EP2851123B1 - Hammer crusher grate - Google Patents

Description

The invention relates to a hammer crusher grate. Such a hammer crusher grate is part of a hammer crusher, also called a hammer mill, that is to say a comminution machine which is used, for example, for industrial raw material preparation, but also for comminuting valuable materials (residual materials).

The central element of such a hammer crusher is a rotor with a horizontally arranged shaft and rotating shredding tools (hammers) that act on the material to be shredded. Their crushing effect is primarily based on the impact and impact loads on the feed material by the hammers articulated on the rotor. Such a hammer crusher is for example from the US 6,371,393 B1 known.

Hammer crushers can have one or more rotors, which are usually arranged centrally in the crusher workspace. The explanations below relate to a single-shaft hammer crusher (according to US 6,371,393 B1 ), can also be transferred analogously to hammer crusher with several rotors.

The feed material, which is crushed by the hammers, is then shredded on the one hand via grates and on the other hand led out of the machine. With the from the US 6,371,393 B1 Known hammer mill these are a so-called bottom grate (below the rotor) and a so-called top grate (above the rotor).

While the bottom grate is curved, following the cylindrical shape of the rotor, the top grate, which runs at a distance above the rotor, has essentially the shape of a cuboid.

The WO 90/00933 A1 shows a hammer crusher in which a top grate is slidably arranged by means of a piston / cylinder unit. From the WO 2010/103241 A1 a foldable grate is known for a hammer mill. The FR 2382269 A shows a top grate for a hammer mill, which can be slid into the desired position. The EP 0 624 445 A1 describes a hammer mill with top grate, which lies on a frame.

The prior art and the invention are described in more detail below with the aid of such a rectangular top grate, but can also be applied analogously to other geometrical forms of grates.

In a top view, the top grate thus has a rectangular shape and is characterized by two outer long sides and two outer broad sides.

• Durch die ständige Schlagbeanspruchung während des Betriebes und/oder Verunreinigungen kann sich die Position des Oberrostes verändern, so dass der Oberrost am Oberteil der Hammermühle zumindest temporär "anhaftet".
• Als Material für den Oberrost wird häufig Mangan-Hartstahl verwendet, ein Material mit sehr hoher Zähigkeit und Verschleißfestigkeit, allerdings mit dem Nachteil, dass der Werkstoff unter Schlagbeanspruchung "wächst", und zwar insbesondere durch eine verformungsinduzierte Martensitbildung. Dabei kann das Material um bis zu drei Vol.-% "wachsen" (sich ausdehnen).

In the prior art, the top grate with its outer long sides and broad sides lies loosely on corresponding sections of the housing of the hammer breaker. Since the top grate is a wearing part, it must be replaced regularly. For this, the from the US 6,371,393 B1 known hammer mill the upper part of the hammer mill opened to provide access to the top grate. It can happen that the top grate is lifted / shifted at least over a certain distance and then falls back into the hammer mill in an uncontrolled manner. There are two main reasons for this:

• The position of the top grate can change due to the constant impact stress during operation and / or contamination change so that the top grate "sticks" to the top of the hammer mill at least temporarily.
• Manganese hard steel is often used as the material for the top grate, a material with very high toughness and wear resistance, but with the disadvantage that the material "grows" under impact stress, in particular due to deformation-induced martensite formation. The material can "grow" (expand) by up to three% by volume.

This growth can also cause the upper grate to jam on the upper part, which is undesirable.

The described material property of manganese hard steel also has the disadvantage that mechanical stresses are induced in the grate by the growth of the material if the grate is arranged within a fixed receptacle or in particular if the grate itself is fixed in place.

• Der Rost soll sicher und formstabil sein.
• Der Rost soll verschleißbeständig sein.
• Mechanische Belastungen des Rostes außerhalb der Schlagbeanspruchung durch das zu zerkleinernde Material sollen weitestgehend vermieden werden.
• Der Rost soll sicher positionierbar und sicher austauschbar sein.

The object of the invention is to eliminate these disadvantages and to offer a hammer crusher grate which has as many of the following properties as possible:

• The grate should be safe and stable.
• The grate should be wear-resistant.
• Mechanical stresses on the grate outside the impact stress from the material to be shredded should be avoided as far as possible.
• The grate should be securely positioned and securely replaceable.

The invention is based on the following considerations:
The disadvantages of known grates described above can be avoided if the grate is stored specifically in or on the housing of the associated hammer mill.

Basically, it would be sufficient to secure the cuboid grate (in particular at one of its four corner areas) with a fixed bearing and otherwise leave enough clearance between the outer long sides and broad sides and corresponding housing sections of the hammer breaker to allow the grate to move under the impact stress these free spaces can grow into the grate without inducing any mechanical stress from the housing of the hammer breaker.

In this embodiment, however, the expansion behavior and in particular the direction of the expansion would be largely uncontrollable. The grate could rotate around the fixed bearing in the grate plane, which is undesirable.

The invention therefore proposes an embodiment which, in addition to the fixed bearing mentioned, provides at least one floating bearing which allows the grate to move in one direction of the coordinate system, but reliably prevents undesired rotation of the grate in the hammer mill. The position (orientation) of the grate is completely preserved within technical tolerances. It is only necessary to ensure that there is enough space parallel to the long and / or wide sides so that the grate can grow into these rooms without running into stops or counter bearings.

• Einer Rechteckform in einer Aufsicht,
• zwei äußeren Längsseiten und zwei äußeren Breitseiten,
• einer ersten Einrichtung, die einen Teil eines Festlagers bildet, mit dem der Hammerbrecher-Rost an einem Gehäuse eines zugehörigen Hammerbrechers befestigt werden kann,
• einer zweiten Einrichtung, die einen Teil eines ersten Loslagers bildet, entlang dem der Hammerbrecher-Rost am Gehäuse des Hammerbrechers beweglich in Richtung der Längsseiten oder Breitseiten geführt werden kann.

In its most general embodiment, the invention then relates to a hammer crusher grate with the following features:

• A rectangular shape in a top view,
• two outer long sides and two outer broad sides,
• a first device which forms part of a fixed bearing with which the hammer crusher grate can be fastened to a housing of an associated hammer crusher,
• a second device, which forms part of a first floating bearing, along which the hammer crusher grate on the housing of the hammer crusher can be moved in the direction of the long sides or broad sides.

In one embodiment, the top grate comprises a third device, which forms part of a second floating bearing, along which the hammer breaker grate can be guided on the housing of the hammer breaker in a direction that is perpendicular to the direction of movement that the second device enables.

In other words: the hammer crusher grate is secured and positioned via two or three bearings in the hammer crusher housing. The fixed bearing serves as a safeguard against unintentional loosening. The fixed bearing prevents, for example, that the grate is inadvertently moved (raised) when the machine is opened, or that the grate rotates in the storage level.

The floating bearing or bearings have the task of ensuring that the grate grows tension-free in two mutually perpendicular directions within the main surface of the grate.

The fixed bearing does not necessarily have to be free of play. Rather, for example to facilitate the assembly of the grate, it will allow a certain amount of play within the usual tolerances, for example a movement of a maximum of 10 mm in each direction of the coordinate system, alternatively a maximum of 7 mm, a maximum of 5 mm or a maximum of 3 mm.

At least one of these devices can be arranged along an outer long side or outer broad side. This embodiment is also preferred, although not absolutely necessary, because one or more devices could in principle also be provided, for example, in the middle of the grate.

As illustrated in the following drawing, an embodiment is possible in which all three devices are arranged along the outer long sides and / or broad sides.

According to a further embodiment, the first device is arranged in the end region of a broad side or in the end region of a long side, for example in the corner region between a broad side and a corresponding long side.

The second device or the third device are preferably arranged at a distance from the first device, in particular when the length of the linear mobility of the grate made possible by the device is limited. In this respect, the mentioned distance from the first device should correspond, for example, to at least half the maximum extent of the corresponding broad side or long side. This also corresponds to the following description of the figures.

The facilities can be designed differently. In principle, the devices must cooperate with corresponding devices, which are provided in particular on the housing of the hammer mill. Typically, part of the facility is a so-called "male part" (English: "male part") and the corresponding part is a "female part" (English: "female part").

This includes tongue and groove designs as well as "pin / hole" connections, plug connections, bayonet locks or the like.

According to a first embodiment, the first device consists of a hole or a pin. If the grate is designed with a hole, an associated pin is provided on the housing, which engages in the hole so that both take over the fixed bearing function in cooperation.

The term hole / pin includes screw / thread connections, in particular also those with a "head" in order to secure the grate in the vertical direction.

The second device, the third device or the second and the third device can analogously consist of a longitudinal hole or a pin. The elongated hole has the desired orientation in which the grate should be "movable", the position of the pin shifting analogously within the elongated hole during the movement process.

From the above-described function and mode of operation of the hammer crusher grate with the devices mentioned it follows that the longitudinal hole preferably has a minimum length in the longitudinal direction should correspond to the maximum expected expansion of the hammer crusher grate in this longitudinal direction under operating conditions.

For a hammer crusher grate made of manganese hard steel, for example, the typical maximum elongation is three to four vol.%. With an extension of one long side of the grate of 3,000 mm, this corresponds to a longitudinal hole with a minimum length between 90 and 120 mm. Of course, the longitudinal hole can also have a greater length; to this extent, only the maximum extension of the corresponding long side or broad side gives a constructive limit.

As explained above, the floating bearings in the area of the second and third device merely have a “guiding function” in order to ensure the stress-free expansion of the rust material in the corresponding direction.

Further features of the invention result from the features of the subclaims and the other application documents.

Figur 1:

einen Vertikalschnitt durch einen Hammerbrecher mit einem erfindungsgemäßen Hammbrecher-Rost

Figur 2:

eine dreidimensionale Ansicht des Hammerbrecher-Rostes gemäß Figur 2.

Figur 3:

eine Aufsicht des Hammerbrecher-Rostes gemäß Figur 1

Figuren 4a bis c:

verschiedene Ansichten des Oberrostes gemäß Figur 2 im eingebauten Zustand

The invention is explained in more detail below using an exemplary embodiment. Here show - each in a schematic representation -

Figure 1:

a vertical section through a hammer crusher with a hammer crusher grate according to the invention

Figure 2:

a three-dimensional view of the hammer crusher grate according Figure 2 .

Figure 3:

a supervision of the hammer crusher grate according to Figure 1

Figures 4a to c:

different views of the top grate according to Figure 2 when installed

The in Figure 1 The hammer crusher shown corresponds generically to the hammer crusher US 6,371,393 B1 , so that only the most important parts of the system are explained below and reference is made to the disclosure of the US patent.

The machine consists of three parts, a lower part H1, a middle part H2 and an upper part H3. The upper part H3 can be pivoted about a joint G in the direction of arrow P. When the upper part H3 is open, a top grate 10 of the system is accessible, the details of which can be found in the Figures 2 to 4 result and are explained in more detail below.

At a distance below the top grate 10, a rotor R with (not shown) vibrating hammers can be seen, that is to say the comminution unit. Below the cylindrical rotor R there is an undergrate U which runs parallel to a section of the peripheral surface of the rotor R.

A feed opening Z for the material to be shredded, here: automobile bodies, can be seen to the right above the rotor R.

The invention relates in principle only to large industrial plants or their parts.

The top grate 10 according to Figure 2 has an approximate cuboid shape. In the supervision there is a rectangle. The grate accordingly has two outer long sides L1, L2 and two outer broad sides B1, B2, which frame a grid-like grate structure, which in turn is perpendicular to one another extending webs 12, 14, the grid openings 16 limit. The webs 12 run at an angle of 20 ° to the Z direction.

How Figure 2 shows the long sides L1, L2 consist of two parallel sheets L1.1, L1.2.

In the end region of the long side L1, specifically in the corner region to the broad side B2, the sheets L1.1, L1.2 are each provided with a circular hole 18.1, 18.2. The holes 18.1, 18.2 are vertically aligned with one another. They form a first device E1, which forms part of a fixed bearing, with which the hammer crusher grate 10 can be fastened to a housing GH of the hammer crusher, like that Figures 4a to c show and will be explained in more detail below.

At a distance from the holes 18.1, 18.2, elongated holes 20.1, 20.2 are arranged in the sheets L1.1, L1.2, in a manner that is vertically aligned with one another, analogously to the holes 18.1, 18.2. The longitudinal extension of the elongated holes 20.1, 20.2 runs in the Y direction. The elongated holes 20.1, 20.2 form a second device E2 as part of a first floating bearing.

In the end region of the outer longitudinal side L2, approximately opposite the holes 18.1, 18.2, two further elongated holes 22.1, 22.2 are arranged in sheets L2.1, L2.2. The long side L2 is designed analogously to the long side L1, as can be seen in particular from FIGS Figures 4a to c results.

The elongated holes 22.1, 22.2 also form a third device as part of a second floating bearing. They are vertically aligned with one another, but they have their greatest extent in the X direction, as in particular Figure 3 shows.

The Figures 4a to c show the top grate 10 in the installed state.

For this purpose, the hole 18.2 is fastened to the housing GH of the hammer crusher by means of a screw SC (shown only symbolically). Hole 18.2 and screw SC accordingly form the fixed bearing for fastening the top grate 10 within the hammer crusher.

In the area in which the elongated hole 20.2 of the sheet metal L1.2 lies on the housing GH, a pin ST1 extends from the housing GH through the elongated hole 20.2 upwards ( Figure 4c ), so that slot 20.2 and pin ST1 together form a first floating bearing. This floating bearing allows the top grate 10 to move in the Y direction independently of the fixed bearing 18.2 / SC.

An analogous pin arrangement ST2 results in the area of the elongated hole 22.2, the pin ST2 and elongated hole 22.2 allowing the top grate 10 to move in the X direction on the housing GH due to the alignment described.

The fixed bearing consisting of screw SC and hole 18.2 ensures that the top grate 10 remains unchanged in its functional position, even if the top part H3 of the system is opened around the joint G.

The floating bearings (20.2, ST1; 22.2, ST2) ensure that expansions of the material (mangnesite hard steel) of the top grate 10 can be compensated for under impact stress by moving the grate along the elongated holes 20.2, 22.2.

The pins ST1, 2 or the screw SC can through the corresponding holes 18.1, 18.2; 20.1, 20.2, 22.1, 22.2 be led through; otherwise the holes 18.1, 20.1, 22.1 also serve for easier assembly.

Claims (12)

1. Hammer crusher grate with the following features:

   (a) a rectangular shape in a top view;

   (b) two outer longitudinal sides (L1, L2) and two outer broad sides (B1, B2);

   (c) a first device (E1) which forms part of a fixed bearing for fixing the hammer crusher grate to a housing (GH) of an associated hammer crusher;

   (d) a second device (E2) which forms part of a first movable bearing, along which the hammer crusher grate can be movably guided on the housing (GH) of the hammer crusher in the direction of the longitudinal sides (L1, L2) or the broad sides (B1, B2).
2. Hammer crusher grate according to claim 1, with a third device (E3) which forms part of a second movable bearing along which the hammer crusher grate can be movably guided on the housing (GH) of the hammer crusher in a direction perpendicular to the direction of movement of the first movable bearing.
3. Hammer crusher grate according to claim 1 or 2, in which at least one device (E1, E2, E3) is arranged along an outer longitudinal side (L1, L2) or outer broad side (B1, B2).
4. Hammer crusher grate according to claim 1 or 2, in which all devices (E1, E2, E3) are arranged along the outer longitudinal sides (L1, L2) and broad sides (B1, B2).
5. Hammer crusher grate according to claim 1 or 2, in which all three devices (E1, E2, E3) are arranged along the outer longitudinal sides (L1, L2) or broad sides (B1, B2).
6. Hammer crusher grate according to claim 1, in which the first device (E1) is arranged in the end region of a broad side (B1, B2) or in the end region of a longitudinal side (L1, L2).
7. Hammer crusher grate according to claim 1, wherein the first device (E1) is arranged in the corner region (L2-B1; B1-L1; L1-B2; B2-L2) of a broad side (B1, B2) with a corresponding longitudinal side (L1, L2).
8. Hammer crusher grate according to claim 1 or 2, in which the second device (E2) and/or the third device (E3) are arranged at a distance from the first device (E1) which corresponds to at least half of the maximum extension (EB, EL) of the corresponding broad side (B1, B2) or longitudinal side (L1, L2).
9. Hammer crusher grate according to claim 1, in which the first device (E1) consists of a hole (18.1, 18.2) or a pin.
10. Hammer crusher grate according to claim 1, in which the second device (E2), the third device (E3) or the second and third devices (E2, E3) consist of an elongated hole (20.1, 20.2; 22.1) or a pin.
11. Hammer crusher grate according to claim 10, in which the elongated hole (20.1, 20.2; 22.1) in the longitudinal direction has a minimum length which corresponds to the maximum expected elongation of the hammer crusher grate in this longitudinal direction under operating conditions.
12. Hammer crusher grate according to claim 1 made of manganese cast iron.

Images