US3131875A - Method of and apparatus for grinding a solid in a liquid - Google Patents

Method of and apparatus for grinding a solid in a liquid Download PDF

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US3131875A
US3131875A US132057A US13205761A US3131875A US 3131875 A US3131875 A US 3131875A US 132057 A US132057 A US 132057A US 13205761 A US13205761 A US 13205761A US 3131875 A US3131875 A US 3131875A
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grinding
elements
agitating
liquid
edge
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US132057A
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Szegvari Andrew
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B02—CRUSHING, PULVERISING, OR DISINTEGRATING; PREPARATORY TREATMENT OF GRAIN FOR MILLING
    • B02C—CRUSHING, PULVERISING, OR DISINTEGRATING IN GENERAL; MILLING GRAIN
    • B02C17/00—Disintegrating by tumbling mills, i.e. mills having a container charged with the material to be disintegrated with or without special disintegrating members such as pebbles or balls
    • B02C17/16—Mills in which a fixed container houses stirring means tumbling the charge
    • A—HUMAN NECESSITIES
    • A23—FOODS OR FOODSTUFFS; TREATMENT THEREOF, NOT COVERED BY OTHER CLASSES
    • A23G—COCOA; COCOA PRODUCTS, e.g. CHOCOLATE; SUBSTITUTES FOR COCOA OR COCOA PRODUCTS; CONFECTIONERY; CHEWING GUM; ICE-CREAM; PREPARATION THEREOF
    • A23G3/00—Sweetmeats; Confectionery; Marzipan; Coated or filled products
    • A23G3/02—Apparatus specially adapted for manufacture or treatment of sweetmeats or confectionery; Accessories therefor
    • A23G3/0205—Manufacture or treatment of liquids, pastes, creams, granules, shred or powder
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F9/00—Making metallic powder or suspensions thereof
    • B22F9/02—Making metallic powder or suspensions thereof using physical processes
    • B22F9/04—Making metallic powder or suspensions thereof using physical processes starting from solid material, e.g. by crushing, grinding or milling
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B24—GRINDING; POLISHING
    • B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
    • B24B31/00—Machines or devices designed for polishing or abrading surfaces on work by means of tumbling apparatus or other apparatus in which the work and/or the abrasive material is loose; Accessories therefor
    • B24B31/10—Machines or devices designed for polishing or abrading surfaces on work by means of tumbling apparatus or other apparatus in which the work and/or the abrasive material is loose; Accessories therefor involving other means for tumbling of work

Definitions

  • FIG. 2 I METHOD OF AND APPARATUS FOR GRINDING A SOLID IN A LIQUID Filed Aug. 17, 1961 INVENTUR. ANDREW SZEGVARI Bi /Mm ATTORNEY FIG. 2
  • the grinding elements are substantially spherical, and all are of substantially the same size. They may be composed of metal, stone, or the like. They are put into motion and then kept in substantially constant motion out of static contact with one another by moving one or more agitator blades horizontally through a mass of them in a vessel.
  • the improvement of this invention is in the shape of the agitator blade or blades and the improved grinding action which results from their use.
  • the blade is streamlined with a thin forward edge which tapers to a blunt rear edge, its cross section being substantially that of the vertical cross section of a tear drop. It is moved through the grinding elements in the direction opposite to that in which an airfoil moves through the air because the airfoil is shaped to cause minimum agitation of the air, particularly at its rear edge, and it is the function of the agitator blade to cause maximum agitation of the grinding elements, with minimum consumption of energy.
  • FIG. 1 is an elevation of an empty grinding vessel equipped with an agitator provided with blades of the invention
  • FIG. 2 is an enlarged detail of a corner of the vessel, the grinding elements being much closer together than illustrated, in actual practice;
  • FIG. 3 is a section through a blade on the line 33 of FIG. 2, with a schematic showing of how the grinding elements are agitated.
  • the vessel 5, of S-gallon capacity contains a large number of steel balls 6, each measuring inch in diameter.
  • the grinding elements may vary in size from fine sandsized particles, e.g. inch in diameter to elements ii; inch in diameter or larger, depending upon the size of the vessel, the nature of the material to be ground, etc.
  • the vessel is filled with these elements to a depth to cover the top blade of the agitator.
  • the agitator comprises a number of evenly spaced agitator blades 8 which project from the vertical shaft 9 which is adapted to be rotated at a speed of 50 to 300 revolutions per minute, depending upon the material subjected to treatment, the ultimate particle size desired, etc.
  • the outer ends of the blades are spaced about inch (three times an element diameter) from the wall of the vessel to prevent jamming of the elements in that space.
  • the agitator may be used for dry grinding, or the grinding of a suspension from which the grinding elements quickly settle. It may be used for grinding extremely hard materials, and the rapid grinding of softer materials, and the processing of sensitive materials such as biological preparations, medicinals, and other edible products in which more than a trace of impurities derived from the wall structure of the grinding vessel is objectionable. Thus, it may be used for grinding tungsten carbide, paint pigments, coal, procain penicillin and many, many other materials. Where suitable they may be ground dry, although usually they will be ground in suspension in water or other thinly fluid liquid. The hardness, etc. required in the grinding elements will depend upon the material subjected to treatment. Vessels of several hundred gallons capacity can be used. Several agitators of the type shown, all rotated in the same direction, may be used in a single vessel.
  • the agitator arm In grinding, the agitator arm is moved with the thin edge forward at a suflicient speed to keep the elements (except those adjacent the bottom and the wall of the vessel) out of static contact with one another. They are suspended in the liquid, and are directed toward each other due to the negative hydrostatic pressure caused by different sides of the same airfoil-shape agitator means. They are in substantially constant motion throughout the grinding operation, bouncing against one another and grinding the material in their respective paths. The action of the elements is more particularly described in said U.S. 2,764,359.
  • the vessel may be tipped to empty its contents, or it may be provided with suitable valve means 10, which may be of the type described in said U.S. 2,764,- 359 which retains the grinding elements in the vessel while permitting the discharge of a liquid suspension or" the ground product.
  • apparatus for grinding a solid in a liquid which includes in a vessel, many substantially spherical grinding elements all of substantially the same size, and at least one substantially horizontal elongated element adapted to be rotated about an axis at sufiicient speed for maintaining the grinding element out of static contact with one another, the improvement in which said elongated element is streamlined and has a cross section substantially that of the vertical cross section of a tear drop, with means for moving the elongated element with the thin edge thereof the leading edge, whereby agitation of grinding elements is accelerated immediately to the rear of the elongated element as it is moved through the grinding elements.
  • the improvement which comprises moving through the elements streamlined agitating means which has a cross section substantially that of the vertical cross section of a tear drop, with its thin edge forward and by the subsequent passage of the blunt edge through the agitating elements directing them toward one another at the rear of the agitating means as it is moved through the liquid due to the negative hydrostatic pressure caused by the passage of the different sides of the same agitating means through the liquid, and moving the agitating means at a sufficient speed to maintain the grinding elements out of static contact with one another.
  • a grinding or mixing process performed by contacting balls or grinding elements which are part of a liquid system, whereby these elements are moved into contact primarily by producing hydrodynamic flow behind a moving streamlined agitator arm which broadens gradually backwardly from a pointed front edge and has a blunt 7 rear, thereby keeping the elements in substantially constreamlined agitator arm which has a thin forward edge and tapers backwardly to a blunt rear edge, through grinding elements out of static contact with one another in a medium that behaves like a liquid whereby the elements are moved into contact behind the agitator arm primarily because of hydrodynamic flow existing behind the agitator arm and produced by the movement of the agitator arm and thereby kept in substantially constant motion out of static contact with one another.
  • apparatus for grinding a solid in a liquid which includes a vessel, a liquid in the vessel, many substantially spherical grinding elements all of substantially the same size suspended in the liquid out of static contact with one another, and at least one substantially horizontal elongated element adapted to be rotated about a'ver tical axis for maintaining the grinding elements suspended in the liquid, the improvement in which said elongated element has a cross section substantially that of a tear drop with the thin edge thereof the leading edge and free of all sharp edges to the rear of said leading edge, whereby agitation of the grinding elements is accelerated immediately to the rear of the elongated element primarily by hydrodynamic fiow as the elongated element is moved 10 through the grinding elements.

Description

y 5, 1964 A. SZEGVARI 3,131,875
I METHOD OF AND APPARATUS FOR GRINDING A SOLID IN A LIQUID Filed Aug. 17, 1961 INVENTUR. ANDREW SZEGVARI Bi /Mm ATTORNEY FIG. 2
United States Patent 3,131,875 METHOD OF AND APPARATUS FOR GRINDING A SOLID IN A LIQUID Andrew Szegvari, 120 Ash St., Akron 8, Ohio Filed Aug. 17, 196i, Ser. No. 132,057 Claims priority, application Japan Sept. 5, 1960 6 Claims. (Cl. 24127) This invention relates to improved apparatus for agitating the grinding elements in grinding equipment of the type shown and described in my U.S. Patent 2,764,359.
The grinding elements are substantially spherical, and all are of substantially the same size. They may be composed of metal, stone, or the like. They are put into motion and then kept in substantially constant motion out of static contact with one another by moving one or more agitator blades horizontally through a mass of them in a vessel. The improvement of this invention is in the shape of the agitator blade or blades and the improved grinding action which results from their use.
The blade is streamlined with a thin forward edge which tapers to a blunt rear edge, its cross section being substantially that of the vertical cross section of a tear drop. It is moved through the grinding elements in the direction opposite to that in which an airfoil moves through the air because the airfoil is shaped to cause minimum agitation of the air, particularly at its rear edge, and it is the function of the agitator blade to cause maximum agitation of the grinding elements, with minimum consumption of energy.
The invention will be further described in connection with the accompanying drawings, in which FIG. 1 is an elevation of an empty grinding vessel equipped with an agitator provided with blades of the invention;
FIG. 2 is an enlarged detail of a corner of the vessel, the grinding elements being much closer together than illustrated, in actual practice; and
FIG. 3 is a section through a blade on the line 33 of FIG. 2, with a schematic showing of how the grinding elements are agitated.
The vessel 5, of S-gallon capacity, contains a large number of steel balls 6, each measuring inch in diameter. The grinding elements may vary in size from fine sandsized particles, e.g. inch in diameter to elements ii; inch in diameter or larger, depending upon the size of the vessel, the nature of the material to be ground, etc. The vessel is filled with these elements to a depth to cover the top blade of the agitator.
The agitator comprises a number of evenly spaced agitator blades 8 which project from the vertical shaft 9 which is adapted to be rotated at a speed of 50 to 300 revolutions per minute, depending upon the material subjected to treatment, the ultimate particle size desired, etc. The outer ends of the blades are spaced about inch (three times an element diameter) from the wall of the vessel to prevent jamming of the elements in that space.
The agitator may be used for dry grinding, or the grinding of a suspension from which the grinding elements quickly settle. It may be used for grinding extremely hard materials, and the rapid grinding of softer materials, and the processing of sensitive materials such as biological preparations, medicinals, and other edible products in which more than a trace of impurities derived from the wall structure of the grinding vessel is objectionable. Thus, it may be used for grinding tungsten carbide, paint pigments, coal, procain penicillin and many, many other materials. Where suitable they may be ground dry, although usually they will be ground in suspension in water or other thinly fluid liquid. The hardness, etc. required in the grinding elements will depend upon the material subjected to treatment. Vessels of several hundred gallons capacity can be used. Several agitators of the type shown, all rotated in the same direction, may be used in a single vessel.
In grinding, the agitator arm is moved with the thin edge forward at a suflicient speed to keep the elements (except those adjacent the bottom and the wall of the vessel) out of static contact with one another. They are suspended in the liquid, and are directed toward each other due to the negative hydrostatic pressure caused by different sides of the same airfoil-shape agitator means. They are in substantially constant motion throughout the grinding operation, bouncing against one another and grinding the material in their respective paths. The action of the elements is more particularly described in said U.S. 2,764,359.
After grinding, the vessel may be tipped to empty its contents, or it may be provided with suitable valve means 10, which may be of the type described in said U.S. 2,764,- 359 which retains the grinding elements in the vessel while permitting the discharge of a liquid suspension or" the ground product.
The invention is covered in the claims which follow.
What I claim is:
1. In apparatus for grinding a solid in a liquid which includes in a vessel, many substantially spherical grinding elements all of substantially the same size, and at least one substantially horizontal elongated element adapted to be rotated about an axis at sufiicient speed for maintaining the grinding element out of static contact with one another, the improvement in which said elongated element is streamlined and has a cross section substantially that of the vertical cross section of a tear drop, with means for moving the elongated element with the thin edge thereof the leading edge, whereby agitation of grinding elements is accelerated immediately to the rear of the elongated element as it is moved through the grinding elements.
2. In the method of grinding by a mass of substantially spherical grinding elements all of substantially the same size which are maintained in substantially constant motion out of static contact with one another in the presence of the material to be ground, by moving therethrough streamlined agitating means which has a cross section substantially that of the vertical cross section of a tear drop, the improvement in which the thin forward edge of the agitating means is moved into the mass of agitating elements as the leading edge thereby spreading a path for the agitating means and following this the blunt edge is moved through the agitating mass whereby violent agitation of the grinding elements is produced immediately to its rear.
3. In the method of grinding by a mass of substantially spherical grinding elements all of substantially the same size and suspended in a liquid, the improvement which comprises moving through the elements streamlined agitating means which has a cross section substantially that of the vertical cross section of a tear drop, with its thin edge forward and by the subsequent passage of the blunt edge through the agitating elements directing them toward one another at the rear of the agitating means as it is moved through the liquid due to the negative hydrostatic pressure caused by the passage of the different sides of the same agitating means through the liquid, and moving the agitating means at a sufficient speed to maintain the grinding elements out of static contact with one another.
4. A grinding or mixing process performed by contacting balls or grinding elements which are part of a liquid system, whereby these elements are moved into contact primarily by producing hydrodynamic flow behind a moving streamlined agitator arm which broadens gradually backwardly from a pointed front edge and has a blunt 7 rear, thereby keeping the elements in substantially constreamlined agitator arm which has a thin forward edge and tapers backwardly to a blunt rear edge, through grinding elements out of static contact with one another in a medium that behaves like a liquid whereby the elements are moved into contact behind the agitator arm primarily because of hydrodynamic flow existing behind the agitator arm and produced by the movement of the agitator arm and thereby kept in substantially constant motion out of static contact with one another.
6. In apparatus for grinding a solid in a liquid which includes a vessel, a liquid in the vessel, many substantially spherical grinding elements all of substantially the same size suspended in the liquid out of static contact with one another, and at least one substantially horizontal elongated element adapted to be rotated about a'ver tical axis for maintaining the grinding elements suspended in the liquid, the improvement in which said elongated element has a cross section substantially that of a tear drop with the thin edge thereof the leading edge and free of all sharp edges to the rear of said leading edge, whereby agitation of the grinding elements is accelerated immediately to the rear of the elongated element primarily by hydrodynamic fiow as the elongated element is moved 10 through the grinding elements.
References Cited in the file of this patent UNITED STATES PATENTS 2,764,359 Szegvari Sept; 25, 1956 15 2,779,752 Vining Jan. 29, 1957 FOREIGN PATENTS 5 1 450,670 Canada Aug. 24, 1948

Claims (1)

  1. 2. IN THE METHOD OF GRINDING BY A MASS OF SUBSTANTIALLY SPHERICAL GRINDING ELEMENTS ALL OF SUBSTANTIALLY THE SAME SIZE WHICH ARE MAINTAINED IN SUBSTANTIALLY CONSTANT MOTION OUT OF STATIC CONTACT WITH ONE ANOTHER IN THE PRESENCE OF THE MATERIAL TO BE GROUND, BY MOVING THERETHROUGH STREAMLINED AGITATING MEANS WHICH HAS A CROSS SECTION SUBSTANTIALLY THAT OF THE VERTICAL CROSS SECTION OF A TEAR DROP, THE IMPROVEMENT IN WHICH THE THIN FORWARD EDGE OF THE AGITATING MEANS IS MOVED INTO THE MASS OF AGITATING ELEMENTS AS THE LEADING EDGE THEREBY SPREADING A PATH FOR THE AGITATING MEANS AND FOLLOWING THIS THE BLUNT EDGE IS MOVED THROUGH THE AGITATING MASS WHEREBY VIOLENT AGITATION OF THE GRINDING ELEMENTS IS PRODUCED IMMEDIATELY TO ITS REAR.
US132057A 1960-09-05 1961-08-17 Method of and apparatus for grinding a solid in a liquid Expired - Lifetime US3131875A (en)

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Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3367584A (en) * 1965-06-09 1968-02-06 Owatonna Mfg Company Inc Hammer for hammer mills
US3944144A (en) * 1973-06-13 1976-03-16 Dai Nippon Toryo Co., Ltd. Method and apparatus for dispersing suspensions
US4844355A (en) * 1987-11-05 1989-07-04 Gte Products Corporation Apparatus for milling metal powder to produce high bulk density fine metal powders
CN101402062B (en) * 2008-11-14 2010-11-10 昆明理工大学 Vertical coaxial anticentripetal grinder
WO2013167851A1 (en) 2012-05-10 2013-11-14 Belmonte Investments Limited Attritor mill and process for using it
GB202110426D0 (en) 2021-07-20 2021-09-01 Cellucomp Ltd Biodegradable and reusable cellulosic microporous superabsorbent materials
GB202110423D0 (en) 2021-07-20 2021-09-01 Cellucomp Ltd Cellulosic microporous superabsorbent materials with tunable morphology
WO2023001909A1 (en) 2021-07-20 2023-01-26 Cellucomp Limited Water absorbing and antimicrobial fabric composition
WO2023001911A1 (en) 2021-07-20 2023-01-26 Cellucomp Limited Biodegradable and reusable cellulosic microporous superabsorbent materials
WO2023078904A1 (en) 2021-11-02 2023-05-11 Cellucomp Limited Citric acid-catalysed curran modified card board materials

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1248442B (en) * 1964-02-27 1967-08-24 Draiswerke Gmbh Agitator mill for the production of solid dispersions in liquids
DE1288890B (en) * 1964-04-10 1969-02-06 Draiswerke Gmbh Method and device for the dry fine comminution of solids
DE1247822B (en) * 1965-06-24 1967-08-17 Robert Wakefield Norris Jr Agitator mill
GB9214387D0 (en) * 1992-07-07 1992-08-19 Forrest Joseph M Bead mill

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CA450670A (en) * 1948-08-24 Illitch Klock Peter Method and apparatus for treating particles of materials
US2764359A (en) * 1950-05-24 1956-09-25 Szegvari Andrew Treatment of liquid systems and apparatus therefor
US2779752A (en) * 1953-11-18 1957-01-29 Du Pont Apparatus for chemical reactions passing through viscous phase

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CA450670A (en) * 1948-08-24 Illitch Klock Peter Method and apparatus for treating particles of materials
US2764359A (en) * 1950-05-24 1956-09-25 Szegvari Andrew Treatment of liquid systems and apparatus therefor
US2779752A (en) * 1953-11-18 1957-01-29 Du Pont Apparatus for chemical reactions passing through viscous phase

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3367584A (en) * 1965-06-09 1968-02-06 Owatonna Mfg Company Inc Hammer for hammer mills
US3944144A (en) * 1973-06-13 1976-03-16 Dai Nippon Toryo Co., Ltd. Method and apparatus for dispersing suspensions
US4844355A (en) * 1987-11-05 1989-07-04 Gte Products Corporation Apparatus for milling metal powder to produce high bulk density fine metal powders
CN101402062B (en) * 2008-11-14 2010-11-10 昆明理工大学 Vertical coaxial anticentripetal grinder
WO2013167851A1 (en) 2012-05-10 2013-11-14 Belmonte Investments Limited Attritor mill and process for using it
GB202110426D0 (en) 2021-07-20 2021-09-01 Cellucomp Ltd Biodegradable and reusable cellulosic microporous superabsorbent materials
GB202110423D0 (en) 2021-07-20 2021-09-01 Cellucomp Ltd Cellulosic microporous superabsorbent materials with tunable morphology
GB2609039A (en) 2021-07-20 2023-01-25 Cellucomp Ltd Cellulosic microporous superabsorbent materials with tunable morphology
GB2609040A (en) 2021-07-20 2023-01-25 Cellucomp Ltd Biodegradable and reusable cellulosic microporous superabsorbent materials
WO2023001909A1 (en) 2021-07-20 2023-01-26 Cellucomp Limited Water absorbing and antimicrobial fabric composition
WO2023001911A1 (en) 2021-07-20 2023-01-26 Cellucomp Limited Biodegradable and reusable cellulosic microporous superabsorbent materials
WO2023078904A1 (en) 2021-11-02 2023-05-11 Cellucomp Limited Citric acid-catalysed curran modified card board materials

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CH393884A (en) 1965-06-15
GB1000459A (en) 1965-08-04
DE1164215B (en) 1964-02-27
NL110346C (en)

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