US2802330A - Textile mill spindles - Google Patents

Description

Au l 13, 1957 J. D. GLEITZ ETAL 2,802,330

TEXTILE MILL SPINDLES Filed April 2, 1954 INVENTORS Jf/PGME D. 42 5/ T2 A. J. MOK/LTON United States Patent 6 TEXTILE MILL SPINDLES Jerome D. Gleitz, Pepper Pike Village, and Lloyd Jackson .Moulton, Mentor, Ohio, assignors, by mesne assignments, to Curtiss-Wright Corporation, Marquette Metal Products Division, Cleveland, Ohio, a corporation of Delaware Application April 2, 1954, Serial No. 420,491

4 Claims. (Cl. 57-130) The invention relates. to an improved composite metal blade and whorl unitof a textile mill spindle, consisting of a steel shaft for rotary support by a bolster, a barrel of light weight metal, such as aluminum, properly configured to support a tube type bobbin, and a steel whorl for driving the spindle, all rigidly secured together as by press or shrink fitting methods on a common longitudinal axis. The blade and whorl unit hereof is of a known specific type in which a tubular lower end portion of the (e. g.) aluminum barrel is tightly held by and between a relatively rigid sleeve portion of the whorl (called the acorn) and the shaft, which latter occupies an axial bore of the barrel and extends above the plane of the top end of the acorn for local reinforcement of the relatively weak aluminum and to control flexure of the bobbin supporting portion generally of the spindle.

In the above outlined type of composite metal spindle, the parts must be concentric within extremely narrow limits for the sake of proper dynamic balance; the com ponents (at least the shaft and whorl) must bear permanent precise axial relationships to each other; the necessarily exposed joint between the whorl and the aluminum barrel must be tightly closed, presenting no fissures or rough or sharp surfaces such as can either snag went the filament stockor yarn, as during placement and dofiing of bobbins, and the upper free end or bobbin supporting portions of the spindle must strongly resist fiexure. Further the exposed surface portions next to the joint between the whorl and aluminum must, for desirable operation, be defined by mutually flush smooth surfaces of the aluminum and the steel, and the aluminum adjacent the joint should be guarded by the steel from percussive contact by the bobbins which, at their lower ends, usually have metal ferrules that are much harder than the aluminum. The general object of the present invention is to provide a dynamically balanced spindle construction of the above outlined type capable of being economically and precisely manufactured .in high quan- Y tity. Other objects will become apparent from the following description of the preferred form of spindle as shown in the accompanying drawing wherein:

Fig. 1 is a reduced scale assembly view, partly in central longitudinal section, showing the present subject spindle with a tube type bobbin thereon (diagrammatically represented).

Fig. 2 is an enlarged scale, fragmentary sectional view showing portions of the steel shaft, the partly finished aluminum barrel, and the partly finished steel whorl.

Fig. 3 is a view similar to Fig. 2 showing the sam parts fully finished.

Fig. 4 is a fragmentary View similar to Fig. 3 showing a modified form of joint between two components of the spindle.

Referring particularly to Fig. 1, the shaft I (assumed to be high quality uniformly hard steel) has a suitable circular surface 3 for engagement with the bolster bearing (not shown) and a precision finished footstep-engaging, generally conical, lower end portion 4. The steel whorl ice 5 has the usual smooth circular surface 6 defined in part by the usual flange formations 7 and 8, and has an integral acorn or sleeve portion 9. The aluminum barrel 10 (preferably forging quality aluminum alloy) is shown as tapered upwardly from a region close to the top of the whorl acorn to a bobbin supporting and driving tapered circular seat 10a. the bobbin B rests firmly on the seat 10a and the lower hollow end of the bobbin loosely encircles the whorl acorn portion 9 around and below a bobbin-piloting surface portion 27 formed on the acorn near its top end and which constitutes an annular ramp acting to guide the lower end of the bobbin into approximately centered relation to the spindle as the bobbin is placed on it. Seat 10a is of high wear resistance (e. g. may be a steel cap for'barrel 10).

In Fig. 2, showing the semi-finished whorl and barrel blanks 5x and 10x respectively, and an upper portion 2 of the fully finished shaft 1 within an axial bore 11 of the barrel blank, it can be noted that the acorn portion 9x of the whorl blank is of oversize diameter relative to the finished contour of the acorn, the latter being indicated by broken lines at 9. The oversize relationship of the barrel blank 10x, in respect to the finished dimensions of the barrel 10, is similarly shown or indicated.

The barrel blank 10x is tightly taper fitted into the whorl blank 9x as by formation of smooth uniformly tapered mating surfaces 12, 12' on blank 10x and 13 on blank 9x. The degree of taper is any suitable locking angle relative to the rotational axis of the spindle. Taper surface portion 12' on the barrel blank extends upwardly into exposed position beyond the top end or rim portion 9y of the whorl blank sleeve portion 9x. The upper and lower mating taper surface bearing areas are indicated 14 and 15, being defined, in part, by a generally reduced diameter or relief formation 16 on the barrel blank, resulting in an annular clearance space 17 of considerble length when the members are force fitted together. Thus the radial locking pressures which may be obtained with a given amount of axial assembly force are increased over what the pressures would have been in case full length complementary taper fitting surfaces (same total length) had been used. Additionally, by provision of axially separated bearing areas, such as illustrated at 14 and 15, the steel of the whorl Sand the aluminum of the barrel 10 can flex independently of each other as has been found effectual, when the component metals have a marked difference in elasticity, in preventing axial relative creeping movement of interference fitted telescoping members incident to application of strong flexing forces on the assembly.

Upper shaft portion 2 (for convenience stub portion) is in interference fitted relationship to the axial receiving bore 11 of the barrel (blank 10x) at axially spaced apart lower and upper bearing regions indicated at 20 and 22, the axial spacing being achieved, in the illustrated arrangement, by a portion of a counterbore 23 surrounding a reduced diameter upper end portion of the shaft (partially illustrated). The relief around the shaft aiforded by counterbore 23 extends above and below the plane of the top of the acorn 9* of the finished spindle at which region the flexure resistance of the spindle changes more or less abruptly. due to the relative rigidity of the steel whorl. When the shaft stub 2 is force fitted into bore 11 the upper relatively reduced diameter portion of the shaft stub, which needs to be somewhat tight in the bore at 22 in order properly to control flexure of the spindle, cannot cut metal from or otherwise deleteriously affect the metal of the portion of the barrel bore 11 which is designed to receive the relatively lower portion of the shaft stub, as at: interference fitting bearing region 20. 7

An internal upper surface of.

spindle so that the aluminum is continuously subjected tooutward and inward radial pressures by the steel parts during the operating life of the spindle. During assembly of the components described above (manner of assembly given later) it is possible to secure a'tighter gripping of the extreme lower end portion of the aluminum barrel be tween the hard steel shaft and the whorl (maximum stress region due to juxtaposition of the bolster bearing) than at any region thcreabove and without having to effect any unusual or difficult maching operations on the parts such as would lead to excessive cost.

Referring to the illustrated flush joint surface arrangements'Z'S and 25a, as illustrated by Figs. 3 and 4 (two different forms), one advantage of the construction is that a butt type joint is avoided. A butt type joint necessarily involves considerable reduction in diameter of the aluminum barrel Where it enters the whorl acorn (thus an especially abrupt change in flexure resistance of the spindle at the joint). Another advantage (over prior practice) is that the exposed marginal surfaces adjacent the joint line (26 and 26a Figs. 3 and 4 respectively) do not give rise to an outwardly exposed sharp or jagged feather edge around the top of the whorl acorn such as would occur if an attempt were to be made to eliminate an exposed upwardly facing annular shoulder at the top of the acorn by forming a bobbin-piloting generally conical surface around the top of the acorn and which surface, in the completed assembly, extends into acute angular relationship to the peripheral external surface of the aluminum barrel all around the barrel. A feather edge cannot be so formed on the acorn rim or top portion without sometimes presenting jagged surfaces which can cut the yarn or at least collect lint and the like.

Fig. 3 shows the result of machining away of the excess metal of the blanks 9x and 10x, which is done after complete assembly per Fig. 2, while the blanks are supported on the spindle axis (using bearing surfaces 3 and 4, Fig. l, of the shaft 1 and a center socket 30 formed on the top end of the spindle in true axial alignment with the shaft, to maintain concentricity of external spindle surfaces with said axis). Final finish is preferably effected by grinding. The bobbin guiding ramp 27 around the whorl acorn, as shown in Fig. 3, is of curved contour upwardly to the joint line 26 where, as shown, it merges into (i. e. is flush with) a reverse curve 28 on the aluminum barrel 10. The bobbin piloting or guiding ramp 27a, Fig. 4, is operatively similar to the ramp 27 of Fig. 3 except that the major portion of ramp 27a is definitely conical, the uppermost exposed flush joint surfaces, directly adjacent joint line 26a, being formed as by an appropriately contoured grinding tool operating to cut across the interface surfaces of the aluminum and steel at a greater angle with reference to the interface surfaces than in the case of Fig. 3.

At the upper left of Fig. 3, a portion of'a conventional metal ferrule B on the bobbin B is shown as though purposely moved to a point approximately as close as possible to the joint line 26; and it is evident that likelihood of the ferrule B (or any other portion of the bobbin) striking or defacing the aluminum exposed at curve surface 28 adjacent the joint line 26, during loading of the spindle and in dofling, is practically nonexistent. A typical mounted position of the bobbin on the spindle is partially illustrated at the right of Fig. 3. The ramp and joint defining surface relationships according to Fig. 4 similarly protect the aluminum of the barrel 10 from being damaged by the bobbin.

The preferred procedure in assemblying the parts (shaft 1, barrel blank 10x and whorl blank x) is to support the shaft and whorl blank rigidly against axial movement in a direction toward the footstep end 4 of the shaft and in their proper axial and concentric spaced apart relationship, and then to force the barrel blank into place as by a single operation of a press. In production, the shaft 1 is supported in the press at the footstep end 4 of the shaft and laterally at its bearing portion 3; and the inner axial shoulder 32 (Fig. 2) of cavity 31 of the whorl blank 5x rests firmly on a suitable rigid support in the press. Thus, even though metal parts which are joined, in high quantity production, by taper fitting are inherently subject to some axial variation in relative position, the procedure hereof, as just described, assures maintenance of the whorls '5 and footstep ends 4 of the shafts of various lots of spindles in precise uniform axial relationship; and, since the bobbin carrying surface portions of the barrel and whorl are formed later, any desired precision in axial relationships for bobbin support can be readily accomplished.

The center socket 30 in the top end of the barrel blank 10x (or its cap piece if it has one as mentioned earlier) is next formed on what will be the true rotational axis of the spindle, as by supporting the assembly in an appropriate chuck, vise or the like which engages only precisely formed surfaces on the projecting portion of the shaft and thereby holds the shaft axis aligned with the center socket forming tool (not shown). Afterward the remaining operations necessary to finish the spindle are done while the rigid assembly (1, 5x, 10x) is held on center through the shaft and socket in accordance with common machining practice.

The above described taper fitting of the steel whorl around the lower end portion ofthe aluminum barrel (aside from specific features already described) has several distinctive operating advantages over taper fitting of a steel shaft into a mating socket in an aluminum barrel as already known in the art. By way of summary, or partly so, one advantage is that the subject construction enables very accurate axial relationships to be maintained in quantity production between the shaft and whorl.

despite the well known inherent limitations of taper fitted metal parts. In the case of employing a taper fit between the shaft and barrel, even when the shaft stub to be inserted into the barrel is made large in diameter, the diameters of the interfitted parts are small in comparison with those involved in taper fitting of the whorl to the barrel, hence likelihood of variation in axial relationships in the latter case is of a different order, being decreased by larger surface contact per inch of length in contact.

A further important advantage is involved with the fact already outlined, namely that when the spindle is mounted in its bolster and the upper end of the spindle is subjected to strong lateral force, the highest internal stresses will occur at the base portion of the composite structure, i. e. just above the bolster bearing. Assuming all the mating surfaces of the blanks or parts as herein shown and described are fully finished prior to assembly, then, when the shaft stub 2 is inserted into its receiving bore 11 of the barrel blank 10x, the relatively small diameter and relatively thin walled lower end portion of the relatively soft barrel blank is always slightly expanded radially outwardly to some extent. Thus when the mating taper surfaces 12, 12', 13 are finally forced together, greater radial'pressures will be exerted between the surfaces which form the lower bearing region 15 than between the surfaces forming the upper bearing region 14. concomitantly the shaft 1 in the plane of the bearing region 15 will be somewhat more firmly gripped by the adjacent aluminum surface than it was as a result of its own press fitting into the barrel bore. Thus the above just described advantage largely offsets the tendency of press fitting of steel into aluminum to produce a weak joint when, inter alia, large tolerances are used.

Still another advantage of the present construction is that it lends itself economically to shrink fitting of the tapered surfaces togetherwithout having to subjectthe aluminum to abnormally high temperatures or the parts to be so fitted together to a high temperature difference. The shaft 1 and its receiving bore are necessarily of small diameter, for which reason it would be costly to obtain the necessary temperature difference such as would enable shrink fitting of the shaft into the barrel; and if the aluminum is heated above critical temperatures in the operation its strength is impaired. On the other hand the surfaces involved in shrink fitting of the whorl 5 onto the barrel are of relatively large diameter and the steel of which the whorl is always made can safely be heated to appropriate above-normal temperatures for obtaining an operatingly permanent adequately tight interference fitting of the parts.

We claim:

1. A composite metal, textile mill spindle blade and whorl unit, comprising a one piece hard steel shaft having a footstep end portion and a bolstenbearing-engaging circular surface between its ends, a barrel of light weight metal exteriorly formed to support a bobbin and having a bottom axial bore in interference fitted gripping contact with a portion of the shaft lying above its bolsterbearing-engaging surface, and a substantially rigid steel whorl telescoping the barrel and in interference fitted gripping contact with a lower end portion of the barrel, characterized in that the mating surfaces of the shaft and its receiving bore in the barrel are principally cylindrical, and the mating surfaces of the barrel and whorl are principally tapered and of decreasing diameter toward the footstep end of the spindle, further characterized in that the tapered mating surface contact of the whorl and barrel comprise two bearing regions of tapered surface contact, one adjacent the bottom of the barrel and one adjacent the top of the whorl, said regions being axially separated by a clearance region all around the barrel and defined by radially separated peripheral surfaces of the barrel and whorl.

2,. The spindle construction according to claim 1 wherein the mating interference fitting surfaces of the shaft and barrel bore comprise regions of bearing contact radially opposite both said axially separated taper bearing regions and another separate region of bearing contact between the shaft and barrel bore upwardly from the top of the whorl and defined in part by a clearance space all around the shaft between it and the barrel bore which clearance space extends above the top of the whorl.

3. A composite, metal, textile mill spindle blade and whorl unit comprising a central steel shaft adapted to be supported for rotation in a bolster, a light weight metal barrel of circular cross section adapted to support a bobbin and having an axial bore in permanent tight gripping contact with an upper end portion of the shaft, and a steel whorl telescoping the barrel and in interference taper fitting contact therewith at the lower end portion of the barrel, further characterized by provision of a closed joint at the circular interface surfaces of the barrel and whorl around the upper end of the whorl, the defining exposed surfaces of the joint being flush with each other, sloped outwardly and downwardly and intersecting the upward terminal portions of the interface surfaces at an acute angle relative to the rotational axis of the spindle unit all around the unit.

4. The construction according to claim 3, wherein the surfaces of the barrel and whorl adjacent the line formed by the interface surfaces about the unit are relatively reverse curves the lower of which, on the whorl, forms a radially outwardly and downwardly sloping annular shoulder all around the unit to serve as a bobbin pilot when the bobbin is placed on the unit.

References Cited in the file of this patent UNITED STATES PATENTS 264,297 Iaquith Sept. 12, 1882 651,702 Draper June 12, 1900 1,061,266 Chapman May 13, 1913 2,463,484 Gelpke Mar. 1, 1949 2,536,618 Wood Jan. 2, 1951 2,609,254 Harris Sept. 2, 1952

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