US3716196A - Method of operating an impact comminutor - Google Patents

Method of operating an impact comminutor Download PDF

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Publication number
US3716196A
US3716196A US00133973A US3716196DA US3716196A US 3716196 A US3716196 A US 3716196A US 00133973 A US00133973 A US 00133973A US 3716196D A US3716196D A US 3716196DA US 3716196 A US3716196 A US 3716196A
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United States
Prior art keywords
rotor element
fractions
comminutor
rotor
elements
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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
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US00133973A
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English (en)
Inventor
H Motek
J Jobkes
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Salzgitter Maschinenbau GmbH
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HAZEMAG GmbH
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Assigned to HAZEMAG DR. E. ANDREAS GMBH & CO. reassignment HAZEMAG DR. E. ANDREAS GMBH & CO. CHANGE OF NAME (SEE DOCUMENT FOR DETAILS). DECEMBER 18, 1972 AND MARCH 21, 1977 RESPECTIVELY, GERMANY Assignors: HAZEMAG DR. E. ANDREAS KG (CHANGED TO), HAZEMAG, HARTZERKLEINERUNGS-UND ZEMENT-MASCHINENBAU-GESELLSCHAFT MIT BESCHRANKTER HAFTUNG (CHANGED TO)
Assigned to SALZGITTER MASCHINENBAU GMBH reassignment SALZGITTER MASCHINENBAU GMBH ASSIGNMENT OF ASSIGNORS INTEREST. Assignors: HAZEMAG DR. E. ANDREAS GMBH & CO., BY: KARL W. WISSING, RECEIVER IN BAKRUPTCY
Assigned to WISSING, KARL-WILHELM, TRUSTEE IN BANKRUPTCY reassignment WISSING, KARL-WILHELM, TRUSTEE IN BANKRUPTCY COURT APPOINTMENT (SEE DOCUMENT FOR DETAILS). Assignors: HAZEMAG DR. E. ANDREAS GMBH & CO. KG, BY: THE DISTRICT COURT OF GERMANY BANKRUPT
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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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
    • B02C25/00—Control arrangements specially adapted for crushing or disintegrating
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B02—CRUSHING, PULVERISING, OR DISINTEGRATING; PREPARATORY TREATMENT OF GRAIN FOR MILLING
    • B02C—CRUSHING, PULVERISING, OR DISINTEGRATING IN GENERAL; MILLING GRAIN
    • B02C13/00—Disintegrating by mills having rotary beater elements ; Hammer mills
    • B02C13/02—Disintegrating by mills having rotary beater elements ; Hammer mills with horizontal rotor shaft
    • B02C13/06—Disintegrating by mills having rotary beater elements ; Hammer mills with horizontal rotor shaft with beaters rigidly connected to the rotor
    • B02C13/09—Disintegrating by mills having rotary beater elements ; Hammer mills with horizontal rotor shaft with beaters rigidly connected to the rotor and throwing the material against an anvil or impact plate
    • B02C13/095—Disintegrating by mills having rotary beater elements ; Hammer mills with horizontal rotor shaft with beaters rigidly connected to the rotor and throwing the material against an anvil or impact plate with an adjustable anvil or impact plate

Definitions

  • the comminuted material is then subjected to measurements to determine the proportion of a selected one of these fractions with reference to the sum of all other fractions, and the speed of rotation of the rotor element and/or the positioning of the comminuting elements with reference to one another and with reference to the rotor element are adjusted as a function of the measured value thus obtained.
  • the present invention relates generally to a comminuting method and more particularly to a method of operating an impact comminutor.
  • impact comminutors In recent years the use of so-called impact comminutors has strongly increased in all areas of comminution where the application of this type of equipment is feasible.
  • the reason for this increase in popularity of impact comminutors is that they are capable of comminuting-that is reducing from larger size to smaller sizelarge quantities of material in a relatively small and inexpensive plant.
  • the extent to which the materials are comminuted and reduced in size, is substantially better than if the same materials were comminuted in the heretofore common machines, such as jawbreaker or rotary crusher machines.
  • the comminution of the material is primarily effected by the contact portions or impact bars provided on the single or several rotors which rotate within the machine, in conjunction with the break-up plates or rebound plates.
  • the material contacts the rotating rotor or rotors and is flung off the same against the breakup plates.
  • the wear in such apparatus is primarily concentrated on the contact or impact portions mounted on the rotors, because they are of relatively small size so that their configuration and size changes relatively rapidly due to wear resulting from constant contact with the material being comminuted. This makes it necessary to exchange these contact portions relatively rapidly.
  • the comminuting circumstances also change after a relatively brief operating time due to a rounding of the edges of the contact portions, again resulting from wear, and the circular area surrounding the circumference of the rotor and within which material is contacted by the contact portions projecting from the circumference of the rotor, varies-that is increases as the materal of the contact portions wears away-so that the circumferential speed of the edges on the contact portions on the rotor-which is determinative for the proper comminution-should also vary concomitantly with the wear.
  • a concomitant object of the invention is to provide such an improved method which assures that the initially selected degree of comminution-that is size and width of different fractions in the comminuted material-will be automatically maintained at all times.
  • one features of the present invention resides in a method of operating an impact comminutor having a rotor element and movable comminuting elements mounted outwardly and circumferentially spaced about the rotor element.
  • the novel method comprises, briefly stated, the steps of admitting material to be comminuted into the comminutor so as to undergo comminution into larger and smaller portions prior to leaving the comminutor.
  • the proportion of one of the fractions with reference to the sum of all other fractions in a quantity of comminuted material is measured, and at least one of the elements is adjusted with reference to the other element or elements as a function of the thus-measured value.
  • the variation of several values influencing the degree of comminution may be preselected in its sequence and in its relationship by suitable electronically controlled sequencing means.
  • Contactless (i.e. non-contact-making) sensors may limit the maximum displacement of the various movable elements, particularly with reference to their approach towards the circumference of the rotor or rotors.
  • FIGURE is a somewhat diagrammatic side-elevational view, illustrating an impact comminutor whose operation is to be controlled in accordance with the present method.
  • the comminutor has a housing 1 and in this embodiment a single rotor 2, which is provided on its circumference with the contact portions 3 which may be in form of strip-shaped elements or the like. In any case,
  • the rotor 2 is driven in rotation by a suitable electromotor for instance via a continuously variable gear drive 5.
  • a plurality of breaker plates 6 Mounted about the rotor circumferentially and radially spaced therefrom is a plurality of breaker plates 6. However, a single such breaker plate could also be utilized. In any case, in the illustrated embodiment the lower edges of the breaker plate 6 define with the circle 4 a gap a. In order to obtain certain grain configurations it is also possible to provide a so-called grinding path 8 which surrounds a portion of the circumference of the rotor 2 and may be configurated as a grate or the like, if desired. This is already known. For the positioning of the element 8 the gap b between the element 8 and the circle 4 is determinative.
  • the breaker plates 6 and the element 8, if the latter is provided as in the illustrated embodiment, can be displaced with reference to the rotor 2 by means of hydraulic cylinders 7 which need not be discussed or described in more detail because they are entirely conventional.
  • the material to be comminuted is introduced in known manner via a conveying device 10 into the inlet 11 of the impact comminutor, and after being comminuted leaves the comminutor through the outlet 12.
  • a diverting member 12' is provided which periodically acts to divert a portion of the comminuted material onto a screen 13 which may be so constructed as to have several layers of different mesh superimposed one upon the other.
  • weighing devices 14 and 15 such as scales, which act upon an indicating device 16 coupled with them and which indicates the difference of the quantities of comminuted material received by the devices 14 and 15, respectively. It will be clear that the construction of the screen 13 is such that a fraction of a certain grain size is permitted to go to one of the weighing devices (either 14 or 15) whereas the remaining fractions go to the respectively other weighing device.
  • the proportion of the preselected single fraction which serves as an indicator of the degree of comminution to the sum of the remaining fractions is determined by comparing the weights, and the result may be utilized either in form of an electronic value or a hydraulic impulse and be forwarded via the hydraulic unit 9or a suitable electric unit which may be used in its place-to the gear drive 5 or to the hydraulic cylinders 7.
  • the measured value will be used to vary the speed of rotation of the rotor 2 and/or to displace the components 6 and/or 8 with reference to the rotor 2. This serves to maintain the degree of comminution constant in that it automatically compensates for wear of the portions 3.
  • the indicator device 16 constantly provides an indication of the proportion of the selected fraction with reference to the total quantity of comminuted material. It is well known that this value-given the same machine and the same mix of material entering through the inlet 1lis determinative of the total grain size composition ofthe comminuted material.
  • the indicator device 16 may act directly or via a proportionately variable small electromotor upon a switching device of the type which is for instance available under the designations BSW 499, BSW 502 and BSW 496 from the Balluff KG of Neuhausen, Germany.
  • a switching device may be incorporated in unit 9 and utilizes adjustable cams which can be set to preselect the sequence and time intervals at which changes in the operation and/or position of the elements 5, 6 and 8 are to take place.
  • the cams act upon limit switches which in turn act upon a hydraulic device forming part of unit 9 and which may be of the type available from the E. A. Storz K.G. of Tuttlingen, Germany.
  • control of elements 5, 6 and 8 can also be effected completely electrically, i.e. without the hydraulic device.
  • the signals from the limit switches are supplied via known relays to electromotors having axially displaceable spindles, such as are available under the designation Elektro-Zylinder from the Raco-Elektro-mill GmbH of Schwelm, Germany, and which replace the elements 7.
  • the devices l4, l5 and 16 measure simultaneously the two separate material quantities which they respectively receive, namely the preselected fraction and the remaining fraction of the quantity of comminuted material which is diverted to them by the component 12. These measurements are compared with one another and the result obtained. Via electronic or electrical impulses the thus obtained value acts upon the device 9 which in accordance with a preset value controls the operation and/or positioning of the drive 5, the components 6, and the device 8 in preselected sequence.
  • the scales or weighing devices 14 and 15 in the illustrated embodiment are in form of two guide members which are journalled and which, depending upon the weight acting upon them, will because displaced to different extents from their normal rest position, thereby exerting pressure upon balancing weights, springs or other elements provided for this purpose. They can be replaced, however, with other devices, for instance with conveyortype scales, such as manufactured by the Haasler GmbH of Lengereich, Germany.
  • the device 9 is a hydraulic unit including electrically controlled hydraulic valves which are controlled by the impulses derived from the devices 14, 15 and 16 and in accordance with this control supply oil to the devices 5 and 7 via a nonillustrated hydraulic pump.
  • a method of operating an impact comminutor having a rotor element rotatable at variable rates of speed which can be increased, and comminuting elements mounted circumferentially spaced about the rotor element and whose positions relative to said rotor element can be varied, both in response to wearingaway of the respective elements, comprising the steps of admitting material to be comminuted into said comminutor so as to undergo comminution into larger and smaller fractions prior to leaving said comminutor; measuring the proportions of one of said fractions to the sum of all of said fractions in a quantity of comminuted material; and compensating for wearing-away of the respective elements by at least increasing the rate of speed of said rotor element as a function of the thus-measured value.
  • step of compensating further comprises displacing at least one of said comminuting elements with reference to the circumference of said rotor element.
  • step of compensating further comprises displacing said comminuting elements simultaneously with reference to the circumference of said rotor element as well as with reference to one another.
  • step of compensating comprises displacing said comminuting elements sequentially with reference to the circumference of said rotor element as well as with reference to one another.
  • said comminuting elements being movable towards and away from the circumference of said rotor element; and further comprising the step of sensing the approach of comminuting elements being displaced toward said rotor element, and limiting such approach to a predetermined distance from said rotor element.
  • step of sensing comprises contactless sensing.
  • step of measuring comprises weighing said one fraction and weighing all others of said fractions separate from said one fraction.
  • step of measuring further comprises comparing the weight of said one fraction with the weight of all others of said fractions.

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  • Engineering & Computer Science (AREA)
  • Food Science & Technology (AREA)
  • Crushing And Pulverization Processes (AREA)
  • Crushing And Grinding (AREA)
US00133973A 1970-04-17 1971-04-14 Method of operating an impact comminutor Expired - Lifetime US3716196A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DE19702018496 DE2018496A1 (de) 1970-04-17 1970-04-17 Verfahren zum Betrieb einer Prallmühle

Publications (1)

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US3716196A true US3716196A (en) 1973-02-13

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US00133973A Expired - Lifetime US3716196A (en) 1970-04-17 1971-04-14 Method of operating an impact comminutor

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US (1) US3716196A (de)
AT (1) AT327657B (de)
CA (1) CA934350A (de)
DE (1) DE2018496A1 (de)
FR (1) FR2092338A5 (de)
GB (1) GB1343810A (de)

Cited By (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4645131A (en) * 1984-12-24 1987-02-24 Hailey Robert W Powder milling method to produce fine powder sizes
US4881689A (en) * 1985-03-15 1989-11-21 Gebrueder Buehler Ag Method for setting the grinding rollers in roller frames of a flour milling plant, as well as flour milling plant for performing the method
US5226604A (en) * 1989-04-07 1993-07-13 Salzgitter Maschinenbau Gmbh Method of and apparatus for adjusting comminuting machines
US5269469A (en) * 1990-11-13 1993-12-14 Buhler Ag Method for measuring the fineness or bulk density, apparatus for carrying out the method and control system with such an apparatus
USRE34946E (en) * 1987-05-05 1995-05-23 New Holland North America, Inc. Method and apparatus for adjusting a shear bar relative to a cutter head
US5482218A (en) * 1993-10-20 1996-01-09 Ha; Yonggan Rock crushing apparatus and method
US5975443A (en) * 1996-08-08 1999-11-02 Hundt; Vincent G. Waste recycling device
US6012661A (en) * 1996-05-02 2000-01-11 Braibanti Golfetto S.P.A. Method for automatically controlling grinding within a milling plant, and plant for implementing the method
US20030029562A1 (en) * 2000-11-16 2003-02-13 Mikio Yotsumoto Foam resin, method of collecting foam gas, and method of disassembling refrigerator
WO2004002630A1 (en) * 2002-06-26 2004-01-08 Van Der Zanden, Rosemarie, Johanna Structural composite accelerator member
US20040103514A1 (en) * 2000-07-14 2004-06-03 Matsushita Electric Industrial Co., Ltd. Method for disassembling refrigerator, compressing device, and device for disassembling the same
EP2021763A1 (de) * 2006-05-18 2009-02-11 The University Of Queensland Vorrichtung zur bestimmung der brucheigenschaften von partikulärem material
WO2014187824A1 (en) * 2013-05-21 2014-11-27 Flsmidth A/S Methods and apparatus for the continuous monitoring of wear in grinding circuits
WO2020198647A1 (en) * 2019-03-27 2020-10-01 Sgs North America Inc. Device for test milling an ore sample
US10960400B2 (en) * 2017-04-26 2021-03-30 Kolberg-Pioneer, Inc. Apparatus and method for an apron return assembly

Families Citing this family (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4084752A (en) * 1975-12-11 1978-04-18 Kawasaki Jukogyo Kabushiki Kaisha Gap adjusting system for crusher and method
DK146418C (da) * 1981-01-19 1984-03-12 Phoenix Tagpag Doseringsgranulator specielt til granulering af et hoejviskost materiale, isaer genbrugsasfalt
DE3911086C2 (de) * 1988-10-10 1994-10-20 Gronholz Claus Prallbrecher
DE3911271A1 (de) * 1989-04-07 1990-10-11 Salzgitter Maschinenbau Verfahren zum betrieb einer zerkleinerungsmaschine und anlage zur automatischen einstellung der zerkleinerungsmaschine
DE4116134A1 (de) * 1991-05-17 1992-11-19 Orenstein & Koppel Ag Prallbrecher und verfahren zum einstellen des arbeitsspaltes
DE4409037C2 (de) * 1994-03-17 1997-05-15 Umwelt Technics Nord Gmbh Verfahren zum Betrieb eines Prallbrechers und Meßmittel zur Durchführung des Verfahrens
DE19511097C1 (de) * 1995-03-25 1996-07-11 Krupp Foerdertechnik Gmbh Verfahren zur automatischen Einstellung des Mahlspaltes einer Zerkleinerungsmaschine und Zerkleinerungsmaschine
AT523805B1 (de) * 2020-05-13 2022-09-15 Rubble Master Hmh Gmbh Verfahren zur Verschleißerkennung bei Brechern in Leerfahrt
CN114700146B (zh) * 2021-07-02 2023-09-01 淮北矿业股份有限公司 一种两段式智能煤泥破碎机及煤泥智能破碎方法

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2287799A (en) * 1939-06-13 1942-06-30 Stanley D Hartshorn Hammer mill
US2767929A (en) * 1952-08-08 1956-10-23 Bath Iron Works Corp Reversible hammermill with adjustable upper breaker blocks
US3568938A (en) * 1967-05-31 1971-03-09 Babbitless Sa Controlling the granulometry of material

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2287799A (en) * 1939-06-13 1942-06-30 Stanley D Hartshorn Hammer mill
US2767929A (en) * 1952-08-08 1956-10-23 Bath Iron Works Corp Reversible hammermill with adjustable upper breaker blocks
US3568938A (en) * 1967-05-31 1971-03-09 Babbitless Sa Controlling the granulometry of material

Cited By (25)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4645131A (en) * 1984-12-24 1987-02-24 Hailey Robert W Powder milling method to produce fine powder sizes
US4881689A (en) * 1985-03-15 1989-11-21 Gebrueder Buehler Ag Method for setting the grinding rollers in roller frames of a flour milling plant, as well as flour milling plant for performing the method
USRE34946E (en) * 1987-05-05 1995-05-23 New Holland North America, Inc. Method and apparatus for adjusting a shear bar relative to a cutter head
US5226604A (en) * 1989-04-07 1993-07-13 Salzgitter Maschinenbau Gmbh Method of and apparatus for adjusting comminuting machines
US5269469A (en) * 1990-11-13 1993-12-14 Buhler Ag Method for measuring the fineness or bulk density, apparatus for carrying out the method and control system with such an apparatus
US5407138A (en) * 1990-11-13 1995-04-18 Buhler Ag Method for measuring the fineness or bulk density, apparatus for carrying out the method and control system with such an apparatus
US5482218A (en) * 1993-10-20 1996-01-09 Ha; Yonggan Rock crushing apparatus and method
US6012661A (en) * 1996-05-02 2000-01-11 Braibanti Golfetto S.P.A. Method for automatically controlling grinding within a milling plant, and plant for implementing the method
US5975443A (en) * 1996-08-08 1999-11-02 Hundt; Vincent G. Waste recycling device
US20040103514A1 (en) * 2000-07-14 2004-06-03 Matsushita Electric Industrial Co., Ltd. Method for disassembling refrigerator, compressing device, and device for disassembling the same
US6944926B2 (en) * 2000-07-14 2005-09-20 Matsushita Electric Industrial Co., Ltd. Method for disassembling refrigerator, compressing device, and device for disassembling the same
US6938318B2 (en) 2000-11-16 2005-09-06 Matsushita Electric Industrial Co., Ltd. Method for collecting a foam resin from a housing of a refrigerator
US20030029562A1 (en) * 2000-11-16 2003-02-13 Mikio Yotsumoto Foam resin, method of collecting foam gas, and method of disassembling refrigerator
WO2004002630A1 (en) * 2002-06-26 2004-01-08 Van Der Zanden, Rosemarie, Johanna Structural composite accelerator member
EP2021763A1 (de) * 2006-05-18 2009-02-11 The University Of Queensland Vorrichtung zur bestimmung der brucheigenschaften von partikulärem material
US20090199625A1 (en) * 2006-05-18 2009-08-13 The University Of Queensland Apparatus for Determining Breakage Properties of Particulate Material
EP2021763A4 (de) * 2006-05-18 2010-04-07 Univ Queensland Vorrichtung zur bestimmung der brucheigenschaften von partikulärem material
US8272247B2 (en) 2006-05-18 2012-09-25 The University Of Queensland Apparatus for determining breakage properties of particulate material
WO2014187824A1 (en) * 2013-05-21 2014-11-27 Flsmidth A/S Methods and apparatus for the continuous monitoring of wear in grinding circuits
CN105592927A (zh) * 2013-05-21 2016-05-18 Fl史密斯公司 用于持续监测研磨回路中的磨损的方法和装置
CN105592927B (zh) * 2013-05-21 2018-04-27 Fl史密斯公司 用于持续监测研磨回路中的磨损的方法和装置
EA032648B1 (ru) * 2013-05-21 2019-06-28 Эф-Эл-Смидт А/С Система и размольный диск для размола с непрерывным мониторингом износа размольного элемента
US10960400B2 (en) * 2017-04-26 2021-03-30 Kolberg-Pioneer, Inc. Apparatus and method for an apron return assembly
WO2020198647A1 (en) * 2019-03-27 2020-10-01 Sgs North America Inc. Device for test milling an ore sample
US11293846B2 (en) 2019-03-27 2022-04-05 Sgs North America Inc. Device for test milling an ore sample

Also Published As

Publication number Publication date
FR2092338A5 (de) 1972-01-21
CA934350A (en) 1973-09-25
DE2018496A1 (de) 1971-10-28
AT327657B (de) 1976-02-10
GB1343810A (en) 1974-01-16
ATA45871A (de) 1975-04-15

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Legal Events

Date Code Title Description
AS Assignment

Owner name: SALZGITTER MASCHINENBAU GMBH, GERMANY

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:HAZEMAG DR. E. ANDREAS GMBH & CO., BY: KARL W. WISSING, RECEIVER IN BAKRUPTCY;REEL/FRAME:005216/0056

Effective date: 19890510

Owner name: WISSING, KARL-WILHELM, TRUSTEE IN BANKRUPTCY

Free format text: COURT APPOINTMENT;ASSIGNOR:HAZEMAG DR. E. ANDREAS GMBH & CO. KG, BY: THE DISTRICT COURT OF GERMANY BANKRUPT;REEL/FRAME:005216/0054

Effective date: 19881115

Owner name: HAZEMAG DR. E. ANDREAS GMBH & CO.

Free format text: CHANGE OF NAME;ASSIGNORS:HAZEMAG, HARTZERKLEINERUNGS-UND ZEMENT-MASCHINENBAU-GESELLSCHAFT MIT BESCHRANKTER HAFTUNG (CHANGED TO);HAZEMAG DR. E. ANDREAS KG (CHANGED TO);REEL/FRAME:005216/0044

Effective date: 19881208