EP2108783A2 - Cutting head base body and cutting head for a heading or a shearing machine and method for their production - Google Patents

Abstract

The base body has a cutting head core (7) and chisel holders (8) consisting a casting workpiece (2), where the chisel holders are molded by a casting mold (1) in a different manner. The cutting head core is designed in a hollow cylindrical shape, and the chisel holders are distributed extensively on an outer casing of the cutting head core. An intermediate ring is provided for the attachment of the cutting head core at adjacent machine parts. The chisel holders comprise recesses that are provided for holding of chisels. An independent claim is also included for a method for manufacturing a cutting head base body for a road heading machine or for a mining machine.

Description

The present invention relates to a cutting head and a cutting head body for a tunneling machine or for a mining machine and a method for producing the cutting head body. Propulsion and mining machines are used, for example, in mining, opencast mining and civil engineering. Cutting heads serve, for example, the creation of trenches in the ground, the breaking up of roads and other sealed surfaces or also the tunneling during tunneling.

From the DE 24 48 753 a cutting head for propulsion and mining machines is known which has a cutting head core of a plurality of annular core discs and an attached Stirnkalotte. On the circumference of the forehead calotte several chisel holders are distributed to which chisels are attached. The chisel holders also serve as conveyor elements. The bit holder are attached to corresponding bit holder approaches on Stirnkalotte by screw, whereby the production of this prior art cutting head requires a lot of effort.

The DE 35 14 446 A1 shows a cutting head of an extraction or driving machine having at its periphery helical, chisel-set webs, the spaces of which serve the material removal. The webs for holding the chisel are welded to the circumference of the cutting head. The welding of the webs proves to be costly, since an accurate positioning of the webs is to ensure.

The DE 33 26 859 C2 shows a multi-part cutting roller for a mining mining machine with an approximately conical facing the excavation end ring and a tubular body, the abboustoßseitig has a larger diameter than the offset side. On the pipe body at least one helical spiral is arranged, which has as well as the closing ring several bit holder for the attachment of Schrißißeln. The tubular body is preferably formed as a casting with the same wall thickness, to which the coil is welded to the bit holders. This weld requires accurate positioning of the coil and bit holders. The production of the welded connection is complicated because it can not be automated. The connection point to be produced is only cumbersome to reach from all sides. Another disadvantage of this known Schrämwalze is that the cutting roller when welding the coil and the chisel holder can forgive up to 5 mm.

The US 2,800,302 relates to a cutting head body for a mining machine, such as a masonry drill or auger. The cutting head body is rotatable about a fixedly coupled shaft. It is made in one piece and has frustoconical openings for attaching chisels. The openings are preferably made using a machine tool, in particular by drilling and extend obliquely to the axis of rotation of the cutting head body. In these openings, the chisels are pressed.

The object of the invention is based on the US 2,800,302 therein, a cutting head body or a cutting head for a propulsion or mining machine provide, for which no increased effort for largely arbitrary arrangement and attachment of the bit holder is required. In addition, it is an object of the invention to provide a method for producing such a cutting head body.

This object is achieved by a cutting head body according to the appended claim 1, a cutting head according to claim 6 and by a method according to the attached independent claim 7.

The cutting head according to the invention is intended for a propulsion or for a mining machine and has a cutting head body with cutting head core and a plurality of differently shaped chisel holders. The chisel holders are used to hold chisels. These may be interchangeable or non-replaceable chisels. According to the invention, the cutting head core and at least several of the bit holder consist of a single cast workpiece. The cutting head according to the invention thus does not have a separately produced connection between the cutting head core and the cast chisel holders, such as a welded or screwed connection, which was produced only after the production of the cast workpiece. This eliminates all additional fasteners between cutting head core and chisel holders. The different shape of the bit holder facilitates demolding of the cast workpiece during its manufacture. The cutting head core and the cast chisel holder are made of the same cast material. In a known manner, the cutting head moreover has one or more active drive units or is connected via power transmission means with a central drive unit of the cutting head supporting construction machine.

The main advantage of the cutting head according to the invention is that it can be produced with little effort and yet has accurately aligned and highly resilient tool holder for receiving the chisel.

In the cutting head according to the invention further chisel holder, for example, in outstanding positions on the cutting head core, be mounted as individual components on the cast workpiece. Preferably, however, all bit holders and the cutting head core consist of a single cast workpiece.

In a preferred embodiment of the cutting head according to the invention, the cutting head core is formed as a hollow cylinder. The bit holders are circumferentially distributed on the outer shell on the cutting head core. Such an embodiment is suitable for propulsion and mining machines with a wide range of applications. However, the cutting head core can also be adapted to other applications, for example by a conical basic shape or by a stepped shape. Likewise, the bit holders may be concentrated on particular areas of the surface of the cutter core.

The bit holders are preferably distributed with a pitch error on an outer shell of the cutter head core, i. the bit holder are not exactly evenly distributed on the outer shell of the cutting head core arranged. Such a design helps to avoid resonances in the operation of the cutting head.

The cutting head according to the invention may comprise further components, for example an intermediate ring for fastening the cutting head core or webs for material removal. Of the Cutting head according to the invention may also comprise a plurality of cutting head body, each having bit holder and together with these consist of a single cast workpiece.

The method according to the invention for producing a cutting head for a tunneling machine or for a mining machine comprises first a step for providing a casting mold for casting a cutting head main body with a cutting head core and with a plurality of differently shaped bit holders. This shape can be a permanent or lost shape. The mold has a cavity which includes the shape of the cutter core to be manufactured, including the bit holders. In a next step, the casting mold is poured with a casting material. The casting material can be introduced by gravity or by a generated overpressure in the mold. Subsequently, a solidification of the cast material, so that a solid cast workpiece is formed. This cast workpiece forms the cutting head body with the differently shaped chisel holders formed thereon. The cutting head core and the cast chisel holders are thus formed by a single cast workpiece. Finally, a demolding of the cast workpiece takes place, in which the casting mold is removed from the cast workpiece.

The particular advantage of the inventive method for producing a cutting head is that the production of the cutting head core and the bit holder can be done in a single step and also the step for connecting the cutting head core can be completely eliminated with the bit holders. The inventive method requires no complex alignment of the bit holder with respect to the cutting head core.

The inventive method preferably includes a post-processing step of the cast workpiece, wherein the surface of the cast workpiece is machined by a machining process, such as milling. Likewise, recesses can be introduced into the bit holder by means of a machining process. These recesses serve for later picking up the chisel. These may be continuous recesses or recesses with a blind hole. The recesses for receiving the chisel can alternatively be achieved by molding in the mold.

The machining process steps are preferably carried out with a CNC machine tool. For this purpose, in particular CNC machine tools are suitable, in which a machining in several levels and multiple axes can be done so that the cast workpiece is only once to clamp in the CNC machine tool. All steps for reworking the surface of the casting workpiece as well as the introduction of all recesses in the bit holder can be carried out automatically by such a CNC machine tool.

The mold is preferably designed as a multipart permanent mold, so that a simple demolding of the cast workpiece can be done. Through the use of multi-part molds detailed shaped chisel holder can be realized. The casting material used is preferably molten steel. However, the method according to the invention is also suitable for other cast materials that meet the requirements with regard to the material of the cutting head.

Fig. 1:

eine Explosionsdarstellung einer Gussform mit einem Gusswerkstück, welches gemäß dem erfindungsgemäßen Verfahren hergestellt wurde;

Fig. 2:

eine Schnittdarstellung der in Fig. 1 gezeigten Anordnung;

Fig. 3:

das in Fig. 1 gezeigte Gusswerkstück in einer Detailansicht; und

Fig. 4:

einen erfindungsgemäßen Schneidkopfgrundkörper, der noch nicht mit Meißeln bestückt ist, in einer perspektivischen Ansicht.

Further advantages, details and developments of the present invention will become apparent from the following description of preferred embodiments with reference to the drawings. Show it:

Fig. 1:

an exploded view of a mold with a cast workpiece, which has been prepared according to the inventive method;

Fig. 2:

a sectional view of in Fig. 1 shown arrangement;

3:

this in Fig. 1 shown cast workpiece in a detail view; and

4:

a cutting head body according to the invention, which is not yet equipped with chisels, in a perspective view.

Fig. 1 shows an exploded view of a mold 01 and a cast workpiece 02, which illustrates a step for removing the cast workpiece 02 according to the inventive method for producing a cutting head. The mold 01 is designed in several parts and comprises a lower case 03, a top case 04 and two filling elements 06. To carry out the method according to the invention, the lower case 03, the upper case 04 and the filling elements 06 are joined together so that they form the casting mold 01. The cavity formed in the casting mold substantially corresponds to the shape of the cast workpiece 02 to be cast. The cavity of the casting mold 01 is possibly slightly larger in size than the workpiece 02 to be produced, in order to enable a later surface treatment of the cast workpiece 02.

Furthermore, the mold does not fill all the later required cavities of a cutting head body to be produced, since these cavities are also created as part of a post-processing. After providing the assembled mold 01, it is filled with molten steel as a casting material. After cooling and solidification of the steel, the cast workpiece 02 is formed. Subsequently, the upper box 04 can be removed from the lower box 03 so that the cast workpiece 02 can be taken out of the lower box 03. Finally, the filling elements 06 are to be taken out of the cast workpiece 02, whereby the casting process is completed.

It should be noted that the casting process described can be performed with different materials or alloys that are selected according to the strength requirements of the cutting head to be produced. Instead of conventional casting, a sintering process could also be selected to make the cutting head body. In particular, for the production of smaller cutting heads is also the production by metal injection process into consideration (MIM - Metal Injection Molding), such methods are still very expensive today. Such and comparable production methods should be covered within the meaning of the invention with the generic term of the casting used here.

The cast workpiece 02 after demolding is a cutting head body consisting of a cutting head core 07 with a plurality of chisel holders 08. The cutting head core 07 and the chisel holder 08 are formed by the single cast workpiece 02 and represent a precursor of a cutting head according to the invention. If necessary, the cast workpiece a Hardening process be subjected.

Fig. 2 shows a sectional view of in Fig. 1 shown arrangement. In particular, the cutting head core 07 with the chisel holders 08 and the corresponding cavities in the lower case 03 and in the upper case 04 of the casting mold 01 are shown. The bit holder 08 are not arranged rotationally symmetrically on the outer shell of the hollow cylindrical cutting head core 07. Instead, the arrangement was chosen such that undercuts on Gusswerkstück 02 are avoided and so the cast workpiece 02 can be produced at a reasonable cost in a casting process. In order to allow such an arrangement of the bit holder 08, the bit holder 08 purposefully different shapes, unlike conventional snow heads, in which the bit holders are welded to the cutting head core. The arrangement and shaping of the chisel holder 08 also facilitates removal of the cast workpiece 02.

Fig. 3 shows the cutting head body 02 in a perspective detail view. In particular, the cutting head core 07 with the plurality of chisel holders 08 is illustrated on the lateral surface of the cutting head core 07. The bit holder 08 have a different shape and an asymmetrical arrangement on the lateral surface. It can be seen that in this embodiment in the chisel holders 08 still no recesses for the attachment of the chisel are available. In modified embodiments, however, such recesses can be produced by appropriate shaping at least in their basic dimensions in the casting process. This reduces the expense of subsequent machining.

Fig. 4 shows the cutting head body 02 after being machined in a CNC machine tool. During the post-processing step in the CNC machine tool Recesses 09 have been milled into the bit holder 08 and made clearances 10. The recesses 09 are used later for picking chisels. Due to the clearances, the simple attachment of the chisel shafts, for example with retaining rings allows.

In modified embodiments, the recesses 09 may be incorporated as blind holes in the bit holders when internal securing possibilities for the bits are used.

The final chisel-occupied cutting head can be used in a tunneling machine or in a mining machine.

LIST OF REFERENCE NUMBERS

01 -

mold

02 -

Cast workpiece / cutting head body

03 -

lower box

04 -

top box

05 -

-

06 -

infill

07 -

Cutting head core

08 -

toolholders

09 -

recesses

10 -

franking

Claims (14)

A cutter head body for a tunneling machine or mining machine comprising a cutter head core (07) and a plurality of bit holders (08), the cutter core (07) and at least one of the bit holders (08) consisting of a single casting (02), characterized in that the bit holders (08) are shaped differently. Cutting head body according to claim 1, characterized in that the cutting head core (07) is formed in a hollow cylindrical shape and the bit holders (08) are distributed circumferentially on the outer surface of the cutting head core (07). Cutting head body according to claim 2, characterized in that the bit holder (08) with a pitch error on the outer surface of the cutting head core (07) are distributed. Cutting head body according to one of claims 1 to 3, characterized in that it further comprises an intermediate ring for fixing the cutting head core (07) to adjacent machine parts. Cutting head body according to one of claims 1 to 4, characterized in that the bit holders (08) have recesses (09) for receiving chisels. Cutting head for a tunneling machine or for a mining machine with a cutting head main body, consisting of a cutting head core (07) and a plurality of chisel holders (08), in each of which a chisel is fixed, characterized in that the cutting head main body is designed according to one of claims 1 to 5. A method of manufacturing a cutting head body for a tunneling machine or mining machine, comprising the steps of: - providing a mold (01) for casting a cutting head core (07) having a plurality of differently shaped bit holders (08); - Pouring the mold (01) with a cast material; - solidifying the casting material to form a cast workpiece (02), which forms the cutting head core (07) with the differently shaped bit holders (08); and - Removal of the cast workpiece (02). A method according to claim 7, characterized in that the cast workpiece (02) is subjected to a hardening process. A method according to claim 7 or 8, characterized in that at least sections of the surface of the cast workpiece (02) is reworked by a machining process. Method according to one of claims 7 to 9, characterized in that in the chisel holders (08) recesses (09) for receiving chisels when pouring the mold (01) are left free. Method according to one of claims 7 to 10, characterized in that after demolding of the cast workpiece (02) recesses (09) for receiving chisels by a machining process in the bit holder (08) are introduced. A method according to claim 9 or 11, characterized in that the machining process is performed by a CNC machine tool. Method according to one of claims 7 to 12, characterized in that the casting mold (01) is designed in several parts. Method according to one of claims 7 to 13, characterized in that the casting mold (01) is poured with molten steel as a casting material.

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