance L is adjusted. 
     Flexible hose  120  flexes to allow lance internal portion  112  to orbit about longitudinal center axis X—X while supported by bearings  116  and  118  that move within rotating upper and lower bearing plates  104  and  106  respectively. The movement of lance internal portion  112  about the longitudinal center axis X—X of inner and outer cylindrical tubes  101  and  102  translates into the movement of lance external portion  114 . By adjusting bearing plate speeds n 1  and n 2  and/or distance L, the trajectory of nozzle  122  of lance external portion  114  may be controlled so that the distribution of the liquid jet on the surface of the material to be comminuted may be varied as shown in FIGS. 3A-3G. 
     FIGS. 3A-3G represent various liquid jet trajectory distributions that can be achieved by varying upper bearing plate speed n 1 , lower bearing plate speed n 2  and/or distance L. The liquid jet distribution can be set a priori or determined automatically by computer controlled monitoring of the material to be comminuted during the comminution process. Such computer controlled monitoring can be performed by the computer system described below. 
     In an alternate embodiment of the present invention as shown in FIG. 5, the stand-off distance S between the nozzle exit and the material to be comminuted may be adjusted by moving either lance  110  or the material to be comminuted. In this way, another parameter may be controlled to provide further adjustment and refinement of the liquid jet trajectory distribution during the comminution process. 
     Referring to FIG.  4  and as discussed above, an example of a computer system  400  that can be used to control the comminution process is shown. Computer system  400  includes one or more processors, such as processor  404 . Processor  404  is connected to a communications infrastructure  402 . After reading this description, it will become apparent to a person skilled in the relevant art how to implement the invention using other computer systems and/or computer architectures. 
     Computer system  400  also includes a main memory  406 , preferably random access memory (RAM), and can also include a secondary memory  408 . Secondary memory  408  can include, for example, a hard disk drive  410  and/or a removable storage drive  412 , representing a floppy disk drive, a magnetic tape drive, an optical disk drive, etc. Removable storage drive  412  reads from and/or writes to a removable storage unit  414  in a well-known manner. Removable storage unit  414 , represents a floppy disk, magnetic tape, optical disk, etc. which is read by and written to by removable storage drive  412 . Removable storage unit  414  includes a computer usable storage medium having stored therein computer software and/or data. 
     In alternative embodiments, secondary memory  408  can include other similar means for allowing computer programs or other instructions to be loaded into computer system  400 . Such means can include, for example, a removable storage unit  422  and an interface  420 . Examples of such can include a program cartridge and cartridge interface (such as that found in video game devices), a removable memory chip (such as an EPROM, or PROM) and associated socket, and other removable storage units  422  and interfaces  420  which allow software and data to be transferred from the removable storage unit  422  to computer system  400 . 
     Computer system  400  can also include a communication interface  424 . Communication interface  424  allows software and data to be transferred between computer system  400  and external devices. Examples of communication interface  424  include, but are not limited to a modem, a network interface (such as an Ethernet card), a communications port, a PCMCIA slot and card, etc. Software and data transferred via communication interface  424  are in the form of signals which can be electronic, electromagnetic, optical or other signals capable of being received by communication interface  424 . These signals  426  are provided to communications interface via a channel  428 . This channel  428  carries signals  426  and can be implemented using wire or cable, fiber optics, a phone line, a cellular phone link, an RF link and other communications channels. Moreover, computer system  400  can be directly controlled or programmed by a main comminution computer (not shown) via communication interface  424 . 
     Data concerning the material being comminuted may be collected by known optical, resonant and/or thermal imaging apparatus. Particularly, the use of data collection apparatus that can be used to detect color variation in a tire being comminuted so as to redirect the lance as rubber removal exposes the interior white layer of the tire. The collected data is then processed by computer system  400  via communication interface  424 . Computer system  400  can be programmed to determine the appropriate liquid jet distribution based on this data so as to control lance  110  and the comminution process. 
     In this document, the terms “computer program medium” and “computer usable medium” are used to generally refer to media such as removable storage device  412 , a hard disk installed in hard disk drive  410 , and signals  426 . These computer program products are means for providing software to computer system  400 . 
     Computer programs (also called computer control logic) are stored in main memory and/or secondary memory  408 . Computer programs can also be received via communication interface  424 . Such computer programs, when executed, enable the computer system  400  to perform the features of the present invention as discussed herein. In particular, the computer programs, when executed, enable the processor  404  to perform the features of the present invention, such as controlling the comminution process by varying the liquid jet distribution on the material being comminuted. Accordingly, such computer programs represent controllers of the computer system  400 . 
     In an embodiment where the invention is implemented using software, the software can be stored in a computer program product and loaded into computer system  400  using removable storage drive  412 , hard drive  410  or communication interface  424 . The control logic (software), when executed by the processor  404 , causes the processor  404  to perform the functions of the invention as described herein. 
     In another embodiment, the present invention is implemented primarily in hardware using, for example, hardware components such as application specific integrated circuits (ASICs). Implementation of the hardware state machine so as to perform the functions described herein will be apparent to persons skilled in the relevant art(s). 
     In yet another embodiment, the invention is implemented using a combination of both hardware and software. 
     EXAMPLE 
     In one example, a tire may be comminuted by the comminution apparatus operating in the following ranges: 
     n 1 =5 rev./sec. 
     n 2 =10 rev./sec. 
     L=6-8 in. 
     S=3-10 in. 
     wherein r 1 =1″, r 2 =4″ and the internal diameter of the outer cylindrical tube is 10″. The tire may be separated into its constituent parts and comminuted into pieces with an average mesh size of between 40 to 200. 
     While various embodiments of the present invention have been described above, it should be understood that they have been presented by way of example, and not limitation. It will be apparent to persons skilled in the relevant art that various changes in form and detail can be made therein without departing from the spirit and scope of the invention. Thus the present invention should not be limited by any of the above-described exemplary embodiments, but should be defined only in accordance with the following claims and their equivalents. All cited patent documents and publications in the above description are incorporated herein by reference.