Abstract: A harvester includes a chopper assembly configured to process harvested crops and an elevator positioned downstream of the chopper assembly such that the harvested crops processed by the chopper assembly are received by the elevator. The harvester also includes a storage hopper located adjacent to a distal end of the elevator and positioned to receive the harvested crops therefrom, and a conveyor extending within the storage hopper between a first end and a second end of the conveyer, with the conveyor configured to carry the harvested crops between its first and second ends towards a discharge opening of the storage hopper. Additionally, the harvester includes a door positioned adjacent to the discharge opening of the storage hopper, and a door actuator coupled to the door. The door actuator is configured to move the door relative to the discharge opening between an opened position and a closed position.

Abstract: A destruction device capable of destroying a plurality of types of storage devices includes: a support plate mounting part to which a support plate is detachably mounted; a crushing member mounting part to which a crushing member is detachably mounted; a support plate detection part capable of detecting the support plate mounted on the support plate mounting part; a crushing member detection part capable of detecting the crushing member mounted on the crushing member mounting part; and a control unit that determines whether the support plate detected by the support plate detection part and the crushing member detected by the crushing member detection part correspond to a same type of storage device, and executes a crushing process for crushing the storage device upon determining that the support plate and the crushing member correspond to the same type of storage device.

Abstract: A cone crusher includes a crushing chamber formed between inner and outer crushing shells, a drive shaft that gyrates the crushing head to crush material in the crushing chamber, and a feeding hopper for feeding material to the crushing chamber. A measurement device measures an amount of material present in the feeding hopper. A control system controls, based on the measured amount of material present in the feeding hopper, at least one crusher operating parameter which is chosen from i) an rpm of the drive shaft, and ii) a width of a discharge opening formed between the inner crushing shell and the outer crushing shell.

Abstract: A bale processor with a bale processing bin that has a bale cutter therein and an engagement section on the bale cutter for supporting part of a bale. A conveyor section supports another part of the bale. The bale processor has a load sensor that senses the load, or something that is a function of the load, on the bale cutter and a controller controls feeding of the bale to the bale cutter and/or the position of the engagement section, based on the function of the load on the cutter.

Abstract: A gyratory or cone crusher includes a measuring apparatus suitable for measuring load of the crusher, a first element placed on a main shaft of the crusher and a first detector suitable for detecting the first element which first detector provides a trigger starting a measurement revolution, and at least one second element placed on a drive shaft of the crusher and a second detector suitable for detecting the second element and providing a trigger corresponding to a certain rotational position of an inner blade of the crusher. The system includes an output to a screen for presenting the loads or averages of the loads corresponding to rotational positions of the inner blade of the crusher. Detections of the monitoring system can be used for controlling and monitoring a crushing event, such as by changing an area or a location of a feed opening of the crusher.

Abstract: A crusher is provided having improved wear resistance and crushing capacity. Particularly, the crusher provides an improved mechanism for adjusting the closed side setting by acting on an adjustable jaw, rather than the moveable jaw. The crusher includes a moveable jaw, an adjustable jaw, and a frame that supports the adjustable jaw and the moveable jaw such that the adjustable jaw and the moveable jaw define a crushing chamber having an upper opening for receiving a material to be crushed and a lower opening for expelling crushed material from the chamber after crushing. The crusher also includes a drive mechanism coupled to the moveable jaw for directing reciprocating motion of the moveable jaw and an adjustment mechanism coupled to the adjustable jaw for altering an angle of the adjustable jaw and, thereby, altering a closed side setting of the crushing chamber.

Abstract: Paper shredder thickness calibration using a Hall effect torque detector coupled to a paper shredder motor, producing a signal corresponding to the paper shredder motor rotation, a controller receives the signal and determines a paper shredder motor torque from the signal corresponding to the rotation of the paper shredder motor, with the torque corresponding to shreddant thickness. Signal is compared to predetermined maximum signal beyond which overload is signaled. Also, a method of operating a paper shredder having a rotating motor to comminute shreddant, including providing a Hall effect rotor and sensor; creating a torque signal based on a full load motor torque, and comparing the current torque signal to the full load torque signal.

Abstract: A device for comminuting media materials that store sensitive information. The device is a rotating mill core with removable flat edged blades, a set of stacked bed knives and a screen. The mill core rotates in close proximity to the bed knives to shear the material being fed, and in close proximity to the screen in order to grate the material. A flywheel is attached to the mill core in order to conserve rotational energy and improve the efficiency of the device. A knurled roller is installed in the device that feeds the material into the knife mill as well as holds the material steady during the initial shear. Vacuum ports facilitate cleanup.

Abstract: This invention relates to a paper shredder. A first stage shredder accepts paper from a hopper. The first stage shredder includes two knife shaft assemblies with a plurality of sequentially oriented knives and spacers on hexagonal shafts. A second stage shredder accepts the output of the first stage shredder. The second stage shredder has two counter rotating shafts with saw tooth disk knives and separating spacers and cuts the paper finer than that of the first stage shredder. A third stage shredder may be connected to the second stage shredder providing even further paper size reduction.

Abstract: A thermally controlled coffee grinder and method are disclosed. In some embodiments, a thermally controlled coffee grinder may have a heating or cooling element to adjust the temperature of a component of the coffee grinder in response to a measured thermal state of a component in the grinder in order to improve dosing consistency, ground coffee quality, etc. In other embodiments, a thermally controlled coffee grinder may detect a thermal state in the coffee grinder and utilize a computer control to adjust for consistent dosing amounts.

Abstract: The invention relates to a roller mill having a grinding table, at least one grinding roller and at least two drives with a rotor winding for driving the roller mill and at least one adjustment device for adjusting the motor torque of at least one drive, the adjustment device being connected to the rotor winding of at least one drive in order to influence the rotor current.

Abstract: A method has been developed that estimates from the on line measurements of readily available process variables the proportion of the mass of fiber in the refining zone of a chip refiner relative to the mass with a full refining zone. This estimate of the filling factor is used to determine the margin available to load the refiner and the control action needed to avoid abnormal operation.

Abstract: There is described a crushing plant and a method for controlling the same. The crushing plant includes a crusher (1) and a feeding arrangement (3), and is driven by a diesel engine (13). A load value related to the diesel engine is retrieved e.g. by means of a J1939 interface. If the retrieved value exceeds a predetermined threshold value, the control loop of the feeding arrangement (3) is altered. Thereby it can be avoided that the diesel engine (13) stalls, such that continuous operation of the crushing plant may be ensured.

Abstract: Described and claimed is a method, in which the state of a mill, which consists of a stator and a rotor and is driven by an alternating current motor, is derived from the rotational speed of the mill work. The rotational speed is measured with the aid of a rotating component connected to the mill work in a torque-proof way, especially with a Hall sensor, which co-operates with a permanent magnet fastened to said component. The determined speeds—normal for a normal operation of the mill and zero or very low in the event a blockage of the mill work—are put in relation to the idling rotational speed, which is also determined and is put in relation to the mains frequency. The determined rotational speeds are stored, and can be displayed. When there is a blockage, an alarm can be sounded.

Abstract: In a dual-gradient drilling apparatus, a subsea solids processing unit includes a housing, a solids processing mechanism disposed in the housing between a drilling mud inlet and a drilling mud outlet, and a flushing mechanism configured to flush the solids processing mechanism with a flushing fluid. A subsea solids processing unit may be controlled by rotating the solids processing mechanism in a forward direction and increasing a drive torque when a measured speed of the solids processing mechanism is below a desired rotation speed. The desired rotation speed may be decreased when a measured torque exceeds a selected maximum and a rotation direction of the solids processing mechanism may be reversed when the measured speed falls below a selected minimum.

Abstract: A grinding apparatus for dispensing a dose of ground frozen material starting from a frozen block includes a grinding unit for grinding the frozen block in order to provide an amount of ground frozen material and a feeding unit for feeding the frozen block to the grinding unit. In particular, the feeding unit includes a feeding member that is adapted for moving frozen block for a desired predetermined grinding stroke against grinding unit such that a grinding length of block is ground. A grinding unit provides at least one grater and one motor for causing the grater to rotate. In order to obtain a desired weight of the dose, a volume of frozen material is calculated that corresponds to said weight, since the density of the frozen material is known.

Abstract: The method is used to determine the filling level of a loaded mill container (2). The container (2) has a drive torque (M) applied to it by means of a drive (6), and causes it to rotate. The drive torque (M) on the drive (6) is set by means of a predeterminable drive test sequence. A time/rotation speed profile of a rotation speed of the container (2) which results from the drive test sequence is recorded, and is analyzed. The filling level is determined on the basis of the results of the analysis. The method produces up to date, accurate information, determined during the milling operation, about the filling level of the container (2).

Abstract: The present invention relates to a control system for a rotary grinder. Rotary grinders control systems of the present invention are, for example, used to grind plastic or wood to reduce the size of the material to a desired size. Material to be ground is forced by an hydraulic ram toward a rotor having a plurality of cutters thereon. The control system is capable of controlling the grinding operation as a function of ram velocity and pressure as well as power consumption by the rotor.

Abstract: A method, and method-implementing system structure, for metering the flow of material through the shredding zone in a rotary shear shredder, which zone is defined, at least in part, by confrontingly rotating knives that are carried on a pair of adjacent, power-driven, nominally matched-motion counter-rotating shafts. The method includes holding the speed and rotational direction of one of the shafts essentially constant while selectively varying, in a manner variably differentiating the relative rotational motions of the two shafts, the speed, and under certain circumstances also the direction, of rotation solely of the other shaft.

Abstract: A connection arrangement between a feed roller and a gearbox of a field chopper has a first shaft (25) with a central bore (26) that is rotatingly supported around an axis of rotation D, in a gearbox housing (30). A second shaft (32) is connected to a feed roller. The second shaft (32) is rotatingly supported around the axis of rotation D. The second shaft (32) has a central bore (33) that is aligned with the central bore (26) of the first shaft (25). A connecting journal (37) rests in the central bore (26) of one of the two shafts (25). The connecting journal (37) is form-fittingly connected to the central bore for torque transmission. It is axially displaceable along the axis of rotation D between a connected position where it is inserted into the central bore (33) of the other of the two shafts (32), and a released position, where it is pulled out of the central bore (33) of the other of the two shafts (32).

Abstract: A food waste disposer has a motor driven with pulse width modulation (“PWM”). A grinding profile is controlled based on PWM values of the PWM controller driving the motor. In an aspect, controlling the grinding profile includes varying the speed of the motor based on the PWM values. In an aspect, the grinding profile is initiated after the food waste disposer is started and a PWM value exceeds a set value indicating the presence of a grinding load in a grinding section of the food waste disposer. In an aspect, it is determined that the grinding load has been sufficiently ground once the PWM value does not exceed a first set value after the grinding profile has been initiated. In an aspect, corrective action is initiated when the PWM value exceeds the set value after a predetermined period of time.

Abstract: A inventive feeding mechanism continuously feeds and continuously subjects to shredding, cutting, recycling, sorting, or other processing, a load consisting of a mixture of different-thickness materials, such as a mixture of paper, compact disks (CDs), cassette tapes, videotapes, etc. The auto-adjusting feeding mechanism is useable in high-security destruction, food processing, recycling, sorting, processing, and other applications.

Abstract: An integrated beverage dispensing and cleaning system comprising: at least one blender module which blends and/or mixes ice, at least one other ingredient, and/or at least one mixin within a beverage container, thereby producing the beverage; and a cleaning assembly integrated with the blender module, wherein, upon removal of the beverage container from the blender module, a cleaning mode is initiated.

Abstract: There is described a crushing plant and a method for controlling the same. The crushing plant includes a crusher (1) and a feeding arrangement (3), and is driven by a diesel engine (13). A load value related to the diesel engine is retrieved e.g. by means of a J1939 interface. If the retrieved value exceeds a predetermined threshold value, the control loop of the feeding arrangement (3) is altered. Thereby it can be avoided that the diesel engine (13) stalls, such that continuous operation of the crushing plant may be ensured.

Abstract: A inventive feeding mechanism continuously feeds and continuously subjects to shredding, cutting, recycling, sorting, or other processing, a load consisting of a mixture of different-thickness materials, such as a mixture of paper, compact disks (CDs), cassette tapes, videotapes, etc. The auto-adjusting feeding mechanism is useable in high-security destruction, food processing, recycling, sorting, processing, and other applications.

Abstract: A beverage and ice dispenser that dispenses both beverages and cubed or crushed ice. Beverages are dispensed from dispensing heads. Cubed ice is stored in a bin. A duct leads from the bin. The duct has first and second outlet openings. A chute leads from the outlet openings. The chute has a single discharge opening from which ice from both duct outlet openings is discharged. An ice crusher is between a first outlet opening and the chute. A gate opens and blocks the flow path from the second opening into the chute. When cubed ice is desired, the gate is spaced from the second opening so that cubed ice is discharged from the duct and chute. When crushed ice is desired, the gate closes the second opening. Ice flows out of the first opening, is crushed by the ice crusher and discharged through the chute.

Abstract: A coffee maker includes a valve mechanism having a micro switch, an electromagnetic valve, a magnetic covering board activated by the electromagnetic valve for opening or closing a powder path, and a spring interconnecting the covering board and the electromagnetic valve. A motor-driven grinding mechanism includes two ring-shaped outer grinding members having teeth facing each other, and a spring biased inner grinding member including a hollow feed rod with a lead screw formed thereon. A powder fineness adjusting mechanism includes an adjustment lever. In a powder fineness adjustment for producing coarse coffee powder, pivoting the lever toward one direction will pivot an abutment member and move the same outward to push one grinding member for increasing a space between the grinding members filled with coffee beans to be ground. Pivoting the lever toward the other direction will produce fine coffee powder.

Abstract: In a crushing system, an interlocked operation of operation units including a grizzly feeder, a crusher and a delivery conveyor and so on is stopped by depressing an interlock OFF switch (94). For this, after stopping the grizzly feeder, a stop command section (122B) outputs a stop command to the crusher and the delivery conveyor only when a load detector (110) once detects the load on the delivery conveyor and a determining section (122A) determines that the load is cleared out and there is no remaining crushed material. Thus, if compared with conventional crushing systems adapted to stop the operation units only after the elapse of a predetermined time period, the crushing system can reliably prevent the crushed material from remaining on the delivery conveyor so that it is no longer necessary to worry about a situation where the crushed material remaining on the delivery conveyor has to be removed.

Abstract: A horizontal grinder is disclosed herein. The grinder includes a grinding structure and upper and lower feed conveyors for feeding material toward the grinding structure. The upper feed conveyor is positioned above the lower feed conveyor such that the material fed toward the grinding structure travels between the upper and lower feed conveyors. The grinder also includes a power source for rotating the grinding structure. A controller is provided for controlling the speed of at least one of the lower and upper feed conveyors in proportion to an operating characteristic of the power source.

Abstract: In an assembly including a diesel engine, a fluid coupling connected to the flywheel of the diesel engine, a comminuting machine and a conveyor for feeding the comminuting machine, a fluid coupling module is common to various output power train assemblies. Slip speed of the fluid coupling between impeller input and runner output shafts is measured, and modulates or regulates the process feed rate of the conveyer. An electrically actuated control valve acts as an oil flow diverter valve directing oil into the fluid coupling impeller when a signal to engage the coupling is given, and in response to a signal from an over-temperature sensor when the temperature of circuit oil leaving the element exceeds a preset set point value, diverts the oil to a reservoir, thereby permitting the impeller and runner cavity to evacuate, which separates the engine from the load.

Abstract: A grinder for comminuting waste material comprises a frame structure (18, 20). A grinding rotor (24) is rotatably carried by the frame structure (18, 20.) The grinding rotor (24) carries a plurality of cutting tools (36) cooperating with a counter blade (26, 28) carried by the frame structure (18, 20). Two plate chain conveyors (68, 70) are vertically aligned so that working runs (80, 120) thereof form a converging moving wall funnel positively feeding pieces (146, 148) of material to be comminuted towards a grinding unit (12) formed by the grinding rotor (24) and the counter blade (26, 28).

Abstract: Method and apparatus for recycling plastic materials includes the movement of hoppers along cutting edges.

Abstract: A device for controlling load on a first motor whose load is affected by a second motor, comprises a controller having a first input for being connected to a horsepower transducer connected to the first motor being monitored and an output for being connected to the second motor; and a program configured to receive the first input and generate the output responsive to the input.

Abstract: A system of processing big refuses such as spring-containing mattresses according to the present invention includes a crushing process for crushing big refuses such as spring-containing mattresses by a single axial crusher capable of crushing them into a certain particle size or less, a magnetic-force grading process for grading iron material by a magnetic-force grader from crushed pieces crushed in said crushing process, and a wind-force grading process for removing light-weight refuses such as fiber adhering to iron material graded in said magnetic-force grading process by a wind-force grader.

Abstract: The harvesting machine includes an attachment, a feed device for material to be harvested, a cutting drum for the material to be harvested, an ejection means for conveying the material from the cutting drum, an advantageously hydrostatic drive for the feed device, a drive for the cutting drum, respective rotation speed sensors for measuring actual rotation speeds of the cutting drum and the feed device and an electronic analysis unit.

Abstract: The present invention is a mobile crusher and a method for controlling the same, wherein the most suitable amount of crushed substances can be always secured so as to obtain crushed substances having a desired particle size distribution.

Abstract: In a self-propelled crushing machine having a vehicle body, a traveling body mounted on the lower portion of the vehicle body, a crusher mounted on the upper portion of the vehicle body, and a hopper mounted on the upper portions of the vehicle body having a feeder for supplying an object of crush to an inlet of the crusher, the self-traveling crushing machine includes crusher driving means for driving the crusher, an excessive load detector for detecting whether an excessive load is acting on the crusher driving means or not, a feeder driver for driving the feeder, and control means for stopping the feeder driver when excessive load is detected by the excessive load detector means and actuating the feeder driver when excessive load is not detected.

Abstract: A boiler fuel distribution control system in which a boiler fuel demand signal is employed to regulate the rate of grinding of the fuel within predetermined limits of air supply so the grinding of the fuel material is accomplished at a desired mill grinding speed and within a fluid bed differential pressure across the grinding mill to maintain a supply of fuel adequate to keep up the desired boiler operation. It is also a system in which stand alone isolated control computer accessories can be temporarily manually adjusted to the control system until a replacement is available.

Abstract: The comminuting machine includes a housing provided with a rotary impact mechanism. Infeed apparatus including a conveyor and a revolving intake roll act upon the infed material for conveying the same to the rotary impact mechanism. An entrance gap is defined between an impact ledge and the rotary impact mechanism and provides initial comminution. The impact ledge is mounted at a carrier which also supports a pressure fluid operated motor for driving the infeed apparatus. The entrance gap is followed by an impact plate which cooperates with the rotary impact mechanism in further disintegrating the infed material.

Abstract: An improved arrangement for feeding material through a material reducing machine. An inclined wall is positioned strategic to a material reduction unit and a plunger of the machine. A lower beveled edge of the inclined wall is positioned in close proximity to the material reduction unit and above the plunger. The plunger forces material toward the material reduction unit and the inclined wall. Material that is below the lower edge of the wall will be forced into the material reduction unit and material that is above the lower edge will be forced to elevate on the inclined wall thus preventing jamming of the forced feed mechanism of the machine. Controls are provided to control the rate of movement of the plunger in correspondence with the rotational rate of the material reduction unit. The rate at which the plunger moves toward the material reduction unit is decreased when the rotational rate of the material reduction unit decreases.

Abstract: Apparatus for handling lug scrap strips produced by the slitting of metallic strips in a metallic strip slitter. The lug scrap strip handling apparatus includes air ducts for transfer of the lug scrap strips, a scrap cutter provided in the air duct for continuously cutting the long lug scrap strip to a predetermined length, a blower provided downstream of the scrap cutter and connected to the air duct, a scrap collector provided at the end of the air duct, and a scrap press attached to the scrap collector. The scrap cutter drive is controlled in synchronization with the line speed of the metallic strip slitter to prevent plugging of the scrap cutter by the lug scrap strip pieces.

Abstract: A waste disposer having a rotatable shredding element for grinding waste in a flushing liquid, an outlet for discharging ground waste material in liquid to a drain, an electrically-powered motor for driving the rotatable shredding element and a source for supplying flushing liquid the disposer that includes a detector for sensing the amount of electrical current flowing to the motor. The system includes, at least, one valve for controlling the flow of flushing liquid to the disposer which valve is controlled by means of a controller that is responsive to the electrical current detector. The controller increases the amount of flushing liquid falling into the disposer in response to a detected increase in the amount of electrical current flowing into the motor. The invention optionally includes a second valve for controlling flushing liquid to the disposer at a lower rate, which second valve is opened whenever the electrical is activated.

Abstract: A control system for a refuse shredder composed of a refuse feeding section and a refuse shredding section detects a stagnating state of refuse to adjust the feed rate, detects idling of the feeding section and restores it to a proper state, detects a tendency of tripping of a shredder drive motor and prevents such tripping, and generally automates an operation of the shredder. The system includes an image pickup device for picking up an image of a refuse inlet of the shredder, an image processor for binary-coding an image signal generated by the image pickup device to obtain a characteristic quantity of the refuse, and control calculator for calculating and outputting a control signal for controlling the feeding section and the shredding section on the basis of the characteristic quantity of the refuse obtained by the image processor.

Abstract: An economical apparatus and method for reprocessing scrap film. The apparatus includes a film-air separation chamber for separating air from incoming strips of scrap film, a cutter for cutting the strips into fine pieces, and a storage tank or further reprocessing means to which the cut pieces of scrap film are conveyed. A air bypass line having a computer-controlled valve conveys air directly from the film-air separation chamber to the cutter outlet when the valve is in an open position, and causes all of the air to flow into the cutter inlet when the valve is in a closed position. The open or closed position of the air bypass valve depends upon the cutter motor power, which varies as the volume of scrap film in the cutter varies. Due to the inclusion of the accurately controlled air bypass valve, only a single fan is needed to convey the film into and out of both the film-air separation chamber and the cutter.

Abstract: A grain cleaning machine comprising a cleaning chamber including a cleaning roll for cleaning uncleaned grain white, a screw conveyor for feeding the uncleaned grain into the cleaning chamber, a discharge adjusting device disposed in a grain outflow region of the cleaning chamber, and a torque sensor for detecting an internal load of the cleaning chamber. The discharge adjusting device is spring-loaded in a direction to stop outflow of white grain from the cleaning chamber, and is movable against the spring load in a direction to enhance outflow of the white grain. The discharge adjusting device is controllable on the basis of torque detection by the torque sensor to maintain the internal load of the cleaning chamber in a predetermined value.

Abstract: A method and apparatus for producing uniform pulp yields, wherein at least a refiner is controlled in accordance with the UV absorbance of the lignin dissolved in the digester cooking liquor, thereby to produce for a given quantity of wood chips a uniform pulp yield. A backflow control valve is automatically adjusted to maintain uniform flow of a sample of the digester cooking liquor through a UV analyzer, and a flushing arrangement is provided for flushing out contaminates such as sulphur dioxide from the system. Preferably the refiner is of the two-stage type, the first stage being automatically adjusted as a function of the UV absorbance of the digester cooking liquor, and the second stage being automatically adjusted as a function of the freeness of the output fiber slurry. Also, one or more of the cooking parameters is controlled by the UV analyzer to control the fiber yield.

Abstract: A wood cutting knife is provided for producing wood chips or flakes. The knife includes a central cutting member, and two wing members positioned on opposite sides of the central cutting member. The height of the wing members determines the depth of cut of the cutting knife, including the central cutting member. Also provided is a wood processing machine for supporting such cutting knives which includes a plurality of anvil members configured to interact intimately with the cutting knives. Also provided is a breakaway feature between the cutting members and a supporting surface defined by the wood processing machine. The supporting surface is relatively smooth, and the cutting knives are mounted to the surface by weldments. If a cutting knife encounters unprocessable foreign material such as metal or rock, the knife breaks away from the supporting surface at the weldment connection, and severe damage to the supporting surface or machine is avoided.

Abstract: A shredder having a hopper for funneling material to the cutting blades of the shredder is provided with a ram assist within the hopper to push material into the cutting blades. The ram is shielded from the material passing through the hopper by an intermediate partial wall extending from the infeed of the hopper to the mid portion of the hopper. In its retracted position the ram is positioned behind the partial wall out of the stream of material passing through the hopper. In its extended position the ram is proximate the outfeed of the hopper within the flow of material. A ram controller senses the load upon the cutting blades of the shredder and selectively activates and deactivates the ram.

Abstract: A control system for a rock crusher in a rock crushing plant operates the crusher at optimum efficiency for increasing the throughput of the crusher. The horsepower of the motor that drives the crusher is sensed, and the level of rock within the crusher bowl is sensed, and these sensed conditions are inputted into a programmable logic controller. The programmable logic controller correspondingly adjusts the feed rate of a feeder that supplies rock to the crusher. The controller also commands a bypass component positioned between the feeder and crusher adjacent the mouth of the crusher for providing an immediately responsive control of the feed rate being delivered to the crusher.

Abstract: A method and apparatus for the two-stage crushing of brittle material comprising a roll mill and a mill connected downstream thereof, the output of the second mill being delivered to a sifter in which a second branch stream of the grit obtained in the sifting operation is returned to the roll mill and a further branch stream is returned to the second mill. A first control circuit keeps the sum of the quantity of fresh material and the quantity of grit constant, while a second control circuit divides the quantity of grit into two branch streams in such a way that the drive power of the roll mill remains constant.