Abstract:
A multiple-use injection machine of the type used in food processing, is especially suited for selectively injecting treatment media into meat products including, inter alia, beef, pork, whole chickens and chicken parts. The treatment media is chose from a group including both liquid aqueous solutions utilized at normal ambient temperatures and normal operating pressures and a thermal treatment medium such as live steam at elevated temperatures and pressures. The multiple utilitarian capacity in a single injector machine is achieved by the use of bushings supporting the needles in their vertical position and supporting a seal in the manifold, but wherein the bushings are made of either a Polyetheretherketone material, or stainless steel, and the O-rings used for sealing are made of VITON brand heat resistant material or “TEFLON” brand

Description:
BACKGROUND OF INVENTION 
     1. Field of the Invention 
     This invention relates generally to machinery used in processing of beef, pork, whole chickens and chicken parts, and more particularly to an injection machine utilizing a specific bushing construction which may advantageously be used in machines for injecting various formulations and fluids, including marinade formulations, aqueous liquid solutions which may be corrosive, and for thermally conditioning food products with live steam at sufficiently high temperatures and pressures to insert sufficient thermal energy into the interior of the food product so that end point temperature meets Federal regulations. 
     2. The Prior Art 
     The prior art is exemplified by the practices of Stein-DSI, a business of FMC Food Technology. According to products sold to and used by customers of that company, machinery is provided wherein beef, pork, whole chickens, or chicken parts, are carried on a conveyor and are temporarily positioned under a press containing multiple hollow needles which are adapted to selectively receive a processing fluid under pressure. The press is operated to cycle up and down in a vertical path so that the points of the hollow needles penetrate the meat and inject the processing fluid into the interior portions of the meat. 
     In the current state of the art, the processing fluid is most often a marinade, i.e., a pickling liquid, or aqueous solution, usually of vinegar or wine with oil, herbs, spices etc. selected to steep the meat before cooking. 
     Such marinating operations are customarily performed on machines and equipment designed to inject liquid marinade which is relatively cool, for example, at or near room, or ambient, temperature. Thus, the machine function of meat penetration is performed with the use of hollow needles which can be reciprocated in a press which includes a manifold utilizing prior art sealing instrumentalities. Such seals can be fully effective only in the range of relatively low operating temperatures normally contemplated in such an operating environment. 
     However, in order to thermally treat food products with live steam at elevated temperatures and under pressure, such sealing means are completely unacceptable and are subject to failure, thereby rendering the machine ineffective for thermally conditioning purposes. 
     BRIEF SUMMARY OF THE INVENTION 
     The present invention contemplates the construction of an injection machine which utilizes a particularly effective combination of piercing needles and manifold parts in conjunction with a specific form of bushing construction performing two principal functions: (1) the bushing adequately supports the needle in its vertical position throughout a wide range of operating conditions, including thermal conditioning with live steam at elevated temperatures and, (2) the bushing supports an effective heat resistant seal to prevent leakage around the needle with which it is associated when used with live steam at elevated temperatures and under pressure. 
     Further, by virtue of the special constructions, featuring in one form of the invention, the use of bushing parts made of “POLYETHERETHERKETONE” (sometimes referred to by an abbreviation PEEK) and “O” ring seals made of “VITON,” (a registered trademark of DuPont Dow Elastomers L.L.C. for a heat resistant material made of synthetic rubber and rubber compositions) and featuring in another form of the invention, the use of bushing parts made of stainless steel and “O” ring seals made of “TEFLON,” (a registered trademark of E.I. DuPont De Nemours and Company for a chemical plastic compound with oil, water and stain repellant characteristics), the bushing constructions disclosed herein can be utilized with either conventional aqueous solutions such as marinade, or with corrosive solutions, at their normal usage temperatures, or with live steam at elevated temperatures in the order of about 350 degrees Fahrenheit and at increased pressures ranging from 15 to 55 pounds per square inch. 
     The structures thus provided allow the injector apparatus to exploit the characteristics of thermally pre-conditioning a food product, such as meat, to insure that the meat is fully cooked when processed in a large scale mass production processing environment. Live steam can be introduced into the manifold and injected with full and proper penetration of the meat so that elevated internal temperatures are achieved to promote full 100% bacterial kill in the final cooked meat product. 
     The sealing units provided in accordance with this invention are fully reliable with fluids at temperatures lower than the temperature of live steam, whether such fluids constitute gaseous fluids, corrosive solutions, or aqeous formulations such as marinade. Hence, the structures provided are universally applicable to food processing procedures in a wide range of application without necessitating duplication of large and expensive machinery. 
    
    
     BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING 
     FIG. 1 is a perspective view of an injection apparatus of the type in which the inventive features of the present invention find a particular utility. 
     FIG. 2 is a plan elevational view of the upper manifold member utilized in the present invention with a brine head connected thereto, and illustrating only a single row of needles in place for purposes of simplifying the drawing disclosure. 
     FIG. 3 is a cross-sectional view taken on the plane III—III of FIG.  2  and with a portion of a tray conveyor means added to illustrate the relationship of the injector machine press components with the needles in the upper position of the press stroke. 
     FIG. 4 is a view similar to FIG. 3 but showing the needles in the bottom position of the press down stroke and with the needles penetrating the flesh of the meat parts. 
     FIG. 5 is a fragmentary cross-sectional view showing details of one form of the bushing construction of the present invention particularly adapted for achieving thermal injection of live steam for thermally conditioning the interior of meat products, as well as for injecting treatment medium at normal ambient temperatures. 
     FIG. 6 is a fragmentary cross-sectional view showing a different form of the invention, but which is also suitable for dual utility, i.e., the thermal treatment of a food product with live steam at elevated temperatures and under pressure, or the injection of treatment medium at normal ambient temperatures, including corrosive solutions. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring to FIG. 1 of the drawings, there is shown an exemplary form of a food processing apparatus constituting an injection machine and embodying the improved features contemplated by the present invention and by means of which the novel steps of the methodology of the present invention may be practiced. 
     The advent of fast food restaurants has been accompanied by the development of food processing procedures designed to insure uniform high quality and good taste which will meet the expectations of consuming customers. Marination, or the injection of a marinade into beef, pork, or chicken meat, for example, is currently one of the standard practices of the food procsessing industry. 
     One of the problems confronting the industry is to insure that the chicken meat, for example, whether whole chickens, or chicken parts, is fully cooked to the extent required by government regulations, when processed in a mass production facility before packaging and shipping to a retail facility. Prior to cooking, the typical internal temperature of unfrozen, bone-in chicken parts is in the range of 40 to 45 degrees Fahrenheit. The internal temperatures must be raised to at least 160 degrees to measure up to the U.S.D.A. minimum temperature requirement with a poultry product to insure 100% bacterial kill. Comparable government regulations exist for other foods with respect to minimum lower end point temperatures. 
     To insure compliance with Federal regulations, food processors generally try to achieve a final internal temperature of 185-190 degrees Fahrenheit, so that all of the chicken parts on the line will be above the specified minimum before the meat is moved on to further stages of cooking, or thermal processing. 
     The particular improvement to which this disclosure is directed is the processing fluid injection apparatus shown generally at  10 . While it should be understood that the principles of the present invention are applicable to any food product to which the food processing steps herein disclosed are applicable, we have described the inventive features as applied to an injection machine for inserting a treatment medium into a food product, but especially a meat food product, for example, such as chicken. Thus, chicken meat in the form of whole chickens, or chicken parts, labeled “C” are loaded on a tray-compartmented conveyor means  11  having a plurality of separate trays  12 . The conveyor means  11  is driven by a power assisting means depicted schematically, such as a motor means  13  controlled by pre-settable control means  14 . The pre-settable control means  14  is of the type that can be selectively programmed so that the trays  12  are successively stepped into and through a penetrating station which includes a press which is also controlled by the pre-settable control means  14 . The press and the control means are enclosed within a closure designated at  16 . It will be understood that the power assisting means would be part of the mechanism which is also enclosed inside of the enclosure  16  of the machine  10 . 
     Turning now to FIG. 2-4, a press mechanism is provided inside of the enclosure  16 . In accordance with this invention, the press mechanism includes a manifold  20 , the details of which are shown in FIGS. 2 and 3. The manifold  20  has an upper manifold part  21  formed with a plurality of needle openings  22 . A lower manifold part  23  is connected thereto and together therewith forms a manifold chamber  24 . The lower manifold part  23  is similarly provided with a corresponding plurality of needle openings  25 . The needle openings  22  and  25  are in precise axial alignment with one another and are disposed in an array of openings arranged in rows and columns on close centers to form a rectangular pattern generally co-extensive with the area of a tray  12  on the conveyor means  11 . 
     A head means  26  is selectively supplied with a treatment medium. For example, a high output liquid pump P depicted diagrammatically drives a solution or formulation to the head means  26 . Because of such function, the head means  26  is oftentimes referred to using the sobriquet of “brine head.” In accordance with this invention, the so-called brine head  26  is also selectively connected with a source of pressurized high temperature steam “S” and is supplied with live steam at a temperature in the order of about 350 degrees Fahrenheit (F) and at a pressure ranging from 15 to 55 pounds per square inch (PSI). The brine head  26  forms a conduit  27  which carries the treatment medium, whether it be fluid, liquid, or live steam, to a passage  28  leading to the manifold chamber  24 . 
     For each pair of needle openings  22  and  25  in the manifold  20 , there is a hollow needle  30 . The needles  30  are carried on the upper manifold part  21  and each needle  30  extends downwardly through its own opening  22  through the manifold chamber  24  and through its mating aligned opening  25  in the lower manifold part  23 . The needles  30  are of uniform length and extend downwardly through a stripper plate  40  having plural matching openings  41 . The stripper plate  40  acts to strip the meat “C” from the needles  30  when they are retracted on the up stroke of the press. 
     Actuating means (not shown) are provided to cycle the press including the manifold  20  and the needles  30  carried thereby through a vertical stroke which extends between an upper position shown in FIG. 3 and a lower position shown in FIG.  4 . Thus, in the position of FIG. 3, the manifold  20  is spaced above the stripper plate  40 . The needles  30  have sharpened points shown at  31  which are positioned in register with one of the trays  12  on the conveyor means  11 , but at a level above the contents of the tray  12 . 
     In FIG. 4, the actuating means has moved the press with its components including the manifold  20  and the needles  30  vertically in the direction of the arrows “A” (FIG. 4) to the lower position wherein the points  31  of the needles  30  have penetrated the contents of the tray  12 , in this instance, the flesh of the chicken meat part, or chicken “C.” 
     As shown in FIG. 6, each needle  30  has an opening  33  placing the manifold chamber  24  in communication with an elongate centrally disposed axial passage  34  within the interior of the needle  30 . At the lower end of the needle  30 , but inwardly of the point  31  of the needle  30 , there is formed a plurality of openings  35 . When the points  31  of the needles  30  penetrate the meat “C” and the needles  30  pass into and through the meat “C” the the pressurized fluid medium supplied to the manifold chamber will flow into the needles  30  and will be inserted into the interior of the meat “C.” A press provided with the manifold  20  of the present invention reciprocates four hundred and eighty eight independent needles  30  disposed on close centers so that uniform distribution of treatment medium throughout the food product  30  being penetrated and injected is insured. 
     In accordance with the principles of the present invention, a special form of bushing construction is provided to support each needle  30  in its vertical position, and to support a seal in the upper and lower manifold parts  21  and  23  and to thereby prevent leakage of the treatment medium around the needle  30 . 
     Referring to FIGS. 5 and 6, each opening  22  in the upper manifold part  21  is counter-bored in the upper surface of the manifold part  21  to provide a first recess  50  extending radially outwardly of and concentric to the vertical axis of the opening  22 . The counter-bored recess  50  terminates in a radial shoulder  51  spaced outwardly of the manifold chamber  24 . A second recess  52 , also formed by counter-boring, extends radially outwardly of the vertical axis of the opening  22  and terminates in a radial shoulder  53 . 
     Similar provisions are made in the lower surface of the lower manifold part  23 . Each opening  25  in the lower manifold part  23  is counter-bored in the lower surface of the manifold part  23  to provide a first recess  60  extending radially outwardly of and concentric to the vertical axis of the opening  25  and terminating in a radial shoulder  61  spaced outwardly of the manifold chamber  24 . A second recess  62 , also formed by counter-boring, extends radially outwardly of the vertical axis of the opening  25  and terminates in a radial shoulder  63 . 
     In one form of the invention, a bushing construction takes the form of two separate bushing parts. The first bushing part  70  is a cylinder  71  outwardly flanged as at  72  and having an outer wall  73  with a diametral dimension complemental to the inner diameter of the recess  50 . The walls of a center axis opening  74  closely adjoin the needle  30 . In order to securely lock the bushing construction in assembly with the manifold  20 , the outer wall  73  and the inner diameter of the recess  50  are threaded and are threadedly engaged with one another. 
     The second bushing part  75  is a cylinder  76  inwardly flanged as at  77  and having an outer wall  78  with a diametral dimension greater than the opening  22  and less than the inner diameter of the recess  50 . 
     Each of the first and second bushing parts  70  and  75  is made of 20% to 30% glass reinforced “POLYETHERETHERKETONE,” (PEEK) a material which exhibits excellent mechanical properties, thermal properties and is chemically resistant to acids, alkalies and to all organic solvents. It can be fabricated in molded parts and is especially suitable for high-temperature environments. 
     An O-ring seal  80  made of “VITON,” brand temperature resistant material is shown seated on the shoulder  53  and establishes a seal between the first bushing part  70  and the upper manifold part  21 . The second bushing part  75  seats on the shoulder  51  and receives an O-ring seal  81  also made of “VITON” brand material to establish a seal with the needle  30  and the upper manifold part  21 . “VITON” material exhibits excellent heat resistant characteristics and is ideally suited for use in high temperature environments. 
     Comparable bushing parts  70  and  75  and O-rings  80  and  81  are placed in the counter-bored openings of the lower manifold part  23  in the same manner and for the same purposes as those described and numbered in connection with the upper manifold part  21 , and the description and numbering of the parts need not be repeated. 
     The bushing construction thus provided performs well in the environment of a thermal conditioning method environment for treating food products. Live steam at a temperature in the order of about 350 degrees F. and at pressure in the range of 15 to 55 psi is injected into chicken flesh with great efficiency and effectiveness without any deteriorative effect in the functional performance of the bushing construction. Accordingly, the versatility of a single injection machine  10  can be greatly enhanced with the use of the press components of the present invention. 
     In another form of the invention shown in FIG. 6, a first bushing part  70   a  and a second bushing part  75   a  are made of stainless steel. In structural configuration, both are quite similar in size and shape to their counter-part bushing parts  70  and  75 . However, referring to FIG. 6 it will be noted than an outwardly extending flange  72   a  seats directly on a shoulder  53   a  and an axially extending center opening  74   a  is enlarged to receive a bushing insert sleeve  90  made of “TEFLON.” A pair of O-rings are shown at  80   a  and  81   a , each made of “TEFLON.” They are inserted at the top of the bushing part  70   a  and in the recess provided by the flange of the second bushing part shown at  75   a . As with the first bushing part  70 , the bushing part  70   a  has an outer wall  73   a  which is threaded to threadedly engage the correspondingly threaded inner wall of the recess  50   a.    
     Again, comparable parts are utilized in the lower manifold part  23  and may be referred to with similar reference numbers for the sake of convenience. 
     In both forms of the invention, the apparatus utilizing the bushing constructions of this disclosure has the ability of greatly expanded utility since it be used safely and effectively in marinating meat with formulated aqueous solutions at conventional operating temperatures, or it can be used for temperature conditioning meat and/or other food products with high temperature live steam at 350 F. and 15-55 psi. 
     Assuming that a user has employed the machine  10  for normal marinating operations with a formulated aqueous solution of marinade at normal temperatures, and wishes to use the machine  10  for temperature conditioning meat products, the machine  10  may be purged of marinade, if necessary or desirable, and then connected to a source of live steam as the source “S” and the temperature conditioning function, or methodology, will be carried out effectively and reliably. 
     While we have identified POLYETHERETHERKETONE and VITON brand material as presently available and satisfactory for the purposes of our invention, it should be understood that if other engineered materials displaying equivalent characteristics are, or become available, substitution of such equivalent materials would not be a departure from the spirit of this invention. 
     Although minor modifications might be suggested by those artisans skilled in the art, it should be understood that we wish to embody within the scope of the patent warranted hereon all such modifications as reasonably and properly come within the scope of our contribution to the art.