SAW TOOTH WITH HARD LAYER

Abstract

A saw tooth has a base body comprising a solderable hard metal and a hard layer comprising a material that is harder than the hard metal of the base body; the hard layer is provided on a front face of the base body, and the tooth face has at least one chamfered and/or rounded face portion.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1 and 2 each show a section through a saw tooth according to the invention; and

FIG. 3 is a detail of a machining tool of the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIG. 1 shows a saw tooth 1 of the invention in a horizontal section. A base body 2 of the saw tooth 1 has a square cross section. A hard layer 3 is applied to a front face 20 of the base body 2, over the full surface. An outer surface, facing away from the base body 2, of the hard layer 3 is a completely rounded face portion, which forms a tooth face 10 of the saw tooth 1. The tooth height, that is, the length measured at the tooth face 10, is as a rule from 1 to 10 mm. Because of the concave, hollow embodiment of the tooth face 10 as shown, at the two edges of the tooth face 10 a cutting edge 11, shown in section as a pointed tip, and a further cutting edge 12, also shown as a pointed tip, are embodied.

The cutting edges 11, 12 formed of the material of the hard layer 3, on entering into a material that is to be cut, lead to a precise cut. An embodiment of two cutting edges 11, 12, by means of a uniform contact, which in particular distributes forces equally, of the cutting edges 11, 12 on the face to be cut of a material such as wood that is to be cut and thus additionally improves the cutting quality of the saw tooth 1 of the invention. With the aid of the cutting edges 11, 12, the saw tooth 1 of the invention can sever a material which at maximum has the hardness of the material of the hard layer, advantageously diamond. The shape of the tooth face 10 is embodied entirely by the hard layer 3, which rests on the flat front face 20 of the base body 2. The tooth face 10 is shaped for instance in an erosion production process from the hard layer 3, which in the prefabricated state may have a thickness which is greater than or equal to the height shown here of the cutting edges 11, 12.

In FIG. 2, a further embodiment of the saw tooth 1 of the invention is shown. The front face 20 of the base body 2 is uneven and is put together from two symmetrically located chamfered face portions. The contour of the front face 20 is V-shaped, embodied mirror-symmetrically to the middle. In the embodiment shown, the hard layer 3 provided on the front face 20 of the base body 2 has a uniform thickness. The contour of the tooth face 10 follows the contour of the front face 20, so that the tooth face 10 likewise has two chamfered face portions located symmetrically in the shape of a V and consequently has two peripheral cutting edges 11, 12.

The advantage of this kind of embodiment is that to produce the saw tooth 1 of the invention, and in particular to attach or apply the hard layer 3, a smaller quantity of hard layer material can be used. It is furthermore conceivable in this embodiment for the hard layer 3 to have different thicknesses, specifically in such a way that in the region of the cutting edges 11, 12, the hard layer 3 has a greater thickness than in the middle region of the tooth face, which contributes little to the cutting performance of the saw tooth 1.

In FIG. 3, an attachment of the saw tooth 1 to a machining tool 4 is shown. This figure shows a sector of the wood machining tool 4 embodied as a circular saw blade. A saw blade blank 40 has a comb like row of teeth on its peripheral surface, and a second saw tooth 42, a third saw tooth 43, a fourth saw tooth 44, and a fifth saw tooth 45 are correspondingly mounted on the successively located combs of the saw tooth 1. The saw teeth 1, 2, 43, 44 and 45 of the invention are fastened by their respective base bodies of solderable hard metal to the saw blade blank 40.

The base bodies of the saw teeth 1, 2, 43, 44 and 45 have corresponding attachment means for making a form lock with the saw blade blank 40. The tooth faces of the saw teeth 1, 2, 43, 44 and 45 of the invention, like the tooth face 10 of the saw tooth 1, are oriented in the tangential direction. The cutting edges embodied in pointed form according to the invention on the saw teeth 1, 2, 43, 44 and 45 assure high dimensional accuracy and rectilinearity of a cut made with the machining tool 4. Additional sharpening and/or grinding of the saw teeth 1, 2, 43, 44 and 45, in the embodiment of the machining tool of the invention, is unnecessary, or is needed only at very long time intervals, which increases the service life of the machining tool 4.

Further embodiments of the saw tooth 1 of the invention with one or more, preferably parallel cutting edges and with one or more chamfers provided on the tooth face 10 and/or on a tooth spine of the saw tooth 1, are conceivable. It is furthermore conceivable for only individual portions of the front face 20 to be covered with the hard layer 3. Those portions may be limited to the regions of the cutting edges where the material of the hard layer 3 has the function of a highly wear-resistant cutting material.

To improve the cutting quality and the service life, a saw tooth 1 of the invention has a base body 2 of a solderable hard metal and a hard layer 3 of a material which is harder than the hard metal of the base body 2. Chamfered and/or rounded face portions provided on the tooth face 10 create cutting edges 11 and 12, which because of the hard layer 3 provided on the tooth face 10 are reinforced and more wear-resistant and which assure a durably high-quality cutting performance of the saw tooth 1 of the invention. A cutting performance that has smooth cut faces is imparted to a machining tool 4 by a saw tooth or saw teeth 1, 2, 43, 44 and 45 according to the invention made on it and thus this machining tool assures a high cutting quality.

It will be understood that each of the elements described above, or two or more together, may also find a useful application in other types of constructions differing from the type described above.

While the invention has been illustrated and described as embodied in a saw tooth with hard layer, it is not intended to be limited to the details shown, since various modifications and structural changes may be made without departing in any way from the spirit of the present invention.

Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can, by applying current knowledge, readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential characteristics of the generic or specific aspects of this invention.

Claims

1. A saw tooth, comprising a base body having a front face and a solderable hard metal; and a hard layer comprising a material that is harder than the hard metal of said base body, said hard layer being provided on said front face of said base body and having a tooth face with at least one portion selected from the group consisting of a chamfered face portion, a rounded face portion, and both.

2. A saw tooth as defined in claim 1, wherein said tooth face of said hard layer is hollow.

3. A saw tooth as defined in claim 2, wherein said tooth face has a shape selected from the group consisting of a concave shape and a V shape.

4. A saw tooth as defined in claim 1, wherein said front face of said base body is flat, and said hard layer has different thicknesses.

5. A saw tooth as defined in claim 1, wherein said front face of said base body has a contour of said tooth face with said hard layer.

6. A saw tooth as defined in claim 1, wherein a chamfer is provided on an element selected from the group consisting of a tooth spine of the saw tooth, the tooth face, and both.

7. A saw tooth as defined in claim 1, wherein the material of said hard layer contains diamond.

8. A saw tooth as defined in claim 7, wherein the material of said hard layer contains the diamond in polycrystalline form.

9. A machine-driven machining tool, comprising a machining tool selected from the group consisting of a band saw blade, a milling cutter, and a drill having at least one saw tooth, said saw tooth having a base body having a front face and a solderable hard metal, and a hard layer comprising a material that is harder than the hard metal of said base body, said hard layer being provided on said front face of said base body and having a tooth face with at least one portion selected from the group consisting of a chamfered face portion, a rounded face portion, and both.

10. A machine-driven machining tool as defined in claim 9, wherein the machine-driven machining tool is configured as a circular saw blade.