JP2007508920A - Grinding or polishing machine - Google Patents

Abstract

  The present invention relates to a grinding and / or polishing machine with a grinding rotor (4) surrounded by a sieving basket (5) for cereal grains, for example rice, wheat or other grains. The grinding rotor (4) is formed as a hollow shaft (8) and has an opening for the flow of air into the working chamber (14). Air reaches the hollow shaft (8) from the upper and lower air supply sections (9, 10). The working chamber is limited on the product outlet side by a vertically movable weir disc (12). The movability of the weir disc (12) is controlled by a diaphragm drive (13).

Description

  The present invention relates to a grinding and / or polishing machine with a grinding and / or polishing or peeling rotor surrounded by a sieve for cereal grains such as rice, wheat or other cereals.

  Conventional grinding or polishing machines, in particular grinding machines, have an assembly consisting of sieve segments. The sieve segment is assembled at one peripheral edge to the hinge axis, while the other peripheral edge is more or less of the axis so that it enters the chamber filled with the grain to be processed. It can be pivoted to the center. This has the object of providing an increased resistance for the grain seeds entrained by the rotor, with a radially inward adjustment to the free ends of the sieve segments. As a result, friction between the rotor and the grain seeds or friction between the grain seeds occurs.

  When referred to herein as “cereal seeds”, different cereal seeds may apply. Such treatment is used in rice or wheat, but sometimes also in other cereals. Moreover, the application of such machines has already been proposed for coffee beans.

  In order to assist the sieving action and separation of the ground, ground or exfoliated grain grains, the rotor has a hollow shaft through which compressed air is blown into the working chamber. For this purpose, the hollow shaft is connected to a ventilator / compressed air generator.

  In order to achieve a constant product pressure in the working chamber and thus a constant degree of peeling or polishing, a weiring disk (resistive plate) is arranged before the outlet of the working chamber. The weir disc can be adjusted so that a reaction force acts against the product pressure. The reaction force is usually adjusted manually according to experience values via a lever mechanism / link mechanism.

  The object of the present invention is to improve the known structure in such a way that a constant grinding, grinding or peeling of the grain is achieved while avoiding the above drawbacks. The solution to the problem is implemented by the features of the main claim.

  The rotor shaft of the peeling, grinding or polishing machine is a known type and is formed as a hollow shaft having an air flow opening on the peripheral surface, but air is introduced into the hollow shaft from both end surfaces. This allows for even ventilation of the working room. In another advantageous configuration, the rotor shaft is wedge-shaped and the air flow slits are arranged vertically.

  In order to equalize the working capacity of the machine, the use of a toothed belt to drive the rotor shaft also contributes. With less energy requirement and almost zero slip, work capacity is improved.

  The magnitude of the pressing force has a direct influence on the peeling, grinding or polishing degree. On the outside of the working chamber there is a pneumatic diaphragm drive with a force transducer mounted in the axial direction in front of the product outlet. With this arrangement, a constant pressing force on the weir disc can be generated. Thereby, the manual adjustment of the pressing force by the conventional weight is imitated electro-pneumatically.

  This clearly makes it possible to compensate for variations in product pressure as a result of different densities of the product (the weir disc “moves” in response to the product density).

  Thereby, only the pressing force needs to be measured and the constant adjustment of the adjustment weight is omitted. With a more compact dynamic control unit, it is possible not only to control the weir pressure (pressing force) in the operating state more delicately, but also to make the operation of the machine apparently more dynamic. Via the tolerances, the pressing force, the motor current and the pressure controlled in the diaphragm are monitored.

  In particular, by replacing the conventional electric or pneumatic drive device of the weir disc, which is a closing mechanism, with a “drive device” that operates the diaphragm, the dam disc has a small tolerance (narrow range). Having a stepless operation can be achieved. In particular, it is advantageous that the closed position can be kept open in the event of energy failure.

  The pressure of the production logistics against the weir disc creates a force that is compared to the reaction force. This force generated by the product is uninterrupted, ie directly received by a small spring between the lever mechanism and the force transducer and is physically stored during the measuring time of the control. A newly predicted force adaptation or force-related difference based on this system change is compensated via an electrical control valve.

  Thereby, the compressed air in the diaphragm drive and thus the pressing force on the weir disc is adjusted until a balance is again formed. It is exclusively adjusted to a constant pressing force independent of bulk weight.

Further features of the invention result from the following description of the embodiment schematically illustrated in the drawings.
FIG. 1 is a longitudinal sectional view of a vertical grinder according to the present invention.
FIG. 2: A schematic cross-sectional view of a device for controlling the weir pressure.

  The vertical grinding machine 1 has a drive motor 2 for a grinding rotor 4. The transmission of the driving force is realized by a plurality of toothed belts 3. A sieve basket 5 is arranged so as to surround the grinding rotor 4. The sieve basket 5 is connected to a suction part 6 for the soot particles removed by grinding. The grinding rotor 4 has a general grinding tool and a vertically long air flow opening that extends in the axial direction. The grinding rotor 4 is supported on the main bearing 7.

  The grinding rotor 4 is formed as a hollow shaft 8 and has an upper air supply part 9 and a lower air supply part 10. The air supply is performed via one or two ventilators (not shown). As a result of the uniform supply of air over the entire length of the working chamber 14, the grain to be processed does not need to be heated as much and the processing and removal of the straw is carried out more evenly.

  The grinding rotor 4 is lightly wedge-shaped. At that time, the upper diameter is smaller than the lower diameter. Wear is more even.

  In addition, a further bladed rotor with fan action can be provided. The bladed rotor assists the air flow in the working chamber 14.

  Product discharge 11 is carried out from above. The product outlet is closed by a weir disc 12. The damming disk 12 is vertically movable, and the movement of the damming disk 12 is controlled in a closed loop via a diaphragm type driving device 13.

  The diaphragm type driving device 13 may be arranged as shown in the figure, or may be arranged inside the housing of the vertical grinding machine 1. Similarly, the rotor may have a polishing or peeling tool and / or may be arranged horizontally.

  The electronic unit 20 monitors and adjusts the diaphragm drive with the help of the control valve 21. The current pressing force is received by a force transducer 22 and is read by the electronic unit 20. The predetermined pressing force can be preset directly to the device (local) or via a process control system (remote control).

  The lever mechanism 23 controlled pneumatically controls the pressing force depending on the product selected in advance by the electronic unit 20. The small spring 24 receives the lever force change caused by the product. At the same time, the lightly bent spring 24 compensates for the lateral force in the force transducer 22.

  When the motor current exceeds the current limit value determined by the electronic unit 20, the lever mechanism 23 is automatically relieved of load.

1 is a longitudinal sectional view of a vertical grinder according to the present invention. 1 is a schematic cross-sectional view of an apparatus for controlling a weir pressure.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 Vertical grinding machine, 2 Drive motor, 3 Toothed belt, 4 Grinding rotor, 5 Sieve basket, 6 Suction part, 7 Main bearing, 8 Hollow shaft, 9 Air supply part, 10 Air supply part, 11 Product discharge, 12 Weiring disk, 13 Diaphragm type driving device, 14 Working room, 20 Electronic unit, 21 Control valve, 22 Force transducer, 23 Lever mechanism, 24 Spring

Claims (7)

  A grinding, polishing or peeling machine having a working chamber arranged horizontally or vertically, the working chamber being formed between a rotor equipped with a tool and a sieving basket (5). In the type in which the object outlet can be closed by a weir disk (12) and the rotor is formed as a hollow shaft with an air flow opening, the weir disk (12) is a diaphragm type drive device (13 ), A grinding, polishing or peeling machine characterized in that it can be operated steplessly.   Grinding, polishing or peeling machine having a working chamber arranged vertically, the working chamber being formed between a rotor equipped with a tool and a sieve basket (5), and the rotor being air-flowing In the type formed as a hollow shaft (8) with an opening, the hollow shaft (8) has upper and lower air supply parts (9, 10), grinding, polishing or Peeling machine.   The grinding, polishing or peeling machine according to claim 1 or 2, wherein the air flow opening is arranged so as to extend vertically and in the axial direction.   The grinding, polishing or peeling machine according to claim 1 or 2, wherein the rotor is formed in a wedge shape.   The grinding, polishing or peeling machine according to claim 1, wherein the hollow shaft (8) has upper and lower air supply parts (9, 10).   A grinding, polishing or peeling machine according to claim 2, wherein the product outlet of the working chamber can be closed by means of a movable weir disc (12).   The grinding, polishing or peeling machine according to claim 6, wherein the weiring disk (12) is operable by a diaphragm drive (13).

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