US3539116A - Vibratory grinding - Google Patents
Vibratory grinding Download PDFInfo
- Publication number
- US3539116A US3539116A US654209A US3539116DA US3539116A US 3539116 A US3539116 A US 3539116A US 654209 A US654209 A US 654209A US 3539116D A US3539116D A US 3539116DA US 3539116 A US3539116 A US 3539116A
- Authority
- US
- United States
- Prior art keywords
- pulsator
- grinding
- media
- chamber
- mill
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B02—CRUSHING, PULVERISING, OR DISINTEGRATING; PREPARATORY TREATMENT OF GRAIN FOR MILLING
- B02C—CRUSHING, PULVERISING, OR DISINTEGRATING IN GENERAL; MILLING GRAIN
- B02C19/00—Other disintegrating devices or methods
- B02C19/16—Mills provided with vibrators
-
- 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
- B02C17/14—Mills in which the charge to be ground is turned over by movements of the container other than by rotating, e.g. by swinging, vibrating, tilting
Definitions
- a fixed grinding chamber has an electric motor mounted over it driving a shaft extending vertically downwards'and to the shaft a pulsator is connected, by means of a flexible coupling, so that the pulsator is rotated and by means of outof-balance weights carried by it imparts ahigh frequency low amplitude vibration to the mass of grinding media and material to be processed in the chamber.
- Mills are also known in which the grinding media is stirred or caused to move at random by the action of rotating blades within the media and charge. Mills of the first type, in general, grind efficiently by producing high frequency impacts, while mills of the second type prove effective (by virtue of high shear forces) for dispersing powders in liquids.
- the object of the present invention is to produce an improved form of vibration mill which will facilitate the production of both high frequency impact and shear forces.
- a charge of material to be processed is fed into a grinding chamber containing grinding media, the chamber being maintained in a static position, and the charge and media are then subjected to a high frequency low-amplitude high frequency by the action of a pulsator extending into the material.
- a vibration mill is provided with a grinding chamber which is maintained in a static position and a pulsator which extends into the chamber and is operated to set up a high frequency vibration of the material being processed.
- the pulsator is in the form of a single out-of-balance device located on the centre vertical axis of the grinding chamber and depending into the part of the chamber which will in use be occupied by the grinding media and charge of material.
- the pulsator is capable of causing the entire mass of material in the chamber to vibrate through an amplitude of not less than one one-thousandth inch and not more than onehalf inch but these limits may be inapplicable in particular cases.
- the amplitude is governed mainly by the design of the pulsator and speed at which it is operated.
- FIG. 1 is a sectional elevation of a mill and associated equipment.
- FIG. 2 is a section through a pulsator unit and FIG. 3 a plan thereof.
- FIG. 4 is a plan of an alternative form of pulsator.
- FIGS. 2, 3 and 4 are drawn to a larger scale than FIG. 1.
- An electric motor is mounted centrally over a grinding chamber 11, the axis of the motor represented by its output shaft 10a and the axis of the chamber being vertical.
- the pulsator as shown in FIG. I is in the form of a circular hollow housing closed at the bottom and carried by a central shaft 16. This shaft is rapidly rotated by means of the motor 10 and universal joint coupling 19, and an out-of-balance weight causing the lower end of the housing 15 to vibrate through one cycle for each rotation so that in this case a 1,500 revolutions per minute motor will produce vibrations of 1,500 cycles per minute.
- the deflection is controlled by springs 17 mounted between plates 18 cam'ed by the shaft 16.
- This circular form of rotator produces a low starting torque, and wear on the pulsator is approximately uniform all round so that the working life is long. It is found advantageous to connect the motor shaft 10a to the pulsator shaft 16 through a flexible coupling. The work done isrelated to the revolutions per minute of the pulsator and the moment of inertia of the out-of-balance weight. Hence, by using a variable speed motor a wide range of grinding conditions can be produced.
- the housing 15 carries a tubular enclosure 20 on its inside wall, closed at the bottom by a welded plug 21.
- weights 22 are inserted and the space above them is filled up by tubular distance pieces 23.
- the enclosure '20 is fixed in the top cover 24 of the housing 15 and its contained weights and distance pieces are held in place by a plug 25 having a square or similar upstanding boss 26 by means of which the plug can be screwed tightly into the enclosure 20.
- the shaft 16 fits into a hole in the cover 24 and is welded in position, a collar 27 being fitted round it.
- the housing 15 is of elliptical cross section, the enclosure 20 and weights 21 being omitted.
- the housing is rotated on the approximately vertical axis by the electric motor 10.
- the difference between the major and minor axes of the cross section of the pulsator determines the amplitude of the vibration applied to the grinding media which is in contact with the surface of the pulsator.
- the vibrational energy is then transmitted to adjacent pieces of media so causing a rapid succession of grinding impacts upon the charge material located in the interstices between the media.
- the rotary movement of the pulsator produces high shear forces in the media and between the surface of the pulsator and the adjacent media and hence such an arrangement will provide very effective fine grinding and in addition will disperse the products in the liquid present.
- Pulsator systems as described in either of the foregoing examples can maintain large quantities of media in a state of vibration.
- the most suitable shape for the grinding chamber is approximately cylindrical arranged symmetrically about the pulsator; the bottom of the pulsator being approximately 4 inches above the base of the grinding chamber.
- the chamber 11 may, however,
- the housing 15 also preferably has a domed lower end 1511. Material to be processed is delivered into a feed and recirculation tank 36. Circulation is maintained by a pump 37 through pipes 38 controlled by valves 39, the chamber having a central discharge grid 40 at the base. The distance from the axis of the pulsator to the vertical wall of the grinding chamber is dependent upon the distance through the media that vibrational energy can effectively be transmitted and this in turn depends upon the type of grinding media, the nature of the charge material and the amplitude of the pulsator.
- the particular pulsators described tend to set up compound vibrations in the media and charge. Obviously as the pulsator moves outwards radially there will bean outward and inward movement of the material in a substantially horizontal plane. Since the lower end of the pulsator will have a greater displacement than the higher portion nearer the coupling, there will also be a vertical component in the movement of the material. The resultant compound vibration has been found to be of great value -in promoting efficient and expeditious processing of the material.
- This system of grinding is equally effective for both dry and wet processing.
- batch processing it is merely necessary to charge the mill by way of the pipe 38 and after grinding for the requisite time to discharge through the grid 40 at the base, the apertures of the grid being large enough to pass the ground product but sufficiently small to retain the grinding media.
- the mill can also be operated continuously by introducing raw material at the top and removing the ground product at the base.
- the slurry can be pumped in at the base and the ground product removed by overflow discharge; in this case a certain amount of classification is achieved particularly if the upper surface of the grinding media is a few inches below the surface of the slurry.
- Continuous dry grinding can also be effected by air sweeping the upper part of the grinding chamber.
- the thin layer of liquid (in wet processes) or gas (in dry processes) carried round on the surface of the pulsator tends to produce a zone comparatively free from media and this reduces the frictional contact and pressure between the rotating pulsator and the media, the direct result being a considerable reduction in rate of wear on the pulsator.
- the lining of the grinding chamber can be fabricated from a wide variety of materials according to the particular type of product.
- Manganese steel, stainless steel, or steel covered by rubber are suitable for most applications but at as the grinding chamber is completely static, it is possible to use virtually any type of lining including ceramic blocks.
- the pulsator can be fabricated from various types of steel, steel rubber covered or steel fitted with a ceramic sleeve. The latter, in conjunction with a ceramic lining, gives a mill admirably suited to the grinding of materials which are required to be free from all traces of metallic impurity. Such a mill is, for example, most effective for the processing of white paints.
- the choice of grinding media will depend largely upon the particular process. In general, the composition of the grinding media should be such as to provide no disadvantages if introduced in very small quantity to the product.
- the media should have very high abrasion resistance and be capable of taking a high polish to give a smooth surface free from indentations. For most applications where both impact and shear forces are desirable the media should be spherical, or near spherical.
- the size of the media will vary according to the size of the material being processed and to the size of the mill but one-half inch or less diameter spheres are found suitable for most applications. Where a very large range of size reduction is required, it is advantageous to use media graded in size. Sand granules or glass ballotini may also be used.
- a vibratory grinding mill having a grinding chamber which is maintained in a static position, a bed of grinding media and material to be processed in said chamber, an elongate pulsator extending into the chamber so that its outer surface is in contact with said bed, and means for rotating said pulsator about an axis extending longitudinally thereof for simultaneously sweeping said outer surface of the pulsator past the material of the bed in contact therewith to produce shear forces in said bed and displacing the bed back and forth generally radially' of said pulsator to produce high frequency, low amplitude grinding impact movement of said bed.
- a mill as claimed in claim 1 having the pulsator located upon a central vertical axis inthe grinding chamber.
- a mill as claimed in claim 2 in which the pulsator comprises a central shaft, a housing attached to the shaft, an enclosure attached to the housing and off centre with respect to the shaft, and weights contained in the enclosure.
- a mill as claimed in claim 1 having an electric motor mounted centrally above the grinding chamber, a shaft driven by and depending vertically from the motor, and a flexible coupling including deflection control springs connecting the shaft with the pulsator.
- a mill as claimed in claim 1 having a grinding chamber of frustoconical form, wider at the base, and having the base internally concave to facilitate central discharge therefrom, and a central grid in the said base for that purpose.
- a vibratory grinding mill comprising, in combination:
- a vertically elongate pulsator having a longitudinal axis and projecting into said receptacle, said pulsator having an outer surface substantially smaller than said chamber and positioned therein to define a region around said outer surface between the outer surface of said pulsator and the inner surface of said receptacle for receiving grinding media;
- said pulsator adapted to displace a volume in said chamber in response to rotation of said pulsator about said axis which volume is greater than the volume of the buried portion of said pulsator and to this impart inward and outward grinding impact movement to said media;
- the vibratory grinding mill according to claim 8 including a flexible coupling connecting the upper end of said pulsator to said means whereby to allow the pulsator to cone therebelow.
Landscapes
- Engineering & Computer Science (AREA)
- Food Science & Technology (AREA)
- Crushing And Grinding (AREA)
- Finish Polishing, Edge Sharpening, And Grinding By Specific Grinding Devices (AREA)
- Disintegrating Or Milling (AREA)
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB33766/66A GB1133791A (en) | 1966-07-27 | 1966-07-27 | Improvements relating to vibratory grinding |
Publications (1)
Publication Number | Publication Date |
---|---|
US3539116A true US3539116A (en) | 1970-11-10 |
Family
ID=10357167
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US654209A Expired - Lifetime US3539116A (en) | 1966-07-27 | 1967-07-18 | Vibratory grinding |
Country Status (8)
Country | Link |
---|---|
US (1) | US3539116A (xx) |
BE (1) | BE701919A (xx) |
CH (1) | CH466009A (xx) |
DE (1) | DE1607570B1 (xx) |
ES (1) | ES343380A1 (xx) |
GB (1) | GB1133791A (xx) |
NL (1) | NL6710316A (xx) |
SE (1) | SE321876B (xx) |
Cited By (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3993254A (en) * | 1973-09-28 | 1976-11-23 | Gebruder Netzsch, Maschinenfabrik | Agitator mill |
US4288165A (en) * | 1979-08-15 | 1981-09-08 | The Hutson Corporation | Vibratory actuator incorporating hydrodynamic journal bearing |
US4387539A (en) * | 1981-03-30 | 1983-06-14 | The Hutson Corporation | Vibratory actuator |
US5460446A (en) * | 1989-05-29 | 1995-10-24 | Hospal Industrie | Device and method for preparing solution for medical use |
EP0390809B2 (de) † | 1987-12-03 | 1996-10-23 | GETZMANN, Hermann | Mahlvorrichtung |
US5918976A (en) * | 1994-09-06 | 1999-07-06 | Konica Corporation | Mixing method |
WO2000012215A1 (en) * | 1998-08-31 | 2000-03-09 | Hicom International Pty. Ltd. | Improved drive mechanism for centrifugal grinding mills |
CN104499338A (zh) * | 2014-12-18 | 2015-04-08 | 昌邑润德生态纤维有限公司 | 一种调浓罐 |
Family Cites Families (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE665655C (de) * | 1936-03-12 | 1938-09-30 | Hermann Plauson | Mahlvorrichtung |
DE678779C (de) * | 1938-03-16 | 1939-07-21 | I G Farbenindustrie Akt Ges | Schwingmuehle |
DE888641C (de) * | 1951-11-06 | 1953-09-03 | Kohlenscheidungs Ges Mit Besch | Mahlanlage mit frei beweglichen Mahlkoerpern in einem Mahlgehaeuse |
US3074786A (en) * | 1959-12-17 | 1963-01-22 | Shell Oil Co | Fluid mixer with rotating baffles and method of operating same |
-
1966
- 1966-07-27 GB GB33766/66A patent/GB1133791A/en not_active Expired
-
1967
- 1967-07-18 US US654209A patent/US3539116A/en not_active Expired - Lifetime
- 1967-07-24 ES ES343380A patent/ES343380A1/es not_active Expired
- 1967-07-24 CH CH1049867A patent/CH466009A/fr unknown
- 1967-07-25 DE DE19671607570 patent/DE1607570B1/de active Pending
- 1967-07-26 NL NL6710316A patent/NL6710316A/xx unknown
- 1967-07-27 SE SE10896/67*A patent/SE321876B/xx unknown
- 1967-07-27 BE BE701919D patent/BE701919A/xx unknown
Cited By (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3993254A (en) * | 1973-09-28 | 1976-11-23 | Gebruder Netzsch, Maschinenfabrik | Agitator mill |
US4288165A (en) * | 1979-08-15 | 1981-09-08 | The Hutson Corporation | Vibratory actuator incorporating hydrodynamic journal bearing |
US4387539A (en) * | 1981-03-30 | 1983-06-14 | The Hutson Corporation | Vibratory actuator |
EP0390809B2 (de) † | 1987-12-03 | 1996-10-23 | GETZMANN, Hermann | Mahlvorrichtung |
US5460446A (en) * | 1989-05-29 | 1995-10-24 | Hospal Industrie | Device and method for preparing solution for medical use |
US5727877A (en) * | 1989-05-29 | 1998-03-17 | Hospal Industrie | Method for preparing solutions for medical use |
US5918976A (en) * | 1994-09-06 | 1999-07-06 | Konica Corporation | Mixing method |
WO2000012215A1 (en) * | 1998-08-31 | 2000-03-09 | Hicom International Pty. Ltd. | Improved drive mechanism for centrifugal grinding mills |
CN104499338A (zh) * | 2014-12-18 | 2015-04-08 | 昌邑润德生态纤维有限公司 | 一种调浓罐 |
Also Published As
Publication number | Publication date |
---|---|
BE701919A (xx) | 1968-01-02 |
DE1607570B1 (de) | 1971-06-09 |
CH466009A (fr) | 1968-11-30 |
ES343380A1 (es) | 1968-12-01 |
SE321876B (xx) | 1970-03-16 |
NL6710316A (xx) | 1968-01-29 |
GB1133791A (en) | 1968-11-20 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US3539116A (en) | Vibratory grinding | |
US3464674A (en) | Vibrator | |
JPH0632786B2 (ja) | 振動を利用した材料の処理方法およびそのための振動発生装置 | |
US3199792A (en) | Comminuting and dispersing process and apparatus | |
US3268177A (en) | Vibro-energy mill | |
GB1486793A (en) | Separating device for separating grinding elements from a ground material in a liquid suspension in an agitating grinding mill | |
US2650033A (en) | Method and apparatus for vibratory grinding | |
CA1187849A (en) | Mass (inductive) reactance vibratory mill or crusher employing mechanical drive force | |
US2309033A (en) | Method for multifrequency vibration | |
US3087776A (en) | Washing machine and process of washing therewith | |
GB1583745A (en) | Apparatus for mixing materials | |
US3429560A (en) | Device for mixing or surfacetreating flowable goods | |
US4629135A (en) | Cycloidal sonic mill for comminuting material suspended in liquid and powdered material | |
RU2637215C1 (ru) | Вибрационная мельница | |
RU172477U1 (ru) | Шаровая мельница | |
JPS5933412B2 (ja) | 製品処理方法及び装置 | |
GB1069986A (en) | Method of comminution and apparatus therefor | |
US3596407A (en) | Sonic polishing apparatus | |
US2258059A (en) | Stone crusher | |
US20160296939A1 (en) | Continuous Grinding Device for Divided Solid Materials | |
US4201017A (en) | Methods and apparatus for the treatment of products | |
US2819849A (en) | Vibrating ball mill with greater amplitude of vibration at feed end | |
SU852354A1 (ru) | Устройство дл обработки дисперсногоМАТЕРиАлА | |
US3429512A (en) | Sonic method and apparatus for grinding rock material and the like to powder | |
US3391872A (en) | Vibrating grinding mill |