Abstract:
The present invention is a system and method for cleaning the interior and exterior surfaces of an animal intestine. The system includes a carrier for holding and transporting sections of the intestine along a closed-path track. A vertically disposed tube, located at a point along the track, is connected to a cleaning fluid supply and directs a spray of cleaning fluid at the exterior surfaces. A cleaning nozzle, located at a point along the track, directs cleaning fluid into an interior of the intestine.

Description:
CROSS-REFERENCE TO RELATED APPLICATION(S) 
     None. 
     BACKGROUND OF THE INVENTION 
     The present invention relates to a system and method for cleaning animal intestines. More particularly, it relates to a system for cleaning both the interior surface and the exterior surface of an extracted animal intestine using a washing action provided by a cleaning fluid. 
     In the slaughter of mammalian or red-meat animals, the primary meat and meat products are derived from the animal&#39;s skeletal muscles (i.e., those muscles that are attached to the skeleton and function to facilitate movement and support the weight of the animal). A number of other parts of the carcass are either consumed directly by people or used in the production of other foods. These portions of the carcass are often referred to as “offal.” Various types of red-meat slaughter animals include beef or bovine (e.g., cattle, steers, heifers, cows, bulls, and buffalo), pork or porcine (e.g., sows, gilts, barrows, boars, and pigs), and ovine (e.g., sheep and lamb). Typical beef offal includes the stomach, heart, brains, tongue, liver, kidneys, intestines, and mesentery (the folds of the peritoneum that connect the intestines to the dorsal abdominal wall). Typical pork offal includes the liver, kidney, brains, head, and intestines. Also, the wall of the intestine, with the inner lining (commonly referred to as the “mucosa”) removed, is used for packaging of sausages. 
     The present invention is directed to a system for cleaning the intestines, including both the small and large intestines, of these various red-meat slaughter animals, so that the intestines are suitable for human consumption. The intestine is a generally soft, tubular element, which extends from the stomach to the anus. The small intestines of various red-meat animals vary in length from about 15 feet to about 120 feet. The small intestines of cattle, for example, typically extend 80 feet to 120 feet, more typically from 100 feet to 110 feet, while the small intestines of hogs typically extend 15 feet to 18 feet. These animal intestines are generally extracted from the carcass of the dead animal during the slaughtering process. When extracted, the intestines generally remain attached to the mesentery and are disposed in a sinuous configuration. The intestines typically have connective tissue, fat tissue, and glands attached to an exterior surface, which must be removed prior to human consumption. 
     In a live red-meat animal, the intestines receive food (also referred to as “ingesta”) from the stomach, which is passed along the length of the intestine so that nutritional components of the food can be absorbed into the animal&#39;s blood stream. The unabsorbed portion of the food is discharged from a distal end of the intestine as digesta or fecal matter. Intestines which are harvested from the carcasses of red-meat animals during slaughtering contain some amount of digesta or fecal matter, which must be removed prior to human consumption. 
     One common food product made from animal intestines is “chitterlings,” which are made from hog intestines. Many devices for cleaning chitterlings are known in the prior art, including those disclosed in U.S. Pat. No. 3,509,593 to DeMoss and U.S. Pat. No. 5,820,453 to Burke. These devices operate by passing the chitterling over a tubular element having a nozzle for spraying water onto the interior surface to remove a portion of the fecal matter. In commercial cleaning operations, the chitterlings are then commonly slit longitudinally and cleaned further using a centrifugal or agitating washing action. Finally, the chitterlings are then commonly passed through a hand-cleaning and inspection station for further cleaning. 
     In Hispanic cultures, “tripas” are prepared from the small intestines of slaughtered red-meat animals. In European and Hispanic cultures intestines are used for sausage skin or casing. In both of these applications, the intestines must be properly cleaned such that they are suitable for human consumption. A device for washing tripas is disclosed in U.S. Pat. No. 6,083,096 to Carrillo. 
     The prior art systems and methods for cleaning animal intestines are labor-intensive and require much human intervention. This slows the cleaning process to below commercial chain speeds in a meat processing facility. 
     There is a need in the art for a system and method of removing ingesta and other undesirable particles from the surfaces of an animal intestines at commercial chain speeds (300 head per hour or more). There is a further need in the art for a device capable of cleaning the animal intestines without causing structural damage to the intestine, including the inner lining or mucosa of the intestine. 
     BRIEF SUMMARY OF THE INVENTION 
     The present invention, in one embodiment, is a device for cleaning an inner surface and an outer surface of a section of an animal intestine. In this embodiment, the device includes a carrier for supporting at least one of the sections and providing a connection to the inner surface. The device further includes a track for guiding and supporting the carrier, the track configured in a closed-loop. The device includes at least one vertically disposed tube having a plurality of orifices for directing a fluid at the outer surface. At least one nozzle is located along the elevated portion of the track and is adapted to direct the fluid into the connection of the carrier. 
     The present invention, in another embodiment, is a method of cleaning an interior surface and an exterior surface of animal intestines. In this embodiment, the method includes attaching the animal intestines to a carrier adapted to guide the animal intestines along a track and to allow access to the interior surface. The method includes elevating the carrier until the animal intestines hang vertically above ground level and impinging a spray of cleaning fluid onto the exterior surface of the plurality of animal intestines. The method also includes introducing a flow of cleaning fluid into the interior surface of the plurality of animal intestines through the carrier. 
     While multiple embodiments are disclosed, still other embodiments of the present invention will become apparent to those skilled in the art from the following detailed description, which shows and describes illustrative embodiments of the invention. As will be realized, the invention is capable of modifications in various obvious aspects, all without departing from the spirit and scope of the present invention. Accordingly, the drawings and detailed description are to be regarded as illustrative in nature and not restrictive. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a side view of an intestine washing system according to one embodiment of the present invention. 
     FIG. 2A is a sectional view of a nozzle assembly of the carrier of FIG. 2B, according to one embodiment of the present invention 
     FIG. 2B is a front view of a carrier, for use with the intestine washing system, according to one embodiment of the present invention. 
     FIG. 3 is a top view of a top section of the intestine washing system, shown in FIG. 1, according to one embodiment of the present invention. 
     FIG. 4 is a side view of an intestine washing system according to a second embodiment of the present invention. 
     FIG. 5 is a top view of a top section of the intestine washing system, shown in FIG. 4, according to one embodiment of the present invention. 
    
    
     DETAILED DESCRIPTION 
     FIG. 1 shows a side view of an intestine washing system  10  according to one embodiment of the present invention. As shown in FIG. 1, the system  10  includes a base  16 , a frame assembly  18 , an outer track  20 , an inner track  21 , a lift drive chain  22 , a return drive chain  24 , and a carrier  25 . As shown in FIG. 1, the base  16  is connected to and supports the frame assembly  18  above ground level. In one embodiment, the base  16  supports the frame assembly  18  at a level of 3 to 4 feet off the ground for the convenience of an operator  26 , who must connect intestine sections or product  27  to the trolley or carrier  25 . The frame assembly  18 , in one embodiment, is constructed from steel, although structural members of any type can be used. 
     The frame assembly  18  supports the outer track  20  and the inner track  21 , which together define a closed travel path of the carrier  25 . In one embodiment, the outer track  20  and the inner track  21  are constructed from metal rods, such as steel. The outer track  20  and the inner track  21  are generally coplanar and maintain a constant spacing or separation adapted to support the carrier  25 , as further discussed below. 
     The lift drive chain  22  is attached to the frame assembly  18  by a set of sprockets or drive plates  28 . The tension in the lift drive chain  22  is adjustable by the tension assembly  30 , and the lift drive train  22  is driven by an electric lift motor  32 . In the embodiment illustrated in FIG. 1, the electric lift motor  32  is mounted to the frame assembly  18 . The return drive chain  24  is also connected to the frame assembly  18  through sprockets or drive plates  34 . The tension in the return drive chain  24  is adjustable by the tension assembly  36 , and the return drive chain  24  is driven by an electric return motor  37 . In the embodiment illustrated in FIG. 1, the electric return motor  37  is mounted to the base  16  of the intestine cleaning system  10 . 
     A release mechanism  38  is located along the return drive chain  24 , as shown on the right-hand side of FIG.  1 . The release mechanism  38  operates to release product  27 , after it has been cleaned. The lift drive chain  22  and the return drive chain  24  function to drive the carrier  25  along the travel path defined by the outer track  20  and the inner track  21 . A container  39 , supported by the base  16 , is located near a vertically descending portion of the tracks  20 ,  21  (shown near the right-hand side of FIG. 1) for collection of the product after it has been cleaned. 
     FIG. 2A is a front view of the carrier  25 , according to one embodiment of the present invention. As shown in FIG. 2A, the carrier  25  includes a set of nozzle assemblies  42   a ,  42   b ,  42   c ,  42   d . While the embodiment shown in FIG. 2A includes four nozzle assemblies  42 , other embodiments may include any number of such nozzle assemblies, including fewer nozzle assemblies  42  and more nozzle assemblies  42 . As further shown in FIG. 2A, the carrier  25  includes wheels  44   a ,  44   b  and a carrier body  46 . The nozzle assemblies  42  are connected to and pass through the carrier body  46 . The carrier body  46  is rotatably coupled to the wheels  44   a  and  44   b , such that the nozzle assemblies  42  remain oriented perpendicular to the ground, while the carrier  25  traverses the tracks  20 ,  21 . In other words, the body  46  of the carrier  25  is free to pivot with respect to the wheels  44   a  and  44   b  of the carrier  25 . In the embodiment shown in FIG. 2A, the wheels  44   a  and  44   b  include generally central V-shaped grooves adapted to mate with the rods of the outer track  20  and the inner track  21 . In one embodiment, the wheels  44   a ,  44   b  are polymer wheels, as known in the art, which do not require lubrication. 
     FIG. 2B is a sectional view of one of the nozzle assemblies  42 . As shown in FIG. 2B, the nozzle assembly  42  includes a cylindrical nozzle  48 , having a tapered distal tip  50 . The cylindrical nozzle  48  is mounted to and passes through a body  52 . The nozzle assembly  42  further includes an annular ring  54  coupled to the body  52  by support cylinders  56   a  and  56   b . Cylinder  56   b  includes a notch  58  for receiving a latch  60 . The support cylinders  56   a ,  56   b  are spring-loaded such that they are biased in a downward direction (toward the tapered distal tip  50 ). As illustrated in FIG. 2B, the annular ring  54  includes a tapered aperture through its center. The aperture is tapered such that it is wider on a face closer to the tapered distal tip, and narrower on a face closer to the body  52 . This taper feature facilitates passage of the product  27  through the aperture, which can then be locked in place, as further described below. 
     FIG. 3 shows a top view of a top portion of the intestine washing system  10  according to one embodiment of the present invention. As shown in FIG. 3, the system  10  generally includes two sets of components disposed in generally parallel planes for supporting and driving the carrier  25 . In the top portion of the system  10 , the support and guiding of the carrier  25  is performed by the inner track  21  (further illustrated near the top of FIG.  1 ). 
     As shown on the left-hand side of FIG. 3, the lift drive chain  22  includes a rear lift drive chain  22   a  and a front lift drive chain  22   b  for driving a first end and a second end of the carrier  25 . The lift drive chains  22   a ,  22   b  are disposed in generally parallel planes. In another embodiment of the present invention, only one lift drive chain  22  is employed. The lift drive chains  22   a ,  22   b  terminate at the corresponding sprockets or drive plates  60   a  and  60   b . As also shown in FIG. 3, the inner track  21  includes a rear inner track  21   a  and a front inner track  21   b  for supporting the first wheel  44   a  and the second wheel  44   b  of the carrier  25  as it travels along the top portion of the intestine washing system  10 . As shown near the center of FIG. 3, the top portion includes a free trolley section  61  where the carrier is supported and guided by the inner tracks  21   a ,  21   b , but is not driven. As shown near the right-hand side of FIG. 3, the top portion includes a portion of the return drive chain  24 , which includes a rear return drive chain  24   a  and front return drive chain  24   b  disposed in generally parallel planes. The return drive chain  24  originates at drive plates  62   a  and  62   b . The free trolley section  61  extends from the drive plates  60   a ,  60   b  to the drive plates  62   a ,  62   b.    
     FIG. 3 also shows a top view of fluid supply pipes  64   a  and  64   b . The fluid supply pipes  64   a ,  64   b  extend generally downward from the inner tracks  21   a ,  2   ab  in a direction substantially perpendicular to the plane of travel of the carrier  25 . The fluid supply pipes  64   a ,  64   b  include a plurality of generally equally spaced nozzles along their length. The nozzles are configures to generate the spray pattern  66  shown in FIG. 3, which acts to clean an exterior surface of product, as explained in greater detail below. In one embodiment of the present invention, the fluid supply pipes  64   a ,  64   b  supply water to perform cleaning of the outer surface of the product  27 . In other embodiments, other cleaning fluids known to those of skill in the art are used to perform the cleaning operation. 
     During operation of the intestine washing system  10  (shown in FIG.  1 ), the operator  26  takes a section of product  27  and slides it over the tapered distal tip  50  of the nozzle  48 , through the tapered aperture of the ring (shown in FIG.  2 ). The tapered aperture is wider at a proximal face (closer to the tapered distal tip  50 ) and narrows as it moves toward a distal face. This taper facilitates insertion of the product  27 . Once the product  27  is inserted through the aperture, the operator  26  pushes up the annular ring  54 , along the support cylinders  56   a ,  56   b , until the latch  60  engages the notch  58 , thereby securing the annular ring  54  in place. At this point, the product  27  is secured in place between the annular ring  54  and the tapered aperture of the nozzle  48 . The operator then repeats this process for each of the nozzles  42   a ,  42   b ,  42   c ,  42   d , such that four sections of product  27  are connected to the carrier  25 . 
     Once all sections of product are attached to the carrier  25 , the operator  26  moves the carrier  25  forward along the tracks  20 ,  21  until it engages the lift drive chain  22 . The lift drive chain  22  then raises the sections of product  27  to the top of the intestine cleaning system  10  (the area shown in FIG.  3 ), where the carrier  25  is released from the lift drive chain  22  onto a proximal end of the free trolley section  61 . 
     In one embodiment of the present invention, the product  27  is pre-cut prior to introduction to the intestine washing system  10 , using one of the techniques known in the art. In another embodiment of the present invention, the product  27  is not pre-cut, but instead cutting is performed by the intestine cleaning machine, when the carrier  25  reaches an appropriate height. 
     The carrier  25  will remain in a position adjacent to the distal end of the lift drive chain  22  until a second carrier  25  reaches the top of the intestine cleaning system  10  and indexes the carrier  25  one position forward (toward the right, as shown in FIG.  1 ). Each successive carrier  25  reaching the top portion entering the free trolley section  61  will index the prior carriers  25  further down the tracks  21   a ,  21   b  of the free trolley section  61 . 
     While positioned at the top of the intestine cleaning system  10 , as shown in FIG. 3, the carrier  25  is supported by the inner tracks  21   a ,  21   b , and it spans the distance between the tracks such that the sections of the intestine hang down generally perpendicular to the tracks  21   a ,  21   b . As the carrier  25  moves along the free trolley section  61 , its exterior surface is cleaned by a spray of cleaning fluid  66 , from the fluid supply pipes  64   a ,  64   b , impinging on the exterior surface. The spray of fluid, according to one embodiment of the present invention, is shown in FIG.  3 . As the carrier  25  progresses along the free trolley section  61 , the fluid spray  66  impinges upon different portions of the exterior surface of the product  27  so that, by the time the carrier  25  has completely traversed the free trolley section  61 , the exterior surface will be free of fecal matter and other contaminants. In one embodiment of the present invention, the fluid supply pipes  64   a ,  64   b  carry water charged to a pressure of about 60 to about 80 psi. In one embodiment, the fluid supply pipes  64   a ,  64   b  include nozzles adapted to spray fluid in a fan at angles of about 15 to about 60 degrees from a line extending between the pipes, as shown in FIG.  3 . In one embodiment the intestine cleaning system  10  includes controls to regulate the pressure of the fluid in the fluid supply pipes  64   a ,  64   b.    
     At one point along the free trolley section  61 , the nozzle assemblies  42   a ,  42   b ,  42   c ,  42   d  of the carrier  25  align with corresponding fluid supply nozzles located above the tracks  21   a ,  21   b  along the free trolley section  61 . At this point, the cleaning fluid is introduced into the interior of the sections of product  27  through the nozzles  48  in the nozzle assemblies  42   a ,  42   b ,  42   c ,  42   d  by injecting the fluid into the orifices located at the tops of the nozzles  48 . The cleaning fluid is then driven by gravitational forces through an interior lumen of the sections of product  27  and will discharge out a distal end of the sections into a collection trough below, where it can be disposed of properly. This cleaning fluid will scrub interior walls of the sections of intestine and remove any digesta and fecal matter therein. This waste material will travel with the cleaning fluid into the collection trough below for disposal. In one embodiment of the present invention, the fluid supply nozzles supply a free flow of water for about 8 to about 16 seconds. In another embodiment, water is allowed to flow through the interior lumen of the product  27  until the water is exiting the product  27  appears clear. 
     Once the carrier  25  reaches the distal end of the free trolley section  61 , it is engaged by the return drive chains  24   a ,  24   b , and is guided by the outer track  20  and the inner track  21  in a generally downward direction. As the carrier  25  travels downward, the product  27  enters the container  39 , so that it can be removed for further processing or packaged. When the carrier  25  reaches the release mechanism  38 , the release mechanism  38  contacts and manipulates the latch  60 , which releases the support cylinders  56   a,    56   b.  This, in turn, releases the rings  54  of the nozzle assemblies  42   a ,  42   b ,  42   c ,  42   d . The rings  54  are then driven downward by the spring action, thereby releasing the sections of product  27 . In one embodiment, this release point is located about 3 feet above the container  39 . 
     In one embodiment, the container  39  is a stationary container or tray that accepts the clean product  27 . In another embodiment, the container  39  is mounted on an oscillating driver so that the product  27  is placed into the container  39  in a serpentine fashion. This places the product  27  in a configuration suitable for directly packaging for sale to the consumer. 
     When the carrier  25  reaches a bottom of the outer track  20 , the outer track  20  guides the carrier  25  along a lower section of the intestine cleaning system  10  back toward the operator  26 . In one embodiment, the lower section of the system  10  includes a carrier cleaning system for removing any contamination from the carrier  25 . In one embodiment, the carrier cleaning system is comprised of one or more nozzles for spraying a cleaning fluid onto the carrier as it travels along the bottom section. In one embodiment, the cleaning fluid is the same cleaning fluid used to clean the product  27 . In another embodiment, a more powerful cleaning fluid (such as a bleach) is used, followed by a water rinse of the carrier  25 . 
     Once the carrier  25  reaches the end of the release drive chain  24 , carrier  25  is released onto a free load section, where it awaits loading by the operator  26 . At this point, the carrier  25  has completed a full loop through the intestine cleaning system  10 , has been cleaned of contaminants, and is ready to complete a second cycle. 
     The system  10  of the present invention, in one embodiment, operates at a rate sufficient to clean sections of small intestines at typical commercial chain speeds of a meat processing facility. In one embodiment, the system  10  can keep pace with a meat processing line operating at about 300 head per hour. In one embodiment, two or more of the systems  10  are operated in parallel to provide each operator  26  with additional time to attach sections of product  27  to the carrier  25 . 
     FIG. 4 is a side view of an intestine cleaning system  80  according to a second embodiment of the present invention. As shown in FIG. 4, the intestine cleaning system  80  includes lift drive chain section  82 , a free trolley section  84 , a return drive chain section  86 , and a carrier accumulator  88 . The intestine cleaning system  80  further includes a carrier  90 , a fluid injector  92 , and a carrier release  94 . Each of the sections  82 ,  84 , and  86  are connected to a pair of continuous tracks that support wheels of the carrier. The intestine cleaning system  80  shown in FIG. 4 differs from the intestine cleaning system  10  shown in FIG. 1 in three main aspects. First, the intestine cleaning system  80  is designed for operation with a carrier adapted to carry only one intestine section (shown in FIG.  5 ). Second, the system  80  includes a collection tray  96  for gently laying down the intestine sections after cleaning. Third, the system  80  includes four fluid-cleaning tubes and corresponding sets of fluid spray nozzles, as shown in FIG.  5 . 
     FIG. 5 shows a top view of the intestine-cleaning system  80 , according to one embodiments of the present invention. The embodiment shown in FIG. 5 includes two parallel sets of tracks for guiding two carriers  90  in parallel. In other embodiments of the present invention, more tracks may be set up in parallel to carry more of the carriers  90 . FIG. 5 also shows an exterior cleaning system  98  according to one embodiment of the present invention. As shown in FIG. 5, the exterior cleaning system  98  includes four water supply pipes  100   a ,  100   b ,  100   c ,  100   d . Each of the water supply pipes  100   a ,  100   b ,  100   c ,  100   d  includes a plurality of spray nozzles located along its length and directed towards a center point of the cleaning system  98 . 
     During operation of the intestine cleaning system  80 , the operator selects a length of intestine and attaches it to the carrier  90 . The carrier  90  includes expandable jaws which engage an interior of the intestine and are released to expand and secure the section of intestine to the carrier  90 . The operator than places the carrier  90  onto the lift drive chain  82 , the carrier  90  moves onto the free trolley section  84 . The carrier  90  is moved along the free trolley section  84  when the next carrier  90  reaches the top of the lift drive chain. 
     As the carrier  90  moves from a proximal end to a distal end of the free trolley section  84 , the carrier  90  passes through the cleaning system  98 , as shown in FIG.  5 . As the carrier  90  moves through the cleaning system  98 , it is sprayed with cleaning fluid from the fluid supply pies  100   a ,  100   b ,  100   c ,  100   d . Also, when the carrier  90  reaches the position along the free trolley section  84  where the nozzle injector  92  is located, water is introduced into an interior of the intestine section through an orifice in the carrier  90 . cleaning fluid is allowed to pass through the interior surface of the intestine section until substantially all digesta and fecal matter is removed from the interior of the intestine. When the carrier  90  reaches a distal end of the free trolley section  84 , it engages the return drive chain  86 , and it begins a gradual descent. 
     As the carrier  90  descends along the return drive chain  86 , the intestine section is laid down on the tray  96 . When the carrier  90  reaches the release mechanism  94 , the intestine section is released from the carrier  90  and falls onto the tray  96 . As shown in FIG. 4, the initial segment of the return drive chain  86  has a relatively shallow slope and the tray  96  is rounded at a proximal end, such that the intestine section is laid down gently in a substantially extended configuration. The carrier  90  then travels along to the distal end of the return drive chain  86 , where it is cleaned for further use, and is placed on the carrier accumulator  88 , where it becomes available to the operator. Next, the intestine sections located on the collection trough  96  may be subjected to further processing or removed to a packaging area to be packaged. 
     In one embodiment of the present invention, the intestine-cleaning system  10  includes a release switch. In this embodiment, the operator causes the lift drive chain  22  to engage the carrier  25  by pressing the release button. In one embodiment, the release switch is placed near the operator&#39;s knee and is adapted to be activated by the operator&#39;s knee. This design allows the operator  26  to have control over when the carrier  25  engages the lift drive chain  22 . 
     Both of the intestine cleaning systems  10 ,  80  disclosed are capable of cleaning intestine sections at a sufficient rate to keep pace with a typical meat processing assembly line operating at about 300 head per hour. The specific rate of the systems  10 ,  80  will depend on the number of sections cleaned at one time and the rates at which the operator is able to properly mount intestine sections to the carrier. 
     Although the present invention has been described with reference to preferred embodiments, persons skilled in the art will recognize that changes may be made in form and detail without departing from the spirit and scope of the invention.