Patent Publication Number: US-3879150-A

Title: Pumping supply system for delivering at ambient temperature highly viscous material

Description:
United States Patent 11 1 Brown et al.  
 [ 51 Apr. 22, 1975 PUMPING SUPPLY SYSTEM FOR DELIVERING AT AMBIENT TEMPERATURE HIGHLY VISCOUS MATERIAL [75] Inventors: Joseph L. Brown, Dallas; Don L. Terry, Duncanville, both of Tex.  
 [73] Assignee: Kentucky Fried Chicken Corporation, Louisville, Ky.  
  22 Filed: Nov. 6, 1973 21 Appl. No; 413,237  
 [52] US. Cl. 415/72; 259/6; 222/238 [51] Int. Cl. F04d 3/02; BOlf 7/08; BOlf 15/02 [58] Field of Search 415/72, 73, 74, 11; 259/6,  
 [56] References Cited UNITED STATES PATENTS 1,209,790 12/1916 Woodcock 222/238 1,668,324 5/1928 Kreisingcr 222/238 2,509,379 5/1950 Vasel 259/6 2,991,870 7/1961 Griffith 259/6 3,114,933 12/1963 Ambrette 259/6 3,704,076 11/1972 Vasilicvich 415/73 OTHER PUBLICATIONS St. Regis CP Food Equipment and Refrigeration Division Bulletin A-l-SOO.&#34;  
 Primary Examiner-C. J. Husar Assistant Examiner-Louis .l. Casaregola Attorney, Agent, or F irmWatson Leavenworth Kelton &amp; Taggart [57] ABSTRACT Known pumping supply system consists of supply vat having in its bottom section twin lateral delivery screws extending to a discharge outlet in an end wall and which are rotated in opposite directions. The discharge outlet is flow connected to the intake of a delivery pump. The present improvement adds thereto a pair of oppositely rotated, laterally extending and transversely spaced, flow-directing feeders mounted in the vat relatively closely above the delivery screws. Each feeder has a driven shaft on which is mounted along diametrically opposite sides thereof a pair of sets of a plurality of substantially radially extending and rather closely spaced paddles. These sets of paddles of one feeder shaft are rotated by its shaft out of radial angular phase with those of the other feeder shaft. These rotating feeders cooperatively force the viscous material down into the lateral trough-shaped receiving throat between the delivery screws. This improvement also includes a delivery and return conduit which is flow connected between the discharge opening of the delivery pump and an upper portion of the vat. Between the delivery pump and a terminal portion of this return conduit there is flow connected to the latter one or more supply branch lines to supply the pumped material to one or more use receiving stations. Each branch line may have connected therein a flow rate controlling pump.  
 2 Claims, 4 Drawing Figures PATENTED 3,879,150  
 SHEET 1 BF 3 5 a; 5 E D. f D D. 5 g m E MAIN OUTPUT PUMP ATENTEDAPRZZIBYS SHIT 2 UP 3 Q $8 JR W &#34;M a WIFW, 1 MWM W mm w i I w 9 w. 8 R 3 l i :1  
 PUMPING SUPPLY SYSTEM FOR DELIVERING AT AMBIENT TEMPERATURE HIGHLY VISCOUS MATERIAL BACKGROUND AND SUMMARY The present invention relates to pumping systems featured by oppositely rotated twin lateral delivery screws located in the bottom sections of supply vats thereof in which is placed masses of highly viscous paste material for discharge thereof from the vat by the screws through an end wall of the vat to a main delivery pump.  
  Such an equipped supply vat is proposed in Bulletin A-l-500 of the CP Food Equipment and Refrigeration Divsion of the St. Regis Company. 1243 W. Washington Boulevard, Chicago, Illinois 60607. However, that equipment called the CP Pumping System&#34; is designed to comparatively large scale so as to serve its intended purpose for relatively high capacity rates of delivery flow. When such equipment is attempted to be used for relatively low capacity operation in the baking industry to deliver uniformly relatively exact amounts of highly viscous butter and stiff margarine or shortening at ambient temperatures, to avoid the deterioration thereof as to taste and physical characteristics by application of liquefying heat, undesirable bridging occurs at the rotating delivery screws and pockets of air become entrapped in the delivered paste material which interferes deleteriously with the desired uniform rates of flow at the receiving dough sheeters, premixers, and dough developers.  
  These and other undesirable characteristics are efficiently overcome or eliminated by the added features of the present invention.  
  An object of the present invention is to improve such a pumping supply system so that the supply output is at the desired uniform low capacity rate of flow and the delivered flow or flows is or are substantially free of entrapped air pockets.  
  Another object is to eliminate substantially the ten dency at low operational speeds for the paste material in the vat to bridge threads of the delivery screws which tends to cause air entrapment, and which assures uniform output flow.  
  A further object is to provide a delivery conduit which defines a flow path between the main delivery pump and back to the vat which has a greater flow capacity than the maximum delivery rate capacity of use receiving means at one or more locations, with each of the latter flow connected to this delivery conduit by a branch supply line of the delivery conduit that assures constant positive flow at uniform pressure at the use receiving means with the delivered flow or flows being free of entrapped air pockets.  
  Briefly, the added equipment of the present invention includes (1) a pair of rotatably driven feeders located in the vat just above the twin rotated discharge screws and (2) the return line in the form ofa delivery conduit extending between the main delivery pump and the vat with branch line or lines for one or more use receiving means being flow connected to this delivery conduit.  
  Each feeder includes a rotatably driven lateral shaft preferably having its ends supported by bearings carried by the opposed end walls of the vat. Each feeder shaft carries along its length between the vat end walls a plurality of substantially radially extending paddles which preferably are provided in two diametrically opposite sets thereof. These paddles preferably are rather narrow in width and in each set are spaced along the shaft at relatively small distances, e.g., about the width of each paddle. The two rotary feeder shafts are driven in opposite directions with that located immediately above one of the screws being rotated in the same direction as the latter. This causes the paddles carried by one of the feeder shafts to swing forward toward the other feeder shaft and downward through the transverse space that intervenes them, so that the sets of paddles on both shafts cooperatively force the paste materials down into the trough-shaped receiving throat between the oppositely driven discharge screws, so as to avoid undesirable bridging of the screw blade turns.  
  The delivery conduit which extends from the discharge opening of the delivery pump to the branch delivery line or lines, that extends or extend to the one or more use receiving means, has a terminal section beyond this branch line or these branch lines which extends back to the chamber of the vat above the feeders as a return flow line. The flow capacity of the delivery pump and this delivery conduit is greater than the maximum demand of the use receiving means, so that, in operation of this pumping supply system, there is always return flow back to the vat chamber.  
  Other objects of the invention will in part be obvious and will in part appear from reference to the following detailed description taken in connection with the accompanying drawings, wherein like numerals identify similar parts throughout. and in which:  
  FIG. 1 is an elevational perspective of an embodiment of the pumping supply system of the present invention as designed for use in the baking industry;  
  FIG. 2 is a longitudinal sectional view taken substantially on line 22 of FIG. I, with parts broken away and others in side elevation, of the supply vat and delivery conduit extending therefrom toward the delivery P p? FIG. 3 is an elevational view taken substantially on line 33 of FIG. 1, with parts broken away, of the end of the vat opposite the outlet end thereof; and  
  FIG. 4 is an enlarged transverse sectional view, with parts broken away, taken on line 4-4 of FIG. I, showing the bottom of the section of the supply vat and the equipment mounted therein.  
  As will be seen from the drawings the pumping supply system of the present invention includes an open top supply vat 10 having a supply chamber 11 defined by a pair of opposed and longitudinally spaced transverse end walls 12 and 13, a pair of opposed and transversely spaced sidewalls 14 and 15, and a longitudinally extending bottom structure 16. As will be seen from FIG. 1, and as is shown in FIG. 4, the supply chamber 11 defined by the supply vat 10 has a bottom section 17. The walls of the tank 10 are made of corrosion resistant sheet metal which is compatible with and does not deleteriously affect the paste material, e.g., highly viscous butter or stiff margarine and shortening, and accordingly may be made of sheeted stainless steel or other sheet metal which may be painted or coated with an approved plastic.  
  As will be seen from FIGS. 2 and 4 the exit end wall 12 is provided with a laterally directed outlet which may be in the form of a pair of discharge openings 18 and 118. The composite laterally directed outlet, in the form of the pair of outlet openings 18 and 118, feed into a manifold sleeve 19 which is flow connected to the mouth of a truncated tapered supply tube 21, as will be understood from FIGS. 1 and 2. The discharge end 22 of the supply tube 21 is connected to the intake 122 of a positive displacement pump 23, as will be understood from FIGS. 1 and 2, and this pump constitutes delivery pumping means having its intake flow connected to the vat outlet cooperatively provided by the outlet openings 18 and 118.  
  As will be understood from FIGS. 2 and 4 a pair of delivery screws 24 and are rotatably mounted in the vat chamber bottom section 17 in lateral orientation and closely spaced general parallelism in any suitable manner. The delivery screws 24 and 25 respectively include shafts 124 and 125 about each of which are respectively carried spiraled thrust blades 26 and 27. As will be understood from FIGS. 2 and 4 the spiral blade 26 is right handed and the spiral thrust blade 27 is left handed, so that as the screw shafts 124 and 125 are rotated in opposite direction they both cooperatively advance paste material in the vat chamber bottom section toward the discharge vat end wall 12. The shaft of the delivery screw 24 has its back end suitably journaled through the vat end wall 13, to carry, fixed thereon, exterior of the vat chamber, a driving spur gear 28, and the forward end of this screw extends coaxially through the discharge opening 18 into the tubular manifold 19 for suitable journaling therein (not shown).  
  The journal mounting of the delivery screw 25 is similar to that of delivery screw 24, with coaxial extension of its forward end through the discharge opening 118. As is indicated in FIG. 3 the extending back end of the delivery screw shaft 125 carries exterior of the vat chamber and the back end wall 13 suitable driving means, such as in the form ofa pulley 29 fixed thereon about which is lapped a suitable driving belt 30, which may be a chain belt, that in turn is lapped about a drive pulley 31 fixed on the output shaft 32 of a suitable drive motor 33. The delivery screw shaft 125 also carries, fixed thereon, a spur gear 34 which is meshed with the spur gear 28, so that as the motor 33 rotates the delivery screw shaft 125 in clockwise direction, as viewed in FIG. 3, spur gear 28 which is meshed with gear 29 rotates the delivery screw shaft 124 in counterclockwise direction.  
  As will be best understood from FIG. 4 the oppositely rotated driven delivery screws 24 and 25 define therebetween a lateral trough-shaped receiving throat 35, into which the paste material loaded into the vat chamber 11 will progressively feed, particularly when suitably urged into this throat, for extrusion of the paste material out through the discharge openings 18 and 118 for progressive delivery through the manifold 19 and the sleeve 21 into the intake 122 of the delivery pump 23 at a substantially constant pressure. Since for the particular service for which this embodiment of the pumping supply system is designed, e.g., for the baking industry to supply the stiff butter, margarine or shortening, to a plurality of use receiving means, such as a dough sheeter, a premixer, and a dough developer, the constant pressure of the stiff paste material is to be relatively low, e.g., approximately 2 pounds. Thus, the mere weight of the mass of paste material which is loaded into the vat chamber 11, preferably by hand, is not sufficient to assure that it will enter between the turns of the delivery screw blades 26 and 27 without bridging, so as to form air pockets therein unless suitable feeding means is provided in the tank chamber bottom section immediately above these delivery screws to perform this function.  
  As will be understood from FIGS. 2 and 4 such necessary feeding means is in the form of a pair of oppositely rotated, laterally extending and transversely spaced flow-directing feeders 36 and 136 that are mounted in the vat chamber bottom section 17 relatively closely above these delivery screws 24 and 25 with these including respectively lateral shafts 37 and 137 of similar construction and mounted in similar manner between the vat end walls 12 and 13. For example, feeder shaft 37 is rotatably supported by a suitable journal 38 on back end wall 13 with the back end of this shaft projecting through this back end wall to carry thereon and fixed thereto, exterior of the vat chamber 11, driving pulley 39 and drive spur gear 40. A similar journal 138 rotatably supports the front end of this feeder shaft 37 upon the discharge end wall 12. Such journals may, for example, be Teflon bearings.  
  Each feeder shaft, such as 37, carries along its length and fixed thereto a plurality of substantially radially extending paddles 41 and 141. Preferably, these paddles are arranged in two diametrically opposite sets, which may be about 2%inches long and about three-quarters of an inch wide. Thus in each of the two diametrically opposite sets these paddles 41 and 141 are of relatively narrow width and are spaced longitudinally along the shaft at relatively short distances apart, such as about three-quarters of an inch. It is preferred that these paddles 41 and 141 be substantially flat and extend substantially radially of the axis of the shaft 37 or 137 on which they are mounted, with the paddles in one set, Le, 41, being staggered longitudinally relative to those in the opposite set, i.e., 141.  
  These feeders 36 and 136 are arranged and so driven as to be rotated in opposite directions, i.e, those mounted on shaft 37 as viewed in FIG. 4 to be swung counterclockwise and those mounted on shaft 137 to be swung clockwise. Accordingly, the feeder shafts 37 and 137 are rotated in opposite certain directions which cause the paddles carried by each to swing forward toward the other feeder shaft and downward through the transverse space intervening these feeders cooperatively to cause them to force the paste material down into the trough-shaped receiving throat 35 between the discharge screws 24 and 25. It is also preferred that the paddles 41 and 141 which are embodied in feeder 36 and those which are embodied in feeder 136 are arranged out of radial angular phase with respect to each other, e.g., at right angles or This out of phase angular relationship of the paddles of one feeder with respect to those of the other feeder assures that there will be no undesirable interference with the downward forcing action of the paddles of one with respect to those of the other, and also elimination of any possible physical interference of the paddles of one feeder with respect to those of the other feeder. It will also be noted that these respective feeders are rotated in the same directions as are the discharge screws located immediately therebelow, i.e., discharge screw 24 and feeder 36 are rotated in counterclockwise direction, and discharge screw 25 and feeder 136 are rotated in clockwise direction.  
  As will be understood from FIGS. 2 and 3 the projecting back end of discharge screw shaft 124 also carries, fixed thereto, beyond spur gear 28 a pulley 42. An endless belt 43 is lapped about screw pulley 42 and l s feeder pulley 39 for drive of the latter from the former. Feeder shaft 137 has its projecting back end carrying, fixed thereto, a similar spur gear 140 which is meshed with spur gear 40. Thus the motor 33 drives both of the feeders 36 and 136 and the discharge screws 24 and 25 simultaneously in the desired indicated directions.  
  The delivery pump 23 has its discharge outlet at 44 connected to delivery conduit means or. a pipe 45 which leads to use receiving means. For this purpose delivery pipe&#39;4l may carry a T-fitting 46 which has one arm flow connected to the pipe 45 and the other arm connected to a suitable branch line 47 which is to lead to one use receiving means or equipment, such as a cer- I tain one of a dough sheeter, a premixer, and a dough developer. A vertical pipe 145 is mounted to the leg of the T-fitting 46 and has branch lines 48 and 49 flow connected thereto. The branch lines 48 and 49 respectively feed to additional use receiving means such as the other two of the three equipments mentioned above. Thus these branch lines 47, 48, and 49, and their respective extensions 147, 148, and 149 provide supply conduits for three different stations, e.g., No. 1, No. 2, and No. 3. Preferably, each of these three supply branch lines has inserted therein a separate flow rate controlling pump. Each such pump (50 or 150 or 250) is driven by a speed controlled motor and the speed thereof determines the rate of delivery output of the feeder line in which it is inserted.  
  Flow through the upright run 145 of the delivery conduit is connected by a T-fitting 51 (which may be an elbow) to a terminal section pipe 52 which leads back to the vat chamber 11 for return to this vat chamber of the excess of paste material above the composite demand of the three station branch lines 47, 48, and 49 and their flow rate controlling pumps 50, 150, and 250. In other words, the delivery conduit means defines a direct return flow path from the discharge opening of the delivery pump 23 back to the vat chamber for discharge into the latter preferably at a point above the vat chamber bottom section. lf it is desired to provide a removable cover for the vat the terminal section 52 of the delivery conduit may extend through a suitable opening in one of the sidewalls of the vat near the top of the latter, then to extend down to the desired point of discharge.  
 It will be noted from FIG. 1 that the upright run or section 145 of the delivery conduit preferably also includes, for convenience, another T-fitting 53, so that the leg 54 thereof may serve to communicate the interior of such conduit with a suitable pressure meter 55. The T-fitting 51 may also house, for convenience, a flow controlling valve of conventional or suitable construction, with an externally accessible hand knob 56 being provided thereon to adjust the size of the flow passage therethrough. Such adjustable flow control valve may thus be adjusted so that the pressure in the return line may be maintained at a value which is best suited to assurance that the returned excess of the buttery composition or paste material being delivered by the pumping system is kept substantially free of air voids. All of the runs or sections and fittings of such delivery conduit and return line desirably may be formed of suitable material, such as stainless steel, that is compatible with the composition being pumped therethrough, so as not to contaminate the latter, particularly when it is a foodstuff.  
  As a result of this delivery conduit means and its branch lines there is feed of the paste material to the three different&#39;stations at constant pressure. The three feed pumps 50, 150, and 250 in the three delivery or supply branch lines which are operating at constant pressure, provide a uniform and exact or precise rate of flow of the paste material to each station. Since the paste material is not preheated to increase the fluidity thereof for facilitating the operation of this supply and delivery system deleterious effect of heat on flavor is avoided. The insertion of the unheated stiff butter, margarine, or shortening between layers of the dough by such a continuous process assures the production of a more uniform product and gives a prebuttered effect while eliminating any need for heating butter when the roll is to be readied for eating. Also, by avoiding the heating of the buttering material the difficult cleaning process of the equipment is materially and desirably reduced. By virtue of the supply of the stiff butter material at the developer for distribution throughout the dough assures a more uniform and desirable taste, and the supply thereof at the premixer provides desired lubrication so that the otherwise stiff dough can be pumped while avoiding lumping. It is highly desirable in the baking industry to keep the dough at the lowest possible temperature so as to prevent melting of the buttering material and delivery by the present pumping supply system to the respective stations in the manner indicated prevents excessive heat buildup.  
  It will thus be seen that the objects set forth above, among those made apparent from the preceding description, are efficiently attained and, since certain changes may be made in the above construction without departing from the scope of the invention, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.  
  Having described our invention, what we claim as new and desire to secure by Letters Patent is the novel subjects matter defined in the following claims:  
  1. A pumping supply system for delivering at ambient temperature highly viscous and butter-like paste material at a relatively uniform rate of flow and substantially free of air voids comprising, in combination;  
 1. a supply vat defining a supply chamber having a lateral bottom section provided at one end with a laterally directed outlet;  
 2. delivery pumping means having its intake flow connected to the vat outlet;  
 3. a pair of oppositely rotated and laterally extending driven delivery screws in the bottom section of said vat chamber extending in closely spaced general parallelism to said vat outlet which define therebetween a lateral trough-shaped receiving throat;  
 4. a pair of oppositely rotated, laterally extending and transversely spaced, flow-directing feeders mounted in said vat chamber bottom section relatively closely above said delivery screws, each comprising a driven lateral shaft carrying along its length and fixed thereto a plurality of substantially radially extending paddles; and  
 5. means to drive said feeder shafts in opposite certain directions that cause said paddles on each of said feeder shafts to swing forward toward the other feeder shaft and downward through the transverse space intervening said feeders cooperatively to cause the latter to force the paste material down into the trough-shaped receiving throat between said screws;  
 6. said delivery pumping means having its discharge opening connected to delivery conduit means leading to use receiving means which demands less than the maximum delivery rate capacity of the delivery pumping means and said delivery conduit means, the latter having a terminal section defining a flow path back to said supply vat for return to the latter of the excess above the demand of the use receiving means; and  
 7. said use receiving means comprising a plurality of separate use receiving stations with a plurality of supply branch lines connected to said delivery conduit means between the delivery pumping means and the terminal return section with each branch line leading to one of said stations, each branch line including a separate flow rate controlling pump. 2. The pumping supply system as defined in claim 1 characterized by said delivery conduit means defining a direct return flow path from the discharge opening of said delivery pumping means back to the interior of said vat at a point of discharge above said vat chamber bottom section said plurality of supply branch lines for the separate use receiving stations being directly flow connected to said conduit means between the discharge opening of said delivery pumping means and the terminal return section of said conduit means.