FORM 2
THE PATENTS ACT, 1970
(39 OF 1970)
&
THE PATENT RULES, 2003
COMPLETE SPECIFICATION
(See secton 10 and rule 13)
“A BLADE FOR A MIXER GRINDER JAR”
We, Bajaj Electricals Limited, an Indian Natonal, of, 45/47, Veer Nariman Road, Fort, Mumbai - 400001, Maharashtra, India.
The following specifcaton partcularly describes the inventon and the manner in which it is to be performed:

FIELD OF INVENTION
The present invention relates to electric kitchen appliances. Particularly, the present invention relates to a mixer grinder. More particularly, the present invention relates to a blade for a mixer grinder jar.
BACKGROUND OF THE INVENTION
Mixer grinder jars generally comprises a base configured to engage with a motor disposed on a mixer grinder, a shell or enclosure defining a mixing/grinding container, a lid for accessing/closing the Jar and a blade assembly disposed in a mixing container. Such jars are configured to be fitted on a grinder wherein motor rotates the blade(s)provided at the base of the jar to mix/grind or blend food and other contents. The blade(s) are usually deal with different ingredients and recipes and supposed to run on a longer duration.
It has been seen that wider variety of foods having different density requires more power and blending time. The increased torque and speed from the motors and the longer blend times can put greater stress on the blades and blade assemblies which could accelerate breakage/failing of the blades thereby results in decreasing the life of the blades.
Therefore, there is need for a blade for a mixer grinder jar that has a high degree of operational reliability and a high cutting performance which can overcome one or more limitations stated above or any other limitations associated with the prior art.
SUMMARY OF THE INVENTION
This section is intended to introduce certain objects of the disclosed method and system in a simplified form, and is not intended to identify the key advantages or features of the present disclosure.
In an aspect of the present invention, there is provided a blade for a mixer grinder jar comprising: a base section having at least an aperture defining an axis of rotation of the blade; and at least two wing sections extending from the base section, said wing section comprising a first wing section, a second wing section, and a winglet, wherein said first wing section, second wing section, and winglet are at an angle to each other, wherein a proximal end of the

first wing section is in connection with an end of the base section; the distal end of the first wing section is in connection with the proximal end of the second wing section; the distal end of the second wing section is in connection with the proximal end of the winglet; and the distal end of the winglet is a free end.
In an aspect of the present invention, the aperture is adapted to receive an operating shaft for providing rotational movement of the blade in the mixer grinder jar.
In another aspect of the present invention, the blade has a thickness in the range of 1.5 mm to 2 mm.
In another aspect of the present invention, the base section has a width in the range of 21 mm to 24 mm.
In yet another aspect of the present invention, the wing section has a width in the range of 10 mm to 24 mm.
In yet another aspect of the present invention, the first wing section is sloped downwards of the plane of the base section and the plane of the first wing section is provided at an angle (h) with respect to the plane of the base section, wherein the angle (h) is in the range of 30 degrees to 60 degrees.
In still another aspect of the present invention, the plane of the second wing section is sloped upwards from the plane of the base section by an angle (e) in the range of 0 degrees to 5 degrees.
In an aspect of the present invention, the winglet is sloped upwards of the plane of the second wing section and the plane of the winglet is provided at an angle (c) with respect to the plane of the second wing section, wherein the angle (c) is in the range of 100 degrees to 110 degrees.
In another aspect of the present invention, the first wing section is provided at an angle (a) (bend line) with respect to an axis perpendicular to the axis of rotation of the blade, and angle (a) is in the range of 10 degrees to 30 degrees.

In still another aspect of the present invention, the second wing section is provided at an angle (b) with respect to an axis perpendicular to the axis of rotation of the blade and parallel to the base section, wherein angle (b) is in the range of 35 degrees to 55 degrees.
In yet another aspect of the present invention, at least a region of at least the first wing section, the second wing section, or the winglet is provided with a plurality of serrations.
In an aspect of the present invention, the wing section comprises a leading edge and a trailing edge, said leading edge comprising at least a cutting edge.
In another aspect of the present invention, there is provided a mixer grinder comprising: a base configured to attach and engage with a motor disposed on a mixer grinder; an enclosure defining a mixing or grinding container; an operating shaft provided at the base, wherein the operating shaft is configured to attach with the motor and rotate a blade comprising a base section having at least an aperture defining an axis of rotation of the blade; and at least two wing sections extending from the base section, said wing section comprising a first wing section, a second wing section, and a winglet, wherein said first wing section, second wing section, and winglet are at an angle to each other, wherein a proximal end of the first wing section is in connection with an end of the base section; the distal end of the first wing section is in connection with the proximal end of the second wing section; the distal end of the second wing section is in connection with the proximal end of the winglet; and the distal end of the winglet is a free end; and a handle attached to the enclosure of the mixer grinder jar.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS
In order to explain the technical solution in the embodiments of the present application more clearly, the drawings used in the description of the embodiments will be briefly introduced below. It is obvious that the drawings in the following description are only some embodiments of the application. For those skilled in the art, without any creative work, other drawings can be obtained based on these drawings.

It is to be noted, however, that the appended drawings only illustrate typical embodiments of the present subject matter, and are therefore, not to be considered for limiting of its scope, for the subject matter may admit to other equally effective embodiments.
Fig. 1 depicts a perspective view of a blade of a mixer grinder, in accordance with an embodiment of the present invention.
Fig. 2 depicts a side-view of a blade of a mixer grinder, suitable for dry materials in accordance with an embodiment of the present invention.
Fig. 3 depicts a perspective view of a blade of a mixer grinder suitable for dry materials, in accordance with an embodiment of the present invention.
Fig. 4 depicts a side-view of a blade of a mixer grinder suitable for grinding/mixing dry and wet materials, in accordance with another embodiment of the present invention.
Fig. 5 depicts an exploded view of a mixer grinder jar comprising various structural components, including a blade, in accordance with yet another embodiment of the present invention
DETAILED DESCRIPTION OF THE INVENTION
In the following description, for the purposes of explanation, various specific details are set forth in order to provide a thorough understanding of embodiments of the present invention. It will be apparent, however, that embodiments of the present invention may be practiced without these specific details. Several features described hereafter can each be used independently of one another or with any combination of other features. An individual feature may not address any of the problems discussed above or might address only one of the problems discussed above.
Some of the problems discussed above might not be fully addressed by any of the features described herein. Exemplified embodiments of the present invention are described below, as illustrated in various drawings in which like reference numerals refer to the same parts throughout the different drawings.

The terms "comprises", "comprising", or any other variations thereof, are intended to cover a non-exclusive inclusion, such that an assembly, setup, system, device that comprises a list of components does not include only those components but may include other components not expressly listed or inherent to such system or device or setup. In other words, one or more elements in the system or apparatus or device proceeded by "comprises a" does not, without more constraints, preclude the existence of other elements or additional elements in the assembly or system or apparatus or device.
The present invention provides a blade for a mixer grinder jar comprising: a base section having at least an aperture defining an axis of rotation of the blade; and at least two wing sections extending from the base section, said wing section comprising a first wing section, a second wing section, and a winglet, wherein said first wing section, second wing section, and winglet are at an angle to each other, wherein a proximal end of the first wing section is in connection with an end of the base section; the distal end of the first wing section is in connection with the proximal end of the second wing section; the distal end of the second wing section is in connection with the proximal end of the winglet; and the distal end of the winglet is a free end.
The aperture of the base section of the blade is adapted to receive an operating shaft for providing rotational movement of the blade during operation of the mixer grinder. In an embodiment, the base section comprise a single aperture. In an embodiment, the aperture is substantially circular in shape. In another embodiment, the aperture has a defined number of sides. In an embodiment, the aperture has 4 sides. In another embodiment, the aperture has 6 sides. In yet another embodiment, the aperture has 8 sides. In an embodiment, the aperture is reversibly attaches to the operating shaft by a snap fit arrangement. In an embodiment, the aperture is adapted to reversibly attach to the operating shaft by any other means generally known to a person skilled in the art.
The blade has a thickness in the range of 1.5mm to 2mm. In an embodiment, the thickness of the blade is uniform. In another embodiment, the blade has at least 2 different thickness in at least two different sections of the blade. The width of the base section of the blade is in the range of 21mm to 24mm. In an embodiment, the width is uniform. In another embodiment,

the width is non-uniform. In an embodiment, the base section is tapered towards the edges of the base section along the length of the base section.
The width of the wing section of the blade in in the range of 10mm to 24mm. In an embodiment, the width of the wing section is uniform. In another embodiment, the width of the wing section is not uniform. In an embodiment, the wing section has at least a first width and a second width. In an embodiment, the width of the first wing section is different than that of the second wing section and/or winglet. In yet another embodiment, the width of the second wing section is different than that of the first wing section and/or winglet. In still another embodiment, the width of the winglet is different than that of the first wing section and/or second wing section. In an embodiment, the width of first wing section, second wing section, and winglet is different. In an embodiment, the width of at least two of first wing section, section wing section, and winglet is same. In an embodiment, the width of at least two of first wing section, section wing section, and winglet is different.
In an embodiment, the blade comprises 2 wing sections. In another embodiment, the blade comprises 3 wing sections. In yet another embodiment, the blade comprises 4 wing sections. In a preferred embodiment, the plurality of wing sections are identical to each other.
The first wing section of the wing section of the blade is sloped downwards of the plane of the base section and the plane of the first wing section is provided at an angle (h) with respect to the plane of the base section. Angle (h) is in the range of 30 degrees to 60 degrees. In a preferred embodiment, angle (h) is 60 degrees. In another preferred embodiment, angle (h) is 30 degrees.
The plane of the second wing section of the wing section of the blade is sloped upwards from the plane of the base section by an angle (e). Angle (e) is in the range of 0 degrees to 5 degrees. In a preferred embodiment, angle (e) is 0 degrees. In another preferred embodiment, angle (e) is 5 degrees. Lift angle (e) helps to reduce the total load on the blade by providing a clearance for the material to move around the blade.

The winglet of the wing section of the blade is sloped upwards of the plane of the second wing section and the plane of the winglet is provided at an angle (c) with respect to the plane of the second wing section. The angle (c) is in the range of 100 degrees to 110 degrees.
The first wing section of the blade is provided at an angle (a) (bend line) with respect to an axis perpendicular to the axis of rotation of the blade. Angle (a) is in the range of 10 degrees to 30 degrees. In a preferred embodiment, angle (a) is 15 degrees. Angle (a) increases blade strength by increasing the section modulus along the force transfer line (f), thereby improving the life of the blade (see Fig. 3).
The second wing section of the blade is provided at an angle (b) with respect to an axis perpendicular to the axis of rotation of the blade and parallel to the base section. Angle (b) is in the range of 35 degrees to 55 degrees. In a preferred embodiment, angle (b) is 45 degrees. Angle (b) increases slice-push ratio, which improves the cutting efficiency of the blade and decreases the load on the blade, thereby improving the life of the blade. The slice-push ratio, i.e., velocity parallel to the cutting edge/blade displacement or velocity perpendicular to the cutting edge is an important parameter defining the easiness and effectiveness of cutting. The greater the slice-push ratio, better and easier the cutting. During working, when the material approaches a stationary blade whose normal is inclined at an angle to direction of its motion, a slice-push effect exists because the approach feed velocity components present parallel to the edge of the blade and perpendicular to the edge. So, best slice-push ratio is obtained with the steepest inclination, which is further optimized to be between 35 degrees to 55 degrees.
The wing section of the blade comprises a leading edge and a trailing edge. The leading edge comprises at least a cutting edge. In an embodiment, the first wing section is provided with a cutting edge. In an embodiment, the second wing section is provided with a cutting edge. In yet another embodiment, the winglet is provided with a cutting edge. In an embodiment, at least one of first wing section, second wing section, and winglet is provided with a cutting edge. In still another embodiment, at least two of first wing section, second wing section, and winglet is provided with a cutting edge.

At least a region of the wing section is provided with a plurality of serrations. In an embodiment, a plurality of serrations are provided on the first wing section. In an embodiment, a plurality of serrations are provided on the second wing section. In an embodiment, a plurality of serrations are provided on the winglet. In an embodiment, a plurality of serrations are provided on at least one or more of first wing section, second wing section, and winglet. In a preferred embodiment, a plurality of serrations are provided on the second wing section. In another preferred embodiment, a plurality of serrations are provided at the intersection between first wing section and second wing section.
In an embodiment, the blade is suitable for mixing/grinding dry materials. In another embodiment, the blade is suitable for mixing/grinding a mixture of at least a dry material and at least a liquid. Dry materials include, but is not limited to spices. Mixture of at least a dry material and at least a liquid include, but is not limited to at least a spice and water. Dry material can also include vegetables, fruits, and the like. Liquid can also include milk, oil, and the like.
There is also provided a mixer grinder comprising: a base configured to attach and engage with a motor disposed on a mixer grinder; an enclosure defining a mixing or grinding container; an operating shaft provided at the base, wherein the operating shaft is configured to attach with the motor and rotate a blade, said blade as substantially described herein; and a handle attached to the enclosure of the mixer grinder jar.
Referring to Fig. 1, there is provided a blade (100) comprising a base section (110) having an aperture (112), which defines the axis of rotation of the blade (100). The blade (100) further comprise 2 wing sections (120) extending from the base section (110) and are diametrically opposite each other. Each wing section (120) comprises a first wing section (122), a second wing section (124), and a winglet (126). A first end of the first wing section (122) is in fluid communication with a first end of the base section (110) and a second end of the first wing section (122) is in fluid communication with a first end of the second wing section (124). A second end of the second wing section (124) is in fluid communication with a first end of the winglet (126). The blade (100) is particularly suited for dry material mixing/grinding. The connection region between the first wing section (122) and the second

wing section (124) is provided with a plurality of serrations. The plurality of serrations cover the connection region and extend partly into the first wing section (122) and the second wing section (124).
Referring to Fig. 2, which is a side-view of the blade (100) as also shown in Fig. 1, the plane of the base section (110) is at an angle of 90 degrees to the axis perpendicular to the rotation of the blade (100). The first wing section (122) is sloped downwards from the base section (110) and plane of the base section (110) and the plane of the first wing section (122) forms an angle (h) of 60 degrees. The lift angle (e) of the second wing section (124) is 5 degrees. The lift angle (e) is defined as the angle formed by the intersection of the plane of the base section (110) and plane of the second wing section (124). The winglet (126) is provided at an angle (c) of 110 degrees as measured from the plane of the second wing section (124).
Referring to Fig. 3, the bend line angle (a), which is formed between the first wing section (122) and axis perpendicular to the axis of rotation of the blade (100) is 15 degrees. The angle (b) formed by the second wing section (124) and axis perpendicular to the axis of rotation of the blade (100) and parallel to the base section (110) is 45 degrees.
Referring to Fig. 4, which is a side-view of a blade (100) that is particularly suited for mixing/grinding/ mixture of dry material(s) and liquid to obtain a “paste”. In contrast to the blade (100) suited for dry material mixing/grinding, the blade (100) as depicted in Fig. 4 has lift angle (e) of 0 degrees. Further, the blade (100) has a plurality of serrations primarily in the second wing section (124). Referring to Fig. 3 and 4, for the blade (100) suited for mixing/grinding/ mixture of dry material(s) and liquid, the bend line angle (a), which is formed between the first wing section (122) and axis perpendicular to the axis of rotation of the blade (100) is 15 degrees. The angle (b) formed by the second wing section (124) and axis perpendicular to the axis of rotation of the blade (100) and parallel to the base section (110) is 45 degrees.
Referring to Fig. 5 (exploded view), there is provided a mixer grinder jar (10) comprising a base (11) configured to attach and engage with a motor disposed on the mixer grinder; an enclosure (12) defining the mixer grinder container; an operating shaft (14) provided at the

base (11), which is configured to attach with the motor and rotate a blade (100) as substantially described in this specification; and a handle (not shown) of the container (12) of the mixer grinder. The mixer grinder jar (10) also comprises a lid to close the jar during operation (not shown).
Tests have been conducted to ascertain the blade life, which is as follows:
Testing procedure:
Testing was done with turmeric – 150g in each cycle, where each piece of turmeric was approximately 1cm long and substantially dry.
Moisture removal was done by microwaving the turmeric piece for 30-60 seconds and then allowed to cool at room temperature.
Each cycle testing procedure was run 1st speed for 15 seconds; 2nd speed for 15 seconds; and 3rd speed for 30 seconds.

Life test results
Prior art Present invention
Thickness 1.5mm 1.8mm
Average number of cycles 36 107
While considerable emphasis has been placed herein on the particular features of this invention, it will be appreciated that various modifications can be made, and that many changes can be made in the preferred embodiments without departing from the principles of the invention. These and other modifications in the nature of the disclosure or the preferred embodiments will be apparent to those skilled in the art from the invention herein, whereby it is to be distinctly understood that the foregoing descriptive matter is to be interpreted merely as illustrative of the invention and not as a limitation.
REFERENCE NUMERALS
(10) – mixer grinder jar

(11) – base
(12) – enclosure (14) – operating shaft (100) – blade
(110) – base section (112) – aperture (120) – wing section (122) – first wing section (124) - second wing section (126) – winglet

I/We claim:
1. A blade (100) for a mixer grinder jar (10) comprising:
a base section (110) having at least an aperture (112) defining an axis of rotation of the blade (100); and
at least two wing sections (120) extending from the base section (110), said wing section (120) comprising a first wing section (122), a second wing section (124), and a winglet (126),
wherein said first wing section (122), second wing section (124), and winglet (126) are at an angle to each other,
wherein a proximal end of the first wing section (122) is in connection with an end of the base section (110); the distal end of the first wing section (122) is in connection with the proximal end of the second wing section (124); the distal end of the second wing section (124) is in connection with the proximal end of the winglet (126); and the distal end of the winglet (126) is a free end.
2. The blade (100) as claimed in claim 1, wherein the aperture (112) is adapted to receive an operating shaft for providing rotational movement of the blade (100) in the mixer grinder jar (10).
3. The blade (100) as claimed in claim 1, wherein the blade (100) has a thickness in the range of 1.5 mm to 2 mm.
4. The blade (100) as claimed in claim 1, wherein the base section (110) has a width in the range of 21 mm to 24 mm.
5. The blade (100) as claimed in claim 1, wherein the wing section (120) has a width in the range of 10 mm to 24 mm.
6. The blade (100) as claimed in claim 1, wherein the first wing section (122) is sloped downwards of the plane of the base section (110) and the plane of the first wing

section (122) is provided at an angle (h) with respect to the plane of the base section (110), wherein the angle (h) is in the range of 30 degrees to 60 degrees.
7. The blade (100) as claimed in claim 1, wherein the plane of the second wing section (124) is sloped upwards from the plane of the base section (110) by an angle (e) in the range of 0 degrees to 5 degrees.
8. The blade (100) as claimed in claim 1, wherein the winglet (126) is sloped upwards of the plane of the second wing section (124) and the plane of the winglet (126) is provided at an angle (c) with respect to the plane of the second wing section (124), wherein the angle (c) is in the range of 100 degrees to 110 degrees.
9. The blade (100) as claimed in claim 6, wherein the first wing section (122) is provided at an angle (a) (bend line) with respect to an axis perpendicular to the axis of rotation of the blade (100), and angle (a) is in the range of 10 degrees to 30 degrees.
10. The blade (100) as claimed in claim 7, wherein the second wing section (124) is provided at an angle (b) with respect to an axis perpendicular to the axis of rotation of the blade (100) and parallel to the base section (110), wherein angle (b) is in the range of 35 degrees to 55 degrees.
11. The blade (100) as claimed in claim 1, wherein at least a region of at least the first wing section (122), the second wing section (124), or the winglet (126) is provided with a plurality of serrations (130).
12. The blade (100) as claimed in claim 1, wherein the wing section comprises a leading edge (104) and a trailing edge (106), said leading edge (104) comprising at least a cutting edge.
13. A mixer grinder jar (10) comprising:

a base (11) configured to attach and engage with a motor disposed on a mixer grinder;
an enclosure (12) defining a mixing or grinding container;
an operating shaft (14) provided at the base (11), wherein the operating shaft (112) is configured to attach with the motor and rotate a blade (100) as claimed in claim 1; and
a handle attached to the enclosure (12) of the mixer grinder jar (10).