Cutting tool for recessing and grooving

Abstract

A cutting tool for radial and axial recessing and for lateral motion for so-called grooving of primarily metallic materials, having a clamping holder and a cutting element base, fastened to the clamping holder, on which a cutting element rests, the cutting element being pressed onto the cutting element base by a clamping finger of a clamping claw, and the cutting element being guided on the cutting element base with a prism.

Claims

1. A cutting element having a top side and bottom side, and having side surfaces which connect the top side and bottom side, and having two oppositely inclined flat rectangular roof slopes on said top side which extend, starting at the surface, into the cutting element; wherein a rectangular ridge surface which forms part of the surface of the cutting element is situated between the two roof slopes; on top of the cutting element on both ends, the one facing away from the clamping holder and the one facing towards the clamping holder are surfaces that are part of the top side surface and between the surfaces the roof slopes are situated wherein the roof slopes extend at an angle of 15>a>5 with respect to the surface of the cutting element, the roof slopes extending, starting at the ridge surface, to the edge of the cutting element and wherein the cutting element has protruding engagement elements on its bottom side.

Description

(1) Further features of the invention are shown in the twelve figures described below:

(2) FIG. 1: shows a cutting tool 1 according to the invention, having a clamping holder 2, cutting element base 3, clamping claw 5, and cutting element 6;

(3) FIG. 2: shows the elements according to FIG. 1 in enlarged scale;

(4) FIG. 3: shows the clamping holder 2 with the fastened cutting element base 3 and with the cutting element 6 placed thereon;

(5) FIG. 4: shows only the clamping holder 2;

(6) FIG. 5: shows only the clamping holder 2 with the fastened cutting element base 3;

(7) FIG. 6: shows a clamping claw 5 according to the invention with the inserted clamping screw 17 in a [perspective] view;

(8) FIG. 7: shows the clamping claw 5 without the inserted clamping screw;

(9) FIG. 8: shows the clamping claw 5 from below;

(10) FIG. 9: shows the clamping holder 2 according to FIG. 4 from the side;

(11) FIG. 10: shows the clamping holder 2 from the top;

(12) FIG. 11a shows the cutting element base 3 from the side.

(13) FIG. 11b shows the cutting element base in cross section;

(14) FIG. 12a shows the cutting element 6 according to the invention from the top; and

(15) FIG. 12b shows the cutting element in a perspective view.

(16) The clamping holder 2 described here is also referred to as a base holder, the cutting element base 3 is also referred to as a parting blade, and the clamping claw 5 is also referred to as a parting insert.

(17) The invention relates to a cutting tool 1 (see the figures) which in its basic design may be used alike for recessing, thread cutting, and grooving. The cutting tool is always composed of a base support, referred to below as a clamping holder 2, an exchangeable cutting element base 3, and an exchangeable cutting element hold-down device, referred to below as a clamping claw 5. The cutting element base 3 and the clamping claw 5 form the so-called clamping system, and are adapted to the shape and function of the cutting element 6 used.

(18) The clamping holder 2 (see FIGS. 1 through 5) has a guide groove 10 in the axial direction (see FIG. 4), in the base of which a threaded hole 11 is introduced. A tongue 24 protrudes into this guide groove 10 at the side of the cutting element base 3 facing the clamping holder 2. The tongue 24 is inserted into the guide groove 10 with a precise fit, so that the cutting element base 3 is precisely guided on the clamping holder 2.

(19) For the positive-fit connection of the cutting element 6 on the cutting element base 3, the cutting element 6 is guided by a prism-shaped connection, also referred to as a guide strip 14, between the bottom side of the cutting element 6 and the top side of the cutting element base 3. Possible shape and position errors of the cooperating components are compensated for by the same axial orientation of the components and the mutually coordinated tolerances of the units, guides, and prisms in the technical sense of a clearance fit.

(20) Furthermore, the cutting element 6 is also guided on its top side 15a. For this purpose, the cutting element 6 has two oppositely inclined, flat rectangular roof slopes 7 in the manner of a saddle roof or gable roof of a house which extend, starting at the surface 12, into the cutting element 6. These roof slopes 7 allow twist-free insertion into a cutting tool 1.

(21) A ridge surface 9 which forms part of the surface 12 of the cutting element is situated between the two roof slopes 7. The four sides of the ridge surface 9 form a rectangle. The shorter side is preferably equal to the distance b between the ridge surfaces 9, and the longer side of the rectangle is preferably equal to the width B of the roof slopes (see FIG. 11a).

(22) In the embodiment shown here, the roof slopes 7 extend at an angle =10 (see FIG. 12b) with respect to the surface 12 of the cutting element 6, the roof slopes 7 extending, starting at the ridge surface 9, to the edge of the cutting element 6.

(23) For anchoring the cutting element 6 to the cutting element base 3 with a precise fit, the cutting element 6 has protruding engagement elements 23 on its bottom side. The cutting element 6 is thus guided in a twist-free manner on its bottom side 15b, and on its top side 15a via the roof slopes 7. The engagement elements 23 are preferably spherical projections. The engagement elements 23 are part of a prism guide.

(24) Another feature is the special design and bearing of the clamping claw 5, which is fastened to the top side of the clamping holder 2 by a clamping screw 17. The clamping claw 5 rests with its inclined plane 21 on an inclined plane 16 on the clamping holder 2, and is guided with a precise fit by the guide surface 18 (see FIGS. 3 through 8). The clamping force of the clamping screw 17 presses the clamping claw 5 onto the clamping holder 2 on the inclined plane 16 until the bearing points 19 of the clamping claw arrive at the inclined plane 16. Further tightening of the clamping screw 17 acts as a lever effect and clamps the clamping finger 4 of the clamping claw 5 in the direction of the cutting element 6, thus exerting an additional clamping force on the cutting element 6. As a result of this clamping force the cutting element 6 is pressed into the prism, and the guide strip 14 is pressed onto the cutting element base 3.

(25) To reinforce this lever effect, the bearing points 19 and the leadthrough 13 for the clamping screw 17 are situated at the maximum possible distance from one another on the inclined plane 21.

(26) The cutting element 6 is preferably made of a ceramic and/or PCBN or a CBN material.

(27) The cutting element 6 may also be provided with a coating for increasing the hardness.