US2329050A - Stuffing box - Google Patents

Description

lSept 7, 1943. H. R. HuMPHREYs 2,329,050

STUFFING BOX Filed Aug. 19, .1942

v Wad/Ig,

Patented Sept. 7, 1943 4A onions.A (oi. 2st-415.),

, This invention relates `toffstuiing v`boxes` for.- rotary shafts, and. morev particularly for tl'1e'pro-A peller-shafts of boats.

2Wher'e a stuffing box of the usual or conven tional type is rigidly secured toa suitablefsup port, as, for example, thev shaft log of "aiboat,

it has been found that thevibration of-lthe'- shaft frequently causesl such box to break loose' from;

thev support. In order to'remed'y this, ithas been proposed to construct-the stuing box inlA two: annular sections', one' of which is rigidly secured;- yto the support and the other of which is-longi'.y

tudinally spaced fronlthe first and carries-[the packing gland, the two'sections being connected by a .flexible tube, incapable of transmitting'v'i-l brations from one section to the other; Where,- however, asv in constructions previously proposed; such flexible tube constitutes the sole connec-z tion between the sections'off the stuffing box, difficulty has been experienced due to the fact that the frictional drag of the packing on the rotating shaft tends to exert a torsionalv strain on the tube, and twist the same."

`An objectV of the presentinvention is, there-Lf fore, to devise'a construction which,`while em`r ploying a stuffing box comprising two sections united by a flexible tube, as heretofore, provides 1 Fig.. 61 is. a transversesection` oni the 1 line Eke-63 partsbeing broken aWay. E.

Referring to. the dra Ing-.in detail; the anni offFigA, looking in: the-direction of-the- 'a-rroirvs,A

' of the boat.i'sindicated` at;v If, andthe usualtshaft log-fat 2. fSJindicatesfthepropellenshaft, shown; as .passingthrough' tifa-,usual stern bearingk Il. secured-tothe rearendfofithelog.l

' As statedin the'preamble, my'improved stinlrx'gff box-comprises itwo separately formed; annular sections.' rear` section is.v designated? by the.

referencecharacter .5! and is provided `with ai@ securingfiiange! supportedi Jupon-the endl of"v the log? and fastened the'reto-'asA by means: off lagsc'rewsf 'I-A passing' through-.Aholesf--G T means for so connecting said sections `that-novr torsional strain isY exerted on"said tube.

further object is Ytor provide a connection@ which, while achieving the above result, 'alsof prevents thetransmi'ssion' of vibrations from-one section to the other. n -:v

',I'o this end, the invention, in its preferred form, contemplates the provision of a yielding or cushioned, interlocking connection between the y adjacent ends of the stung box sections.

In order that the invention may be readily understood, reference is had to the accompanying drawing, forming part of this specification, and in which:

Fig. 1 is a fragmentary longitudinal section through the stern of a boat showing the propeller shaft and my improved stuffing box in elevation;

Fig. 2 is a fragmentary longitudinal section on an enlarged scale through the stuffing box and associated parts;

Fig. 3 isran end view of one of the stuiingbo sections;

Fig, 4 is a similar kView of the other of said sections; f

y Fig. 5 is a fragmentary transverse section subdescribed". f A 4. The L'other' orforward section offthe stuffing box is-shownat III; andl-is'formed-atitsirearenclv Y forward-end of- Ithis section of tliei stuffing boxf l `is vof ,enlarged-internal? diameter; agindicated atl 5e, andiis preferably provided with. av pain-of marginal',` long'iit'udinallyj projectingjears; or.y lugsi 8 havinga attened' inte-'mallface.l A radial? hole or openingflly isformed-in the fportionil adje,...-

cent each earfor'lug-B, for afpurpose hereinafter-f with aportion Iiia -snug'lyffittingtnevshaftv 'andi l'iavin'ganA externallsurface vwhiclifreely Atele-- scopes' inL theV portione of ltllielsection 5i This portion "Illawof the-section I0 -carresafpalr of' radially disposed screw studs II 'adapted to en ter-'thehholes'` or openings: :955i the-'section 5.` These Eholes are considerably larger than-the studs II and a yieldable bushing- "I2,ofsof-t maf 'teriaL is preferably interposed between each of the studs and the walls of the opening.

Thus the screw studs II, openings 9, in which they engage, and the interposed yieldable bushings I2, constitute a cushioned interlocking connection between the two sections of the stuffing box.

Adjacent the exteriorof the portion Illa. the external surface of the section l0 is cut away or flattened in the region of the studs II, as indicated'at I3 in Fig. 3. These flattened areas cooperate with the flat faced lugs 8 to insure the assembling of the twosections in proper angular relation, so that the studs will register with the openings 9.

' The forward end of the section I0 is preferably provided with a thickened flange I4, adapted to receive bolts I5, serving to secure a follower or gland I6 in position to hold and compress the usual packing I'I, in order to provide a water-tight joint.

stuiiing box, the studs Il are backed out into the The tube I8 is then" slipped into position over one section, andthef two sections thereupon telescoped together. By,

position shown in Fig. 3.

Owing to the simple construction and ease of assembly of my improved stuffing box, it is adapted for use on practically all sizes of propeller shafts, and entirely eliminates the difficulties heretofore encountered.

What I claim is:

l. The combination with a shaft log, of a stuiiing box comprising two separately formed annular sections having adjacent cylindrical portions of substantially the same external diameter, means forrigidly securing `one'section to said shaft log, a packing gland carried by the other Wsection, a flexible tube surrounding Said cylinmeans of a suitable tool, the studs are then" screwed outwardly so as to enter the bushed f,

openings 9, as shown in Figs. 2 and 5, and so that their inner ends are flush with or below the interior lof theportion 10a. The hose clamps are then suitably `tightenedgaround the tubing, sc as to provide a Water-tight joint. The packing gland having been removed or loosened, the assembled sectionsare then, slipped over the shaft and-the section 5 secured to` the log. Then when 4the packing glandis tightened upany leakage o f water past the 1 stufling box is e'ectively pre-y vented.` y l AIt will -be understood that the frictional drag of thepacking l1 on the rotating shaft wouldtend to exert torsional strain upon the tube l8 and twist `the same, were it notl for the interlocking connection between the sections, comprising the; studs H. These studs, however, effectively pre-.

vent any lsubstantial relative. angular displacement between the two sections, and thus protect the tube i8 from any torsional strain.

, By reference lto 2, it will be seeen that the internal diameterof the section 5 is considerably larger than thedameter of the shaft 3, so that ample; clearancefis rprovided therebetween. Al-

though` any Vibration of the shaft isof course imparted to the section ID of the stufiing box, this Vibration is .not transmitted to the fixed section 5, because ofthe fact-that the only connection between the `sections is through the flexible tubing iliand the yielda-ble bushings or cushions` l2. Thus; While I employ a piece of flexibletubing for connecting the sections, I Provide means for preventing any torsional strain from being ex erted on thistubinQ, Ysuchmeans at the same time preventing the transmission of vibrations from one section to theother. f Y.

drical portions and forming a water-tight joint therewith, and a cushioned interlocking connection between said sections.

2."A stufling box for rotary shafts comprising a pair of annular sections having straight sided telescoping adjacent ends by which they are held in substantial alinement and formed with cylindrical outer surfaces of substantially the same diameter, means for yrigidly supporting one section, a packing gland carried by the other section, a `flexible tube surrounding and tightly fitting'v said cylindrical surfaces, and means so connecting said telescoping endsl as to .prevent both substantial relative angular displacement thereof and trans-- mission o fvibrations from one to the other.

V 3. A; stuffing box for rotary shafts comprising a pair Qfiannular sections having loosely telescop ing adjacent ends fand, formed. with cylindrical.l outersurfaces'of substantially thesame diameter,y means for rigidly supporting one section, a pack, ing gland carried by the other section, a flexible 1 tube surrounding andA tightly fitting said cylindrical surfaces,l and means connecting saidtelef scoping ends `comprising a radial stud carried by one section and engaging an opening in the other section larger than said stud, and a yieldable bushing interposed between said walls of saidgopening.

4, The combination with a rotaryshaftof a stufling box through which said shaft passes, said stung box comprising two separately formed stud and the annular sections having alined cylindrical sur;

face s, a flexible tube surrounding and secured to saidcylindrical surfaces, means for vrigidly supporting `cneof said sections, A a packing gland carried by the other section and snugly engaging said shaft, wherebyA the frictional drag on said packing gland Wouldvtend to 4twist said tube, and means for; limiting the torsional strain exerted on said tube. i Y.

' HANNAR. HUMPHREYS.

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