GB2071166A - Driving drafting rollers - Google Patents

Abstract

In a textile yarn spinning machine the number of spinning stations can be increased by providing two sets of three lower drafting rollers 4, 5, 6; 11, 12, 13 each of which terminates at an intermediate position along the machine. The ends of each set of the lower drafting rollers are interconnected by drive transmission means each of which is driven by drive means which are interconnected by a driving belt 21 extending along the machine and drivingly contacts a plurality of yarn take-up spindles. <IMAGE>

Description

SPECIFICATION Driving arrangement for yarn spinning machines The invention relates to textile yarn spinning machines of the type comprising a plurality of juxtaposed spinning stations, each comprising of a drafting unit and yarn take-up spindle.

More particularly, the invention is concerned with an improved driving apparatus for spinning machines of the above type.

From an economic aspect, it is desirable to increase the production capacity of a machine by providing as large a number of spinning stations as possible. However, there are mechanical limitations imposed upon the designer who seeks to accommodate an increase in the number of spinning stations by lengthening the machine.

Normally, the lower rollers of the drafting units are interconnected at one end by a gear train which is driven by a motor. These rollers extend in a continuous length along the machine from one end to the other so as to serve each of the drafting units and are supported in bearings at spaced intervals. With this arrangement a problem would arise upon lengthening the machine because of the occurrence of excessive twisting of the rollers when a driving torque is applied to them. The degree of twist exhibited by these rollers varies from a maximum value at the driven end of these rollers to a minimum value at their free ends.

Obviously this problem becomes more acute as the lengths of the rollers are increased and the angle of twist will exceed the acceptable limit for satisfactory operation. When the machine is operating, this twisting in the rollers will produce faults in the yarn, which is particularly evident when the machine is stopped. At this time the rollers will tend to untwist with the result that breakages in the yarn, particularly at the free ends of the rollers, could occur.

According to the invention there is provided a textile yarn spinning machine having a plurality of juxtaposed fibre drafting units comprising a first set of three lower rollers extending from one end of the machine and terminating at an intermediate position along the machine and serving some of the drafting units, and a second set of three lower rollers extending from the other end of the machine and terminating at an intermediate position along the machine and serving the remainder of the drafting units, a first drive transmission means interconnecting each of the lower rollers of the first set at the said one end and a second drive transmission means interconnecting each of the rollers of the second set at the said other end, first drive means for driving the first drive transmission means and second drive means for driving the second transmission means, and a driving belt interconnecting the first and second drive to transmit a drive therebetween.

Preferably the driving belt extends along the machine and contacts a plurality of yarn take-up spindles to impart rotation thereto.

The drawing illustrates, by way of example, a schematic driving arrangement for a spinning machine according to a preferred embodiment of the invention.

The invention is described as incorporated in a ringframe type of spinning machine, but it is applicable to other types of spinning machine such as, for example, roving frames.

Referring to the drawing the ringframe is provided with a plurality of juxtaposed spinning stations 1 each of which comprises a drafting unit 2 and a yarn take-up spindle 3. Each of the spindles 3 is provided with a ring and traveller assembly (not shown) for twisting and distributing the yarn on the spindle.

The ringframe is divided longitudinally so as to produce two sections each containing an equal number of drafting units 2. Each drafting unit 2 contained in the left hand section, as viewed in the drawing, has a back lower roller 4, a middle lower roller 5, and a front lower roller 6. Individual top rollers 7, 8 and 9 co-operate respectively with the three lower rollers 4, 5 and 6. The top rollers 7, 8 and 9 are normally mounted on a common arm which is cantilever mounted and weighed so as to press the top rollers into contact with the lower rollers. Each of the lower rollers 4, 5 and 6 is supported at its free end by a bearing supported in a common bearing unit 10 and also by bearings (not shown) at spaced intervals along the machine.

Each drafting unit 2 in the right hand section, as viewed in the drawing, has a back lower roller 11, a middle lower roller 12, and a front lower roller 13, which co-operate with respective top rollers 7, 8 and 9 in the manner previously described in relation to the left hand section. Each of the lower rollers 11, 12 and 13 is supported at its free end by a bearing supported in a common bearing unit 14 and also by bearings (not shown) at spaced intervals along the machine.

In operation, a roving is supplied to each of the drafting units 2 and passess successively through the back, middle and front pair of rollers, each pair rotating at a higher speed than the preceding pair so as to attenuate the material.

Associated with each drafting unit 2 is one of the spindles 3 upon which the yarn delivered from the drafting units is distributed by a ring and traveller assembly (not shown) in the conventional manner.

The drive for all of the drafting units 2 and the spindles 3 is derived from a main motor 1 5. A drive pulley 1 6 is mounted on an output shaft of the motor 1 5 and imparts rotation to a driven pulley 1 7 by means of a driving belt 1 8. The driven pulley 17 is mounted on one end of a countershaft 1 9 which also supports a further drive pulley 20. A spindle driving belt 21 partially encircles the drive pulley 20 so as to be driven thereby. The driving belt 21 extends along the whole length of the machine and rotates each of the spindles 3 by technical contact with a pulley 22 provided on each of the spindles 3.At the end of machine remote from the motor 15, the driving belt 21 partially encircles a driven pulley 23 mounted on one end of a countershaft 24.

The drive to the right hand section of drafting units 2 is effected by a bevel gearwheel 25 mounted on the countershaft 1 9 which meshes with a bevel gearwheel 26 supported on the end of the front lower roller 1 3. Each of the lower rollers 11, 12 and 13 carries a gearwheel, respectively indicated as 27, 28 and 29. A pair of intermediate gearwheels 31 is interposed between the gearwheels 27 and 28 of the back and middle lower rollers, and a further pair of intermediate gearwheels 32 is interposed between the gearwheels 28 and 29 of the middle and front rollers.

Similarly, the drive to the left hand section of drafting units 2 is effected by a bevel gearwheel 33 on the one end of the countershaft 24 which meshes with a further bevel gearwheel 34 mounted on the end of the front lower roller 6.

Each of the lower rollers 4, 5 and 6 carries a gearwheel, respectively indicated as 35, 36 and 37. A pair of intermediate gearwheels 39 is interposed between the gearwheels 35 and 36 of the back and middle lower rollers and a pair of intermediate gear wheels 40 is interposed between the middle and front lower rollers.

It will be appreciated that each pair of bevel wheels 25, 26 and 33, 34 is a simplified representation of a twist gearbox. This gearbox will, in practice, include a twist change gearwheel which can be replaced by another gearwheel when it is desired to change the twist in the yarn.

The driving arrangement of this invention permits the lengthening of a spinning machine without incurring the problem of excessive twisting of the lower drafting rollers. Because these lower rollers extend only to a mid-point of the machine, the machine length can be increased up to twice the length of conventional machines.

Therefore, a larger number of spindles can now be accommodated, with a consequent increase in the productive capacity of the machine.

Claims (4)

1. A textile yarn spinning machine having a plurality of juxtaposed fibre drafting units comprising a first set of three lower rollers extending from one end of the machine and serving some of the drafting units, and a second set of three lower rollers extending from the other end of the machine and terminating at an intermediate position along the machine and serving the remainder of the drafting units, a first drive transmission means interconnecting each of the lower rollers of the first set at the same one end and a second drive transmission means interconnecting each of the rollers of the second set at the said other end, first drive means for driving the first drive transmission means and second drive means for driving the second drive transmission means, and a driving belt interconnecting the first and second drive transmission means to transmit a drive therebetween.

2. A textile yarn spinning machine according to claim 1, wherein the driving belt extends along the machine and contacts a plurality of yarn take-up spindles to impart rotation thereto.

3. A textile yarn spinning machine according to claims 1 or 2, wherein the first and second drive means each includes a twist gearbox comprising a twist change gearwheel.

4. A textile yarn spinning machine according to claim 3, wherein the drive to the first and second drive means is derived from a single motor.