EP0103778B1 - Hammer mill - Google Patents

Abstract

In a hammer breaker for breaking and crushing scrap material, particularly scrap metal, in which a hammer rotor having a plurality of hammers pivotally mounted thereon is rotatably mounted about a horizontal axis in a housing having an inlet for the material to be broken and crushed, and an outlet for broken and crushed material at the top of a shaft which is located above the hammer rotor and is arranged to receive material tangentially from the rotor, the outlet being covered by a classifying grate which extends across the top of the shaft, the grate is mounted adjustably, preferably pivotably, relative to the shaft. This enables the effective size of the grate openings through which the broken and crushed material can escape to be adjusted according to the size and density of the scrap lumps required without having to change the grate.

Description

The invention relates to a hammer crusher and to a method for its operation, in particular for crushing old material, consisting of a housing provided with a good inlet, in which a horizontally mounted hammer rotor rotates, and with an impact shaft located above the hammer rotor, which is tangential extends in the direction of rotation of the rotor, and with an outlet grate covering the impact shaft transversely to its axis as a good outlet.

The processing of waste material, e.g. Car bodies and sheet metal scrap with hammer breakers has increased and become more important in recent years. The structural change in crude steel production processes means that scrap trade places ever higher quality requirements on the processed scrap. In the course of these developments, there is also a tendency in scrap trade to demand differently defined piece sizes and densities of the processed material in accordance with the intended purpose of the old scrap.

Hammer crushers are preferably used to process old scrap. A hammer crusher of the type mentioned is known from DE-PS 1 272091. With this hammer crusher, the shredded scrap is shredded by swinging impact hammers, which are attached to a rotor rotating at high speed and strike against - anvils arranged at a distance from the impact circle of the hammers. The free end of each hammer strikes a resilient blow on the material to be shredded within the housing and cuts, tears and shreds it. In this way, for example, a car body or another voluminous sheet metal part is divided into a number of small pieces, which are further reduced in size and compressed by the blows of the hammers. The comminuted material is then thrown off by the hammer rotor or by the hammers directly in the direction of an exchangeable classification grate which covers a shaft located above the hammer rotor and in alignment with a shaft running tangentially to the breaking tools. Due to the impact of the pieces on the walls of the impact shaft and, if necessary, on the classifying grate, the material pre-compressed by the impact hammers undergoes additional compression, so that, for example, fist-sized «nuggets» of high density are created. By exchanging the grate used for another with grate openings of a different size and / or shape, the piece size and density of the material supplied can be changed as far as possible. Thereby, the impact duct plays an important role. Pieces of scrap that do not hit the grate and pieces that hit the grate but, due to their shape and size, their low mass and insufficient kinetic energy, may cannot pass fall back into the baffle and partially collide with the oncoming material thrown up by the impact hammers or they are thrown against the baffle walls and experience an additional compression due to the impact.

Pieces of scrap that are not sufficiently compacted in the impact shaft to pass through the grate openings are further crushed by the impact hammers on the anvil edge at the material inlet and, after this process may have taken place. repeated several times, ejected through the grate. This known hammer crusher essentially works satisfactorily.

However, with this hammer crusher, requirements such as different scrap densities and piece sizes, which the scrap trade places on the finished material, can only be achieved through the optional use of different types of outlet grates with different grate openings, which have to be exchanged for each other in accordance with the shredding result to be achieved. The downtime of the machine associated with each replacement of the grate and the resulting loss of production has an extremely uneconomical effect, especially since the downtimes, depending on the frequency of a necessary grate change given by the desired density or dimension of the material, take on considerable proportions can. This is particularly the case with its nature of strongly changing, heterogeneous old material, which, depending on the different materials to be shredded, accordingly requires different grates or grate openings in order to be able to produce the desired scrap density or dimensions. Another factor that affects profitability is the need to keep a large number of gratings of different designs (opening shape and size) that may need to be used. An additional loss of production occurs with the conventional hammer crusher, as explained below, in that the amount of material shredded per unit of time depends on the wear status of the impact hammers or shredding tools and accordingly a different amount of material to be processed is fed to the hammer crusher and especially the outlet grate for processing. After commissioning the hammer crusher or after changing the tool, the hammer crusher initially works with relatively sharp crushing tools. In the case of new sharp-edged crushing tools, comparatively small-sized material of approximately the same size is first continuously separated from the material fed in, so that A constant amount of material with a defined piece size is fed into the outlet grate at the top, which passes through the grate without any build-up of dust. On the other hand, shredded and worn-out crushing tools only separate or tear off large, coarse pieces from the material to be processed, which are only brought to the required size after repeated circulation in the hammer crusher and repeated compression on the walls of the impact chute and the grate bars of the classifying grate to be able to pass through the grate openings. The prolonged residence time of these pieces of material in the hammer crusher leads to a material jam in the outlet area of the hammer crusher and the resultant reduced production output; Additional side effects include greater wear and tear on the shredding tools and the lining of the hammer breaker, as well as a higher density of the shredded scrap, which is sometimes undesirable.

The invention is based on the object of improving the hammer crusher mentioned at the outset in such a way that it can process materials of different properties to a specific predetermined piece size with the least possible expenditure of energy and time and the size of the pieces corresponding to a certain degree of efficiency, with little wear on the comminution tools and the inner parts Can shred the lining without changing the grate. According to the invention, this object is achieved in that the outlet grate is movably mounted in different positions and is connected to a drive. With a hammer crusher designed in this way, a manipulation with the adjustable, preferably swiveling outlet grate can be used to create a state in which, when in operation, crushed material with the desired piece sizes and required densities is achieved without changing the grate. Whether the shredded material turns out to be more or less dense and smaller or larger is determined by the opening angle of the outlet grille and the projection of the grate openings that varies depending on the effective passage area. The grate openings are aligned with respect to the direction of discharge of the rotor so that when the outlet grate is closed, the cross-section of the grate openings is largest; a crushed, coarse material of relatively low density then arises. When the outlet grate is opened or a larger opening angle is set, the effective projection of the grate openings decreases to an increasing extent, i.e. also at the same time that the resulting material is reduced in size proportionally to the reduction in the projection of the grate openings, while the density increases inversely in proportion.

Due to the possible pivoting of the outlet grate in different positions, the residence time of the materials in the hammer crusher can be changed and thus the production output can be adapted to the desired piece size, whereby a material jam, such as can be caused by worn crushing tools in conventional hammer crushers, is completely avoided.

Possibly coarse parts that can be crushed in the crusher housing and can significantly inhibit the workflow are ejected from the housing by tangential ejection from the impact circle of the hammers after the outlet grate has been completely opened.

In order that during the time during which the coarse parts are ejected from the crusher housing, unnecessarily much usable, comminuted material is also eliminated, in an advantageous further development of the invention the region of the outlet grate that is adjacent to the pivot axis is designed as a grate part that can be pivoted by itself. In this embodiment, the grate part of the outlet grate, which is pivotable per se, lies in the tangential discharge region of the hammer impact circle. The coarse parts thrown up by the hammer rotor to be cut hit the area of the outlet grate, which is pivoted and can be opened if necessary, without the shredded material accidentally leaving the impact shaft. This type of separation of the coarse parts requires only a relatively small opening angle and a small amount of time for the swiveling in comparison with the required pivoting of the complete outlet grate for the separation of the coarse parts.

According to a further development of the invention, the outlet grate covers the shaft at an angle - what e.g. can be achieved by an arc-shaped grate - so that it is ensured that the number or the negative effects of ricochets of reflected material parts are reduced compared to the horizontal arrangement of the grate, which already helps to reduce the risk of an occasional material jam. Due to the higher output and production output, a performance increase of approx. 10-15% compared to conventional hammer crushers is also advantageously achieved.

• Fig.1 einen Hammerbrecher in geschnittener Seitenansicht mit einem in Ruhestellung befindlichen schwenkbaren Auslassrost;
• Fig. 2 eine Alternativausführung mit bogenförmig gekrümmten Auslassrost;
• Fig. eine perspektivische Draufsicht auf den geöffneten Auslassrost nach Fig. 2 und dem damit verbundenen Schacht bei abgenommener Haube;
• Fig. 4 eine Alternativausführung des schwenkbeweglichen Auslassrostes nach Fig. 2, in der Seitenansicht mit für sich schwenkbarem Rostteil;
• Fig.5 eine Stirnansicht des Auslassrostes in Richtung des in Fig. 4 gezeichneten Pfeils V; und
• Fig. 6 einen Querschnitt entlang der Linie VI-VI in Fig. 5.

Further details of the invention are explained below with reference to an embodiment shown schematically in the drawing. Show it:

• 1 shows a hammer crusher in a sectional side view with a pivotable outlet grate in the rest position;
• 2 shows an alternative embodiment with an arched outlet grate;
• Fig. A top perspective view of the open outlet grate of FIG. 2 and there with connected shaft with hood removed;
• FIG. 4 shows an alternative embodiment of the pivotable outlet grate according to FIG. 2, in a side view with a grate part that can be pivoted by itself;
• 5 shows an end view of the outlet grate in the direction of the arrow V drawn in FIG. 4; and
• 6 shows a cross section along the line VI-VI in FIG. 5.

The hammer crusher, designated as a whole by 1, has a housing 2 which is fastened on a base plate 3. In the housing 2, a hammer rotor 4 rotates in the direction of rotation R, the shaft 5 of which is mounted on both sides in bearings, not shown, attached to bearing blocks. The hammer rotor 4 consists of a plurality of rotor disks 6 lined up at a distance on the shaft 5, between which hammers 7 are rotatably mounted on axes 8 which pass through the rotor disks 6 at a radial distance from the shaft 5 and parallel to the latter. The shaft 5 is connected to a drive via a coupling, not shown. A good inlet 9 and a good outlet 10 are provided in the housing 2. The material inlet 9 is located on the downward rotating side of the hammer rotor 4 at the level of the horizontal plane H-H containing the rotor axis x. The upper edge of the material inlet opening 9 is part of an exchangeable anvil 11; the lower edge of the material inlet opening 9 is part of an anvil 12 and is brought up to the hammer impact circle K except for a gap s which results in the desired degree of comminution.

In the area between the material inlet 9 and the material outlet 10, which is located on the side of the housing 2 opposite the material inlet 9, the part of the housing 2 above the hammer rotor 4 is designed as an impact chute 13 open at the top and bottom, the height of which above the center line of the rotor corresponds approximately to the impact circle of the hammer rotor 4. Above, the baffle shaft 13 is covered with a classification grate or outlet grate 14, which is provided with grate openings 19 and extends tangentially to the direction of rotation R of the hammer rotor 4 perpendicular to the axis of the baffle shaft 13 (see FIG. 1). The classifying or outlet grate 14 is mounted so as to be pivotable about a pivot axis 14a. Two hydraulic cylinders 15 - which act on articulated connections 16, 17 on the one hand on the lever 15a and on the other hand are attached to the housing 2 of the hammer breaker 1 or to the hood 18 - are used to open or pivot the outlet grate 14 into the various desired positions can be adjusted to match the required density and piece size. In Fig. Two positions for the outlet grate 14 are shown, with the largest projection b _N resulting in the lower position A - apart from the adjustment of the pivoting position of the grate possible with the invention to achieve a specific density and piece size, one can be added to each Wear of the hammers adjusted grate pivot position can be selected. Position A would be set after the hammers had worn out; in the case of sharp hammers, position B would be set with the smaller projection b _s in order to achieve the required scrap density. Depending on the wear of the hammers and / or the desired piece size of the scrap, positions between positions A and B are of course also possible.

In order to avoid that during the opening pivoting of the grate, uncrushed scrap pieces reach the outside between the free end of the grate and the housing, the upper housing part is designed to be curved in the pivoting area of the grate, so that - using the example of FIG. 1 - between positions A and B the grate travels with its end face along the housing or is only a slight distance from the housing wall, so that a tight seal for shot parts is created. Arranged above the outlet grate 14 is a hood 18 which catches the material thrown out of the grate openings 19, deflects it downward and allows it to emerge out of an opening 20.

In FIGS. 2 and 3, the outlet grate 21 is, in an alternative embodiment to the outlet grate 14 which is horizontally formed and arranged in FIG. 1, preferably curved in an arc shape (arch grate) and covers the baffle shaft 13 obliquely at the top. The outlet grate 21 is provided with grate openings 25. The outlet grate 21 is pivoted about the pivot axis 21a into the respectively desired position by means of two hydraulic cylinders 22, which are fastened to the outlet grate 21 on the one hand and to the hammer breaker housing 2 on the other hand via articulated connections 23, 24, similar to the outlet grate shown in FIG. 5. In this version of the grate as a curved grate, as shown in FIG. 2, the largest opening projection area results in its lowest position. The sealing to be made on the free end face of the grate to the housing wall is carried out as in the exemplary embodiment according to FIG. 1, namely by means of a corresponding circular arc-shaped design of the housing wall in the pivoting area.

In the position of the outlet grate 21 according to FIG. 1, the coarse particles which can possibly be rotating in the crusher housing 2 can be ejected through the impact chute 13 released by the opened outlet grate 21.

The outlet grate 26 shown in FIG. 4, which is also designed as an arch grate, is provided with grate openings 32. The outlet grate 26 comprises a total grate surface 27, from which a grate part 28 that can be pivoted independently can be brought into or pivoted into the position shown in dashed lines in FIG. In FIG. 4, a somewhat open pivot position of the grate 26 is also shown in dashed lines net, whereby it becomes clear that here the sealing on the end face to the housing takes place via a lip 35 cast on at the free end of the grate, which in turn rests against the housing wall, which is in turn circular in shape, in the various working positions.

The lip 35, in particular in its form shown in FIG. 4 - bent back outwards from the inside of the shredder - creates a greater distance between these openings and the housing or hood wall above the grate openings at the end due to the associated recessing of the housing wall. the desired effect for the free passage of the material parts that have been crushed and compacted in the desired manner is optimally used for the already subdivided grate surface. Both grate parts, total grate surface 27 and the independently pivotable grate part 28 are mounted so as to be pivotable about the same pivot axis 26a. The independently pivotable grate part 28 is via a hydraulic cylinder 29 and an articulated connection 31, which is attached to the crusher housing 2 and an articulated connection 31 a, which is attached to the grate part 28, in the desired manner (see also Fig. 5).

If the grate part 28, which is pivotable per se, is to be pivoted with the entire grate surface 27, then the two grate parts 27, 28 are connected to one another as a possible embodiment in the manner resulting from the following description of FIG. 5. Of course, there are also other possibilities, for example by means of bolt locks, but this is not as advantageous as the version shown in FIG. 5.

According to FIG., The grate part 28 (“coarse grate”) and the “residual arch grate” 26 are mounted on the common pivot axis 26a. The arched grate is pivoted by the hydraulic cylinder 30 via a swivel lever 30a on the hub of the arched grate 26, regardless of which the opening or closing of the coarse grate can be effected via the hydraulic cylinder 29 and a swivel lever 29a on the axis 26a. Appropriate limit switches on the hydraulic cylinders ensure that the position of the arch grating 26 corresponds to that of the coarse grating 28 in the respective pivot positions.

This positional correspondence can also be achieved by the cross-sectional shape shown in FIG. 6 for the grate parts, namely namely that the coarse grate 28 is tapered conically towards the inside of the shredder on the three sides movable relative to the outlet grate 26 (see FIG. 6) such that when the opening pivots the outlet grate 26 the coarse grate 28 is automatically taken along. If it is then necessary in any position of the arch grate 27 to let coarse parts out of the interior, the coarse part grate 28 is opened further without difficulty by acting on the hydraulic cylinder assigned to the coarse part grate 28. The return to the overall closed position is also achieved hydraulically, although in individual cases the corresponding action on the hydraulic cylinder assigned to the coarse grate 28 may be sufficient, since in this direction of movement the outlet grate is “taken along” by the coarse grate in this direction of movement.

• Während der Hammerrotor 4 in Drehrichtung R umläuft, wird zu zerkleinerndes Material, z.B. Sperrmüll oder zu verschrottende Autokarosserien, durch den Guteinlass 9 kontinuierlich mittels nicht dargestellter Zufuhrvorrichtungen in den Wirkbereich des Hammerrotors 4 gefördert. Mit dem an der unteren Guteinlasskante angeordneten Amboss 12 als Gegenwerkzeug schneiden oder reissen die Hämmer 7 Materialteile von dem zugeführten Material ab und schleudern die Teile etwa in Pfeilrichtung T tangential in den Prallschacht 13 und zwar im wesentlichen auf den oberhalb des Prallschalters 13 angeordneten bogenförmig gekrümmten Auslassrost 21, der den Schacht 13 über die gesamte Breite schräg zur Abwurfrichtung abdeckt (s. Fig. 3). Dabei verformen sich die aufprallenden Blechteile im Sinne einer Zusammenballung. Materialteile die in den Abmessungen klein genug sind und mit hinreichender Geschwindigkeit genau in die Rostöffnungen geschleudertwerden, passieren den Auslassrost 21 sofort. Ist das Materialteil hingegen zu gross oder hat es nicht genügend kinetische Energie oder schlägt es an den Rost 21 unter einem spitzen Winkel an, dann prallt es an der Rostfläche des Auslassrostes 21 ab und fällt in den Bereich zurück, in dem es von den Hämmern 7 vor dem zweiten Amboss 11 wieder erfasst wird. Am Amboss 11 erfolgt eine weitere Verringerung der Stückgrösse durch Zerkleinerung, an den Wänden 33 und 34 durch Prallbeanspruchung solange, bis die Materialteile die Rostöffnungen 25 bzw. den Auslassrost 21 passieren können. Materialien, die nicht zumindest auf die Grösse der Rostöffnungen 25 des Auslassrostes 21 zerkleinerbar sind, machen sich im Hammerbrecher durch lautes Geräusch bemerkbar. In diesem Fall wird der Auslassrost 21 durch die Hydraulikzylinder 22 in die in Fig. 3 dargestellte, geöffnete Lage verschwenkt, wodurch das durch den Hammerrotor 4 hochgeschleuderte Material den nun nicht mehr abgedeckten Prallschacht passieren kann und nach aussen abgeleitet wird und sodann durch die Haube 18 z.B. auf ein unterhalb der Öffnung 20 angeordnetes, nicht dargestelltes Förderband fällt.

The operation of the hammer breaker according to the invention described above is explained in more detail below with reference to the embodiment according to FIGS. 2 to 5:

• While the hammer rotor 4 rotates in the direction of rotation R, material to be shredded, for example bulky waste or car bodies to be scrapped, is continuously conveyed through the material inlet 9 by means of feed devices (not shown) into the effective area of the hammer rotor 4. With the anvil 12 arranged on the lower edge of the material inlet as a counter-tool, the hammers 7 cut or tear off material parts from the supplied material and hurl the parts approximately tangentially in the direction of arrow T into the baffle shaft 13, essentially onto the arcuately curved outlet grate arranged above the baffle switch 13 21, which covers the shaft 13 obliquely to the direction of discharge over the entire width (see FIG. 3). The impacting sheet metal parts deform in the sense of a cluster. Parts of material that are small enough in size and are thrown into the grate openings with sufficient speed pass the outlet grate 21 immediately. If, on the other hand, the material part is too large or does not have sufficient kinetic energy or if it strikes the grate 21 at an acute angle, it bounces off the grate surface of the outlet grate 21 and falls back into the area in which it comes from the hammers 7 before the second anvil 11 is detected again. The anvil 11 is further reduced in size by crushing, on the walls 33 and 34 by impact loads until the material parts can pass through the grate openings 25 or the outlet grate 21. Materials that cannot be shredded at least to the size of the grate openings 25 of the outlet grate 21 are noticeable in the hammer crusher by loud noise. In this case, the outlet grate 21 is pivoted by the hydraulic cylinders 22 into the open position shown in FIG. 3, as a result of which the material thrown up by the hammer rotor 4 can pass the impact shaft, which is now no longer covered, and is discharged to the outside and then through the hood 18 For example, falls on a conveyor belt, not shown, arranged below the opening 20.

In the alternative embodiment according to the invention according to FIG. 4, the coarse parts are ejected through the open grate part 28, which can be pivoted via the hydraulic cylinder 29 and can be swung out of the total grate surface 27 (see dashed illustration).

After ejection of the un-crushable Grobieiieie by opening the outlet grate 21 and the The grate part 28, the outlet grate 21 or the grate part 28 is closed again and returns to the starting position shown in FIGS. 2 and 4.

If a smaller piece size or denser shredded end material is desired, the outlet grate 21 or the entire grate surface 27 is adjusted with the hydraulic cylinders 22 or 29 with a larger opening angle or swiveled into a position different from the starting position, whereby the material to be shredded due to the changed angle of impact on the grate, the required piece size is given or the desired density is achieved. In addition, in the event of a material jam that may occur over time, the outlet grate 21 can be pivoted or turned on in such a way that material jamming below the grate surface strikes the largest possible cross-section or the largest possible projection of the grate openings 25 and the jam can accordingly be quickly removed again .

Within the scope of the invention, it is also possible for the outlet grate to be provided with oblique grate passages already in the starting position relative to the tangential discharge direction, i.e. pivoting of the grate in the embodiment according to FIG. 2 is possible, for example, to enlarge the effective passages.

Claims (6)

1. Hammer mill, especially for disintegrating waste material, consisting of a housing equipped with a material inlet, in which housing a horizontally journalled hammer rotor revolves, and comprising a baffle shaft situated above the hammer rotor and extending tangentially to the circumferential direction of the rotor, and comprising an outlet grating covering the baffle shaft transversely to its axis as a material outlet, characterized in thatthe outlet grating (14, 21, 26) is mounted movably adjustable into various positions and is connected with a drive (15, 22, 32), so that the opening cross-sections of the outlet grating available to the material for passage in the direction of flight are adjusted for the purpose of influencing the size and/or density of the disintegrated material.

2. Hammer mill according to claim 1, characterized in that the outlet grating is mounted pivotally movable about an axis (14a, 21 a, 26a).

3. Hammer mill according to claim 2, characterized in that the outlet grating (21, 26) is curved to an arc form and obliquely covers the baffle shaft (13).

4. Hammer mill according to one or more of claims 1 to 3, characterized by an outlet grating (26) divided into at least two parts, a grating part (28) adjacent to the pivot axis (26a) being independently pivotal.

5. Hammer mill according to claim 4, characterized in that the independently pivotal grating part (28) is situated in the region of the tangential discharge zone (T) of the hammer rotor (4).

6. Method of disintegrating especially waste material with a hammer mill according to one or more of cliams 1 to 5, wherein parts are separated from the supplied material and are centrifuged against an outlet grating, characterized in that the opening cross-sections of the outlet grating available to the material for passage in the direction of flight are adjusted for the purpose of influencing the size and/or density of the disintegrated material, preferably as a function of the lump size of the material separated at the inlet.

Images