US 2522281 A
Description (OCR text may contain errors)
Sept. 12, 1950 E. 'r. KOSKINEN 2,522,281
VARIABLE OUTLET FOR LIQUID coununs 2 Sheets-Sheet 1 Filed April 11, 1949 ATTORA/E'YJ.
Sgpt. 12, 1950 E. 'r. KOSKINEN VARIABLE OUTLET FOR LIQUID conouns 2 Sheets-Sheet 2 Filed April 11, 1949 INVENTOR Patented Sept. 12, 1950 UNITED STATES: PATENT QFFIcE Q VARIABLE vmi ii lmmmeme I: v
Einar T. KoskinenflWausau,,'Wis., assignorto D. J. Murray Manufacturing 00., Wausau, Wis, acorporation of Wisconsin Application April 11', 1949, Serial No. 86,761
The present invention relates generally-to improvements in the art of paper making and relates more particularly to improvements in the construction and operation of equipment for con-1 veying and agitating fibrous pulp stock or like.
A primary object of the invention is to provide an improved variable outlet of simple, compact and durable construction for discharging liquids or the like at varying-levels and for facilitating agitation thereof within a receptacle in a highly eflicient and economical manner. I
"In the paper making industry, it is customary practice to utilize tanks or containers for agitating and/or storing quantities of fibrous'pulp stock preparatory to converting the same to paper. These tanks or containers are commonly known as stock chests and are obtainable in (iiverse sizes to meet different requirements. Fre-' quently, it is desired to have these stock chests of extremely large size, with capacities of several hundred thousand gallons, and such large :chests are necessarily of considerable depth so as to varies considerably from time to time dependent upon operating conditions, it has generally heretofore been considered impossible to properly agitate the fibrous pulp stock within the chest' in an efiicient, economical and practical manner under such widely varying conditions of operation. This is primarily due to the fact that al though some of these large chests may operatequite efliciently when filled to maximum level,-
the horse power required to drive the stock circulating pumps, when the level drops materially below the upper delivery ends of the discharge pipe or pipes, becomes excessive and thus'prevents economical operation of the units. While it has heretofore been proposed to discharge the liquid or pulp'stock at various widelyspaced and" fixed points along these pipes through utilization of complicated Valve mechanisms operable by floats, such prior proposal has notsolved the problems because it fails to provide for discharge of the circulating liquid into the tank at any level i of the tank contents.
Itis therefore a more specific object of this invention to provide an improved pulp agitator which obviates the disadvantages attendant prior 'installations and particularly those embodying detailed description;
A clear conception of the several features con v stituting the presentimprovement, and of the modeof constructing and of utilizing pulp stock agitators embodying the invention, maybe had relatively large stock chests.
Another specific object of the present inven-' tion isto provide an improved pulp agitatingunitwherein the upright circulating pump delivery conduit or conduits automatically attain a height corresponding to the level of the liquid confined within the agitating chamber or chest.
Another specific object of the invention is to provide an improved liquid circulating system.
wherein the circulating pump or pumps are operable with minimum power consumption at all times, thereby insuring maximum eiiiciency of operation.
Another specific object of 'my invention is toprovide an improved fibrous stock agitator wherein the solution is gently circulated and i thoroughly agitated without violent disturbance, An additional specific object of my present invention is to provide "an improved liquid delivery.
duct for a circulating pump or the like which ismeet" automatically variable in length so as to varying operating conditions;'
A furtherspecificobject of the present inven' tion is' to provide an improved fibrous pulp stock agitating unit composed of relatively few parts which may be readily manufactured, quickly-and easily assembled or dismantled, and efiectively utilized at low cost.
:Still another specific object of the present in-' vention is to provide an agitator for liquid confined within a space which comprises, a liquid varying the deliveryend of said conduit to conform with thelevelof the liquid within the space. These and other objects and advantages of the" invention will be apparent from the followin by referring to the drawing accompanying and forming a partof this specification wherein like reference characters designate the same or similar parts in the various views. Fig. 1 is a more or less diagrammatic section.
through a fragment of a typical stock chest provided with conventional liquid recirculating pumps, each having one of the improved varia-' ble delivery conduitsassociated therewith, and
with. thedelivery ends of the conduits being.
shown in raised position by means of dot-anddash lines;
Fig. 2 is a top view of the assemblage of Fig. 1;
Fig. 3 is a fragmentary vertical section through one type of improved variable delivery conduit associated with an axial flow pump and showing the same in uppermost position;
Fig. l is a top v ievv of "the discharge end ofv the. delivery conduit shown in Fig. 3-, a portion of the conduit being shown in horizontal section taken along the line 44 of Fig. 3; and
Fig. 5 is a fragmentary vertical section through a modified type of improved variable delivery conduit and showing the same in lowermost position.
While the invention has been shown and described herein as being associated with a conventional axial flow type of liquid circulating pumps for continuously agitating fibrous pulp stock confined within a typical stock chest, it is not desired or intendedtothereby unnecessarily restrict or limit the scope or utility of the invention; and it is also contemplated that specificdescriptiv'e terms employed herein be given the broadest possible interpretation consistent with the" disclosure.
Referring to the drawing; the improved variable outlet is illustrated in' conjunction with a receptacle or stock chest or conventional rl'e'sign'and a plurality'of circulating pumps of cor'iventional axial flow type; but it is, or course, to be understood that the design or'construction of the tankmaybe varied and pumps oiother types may-beutilized advantageously with the invention. The
and having a belt drive? i9 associated with the outer end thereof, the belt drive I9. is adapted to receive power from anysuitable source in a well-known manner; Each. of the pumps is provided with the usual suction inlet 2U opening into the interior of the chest and. with an upwardly directed discharge 2i ford'elivering' the liquidinto the confining space 12 formed by the container walls; and. as these pumps are driven, they circulate the liquid: l3 within the chest or tank in an obvious mannen.
Withsp'ecial reference to Figs..3 and-4, the im proved variable outlet shown therein comprises; in general, an upright-discharge conduit 22 fixedly secured to the outlet or discharge end 21 of. the;-
pump l5 and forming a verticalextens-ion there for; and a tubular. liquid delivery sectionv 23 telescopically associated with the. fixed conduit. 22 for vertical movement relative. thereto, the delivery section '23 being of slightly greater internal diameter than the external. diameter of the discharge conduit" 22 to permit freedom or" movement and also being provided with an upper annular air chamber 24 forming a float for automatically varying the position or height of the delivery section 2 3 to definitely conform with the level of the liquid f3 within the space I2. To impart strength and rigidityt'othe tubular movabledeli'very section 2 3, this delivery section is formed with inside and outside walls 25, respectively extendin'g z'the length ofthe section 28 to provide a double full length wall and a second annular air chamber 21 therebetween, thus also adding to the buoyancy of the delivery section. The section 23 is preferably guided to prevent binding in its vertical movement by means of an annular series of guide and stop rods 28 fixedly secured in suitable fashion at their lower endsin spaced series to the flange 29 of the pump discharge conduit, the upper end of each rod piercing the lower wall 30 of the annular chamber 21 and being provided with an enlarged portion or head '31- co-operating with the walls of the chamber 21 to guide the section 23 and to positively stop or limit upward movement thereof'atlapredetermined position; and to aid in guiding the deliverysection 23, an annular series of equally spaced: inner guide members 32 may be securedto the interior of the inner wall 25, the guide" members 32 being. slotted or spaced from the wall 25 at 33, as shown in Figs. 3 and 4, to receive theupper end of the wallo'f the fixed discharge conduit 22".
The modifieddevice shown in: ig. 5- as emeter of the discharge conduitizz and is vertically" sliclable within the'fixedcdischarge conduit; The modified tubular delivery section 23" is also provided with an upper annular air chamber or fioat 34'," and. is likewise formed with inside. and outside walls 35', 35 respectively roviding a double wall and. auxiliary air chamber ill and strengthening as: well as adding buoyancy to thesection In the modified device of Fig. 5, the delivery section 23" is guided in its. vertical, movement by a ring. 38' embracing" and. secured to the uppersportion of the fixed conduit 22: and an: annular series of spaced. guide members 39 carried outwardly by the delivery section 23 and cooperating with inwardly directed lower flanges 40' formed on the members 39 to guide and limit the movement of the section 23-.
In operationof the improved. device, any desired quantity of fibrous pulp stock l3 may beintro'duoed' to the confining space H within the tank or container and the pumps Hi may be operated in the usual known manner to circulate the stock inwardly through the suction inlets 20 and outwardly through the. discharge conduits 22, thereby constantly gently agitating the same. While the liquid level within the tank is at or below the'up-per ends'of the fixed discharge conduits: 22', the. delivery sections 2-3,.2'3' will remain in. lowermost. positions as shown by full lines. in Fig. 1 due: tothe Weight of: these sections and force of. gravity; and. the material will thus be discharged upwardly into the tank at the level of the fixed conduitstzz by thepumps. However, as material addedtto. the supply within the confining space [2,. thereby raising the level of the. stock above the 'upperends of the fixed conduits 22', the material; will act on the floats or buoyantair'chambers' 2'4, 36, as the case maybe, and. elevate the delivery sections therewith so that the material is discharged through the delivery'sections at, or approximately at, the liquid Accordingly, through the presently proposed"- use of a stationary or fixed discharge conduit of relatively short length provided with a telescopic floating section of any required length, the horse power requirement for pumping and agitating the pulp stock is in direct relation to the level of stock in the chest; and the horse power consumption for proper agitation of the stock is only a fraction of that required with a full length stationarylpipe when the stock level is below the pipe delivery end. In addition to the saving of power resultin from the use of the improved variable outlet requiring elevation of the liquid only to the level of the supply within the tank, the stock is advantageously gently agitated during circulation thereof by reason of the discharge at approximately the liquid level at all times.
From the foregoing detailed description, it is apparent that the present invention contemplates provision of an improved agitator for fibrous pulp stock which is highly eflicient and economical in operation and which may be advantageously utilized in conjunction with tanks or stock chests of diverse sizes and designs. The improved devices comprise exceedingly few parts which may be readily manufactured and assembled of more or less standard piping, sheet metal, rods and angle irons at relatively low cost. The assembled units are also extremely compact and durable, and all parts are readily accessible for inspection, replacement or repair. Through use of the upper air chamber 24, 34, the upright circulating pump delivery conduit or conduits automatically attain a height corresponding to the level of the stock 13 within the confining space l2; and the telescopic section 23, 23' is rendered more rigid and also more buoyant by the double wall construction shown herein. Since the circulating pumps 15 are obviously operable with minimum power consumption through use of the improved devices, maximum efficiency of operation results; and the pulp stock is gently circulated throughout the tank to effectively agitate the same without violent disturbances.
It should be understood that it is not desired or intended to limit this invention to the exact details of construction or to the precise mode of use, herein shown and described, since various modifications within the scope of the claims may occur to persons skilled in the art to which this invention pertains.
1. A liquid agitator comprising, a liquid confining tank, a fixed upwardly directed liquid circulating conduit rising from the bottom of said tank, an annular float adapted to ride upon the upper surface of the liquid within said tank and having a hollow tubular depending section telescopically cooperable with said fixed conduit for conducting liquid over said float and upon said of said tank, an annular sealed fioat disposed outwardly beyond the upper open end of said conduit and adapted to ride upon the upper surface of the liquid within said tank, said float hav ing a rigid hollow circular tubular depending section telescopically cooperable with said fixed conduit for conducting liquid outwardly over said float and upon said upper liquid surface, the telescoping ciz'cular surfaces of said tubular section and of said condit being spaced apart but relatively movable while said float assumes a position. conforming with the liquid level in said tank, and a series of local float guides depending from saidiloat and slidably ceacting with the surface of said conduit opposite to that cooperating with said tubular section.
3. A liquid agitator comprising, a liquid confining tank, a fixed upwardly directed liquid circulating conduit rising from the bottom of said tank, an annular float disposed outwardly beyond and above the upper end of said-conduit and adapted to ride upon the upper surface of the liquid in said tank, said float having a rigid hollow annular depending section telescopically c0- operable with the exterior of said fixed conduit for conducting liquid outwardly over the top of said float and upon said upper liquid surface, the inner surface-of said hollow section being spaced from the outer surface of said conduit but being movable therealong while said float assumes a position conforming with the liquid level in said tank, and a series of local float guides carried by said float and coacting with the interior of said conduit.
4:. A liquid agitator comprising, a liquid confining tank, a fixed upwardly directed liquid circulating conduit rising from the bottom of said tank, an annular float disposed outwardly beyond and above the upper end of said conduit and adapted to ride upon the upper surface of' the liquid in said tank, said float having a rigid hollow annular depending section telescopically cooperable with the interior of said fixed conduit for conducting liquid outwardlyover the top of said float and upon said upper liquid surface, the outer surface of said hollow section being spaced from the inner surface of said conduit but being movable therealong while said float assumes a position conforming with the liquid level in said tank, and a series of local float guides carried by said float and coasting with the exterior of said conduit.
EINAR T. KOSKINEN.
REFERENCES CITED The following references are of record in the file of this patent:
UNITED STATES PATENTS I Date