Auger type poultry chillers with enhanced hanger bearing configurations and related assemblies
11083205 · 2021-08-10
Assignee
Inventors
Cpc classification
A23B4/062
HUMAN NECESSITIES
A22B5/0076
HUMAN NECESSITIES
B65G33/04
PERFORMING OPERATIONS; TRANSPORTING
F28F5/06
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F25D13/065
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
International classification
F28F5/06
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
B65G33/32
PERFORMING OPERATIONS; TRANSPORTING
B65G33/04
PERFORMING OPERATIONS; TRANSPORTING
F25D13/06
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
Abstract
A poultry chiller includes a tank and an auger rotatably held in the tank. The auger includes a first auger section and a second auger section. The first auger section includes a first auger shaft and a first auger flight. The first auger flight includes a first helical portion on the first auger shaft and a first flight extension that extends away from the first helical portion. The second auger section includes a second auger shaft coupled to the first auger shaft and a second auger flight. The second auger flight includes a second helical portion on the second auger shaft and a second flight extension that extends away from the second helical portion. The chiller includes a hanger bearing assembly between the first and second auger sections and extending to an upper portion of the tank.
Claims
1. A poultry chiller comprising: an elongated tank; an auger rotatably held lengthwise in the tank and defining a longitudinal axis, the auger comprising: a first auger section comprising a first auger shaft and a first auger flight that extends radially away from the first auger shaft, the first auger flight comprising a first helical portion that is helically disposed on the first auger shaft and a first flight extension that extends approximately circumferentially away from the first helical portion; and a second auger section comprising a second auger shaft and a second auger flight that extends radially away from the second auger shaft, the second auger flight comprising a second helical portion that is helically disposed on the second auger shaft and a second flight extension that extends approximately circumferentially away from the second helical portion; a coupling shaft coupling a first coupling end of the first auger shaft and an adjacent second coupling end of the second auger shaft; and a hanger bearing assembly comprising a bearing assembly supporting the coupling shaft, a support member coupled to an upper portion of the tank, and a hanger extending between the bearing assembly and the support member; wherein the first auger flight overhangs the first coupling end of the first auger shaft and the second auger flight overhangs the second coupling end of the second auger shaft.
2. The poultry chiller of claim 1 wherein, as the auger rotates in the tank, the hanger passes through an axial gap defined by the first and second flight extensions, and wherein the axial gap has a greater axial length at the first and second auger shafts than at outer edges of the first and second flight extensions.
3. The poultry chiller of claim 2 wherein the axial gap comprises a first portion extending radially away from the first and second auger shafts and a second portion extending radially away from the first portion of the axial gap to the outer edges of the first and second flight extensions, and wherein the axial length of the first portion of the axial gap decreases from the first and second auger shafts to the second portion of the axial gap.
4. The poultry chiller of claim 1 wherein, as the auger rotates in the tank, a leading edge of the second flight extension and an engagement edge of the hanger are configured to urge product caught therebetween radially outwardly toward an outer edge of the first auger flight and/or an outer edge of the second auger flight.
5. The poultry chiller of claim 4 wherein the engagement edge of the hanger is arcuate.
6. The poultry chiller of claim 4 wherein the leading edge of the second flight extension is substantially straight and defines an offset angle with a projection extending radially away from the longitudinal axis of the auger.
7. The poultry chiller of claim 6 wherein the offset angle is at least 20 degrees.
8. The poultry chiller of claim 4 wherein a lower surface of the support member and the outer edge of the first auger flight and/or the outer edge of the second auger flight define an opening that is sized to allow product urged radially outwardly to pass therethrough.
9. The poultry chiller of claim 1 wherein a trailing edge of the first auger flight and a leading edge of the second auger flight define a circumferential gap therebetween.
10. The poultry chiller of claim 9 wherein the circumferential gap varies in width from the first and second auger shafts to outer edges of the first and second auger flights.
11. The poultry chiller of claim 10 wherein: the leading edge and the trailing edge meet or overlap at one of the first and second auger shafts and the outer edges of the first and second flights; and the leading edge and the trailing edge are spaced apart at the other one of the first and second auger shafts and the outer edges of the first and second flights.
12. The poultry chiller of claim 1 wherein the first and second flight extensions overlap when viewed along the auger longitudinal axis.
13. The poultry chiller of claim 1 wherein an angle of engagement of at least 30 degrees is defined between a leading edge of the second flight extension and an engagement edge of the hanger.
14. The poultry chiller of claim 1 wherein, as the auger rotates in the tank, the hanger passes through a gap defined by the first and second flights, and wherein an axial dimension of the gap has a greater length at the first and second auger shafts than at outer edges of the first and second flights.
15. The poultry chiller of claim 14 wherein a circumferential dimension of the gap has a greater length at the first and second auger shafts than at the outer edges of the first and second flights.
16. A kit for a poultry chiller comprising an elongated tank and an auger rotatably held lengthwise in the tank and including a first auger section and a second auger section, the kit comprising: a first flight extension that is configured to connect to a first helical portion of a first auger flight that is helically disposed on a first auger shaft of the first auger section; and a coupling shaft assembly comprising a first coupling flange configured to couple to a first end plate of the first auger shaft and a second coupling flange configured to couple to an adjacent second end plate of a second auger shaft of the second auger section; wherein the first and second coupling flanges are configured to allow adjustment of a rotational alignment between the first and second auger sections.
17. The kit of claim 16 wherein: the first coupling flange comprises a plurality of elongated slots defined therein and arranged in a circular pattern, the plurality of elongated slots configured to be aligned with a plurality of receiving holes defined in the first end plate of the first auger shaft; and the second coupling flange comprises a plurality of elongated slots defined therein and arranged in a circular pattern, the plurality of slots configured to be aligned with a plurality of receiving holes defined in the second end plate of the second auger shaft.
18. The kit of claim 17 wherein the plurality of elongated slots of the first coupling flange and the plurality of elongated slots of the second coupling flange are circumferentially offset from one another.
19. The kit of claim 16 wherein, when the first flight extension is connected to the first helical portion of the first auger flight, the first flight extension overhangs the first end plate of the first auger shaft.
20. The kit of claim 16 further comprising a second flight extension that is configured to connect to a second helical portion of a second auger flight that is helically disposed on the second auger shaft of the second auger section.
21. The kit of claim 16 further comprising a hanger bearing assembly comprising a bearing assembly configured to support the coupling shaft assembly and a hanger configured to extend between the bearing assembly and a support member coupled to an upper portion of the tank.
22. A poultry chiller comprising: an elongated tank; an auger rotatably held lengthwise in the tank and defining a longitudinal axis, the auger comprising: a first auger section comprising a first auger shaft and a first auger flight that extends radially away from the first auger shaft, the first auger flight comprising a first helical portion that is helically disposed on the first auger shaft and a first flight extension that extends away from the first helical portion; and a second auger section comprising a second auger shaft and a second auger flight that extends radially away from the second auger shaft, the second auger flight comprising a second helical portion that is helically disposed on the second auger shaft and a second flight extension that extends away from the second helical portion; a coupling shaft coupling a first coupling end of the first auger shaft and an adjacent second coupling end of the second auger shaft; and a hanger bearing assembly comprising a bearing assembly supporting the coupling shaft, a support member coupled to an upper portion of the tank, and a hanger extending between the bearing assembly and the support member; wherein a pitch or axial length between the first and second auger flights across the hanger bearing assembly is greater than a pitch of each of the first and second helical portions of the first and second auger flights.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
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DETAILED DESCRIPTION
(35) The present invention now will be described more fully hereinafter with reference to the accompanying drawings, in which illustrative embodiments of the invention are shown. In the drawings, the relative sizes of regions or features may be exaggerated for clarity. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.
(36) It will be understood that when an element is referred to as being “coupled” or “connected” to another element, it can be directly coupled or connected to the other element or intervening elements may also be present. In contrast, when an element is referred to as being “directly coupled” or “directly connected” to another element, there are no intervening elements present. Like numbers refer to like elements throughout. As used herein the term “and/or” includes any and all combinations of one or more of the associated listed items.
(37) In addition, spatially relative terms, such as “under,” “below,” “lower,” “over,” “upper” and the like, may be used herein for ease of description to describe one element or feature's relationship to another element(s) or feature(s) as illustrated in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is inverted, elements described as “under” or “beneath” other elements or features would then be oriented “over” the other elements or features. Thus, the exemplary term “under” can encompass both an orientation of over and under. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.
(38) Well-known functions or constructions may not be described in detail for brevity and/or clarity.
(39) The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the singular forms “a”, “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises,” “comprising,” “includes” and/or “including,” when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.
(40) It is noted that any one or more aspects or features described with respect to one embodiment may be incorporated in a different embodiment although not specifically described relative thereto. That is, all embodiments and/or features of any embodiment can be combined in any way and/or combination. Applicant reserves the right to change any originally filed claim or file any new claim accordingly, including the right to be able to amend any originally filed claim to depend from and/or incorporate any feature of any other claim although not originally claimed in that manner. These and other objects and/or aspects of the present invention are explained in detail in the specification set forth below.
(41) Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.
(42) As used herein, the term “monolithic” means an object that is a single, unitary piece formed or composed of a material without joints or seams.
(43) As used herein, the term “angle of engagement” means the angle formed between the leading edge of a downstream auger flight and the engagement edge (or first edge encountered) of the hanger. When the edges are non-linear, the angle is measured between the tangents to the curves at the point the edges intersect as viewed from the end of the auger.
(44) As used herein, the term “auger section” means a segment of an Archimedes screw including a central shaft and one or more revolutions of flight and configured to be supported at either end in a manner that permits rotation about the center of the shaft.
(45) As used herein, the term “flight” means the blade of the auger extending from the central shaft outward toward the tank wall in an approximately helical form. The flight engages the product and pushes the product along the length of the chiller as the auger turns. The flight may be pierced or discontinuous to facilitate water flow through the chiller and may have breaks or buttresses that deviate from pure helical form to provide structural stiffness.
(46) As used herein, the term flight “pitch” means the axial distance advanced as the helical flight makes one complete revolution of the axis. As described in more detail herein, the pitch may be locally altered.
(47) As used herein, the term “hanger” means a structural member that supports a bearing in which the auger assembly (one or more auger sections joined by coupling shafts) rotates. The hanger usually suspends the bearing from a structural beam situated across the top of the chiller tank. It should provide accurate and rigid positioning in the vertical and transverse directions, but need not be particularly rigid in the axial direction.
(48) As used herein, the term “leading edge” means the radial edge of an auger flight at the upstream end of an auger section.
(49) As used herein, the term “outer edge” means the edge of an auger flight farthest from the axis of rotation and closest to the tank wall.
(50) As used herein, the term “trailing edge” means the radial edge of an auger flight at the downstream end of an auger section.
(51) As used herein, the term “engagement edge” means the edge of a hanger which first passes by the leading edge of an auger as the auger rotates.
(52) As used herein, the term “engagement angle” means the angle between a tangent to the engagement edge of a hanger and a tangent to an adjacent leading edge of a flight or flight extension measured at the point at which the two edges intersect when viewed along the axis of auger rotation.
(53) As used herein, the term “flight extension” means a feature similar in structure to a flight and extending as a continuation of a flight but extending in a direction or configuration that may deviate from a helical form. A flight extension may extend approximately circumferentially from a flight.
(54) As used herein, the term “overhang” or “overhung” means that some portion of a feature such as an auger flight extends in an axial direction past the end of an auger shaft.
(55) In some embodiments, the term “substantially” when used in connection with a claimed angular relationship includes angles that are ±5° of the claimed angular relationship. In some other embodiments, the term “substantially” when used in connection with a claimed angular relationship includes angles that are ±3° of the claimed angular relationship. For example, a plane that is substantially perpendicular to an axis may form an angle with the axis that is between 85 and 95° or between 87 and 93° in various embodiments.
(56) Streamwise directions including “upstream” and “downstream” refer to the relative position of components with respect to the nominal direction in which the product progresses as it is processed in the chiller.
(57) An auger chiller 100 according to some embodiments is illustrated in
(58) The auger 120 extends from a product inlet end 114 of the tank 112 to a product outlet end 116 of the tank 112. The auger 120 includes an auger shaft 122. As understood by those skilled in the art, the auger 120 is rotatable in the tank 112 about a longitudinal or rotational axis A1 defined by the auger shaft 122 (e.g., by a motor that is operatively coupled to the auger shaft 122). The auger 120 may or may not be coaxial with the tank 112.
(59) The auger 120 includes a first or upstream auger section 124 and a second or downstream auger section 126.
(60) The first auger section 124 includes a first auger shaft 128 and a flight 130 helically disposed on the shaft 128. Similarly, the second auger section 126 includes a second auger shaft 132 and a flight 134 helically disposed on the shaft 132. The auger shaft 122 includes the first and second auger shafts 128, 132.
(61) Referring to
(62) Referring to
(63) Referring to
(64) Referring to
(65) The hanger bearing 140 includes a hanger 162 that is coupled to the bearing housing 156. Referring to
(66) In some embodiments, the hanger 162 when viewed in cross section (
(67) In various embodiments, the hanger 162 may have an average hanger width perpendicular to the auger longitudinal axis A1 that is at least six times greater, at least eight times greater or about 12 times greater than the hanger axial length parallel to the auger longitudinal axis A1.
(68) In some embodiments, the hanger 162 when viewed from an end of the tank may have a rectangular profile as illustrated in
(69) As illustrated in
(70) In some embodiments, and as illustrated in
(71) The bearing assembly 142′ may have an axial length L2 that is less than 6 inches and, in some embodiments, is less than 3 inches.
(72) Referring to
(73) The first and second flight extensions 170, 174 extend in a direction or plane perpendicular or substantially perpendicular to the longitudinal axis A1 of the auger shaft 122. The first and second flight extensions 170, 174 are on opposite sides of the hanger 162 and are parallel to the hanger 162. This configuration provides parallel faces (i.e., the flight extensions 170, 174) between which the hanger 162 passes as the auger rotates.
(74) Referring to
(75) As noted above in reference to
(76) Embodiments of the invention close or reduce this gap by extending the trailing edge 180 of the upstream flight 130 not in a helical direction but rather in a plane that is perpendicular to the longitudinal or rotational axis A1 of the auger. In addition, the leading edge 184 of the downstream flight 134 extends not in a helical direction but rather in a plane that is also perpendicular to the longitudinal or rotational axis A1 of the auger.
(77) Referring to
(78) As noted above in reference to
(79) Embodiments of the invention increase or open the angle of engagement between the hanger and the leading edge of the flight. As illustrated in
(80) When the angle of engagement is relatively large, product caught between the leading edge 184 of the flight 134 and the hanger 162 will be pushed toward the outer edge of the flight rather than being crushed between the edges of the flight and the hanger (see
(81) In other embodiments, the leading edge 184 may be straight or approximately straight while still forming a relatively open angle with the engagement edge 190. As illustrated in
(82) Referring to
(83) The first flight extension 170 may be at least partially supported by a first support plate 194 that is coupled to the first auger shaft 128 at or adjacent the first auger shaft coupling end 144. Similarly, the second flight extension 174 may be at least partially supported by a second support plate 196 that is coupled to the second auger shaft 132 at or adjacent the second auger shaft coupling end 146. The first and second support plates 194, 196 are configured to rotate with the first and second auger shafts 128, 132, respectively.
(84) The first and second support plates 194, 196 may be arc-shaped. As best seen in
(85) Referring again to
(86) It will be appreciated that the first and second flights 130, 134 need not overhang the first and second auger shafts 128, 132. For example, a “narrow” bearing assembly such as the one described in reference to
(87) Referring again to
(88)
(89) Referring to
(90) The second flight extension 174 is identical or symmetrical or substantially identical or symmetrical to the first flight extension 170. The first segment 202 of the second flight extension 174 extends from the second helical portion 176 of the second auger flight 134. The third segment 208 extends from the second auger shaft 132 and partially overhangs the second auger shaft 132. According to some other embodiments, the first and second flight extensions 170, 174 are not identical or symmetrical (e.g., one may have different geometry than the other).
(91) The first flight extension 170 at least partially overhangs the first auger shaft 128. Likewise, the second flight extension 174 at least partially overhangs the second auger shaft 132.
(92) The edge of the flight extensions 170, 174 closest to the hanger 162 may be structurally reinforced with an elongated reinforcement member such as a bar, pipe or rod 212. An elongated reinforcement member such as a bar, pipe or rod 212 may also be positioned between the first segments 202 and the helical portions 172, 176. Additionally or alternatively, the flight extensions 170, 174 may be supported with gusset connected to the auger shafts 128, 132. The gussets may connect to the third segments 208 of the flight extensions 170, 174. The elongated members and/or the gussets help ensure that the flights 130, 134 are reinforced to increase the rigidity of the flight as it pushes product through the chiller.
(93) Referring to
(94) Referring to
(95) The present inventor has determined that the circumferential gap G1 has more latitude for adjustment to meet the needs of particular circumstances (e.g., the size of product in the chiller). The circumferential gap G1 can range from overlapping by up to several inches to a separation of up to 30 degrees (based on the angle β between the trailing edge 180 of the upstream auger flight 130 and the leading edge 184 of the downstream auger flight 134). The circumferential gap G1 is preferably small enough that units of product will not pass through easily. The present inventor has determined that a circumferential gap G1 equal or less to the axial gap G has proven acceptable. According to some embodiments, and as illustrated in
(96) The present inventor has discovered that it is important that the hanger 162 not obstruct the forward path of product on the “pulling side” of the chiller (i.e., the side on which the auger rises as it rotates). This corresponds to the side of the tank 12 to the right of the auger shaft 122 in
(97) In addition, the design of the hanger assembly should provide space between the top (or outer) edge of the auger flight and the bottom side of the support member at the leading (or engagement) edge of the hanger. The space or opening should be large enough to allow clearance above the flight for units of product that are pushed to the edge of the flight when the gap in the flight passes by the hanger. Once the product is pushed into the space beyond the flight, it may fall to one side or the other of the flight.
(98) Along these lines, and referring to
(99) As product progresses through the chiller, it is desirable to reduce the density of product in the chilling liquid in the vicinity of the hanger bearing. The present inventor discovered that this may be accomplished by increasing the pitch of the auger as it crosses the hanger bearing. Again, pitch is the axial distance between one point on the auger blade or flight to another point exactly one revolution along the flight. The determination of one revolution will ignore any break or discontinuity between one auger section and the next to arrive at the same circumferential position (clock position).
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(102) In instances where a conventional auger chiller is being modified to employ the advantages of the current invention, the coupling shaft 152 may be configured to allow adjustment of the rotational alignment between a first auger section 124 (or first auger shaft 128) and a second auger section 126 (or second auger shaft 132). One such embodiment is shown in
(103) In other embodiments, one or both of the coupling shaft flanges 151, 153 may have a plurality of round holes instead of slots. For example, a flange could have more (e.g., twice as many) holes spaced around the bolting circle as there are bolt holes 234 in the auger end plates 148, 150. By choosing which holes are used to couple the coupling shaft to an auger end plate, the rotational alignment of the first and second auger sections could be altered. Those skilled in the art will understand that other methods may be used to rotationally couple the auger sections while allowing some flexibility for rotational alignment.
(104) Some embodiments of the invention are directed to a kit for modifying or retrofitting a conventional auger chiller. The kit may include a first flight extension 170 for connecting (e.g., welding) to a helical flight of a first auger section and/or a second flight extension 174 for connecting (e.g., welding) to a helical flight of a second auger section. The kit may include a hanger bearing assembly 142 as described herein. The kit may include a hanger 162 as described herein. The kit may include the coupling shaft assembly 230 described above.
(105) Several of the embodiments described herein include a first flight extension 170 and a second flight extension 174. In some embodiments, only one flight extension 170 or 174 is required to meet the intent of the current invention. For example, as illustrated in
(106) Several features related to the flight extensions 170, 174 have been described in the present application. For example, the flight extensions 170, 174 may extend from helical portions 172, 176 of flights 130, 134. A respective flight extension may overhang the end of the shaft. Also, the trailing edge 180 of the first flight extension 170 may be separated from the leading edge 184 of the second flight extension 174 by a gap that has an axial dimension G and a circumferential dimension G1. A preferred pitch P′ between the first auger flight 130 and the second auger flight 134 has been described. It will be understood that not all of these features are required in every embodiment. Any configuration of the flight extensions which satisfies essential requirements as described herein falls within the intent and scope of the present invention. For example, the flight extensions need not conform to a helical disposition about the auger shaft, nor must they be disposed perpendicular to the axis A1 provided other relevant requirements as described herein are met.
(107)
(108) Referring to
(109) Similarly, the flight extension 174 extends radially between an outer edge 222h of the helical portion 176 of the second auger flight 134 and a second point 244 at an inner portion 246 of the helical portion 176. The second point 244 is spaced apart from the second auger shaft 232 (
(110) The present inventor has determined that, for larger product (e.g., turkeys), it may be desirable to have a larger circumferential gap to allow units of product to pass therethrough. As best seen in
(111) The flight extension 170 may be coupled (e.g., welded) to the helical portion 172. There may be a terminal rod 248 on a radial edge of the helical portion 172, and the flight extension 170 may be coupled to the terminal rod 248. Alternatively, the flight extension 170 and at least a portion of the helical portion 172 may be monolithic. One or more terminal rods 250 may optionally be on an open or otherwise unattached edge of the flight extension 170. The flight extension 170 and the helical portion 172 (or the inner portion 242 thereof) may define the trailing edge of the first flight 130.
(112) Similarly, the flight extension 174 may be coupled (e.g., welded) to the helical portion 176. There may be a terminal rod 252 on a radial edge of the helical portion 176, and the flight extension 174 may be coupled to the terminal rod 252. Alternatively, the flight extension 174 and at least a portion of the helical portion 176 may be monolithic. One or more terminal rods 254 may optionally be on an open or otherwise unattached edge of the flight extension 174. The flight extension 174 and the helical portion 176 (or the inner portion 246 thereof) may define the leading edge of the second flight 134.
(113) The circumferential gap G2 may widen from the first and second auger shafts 128, 132 (
(114) The first auger flight 130 may include the first helical portion 172 that is helically disposed on the first auger shaft 128 and the first flight extension 170 that extends approximately circumferentially away from the first helical portion 172. Similarly, the second auger flight 134 may include the second helical portion 176 that is helically disposed on the second auger shaft 132 and the second flight extension 174 that extends approximately circumferentially away from the second helical portion 176. As used herein, the first (or second) flight extension that “extends approximately circumferentially away” from the first (or second) helical portion means that the flight extension extends between a plane normal to the shaft axis and a continuation of the helical path of the flight.
(115) Although chillers having first and second auger sections have been described in detail, it will be appreciated that chillers having more than two auger section are within the scope of the invention. For example, a chiller may have three auger sections. A central auger section could be coupled to two outer auger sections (e.g., using two coupling shafts and two hanger bearing assemblies as described herein), and the two outer auger sections could be coupled to the tank at or adjacent opposite end walls.
(116) The foregoing is illustrative of the present invention and is not to be construed as limiting thereof. Although a few exemplary embodiments of this invention have been described, those skilled in the art will readily appreciate that many modifications are possible in the exemplary embodiments without materially departing from the teachings and advantages of this invention. Accordingly, all such modifications are intended to be included within the scope of this invention as defined in the claims. The invention is defined by the following claims, with equivalents of the claims to be included therein.