Title:
Thread delivery device for textile machines
United States Patent 3901052


Abstract:
A thread delivery device including a shaft having a thread storage drum supported thereon. The shaft has two belt engaging pulleys mounted thereon and disposed in engagement with two driving belts which travel at different speeds. One of the pulleys is always nonrotatably connected to the shaft and functions as a driving pulley, same being engaged with one of the driving belts. The other pulley is freely rotatably supported on the shaft by means of a bearing, and is disposed in driving engagement with the other belt. The two pulleys can be readily removed from the shaft and remounted thereon in the reverse order so that the one pulley is still nonrotatably connected to the shaft and functions as a driving pulley, but is instead disposed in driving engagement with the other driving belt. This removal and remounting of the pulleys in reverse order thus permits the speed of the drum to be easily varied.



Inventors:
JACOBSSON KURT ARNE GUNNAR
Application Number:
05/462628
Publication Date:
08/26/1975
Filing Date:
04/22/1974
Assignee:
AKTIEBOLAGET IRO
Primary Class:
Other Classes:
66/132R, 66/132T
International Classes:
B65H51/22; D04B15/48; (IPC1-7): D04B15/48
Field of Search:
66/125R,132R,132T 242
View Patent Images:
US Patent References:
2539527Yarn feeding device1951-01-30Pierre
2432518Speed indicator for warp knitting machines1947-12-16Esivteman



Primary Examiner:
Stein, Mervin
Assistant Examiner:
Hawkins, Steven
Attorney, Agent or Firm:
Woodhams, Blanchard And Flynn
Claims:
What we claim is

1. A thread delivery device for textile machines, particularly knitting machines, comprising a shaft, a component interconnected to said shaft so as to be rotated thereby, at least two belt pulleys coaxially mounted on said shaft, and two driving belts travelling at different speeds, one of the pulleys always being non-rotatably connected to the shaft and the other pulley freely rotatably mounted on the shaft, the improvement wherein the one pulley is always nonrotatably connected to the shaft and serves only as a driving pulley (19 or 119), while the other pulley is mounted on the shaft be a ball bearing and is thereby always a freely rotating pulley, the two pulleys being freely axially removed from the shaft and interchangeably mounted thereon, and the driving pulley being replaceable by one of a plurality of interchangeable driving pulleys of variable diameter.

2. A thread delivery device as claimed in claim 1, wherein the ball bearing of the freely rotating pulley is mounted on a hub rigidly connected to the driving pulley.

3. A thread delivery device as claimed in claim 1, wherein each driving belt is driven by a driving wheel whose effective diameter can be adjusted to vary the travelling speed of the belt.

4. A thread delivery device as claimed in claim 1, wherein the two pulleys are axially retained on the shaft by a detachable locking nut.

5. In a thread delivery device for a textile machine, particularly a knitting machine, comprising a shaft, a thread storage drum mounted on said shaft at least two belt pulleys coaxially mounted on said shaft, and two driving belts traveling at different speeds, one of said pulleys always being nonrotatably connected to the shaft and disposed in engagement with one of the belts, and the other pulley being freely rotatably mounted on the shaft and disposed in engagement with the other belt, the improvement wherein said one pulley is always nonrotatably connected to the shaft and serves only as a driving pulley while the other pulley is mounted on the shaft by a bearing and is always a freely rotating pulley, the two pulleys being freely axially removable from the shaft and remountable thereon in reverse order so that the one pulley can be disposed in driving engagement with said other belt.

6. A device according to claim 5, wherein said pair of pulleys are mounted closely adjacent one another, said one pulley having an annular hub disposed in surrounding relationship to said shaft and projecting axially outwardly from one end of said one pulley, and said other pulley being disposed so as to surround said hub and being rotatably supported thereon, whereby said pair of pulleys are thus removable from said shaft as a unit.

7. A device according to claim 5, further including locking nut means engageable with the free end of said shaft for maintaining said pulleys thereon.

8. A device according to claim 5, wherein said pair of pulleys are of different diameters.

Description:
The invention relates to a thread delivery device for textile machines, particularly knitting machines, comprising a component which cooperates on the thread delivery system and can be rotated by means of a shaft on which at least two belt pulleys are coaxially mounted, which pulleys are associated with two driving belts moving at different speeds, one of the pulleys always being non-rotatably connected to the shaft and the other pulley freely rotatably mounted on the shaft.

In the case of a well-known previously used thread delivery device of this type the shaft is supported in a stirrup by means of pivot bearings outside a thread drum entwined with thread. The two pulleys are in turn mounted on the shaft by means of pivot bearings between the arms of the stirrup. Between the two pulleys lies an axially slidable coupling element with front toothing which is non-rotatable on the shaft and can be alternately engaged with the pulleys. Therefore the pulley with which the coupling element engages is non-rotatable relative to the shaft while the other pulley if freely rotatable. Each of the driving belts can be driven at a desired speed since it is guided via a driving pulley whose effective diameter is variable. The thread drum can therefore be selectively rotated at two speeds equal to the travelling speeds of the driving belts.

For example, the production of complicated fabric structures by means of a knitting machine requires different thread delivery speeds in the various systems of the machine. It is often the case that more than two different thread delivery speeds are required at the same time when a plurality of thread delivery devices are arranged on the knitting machine. For this purpose the driving shaft in another embodiment of the previously known thread delivery device is lengthened so that it projects freely upwardly out of the stirrup. Another pulley is mounted by means of a pivot bearing on the protruding section of the shaft. Mounted above this other pulley is a second axially slidable coupling element with front toothing which can engage with this pulley. Also a driving belt which can be driven at a desired speed is associated with this other pulley. When three or more thread delivery devices of this type are provided on a machine, three different thread delivery speeds may therefore be obtained simultaneously. However, this is usually still insufficient and moreover calls for a large number of components (an extra driving belt, an additional driving pulley with variable diameter, several more sheave pulleys, etc.) and consequently a large amount of space is required.

There is another known thread delivery device (German Offenlegungsschrift 2,130,697) which is provided with three drivng belts travelling at different speeds. Each thread delivery device is adjustably mounted on a guide rod transversely to the direction of travel of the driving belts. The thread drum can be selectively engaged with each of the belts. When a plurality of these thread delivery devices are arranged on a machine, three different delivery speeds are also possible simultaneously which, as mentioned earlier, is often insufficient, on the one hand, and as in the case of the previously used delivery device described above, requires a large number of components and consequently a great amount of space, on the other hand. Moreover, this solution involves a great deal of work in conversion or adaptation because the delivery devices have to be loosened, adjusted and then secured again.

The problem underlying the invention is to provide a thread delivery device of the type described at the beginning of the specification which on account of the small number of components enables a space-saving arrangement to be provided on the machine as well as permitting almost any desired number of thread delivery speeds to be provided simultaneously in a simple manner.

This problem is solved in accordance with the invention in that the first pulley is always non-rotatably connected to the shaft and serves only as a driving pulley, while the other pulley is mounted on the shaft by means of a pivot ball bearing and is therefore always a freely rotating pulley, in that the two pulleys can be freely axially removed from the shaft and interchangeably mounted thereon, and in that each delivery device is associated with a plurality of interchangeable driving pulleys of variable diameter.

In the thread delivery device according to the invention the driving shaft can be connected to either of the two driving belts by changing the positions of the two pulleys. This exchange may be very rapidly effected by hand since both pulleys can be freely removed from the shaft, preferably after loosening a locking nut, and mounted thereon again in their changed positions. In this case a special connecting element is not required. Since the pulleys can be rapidly and effortlessly removed and remounted, a change of speed caused by replacing one driving pulley with another having a larger or smaller diameter does not present any problem whatsoever.

It is provided in an embodiment of the invention that the ball bearing of the freely rotating pulley is mounted on a hub rigidly connected to the drivng pulley. In this embodiment removal and remounting of the pulleys is even further simplified because the driving pulley and freely rotating pulley are combined to form a unit.

Each driving belt can be driven in a manner known per se by means of a driving wheel, whose effective diameter can be adjusted to vary the travelling speed of the belt. Generally speaking, the necessary great variations in speed between the high-speed systems of groups of systems on the machine and the low-speed systems or groups of systems can be achieved by means of the driving belts travelling at greatly differing speeds, while the necessary small variations in speed between the various systems within each "high-speed group" or "low-speed group" are made possible by the plurality of interchangeable driving pulleys of variable diameter. To avoid confusion the driving pulleys of variable diameter can each be identified by a different colour.

Practical embodiments of the invention are illustrated in the drawings.

FIG. 1 is a diagrammatic plan view of the arrangement of delivery devices according to the invention on a circular knitting machine,

FIG. 2 is a side elevation of a single thread delivery device according to the invention,

FIG. 3 is a vertical partial section through the belt pulley arrangement on a delivery device according to the invention,

FIG. 4 is a section, corresponding to FIG. 3, through a modified embodiment,

FIG. 5 is a side elevation of another individual thread delivery device according to the invention, and

FIG. 6 is a plan view of the thread delivery device shown in FIG. 5.

The diagrammatic plan view in FIG. 1 shows the driving elements of a number of delivery devices 1 which are arranged around the circumference of a ring support (not shown) above a conventional circular knitting machines having twelve systems A-L. As can be seen in the drawing, each delivery device 1 comprises two pulleys, each of which is connected with one of two driving belts 2, 3. The belts are driven by driving wheels 4, 5, respectively, whose diameter can be adjusted in the known manner to obtain different travelling speeds. A "driving circuit" of this special form is used e.g. when knitting articles with the so-called "Milano Rib" weave. In a certain brand and type of knitting machine, the thread delivery speed is in this case intended to be 147 metres/min in system A, 46 metres/min in system B, 64 metres/min in system C, 147 metres/min again in system D, etc. The two driving belts 2, 3 always travel at different speeds, the first belt (in the drawing, belt 3) being used as a high-speed belt and the second (in the drawing, belt 2) as a low-speed belt. In FIG. 1 reference numeral 6 designates several sheave or return pulleys which enable the belt tension to be adjusted and the loops to be formed around the driving wheels 4, 5.

A single thread delivery device 1 is illustrated in FIG. 2. It comprises a thread drum 7 rotatably mounted in a housing 8 which can be clamped by means of a clamping device 9 to the ring carrier of a knitting or other textile machine. The thread F runs off a storage spool (not shown), and passes through a preliminary brake 10, a disc brake 11 and a thread guide 12 so as to be wound tangentially on to the thread drum 7 to form a thread supply V. A tilted thread feed plate 13 displaces the thread supply V axially along the drum surface. The thread F' is withdrawn over the top through a brake ring 14 and a pair of eyelets 15. A stop motion 16 is located between the withdrawal eyelets 15. During withdrawal the thread F' usually comes into contact with the side of a hook 17 which restricts the withdrawal speed to being the same as the wind-on speed and therefore enforces a positive thread delivery.

The thread drum 7 is supported on a shaft 18 which is rotatably mounted in the housing 8 and projects freely upwardly out of the latter. Slidably fitted on to the protruding section of the shaft 18 are two belt pulleys 19 and 20 which can be freely removed at the top after loosening a locking nut 21 screwed on to the shaft 18. Each of the pulleys is encircled by a belt 2 or 3, in which case holes 2a and 3a can be provided in the belts and pins 19a on one of the pulleys for better engagement.

Details of the pulley arrangement are shown in FIG. 3. It can be seen that the pulley 19, which is shown in FIG. 3 without the pins 19a for the sake of simplicity, is non-rotatably mounted on the shaft 18. It therefore forms a driving pulley which transmits the driving power from the belt 2 to the shaft 18. The pulley 20 is mounted on a ball bearing 22 which is in turn mounted on a bearing bush 23 rigidly connected to the shaft 18. A spacer is shown at 24.

FIG. 3 shows that in the illustrated arrangement of components the drive of the shaft 18 and therefore of the thread drum 7 is derived from the driving belt 2 while the belt 3 only rotates the free pulley 20 about the shaft 18. It is easily possible for the locking nut 21 to be unscrewed, the two pulleys 19 and 20 removed from the top of the arrangement and interchangeably remounted. The driving pulley 19 is then enclosed by the driving belt 3 while the belt 2 is connected to the freely rotating pulley 20. The adjustment of belt tension which is necessary in this case is ensured by the pulley arrangement 6 (FIG. 1). In the latter case the shaft 18 and thread drum 7 are driven by the belt 3 while the belt 2 causes the free pulley 20 to rotate.

Each delivery device 1 is associated with a plurality of driving pulleys 19 of variable diameter. For example, in FIG. 1 driving pulleys of a "normal diameter" are indicated by numeral 19 while driving pulleys of a larger diameter which can easily be used instead of the driving pulleys 19 are designated by numeral 19'. It can also be seen from FIG. 1, through the broken or continuous circumferential lines of the freely rotating pulley 20, that the pulley 20 can be mounted either above or below the driving pulley 19 or 19', as has been previously described.

It can also be seen in FIG. 1 that the driving speed in each system or each group of systems can be different so that the machine can be advantageously adapted to suit a great variety of weaves or fabrics. In this special case the necessary great difference in speed between the high-speed systems A,D,G,J, on the one hand, and the low-speed systems B,C,E,F,H,I,K,L, on the other hand, is obtained by means of the drive of the high-speed belt 3 and the low-speed belt 2, respectively, whereas the small difference in speed between the various low-speed systems B and C, E and F, H and I, K and L, is achieved by using the driving pulley of "normal diameter" or pulley of larger diameter as the effective driving pulley on the respective thread delivery devices.

The illustration in FIG. 4 is similar in many respects to that in FIG. 3. As the same reference numerals are used, further description would be superfluous. One different feature from FIG. 3 is that a driving pulley 119 is used, comprising a hub 119a which is integral therewith or rigidly connected thereto, the ball bearing 22 of the freely rotating pulley 20 being mounted on this hub. The spacer 119b can also be integral with the driving pulley 119. This embodiment has the advantage that the two pulleys 119,20 can be removed as a unit from the top of the shaft 18.

The other belt-driven thread delivery device of the invention, which is shown in FIGS. 5 and 6, serves particularly for the positive delivery of elastic threads, e.g. of the Lycra type. Reference numeral 25 designates the housing of the thread delivery device which can be clamped to a ring carrier (not shown) of a knitting or other textile machine by means of a clamping device 26 of the same type as that clamping the delivery device shown in FIG. 2. One end of a shaft 27 of a roller 28 is rotatably mounted in the housing 25 and its other end in the retaining arm 29 extending down from the housing. The thread storage drum 30 is slidably fitted on a cylinder 31. The lower end of the arm 29 comprises two parallel passages 32,33 through which two guide rods 34,35, which are connected to the lower end of the cylinder 31 transversely to the longitudinal direction thereof, can easily slide and therefore enable the cylinder to move radially to the roller 28. The holder arm 29 and the cylinder 31 are also connected at their lower ends by means of a tension spring 36 which constantly presses the thread storage drum 30 against the roller 28.

The shaft 27 of the roller 28 projects freely upwardly out of the housing 25. On the protruding section of the shaft 27 there is provided a two-pulley arrangement 37,38 which is identical to that shown in FIG. 3 or 4. Just as in the previously described cases, each pulley 37,38 can be driven by the central drive of the machine via a belt 39,40 (e.g. a high-speed belt or a low-speed belt), return pulleys and a driving wheel of variable diameter. The shaft 27 may be driven at a desired rotational speed by adjusting the driving wheels, by selecting from the high or low-speed belt drives and from the available interchangeable pulleys.

If the roller 28 rotates, the thread storage drum 30 also rotates constantly at the same circumferential speed whereupon the thread F' is delivered to the working place of the machine via a stop motion 42 at a desired delivery speed which is equal to the said variable rotational speed. If the thread has been properly wound onto the storage drum, which is a fundamental condition for this method of delivery to function, the same length of thread per unit of time and therefore thread with always the same expansion is constantly delivered to the machine, which cannot be achieved with a conventional thread delivery device. Elastic thread which is delivered in this manner is often combined with a normal thread delivered from a conventional storage spool by means of a conventional thread delivery device and they are fed together into the machine, at least where the machine comprises several systems. In each of these systems the conventional thread delivery device and the thread delivery device shown in FIGS. 5 and 6 are simply arranged in juxtaposition on the same ring carrier of the machine and driven by the same belt.

If the double-pulley arrangement according to the invention comprising interchangeable driving pulleys has been described previously in connection with belt-driven thread delivery devices for the positive delivery of thread to the working place on a machine, the use of the invention is in no way limited to such devices; the invention can in principle be used on any thread delivery devices driven by belts or the like, irrespective of whether the devices are provided with a stationary or rotary thread drum or are intended for positive or intermittent thread delivery.