US1764909A - Centrifugal drier - Google Patents

Description

June 17, 1930.

c. w. TERWILLIGER 1,764,909

CENTRIFUGAL DRIER ts-Sheet 2 i 2 Shee Filed NOV. 28, 1927 vwemtoz Patented June 17, 1930 l' i 'tireur orifice i cnurnmuean paran Y application led :November 28,' 1927.

rl"his invention relates -toy centrifugal driers or extractors and more particularlyv refers to improvements inthe construction ofextractors such as used for drying clothes where a relatively high rate of speed must be used.

The primary object of this invention is to provide a novel and improved arrangement litt ` improved arrangement loit for the u per party of the i" for yieldingly guiding the upper end of the upright shaft or spmdle carrying the basket or container, said arrangement being designed so as to tend to continuously counterbalance the tendency of said shat 0r spindle to deviate from the geometrical axis of rotation or itspoint of support due` to uneven loading of the tainer',

Another object of this invention is to provide practical and edective means for ,reducing or correcting vibrations such as are usually induced in 'the basket shaft or spindle inmachines of the character mentioned, due tol the practical impossibility of uniformly distributing the load within the basket or container. l

A further object is to provide a novel and yielding bearing basket shaft or spindle o a centrifugal drying machine, adapted to be built as a complete unit in itself, and adapted to be mounted on Ina- ;chines already in use without entailing any material changes in their structure;

@therpobjects and advantages of the=present invention willmore fully appear as the description proceeds and will be set forth and claimed in the appended claims.

Centrifugal drying machines generally? comprise a bowl or casing mounted on a vertical stand, al vertical shaft or spindle basket or coni running centrally of said stand, and projecting within the bowl, a basket orcontainer carried by the upper end. of said shaft with# in said bowl, and means for imparting rotation to the shaft. Y

The system is normally balanced, the cen-V gravity of the basket vor container coinciding with the center ofthe shaft, but

an unbalanced condition fis created whenever the load is inserted'into the basket,

'tensity that v powerconsumption l deformation oit' Serial No. 236,258.

-because it is practically impossible to 'evenly distribute said load. v

Due to this condition, considerable lateral stresses are created upon the shaft when the same is rotated at high speed; and the forces thus enerated are 'of such an in- 1t has been found impractical to run the upper end of the shaft or spindle close'to the basket through a bearing of Ythe ordinary ln'nd, without 'giving rise to destructive friction and Wear.

Accordingly, it has become customary to mount the lower end of the shaft vor spindle through an elongated bearing and to allow the upper end thereof to become deflected and to rotate in a conical path about the axis of gyration resulting from the load conditions and speed.

Attempts'have been made towards correcting the ensuing vibration 'of the machine to a certain extent, for instance, by providing-the upper end of the shaft or spindle witha rubber ring acting as a bumper absorbing part of the lateral shocks; but insofar as l am aware, no eiiective means has, as yet, been found to correct the tendency to'vibration to any material extent, so that as ,aY result dangerous conditions are still attached to the operation of 4these ma-` chines, increased power is needed for their operationf'and injurious wear is induced -in thefbearingsfdue tollateral thrust of the sha lateral displacements of the shaft vare largely prevented not at the expense of increased Y and wear, but by the elastic lbodies acting as absorbers, arranged to exert their action in a continuous and practically uniform mani ner, creating but a limited amount of frictiona v -The arrangement is such that'while the lateral displacements of the shaft are not entirely eliminated, they arel reducedto a considerable extent so that no excessive demands are made upon the driving and the .Y

wearing parts of the machine and smooth.YV j

running operation is assured.

Y My inventionwill bebetter understood by 100 stand, and in the same is rotatably referring to the 'accompanying drawings, in which :l

Fig. 1 is a sectional view in elevation of a centrifu al extractor of a conventional type embodying my invention;

Fig. 2.is a fragmentary sectional view in elevation of the same in an enlarged scale, showing the general construction of my im-4 proved bearing; y

Fig. 3 is a plan sectionaly view through line 3-3 of Fig. 2; and

Fig. 4 is a plan sectional view through the bearing shown in Figs. 2 and 3, illustrating the positionof its various parts when the shaft is laterally displaced from its normal center of rotation.

In the drawin s, 10 designates the bowl or casing provi ed with acover 11land mounted on a stand 12. A bearing 13 extends upwardly from the base 14 of the mounted a vertical shaft 15, the upper en of which projects within bowl 10.

Saidl upper end of the shaft carries an open top basket or container 16 which is usually perforated in order toy permit the liquid extracted from the material inserted in the basket or container to be forced out by centrifugal force, to be collected at the bottom of the bowl. Rotation may be imparted to the shaft by means of a pulley 17, mounted at the lower part of leaving a considerable length of shaft 15 between-said pulley and the hub 18 of the basket. N

Ordinarily that part of the shaft which is designated by 15 is left free to obey the lateral impulses due to the unbalanced condition of the load; but as stated before, it is desirable in practice to limit as much as possible, the lateral displacements of the upper end of the shaft without however, creating new and antagonistic conditions which might nullify the advantages to be gained or which might in fact be open to still more serious objections than the conditions originally existing. l

I accordingly provide a specially designed yielding bearing 4for the upper end o the shaft which is shown in the drawing as being mounted in a special frame 19 provided with depending brackets 20 adapted to be secured onto stand 12 in any suitable manner,for instance by means 0f, screws 21 as shown. j

Frame 19 consists of a lower plate 22, an upper plate 23 and four corner blocks 24, 25, 26, 27, joining the two plates, forming four passa es 28, 29, 30, 31, at right angle toone anot er between said up er andlower plates. The central portion o the frame is open from top to bottom, the openingthus formed being square in form as indicated at. 32.

The center of said opening 32 coincides said shaft, 37

with the junction point o f the central lines of passa es 28, 29, 30, 31, and the frame is so place in position that .said center coincides with.the axis 33 of the lower end of the shaft and bearing 13.

lA. bushing for the upper end of the shaft is inserted through said opening 32, said bushing comprising a body portion 34 which is square in section and which is preferably somewhat lon er than the distance between the lower sur ace of plate 22 and the upper surface of plate 23, a flange 35 laterally extending -from the upper end of said body portion, the outline of said flange being also preferably square, a threaded portion 36 downwardly extending from said body vportion and a flanged nut 37 mounted on said threaded portion.

Said bushing has a central opening for the upper end of the shaft 15 and is normally mounted so as to maintain the shaft in a vertical position. However, the body portion 34 of the bushing is smaller in section than opening 32 so centrally spaced with respect to frame 19,-

a clearance 38 will remain all around between rthe sides of opening 32 and the sides of body portion 34.'

Said body portion is also preferably provided with a peripheral groove 39 about midway between flange 35 and flanged nut Through each one of the passages 28, 29, 30, 31 are inserted resilient means for maintaining the bushin in its proper position, said means prefera ly comprising a rubber block 40, a cap 41 for the inner end thereof, said cap being adapted to slide in a radial direction through its respective passage, and a rear plate 42 bearing against said rubber block.

The outer end of each one of said passages 28, 29, 30, 31, is closed by a plate 43 which is secured to the frame by means of screws 44, and through the center of said plate projects a screw 44 provided with a check nut 45, exerting pressure 'against plate 42 and maintaining therefore cap 41 in abutment against the opposite side of body portion 34.

Each cap 41 is preferably provided with a lug 46 projecting within groove 39, sovthat axial displacements of the bushing are pref vented thereby.. As stated before, the section of body portion 34 of the bushing is smaller than opening 32, so that the upper part 15 of the shaft or spindle may be laterally displaced with respect to axis 33, unless said lateral displacement is prevented by other'means. Screws 34 are so adjusted that when the-shaft is stationary, the pressures exerted b rubber blocks against caps 41, neutra 'ze one another, maintaining the center of alignment of the shaft.

Howeverpwhen the machine is rotated at that when the bushing is l relatively high speed with an unbalanced load in the basket, the upper end of the shaft will acquire a tendency to lateral displacement, as before explained, and said tendency should be checked or to a certain extent counterbalanced without causing undue frictional resistance against the surface of the bushing.

By virtue of the arrangement described, the bushing following the lateral displacements of the shaft bears in succession against one and then the other of caps 41, causing the compression of their respective rubber blocks 40, which thus act as absorbersl of the lateral thrust exerted by the shaft.

The relative arrangement of passagesQS, 29, 30, 3l, is such that the lateral displacements of the shaft are transmitted at all points to the rubber blocks, because when` the shaft is displaced directly in line with the central line of any one passage the bushing will bear against the cap sliding within said passage, and as soon as the transversal displacement of the shaft is directed -at an` angle to said line, the bushing will simultaneously bear against said cap and also i against-the cap sliding through the next .passage, until when the lateral the shaft is directed at 90O to its former disisplacement yof placement the bushing bears entirely against the second cap, the central line of which is now in alignment .with the direction of displacement ofthe shaft.

This point is clearly illustrated in Fig. 4 Where the center 47 of the shaft is shown as being displaced from its normal axis 33 at 45o between cap 41 and cap 41. In said position, as shown, the bushing bears simultaneously against the surfaces of both caps so that both rubber block 40 and rubber block'40 are compressed to the same extent. As the center 47 of the'shaft continues to rotate about axis 33, say for instance,- in a` counterclockwise direction, the pressure exerted against cap 4l decreases and the pressure exerted against cap 4l increases, until the pressure exerted against cap 4l becomes nil and the pressure is borne entirely by cap 41".

It will be observed that while lugs 4 6 preventaxial displacement of the bushingA with respect to the frame, they do not prevent the lateral displacements of the bushing because groove 39 extends all around the bushing and its top and bottom surfaces can slide over the surface of said lugs.

As stated before, body portion 34 of the bearing is somewhat longer than the distance separating the lower surface of plate 22 from the upper surface of plate 23, so as to prevent wedging action by the inner surfaces of the flanges coming to bear against the outer surfaces of said plate when the bushing is displaced from its normal position due to the lateral displacements of `regulate the amount o the shaft;v although it is obvious that only `a very small clearance needs thus be protically be considered as taking place at rightv angle to the direction of axis 33.

For the device to beA operative, it is important that opening 32 be larger than the section of body portion 34, because if such were notJ the case, the structure would become rigid instead of laterally yielding in character and the advantages of the arrangement would be lost. The adjusting screws 44 are also an important feature of the device, because by properly adjusting said screws it is possibleA to adjust the position of the shaft with the utmost accuracy; furthermore, it is also possible thereby to pressure exerted against the shaft.

Plates 43 can be removedwith ease whenany time without interfering with the oper- I ation of the machine. If desired, the action of the rubber blocks could be supplemented or substituted by that of springs, but in practice I have found the rubber blocks to provide a smoother and more satisfactory.-

operation.

My improved arrangement can be em-v bodied in the construction of new machines and in such case, frame 19 may be made integral with the stand or with the, bowl portion of the structureif desired; but if the device is made in the f orm of a complete detachable unit-as shown, the samecan be readily installed in existing machines merely. by properly designing the attachingmeans therefor. i

he sliding caps must be so designed as to lbe inwardly movable to follow the displacementsof the bushing, without interfering with one another, and this can be obtained either by making the width of said caps less` .than the width of the body portion 34 of the bushing, or else by making the width of the caps equal to that of the said body portion 34 as shown, or larger andby cutting off the inner corners of said caps as shown at 48. In all cases the various elements of which the structure is composed, must be freely movable without interfering with the action of the other elements.

It is obvious that devices embodyingmy invention may be produced differing in many details from the arrangement shown Without departing lfrom the inventive idea. For instance, while I have shown and described a bushing havin four sides in combinaticn with four yiel ing members bear-l ing against said sides, it w1ll be understood for,

Athrough said frame allowing lateral dis` that it is possible to use bushings having a different outline in combination with a different number of resilient members, as long as said members are not less than three in number. l The drawings should therefore, be understood as being intended for illustrative purposes only and not in alimiting sense. I accordingly reserve myself the right to carry my invention into practice in all those ways and manners which may enter, fairly, into the scope of the appended claims.

I claim:

1. In a machine of the character specified, the combination, with a bowl, a stand therea normally vertical shaft, a basket within said bowl carried by said shaft, and la bearing for the lower end of said shaft, of a frame surrounding the upper part of said shaft, a bushing for said shaft i inserted through said frame, said bushing being provided with a peripheral groove, an opening placement of said shaft and bushing, and resilient means carried by said frame, and bearlng against said bushing, ysaid resilient -means interlocking with said -groove and being guided to move radially of the normal axiso rotation of said shaft.

2. In a machine of the character specified, the combination, with a bowl, a stand therefor, a normally vertical shaft, a basket within said bowl carried by said shaft, and a bearing for thelower end of said shaft, of a frame surrounding the upper part of said shaft, a bushing for said shaft inserted through said frame, said bushing being pro- `vided with avperipheral groove, an opening through said frame allowing lateral displacement of said shaft and bushing, and resilient means carried by said frame, and bearing against said bushing, said resilient means being guided to move radially of the normal axis of rotation of said shaft, said resilient means bein restrained from moving axially of said frame, and interlocking with said groove so as to prevent axial displacement of said bushing in relation to said means, while permitting lateral displacement thereof in relation to said frame.

3. In a machine of the character specified, the combination, with a bowl, a stand therefor, a normally vertical shaft, a basket within said bowl carried by said shaft, and a bearing for the lower end of said shaft, of a frame surrounding the upper part of said shaft, a bushing for said shaft inserted through said frame, said bushing having a polygonal section and being provided with a peripheral groove, an opening through said frame allowing lateral displacement of said shaft and bushing, passages radially extending through said frame opposite the side surfaces of said bushing, and resilient members slidable within ,said passages, bearing against said bushing, and interlocking with said groove.

4. In a machine of the character specified, the combination, with a bowl, a stand therefor, a normally vertical shaft, a basket within said bowl carried by said shaft, and a bearing for the lower end of said shaft,.of a frame surroundin the upper part of said shaft, a bushing or said shaft inserted through said frame, said bushing having a polygonal section and being provided with a peripheral groove, an opening through said frame allowing lateral displacement of said shaft and bushing, passages radially extending through said frame opposite the side surfaces of said bushing, and resilient members slidable within said passages, bearing against said bushing, said resilient members interlocking with said groove, and being restrained from moving axially of said frame.

5. In a machine of the character specified, the combination, with a bowl, a stand therefor, a normally vertical shaft, a basket within said bowl carried by said shaft, and a bearing for the lower end of said shaft, of a frame surrounding the upper part of said shaft, a bushing for said shaft inserted through said frame, said bushing having a polygonal section and being provided with a peripheral groove,` an opening through said frame allowing lateral displacement of said shaft and bushing, and interlocking with said groove, passages ing through said' frame opposite the side surfaces of said bushing, resilient members slidable within said passages, bearing against said bushing, and means'preventing axial radially extenddisplacement of said .bushing in relation tosaid frame.

6. In a machine of the character specifled, the combination, with a bowl, a stand therefor, a normally vertical shaft, a basket within said bowl carried by said shaft, and a bearing for the lower end of said shaft, of a frame surrounding the upper part of said shaft, a bushing for said shaft inserted through said frame, said bushing having a polygonal section and being provided with a peripheral groove, an opening through said frame allowing lateral displacement of said shaft and bushing, assages radially extending through said rame opposite the side surfaces of said bushing, resilient members slidable within said passages, bearing against said bushing and interlocking with said groove, means preventing axial displacement of said bushing in relation to said frame, and means for adjusting the pressure exerted by said resilient members against said bushin 7 'In a machine of the character specified, the combination, with a bowl, a stand therefor, a normally vertical shaft, a basket Within said bowl carried by said shaft, and a bearing for the lower end of said shaft, of

l a. frame `surroundin the u per part of said shaft inserted an opening through shaft, a bushing or sai throu h said frame,

- said rame allowing lateral displacement of said shaft and bushing, passages radially extending through said frame opposite the surface of said bushing, a member slidably inserted through each passa e, bearing against said surface, a rubber block pressing against said slidable memberf, and means for adjusting the pressure exerted by said 'rubber lblock aginst said member.

GHARL SW. TERVVILLIGER.

Images