FIELD OF THE INVENTION
The present invention relates to the technical field of textile spinning machinery. Particularly, the invention relates to a spindle of textile ring spinning machine.
BACKGROUND OF THE INVENTION
The ring spinning machine comprises a plurality of spindles mounted on respective spindle rails on both the rows of the machine frame, for rotatably winding the yarn, which is being drafted and twisted, upon a cop/tube which is mounted on to the spindle. The spindle used in a ring spinning machine comprises a spindle blade assembled in the upper part of the spindle which is rotatably supported in the bottom part and driven by the drive system of the ring spinning machine. The spindle blade is rotatably supported by a neck bearing and a foot bearing. The neck bearing is positioned in a tube-like inner housing which is pressed inside the bottom portion of outer housing. The bottom portion of the outer housing is closed and so designed such that it can be fitted on the spindle rail and vertically aligned. The neck bearing cage comprises plurality of pockets which acts as the housings for the plurality of needle rollers.
In existing ring spinning spindles, neck bearing needle roller cages are manufactured as two types. The first type is without retainers for needle rollers in the cage. The second type is with retainers / retaining leaf for needle rollers in the cage. The first type without retainer is usually disadvantageous because the assembly process is very difficult and time consuming. The latter type of neck bearing needle roller cages with retainers are considered

advantageous, considering the ease in assembling process.
In existing neck bearing needle roller cages, there are four retainers provided in a cage pocket for holding each needle roller. Each cage pocket contains
> two retainers at top and two retainers at bottom opposite to each other in a same plane for holding needle rollers. In this type of retainers, there are manufacturing difficulties such as short mold formation, ie. incomplete filling of mold cavity which results in the production of a defective part, reduced tool life, difficult to maintain the geometrical & dimensional specifications, due to
i lesser component size and low weight and multiple retainer leaf (say 28 retainers) for single neck bearing cage, to accommodate needle rollers.
There exists a need to overcome the above mentioned disadvantages, to which the present invention provides an improved solution.
OBJECTS OF THE INVENTION
The main object of the present invention is to provide an improved spindle bearing in textile ring spinning machines.
It is another object of the present invention to provide an improved neck bearing cage which is easy to manufacture and simple in structure.
SUMMARY OF THE INVENTION
According to the present invention, in ring spinning spindles, the neck bearing cage is provided with only two retainers / retaining leaf for each pocket of the needle roller cage. The said two retainers are provided in a diagonally

opposite manner in different planes at each pocket of the neck bearing cage. According to the present invention, the number of retainers in each pocket of the neck bearing cage is reduced to half the number of actual.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS
Figures 1 & 1a illustrates the isometric views of the spindle assembly and spindle bearing showing neck bearing cage respectively, mounted in the spindle of ring spinning machine.
Figure 2 illustrates an isometric view of the neck bearing assembly without needle rollers in accordance with the prior art.
Figure 2a illustrates an isometric view of the neck bearing assembly with needle rollers in accordance with the prior art.
Figure 3 illustrates an isometric view of the neck bearing assembly without needle rollers according to the present invention.
Figure 3a illustrates an isometric view of the neck bearing assembly with needle rollers according to the present invention.
DETAILED DESCRIPTION OF THE INVENTION
Referring to figures 1 & 1a, the ring spinning spindle (1) is shown with the top part comprising a neck bearing cage (2) which is housed in the spindle assembly.

As shown in figures 2 & 2a, the existing spindles in ring spinning machines are provided with a neck bearing cage (2) with a plurality of pockets (3). The pockets (3) of the neck bearing cage (2) are provided with a plurality of retainers / retaining leaf (4) for holding a plurality of needle rollers (5). In existing arrangement, there are four retainers (4) provided for a cage pocket (3) for holding each needle roller (5). Each cage pocket (3) contains two retainers at top (4a) and two retainers at bottom (4b) opposite to each other in a same plane, for holding the needle rollers (5). In this type of retainers (4), there are manufacturing difficulties such as short mold formation, ie. incomplete filling of mold cavity which results in the production of defective part, reduced tool life, difficult to maintain the geometrical & dimensional specifications, due to lesser component size and low weight and multiple retainer leaf (say 28 retainers) for single neck bearing cage (2), to accommodate needle rollers (5).
According to the invention as illustrated in figures 3 & 3a, in ring spinning spindles, the neck bearing cage (2) is provided with only two retainers / retaining leaf (44) for each pocket (3) of the needle roller (5) / neck bearing cage (2). The said two retainers (44) are provided in a diagonally opposite manner in different planes at each pocket (3) of the neck bearing cage (2). According to the present invention, the number of retainers (44) in each pocket (3) of the neck bearing cage (2) is reduced, preferably 14 retainers (44) per neck bearing cage (2) with 7 pockets. Advantageously, the pockets can be increased or decreased based on the spindle type and likewise retainers can also be increased or decreased to suit the respective number of pockets.
According to an embodiment of the present invention, the retainers are made of polymer or composite material or lightweight material. The retainer

positioning according to the present invention is easy to manufacture and the needle roller assembly process is also made easier.
Advantageously, the proper holding of needle rollers is ensured by the retainer's position. The needle rollers are gently held by the retainers without falling and also without making any hindrance to the needle rollers while rotating. Advantageously, the retainers are placed diagonally opposite in a pocket to hold the needle roller. The minimum width of a retaining element is at least 1/5 times of the total length of the rolling element / needle roller. The maximum width of a retaining element is maintained from 2/5 to 3/5 times of the total length of the rolling element / needle roller.
The main advantage of the present invention lies in the fact that, due to reduced number of retainers, resistance / rolling contact friction offered by the retainers will be minimized. There are also advantages in terms of reduced power consumption or the spindle rotation speed will be increased, compared to the conventional retainer arrangement. The manufacturing is done by injection molding and the manufacturing is made easy as there are less number of retainers per pocket and the complexity of the tool and die used for molding are greatly minimized. The molding defects like short fill (short mold / incomplete mold filling) are avoided. The total weight of the spindle bearing assembly is also reduced. The assembly time is also significantly reduced, when compared with conventional arrangement.
Advantageously, the bearing cage according to the present invention is not limited to ring spinning machines. The improved retainer along with bearing cage according to present invention can also be applied to all textile machines including Blow room, Carding, Comber, Lap former, Draw frame,

Speed frame, Air jet spinning, Winding machines, etc. Also, the bearing is not limited to needle bearing and it includes all types of bearings used in textile machines.
In view of the present disclosure which describes the present invention, all changes, modifications and variations within the meaning and range of equivalency are considered within the scope and spirit of the invention. It is to be understood that the aspects and embodiment of the disclosure described above may be used in any combination with each other. Several of the aspects and embodiment may be combined together to form a further embodiment of the disclosure.