Patent ID: 12208460

DETAILED DESCRIPTION OF THE INVENTION

InFIGS.1to11, identical, similar or identically acting elements are designated by identical reference signs and a repeated description of these elements is dispensed with in the following description in order to avoid redundancies.

FIGS.1and2show a schematic illustration of a plate-shaped cutting tool1according to a first embodiment in plan view and in side view respectively. The cutting tool1is in the form of an oscillating saw blade which can be moved in an oscillating manner along the directions2at a frequency of, for example, 20,000 strokes per minute. During such an oscillation, a plate-shaped tool bit3, which consists of a steel, is brought into contact with a nonmetallic material, for example a wood or a bone material. In the process, cutting of the nonmetallic material is performed by means of triangular cutting teeth4of the tool bit3, the number of teeth that can be seen inFIG.1being chosen merely by way of example. Here, a corresponding cutting depth or feed can be set by an axial movement parallel to a longitudinal axis5of the cutting tool1in the direction of the cutting teeth4. The tool bit3is materially connected to a holding plate6by a weld seam7. The weld seam7, whose extent in the axial direction is substantially less than that of the holding plate6and the tool bit3, thus forms a boundary region, which may also be referred to as a connecting region, between the tool bit3and the holding plate6. As a result, the holding plate6can absorb the forces which occur during machining and which may also be referred to as cutting reaction forces. The holding plate6is monolithic and consists of a hard metal (cemented carbide) with a modulus of elasticity of 650·109N/m2; however, other materials are also conceivable and also possible within the scope of the present disclosure. The tool bit3is likewise monolithic, being made of a steel having a modulus of elasticity of 210·109N/m2. Hence, the region60of the holding plate6which adjoins the weld seam7is more resistant to bending than the region30of the tool bit3which adjoins the weld seam7. The effect is that the holding plate7counteracts a deflection of the cutting element4in one of the directions perpendicular to the longitudinal axis5, for example in the directions2or one of the directions which are oriented perpendicularly to the plane of the drawing inFIG.1, and parallel thereto, thus reducing the influence of cutting reaction forces, which can act on the tool bit3in the region of the cutting teeth4, on the position of the tool bit3with respect to a fixed reference point located outside the cutting tool1. The reference point can thus be assigned, for example, to a clamping device for clamping and holding the nonmetallic material. Since the tool bit3consists of a steel, the cutting teeth4can be produced by stamping with subsequent grinding.

FIG.1shows particularly clearly that the weld seam7extends over the entire width of the holding plate7and the tool bit3, is linear and is oriented perpendicularly to the longitudinal axis (some other orientation is also conceivable and also possible, in the case of a different tool bit3and/or a different holding plate6, for example, parallel to the longitudinal axis5or inclined with respect to the longitudinal axis5, that is to say extending obliquely in the latter case). Geometrically speaking, the weld seam7can therefore be considered as a connecting line between two points100and110of corresponding outer edges500of the cutting tool1.

The holding plate6is furthermore connected to a connecting plate8by another weld seam9. The connecting plate8is likewise monolithic, being made of a steel having a modulus of elasticity of 210·109N/m2. Since the connecting plate8is made of steel, a concave recess80in the connecting plate8can be obtained by stamping, wherein the recess80is shaped to correspond to a drive shaft (not illustrated) of an electric motor, allowing the cutting tool1to be driven by means of the electric motor in order to carry out the oscillating movements in the directions2. In this way, an electric power tool is made available.

FIG.2shows particularly clearly that the cutting tool1has a constant thickness, which may also be referred to as plate thickness, which consequently is the same in terms of magnitude in the region of the tool bit3, the holding plate6and the connecting plate8.

FIG.3shows a schematic illustration of a plate-shaped cutting tool1′ according to a second embodiment in plan view and in side view respectively. Cutting tool1′ is of similar construction to cutting tool1, wherein, in contrast to cutting tool1, a connecting plate8′, which consists of the steel of the connecting plate8, has a recess80awith radial projections800aand an axial plug-in slot810a, which are shaped to correspond to a drive shaft (not illustrated) of the electric motor, in order to transmit more positive-locking forces to the cutting tool1′ than recess80. Furthermore, connecting plate8′ is longer in the axial direction than the connecting plate8of cutting tool1, increasing the surface contact with a clamping device of an electric power tool drive unit. Furthermore, tool bit3′ is shorter in the axial direction than tool bit3, making tool bit4′ more flexurally rigid. By way of example, the number of cutting teeth4′ is greater than the number of cutting teeth4.

FIGS.4and5show a schematic illustration of a plate-shaped cutting tool1″ according to a third embodiment in plan view and in side view respectively. Cutting tool1″ is of similar construction to cutting tool1, wherein cutting element3″, which consists of the steel of cutting element3, is illustrated without cutting teeth, and a connecting plate8″, which consists of the steel of connecting plate8, has a recess80bwith a plug-in slot800b.

FIG.5shows particularly clearly that the cutting tool1″ has a constant thickness, which may also be referred to as plate thickness, in the region of the tool bit3″ and the holding plate6which is the same in magnitude in these regions, and has a constant thickness, i.e. plate thickness, in the region of connecting plate8″ which is greater than the plate thickness in the regions of the tool bit3″ and the holding plate6.

FIGS.6and7show a schematic illustration of a plate-shaped cutting tool1′″ according to a fourth embodiment in plan view and in side view respectively. Cutting tool1′″ is of similar construction to cutting tool1″, wherein, as can be seen particularly clearly fromFIG.7, a thickness, that is to say plate thickness, of cutting tool1′″ in the region of a holding plate6′″, beginning at the weld seam7with a thickness which corresponds to the thickness of tool bit3″, increases continuously until the thickness of the connecting plate8″ at the weld seam9is reached. In this case, holding plate6′″ consists of the hard metal (cemented carbide) of holding plate6.

FIGS.8and9show a schematic illustration of a plate-shaped cutting tool1″″ according to a fifth embodiment in plan view and in side view respectively. Cutting tool1″″ is of similar construction to cutting tool1′″, wherein, as can be seen particularly clearly fromFIG.8, a holding plate6″″ has a width which is dimensioned transversely to the longitudinal axis2and which becomes continuously smaller from weld seam9to weld seam7; at weld seam9, the width corresponds to a similarly dimensioned width of the connecting plate8″. Accordingly, the cutting tool1″″ has a taper, specifically in the region of the holding plate6″″. At weld seam7, the width of the holding plate6″″ corresponds to the distance between points100″″ and110″″ of corresponding outer edges of the cutting tool1″″. In this case, holding plate6″″ consists of the hard metal (cemented carbide) of holding plate6.

FIGS.10and11show a schematic illustration of a plate-shaped cutting tool1′″″ according to a sixth embodiment in plan view and in side view respectively. Cutting tool1′″″ is of similar construction to cutting tool1′, wherein, as can be seen particularly clearly fromFIG.11, a connecting plate8′″″, which consists of the steel of connecting plate8, two mutually adjacent surfaces1000and1100, which can be seen in profile in the side view according toFIG.11analogously to a corresponding longitudinal section, form an inner edge angle of 135°. Thus, cutting tool1′″″ is cranked in such a way in the region of the connecting plate8′″″ that a clearance1200(visible inFIG.11) is obtained transversely to the longitudinal axis5in the region of the connecting plate8′″″, as compared with cutting tool1for example, enabling the clearance1200to be used to provide additional assembly space for connection to an electric motor of a drive unit or the like, it being possible, while remaining within the clearance1200, for a tool bit3′″″ simultaneously to make contact with a base or the like parallel to its areal extent (visible inFIG.10). A transition from surface1000to surface1100or vice versa is indicated inFIG.10by a dashed line1300, which extends parallel to a transverse axis. Connecting plate8′″″ has a radially closed recess80cwith projections800cfor positive connection to a shaft of an electric motor.

Tool bit3′″″, which consists of the steel of tool bit3, is longer than tool bit3′ in order to obtain axial machining space for severing the nonmetallic material.