A medicine grinder has a grinding assembly having a ring burr and a frustoconical burr being mutually rotatable relative to each other. The ring burr is tubular. The frustoconical burr is disposed within the ring burr and has multiple rough grinding edges, multiple recesses, and a non-grinding portion. The multiple rough grinding edges surround a center of the frustoconical burr. Each one of the grinding edges spirally extends about the center of the frustoconical burr. The multiple recesses are divided by the multiple rough grinding edges. One of the multiple recesses has a capacity being larger than a capacity of each one of the other recesses to define a non-grinding portion. Therefore, multiple receiving spaces are formed between the frustoconical burr and the ring burr.

A powder gathering apparatus includes at least two rotating plates and a driving mechanism. The at least two rotating plates are disposed with respect to each other. Each of the rotating plates includes at least one spherical member. The at least one spherical member protrudes from the rotating plate. The driving mechanism drives at least one of the at least two rotating plates to move, such that the at least two rotating plates get close to or away from each other. The driving mechanism drives the at least two rotating plates to rotate.

A powder gathering apparatus includes at least two rotating plates and a driving mechanism. The at least two rotating plates are disposed with respect to each other. Each of the rotating plates includes at least one spherical member. The at least one spherical member protrudes from the rotating plate. The driving mechanism drives at least one of the at least two rotating plates to move, such that the at least two rotating plates get close to or away from each other. The driving mechanism drives the at least two rotating plates to rotate.

An experimental device for SDC of powder particle sizes in a disc mill system includes a screw feeding control device, a mill speed adjustment device, a disc gap servo control device, a sampling device, a laser particle analyzer, a control cabinet and an upper computer. A control method for the experimental device includes the following steps: 1) performing initial setting; 2) starting the disc mill system; 3) performing sampling through a sampling device; 4) detecting a actual PDF (probability density function) shaping of distribution of powder particle sizes through the laser particle analyzer; and 5) updating the initial setting through a SDC algorithm. The experimental device and method can verify a series of SDC algorithms, and provides good a better experimental platform for teaching and scientific research; and the shape of non-Gaussian distribution of output random variables of a stochastic distribution system can be effectively controlled.

An experimental device for SDC of powder particle sizes in a disc mill system includes a screw feeding control device, a mill speed adjustment device, a disc gap servo control device, a sampling device, a laser particle analyzer, a control cabinet and an upper computer. A control method for the experimental device includes the following steps: 1) performing initial setting; 2) starting the disc mill system; 3) performing sampling through a sampling device; 4) detecting a actual PDF (probability density function) shaping of distribution of powder particle sizes through the laser particle analyzer; and 5) updating the initial setting through a SDC algorithm. The experimental device and method can verify a series of SDC algorithms, and provides good a better experimental platform for teaching and scientific research; and the shape of non-Gaussian distribution of output random variables of a stochastic distribution system can be effectively controlled.

There is disclosed a refiner segment (10) for a refiner (1) of lignocellulosic material. The refiner segment (10) is part of a refiner disc (100) that comprises a center area (11). The refiner segment (10) comprises a number H, N2, of bar zones (Z.sub.i,i=1, 2, . . . N) that are arranged at different radial positions with regard to a radial direction R extending from the center area (11) of the refiner disc (100)_towards the periphery of the refiner segment (10). Each of the bar zones (Z.sub.i) are defined by a corresponding set of refining bars (Z.sub.i.sup.RBi, i=1, 2, . . . M) that are distributed angularly and encircles the center area (11). The refining bars (Z.sub.i.sup.RBi) belonging to different but neighboring bar zones (Z.sub.i, Z.sub.i+1) are angularly offset and refining bars (Z.sub.i.sup.RBi) belonging to different but neighboring bar zones are arranged in such a way that a tangential direction of a particular refining bar (Z.sub.k.sup.RBk) belonging to a bar zone (Z.sub.i,) points in a direction towards the mid-point between two refining bars (Z.sub.k+1.sup.RBk+1) belonging to a neighboring bar zone (Z.sub.i, Z.sub.i+1) and wherein the length of refining bars belonging to different bar zones decreases from a largest length for refining bars (Z.sub.i.sup.RBi) belonging to the innermost bar zone (Z.sub.1), with regard to the center (11) of said refining disc (100), to the smallest length for refining bars (Z.sub.N.sup.RBN) belonging to the outermost bar zone (Z.sub.N) adjacent the periphery of said refiner segment (10). There is also disclosed a rotor disc comprising such a refining segment, a stator disc adapted to cooperate with such a rotor disc as well as a refiner comprising at least one of such a rotor disc and stator disc.

There is disclosed a refiner segment (10) for a refiner (1) of lignocellulosic material. The refiner segment (10) is part of a refiner disc (100) that comprises a center area (11). The refiner segment (10) comprises a number H, N2, of bar zones (Z.sub.i,i=1, 2, . . . N) that are arranged at different radial positions with regard to a radial direction R extending from the center area (11) of the refiner disc (100)_towards the periphery of the refiner segment (10). Each of the bar zones (Z.sub.i) are defined by a corresponding set of refining bars (Z.sub.i.sup.RBi, i=1, 2, . . . M) that are distributed angularly and encircles the center area (11). The refining bars (Z.sub.i.sup.RBi) belonging to different but neighboring bar zones (Z.sub.i, Z.sub.i+1) are angularly offset and refining bars (Z.sub.i.sup.RBi) belonging to different but neighboring bar zones are arranged in such a way that a tangential direction of a particular refining bar (Z.sub.k.sup.RBk) belonging to a bar zone (Z.sub.i,) points in a direction towards the mid-point between two refining bars (Z.sub.k+1.sup.RBk+1) belonging to a neighboring bar zone (Z.sub.i, Z.sub.i+1) and wherein the length of refining bars belonging to different bar zones decreases from a largest length for refining bars (Z.sub.i.sup.RBi) belonging to the innermost bar zone (Z.sub.1), with regard to the center (11) of said refining disc (100), to the smallest length for refining bars (Z.sub.N.sup.RBN) belonging to the outermost bar zone (Z.sub.N) adjacent the periphery of said refiner segment (10). There is also disclosed a rotor disc comprising such a refining segment, a stator disc adapted to cooperate with such a rotor disc as well as a refiner comprising at least one of such a rotor disc and stator disc.

A center plate for a rotor in a pulp refiner has a surface provided with at least one feeding wing for directing lignocellulose-containing material towards a periphery. The feeding wing is an elongated protrusion arranged such that its second end is arranged further away from a center of the center plate than a first end and also is displaced relative to the first end in a direction opposite to a direction of rotation of the rotor. The center plate is also provided with at least one counter-feeding wing for directing steam flowing along the surface towards the center of the center plate. The counter-feeding wing is an elongated protrusion arranged such that a second end of the counter-feeding wing is arranged further away from the center of the center plate than a first end and closer to the center of the center plate than the first end.

A center plate for a rotor in a pulp refiner has a surface provided with at least one feeding wing for directing lignocellulose-containing material towards a periphery. The feeding wing is an elongated protrusion arranged such that its second end is arranged further away from a center of the center plate than a first end and also is displaced relative to the first end in a direction opposite to a direction of rotation of the rotor. The center plate is also provided with at least one counter-feeding wing for directing steam flowing along the surface towards the center of the center plate. The counter-feeding wing is an elongated protrusion arranged such that a second end of the counter-feeding wing is arranged further away from the center of the center plate than a first end and closer to the center of the center plate than the first end.

A refiner segment configured to be attached to a refiner disc in a refiner of lignocellulosic material includes: a plurality of bars extending in a direction from an inner periphery of the refiner segment towards an outer periphery of the refiner segment; a plurality of intermediate areas, each intermediate area disposed between adjacent bars of the plurality of bars and configured to separate each bar from an adjacent bar, wherein at least one of the intermediate areas includes: a channel region having a first side and extending a first depth into the refiner segment, and a ridge region connected to the first side of the channel region and extending a second depth into the refiner segment less than the first depth. The channel region has a width W.sub.1 that gradually decreases in a direction from the outer periphery of the refiner segment toward the inner periphery of the refiner segment, and the ridge region has a width W.sub.2 that correspondingly increases in the direction from the outer periphery of the refiner segment toward the inner periphery of the refiner segment.