FI66766B - SLAGLISTHAOLLARE FOER ROTORN I EN SLAGKVARN - Google Patents

Description

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Ki C Patent: i cyfn:.: · I ty? 0 1924 ^ Patent ee -Jee la i '* ^ (51) K * .lfc / fc «e.Cl3 B 02 C 13/28 SUOMI — FINLAND (*) r * ~ * »* ~~ -r * mM *** 791277 (22) H« k * mbpilvt— AnaBfcningkbf 19.04.79 (23) Allwpiliii — GlktgMttd · * 19.04.79 (41) TriteHUmU — ttvRcflntiti 03.11.79 rg * »Wjs — asas-eaaBa -j». ··. » FUMIh OCR rt | llivvii] rraiHn amokm Hasp on w.wmi pmoo (32) (33) (31) Ffrfaer * - * - · η · Ν prterlwt 02.05.78 Austria-Österrike (AT) A 3138/78 (71) VOEST -ALPINE Aktiengesellschaft, A-4010Linz, Austria-Austria (AT) (72) Anton Hofer, Liezen, Austria-Austria (AT) (74) Oy Jalo Ant-Wuorinen Ab (54) Impact holder for percussion mill rotor -

This invention relates to a percussion bar holder for an impact mill rotor, wherein the percussion bars are arranged in radially outwardly open notches in the discs mounted on the rotor shaft. the effect is retained in the notch by retaining members mounted on both sides of the strip, which engage in the longitudinal grooves, the front of which is formed as a retaining wedge which engages in a longitudinal groove in the cross-section with a curved shoulder and is freely movable in the notch.

In impact mills, the percussion strips of the rotor entrain the grindable article fed through the feed shaft, which strikes against the impact pieces of the mill case, whereby the article is chopped due to the impact effect. The grinding result then depends on e.g. the shape of the impact strips and the size of the gap between the rotor and the mill housing. However, because the impact bars are subject to severe wear, both their shape and the size of the gap change, which is why the impact bars must be replaced after a certain period of use in order to obtain a roughly uniform grinding result. Nevertheless, in order to make the best possible use of the list material ^> 2 66766, the beat lists are turned over or readjusted before they are replaced. However, this requires a special holder system for impact strips, which causes problems due to the high load on the holders. Thus, for example, it is known (DE-OS 2 105 993) to provide percussion strips with a plurality of longitudinal grooves of circular cross-section in order to provide a post-adjustable holder by means of rods suitable for longitudinal grooves. The radial position of the impact strips thus depends on the longitudinal groove of the impact strip in which the rod is placed. The impact bars are locked in the notches of the rotor receiving them by means of clamping wedges which press the impact bars against the walls of the notches provided with rods. However, the disadvantage of such a structure is that multiple longitudinal grooves result in multiple notching effects, which greatly reduces the load capacity of the impact strips. In addition, the clamping wedges are adjusted by means of adjusting screws, which causes impacts against the adjusting screws, whereby they are correspondingly worn, and in which case it is almost impossible to adjust the clamping wedges by means of screws after prolonged use.

When the percussion strips are made symmetrical with respect to their longitudinal plane due to inversion and are pressed by means of clamping wedges against rotor moldings in the corresponding recesses in the percussion moldings (DE-OS 2 606 000, AT-PS 277 726), in principle the same problems occur. due to the connection.

The object of the invention is to avoid the above-mentioned disadvantages and to improve a percussion bar holder of the above-mentioned type so that the percussion bars can be simply rotated and replaced, that the notching effect is as small as possible and that the percussion bars can be installed without special machining.

The invention solves the set task according to the features of the appended claim 1.

Equipping each percussion bar with only two, preferably semi-circular, longitudinal grooves reduces the notching effect to a minimum. In addition, the free portability of the clamping wedges ensures easy replacement, as the clamping wedges do not have to be adjusted with screws or the like. Also, high stress cannot render the adjusting devices for the clamping wedges unusable. However, despite this free 3 66766 adjustability of the clamping wedges, the impact strips can be fastened without backlash because the corresponding strip-shaped stop of the clamping wedges is located in the longitudinal groove in front of the impact free of play. By arranging the rotary rods on the rear surface of the percussion bars, a parallel torque is generated under the effect of the load of the goods to be ground, so that an increase in the tightening effect can occur at most during use. Thanks to the measures according to the invention, a percussion bar holder is thus obtained in which the percussion bars are fastened without backlash and can be easily replaced, since the clamping wedges are guided from a freely movable position.

According to a further feature of the invention, the length of the circular rods corresponds to the entire length of the rotor, but the clamping wedges are nevertheless arranged in connection with individual discs. Namely, the rotary rods extending over the entire length of the rotor form the axes of rotation of the impact strips in an advantageous manner. However, in order to be able to tighten the impact strips in several places, individual clamping wedges are mounted on each blade of the rotor, which in themselves can be moved until the impact strips are actually in contact. If only a single clamping wedge extending through the rotor were used for each percussion bar, only one-sided fastening would be an issue due to the unprocessed percussion bars.

In order to protect the edges of the notching strips from abrasion in a simple manner, the clamping wedges according to a further feature of the invention can be formed from a second leg of an angular wear piece, the other leg of which preferably covers a recess formed in the circumferential area of the blade. Although the angular shoes protruding over the edges of the notch are already known as wear protection, they have been used as additional structural members in addition to the tightening wedges, which is why combining these fixedly connected shoes with the tightening wedges into one component is not comparable. The wear of the disc-covering part according to the invention does not affect the fastening of the strips.

To prevent the ingress of dust between the branch of the wear cover covering the disc and the disc, which could affect the free displacement of the clamping wedge, a flexible spacer can be fitted between the branch of the wear covering the circumferential part of the disc 4,66766 and the disc.

An example of an embodiment according to the invention is shown in the drawing, in which case

Fig. 1 shows a cross-section of a stroke holder according to the invention as the rotor rotates, and

Fig. 2, respectively, the stroke bar holder when the rotor is stopped.

According to the construction example shown, the rotor of the impact mill comprises at least two discs 2 welded to the pipe 1, the pipe 1 being mounted on the shaft 3 ·

The discs 2 are provided with coaxial notches 5 for fastening the percussion strips 4, on the rear wall of which a round rod 6 extending over the entire length of the rotor is placed in the rear wall. there is a freely sliding clamping wedge 9 with a strip-shaped stop 10 extending into the longitudinal groove 8. This clamping wedge 9 together with the strip-shaped stop 10 is formed by a second leg of an angled wear piece 11, the second leg 12 of which protrudes from the notch 5 and covers the disc 2 by a shoulder 13 formed recess. A flexible spacer 14 is mounted between the leg 12 of the angular wear piece 11 and the disc 2.

Due to the free displaceability of the clamping wedges 9, the impact statistics 4 remain when the rotor is stopped relatively loosely in the notches 5 of the discs 2 and so on. is practically secured only against falling out, as shown in Fig. 2. When the rotor is started, the generated centrifugal force causes the impact strips to move radially outwards, whereby the rotating rod 6 permanently stationary in the rotor forms an axis of rotation. When the percussion strips 4 are then rotated compulsorily, the clamping wedges 9 protrude outwards due to their abutments 10 in their longitudinal groove 8, which together with the rotation of the percussion strips 4 around the round bar 6 causes the percussion strips 4 to fit snugly against the clamping strips 9. The percussion bars are thus fixed as the rotor rotates without backlash, so that the grit accompanying the percussion bars 4 presses the percussion bars 4 even more tightly against the clamping wedges 9, whereby an impact mill equipped with such a percussion bar holder ensures stable conditions during operation.

Claims (4)

1. Impact shelf holder for the rotor in a percussion mill, the impact strip (4) being inserted into radially leaking open cut-outs (5) arranged in the pit rotor shaft (2), which strip in the direction of rotation seen on both the front and rear sides of a semi-circular cross-sectional shape longitudinal cutting (7,8) mirror image arranged in relation to each other, and which strip due to the centrifugal force is retained in the cut-out by means of both sides of the strip arranged in the engaging means (6,9) of the longitudinal cutters, the engagement of which (9) on the front side of the impact strip is formed as a clamping wedge which engages with a beak-shaped stop in cross-section. into the longitudinal cutter on the front is struck by the impact strip and is arranged freely slidable in the cutter, characterized in that the rear pouring member is constituted by a round rod (6) which is formally inserted and in the radial direction immovable retainers in the rotor cutout ( 5) rear wall and forms a pivot shaft for the impact strip (4) around which it swivels while carrying the clamping wedge (9). 2. Impact holder according to claim 1, characterized in that the round bars (6) extend over the entire length of the rotor and that the clamping wedges (9) are arranged adjacent to the individual discs (2). 3. Impact rails according to claim 1 or 2, characterized in that the wedge wedges (9) are formed by