US2657094A - Recirculation system - Google Patents

Description

INVENTORS WASHINGTON H.PHILLIP$ GEORGE E.GARD

OOOOOOOOO0000000000000000000000000000000000* 0000c00000000000000000000000000 ATTORNEY 3 w. H. PHILLIPS ET AL RECIRCULATION SYSTEM Filed Nov. 1'7, 1950 Patented Oct. 27, 1953 RECIRCULATION SYSTEM Washington H. Philli Lancaster, Pa., assi Company, Pennsylvania Lancaste ps and George E. Gard, gnors to Armstrong Cork r, Pa., a corporation of Application November 17, 1950, Serial No. 196,136

'7 Claims. 1

This invention relates to a system for the recirculation of fluent materials and is concerned more particularly with a system for the recirculation of heated and liquefied normally solid or semisolid binder materials used in the manufacture of cork compositions and the like.

In the manufacture of cork compositions, one of the most commonly employed binders is made by heating together a mixture of animal glue, glycerine, and water. In order to obtain a relatively uniform distribution of this binder over the light low density cork granules, a preblending system has been proposed which is disclosed and claimed in the copending application of Washington H. Phillips, Serial No. 196,135, filed November 17, 1950, and entitled Method and Apparatus for Making Cork Compositions and the Like. In Phillips preferred process the heated binder is distributed over two freely fiowing thin streams of cork granules by directing small streams of the binder in a downward direction, the paths of the streams of binder intersecting the paths of travel of the cork granules. There is thus systematically applied to a. substantial portion of the granules a measured quantity of binder material. The granules are then delivered to a mixing device where mechanical working is accomplished, and the binder is there uniformly distributed as thin films over all of the cork granules.

This system of applying the binder to the granules employs a distribution conduit which may be in the form of a tube having relatively closely spaced and small distribution orifices drilled therein. These openings tends to be reduced in size and eventually to be closed bycongealing of the binder around and within the openings.

An object of the present invention is to provide a continuous heating system for the distribution conduit to assure a continuous supply of fluent material through the distribution orifices, minimizing or eliminating the problem of reduction in size or closing of the orifices due to congealing of the fluent material at the orifices.

Most of the binders employed in cork composition manufacture are heat-sensitive and change materially in viscosity with changes in temperature. Where only small volumes of binder are applied, it is difiicult to deliver the binder to the cork particles at a temperature closely approaching that of the binder supply.

Another object of this invention is to provide an arrangement whereby a substantial volume of fluent material will be delivered to the discharge conduit, a small volume will be discharged 2 through the distribution orifices, and a substantial volume will be recirculated back to the bulk supply. This insures that the binder delivered through the orifices will be at a temperature about the same as that of the bulk supply.

Another problem which is present in the manufacture of cork compositions in accordance with the Phillips method is that of shut-downs which occur over lunch periods, at the end of the working day, week ends, and at other times when it is normally necessary to remove all the binder from the system in order to avoid congealing oi it within the distribution conduit and the associated supply and return system.

A further object of the invention is to provide an arrangement which will eliminate the necessity for cleaning out the system but will provide instead for the continuous delivery of the fluent material through the system, including the discharge orifices, thus maintaining the system in condition for instant operation.

With small distribution orifices there is a major roblem of maintaining the fluent material to be distributed free of foreign bodies which might clog the openings or impede the delivery of the material in a measured volume through the orifices.

An additional object of the invention is to provide a recirculation arrangement including a filter through which all of the fluent material must pass, including all recirculated. material.

Other objects of the invention will become apparent from consideration of a preferred embodiment of the invention which will be described presently.

According to this invention there is provided a system which is substantially closed to the atmosphere and includes a tank for the bulk supply of the fluent material and a pump which receives the material from the tank and delivers it under pressure to a distribution conduit. A filter is provided in the line from the tank to the pump. The distribution conduit is connected on one end to the discharge side of the pump, and the other or discharge end of the distribution tube is received within a discharge sleeve which connects to a return line to the bulk supply tank through an appropriate control valve. With this arrangement a large volume of fluent material as compared with the volume discharged may be fed through the system and continuous recirculation eifected. Also, the volume of material supplied through the discharge orifices may be controlled by adjustment of the valve in the return line.

The discharge sleeve which receives the discharge end of the distribution conduit is arranged so that the same may be moved relative to the distribution tube to be disposed over the distribution orifices in spaced relationship with respect thereto. Inthis manner, material may be delivered through the distribution orifices at all times including inoperative periods, the same beingdelivered into the discharge sleeve and recirculated throughthe return system to the bulk Supply tank. It is preferred to provide {or restriction of the free flow of the material from the discharge end of the distribution tube when the discharge sleeve isdisposed thereover so as to positively force a part of the heated -binder to be delivered through the distribution orifices therein and thus maintain them in proper cleared condition It is also desirable 130 provide for the discharge of a substantial volume of the material through the discharge end of the distribution tube in order to avoid compaction of any foreign particleswithinthedischarge orifices which might result if the entire capacity of the pump were to be disposed of through the .distribution orifices. Means for resisting flow from the discharge end ofthe distribution-conduit are provided for such purposes.

In order that the invention may be readily'understood, a preferred embodiment thereof will be described in conjunction-withthe attached draw- ;in which:

'Figure l is a diagrammatic view of a system embodying the present invention;

Figure 2 isa viewin elevation, to a-scale larger than Figure l, of a portion ofatypical discharge conduit showing the discharge orifices therein; and

FigureSis a-diagrammatio view-showing a portion of the system with the distribution tube in open or binder-applying position.

Referring first to Figure l,'t-here is disclosed a tank 2 which maybe the nature of 'a steamjacketed *heating kettle provided with suitable means 'for agitating the binder. 'This tank 2 is preferably provided with thermostatic control means for maintaining a predeterminedtemperature in the materialdisposed therewithin. For purposes of illustration, a system for the {distribution of a heat-liquefied glue, glycerine, and water binder for application-to,cork granules has been illustrated in thedrawings and will be described. Tank 2 is proyided with a discharge outlet 3 which leads to a filter 4 which is effective for removing foreign particles which may be present in the binder and also-,serves to break down any bubbles which may occurin the binder.

Apurnp 5 including an electric motor 6 receives the material from the tank 2 and delivers it through a flexib h se whi h' co n t d by a union .8 to a distribution conduit J. The distribution conduit 9jis shown inFigure '2 and may "be formed of a piece of copper pipe about one- 1half inch in insidediameter. 'It is provided with a plurality of small drilled openings 11]. As disclosed in the impending application of Washington 'HJPhilIipS, previously referred to, Where the conduit 9 is aboutqlS" long, there may be forty 3 op ni s in .th con u t T e i e .o op n heir si e may v e d ng u the y of h de be ng disch r e nd vother variable factors. For most binders used in the preparation of corkcqmpositions, ,a one ha'lf inch conduit with about ort e 2 .opehine 'm len th of about 48 will 'befoundsatisfactory.

As will be observed by reference to figure ,3, the discharge end ll of the distribution conduit 4 9 is open and is disposed within a discharge sleeve I2 which may have an internal diameter of about 1". This is the normal position of the distribution conduit and discharge sleeve when the binder is being distributed through the openings Ill. The distribution conduit 9 is sealed with respect to the discharge sleeve l2 by; a packing cap I3 which is threaded onto the end of the discharge sleeve I2 and clamps a body of pack- "ing material 14 into sealing relationship with the .outermallpf the distribution conduit 9.

On the other end of the discharge sleeve I2 there is-provideda -T connection l5, one leg of which ;is threaded onto the discharge sleeve 12 and the alignedileg l6 of which receives a conventional pipe plug [1. The third leg [8 receives-amipple :l-9 which has attached thereto a control valve 20. A flexible hose 2| connects from the valve 20 to adischarge pipe 22 which is received within a threaded bushing 23 provided in the tank 2.

normal operation of the device the discharge' sleeve 4'2 will be retracted to the position shown-in Figure 3,-and the pump 5 will be placed into operation, pumping the heated binder from the tank 2 through the filterd andintothe flexible hose *1 which delivers the binder to the :distribution conduit 9. Aportion of the volume of binder supplied by the pump 5 will be-delivered through the distribution orifices 10 of the conduit 9, and the remaining portion will be deilivered tram the discharge end H of the conduit 9 into-the discharge sleeve [2, through theT connection 15, and past the valve 2'0, thence through'the'flexi-blehose ill and the line 2-2,-back to the tank 2. For example, thevalve 20 maybe adjusted to provide -for the :delivery of about 6 pounds of binder per -minute through the discharge orifices, and the remaining volume delivered by the pump, which may be 30 pounds, -is discharged for recirculation. This represents about20% of the total Whichis delivered-through the orifices and recirculated. If it be desired to increase or decrease the quantity of binder delivered through the distribution orifices, the valve 20 may 'be adjusted to effect the desired change throughjncrease or decrease in the back pressure on the system. There-will-be continuously flowing into 'the conduit '9 and through the distribution orifices II) a volume of heated 'binder adequate tomaintain the entire'sy'stem at asuif ciently high temperature-to avoid any congealing of .the ,binderat the distribution orifices.

"Bysupplying a"large volume of binder to the conduit and continuously recirculating it, the temperature of 'thejbinder delivered iromthe distribution orifices will be about the same as that of the bulk supply in the tank 2. Heat losses will 'be proportionately less than if a small volume, only sufiicient to supply the quantity ne ded for d str tion, w e s pl Should it be desired to discontinue the delivery of binder from thepsystern, it is merely necessary to slide the discharge sleeve 12 over the distribution conduit 9 :to the position shown in Fi u e and th eu on. e po tion of th binder wil b pumpe thro h the d st u i n rifi and the remaining portion will be delivered through the discharge .end 1.! of the distribution conduit. all of th li u fl win h ou h t return'line, back to {the tank 2. With the distribution conduitin the position shown in Fig- 1 wi h i s d s har end Ji dispose osely adjacent to .the plug 11, free iiow of the binder through .theconduit will ,be impeded, even though the valve 20 be opened to permit relatively free circulation of the binder. This restriction to free flow will insure that an adequate portion of the binder will pass through the distribution orifices into the discharge sleeve [2 to insure against any congealing or other restriction of them.

When it is desired to resume operations, applying binder to cork granules, the sleeve l2 may be moved to the position shown in Figure 3, as previously mentioned, and instantly heated binder will be distributed through the distribution orifices l onto the cork particles, the volume being adjusted by control of valve 20.

It will be noted by reference to Figure 1 that the packing I 4 engages the outer periphery of the distribution conduit 9; and that, when the sleeve I2 is moved relative to the distribution conduit 9, there is a wiping action which tends to clear any accumulations of binder surrounding the orifices. In addition, there is a substantial suction effect created by movement of the sleeve [2 with respect to the distribution conduit 9 from Figure 1 position to Figure 3 position which tends to clear any impediments in the distribution orifices.

While in the diagrammatic showing of Figure 1 the sleeve I2 is arranged for manual displacement with respect to the conduit 9, such movement may be effected mechanically, hydraulically, by air cylinder, electrically, or otherwise.

While the invention has been described in conjunction with an arrangement for the distribution of a heat-liquefied binder onto cork granules, it will be understood that the same is not limited thereto, for the invention will have general applicability where it is desirable to maintain a constant flow of fluent materials, whether heated or not. For instance, the invention may be found to be useful in systems where materials dissolved in or carried by highly volatile vehicles are to be distributed and the problem of maintaining a circulatory movement of the material is present. Other applications of the invention will be apparent to those in the art.

We claim:

1. In apparatus of the class described, the combination of a container for the bulk supply of material to be distributed, a circulatory system including a distribution conduit having an inlet opening, a distribution orifice, and a discharge opening therein, a discharge sleeve in communication with said discharge opening and movable with respect to said conduit to bring said sleeve from a position remote with respect to said distribution orifice into a position surrounding said distribution orifice and spaced therefrom for the delivery of material therefrom directly into said sleeve, a return line to said bulk supply from said discharge sleeve, and means for continuously circulating material through said system.

2. In apparatus of the class described, the combination of a distribution conduit having an inlet opening, a distribution orifice, and a discharge opening therein, means for supplying heated material under pressure to said distribution conduit in a. volume in excess of that to be delivered from said orifice, and a return line receiving excess material from said distribution conduit, said return line including a discharge sleeve movable with respect to said conduit from a position surrounding said distribution orifice with the same in open communication with said sleeve to a positlon remote therefrom with said distribution orifice exposed for normal distribution of material therethrough and means connecting said sleeve to the other portion of said return line in both of said positions.

3. In apparatus of the class described, the combination of claim 2 with means for restricting the flow of material through said discharge opening when said conduit is in a position surrounding said orifice to insure the fiow of material through said orifice as well as through said discharge opening,

4. In apparatus of the class described. the combination of an open-ended distribution conduit having a distribution orifice and an inlet opening therein, means for supplying heated material under pressure to said distribution conduit through said inlet opening in a volume in excess of that to be delivered from said distribution orifice, and a recirculation sleeve larger than said distribution conduit constructed and arranged to receive therewithin the open end of said distribution conduit and slidable with respect to said conduit to a position surrounding the distribution orifice thereof with the same in open communication with said sleeve when said sleeve is in one position and to connect only the discharge end of said distribution conduit with said sleeve for the reception of excess material delivered to said distribution conduit in another position with said distribution orifice exposed for distribution of said heated material.

5. In apparatus of the class described, the combination of a distribution conduit having an inlet opening, a distribution orifice, and a discharge opening therein; a supply line connected to said conduit at said inlet opening for the delivery of material to be distributed; means for feeding to said supply line material in excess of that to be distributed through said distribution orifice; and a discharge line connected to said discharge opening of said distribution conduit for reception of excess material delivered to said conduit, said discharge line including a discharge conduit and a sleeve connected to said discharge conduit and slidable over said distribution conduit to enclose said distribution orifice for free delivery of material through said distribution orifice to said sleeve and through said sleeve to said discharge conduit.

6. In apparatus of the class described, the combination of claim 5 and a valve in said. discharge line for controlling the volume of material distributed through said distribution conduit.

7. In apparatus of the class described, the combination of claim 5 and means attached to said sleeve and movable therewith and engageable with said distribution conduit for clearing the surface of said conduit surrounding said distribution orifice.

WASHINGTON H. PHILLIPS. GEORGE E. GARD.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 49,310 Seiberlich Aug. 8, 1865 332,329 Dahn Dec. 15, 1885 751,612 Case Feb. 9, 1904 1,191,607 Mills July 18, 1916 2,123,604 Johnson July 12, 1938 2,301,496 Aldrich Nov. 10, 1942 2,378,184 Carlson June 12, 1945

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