The present invention relates to a milling tooth for a comminution machine, according to the preamble of claim 1, a milling tooth holder according to the preamble of claim 16 and a comminution machine according to the preamble of claim 17.
Milling teeth in the form of brush cutter flails or the like for earth working machines, such as mowers, choppers or mulchers, are disclosed by U.S. Pat. No. 3,678,671, DE 199 51 086 or EP 0 182 122, for example. These milling teeth are generally mounted in a sprung manner on a rotating drum, so that sudden mechanical effects or shocks on account of stones or the like do not lead to immediate destruction of the milling teeth involved. However, the desired action is limited, particularly in the case of hard materials such as wood, because of the springing.
The invention is based on the object of improving a milling tooth, a milling tooth holder and a comminution machine of the abovementioned type with respect to the relationship between costs and service life, that is to say with respect to economy.
According to the invention, this object is achieved by a milling tooth of the abovementioned type having the features identified in claim 1, by a milling tooth holder of the abovementioned type having the features identified in claim 16 and also by a comminution machine of the abovementioned type having the features identified in claim 17. Advantageous refinements of the invention are described in the further claims.
In a milling tooth of the abovementioned type, the invention provides for the flange side to be formed on the milling tooth body opposite the working side, for an entire side of the milling tooth body which is oriented in the working direction, to be formed as the working side, for the milling tooth tip to project beyond the flange side in the direction of a longitudinal axis of the milling tooth body, perpendicular to the working direction, and for a first section of the milling tooth body to project beyond the flange side in a direction parallel and opposite to the working direction.
In a milling tooth holder of the abovementioned type, the invention provides for said holder to have a flange side pointing in the working direction for fixing the milling tooth with an elevation and, adjacent to the flange side, to have a flat section in such a way that the first section of the milling tooth is supported on this flat section.
This has the advantage that, in a surprising way, a particularly long service life of the milling tooth is achieved. By means of the section projecting beyond the flange side in a direction parallel and opposite to the working direction, the milling tooth is supported on the milling tooth holder. At the same time, particularly high shear forces in the region underneath the projecting section are avoided, since the entire milling tooth body on the working side is acted on by forces and not merely the region of the projecting milling tooth tip above the milling tooth base. By means of the arrangement and formation according to the invention of the flange side of milling tooth and milling tooth holder, particularly good and uniform dissipation of forces from the milling tooth to the milling tooth holder is achieved, pressure peaks in the milling tooth body being avoided, above all at the transition from the milling tooth base to the milling tooth tip.
The section projecting beyond the flange side in a direction parallel and opposite to the working direction is expediently a part of the milling tooth tip.
Greater strength and durability of the milling tooth is achieved by the milling tooth tip having a smaller width than the milling tooth base.
The greatest possible contact area between milling tooth body and milling tooth holder with little lateral play is achieved by an oval recess being formed on the flange side for the engagement of an oval elevation on the milling tooth holder.
In a particularly preferred embodiment, starting from the cutting device in the direction of the milling tooth base, a predetermined second section of the working side of the milling tooth tip is of linear design and is tilted by a predetermined first angle, for example 10 degrees to 14 degrees, in particular 12 degrees, with respect to a longitudinal axis of the milling tooth body. On the working side of the milling tooth body, between the milling tooth base and the second section, a third section with a predetermined curvature is formed, for example with a radius of curvature of 50 mm to 70 mm, in particular 60 mm. A dividing plane between milling tooth base and milling tooth tip is is tilted with respect to a longitudinal axis of the milling tooth body by a predetermined second angle of, for example, 90 degrees to 110 degrees, in particular 100 degrees. The first section projects beyond the flange side by 30 mm to 40 mm, in particular by 33.4 mm. The milling tooth tip projects beyond the flange side by 60 mm to 90 mm, in particular by 78 mm. The first section has a height of 20 mm to 40 mm, in particular of 29.5 mm. The milling tooth tip has a width of 15 mm to 30 mm, in particular of 23 mm. The milling tooth base has a width of 50 mm to 60 mm, in particular of 55 mm.
The invention will be explained in more detail below using the drawing, in which:
The preferred embodiment shown in FIGS. 1 to 3 of a milling tooth 10 according to the invention for a comminution machine, not shown in its entirety, comprises a milling tooth body with a flange side 12 for detachable connection to a milling tooth holder of the comminution machine, a recess 14, a milling tooth tip 16 on the side of the recess and a milling tooth base 18 on the end facing away from the milling tooth tip 16. Arranged in the recess 14 is a cutting device 20 in the form of two hard metal parts. These hard metal parts are, for example, soldered into the recess 14. Accessible from the flange side 12, in the milling tooth body, there are two threaded holes 22, by means of which a braced fastening to the milling tooth holder is carried out. For this purpose, in each case a screw reaches through the milling tooth holder into the threaded hole 22, as will be explained later in detail in relation to
The milling tooth tip 16 is separated from the milling tooth base 18 by a dividing plane 24. 26 designates a longitudinal axis of the milling tooth body. This is perpendicular to a base 28 of the milling tooth base 18. The milling tooth tip 16 is narrower than the milling tooth base 18 (cf.
In the embodiment illustrated, the second section 36 of the working side 30 of the milling tooth tip 26 is tilted by a predetermined first angle 42 of 12 degrees with respect to the longitudinal axis 26 of the milling tooth body. The third section 38 has a radius of curvature of 60 mm. The dividing plane 24 between milling tooth base 18 and milling tooth tip 16 is tilted with respect to the longitudinal axis 26 by a predetermined second angle 44 of 100 degrees. The first section 34 projects beyond the flange side 12 by a length 46 of 33.4 mm. The milling tooth tip 16 projects beyond the flange side 12 by a length 48 of 78 mm. The first section 34 has a height 50 of 29.5 mm. The milling tooth tip 16 has a width 52 of 23 mm. The milling tooth base 18 has a width 54 of 55 mm.
As a result of the configuration according to the invention of the milling tooth 10, shear forces in the milling tooth body in the region of the transition from milling tooth tip 16 to milling tooth base 18, that is to say in the region of the dividing plane 24, are avoided. Instead, the milling tooth 10 is supported with the first section 34 on the milling tooth holder. At the same time, an end face of the milling tooth base 18, pointing in the working direction 32, is also formed as part of the working surface 30 of the milling tooth body, so that mechanical loading of the milling tooth 10 acts on the entire surface 30 and thus on the entire milling tooth body and not just on the milling tooth tip 16. At the same time, the milling tooth holder is covered completely in the working direction 32 by the milling tooth 10, so that the milling tooth holder is protected against the direct mechanical action of force or loading.
In addition, on the flange side 12, in the region of the threaded hole 22, the milling tooth 10 has an oval recess 56, which additionally interacts in a stabilizing manner with a flange side of the milling tooth holder, as will be described in more detail below.
FIGS. 4 to 6 illustrate a preferred embodiment of a milling tooth holder matching the abovedescribed milling tooth 10. This has a flange side 58 with an oval elevation 60 corresponding to the oval recess 56 in the flange side 12 of the milling tooth 10. The milling tooth holder has two through holes 62 which are aligned with the threaded holes 22 in the milling tooth 10.
As can be seen in particular from
Number | Date | Country | Kind |
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201 16 344.6 | Oct 2001 | DE | national |
Filing Document | Filing Date | Country | Kind |
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PCT/EP02/11227 | 10/7/2002 | WO |