US3798888A

US3798888A - Spinning and twisting spindle

Info

Publication number: US3798888A
Application number: US00222593A
Authority: US
Inventors: G Mandl
Original assignee: Maschinenfabrik Rieter AG
Current assignee: Maschinenfabrik Rieter AG
Priority date: 1971-02-03
Filing date: 1972-02-01
Publication date: 1974-03-26
Anticipated expiration: 1991-03-26
Also published as: GB1383373A; BE778798A; DE2114779B2; DE2114779A1; FR2124337A1; FR2124337B1; CH530484A; IT949689B

Abstract

The spindle is rotatably mounted within a sleeve by means of a neck bearing and a foot bearing while the sleeve is mounted elastically within a fixed bolster. An elastic radially symmetrical connecting element serves to mount the upper end of the sleeve in the bolster while an elastic radially symmetrical connecting member connects the lower end of the sleeve to the bolster. The lower connecting member may also support the sleeve rigidly in an axial direction relative to the bolster in some embodiments.

Description

[ Mar. 26, 1974 United States Patent 1191 Mandl SPINNING AND TWISTING SPINDLE FOREIGN PATENTS OR APPLICATIONS ,m .m aa Huh" ff n BB mm eei nm rrar GGhF 45706 60465 99999 lllli 309 2 ll 75627 77750 .9 .9 21592 5 245 9 42 5 1 u m h L t r E SE .m mm W o e W2 I ah m mw n i a h Md cf. m n m n an re h mm rzl e.- ew .1 GS RW n a w m m n v w m A .i 11 5 3 7 7 r1 r1 [22] Filed: Feb. 1, 1972 [21] Appl. No.: 222,593

Primary Examiner-John Petrakes Assistant Examiner-Charles Gorenstein Attorney, Agent, or Firm-Kenyon & Kenyon Reilly Carr & Chapin Switzerland.................v....... 1582/71 ABSTRACT The spindle is rotatably mounted within a sleeve by 3 i2 V H 4 6 B5 5 Am BO 5 Lil 3 r 1 w NO 3 M .m F QM 5 to mount the upper end of the sleeve in the bolster while an elastic radially symmetrical connecting memb [56] References Cited UNITED STATES PATENTS er connects the lower end of the sleeve to the bol- Taft Westall et al. Hargreaves et Schmid MY uu I m w Wmv l l l lJflnv l hhi'fl-ill'ill 9' 1 2 I SPINNING AND TWISTING SPINDLE This invention relates to a spinning and'twisting spindle. More particularly, this invention relates to a spindle for use in a spinning or twisting machine for staple fiber spinning as well as for use in drawtwisting machines for processing endless filaments.

Heretofore, spinning and twisting spindles for various types of spinning or twisting machines and drawtwisting machines have been known in which a spindle shaft is mounted by means ofa neck bearing and a foot bearing within a bolster. However, as the neck bearing has usually been rigidly connected to the bolster, vibrations have been transmitted to the spindle rail and to the whole machine, especially at high spindle speeds. As a consequence, a high noise level of the bearing as well as a high loading of the neck bearing and the spindle shaft have been caused.

ln order to overcome these problems, the bolster has been mounted in a flexible or resilient manner to the spindle rail by means of a pressure member surrounding the bolster helically or as a pot. Such a pressure member has usually been supported by the spindle rail directly or via an elastic support member on the underside of the spindle rail. In addition, other elastic support members of similar construction have been positioned between the upper side of the spindle rail and the bolster flange. Arrangements of this type, however, cannot ensure sufficient dampening at high spindle speeds and their life is unsatisfactorily short. Also, elastically mounting the neck bearing in the bolster by means of a rubber or Vulcollan ring or similar devices has not proved satisfactory as these devices inherently cannot yield enough. Such rings are also subject to considerable wear, as they are subject to alternating loads and because the torque to be taken up frequently causes rotation of the rubber rings.

Further, it has been known to mount the neck bearing within a sleeve and to position a sandwich tube between the sleeve and the bolsterabove a dampening spiral member which is placed between the sleeve and bolster. These sandwich tubes usually consist of two concentric metal sleeves with an elastomer layer inbetween. ln this manner, resilient lateral yielding of the neck bearing is made possible. However, the concentric metal sleeves must be manufactured with very high precision in order to ensure precise positioning with the adjacent parts, i.e., with the bolster on one hand and with the inner sleeve on the other hand. Further, as the elastomer layer should not be subject ,to axial load, the metal sleeves must be pressed simultaneously into the bolster and onto the inner sleeve, achievement of which, is very difficult. Still further, resilient materials such as rubber, Vulcolland, etc., to be used in the elastic sandwich layer cannot withstand alternating loads and are subject to excessive wear, and the useful life span of such layers is severely shortened under the influence of oil and fiber preparation fluids. As a consequence, frequent replacement has been necessary. This, of course, implys a complicated disassembling and assembling of the bolsters.

A further disadvantage of the elastic sandwich layer of a sandwich tube, assuming the overall dimensions are maintained, is that if a specific radial flexibility is chosen, the cardanic flexibility is also determined automatically. Thus, the flexibilities cannot be chosen independently and thus cannot, or only unsatisfactorily, be

optimized. As a result, undesirably high bearing loads occur. Furthermore, the use of the elastomer sandwich layer results in temperature differences of the elastic material of the sandwich layer from spindle to spindle, due to unavoidable differences of imbalance caused, e.g. by different tube excentricities and varying unbalance of the yarn packages being built. Thus, the critical rotational speeds differ from spindle to spindle and vary over the build up of the yarn package. The resulting enlargement of the overall range of possible critical spindle speeds of the totality of spindles of a machine correspondingly reduces the range of noncritical spindle speeds available for operation. The range of application of the machine, thus, is impaired undesirably due to the behavior of the rubber sandwich layer.

It is also noted that differing dampening properties result from the temperature differences mentioned of the elastomer layers. This is a disadvantage which results in differing operating characteristics of the spindles. As resonances also occur on spindles rotating at noncritical speeds, which resonances are caused by the impulses of the drive tape joint and by the variations of yarn tension, i.e., to the rotation of the spindle itself, vibrations are superimposed. This adds further yarn tensions to the yarn tension already present and thus increases the danger of end breakages.

Also, the resulting force transmitted from the spindle drive tape to the spindle whorl is not compensated for by the sandwich tube. Thus, the inner sleeve is inclined with respect to the bolster and the damping element arranged between the bolster and the inner sleeve, e.g. the dampening spiral, is unilaterally deformed. As a result, the dampening effect of the dampening element becomes direction-dependent and the geometrical axis of rotation of the spindle is forced into a path in a roughly elliptical cone surface with the obvious disadvantages resulting from this.

Accordingly, it is an object of the invention to reduce the bearing loads for a spindle used in a spinning or twisting machine to a minimum.

It is another object of the invention to achieve conditions under which the axis, about which the rotating parts of a spindle including a yarn package actually rotates, can approach the axis of inertia through the center of gravity as closely as possible.

It is another object of the invention to elastically mount a spindle within a bolster in a manner to avoid wear on the elastic mounting members.

It is another object of the invention to have a spindle mounting withstand large eccentricities.

It is another object of the invention to reduce noise levels and to transmit minimal vibrations to the machine in which a spindle is mounted.

It is another object of the invention to extend the useful life of spindles and their mountings.

It is another object of the invention to provide a universal range of applicability of a spindle with respect to yarn package weight as well as to operational spindle speeds.

Briefly, the invention provides an arrangement for mounting a spindle in a bolster which can be rigidly secured to a spindle rail. The arrangement includes the combination of a rigid sleeve in which a neck bearing and a foot bearing are mounted to receive and rotatably support a spindle shaft, a radially symmetrical dampening element between the sleeves and bolster, and a pair of radially symmetrical elastic members which connect opposite ends of the sleeve to the bolster. In addition, the sleeve is supported on the bolster at the lower end in a rigid manner axially thereof.

In one embodiment, in order to provide for a rigid axial connection between the sleeve and bolster, the sleeve is slidably mounted in the bottom of the bolster. In another embodiment, the lower elastic member is connected between the bottom of the sleeve and the bolster so as to rigidly support the sleeve in a vertical plane. In such an embodiment, a spring rod or a helically coiled wire spring is used for the elastic member. Further, in this latter embodiment the upper elastic member is formed as an apertured disc having a spiral slot therein which serves to impart elastic characteristics to the member.

These and other objects and advantages of the invention will become more apparent from the following detailed description and appended claims taken in conjunction with the accompanying drawings in which:

FIG. 1 illustrates a schematic view of a spindle bearing arrangement according to the invention;

FIG. 2 illustrates a schematic view of a modified spindle bearing arrangement according to the invention;

FIG. 3 illustrates a detailed longitudinal section of a further spindle bearing arrangement according to th invention;

FIG. 4 illustrates a cross-sectional view of the upper connecting member of FIG. 3; and

FIG. 5 illustrates an axonometric view of the lower connecting member of FIG. 3.

Referring to FIG. 1, a spindle shaft 1 on which a yarn package 2 is wound is rotatably supported by two bearings 3 and 4 axially and radially in a rigid inner sleeve 5. The inner sleeve 5 is connected in a radially symmetrically manner via two elastic spring members 6 and 7 of great softness, e.g.springs, in two different planes with a bolster or casing 8 so as to be radially movable. The bolster 8 is, in turn, rigidly fixed to a spindle rail 9. The inner sleeve 5 is also supported on the bottom part 10 of the bolster 8 so as to be rigidly disposed relative to the bolster 8 in the axial direction while being movable radially. Furthermore,

dampening elements

11 and 12 which are each radially symmetrical are provided between the sleeve 5 and the side-walls of the bolster 8.

In operation, the spindle dynamically behaves as follows.

Of the axes shown in FIG. 1, one represents the free axis A, about which the spindle would rotate in the absence of bearing forces acting thereon. This axis A is identical with one of the main axes of inertia through the center of gravity S. The outer forces necessarily acting on the spindle, such as bearing guiding forces, yarn tension, etc., influence the spindle in such manner that all rotating elements of the spindle including the yarn package 2 rotate not about this free axis A but about another axis, namely an axis of actual rotation B at an angular velocity W. The free axis A of the rotating spindle including the yarn package generally also does not coincide with the axis C determined by the geometry of the guiding elements (i.e., the bearings 3 and 4). This is prevented by imprecisions of the package tube seat, deformed package tubes and irregular yarn package formation, etc. In order to keep the bearing loads to a minimum under these conditions, i.e. in order to permit rotation of the yarn package 2 and all other elements of the spindle rotating about the axis of actual rotation B as closely as possible to the free axis -A, the spring constants of the elastic members 6 and 7 are kept as low as possible. That is, the elastic members 6 and 7 are chosen very soft. As, however, at increasing rotational speeds, the mass forces generated by the movable but non-rotating elements (dead masses") increase, their influence on the bearing loads at increasing rotational speeds relatively soon outweighs the spring forces, which are low in any event. Thus, the maximum rotational speed permissible is limited by the magnitude of these mass forces. In order to elevate this limit as high as possible, the inner sleeve 5 must be very light, i.e., with a minimum wall thickness just ensuring the rigidity between the two bearings 3 and 4. If a light metal sleeve is chosen, the mass forces can be reduced further.

Referring to FIG. 2, wherein like parts as above are similarly illustrated, the spindle bearing arrangement which is based on the same principle as the arrangement shown in FIG. 1, has an inner sleeve 13 supported by a friction-free and, thus, wear-free spring rod 14 instead of being supported by a friction-generating surface. The spring rod 14 is soft in the radial direction but very stiff in the axial direction. The dynamic behavior of the arrangement in principle is the same as that described with reference to FIG. I, thus a further description is not believed to be necessary.

Referring to FIG. 3, the bearing arrangement is preferably constructed to cooperate with a bolster or bearing housing 15 which is fixed in known manner via a flange 17 on a spindle rail 16. The bolster 15 is provided with a cylindrical lower part 18 which extends vertically downard, as viewed, and with a bottom 19 containing an opening 20. Between the bolster flange I7 and a cover flange 21, an upper radially symmetrical elastic spring connecting member 22 is fixed along the circumference by means of detachable screws 23. The elastic member 22 has a central bore 24 into which a thin-walled, and thus light, but rigid inner sleeve 25 is pressed in. The sleeve 25 in turn mounts a neck bearing 26 in the upper part which neck bearing 26 is constructed as an anti-friction bearing for rotatably receiving a spindle shaft 27. The lower end of the sleeve 25 has a foot bearing 28 rigidly mounted therein. In addition, a lower elastic connecting member 29 which also is radially symmetrical has an upper vertical end fixed rigidly in the foot bearing 28. The other vertical end of the lower connecting member 29 is rigidly mounted in a support member 30, which is provided with a stud 31 protruding through the larger opening 20, so that the stud 31 can be adjusted and fixed by means of a nut 32 in a certain chosen position. A gasket 33 seals the opening 20 against oil leakage. A dampening spiral 33' is also arranged between the bolster l8 and the inner sleeve 25 in a manner as is known.

The elements which serve to substantially determine the dynamic behavoir of the spindle bearing arrangement are constructed as follows.

The upper elastic spring connecting member 22 is constructed as a metal disc of uniform thickness, the radial elasticity of which is obtained by stamping out one spiral slot 34 (FIG. 4) beginning near the inner. bore 24 and ending near the outer circumference. The elastic properties of the metal disc are thus practically radially symmetrical. Of course, a plurality of spiral slots also can be chosen, if desired. The thickness of the connecting member 22 is determined according to the material chosen (e.g. spiral steel) and, if a certain spring constant for the radial direction is chosen, according to the requirements of rational manufacturing methods (e.g. stamping), to the outside diameter, as well as to the shape of the spiral slot 34 itself. The dimensions of the slotted metal disc also determine the spring constant in the axial direction, which as a rule is considerably smaller than the one in the radial direction, but which in this member is of no consequence. Thus, e.g. for a drawtwisting spindle rotating at a fast speed at about 10,000 r.p.m., with yarn package weights commonly used today of 2-4 kilograms (kg), using corresponding spindle dimensions, the spring constant in the radial direction K is chosen below 30 kilograms per millimeter (kg/mm).

The lower elastic spring connecting member 29 is also of simple construction taking the shape of a helical steel spring. This member- 29 is practically radially symmetrical, i.e., the spring constant in the radial direction does not depend on the direction. The spring constant in the radial direction K can be chosen somewhat lower than that of the upper connecting member 22.

The spring constant in the axial direction, however, must be very high, i.e., the spring rod 29 should be practically rigid in the axial direction in order to carry the weight of the spindle and of the yarn package. For example, for the aforementioned drawtwisting. spindle, the spring constant in the radial direction K should be below kilograms per millimeter (kg/mm) and in the axial direction K above 50 kg/mm, Such steel springs are advantageous insofar as they are resistant to alternating loads if their dimensions are chosen correctly, in which respect they differ favorably from elastomers.

The light, thin-walled, inner sleeve 25 can be made from steel or preferably from light metal. If the weight does not exceed one-tenth to one-fifth of the full yarn package weight, the sleeve weight should meet the requirements with respect to the magnitude of this mass.

The advantages obtained from the spindle bearing arrangement described above are simplicity of construction and, thus, economical manufacturing of the few parts needed, and simplicity of assembly work. Further, the connection of the inner sleeve in a manner which is free of friction and wear and which is elastic in the radial direction serves to increase the life span of all members subject to alternating loads. Further, as no displacement of the spindle shaft relative to the bearings can occur due to the radially elastic support of the rigid inner sleeve, small bearing clearances and, thus, low noise levels and long life of the neck and foot bearings can be realized.

A further advantage is the adjustability of the position of the support member and, thus, of the lower connecting member which permits full compensation of an inclination of the inner sleeve caused by the driving tape tension. In addition, large eccentricities can be tolerated along with higher rotational speeds and higher yarn package weights. Also, another advantage resides in that larger deviations of the package tube seats from concentricity can be tolerated.

Use of the inventive spindle bearing arrangement also allows the bolster to be fixed rigidly to the spindle rail. The advantages resulting from this are that the spindle can be plumbed easily and that any displacement with respect to the spindle rail in the radial as well as in the axial'direction is excluded. The bolster, thus,

cannot be inclined under the influence of impacts from the outside. Further, since the bolster is rigidly fixed to the spindle rail, its position cannot-be altered by contaminations during operation. This, according to experience, is a considerable advantage. v

The inventive arrangement furthermore presents the advantage that no replacement parts are needed, the

support seats of which could cause fitting rust formation. As a further advantage, owing to the fixed mounting of the bolster on the spindle rail, assembly of a fixed arrangement of a spindle brake can be effected easily.

Another advantage is that the soft connection via the elastic members results in a low critical speed of rotation. This is important, as, in this case, smaller bearing loads are generated and, as the practicable range of spindle speeds is larger with respect to the critical speed, so that at low yarn package weights at which inherently the critical speed is higher, the critical speed can still be maintained at a low level. Reduction of the bearing loads to a minimum also proves advantageous in that a lighter inner sleeve can be used to ensure the rigidity needed for keeping the bearings mutually coaxial and the small mass of the inner sleeve cannot reduce the upper admissible limit of the spindle speed noticeably.

What is claimed is:

1. In combination a spindle rail;

at least one bolster rigidly fixed on said spindle rail;

a spindle shaft;

a rigid sleeve disposed about said shaft and rigidly supported on said bolster in an axial direction of said sleeve;

a neck bearing rotatably mounting said shaft in said sleeve;

a foot bearing rotatably mounting a lower portion of said shaft in said sleeve;

a radially symmetrical dampening element disposed between said sleeve and said bolster;

a first radially symmetrical elastic spring member connecting said sleeve to said bolster to one side of said dampening element, said first elastic spring member being an apertured disc having a continuous outer circumferential surface, a continuous inner circumferential surface and a spiral slot between said surfaces; and

a second radially symmetrical elastic spring member connecting said sleeve to said bolster on an opposite side of said dampening element.

2. The combination as set forth in claim 1 wherein said first elastic spring member has a spring constant in a radial direction lower than 30 kilogram per millimeter. I

3. The combination as set forth in claim 1 wherein said second elastic spring member has a spring constant- 6. The combination as set forth in claim wherein said spindle shaft is disposed in a vertical plane with said spring rod disposed therebelow.

7. The combination as set forth in claim 1 wherein said second elastic member is a helically coiled spring wire having one end fixed to said foot bearing and an opposite end fixed to said bolster; said spring wire generating radially uniform spring forces.

8. The combination as set forth in claim 1 wherein said second elastic member is adjustable laterally of said bolster.

9. The combination as set forth in claim 1 wherein said first and second spring members are made of metal.

10. In combination a bolster;

a spindle shaft;

a first radially symmetrical elastic spring member connecting said sleeve to said bolster above said dampening element, said first elastic spring memher being an apertured disc having a continuous outer circumferential surface, a continuous inner circumferential surface and a spiral slot between said surfaces; and

a second radially symmetrical elastic spring member connecting said sleeve to said bolster below said dampening element.

11. The combination as set forth in claim 10 wherein said second elastic spring member supports said sleeve on said bolster in a rigid manner axially of said shaft.

12. The combination as set forth in claim 10 wherein said first elastic spring member has a spring constant in a radial direction lower than 30 kilograms per millimeter and said second elastic spring member has a spring constant in a radial direction lower than l5 kilograms per millimeter.

13. In combination a bolster;

a rigid sleeve concentrically disposed within said bolster',

a radial symmetricalv dampening'element disposed between said sleeve and said bolster;

a first radially symmetrical elastic spring member connecting said sleeve to said bolster above said dampening element, said first elastic spring member being an apertured disc having a continuous outer circumferential surface, a continuous inner circumferential surface and a spiral slot between said surfaces; and

a second radially symmetrical elastic spring member connecting said sleeve to said bolster below said dampening element 14. The combination as set forth in claim 13 wherein said second elastic spring member is a radially movable spring rod having one end fixed to said sleeve and an opposite end fixed to said bolster, said spring rod being rigid axially of said sleeve to rigidly support said sleeve on said bolster in said axial direction of said sleeve.

15. The combination as set forth in claim 13 wherein said second elastic member is a helically coiled spring wire having one end fixed to said sleeve and an opposite end fixed to said bolster, said spring wire generating radially uniform spring forces.

16. The combination as set forth in claim 13 which further includes a foot bearing within said sleeve at a lower end and a neck bearing within said sleeve at an upper end to receive and rotatably support a shaft spindle therein.

Claims

1. In combination a spindle rail; at least one bolster rigidly fixed on said spindle rail; a spindle shaft; a rigid sleeve disposed about said shaft and rigidly supported on said bolster in an axial direction of said sleeve; a neck bearing rotatably mounting said shaft in said sleeve; a foot bearing rotatably mounting a lower portion of said shaft in said sleeve; a radially symmetrical dampening element disposed between said sleeve and said bolster; a first radially symmetrical elastic spring member connecting said sleeve to said bolster to one side of said dampening element, said first elastic spring member being an apertured disc having a continuous outer circumferential surface, a continuous inner circumferential surface and a spiral slot between said surfaces; and a second radially symmetrical elastic spring member connecting said sleeve to said bolster on an opposite side of said dampening element.

2. The combination as set forth in claim 1 wherein said first elastic spring member has a spring constant in a radial direction lower than 30 kilogram per millimeter.

3. The combination as set forth in claim 1 wherein said second elastic spring member has a spring constant in a radial direction lower than 15 kilograms per millimeter.

4. The combination as set forth in claim 1 wherein said dampening element is a dampening spiral member.

5. The combination as set forth in claim 1 wherein said second elastic spring member is a radially movable spring rod having one end fixed to said foot bearing and an opposite end fixed to said bolster, said spring rod being rigid axially of said shaft to rigidly support said sleeve on said bolster in said axial direction of said sleeve.

6. The combination as set forth in claim 5 wherein said spindle shaft is disposed in a vertical plane with said spring rod disposed therebelow.

7. The combination as set forth in claim 1 wherein said second elastic member is a helically coiled spring wire having one end fixed to said foot bearing and an opposite end fixed to said bolster, said spring wire generating radially uniform spring forces.

10. In combination a bolster; a spindle shaft; a rigid sleeve disposed about said shaft and rigidly supported on said bolster in an axial direction of said sleeve; a radially symmetrical dampening element disposed between said sleeve and said bolster; a first radially symmetrical elastic spring member connecting said sleeve to said bolster above said dampening element, said first elastic spring member being an apertured disc having a continuous outer circumferential surface, a continuous inner circumferential surface and a spiral slot between said surfaces; and a second radially symmetrical elastic spring member connecting said sleeve to said bolster below said dampening element.

12. The combination as set forth in claim 10 wherein said first elastic spring member has a spring constant in a radial direction lower than 30 kilograms per millimeter and said second elastic spring member has a spring constant in a radial direction lower than 15 kilograms per millimeter.

13. In combination a bolster; a rigid sleeve concentrically disposed within said bolster; a radial symmetrical dampening element disposed between sAid sleeve and said bolster; a first radially symmetrical elastic spring member connecting said sleeve to said bolster above said dampening element, said first elastic spring member being an apertured disc having a continuous outer circumferential surface, a continuous inner circumferential surface and a spiral slot between said surfaces; and a second radially symmetrical elastic spring member connecting said sleeve to said bolster below said dampening element.

14. The combination as set forth in claim 13 wherein said second elastic spring member is a radially movable spring rod having one end fixed to said sleeve and an opposite end fixed to said bolster, said spring rod being rigid axially of said sleeve to rigidly support said sleeve on said bolster in said axial direction of said sleeve.