TECHNICAL FIELD

[001] The present subject matter relates in general to a mixer and, in particular, to a blade assembly of the mixer. BACKGROUND

[002] A food processor is an appliance used to facilitate repetitive tasks in the preparation of food and usually refers to an electric-motor-driven appliance. Food processors can carry out several repetitive tasks such as cutting, grinding, chopping, blending, mixing, beating etc. A mixer is a type of food processor that cuts and mixes food material in ajar. A mixer typically has a blade assembly coupled to a jar assembly, which can be in turn coupled to a motor unit. The motor unit provides torque through motor coupler to jar coupler to rotate blade assembly.

[003] Different types of jar assemblies and spare -blade assemblies are provided with the mixer to suit different applications such as grinding, juicing, etc. For example, to use the mixer for dry grinding, a particular blade assembly may be used. To switch the mixer to a different application, such as wet grinding, the blade assembly may have to be changed. In another example, for processing different quantities of food, different jar assemblies may have to be used. Accordingly, the blade assembly may have to be removed from one jar assembly and fixed to another one or spare blades may have to be used for different applications.

[004] Conventionally, a spatula/spanner is used to remove the previously used blade assembly and to fix a different blade assembly. However, in cases where the spatula/spanner is misplaced (which is very common after a period of usage) or hexagonal socket of the spatula/spanner is damaged, the appropriate blade assembly may not be used due to reluctance of user to change blades with bare hands, resulting in sub-optimal usage of the mixer. Furthermore, hindrance in the removal of blade assembly can cause the accumulation of food particles in the blind spots wherein the user's hand cannot reach for cleaning, thereby giving an opportunity for microbial growth and infection. Also, in case the user attempts to change the blade assembly with bare hands accidents may happen since the blades have sharp edges.

BRIEF DESCRIPTION OF DRAWINGS

[005] The detailed description is described with reference to the accompanying figures. In the figures, the left-most digits of a reference number identify the figure in which the reference number first appears. The same numbers are used throughout the drawings to reference like features and components.

[006] Fig. la illustrates a motor unit of a mixer as known in the prior art;

[007] Fig. lb illustrates a jar assembly fitted with a blade assembly as known in the prior art;

[008] Fig. 2a illustrates a cross sectional view of a jar assembly coupled with the blade assembly, in accordance with an embodiment of the present disclosure;

[009] Fig. 2b illustrates a cross sectional view of the jar assembly depicting decoupling of the blade assembly from the jar assembly, in accordance with an embodiment of the present disclosure;

[0010] Fig. 3 illustrates an exploded view of a base assembly of a jar assembly and the blade assembly, in accordance with an embodiment of the present disclosure;

[0011] Fig. 4a illustrates a cross sectional view of a blade assembly, in accordance with an embodiment of the present disclosure;

[0012] Fig. 4b illustrates a cross sectional view depicting a blade assembly fitted to a spindle, in accordance with an embodiment of the present disclosure; and

[0013] Fig. 5 illustrates a perspective view of a snap member of the blade assembly, in accordance with an embodiment of the present disclosure.

[0014] Fig. 6 illustrates a perspective view of a cover of the blade assembly, in accordance with an embodiment of the present disclosure. [0015] Fig. 7 illustrates a perspective view of a push member of the blade assembly, in accordance with an embodiment of the present disclosure.

DETAILED DESCRIPTION

[0016] A mixer typically has a jar assembly, a blade assembly, and a motor unit. Fig. la illustrates a motor unit of a mixer as known in the prior art. The motor unit 100 includes a motor 102, an adaptor 104, a housing 106 to house the motor, a bottom cover 108, and a speed control mechanism (Not marked in the Fig. la). The adaptor 104 helps in holding the jar assembly over the motor unit 100 during operation. The bottom cover 108 includes a non-slip stand so that the mixer does not move during operation. The speed of the motor 102 can be controlled by the speed control mechanism, which includes a switch 110 and a knob 112. The adaptor 104 also includes a motor coupler 114 fitted to a first end of the motor 102, which can be used to couple the motor unit 100 to a jar assembly. The motor coupler 114 helps to transfer the motor torque to a blade assembly of the jar assembly through a jar coupler, as will be described later.

[0017] Fig. lb illustrates a jar assembly fitted with a blade assembly as known in the prior art. The jar assembly 116 includes a jar 118 and a base assembly 120. The base assembly 120 includes a bush 122, a spindle 124, ajar base 126, and ajar coupler 128. A first end of the spindle 124 is to couple with a blade assembly 130. The jar coupler 128 is coupled to a second end of the spindle 124. The spindle 124 is assembled in the bush 122, which is fitted in the jar base 126.

[0018] Further, as illustrated in Fig. lb, the blade assembly 130 includes a blade 132 and a nut 134. The blade 132 is coupled to a first end of the spindle 124 by tightening the nut 134 on top of it.

[0019] Thus, in the prior art, a spatula/spanner has to be used to loosen the nut 134 and remove the blade assembly 130 from the spindle 124, for separating the blade assembly 130 from the jar assembly 116. The spatula/spanner can have, for example, a spanner end to unscrew the nut fitted on the blade and a cleaning end to clean the jar. The blade assembly disclosed in prior art is difficult to assemble and disassemble since it requires an external implement like a spatula. Also, in cases where the spatula is either lost or misplaced, the user may be reluctant to remove the blade and replace it with an alternate blade required for a different application. Therefore, the users tend to not use alternative blades provided with the mixer, which results in sub-optimal performance of the mixer. Also, in the absence of the spatula, the user may injure their hands while trying to assemble/disassemble the blade assembly, since the blades have sharp edges. Further, hindrance in the removal of blade assembly also results in accumulation of food particles in the blind spots where user's hand cannot reach for clean, thereby giving an opportunity for microbial growth and infection.

[0020] The present subject matter provides a blade assembly that is easy to couple to and decouple from a spindle of a jar assembly and does not need any external implement like a spatula. In one embodiment, the blade assembly includes a snap member, a push member, a blade and a cover. The blade assembly is snap-fitted to the jar assembly and therefore, the blade assembly may be easily removed and replaced with a different blade assembly. This makes it easy for the user to use various alternative blades and also helps in effective cleaning of the jar and blades.

[0021] Although the subject matter has been explained in the context of figures that depict a household mixer, it will be understood that the subject matter may be extended to any mixer that includes a replaceable blade assembly, a motor, and a receptacle such as jar, for example, an industrial food mixer.

[0022] Aspects of the present subject matter related to the blade assembly of a mixer will now be described in detail in conjunction with the following figures. It should be noted that the description and figures merely illustrate the principles of the present subject matter along with examples described herein and should not be construed as a limitation to the present subject matter. It is thus understood that various arrangements may be devised that, although not explicitly described or shown herein, embody the principles of the present subject matter. Moreover, all statements herein reciting principles, aspects, and specific examples thereof, are intended to encompass equivalents thereof. [0023] Fig. 2a illustrates a cross sectional view of a jar assembly coupled with a blade assembly, in accordance with an embodiment of the present disclosure. The jar assembly 200 includes a jar 118 coupled to a base assembly 220. The base assembly 220 includes the jar base 126, the jar coupler 128, the bush 122, and a spindle 202. The bush 122 can be, for example, a sintered bronze bush. The spindle 202 is assembled in the bush 122 and coupled to the jar base 126, such that, during use, the spindle 202 is capable of rotation movement about its longitudinal axis but is not capable of linear movement in any direction.

[0024] The blade assembly 204 includes a snap member 206, a push member 208, a cover 210, and a blade 218. The snap member 206 forms a snap fit with the spindle 202. The push member 208 can be used to decouple the snap member 206 from the spindle 202 to remove the blade assembly 204.

[0025] In one embodiment, the push member 208 is substantially cylindrical with one end covered and the other end open. A cross-section of the cylinder may be circular in one example. Further, the push member 208 is hollow in the middle, thereby forming a substantially cup-like structure. However, it will be understood that other shapes and cross-sections of the push member 208 may be used, albeit with a few modifications, without departing from the scope of the present disclosure. The open end of the push member 208 is tapered and narrows down towards the open end. Further, the push member 208 has a rim at the open end that projects radially outward from the taper (not shown in this Fig.).

[0026] In one embodiment, the push member 208 is disposed in the blade assembly 204 with its closed end vertically above the open end. Thus, the cross-section of the push member 208, as shown in Fig. 2a, is substantially inverted-U shape with a closed end 214 and a wedge shaped outer rim 216 at the other end. The push member 208 is disposed over the snap member 206 and accommodates a first end 212 of the spindle 202.

[0027] Further, the snap member 206 has a projection in a central portion (not shown in this Fig.) that can fit into a groove provided in the spindle 202 to couple the snap member 206 with the spindle 202. The blade 218, the snap member 206, and the push member 208 are held together by the cover 210, forming the blade assembly 204.

[0028] In one example, to couple the blade assembly 204 to the spindle 202, the blade assembly 204 can be pushed downwards over the first end 212 of the spindle 202 as shown by the arrow A. The snap member 206 snap-fits to the first end 212 of the spindle 202 when its projection fits into the groove of the spindle 202. This causes the blade assembly 204 to couple to the first end 212 of the spindle 202. As the snap member 206 is snap fitted with the spindle 202, relative movement between the spindle 202 and the blade assembly 204 is avoided during operation.

[0029] In operation, the jar coupler 128 is fitted to a second end of the spindle 202 and is used to couple the jar assembly 200 to the motor coupler 114 of the motor unit 100. The jar coupler 128 receives the motor torque through the motor coupler 114 and causes the spindle 202 to rotate, thereby also causing rotation of the blade assembly 204 that is snap fitted to the spindle 202.

[0030] Fig. 2b illustrates a cross sectional view of the jar assembly depicting decoupling of the blade assembly 204 from the jar assembly 200, in accordance with an embodiment of the present disclosure. In one embodiment, to decouple the blade assembly 204, the closed end 214 of the push member 208 can be pushed downwards from the top as depicted by the arrow B. This causes the snap member 206 to expand laterally as depicted by the arrows C and C and the projection of the snap member 206 to move out of the groove of the spindle 202. As a result, the blade assembly 204 gets decoupled from the spindle 202. The blade assembly 204 can be then removed from the first end 212 of the spindle 202 by being pulled upwards, while keeping the push member 208 pushed downwards. In one example, to make it easy for a user to press the push member 208 downwards, the upper surface of the closed end 214 may have a concave contour for placement of a thumb or finger.

[0031] The blade assembly 204 can therefore be easily coupled to and decoupled from the spindle 202, thereby making it easy for users to change blades and clean the blades and jars. Various parts of the blade assembly 204 that allow the snap fitting and decoupling of the blade assembly 204 will now be described in more detail.

[0032] Fig. 3 illustrates an exploded view of a base assembly of jar assembly and the blade assembly, in accordance with an embodiment of the present disclosure. As shown, the push member 208 is substantially cylindrical and is capable of accommodating a first end 212 of the spindle 202. The cover 210 includes a fastening platform 300 at one end. The fastening platform 300 is capable of being fastened to the blade 218, for example, using rivets 302. In other implementations, other means of fastening, such as screws and the like, may be used and are understood to be covered in the subject matter disclosed.

[0033] In one embodiment, the cover 210 also includes a disc 304 located at an end opposite to the fastening platform 300. The disc 304 of the cover 210 can be used to grip the blade assembly 204 while coupling or decoupling the blade assembly 204 from or to the spindle 202.

[0034] In one embodiment, the snap member 206 has a segmented body divided into two or more flanges 308 forming a substantially circular cross-section. The snap member 206 is hollow in the middle so as to fit over the spindle 202. Further, the snap member 206 has internal projections in a central portion of each of the flanges to snap fit with the groove in the spindle 202. The structure of the snap member 206 will be described in detail later with reference to Fig. 5.

[0035] As shown in Fig. 3, the first end 212 of the spindle 202 is substantially cylindrical. Below the first end 212, various coupling features can be provided, such as threads, washers, nuts, etc., to prevent relative movement between the blade 218 and the spindle 202 when the blade assembly 204 is coupled to the spindle 202. In one embodiment, the coupling features include a square locator 306 on the spindle 202. The square locator 306 on the spindle 202 is capable of aligning with a square slot 310 provided at a center of the blade 218 to ensure that the blade 218 rotates along with the spindle 202. It is to be noted that the coupling features help in holding the blade 218 in position relative to the spindle 202, but do not lock the blade 218 to the spindle 202. As a result, when the blade assembly 204 is decoupled from the spindle 202, the blade assembly 204 can be removed easily by pulling it upwards as is further explained below.

[0036] Fig. 4a illustrates a cross sectional view of a blade assembly 204, in accordance with an embodiment of the present disclosure. The substantially inverted-U shaped cross-section of the push member 208 corresponds to a cylindrical body with a closed end 214. The push member 208 is disposed over the snap member 206 with the wedge shaped outer rim 216 abutting a complimentarily shaped tapered edge 406 of the flanges 308 of the snap member 206. As a result, the push member 208 can slide down the inner side of the flanges 308 of the snap member 206 when the push member 208 is pushed downwards. Further, the inner side of each of the flanges 308 includes at least one projection 408 that can fit into a groove in the spindle 202.

[0037] The snap member 206 and the outer rim 216 of the push member 208 are housed in a first portion 402 of the cover 210, while the cylindrical body of the push member 208 is housed in a second portion 404 of the cover 210. In one embodiment, the internal diameter of the first portion 402 is greater than the internal diameter of the second portion 404 and an internal edge 410 is formed in the cover 210 which connects the first portion 402 and the second portion 404.

[0038] The cylindrical body of the push member 208 can snugly fit into the second portion 404 of the cover 210 with the closed end 214 protruding out of the cover 210. The outer rim 216 abuts against the internal edge 410 of the cover 210 in a normal condition (i.e., when the push member is not pressed downwards). Hence, the internal edge 410 acts as a stopper to prevent the push member 208 from moving upwards and out of the cover 210 in the normal condition. Further, as the first portion 402 has a greater diameter than the second portion 404, it has space for the snap member 206 to expand while being coupled to or decoupled from the spindle 202. The details of the snap member 206 that cooperate with the first end 212 of the spindle 202 to couple / decouple the blade assembly will now be described. [0039] Fig. 4b illustrates a cross sectional view depicting a blade assembly fitted to a spindle, in accordance with an embodiment of the present disclosure.

[0040] As shown, the spindle 202 has a first end 212 and a lower body 414 below the first end 212. The diameter of the lower body 414 is greater than the diameter of the first end 212. This ensures that the push member does not move farther down than required when the push member 208 is pushed downwards to decouple the blade assembly 204 from the spindle 202. The lower body 414 includes at least one circumferential groove 412. The projection 408 on the flanges 308 fits in the circumferential groove 412 to couple the blade assembly 204 to the first end of the spindle 202.

[0041] To couple the blade assembly 204 to the spindle 202, the blade assembly 204 can be pushed downwards on to the spindle 202 without pressing the push member 208. The first end 212 of the spindle 202 passes through the snap member 206 into the push member 208, while the lower body 414 moves into the snap member 206. In one embodiment, the first end 212 of the spindle 202 may be tapered to facilitate easy entry of the spindle 202 into the snap member 206 and push member 208. As the lower body 414 has a greater diameter than the first end 212, it causes flanges 308 of the snap member 206 to expand, i.e., deflect radially outwards, until the projection 408 aligns and fits into the groove 412 of the spindle 202. Since the projection 408 gets locked into the groove 412, further movement of the spindle 202 through the blade assembly 204 is restricted. Thus, the blade assembly 204 gets coupled to the spindle 202.

[0042] To decouple the blade assembly, the push member 208 can be pushed downwards from the top closed end 214, which causes the wedge shaped outer rim 216 to slide down the tapered edge 406 of the snap member 206, in turn causing the snap member 206 to expand due to the flanges 308 deflecting outwards. As a result, the projection 408 gets released from the groove 412 of the spindle 202 and the blade assembly 204 gets decoupled from the first end 212 of the spindle 202.

[0043] The disc 304 (shown in Fig.3) helps a user to grip the cover 210 while pushing the push member 208 downwards to decouple and remove the blade assembly 204. The cover 210 further has a neck below the disc in the second portion 404 to allow for gripping during coupling or decoupling of the blade assembly 204 to or from the spindle 202.

[0044] It will be understood that the snap member 206 can be made of appropriate resilient elastic material that allows the snap member 206 to deform when force is applied during the coupling and decoupling actions and to regain its original form when the force is released. Further, as will be understood by a person skilled in the art, the diameters, cross-sections, and sizes of the push member 208, the snap member 206, and the cover 210 can be appropriately selected, based on the teachings of the present disclosure, to allow them to function as desired and taught by the present disclosure.

[0045] Fig. 5 illustrates a perspective view of a snap member of the blade assembly, in accordance with an embodiment of the present disclosure. As shown, the snap member 206 has a segmented body with two or more flanges 308 forming a substantially circular cross-section when arranged together. In one example, the snap member 206 includes four flanges 308. The segmented structure allows the snap member 206 to expand easily on application of a force, such as when the snap member 206 is to be coupled to or decoupled from the spindle 202. The snap member 206 also includes a support 502 for each flange 308. The support 502 provides strength to the lateral flange and also helps in alignment of the snap member 206 with the cover 210 during assembly. Further, the flanges 308 are arranged on a base plate 504. The base plate 504 helps in alignment and locking of the snap member 206 with the cover 210.

[0046] Fig. 6 illustrates a perspective view of a cover of the blade assembly, in accordance with an embodiment of the present disclosure. As shown, the first portion 402 of the cover 210 includes a cover body 600. In one example, the cover body 600 is substantially cylindrical and hollow in the middle. The fastening platform 300 of the cover body 600 includes at least one means for fastening, for example, rivet hole 602. The rivet hole 602 can receive the rivet 302 for the purpose of fastening the cover 210 to the blade 218. [0047] The second portion 404 of the cover 210 includes a neck portion 604 which is located between the cover body 600 and the disc 304. In one example, the neck portion 604 is substantially cylindrical and has a diameter smaller than that of the disc 304 and of the second portion 404. The smaller diameter of neck portion 604 allows for easy gripping of the cover 210 to couple or decouple the blade assembly 204 to or from the jar assembly. In one example, the disc 304 is substantially annular shaped and can accommodate the push member 208. Further, the cover 210 has an opening 606 in a central area of the disc 304. The opening 606 which is substantially circular and through which a portion of the push member 208 can protrude.

[0048] FIG. 7 illustrates a perspective view of a push member of the blade assembly, in accordance with an embodiment of the present disclosure. As shown, the push member 208 includes a push member body 702 which is closed at one end and open at the opposite end. In an example, the push member body 702 is substantially cylindrical and is hollow in the middle. The push member body 702 can snugly fit into the second portion 404 of the cover 210 such that a portion near the top end of the push member body 702 protrudes from the opening 606 of the cover 210 to facilitate pushing of the push member 208 downwards to decouple the blade assembly 204. The closed end 214 closes the push member body 702 at one end. In one embodiment, the closed end 214 of the push member 208 is substantially convex shaped. However, it will be understood that other shapes such as concave or flat may be used, without departing from the scope of the present disclosure.

[0049] The outer rim 216 of the push member 208 is located at an end opposite to that of the closed end 214. In one example, the outer surface of the outer rim 216 can be formed as substantially truncated-cone to provide the wedge shape. The tapered side of the truncated-cone of the outer rim 216 allows the push member 208 to abut the tapered edge of flanges 406 of the snap member 206. Also, the truncated cone shape allows the outer rim 216 to expand the tapered edge 406 of the flanges 308 and release the snap member 206 from the spindle 202. Also, the outer rim 216 has a wedge-shaped rim 704 which has a diameter greater than that of the push member body 702. This allows the wedge-shaped rim 704 to abut with the internal edge 410 in the cover 210, which prevents the upward movement of the push member body 702 and prevents it from moving outside the cover 210 in normal operation. An inner surface 706 of the outer rim 216 is tapered inwards, which allows the push member 208 to accommodate the first end 212 of the spindle 202.

[0050] Thus, as discussed, the various aspects of the present subject matter provide for easy attachment and removal of blades, thus facilitating usage of different blades for different applications. Further the easy removal of the blade assembly also provides for complete cleaning of mixer jar.

[0051] Although implementations for the blade assembly have been described in language specific to structural features, it is to be understood that the present subject matter is not necessarily limited to the specific features described. Rather, the specific features are disclosed and explained in the context of a few example implementations of the above-mentioned aspects of the present subject matter. List of Reference Numerals:

The list of reference numerals with respect to each feature disclosed along with the drawing, is given below:

122 Bush

124 Spindle of prior art

126 Jar base

128 Jar coupler

130 Blade Assembly of prior art

132 Blade

134 Nut

200 Jar assembly

202 Spindle

204 Blade assembly

206 Snap member

208 Push member

210 Cover

212 First end of spindle

214 Closed end of push member

216 Outer rim of push member

218 Blade

220 Base Assembly

300 Fastening platform

302 Rivets

304 Disc

306 Square locator on the spindle

308 Flanges of snap member

310 Square slot of blade

402 First portion of cover

404 Second portion of cover

406 Tapered edge of flanges of snap member

408 Projection of snap member

410 Internal edge in cover

412 Groove on spindle

414 Lower body of spindle

502 Support for flange

504 Base plate of snap member 600 Cover body

602 Rivet hole

604 Neck portion of cover

606 Opening on cover

702 Push member body

704 Wedge shaped rim

706 Inner surface of outer rim