FI76830B - FOERFARANDE FOER ATT TRYCKA EN ROTERANDE SKAERNINGSKNIV MOT EN MATRISSKIVA I EN GRANULERINGS / STYCKETORVSMASKIN. - Google Patents

Description

76830

Method for pressing a rotating cutting blade against a matrix plate in a granulation / peat machine

The invention relates to a method for pressing a rotating cutting blade 5 against a matrix plate in a granulation / peat machine comprising a peat pulp press screw placed in a supply pipe, to the end of which said cutting blade is connected thereto. The invention also relates to an arrangement for carrying out the method in a granulation / peat machine

Current production methods for peat and pellets are based on drying the peat in the field from which it was extracted. The work steps have been combined so that the same 15 machines simultaneously remove, cultivate and apply the raw peat to the field. The machines are used to form raw peat compact, which is intended to be applied as evenly as possible to the field. When the surface of the extrudates dries, it becomes hard and water-repellent. The entire production is dominated by the effort to efficiently dry the 20 extrudates. Matrix plate-based shaping machines are mainly used to produce a compact smaller than normal lump peat size. Due to the smaller diameter of the compact, it dries faster than normal lump peat. The typical diameter of the peat extrudates is -25 and is 50 ... 80 mm and the granule 10 ... 30 mm. The disadvantages of the known machines are the high power demand and the susceptibility of the holes to clogging.

In all known machines, the peat is pressed with a screw in the supply pipe to such a high pressure that it exudes through the nozzle members as a compact. The nozzle members may be, for example, holes in a matrix plate or transverse tube nozzles connected to the cone of a peat machine. A cutting blade belonging to the screw rotates against the nozzle member, which may be either a separate blade welded to the end of the screw or only the sharpened end of the screw. The purpose of this is to cut any fiber bundles and wooden sticks that may be trapped in the nozzle opening 35 into smaller parts.

In practice, the axial alignment of the blade has been found to be an important factor for reliable machine operation. The blade must be substantially backlash-free against the matrix plate 40 or the nozzle cone, respectively, in order to cut the fiber bundles in particular. When play begins to occur due to blade wear, the fibers do not cut across the edge of the opening 2 76830, but the pulp begins to accumulate in the opening, eventually plugging it. In most cases, the user has not corrected the incorrect setting until most of the holes are clogged. In practice, up to several pro-5 cents of machine output is lost, as correcting an incorrect setting has so far been a very big job. Namely, in the most commonly used piece peat machines, the machine has to be dismantled to a considerable extent, since the clearance is removed by an adapter ring 10 placed between the press screw and the output shaft of the bevel gear rotating it. The thickness of this determines the axial position of the press screw and with it the blade.

A solution for removing the clearance is also known, in which the rest of the screw contained in the blade is arranged to be axially movable. This rest of the press-15 ground is arranged in a spring, which thus constantly presses the blade against the matrix plate. In practice, however, no sufficiently rigid spring has been found which, when placed in a small space, would have pressed the blade sufficiently against the matrix plate.

The object of the present invention is to provide a solution 20 for removing the clearance in a practical manner. The features of the method according to the invention are set out in claim 1. By means of the invention, the clearance is automatically removed when the peat mass flow generates an axial force pressing the blade. The features of an arrangement 25 for carrying out a method are set out in claim 2.

In the following, the invention is illustrated by the flow of the accompanying figures, which show an embodiment of the invention.

30 Figure 1 shows a granulating machine with a disc mill and a die plate

Fig. 2 shows the method of mounting the blade at the end of the feed screw. Fig. 3 shows a cross-section of the structure of Fig. 2. The front part of the granulating machine according to Fig. 1 with disc mills is similar to that of the most commonly used peat machines. In the machine according to Fig. 1, the disc mill raises the raw peat on a screw which presses it in the pipe 2 towards and through the matrix plate 1. The matrix plate 1 is firmly attached to the end of the screw tube 2, Figures 2 and 3.

Claims (1)

The end of the screw 4 76330 against the matrix plate also includes a cutting blade 5. The press screw 4 is here floating in the supply pipe, i.e. without the bearing on the side of the matrix plate. The matrix sheet 1 has 28 holes which form the peat mass bursting through into granules. The clamping screw 4 is rotated by the shaft of the bevel gear. The peat mass pushed forward by the screw 4 pushes the screw 4 backwards correspondingly. Figures 2 and 3 show that the shaft 7 of the blade 5 is connected to the shaft 3 of the press screw 4 by means of a straight groove hammer-10 mask coupling 9. This consists of the longitudinal teeth formed in the tube shaft 7 of the blade 5 itself and in the grooves formed in the tube 6, which are arranged together. The tube 6 is welded inside the shaft 3 of the screw 4. The blade 5 must be placed in a direction substantially different from the end 10 of the thread 10 of the screw 4, for example a quarter turn forward. The end 10 of the thread is brought as close as possible to the matrix plate 1 so that the peat mass does not leak behind the thread. The compressive force of the blade 5 against the matrix plate 1 is determined by the mass flow 20