FORM 2
THE PATENTS ACT, 1970 (39 of 1970)
As amended by the Patents (Amendment) Act, 2005
&
The Patents Rules, 2003
As amended by the Patents (Amendment) Rules, 2016
COMPLETE SPECIFICATION (See section 10 and rule 13)
TITLE OF THE INVENTION
An Integrated Needle Bearing Assembly
APPLICANT
NRB Industrial Bearings Ltd, an Indian company, having its address at 2nd Floor Dhannur, 15 Sir P.M. Road, Fort, Mumbai – 400 001, Maharashtra, India
PREAMBLE TO THE DESCRIPTION
The following specification particularly describes the invention and the manner in which it is to be performed:

FIELD OF THE INVENTION
[001] The invention relates to a needle bearing assembly for a spindle shaft of a machine.
BACKGROUND OF THE INVENTION
[002] There are several machines that are used to cut, grind, shear, or deform metals or other rigid materials. An example of such machines is a drill machine having a spindle placed in a housing and a drill bit mounted on a chuck coupled with the spindle. In operation, the drill bit is placed on a work surface and the spindle is rotated about its axis at a desired speed. As a result, the chuck and the drill bit rotate to achieve the drilling operation. The interaction of the drill bit with the work surface brings axial load acting along the axis of the spindle and rotation of the spindle brings radial load acting in a direction that is radially outward and perpendicular to the spindle axis.
[003] Thus, it is known in the art to use bearings mounted on the spindle to carry the axial load and the radial load. In this regard, radial ball bearings having radial load carrying capacity and axial/ thrust ball bearings having axial load carrying capacity are mounted on the spindle. Performance of these ball bearings plays a vital role in performance of the spindle, and by extension the cutting operation performed by the drill bit. However, usage of multiple bearings increases the cost of the machine and increases the maintenance that the machine requires as well. [004] Radial bearings have a cage defined by an outer ring and an inner ring which are integral part of the ball bearing. Similarly, axial bearings have a cage

defined by a top thrust plate and a bottom thrust plate. The thrust plates of the axial bearings and the inner ring of the radial bearings in particular are prone to wear and tear over a period of time. Moreover, these bearing are provided with one time lubrication. Accordingly, the bearings need to be changed whenever wear and tear is caused. If not changed timely, this wear and tear transmits to the spindle of the machine which can damage the spindle and render it useless. Accordingly, the spindle may also need to be changed.
[005] Therefore, there is a need to have a bearing which can address the aforementioned problems.
SUMMARY OF THE INVENTION
[006] The present invention discloses an integrated needle bearing assembly. The integrated needle bearing assembly comprises: an integrated needle bearing configured to be adapted on a spindle shaft, the integrated needle bearing having a plurality of radial needles arranged parallel to the axis of the spindle shaft, and a plurality of axial needles arranged in a radial formation perpendicular to the radial needles; an inner ring sandwiched between the spindle shaft and the radial needles defining a raceway for the radial needles; a thrust plate mounted on the spindle shaft defining a raceway for the axial needles; and a protection cap mounted on the spindle shaft to cover the thrust plate and the axial needles.
[007] In an embodiment, the integrated needle bearing has a ring configured to receive the radial needles wherein height of the inner ring is substantially same as that of the ring configured to receive the radial needles.

[008] In another embodiment, the integrated needle bearing has an annular plate
configured to receive the axial needles wherein diameter of the thrust plate is
substantially same as that of the annular plate configured to receive the axial
needles.
[009] In yet another embodiment, the integrated need bearing is adapted
circumferentially around the spindle shaft.
[010] In a further embodiment, the radial needles have a static radial load rating
of 37500N, and a dynamic load rating of 22300N. The axial needles 114 have a
static axial load rating of 60000N, and a dynamic radial load rating of 14900N.
BRIEF DESCRIPTION OF THE DRAWINGS
[011] Reference will be made to embodiments of the invention, examples of which may be illustrated in accompanying figures. These figures are intended to be illustrative, not limiting. Although the invention is generally described in context of these embodiments, it should be understood that it is not intended to limit the scope of the invention to these particular embodiments.
Figure 1 shows sectional exploded view of an integrated needle bearing assembly for a spindle shaft in accordance with an embodiment of the present invention.
Figure 2 shows sectional view of an integrated needle bearing assembly adapted on a spindle shaft in accordance with an embodiment of the present invention.

Figure 3 shows integrated needle bearing in accordance with an embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[012] The present invention provides an integrated needle bearing assembly for a spindle shaft, configured to have axial load carrying capacity and radial load carrying capacity.
[013] As shown in Figures 1 and 2, the integrated needle bearing assembly 100 comprises an integrated needle bearing 110, an inner ring 120, a thrust plate 130 and a protection cap 140. The integrated needle bearing assembly 100 is configured to be adapted on a spindle shaft 200. The spindle shaft 200 extends between a first end 210 and a second end 220. In this regard a housing 300 is provided to receive the spindle shaft 200 longitudinally. The first end 210 of the spindle shaft 200 is coupled with a motor that drives the spindle shaft 200. The second end 220 of the spindle shaft 200 is configured to receive a chuck. A drill bit is adapted to the chuck to perform cutting operations.
[014] Referring to Figure 3, the integrated needle bearing 110 has a plurality of radial needles 112 arranged parallel to the axis of the spindle shaft 200 and a plurality of axial needles 114 arranged in a radial formation perpendicular to the radial needles 112. In this regard, the integrated needle bearing has a ring configured to receive the radial needles and an annular plate configured to receive the axial needles. As shown in Figure 2, the integrated needle bearing 110 is adapted circumferentially around the second end 220 of the spindle shaft 200. In

this regard, the inner ring 120 is sandwiched between the spindle shaft 200 and the radial needles 112 of the integrated needle bearing 110 such that the inner ring 120 defines a raceway upon which the plurality of radial needles 112 of the integrated needle bearings 110 rotate. Thus, it is apparent that height of the inner ring 120 will be substantially same as that of the height of the radial needles 112 or that of the ring configured to receive the radial needles 112 such that the radial needles 112 are aptly encapsulated by the inner ring 120.
[015] Further, the thrust plate 130 is mounted circumferentially around the second end 220 of the spindle shaft 200 such that when the integrated needle bearing 110 is mounted circumferentially around the second end 220 of the spindle shaft 200, the thrust plate 130 defines a raceway for rotation of the axial needles 114. Thus, it is apparent that diameter of the thrust plate 130 will be substantially same as that of the diameter of the annular plate carrying the axial needles 114 so that the axial needles 114 are aptly encapsulated by the thrust plate 130.
[016] In an embodiment of the invention, the surfaces of the thrust plate and the inner ring forming respective raceways are greased for providing smooth rotation of the axial needles and the radial needles.
[017] In an embodiment of the invention, as shown in Figures 1 and 2, a protection cap 140 is mounted circumferentially at the second end 220 of the spindle shaft 200. The dimensions of the protection cap 140 are selected such that the protection cap 140 covers the thrust plate 130 and the axial needles 114 in entirety thereby preventing foreign particles from entering the raceways.

[018] In use, the second end 220 of the spindle shaft 200 receives a chuck. A cutting tool such as a drill bit is attached to the chuck. The spindle shaft 200 rotates at a very high speed to enable the tool to perform cutting operation. At this time, the axial needles 114 and the radial needles 112 rotate upon the raceway on the thrust plate 130 and the inner ring 120 respectively. Rotation of the radial needles 112 is parallel to the axis of the spindle shaft 200. Accordingly, radial load generated by spindle shaft 200 is carried by the radial needles 112 of the integrated needle bearing 110. On the other hand, rotation of the axial needles 114 is perpendicular to axis of rotation of the spindle shaft 200. Accordingly, thrust generated during rotation of the spindle shaft 200 is carried by the axial needles 114.
[019] Advantageously, integrated needle bearing assembly of the present invention is separable from the inner ring and the thrust plate. Accordingly, raceways can be replenished with grease as and when required without the need of changing the bearing altogether. Further, if and when the inner ring and/ or thrust plate is worn out by repeated use, only the inner ring and/ or thrust plate needs to be replaced. It is not necessary to replace the entire bearing. This extends the life of the bearings and also makes the operation of the machine more economical. Additionally, the placement of the inner ring is such that it increases the diameter of the second end of the spindle shaft. This adds rigidity and stiffness to the spindle shaft enabling more stable rotation of the spindle shaft.
[020] In an embodiment of the present invention, the bearings have a static radial load rating of 37500 N, and a dynamic radial load rating of 22300 N. In another

embodiment of the present invention, the bearings have a static axial load rating of 60000 N, and a dynamic radial load rating of 14900 N. In a further embodiment of the present invention, the bearings in the integrated bearing assembly are RAX 730 combined thrust bearings.
[021] The foregoing description of the invention has been set merely to illustrate the invention and is not intended to be limiting. Since the modifications of the disclosed embodiments incorporating the spirit and substance of the invention may occur to the person skilled in the art, the invention should be construed to include everything within the scope of the disclosure.

We claim:
1. An integrated needle bearing assembly comprising:
an integrated needle bearing 110 configured to be adapted on a spindle shaft
200, the integrated needle bearing having a plurality of radial needles 112
arranged parallel to the axis of the spindle shaft 200, and a plurality of axial
needles 114 arranged in a radial formation perpendicular to the radial needles
112;
an inner ring 120 sandwiched between the spindle shaft 200 and the radial
needles 112 defining a raceway for the radial needles 112;
a thrust plate 130 mounted on the spindle shaft 200 defining a raceway for the
axial needles 114; and
a protection cap 140 mounted on the spindle shaft 200 to cover the thrust
plate 130 and the axial needles 114.
2. The integrated needle bearing assembly as claimed in claim 1, wherein the integrated needle bearing 110 comprises a ring configured to receive the radial needles 112.
3. The integrated needle bearing assembly as claimed in claim 1, wherein the integrated needle bearing 110 comprises an annular plate configured to receive the axial needles 114.
4. The integrated needle bearing assembly as claimed in claim 2, wherein height of the inner ring 120 is substantially same as that of the ring configured to receive the radial needles 112.

5. The integrated needle bearing assembly as claimed in claim 3, wherein diameter of the thrust plate 130 is substantially same as that of the annular plate configured to receive the axial needles 114.
6. The integrated needle bearing assembly as claimed in claim 1, wherein the integrated need bearing 110 is adapted circumferentially around the spindle shaft 200.
7. The integrated needle bearing assembly as claimed in claim 1, wherein the radial needles 112 have a static radial load rating of 37500N, and a dynamic load rating of 22300N.
8. The integrated needle bearing assembly as claimed in claim 1, wherein the axial needles 114 have a static axial load rating of 60000N, and a dynamic radial load rating of 14900N.