With Plural Comminuting Zones Patents (Class 241/42)
  • Patent number: 10632503
    Abstract: A classifying device may be used to classify a granular material flow. The classifying device may comprise a first inlet that allows a first material flow into the classifying device, a second inlet that allows a second material flow into the classifying device, a static classifier, and a dynamic classifier. The static classifier may be positioned such that the static classifier at least partially surrounds the dynamic classifier. The classifying device may comprise a distributing device that is designed in such a manner that it supplies the material flow of the first inlet to the static classifier and the material flow of the second inlet to the dynamic classifier.
    Type: Grant
    Filed: October 12, 2015
    Date of Patent: April 28, 2020
    Assignees: THYSSENKRUPP INDUSTRIAL SOLUTIONS AG, THYSSENKRUPP AG
    Inventors: Michael Wilczek, Olaf Hagemeier
  • Patent number: 9609807
    Abstract: An agricultural harvesting machine includes a working assembly for processing a crop flow and a discharge accelerator for the processed crop that is designed as a unit to be installed in its entirety into an operating position (PB) downstream of the working assembly in the flow path of the crop stream. The discharge accelerator unit is readily deinstalled from the operating position (PB).
    Type: Grant
    Filed: September 10, 2013
    Date of Patent: April 4, 2017
    Assignee: CLAAS Selbstfahrende Erntemaschinen GmbH
    Inventors: Stefan Look, Lukas Grosse Wienker, Burkhard Weil
  • Publication number: 20150076258
    Abstract: A plant (1) and method for recovering plastic materials of post-consumption materials, such as vehicle bumpers and tanks, in the plant, downstream of the volumetric reduction grinder (2), there is provided an intermediate grinder (6) and the washing vat (9) and the centrifuge (12) additionally being arranged upstream of the windmill/granulator (14), while in the method, an intermediate grinding step is arranged upstream of the grinding/granulation step and a subsequent washing step and separation in the vat of the parts of foreign materials through the difference of specific weight, including ferrous, non-ferrous materials and alloys thereof, of the material made of intermediate size, before the grinding/granulation step through windmill/granulator, wherein the washing and centrifugation water is subjected to a continuous purification cycle.
    Type: Application
    Filed: September 18, 2014
    Publication date: March 19, 2015
    Applicant: C. & C. S.R.L.
    Inventor: Antonio FOLTIN
  • Publication number: 20140367501
    Abstract: A system for treating drill cuttings may include a first stage that receives the drill cuttings and generates a first drill cuttings slurry and a second stage that receives the first drill cuttings slurry and generates solids. The first stage may include a mixer receiving at least one additive from at least one treatment fluid supply. The mixer mixes the at least one additive with the drill cuttings to form a drill cuttings mixture and reduces the drill cuttings to a predetermined size. The first stage also includes a separator receiving the drill cutting mixture. The separator separates liquids from solids in the drill cuttings mixture to form the first drill cuttings slurry. The second stage may include a mixer that mixes a cleaning fluid from a second treatment fluid supply with the drill cuttings to form a second drill cuttings mixture. The second stage may also include a separator receiving the second drill cutting mixture.
    Type: Application
    Filed: June 12, 2014
    Publication date: December 18, 2014
    Applicant: BAKER HUGHES INCORPORATED
    Inventors: Anuradee Witthayapanyanon, Lirio Quintero, Paige M. Kiesewetter, Kenneth R. Carlsson
  • Publication number: 20140306044
    Abstract: The invention relates to a device (1) for sifting granular material into at least three fractions, comprising at least one static sifter (2) forming a first sifting stage and at least one dynamic sifter (3) forming a second sifting stage, wherein the static sifter (2) has several impact installations and conducting installations (8, 9) arranged one below the other in the manner of stairs in a sifter housing (4) having a first material inlet (5), a sifting gas inlet (6), and a coarse material outlet (7), wherein the dynamic sifter (3) is designed as a rod basket sifter having a rotary rod basket (12) and has a sifter housing (11) having at least one medium material outlet (17) and one fine material outlet (18).
    Type: Application
    Filed: November 23, 2012
    Publication date: October 16, 2014
    Inventors: Harald Guenter, Thomas Hanstien, Eberhard Neumann, Eggert De Weldige
  • Publication number: 20140209725
    Abstract: A system for processing a supply of post-consumer scrap linear low density or low density polyethylene film into near-virgin quality blown film product. The system includes tearing the supply of film in a shredder, wherein the surface area of the film is exposed, including delaminating the film. The torn supply of film is washed in a hot water bath including a surfactant. The film is agitated in the bath containing the surfactant wherein contaminants on the film are removed from the film. The washed film is ground into smaller pieces and additional washing of the ground film in a rotating friction washer occurs wherein additional contaminants are removed from the film. The ground film is then dried in a dryer and compacted in a compactor without addition of water into granulated objects of near-virgin quality blown film product.
    Type: Application
    Filed: April 4, 2014
    Publication date: July 31, 2014
    Applicant: Wisconsin Film & Bag, Inc.
    Inventors: Robert Francis Kulesa, James J. Feeney, Richard Wayne Carlstedt, Daniel William Blake, Buckell Gary Hacker
  • Publication number: 20140131491
    Abstract: A system and method for processing a supply of post-consumer scrap linear low density or low density polyethylene film into near-virgin quality blown film product. The method includes tearing the supply of film in a shredder, wherein the surface area of the film is exposed, including delaminating the film. The torn supply of film is washed in a water bath including a surfactant. The film is agitated in the bath containing the surfactant wherein contaminants on the film are removed from the film. The washed film is ground into smaller pieces and additional washing of the ground film in a rotating friction washer and a sink float tank occurs wherein additional contaminants are removed from the film. The ground film is then dried and compacted without addition of water into granulated objects of near-virgin quality blown film product.
    Type: Application
    Filed: January 23, 2014
    Publication date: May 15, 2014
    Applicant: Wisconsin Film & Bag, Inc.
    Inventors: Robert Francis Kulesa, James J. Feeney, Richard Wayne Carlstedt, Daniel William Blake, Buckell Gary Hacker, Abby Marie Johnson
  • Publication number: 20140014748
    Abstract: A method and system for processing biomass material from harvest to pelletizing includes a continuous shredding stage and grinding stage to reduce the size of the material. A fan pulls air through the shredder and the grinder to assist the movement of the biomass material through the shredder and the grinder. Due to the light weight of the biomass material, the material is transported between the shredding and grinding stages mechanically and pneumatically by a combination auger with air assist. The biomass material may include agricultural residues, such as corn stover. The process and equipment eliminates or minimizes damage to the carbohydrates in the biomass so as to maintain pre-grinding cellulose and hemi-cellulose levels.
    Type: Application
    Filed: September 17, 2013
    Publication date: January 16, 2014
    Inventor: James Russell Zeeck
  • Publication number: 20130119575
    Abstract: A process and apparatus for recycling plastic waste material, including shredding the waste material in a universal shredder apparatus and washing the waste material. The apparatus and method includes a dryer apparatus for drying substantially all moisture from the plastic, and an agglomeration process that is performed in an agglomeration apparatus which receives the dry film material from the dryer and creates a course mix of chopped material. Multiple in-line extruders process the cleaned plastic with filter screens positioned after each extruder to mix and filter the plastic into a final uniform mixed product harvested by a pelletizer.
    Type: Application
    Filed: September 20, 2012
    Publication date: May 16, 2013
    Applicant: NEXTLIFE ENTERPRISES, LLC
    Inventor: NEXTLIFE ENTERPRISES, LLC
  • Publication number: 20030038197
    Abstract: An apparatus for making hydrogen storage powder by hydride comminution which includes a hydride reactor with at least one chamber for tumbling powder.
    Type: Application
    Filed: October 7, 2002
    Publication date: February 27, 2003
    Inventors: Kwo Young, Michael A. Fetcenko, Stanford R. Ovshinsky
  • Patent number: 6000645
    Abstract: A concrete reclaimer having a pair of concentric mesh cylinders for separating wet concrete into its original components. The invention includes a hopper and feed screw for feeding wet concrete into the inner cylinder at a constant rate. The concrete is washed by a water spray as it passes through the cylinders. The inner cylinder is made from coarse mesh which allows sand and cement, but not gravel, to pass through. Gravel is deposited from the outlet end of the inner cylinder. The outer cylinder is made from fine mesh, allowing cement, but not sand, to pass through. Sand is deposited into the bottom of at least one dewatering screw, which allows water to drain as it elevates the sand. The dewatering screw is in thermal contact with a heated liquid tank to prevent the water from freezing. The cement is dropped through the outer cylinder into a series of settling ponds, where it is allowed to settle out of the water.
    Type: Grant
    Filed: January 27, 1999
    Date of Patent: December 14, 1999
    Assignee: BFK Technologies, Inc.
    Inventor: Mark A. Preisser
  • Patent number: 5794862
    Abstract: An apparatus and method for chemically and physically stabilizing contaminated soil is disclosed. The soil is homogenized in a homogenizer; dropped into a mixer below the homogenizer and mixed with an additive; then dropped to a processing terminus located below the mixer. The apparatus and method are useful for processing highly clumped and/or acidic soil, e.g., soil contaminated with mining waste.
    Type: Grant
    Filed: October 11, 1995
    Date of Patent: August 18, 1998
    Assignee: Itex Environmental Services, Inc.
    Inventor: Irfan A. Toor
  • Patent number: 5695133
    Abstract: There are a number of devices for washing/recycling thermoplastic. However, the devices tend to be designed on a scale for use at a central site. Additionally, the devices currently available do not have a positive feed travel mechanism. Rather the devices permit the thermoplastic to be "pushed" through at a rate dependent on the feed rate. The present invention provides a compact washer/recycler having a positive feed travel which is designed to shred, wash, dry and compact plastic at the location of its use.
    Type: Grant
    Filed: June 19, 1996
    Date of Patent: December 9, 1997
    Assignee: Nova Chemicals (International) S.A.
    Inventors: William A. Morse, Jr., Francis X. Cavanagh
  • Patent number: 5522555
    Abstract: A powder dispersion system, including a powder disperser and a control unit, supplies a controlled particle stream to a particle sizing system, instrument, or other processing device. The powder disperser includes a dynamic shear dispersion assembly and may include a fluidization assembly. An impact surface for deagglomeration of particles is located within a rapid acceleration chamber of the dynamic shear dispersion assembly. The particles are accelerated from the impact surface through an annular nozzle. A feedback loop dynamically controls the dynamic shear force applied to the aerosol transport gas, which in turn places reaction forces upon the particles, within the annular nozzle. The fluidization assembly includes a primary chamber for holding a powder sample and a secondary chamber for entraining particles of the powder sample in a transport gas stream. A pulsed gas jet directed into the primary chamber disperses particles of the powder sample into the secondary chamber.
    Type: Grant
    Filed: March 1, 1994
    Date of Patent: June 4, 1996
    Assignee: Amherst Process Instruments, Inc.
    Inventor: Trent A. Poole
  • Patent number: 5271570
    Abstract: A flour milling method and system therefor comprising the steps of separating foreign materials from raw wheat, humidifying the raw wheat, polishing the raw wheat, and conditioning the polished wheat, further comprises a step of cleaning the polished wheat at a subsequent step of the polishing the raw wheat. The flour milling method and system therefor may further comprises a step of stirring the cleaned polished wheat at a subsequent step of the cleaning step of the polished wheat. The bran powder which has been entered into the creases of the polished wheat at the polishing step, absorbs cleaning water and then flows out from the creases with the cleaning water. Since the bran powders in the creases of the polished wheat can be removed effectively, the milling efficiency is improved.
    Type: Grant
    Filed: August 10, 1992
    Date of Patent: December 21, 1993
    Assignee: Satake Corporation
    Inventors: Toshihiko Satake, Satoru Satake, Takeshi Ishii, Yoshihiro Tokui
  • Patent number: 5259560
    Abstract: Apparatus for cleaning chicken droppings from one or more mats used as nesting material in chicken nests in a chicken house. The invention includes a housing having a plurality of rollers therein for conveying a mat and pulverizing the chicken droppings adhering thereto. The rollers are paired with each pair including a fluted roller having a plurality of axially extending ridges thereon and a cylindrical roller defining a plurality of radial grooves thereon which cooperate with the ridges to pulverize the chicken droppings. Sprayers are provided to dislodge the pulverized chicken droppings from the mat. A plurality of guide plates are provided to guide the mat through the enclosure and support the mat during spraying.
    Type: Grant
    Filed: March 16, 1992
    Date of Patent: November 9, 1993
    Inventor: Bill W. Dyer
  • Patent number: 5257831
    Abstract: The rag tearing machine embodies an inlet station 1 in which the materials to be processed for a first time 23 and recycled waste 19 are poured, separately, onto the circulating belt 2. Several rag tearing stations (4a, 4b) are each followed by fan groups (5a, 5b), including side doors 8 access for which throw a material coming from the preceding station to a filtering box 9 in which powder, after a sharp bend 10 separates from the material by passing through a pierced plate 11; the material then falls down and passes to the following station and so on until the end of the machine. The machine further includes gates 14 for bypassing subsequent stations and if the material is considered sufficiently processed, the respective gate is opened and the material goes out of the machine through a duct 15.
    Type: Grant
    Filed: February 26, 1992
    Date of Patent: November 2, 1993
    Inventor: Francisco M. Garcia
  • Patent number: 5215017
    Abstract: A fuel feed system and method for feeding low grade fuels to a fluidized bed furnace including an enclosure with a fuel inlet for introducing the fuel into the enclosure, an inlet for introducing air into the enclosure so as to propel the fuel through the enclosure, and baffles disposed in the path of the fuel in a manner to reduce the size of the fuel particles prior to the introduction of the fuel into the furnace.
    Type: Grant
    Filed: January 27, 1992
    Date of Patent: June 1, 1993
    Assignee: Foster Wheeler Energy Corporation
    Inventor: John T. Tang
  • Patent number: 5016824
    Abstract: Method and an apparatus for controlling the production of thermomechanical pulp meter chips by metering elements (9, 10) into a feed chest (2), and by feed elements (3, 7) connected to the feed chest feeds chips for refinement between thermomechanical pulp refining discs (5). Water is added to the chips prior to feeding the chips between the discs (5). Moisture content of the thermomechanical pulp is measured after the thermomechanical pulp refiner at least in a semicontinuous fashion by at least one measurement device (21, 22, 23, 24) operating on-line, and on the basis of measured moisture content, the quantity of chips and water to be metered is controlled so as to regulate the moisture content to a desired level of having a constant value by, e.g., increasing the volume of metered chips and simultaneously decreasing the quantity of fed water for an increasing trend of moisture content, and correspondingly, applying an opposite strategy to counter a decreasing trend of moisture content.
    Type: Grant
    Filed: January 10, 1990
    Date of Patent: May 21, 1991
    Inventors: Pertti Pietinen, Aslak Savonjousi
  • Patent number: 4986479
    Abstract: A fluid jet shredder apparatus includes a conveyor for conveying a stream of material to be shredded. The conveyor has openings formed therein. A shredding station in position adjacent the conveyor and includes a fluid jet cutting nozzle directing a high pressure jet of fluid onto the stream of material. As a result, portions of the material are separated from the stream of material. The separated portions of material pass through the openings in the conveyor. A subsequent shredding station can be positioned downstream of the initial shredding station for directing a second and higher pressure jet of fluid onto the stream of material. The subsequent shredding station can therefore shred material which the initial, relatively lower pressure fluid jet failed to shred from the stream. Sequential shredding stations of incrementally increased pressure can progressively shred material of increased hardness from the stream. The fluid jets can selectively include an abrasive material.
    Type: Grant
    Filed: August 14, 1989
    Date of Patent: January 22, 1991
    Assignee: Ingersoll-Rand Company
    Inventors: Michael C. Swarden, Henry B. Faulkner, Walter L. Brassert, James E. Stoudt
  • Patent number: 4884756
    Abstract: A system for the treatment of infectious waste including apparatus for receiving, shredding, disinfecting, and separating waste material. A manually operated entry device provides input for quantities of solid waste into a feeding channel wherein a feeding ram moves the waste onto a series of shredding disintegrators which achieve material size reduction. Following shredding, the waste is gravitationally transferred into disinfecting fluid contained within an enclosed decontamination and separation device. Solid waste is continuously separated from the disinfecting fluid. The decontaminated solid waste is then deposited into a storage device.
    Type: Grant
    Filed: February 1, 1989
    Date of Patent: December 5, 1989
    Inventor: Erich H. Pearson
  • Patent number: 4832268
    Abstract: A mill for grinding powder material is disclosed having a cylindrical separation chamber into which the powder material is fed as a dispersion in a gas stream. Powdered material initially is supplied through two spaced powder inlets each located between a jet and a venturi throat assembly so that milling fluid introduces the powder material through the venturis and the venturis are mounted in opposition so that the gas streams carrying the powder impinge on one another to impart grinding. The impinged material passes to a third venturi to be entrained in a gas fed from a third jet nozzle and introduced through the venturi into the separation chamber. The mill is of particular use for milling pigmentary powders.
    Type: Grant
    Filed: August 5, 1988
    Date of Patent: May 23, 1989
    Assignee: Tioxide Group PLC
    Inventors: Andrew J. Haddow, Trevor Carter
  • Patent number: 4753660
    Abstract: The invention relates to an apparatus and method for producing a free flowing coal suspension high in solids content. The coal is ground in at least two stages utilizing a mill having a calibrating effect in one stage and a mill without calibrating effect in another stage and adding a sub-quantity of viscosity reducing additive to the coal before each grinding. A drying of the coal or reconcentration of the suspension is not required. A roller mill operating on the principle of materials bed comminution is preferred as the non-calibrating mill in the first grinding stage and a rotating drum mill or a vibration grinding mill with rods as grinding bodies is preferred as the calibrating mill.
    Type: Grant
    Filed: March 17, 1986
    Date of Patent: June 28, 1988
    Assignee: Klockner-Humboldt-Deutz Aktiengesellschaft
    Inventors: Hans Kellerwessel, Hans-H. Gildemeister, Jurek Golda, Peter Zahr, Gerhard Keichel
  • Patent number: 4471916
    Abstract: An apparatus and method for treating for disposal organic waste material carried within a sludge, by adding to the sludge an alkali metal silicate and a setting agent, is disclosed. The apparatus includes several mixers, each having a trough with an input end and a discharge end, at least one rotatable shaft mounted longitudinally along the trough, a plurality of blades mounted to the shaft, and a drive for rotating the shaft. The sludge is deposited within a first mixer, and then directed from the mixer into a tank. A series of chopper pumps recirculate the sludge into the tank, and alternatively, the sludge may be passed through an additional mixer. Leaving the tank, the sludge is directed into a second mixer at its input end. Water is introduced at the input end, and a setting agent is added along the trough at a point adjacent the input end. Further along the trough, an alkali metal silicate is introduced. The mixture is recovered from the second mixer, and carried to a remote location for setting.
    Type: Grant
    Filed: August 30, 1982
    Date of Patent: September 18, 1984
    Assignee: Chemfix Technologies, Inc.
    Inventor: David L. Donaldson
  • Patent number: 4456503
    Abstract: A method and a device for the manufacture of mechanical pulp from lignocellulosic material by forcing the said material into contact with a grinding disc (1) which revolves about a central axle (2) perpendicular to the two end faces of the disc. The material is supplied in bulk, particulate form, preferably as wood chips, a large number of particles simultaneously being retained, compressed and, in the presence of water, forced into contact with one or more grinding areas (5) on one or both end faces of the grinding disc. The disc is enclosed in a sealed, pressurized housing (6).
    Type: Grant
    Filed: September 29, 1982
    Date of Patent: June 26, 1984
    Assignee: Sunds Defibrator AB
    Inventor: Hjalmar S. I. Bystedt
  • Patent number: 4454992
    Abstract: Particulate cellulose insulation material is rendered fire retardant by a wet process requiring considerably less fire retardant composition than normally employed in the usual dry processes or in wet processes proposed heretofore, and yielding a product with significantly enhanced insulating properties. Impregnation of a cellulosic insulating material, such as waste paper in finely divided form, with an aqueous solution of a non-hygroscopic fire retardant composition, such as boric acid, a borate, or the composition of U.S. Pat. No. 3,983,040, is carried out under conditions whereby a minimum amount of water is first utilized for the purpose of dissolving the fire retardant composition and to serve as a carrier in distributing it throughout the cellulosic insulating material. For example, only from about 14 to 45% by weight of add-on water is utilized in the presence of from about 5 to 10% by weight of the fire retardant composition and preferably in the presence of a surfactant.
    Type: Grant
    Filed: February 25, 1983
    Date of Patent: June 19, 1984
    Inventor: Samuel M. Draganov
  • Patent number: 4445973
    Abstract: A method and a device for the manufacture of mechanical pulp from lignocellulosic material by forcing the said material into contact with a grindstone (1) which revolves about an axle (2). The material is supplied in bulk, particulate form, preferably as wood chip, a large number of particles simultaneously being retained, compressed and, in the presence of water, forced into contact with one or more grinding areas on the circumferential surface of the grindstone (1). The grindstone(1) is enclosed in a sealed, pressurized housing (5).
    Type: Grant
    Filed: September 29, 1982
    Date of Patent: May 1, 1984
    Assignee: Sunds Defibrator AB
    Inventor: Hjalmar S. I. Bystedt
  • Patent number: 4177952
    Abstract: An impact scrubber for removing coating materials from the surfaces of particulate matter such as foundry sand and the like comprises a lift tube open adjacent upper and lower ends for containing a high velocity fluidized stream of said particulate matter. A fluid injector is mounted adjacent the lower end of the lift tube for moving the particulate matter into the lift tube to form an upwardly flowing, high velocity turbulent fluidized stream. An adjustable inlet valve is provided adjacent the fluid injector for regulating the flow of sand into the high velocity stream of fluid moving into the lift tube. A target is spaced above the open upper end of the lift tube providing an impact area for receiving the flow of high velocity fluidized particulate matter which impacts against the target. The coating material is loosened from the sand grains by the impact at the target and during the turbulent flow.
    Type: Grant
    Filed: April 24, 1978
    Date of Patent: December 11, 1979
    Assignee: National Engineering Company
    Inventor: Leslie D. Rikker
  • Patent number: 4175708
    Abstract: Disclosed is a method of transporting liquid pitch containing lumpy coke wherein the lumpy coke contained in the liquid pitch is pulverized by a specific procedure and the pitch containing the thus pulverized coke is then transported. Disclosure is also made for a specific apparatus used for the method.
    Type: Grant
    Filed: January 19, 1978
    Date of Patent: November 27, 1979
    Assignee: Kureha Kagaku Kogyo Kabushiki Kaisha
    Inventors: Naoshi Kawabe, Hisatsugu Kaji, Naotaka Miwa, Hajime Nakanishi, Fumiaki Tanaka, Tatsuya Inoue
  • Patent number: 4088528
    Abstract: In the continuous production of paper pulp from ligno-cellulose raw material, the raw material is subjected to grinding and/or delignification by passing it in the form of small pieces between interpenetrating helicoidal surfaces driven synchronously in rotation inside a casing. The pitch of the helicoidal surfaces is arranged to provide at least one supply zone in which the material is driven downstream by rotation of the surfaces and at least one braking zone in which the material is braked.
    Type: Grant
    Filed: July 27, 1976
    Date of Patent: May 9, 1978
    Inventors: Pierre Berger, Christian DE Choudens, Gerard Lombardo, Pierre Monzie
  • Patent number: 4032446
    Abstract: An improved waste material handling system includes a plurality of waste food disposer units which are operable to disintegrate waste food materials to form a slurry. The system also includes a pulper unit which is operable to disintegrate solid waste materials, such as paper, cardboard boxes, plastic bags, etc., to form a slurry. The waste material slurry is conducted from the waste food disposer units and pulper unit to a press which extracts water from the slurry. To prevent the discharge of waste material slurry from an active one of the waste food disposer units to an inactive one of the waste food disposer units and/or the pulper unit, check valves are associated with each of the waste food disposer units and the pulper unit. A pump is also associated with each of the waste food disposer units and the pulper unit to promote a flow of slurry from the units to the press.
    Type: Grant
    Filed: May 5, 1976
    Date of Patent: June 28, 1977
    Assignee: Hobart Corporation
    Inventor: Blaine Monroe Miller, Jr.
  • Patent number: 3948448
    Abstract: An improved comminuting rolling mill wherein a solid material such as mineralic loose or bulk materials are introduced into a gap between opposed parallel counter rotating comminuting rollers with the material being supplied by a delivery device above the rollers having a discharge slot extending the length of the gap between the rollers and being provided with means for accelerating the charging material to the speed of roller surface travel, with the delivery device having opposed porous walls and having means for supplying a flow of air through said walls for fluidizing the material so that fluidized material flows into the gap between rollers and the device being provided for pressurizing the delivery device so that the material is carried between the rollers at the desired speed.
    Type: Grant
    Filed: August 1, 1974
    Date of Patent: April 6, 1976
    Assignee: Klockner-Humboldt-Deutz Aktiengesellschaft
    Inventors: Peter Wehren, Heinz Meder