|Title of Invention||
A DRY GRINDING ATTACHEMENT FOR GRINDING MACHINES
|Abstract||This invention relates to a dry grinding attachment which may be attached to the conventional grinding machines. It consists of two stones interfacing each other, the top stone is rotatable while the bottom stone is non-rotatable. The top stone is provided radially extending grooves from its centre which communicates with the inlet means. The external surfaces of the interfaces are roughened to facilitate smooth grinding and to avoid heating.|
This invention relates to a dry grinding attachment for grinding machines.
Everyday cooking in Indian homes require dry grinding of cereals, pulses and masalas. Conventional methods of manual grinding using stone grinders have now become obsolete, particularly in city homes and modern techniques and devices have been developed to meet consumer demands. Mixies having dry grinding attachment came first but are found to serve only a very limited purpose. Being considerably small, only small quantities may be ground at one time. High speed rotation of the metallic blades generate a lot of heat during the grinding process which affects the quality of the ground material.
Electrically operated dry grinders are commonly used for bulk grinding of cereals, spices and the like. Flour and spice powder obtained by using high powered electrical grinders are inferior in taste and flavour when compared to the products made by using conventional grinding stones. The main reason for this is that the material to be ground gets heated during the process.
The dry grinding attachment of this invention is developed to avoid excessive heating during the grinding process which will help in retaining the original freshness, flavour and colour of the food articles.
The device according to this invention may be attached to any of the existing grinding machines including the tilting and non-tilting wet grinders already available in the market. This
no doubt reduces the financial burden of the consumer. Yet another advantage is that the desired quantity may be ground at home as and when required.
The attachment consists of two circular flat granite stones. The stones are provided centrally with a hollow tubular body integrally formed therewith. The tubular body of the bottom stone is designed to align with the non-rotatable shaft of a conventional wet grinding machine. The top stone is located above the bottom stone, the tubular body of the top and bottom stone communicating with each other and with an opening provided for the supply of materials to be ground. A clamp plate is provided for positioning the stone assembly within the drum of the wet grinder which fits snuggly on the mouth of the drum. The top stone is thus connected to the rotating drum of a conventional wet grinder assembly and gets its drive there from whereas the bottom stone remains non-rotating within the drum.
The inner surface of the top stone is provided with a plurality of grooves extending radially from the central tubular opening and communicating with the grain inlet. The outer periphery of the inner surfaces of both the stones are roughened. The roughened surfaces of these stones face each other and enhances the speed of grinding. The grinding stones are preferably made from granite and are flat and circular.
A dry grinding attachment for grinding machines according to this invention comprises an assembly of a non-rotatable grinding stone and a rotatable grinding stone interfacing each other, each
of the said stones being provided with a centrally located hollow tubular body communicating with each other, the tubular body of the bottom stone being roountable on the non-rotating shaft housed in a rotatable vessel of a conventional grinding machine, a clamping means being provided for rotatably fixing the top stone to the said vessel to derive drive therefrom, the inner surface of the top stone having a plurality of grooves extending radially from its centre, the outer peripheries of the interface of the top and the bottom stones having roughened exteriors, and an inlet means communicating with tubular body of the top stone and the clamping means.
The inlet means is connectable to a hopper for effecting continuous supply of the material to be ground. Since the attachment operates in conjunction with known grinders, elaborate discussion regarding other functional aspects become irrelevant.
This invention will now be described with reference to the single figure in the accompanying drawings.
Fig.I represents an exploded sectional view of the dry grinding attachment according to this invention. Grinding stones of the assembly are represented by reference numeral 4 & 5. S is the non-rotating shaft of a known grinder and D stands for the vessel of the grinder in which the attachment is mounted. Reference numeral 1 is a resting pad on which the attachment rests when mounted while numerals 2 and 3 are nut and bush respectively. An adapter plate 9 is provided on top of the rotatable grinding stone, whereas numerals 6, 7 and 8 are
locating ring and nut for fixin the top grinding stone. A clamping means such as a clamping plate or bracket assembly 15 is fixed to the mouth of the drum D with the help of clamping assembly represented by 16, 17, 18 and 20. A hopper 21 communicates with the rotatable grinding stone through a throat indicated by reference numeral 19. Reference numerals 11 to 14 relate to conventional means like lock, nut, nut washer and stud for assembling the attachment.
When mounted within the drum and operatively connected thereto the attachment performs grinding without excessive heating and the relatively high speed. The groove provided on the inner surface of the top roller facilitates smooth movement of the material to the roughened outer surface in contact with each other. Grain fed from the hopper enters the grinding stone through the throat and the tubular body and gets crushed due to the rotational movement of the top stone which derives drive from the rotating drum of the conventional grinder. The ground material collects within the drum and can be periodically removed.
Though this invention has been described herein above with a specific embodiment, obvious modifications known to persons skilled in the art are within its scope and that of the appended claims.
1. A dry grinding attachment for grinding machines comprising an assembly of a non-rotatable grinding stone (4) and a rotatable grinding stone (5) interfacing each other each of the said stones being provided with a centrally located hollow tubular body communicating with each other, the said tubular body of the bottom stone being mountable on the non-rotating shaft housed in a rotatable vessel (D) of a conventional grinding machine, a clamping means (15) being provided for rotatably fixing the top stone to the said vessel (D) to derive drive therefrom, the inner surface of the said top stone having a plurality of grooves extending radially from its centre, the outer peripheries of the interface of the top and the bottom stones having roughened exteriors, and an inlet means communicating with tubular body of the top stone and the clamping means.
2. The dry grinding attachment as claimed in claim 1, wherein an adapter plate (9) is provided in between the top stone and the clamping means.
3. The dry grinding attachment as claimed in claims 1 and 2 wherein a resting pad (1) is provided for seating the non-rotatable stone in the said vessel.
4. The dry grinding attachment as claimed in claims 1-3 wherein the grinding stones are of granite and are circular and flat.
S. The dry grinding attachment as claimed in claims 1-4 wherein the inlet means is provided with a hopper.
6. A dry grinding attachment for grinding machines substantially as herein described, with reference to Fig.I of the accompanying drawings.
|Indian Patent Application Number||1562/MAS/1998|
|PG Journal Number||07/2008|
|Date of Filing||13-Jul-1998|
|Name of Patentee||RANGASWAMY NAIDU DORAISWAMY|
|Applicant Address||PB NO. 1608, 480-A AVANASHI ROAD, PEELAMEDU, COIMBATORE 641004,|
|PCT International Classification Number||B02C 9/00|
|PCT International Application Number||N/A|
|PCT International Filing date|