Claims:1. A food preparation table top wet grinder comprising:-
a) a cylindrical vessel having an inside stone bottom and an inside wall and a volume therewith,
b) a centre axle attached to and positioned vertically in the centre of the vessel,
c) a drive means for driving a motor positioned beneath the vessel connected to rotate the central axle,
d) two conical grinding stones positioned on opposite side of the centre axle for grinding against the vessel’s inside stone bottom, wherein the conical grinding stones are rotated against the inside stone bottom of the vessel by the rotating action of the vessel,
e) a plurality of first surface circular or spiral grooves provided around the external curved surface of the conical grinding stones and the grooves extending generally between the tip and the base of the conical grinding stone,
f) a plurality of additional vertical grooves provided on the external surface in each of the conical grinding stones and wherein the said additional grooves on rotatable conical grinding stones extending linearly along the slant height of the cone from its one end proximate to the tip of the cone and to its other end proximate to the base of the cone of the conical grinding stone,
g) the first surface circular or spiral grooves and the additional vertical grooves on the conical grinding stones divide the stone surface of the conical grinding stone into differentiated passage regions, each of which can be crossed at determined points provided around the conical grinding stone.
2. The food preparation table top wet grinder as claimed in claim 1, wherein the additional vertical grooves taper on depth from the tip to the base of conical grinding stone, such that grooves are deeper towards the tip of conical grinding stone than towards the base of conical grinding stone.

3. The food preparation table top wet grinder as claimed in claim 1, wherein the grooves of one conical grinding stone is aligned with the grooves of the other conical grinding stone.

4. The food preparation table top wet grinder as claimed in claim 1, wherein both the conical grinding stones shall have the first surface circular or spiral grooves (CS) and the additional vertical grooves such that the said additional vertical grooves on both conical stones are additional vertical linear grooves (VL).
5. The food preparation table top wet grinder as claimed in claim 1, wherein both the conical grinding stones shall have the first surface circular or spiral grooves (CS) and the additional vertical grooves such that the said additional vertical grooves on both conical stones are additional vertical slanted grooves (VS).
6. The food preparation table top wet grinder as claimed in claim 1, wherein both the conical grinding stones shall have the first surface circular or spiral grooves (CS) and the additional vertical grooves such that the said additional vertical grooves on one conical stone is additional vertical linear grooves (VL) and the additional vertical grooves on the other conical stone is additional vertical slanted grooves (VS).
7. The food preparation table top wet grinder as claimed in claim 1, wherein the first surface circular or spiral groove may be arranged along a twisted path or a linear path between the tip and base of the conical grinding stones.
8. The food preparation table top wet grinder as claimed in claim 1, wherein the second additional vertical groove may be arranged along a twisted path or a linear path between the tip and base of the conical grinding stone.

9. The food preparation table top wet grinder as claimed in claim 1, wherein the two grinding stones may be positioned on either side of the center axle preferably symmetrically.
, Description:FIELD OF THE INVENTION:

The present invention relates to a wet food grinder, and more particularly to a vertical wet food grinder, which ensures efficiency and improvement over known products in the market.

DESCRIPTION OF THE PRIOR ARTS:

A conventional wet food grinder is used to grind food for many Indian cuisines and it typically has a base, a container and a grinding stone/stones.. The base includes a motor. The container is attached to the base which contains the food that needs to be ground. The grinding stone/stones operationally is attached to the motor of the base, extends into the container and is driven by the motor to grind the food. Hence such conventional wet grinders hitherto known, basically consisted of a base stone, upon which one or more roller stones of either cylindrical or conical cross-section would press against and are held together by gravity, spring force or any other suitable means. The relative motion between the base stone and the roller stones consequent in rubbing and rolling action between the contacting surface and thus the grinding of the food particles took place. The main advantage in this prior art system was that the rubbing between contact surface was grinding the food. But since rubbing action is based on rubbing surface thereby deteriorating the quality of the ground food substance if the surface of the grinding stone and if base was not properly designed.

OBJECT OF INVENTION:

The object of this application is to increase the output of such wet-grinders by reducing the time required to effect a cycle and thereby reducing the grinding time to the food in a wet grinder.

Another object is to provide apparatus for grinding by which the composition food will be uniformly ground and mixed which will be having a uniform consistency.

Another object is to overcome the shortcomings of the prior art, the present invention provides a safety and efficient but simple wet food grinder to mitigate or obviate the aforementioned problems.

Other objects and advantages will be fully explained in the following description and the invention will be more particularly pointed out in the claims.

KNOWN PRIOR ART:

Some of the known prior art are as follows:-
a) 18/MAS/1991 dated 15/05/1991: The grooves “9” of the grinding surface in this application has been worked upon and improved in the present invention.
b) US 9662657 dated 21/01/2014 is also for a multipurpose food grinding machinery, which is near identical to 18/MAS/1991 in so far as the two conical grinding stones and grooves are concerned. The present application is an improvement over this.
c) Few other patents which have been examined are:-
2076/CHE/2008, US 3952958, 962/MAS/1995, CN 102554751.

The intention of this invention is to improve on prior art and eliminate the sufferings short coming and identified in these prior art.

DESCRIPTION OF DRAWINGS:

Fig1 - Straight groove on the conical grinding stone.
Fig 2 - Angular groove on the conical grinding stone.
Fig 3 - Grinder with two conical stones having the two set of grooves with combinations such as two conical stones as of Fig.1 description, two conical stones as of Fig.2description, two conical stones as of Fig. 1 on one side & Fig. 2 on the other side.
Fig 4 – Horizontal type table top wet grinder.
Fig 5 – Another type of horizontal type table top wet grinder.
Fig 6 – Vertical type table top wet grinder.
Fig 7 – Another type of Vertical type table top wet grinder.

DESCRIPTION OF INVENTION:

In the conventional wet grinders, the base stone and the roller stone/stones would be on one side and the motor operationally associated and the base stone deriving its rotary motion through a drive. Such this invention relates to a wet grinding and more particularly, a wet grinder adopted to grind material, into smaller particles, and in the meantime to mix them evenly. Typically the base stone and roller stone have grooves as detailed and illustrated in some of the prior art entered herein. A new concept has been developed in the wet grinder technology in respect of incorporating a few additional grooves on the grinding stones, which has resulted in a technically advanced, compact and a more efficient wet grinder.

This invention relates to grinding and mixing devices for grinding and mixing large quantities of different kinds of food stuffs to make a composition food such as idly dough, vada dough, dosa dough, nut paste, Masala, chutney, chocolate paste all of which are prerequisite in many food preparations including Indian foods and other type of foods, and cuisines and the object is to provide apparatus by which much time and labor and expense can be saved in grinding and mixing the food stuffs and to simplify the mechanism for grinding and mixing the food stuffs so that the grinding and mixing will be much more simple and easily accomplished.

Other characteristics of the invention will become apparent from the description which follows, upon examining the attached drawing which is provided for the purpose of illustration, only, and is not intended to limit the invention. The drawing illustrates schematically a control system conforming to the invention described herein as illustrated in Fig 1-3.

Various apparatuses or processes will be described below to provide an example of an embodiment of each claimed invention. No embodiment described herein limits any claimed invention and any claimed invention may cover processes or apparatuses that are not described below. The claimed inventions are not limited to apparatuses or processes having all of the features of any one apparatus or process described below or to features common to multiple or all of the apparatuses described below. It is possible that an apparatus or process described below is not an embodiment of any claimed invention. The applicants, inventors or owners reserve all rights that they may have in any invention disclosed in an apparatus or process described below that is not claimed in this document, for example the right to claim such an invention in a continuing application and do not intend to abandon, disclaim or dedicate to the public any such invention by its disclosure in this document.

While the description herein provides examples of one or more processes or apparatuses, it will be appreciated that other processes or apparatuses may be within the scope of the accompanying claims.

Type 1
(Figure 4) This horizontal type table top wet grinder has a base frame (1) at the bottom. Motor (2) is located either on right side or left side of the base frame. A drive pulley (3) is connected with the motor. On the other side of the base frame, driven pulley (4) is located. The drive pulley transmits power to the driven pulley via belt (5). The driven pulley drives the flat stone (6) which is located at the bottom of the drum through adaptor (7). Above the flat stone, a pair of roller stones (8) is assembled in the roller holder assembly (9). The pair of roller stones rotates around the centre axis of the roller holder pins by the frictional drive from flat stone. The roller stone assembly is firmly locked by the arm channel (10) present at the top of grinder which provides required spring load to the stones. The arm channel is hinged onto the pillar (11)and gets locked on the motor side. A hatch (12) is placed on the arm channel. Flat stone can rotate in clockwise or anticlockwise direction.

TYPE 2 Same as Type 1 (Figure 5), except the arm channel is hinged and locked on the bracket(13) located on the motor side. There is no pillar arrangement.

TYPE 3
This vertical type table top wet grinder (Figure 6) has a drive unit (14) in the bottom portion. The driven unit consists of a chassis (15) on which Motor (16) is located. A drive pulley is connected with the motor. On the other side of the chassis, driven pulley (17) is located. Drive pulley is connected with the driven pulley using belt drive (18). The driven pulley is linked to two gear trains located above. One gear train (19) drives the roller holder assembly (20) via a centre shaft (21) , unlike Type 1 and Type 2 where roller holder assembly is stationary. Another gear train (22) drives the flat stone (23) opposite to the roller holder assembly through an adaptor (24). A knob assembly (25) is used to lock the drum assembly and to provide required spring load to the grinder. Hatch (26) is placed above the knob assembly. This type can rotate flat stone in both the directions (clockwise and anti-clockwise). Similarly roller holder assembly can also rotate in both the direction (clockwise and anti-clockwise); however, roller holder assembly is made to rotate in opposite direction to the flat stone direction, which means, when roller holder assembly rotates in clockwise direction, flat stone will rotate in anti-clockwise direction and vice versa.

In one aspect the invention relates to a food preparation table top wet grinder. This is comprising of a cylindrical vessel having an inside stone bottom and an inside wall and a volume therewith. A centre axle attached to and positioned vertically in the centre of the vessel. A drive mechanism to obtain a desired speed from the motor is positioned beneath the vessel connected to rotate the central axle. A set of two conical grinding stones (G1G2) positioned on opposite side of the centre axle for grinding against the vessel’s inside stone bottom (B), wherein the conical grinding stones are rotated against the inside stone bottom of the vessel by the rotating action of the vessel. Further plurality of first surface circular or spiral grooves (CS) provided around the external curved surface of the conical grinding stones and the grooves extending generally between the tip and the base of the conical grinding stone. As per the novelty of this invention it includes a plurality of additional vertical grooves (VL,VS) provided on the external surface in each of the conical grinding stones and wherein the said additional grooves on rotatable conical grinding stones extending linearly along the slant height of the cone from its one end proximate to the tip of the cone and to its other end proximate to the base of the cone of the conical grinding stone. The arrangement is such that the first surface circular or spiral grooves and the additional vertical grooves on the conical grinding stones divide the stone surface of the conical grinding stone into differentiated passage regions, each of which can be crossed at determined points provided around the conical grinding stone. Further the additional vertical grooves may extend radially and linearly (VL) along the conical stone between the base and tip of the cone or the additional vertical grooves may extend radially but slanted along the conical stone between the base and tip of the cone.

In another aspect, the food preparation table top wet grinder has the additional vertical grooves taper on depth from the tip to the base of conical grinding stone, such that grooves may be deeper towards the tip of conical grinding stone than towards the base of conical grinding stone. The depth may be variable or may be same through its length also in some cases.

In another aspect of invention, it has grooves of one conical grinding stone may be aligned with the grooves of the other conical grinding stone.

In another aspect of invention, it is such that both conical grinding stones shall have the first surface circular or spiral grooves and the additional vertical grooves.

In another aspect of invention, it is such that one of conical grinding stones shall have the first surface circular or spiral grooves and additional vertical grooves and the second of the conical grinding stone shall have only the first surface circular or spiral grooves.

In another aspect of invention, it is such that the first surface circular or spiral groove may be arranged creating a twisted path or a linear path within the groove which extends between the tip and base of the conical grinding stones.

In another aspect of invention, it is such that the second additional vertical groove may be arranged creating a twisted path or a linear path within the groove which extends between the tip and base of the conical grinding stone.

In another aspect of invention, it is such that the two grinding stones may be positioned on either side of the center axle preferably symmetrically.

In another aspect of invention, it is such that a first and second rotatable conical stones are disposed within the housing such that based on Type 1, 2 and 3 described above, request consultant to fill.

Even though numerous characteristics and advantages of the present invention have been set forth in the foregoing description, together with details of the structure and features of the invention, the disclosure is illustrative only. Changes may be made in the details, especially in matters of shape, size, and arrangement of parts within the principles of the invention to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed. The principal aim of the present invention is to solve the above problems of the known art by providing an improved cutting edge for food grinding machines which substantially reduces the pressure produced during processing, eliminates the possibility of releasing structural particles into the food and maintains a constant density of the distribution.

The operation of the present invention can be easily deduced from the above description: the food to be ground is introduced normally in the grinding machine.The conveyance motion forces the food to pass through the various regions, following the forced path defined between the circular or spiral the grooves which are crossed across by vertical grooves. In following this path, the mass of food passes through these paths, whose depth gradually decrease along the path, thus providing a gradually finer shredding action across the surface of the grinding stones.

In their embodiment, the transfer of the food between the circular or spiral and vertical grooves, is even more facilitated, and food agglomeration risks are practically eliminated by virtue of the food path through the grooves of two types arranged on the surface of the grinding stones.

The innovative step of this invention is in providing the additional vertical grooves, which reduces the time of grinding and improves the quality of the grinding.

In table top wet grinder, the traditional method of grinding process is, when the drum rotates, the flat stone which bonded with drum will also rotate and the roller holder assembly placed above the flat stone which contains roller stone will rotate in the opposite direction with respect to the flat stone.

A force of friction is generated between the flat stone and roller stone. So when a grinding material (rice, dhal, spices, coco nibs, Nuts etc.)flows between them it gets ground easily.

Following are the factors which determines the grinding time and efficiency:
? Contact area :
When contact area increases between the flat stone and roller stone, the materials will grind faster.
? Flow of batter :
More the flow of batter between the flat stone and roller stone , less the grinding time.
? Orientation of cutting edges:
Proper orientation of cutting edges will grind the materials faster.
? Contact time :
The material will grind faster if the number of times of contact between the flat stone and roller stone per unit time increases.

New grooved conical Roller stone:

Among the four factors which determines the grinding efficiency, flow of batter and orientation of cutting edges play a vital role. The contribution of flow of batter is more when compared to the other two factors.

In order to increase the flow of batter, three or more grooves have been added in addition to the earlier grooves. This extra grooves increases the flow of batter between the flat stone and roller stone which reduces the grinding time.

The extra grooves added may be either straight (Fig 1) or Angular (Fig 2). In drum assembly, both stones with straight grooves, both stones with angular grooves, combined straight and angular grooved stones can be used.

The extra grooves provided create a centrifugal force. This makes the batter to flow through the outer large diameter of the stone for more contact which makes better grinding performance. Also, the crossing of cutting edges on account circular/spiral along with vertical grooves helps in grinding faster. This is illustrated in figure 7 (Figure 7).

In one aspect, the outer side of the roller stone should have contact with the flat stone, so the grooves may not be provided up to the maximum diameter side of the roller stone and chamfers may also be provided along the grooves.

The present invention thus conceived is susceptible of numerous modifications and variations, all of which are within the scope of the inventive concept.

All the details may also be replaced with other technically equivalent elements.
In the practical embodiment of the present invention, the materials used, as well as the shapes and the dimensions, may be any according to the requirements without thereby abandoning the scope of the protection of the appended claims.

The present embodiment is for illustrative purposes only. The present invention may be subjected to many modifications and changes without departing from the spirit or essential characteristics as defined by the appended claims.