WO2005107987A1

WO2005107987A1 - Knife plate and reamer

Info

Publication number: WO2005107987A1
Application number: PCT/EP2005/004773
Authority: WO
Inventors: Dieter Kress; Friedrich Haeberle
Original assignee: MAPAL Fabrik für Präzisionswerkzeuge Dr. Kress KG
Priority date: 2004-05-04
Filing date: 2005-05-03
Publication date: 2005-11-17
Also published as: DE102004022940A1; WO2005107987A8; EP1744846A1

Abstract

Disclosed is a knife plate comprising an elongate rectangular basic shape, a rectangular front face (3), an imaginary bisector (9) that separates the front face (3) into two halves, at least one cutting edge (31, 35), and a clamping groove (15) which is provided with at least one clamping area (17, 19). Said knife plate (1) is characterized in that the central axis (21) of the clamping groove (15) is inclined in relation to the bisector (9) by an angle alpha of 10° while the clamping area (17, 19) and the front face (3) enclose an angle gamma of 20° to 30°, preferably 23° to 27°, especially about 25°, the center point (23) of the central axis (21) of the clamping groove (15) coincides with the center point of the bisector (9) of the knife plate (1), and the clamping groove (15) is embodied so as to be point-symmetric to the center point (23) of the bisector (9). Also disclosed is a reamer comprising an adjusting device (45) by means of which the projecting length of a cutting edge (35, 31) of a knife plate (1) beyond the guiding strips (75, 77) of the reamer (10) can be adjusted. The blockable adjusting device (45) of the reamer is provided with only one adjusting screw (55) which acts upon a first end of the knife plate (1) either directly or via an adjusting wedge (57) while the second end of the knife plate (1) leans directly on the bottom (65) of the groove (64).

Description

Knife plate and reamer

description

The invention relates to a knife insert according to the preamble of claim 1 and a reamer according to the preamble of claim 10.

Knife plates and reamers of the type mentioned here are known. The cutting inserts are inserted into the main body of the reamer, which is provided with a groove. A clamping device is provided to fix the knife plate in the groove. The radial protrusion of the insert over the guide strips in the base of the reamer is set by an adjustment device. Knife inserts of the type mentioned here have a main cutting edge inclined in the direction of advance of the tool and a secondary cutting edge falling in the opposite direction. The inclination of the minor cutting edge is adjusted together with the radial protrusion by means of the adjusting device in such a way that there is a taper of approximately 1 μm per 1 mm. Conventional reamers have adjustment devices with an adjusting screw. If necessary, an adjusting wedge cooperating with this is provided, which has a larger contact surface on the knife plate than the set screw. When adjusting the radial protrusion and thus the taper, the cutter insert is inserted by hand into the groove in the base body of the reamer and pressed there in the radial and axial direction. Then the clamping device is tightened in order to fix the knife plate in the groove. Only now is the adjusting device used to set the desired radial projection and thus the outside diameter of the reamer. To perform this task, a knife plate in the clamped state A reamer with a knife plate, which is provided with a clamping groove, the flanks of which fall at an angle to the front of the knife plate, is known in order to be able to optimally adjust against a pretension created by the clamping device. All known systems of this type provide this procedure when changing the knife inserts. A knife plate is installed and removed on the one hand when the reamer is first loaded, and on the other hand when the cutting edge of the knife plate is worn. It is relatively time consuming to set the desired radial projection. It also requires measuring devices to measure the diameter and some practice for this.

The object of the invention is therefore to provide a knife insert and a reamer, with the aid of which the disadvantages mentioned here are avoided.

To achieve this object, a knife insert is proposed which has the features mentioned in claim 1. It is an elongated rectangular knife insert with a corresponding rectangular front, which is provided with a clamping groove. A clamping claw of a tensioning device can engage in this. In order to be able to clamp the insert with a sufficient force in the groove of a reamer that receives it, the central axis of the clamping groove is inclined by an angle α of 10 ° with respect to the central axis of the insert, the center of the central axis of the clamping groove and the center of the center line Knife plate collapse and the clamping groove is point symmetrical to the center of the center line. The clamping groove is designed and aligned in such a way that the knife plate can be pressed against an adjusting device of a reamer with such a force is that the adjustment device is pushed into a defined position and any play between the built-in parts is eliminated. To accomplish this task, the flanks of the clamping groove drop off at an angle in the range from 20 ° to 30 °, preferably 25 °, in relation to the front of the cutter insert. In contrast to known reamers, in which an additional clamping force has built up due to the adjustment process and the clamping groove, the clamping force must now be applied solely via the clamping device. The clamping force must be so great that any play in the adjustment elements is pressed together. Such a design of the cutter insert enables it to be inserted and tightened in the groove of a reamer after the adjustment device has been set without having to readjust the adjustment device.

Further configurations of the knife plate result from the subclaims.

To solve this problem, a reamer is also proposed which has the features mentioned in claim 10. It comprises a base body provided with at least one groove, into which a knife insert with a geometrically defined cutting edge can be inserted. A tensioning device is provided for fastening them. An adjustment device is used to adjust the radial projection of the cutter insert over the guide strips in the base body. This comprises only one set screw, which acts directly or via an adjusting wedge on a first end of the knife plate. The special feature of the adjustment device is that it can be blocked. So after the first setting of a knife plate, which is in the groove of the basic body of the reamer is inserted, rendered inoperative and sealed, for example.

Further refinements of the reamer result from the subclaims.

The invention is explained in more detail below with reference to the drawing. Show it:

Figure 1 shows a knife plate in plan view;

Figure 2 shows a cross section through the knife plate according to Figure 1 along the line II-II;

Figure 3 is a schematic diagram of a knife plate with a clamping device and an adjusting device and

FIG. 4 shows a perspective sketch of a reamer with a knife insert according to FIGS. 1 and 2.

The knife plate 1 shown in FIG. 1 has a preferably elongated, rectangular basic shape as seen in plan view and shows a rectangular front side 3. A rake face 7 runs along a first longitudinal edge 5. The knife plate is preferably essentially symmetrical and has a center line 9 on. A second longitudinal edge 11 runs parallel to the first longitudinal edge 5 and a second rake face 13 runs along it. The first and second rake faces 7, 13 are each delimited by a chip breaker step 14, 14 '. While the rake faces 7, 13 drop off from the associated longitudinal edges 5, 11 in the direction of the back of the knife plate 1, the chip guide steps 14 rise, 14 'towards the front 3. In the central area of the front side 3 between the rake faces 7 and 13 there is a clamping groove 15 with at least one, here two clamping surfaces 17 and 19, which is at an angle y between 15 ° and 35 °, preferably from about 20 ° to the front 3 30 °, preferably drop from 25 °. The clamping groove 15 is formed symmetrically to a central axis 21, which includes an angle α of approximately 10 ° with the center line 9 of the cutting tip 1.

The clamping groove 15 is arranged point-symmetrically to the intersection 23 of the center line 9 and the center axis 21.

The length of the clamping groove 15 measured along the central axis 21 is preferably selected such that it is arranged exclusively in the central region of the front side 3 and does not intersect the rake faces 7 and 13. Rather, the clamping groove is closed all around and has a step on its narrow sides 25 and 27 with respect to the front side 3. This embodiment offers the advantage that under a clamping claw 15 which engages in the clamping groove 15, which is not shown here, no chips can penetrate, and thus an optimal hold of the cutter plate 1 on the base body of a reamer is ensured.

On the upper left corner of the knife plate 1 shown in FIG. 1, a bevel is provided, that is to say the longitudinal edge 5 does not reach the upper end face 29 of the knife plate 1, but falls off at an angle to the center line 5 beforehand. This area, which slopes towards the end face 29, forms the geometrically determined main cutting edge 31 of the cutting tip, which via an apex 33 leads into a geometrically determined secondary cutting edge 35 passes over, which is formed by the region of the longitudinal edge 5 adjoining the apex 33. When using the knife insert 1, it is inserted into a tool in such a way that the secondary cutting edge 35 falls in the direction of the axis of rotation of the tool, usually by approximately 1 μm to 1 mm.

The cutter insert 1 is also of point symmetry with respect to the intersection 23. A main cutting edge 31 ′ is also provided on the diagonally opposite corner of the knife plate, which drops from the second longitudinal edge 11 in the direction of the end face 37. The main cutting edge 31 'merges via an apex 33' into a secondary cutting edge 35 'which is inclined in the opposite direction to the main cutting edge 31' and drops to the end face 29. The point-symmetrical design of a knife insert 1 with two cutting edge areas lying diagonally opposite one another is basically known. Such a knife insert 1 is referred to as an insert. When the main cutting edge 31 and secondary cutting edge 35 are worn, the cutting tip 1 can be rotated through 180 ° about an imaginary axis perpendicular to the front side 3 through the intersection 23, so that the main cutting edge 31 'and the secondary cutting edge 35' for the machining of a workpiece are available.

The end faces 29 and 37 are usually arranged at an angle of 90 ° with respect to the front side 3, that is to say they drop perpendicularly into the image plane of FIG. 1 in the illustration according to FIG. In contrast, the side surfaces 39 and 41 adjoining the longitudinal edges 5 and 11 are inclined at an angle of <90 °, they fall towards the center line 9. If one looks at the cutter plate 1 from the end face 29, it is essentially trapezoidal 1, the front side 3 visible in FIG. 1 is wider transversely to the center line 9 than the rear side of the knife plate 1 lying opposite and parallel to the front side 3. The angle at which the side surfaces 39 and 41 extend from the longitudinal edge 5 and 11, respectively seen falls, is called clearance angle.

In the exemplary embodiment according to FIG. 1, it is provided that the chip breakers 14, 14 ′ run parallel to the associated longitudinal edges 5, 11 of the knife plate 1. The rake faces 7 and 13 thus have an essentially constant width, as seen over the length of the cutting tip 1. However, it is also conceivable that the chip breakers 14, 14 ^{* run} at an angle with respect to the associated longitudinal edges 5, 11, in such a way that the chip faces 7 and 13 widen in the direction of the main cutting edge 31, 31 '. The embodiment variant mentioned here is indicated in FIG. 1 by dashed lines.

With this configuration, the chip guide stages 14, 14 'in the direction of the main cutting edge 31, 31' are higher, so that greater efficiency is achieved when breaking away chips. In addition, due to the broadening rake faces 7, 13 chips of greater thickness can be removed from a workpiece, which results in a greater depth of cut.

Depending on the length of the insert 1, the angle at which the chip breakers 14, 14 'run relative to the associated longitudinal edges 15, 11 can be varied. With short knife inserts it is possible that this corresponds to the angle α at which the Telachse 21 of the clamping groove 15 runs relative to the center line 9 of the cutting tip 1.

In the exemplary embodiment of the knife insert 1 according to FIG. 1, it is assumed that the main cutting edges 31, 31 'are machined out of the base body of the knife insert 1. However, it is also conceivable to use an insert made of PCD or CBN in the area of the main cutting edge 31, 31 'and the secondary cutting edge 35, 35'. In this case, the rake faces 7 and 13 and the chip breakers 14, 14 'run only over the length of this insert.

Figure 2 shows a cross section through the knife plate 1 shown in Figure 1, along the line II-II drawn in this figure. The same parts are provided with the same reference numerals, so that reference is made to the description of the previous figure.

The sectional view clearly shows that the knife plate 1 has a base body into which the clamping groove 15 is made. This has the two clamping surfaces 17 and 19, which run in a V-shape with respect to one another and form an angle y with the front side 3. This angle y is in the range from 20 ° to 30 °, preferably from 23 ° to 27 ° and is in particular approximately 25 °. On the clamping surfaces 17 and 19, which are also referred to as flanks of the clamping groove 15, the clamping lip of a clamping claw rests, with which the cutting tip 1 is fixed in the base body of a reamer. This will be discussed in more detail below.

Starting from the longitudinal edges 5 and 11 of the knife plate 1, rake faces 7 and 13 extend in the direction of the center line of the knife plate 1, which are at an acute angle to the front side 3 run, that is, seen from the longitudinal edges 5 and 11 drop inwards. The rake faces 7 and 13 end in chip breaker stages 14, 14 ', against which chips removed from the cutter plate 1 run up and are broken.

Figure 3 shows a schematic diagram of the knife plate shown in Figures 1 and 2 with a clamping device 43 and an adjusting device 45. The knife plate 1 is shown in a highly simplified manner.

The clamping device 43 has a clamping claw 47 which engages with a clamping lip 49 in the clamping groove 15, which is provided on the front side 3 of the cutting tip 1 and was explained in detail with reference to FIG. 1.

The tensioning device 43 has a tensioning screw 51, which preferably has two threaded sections which are distinguished by opposing pitches. A first threaded section engages in an internal thread, which is provided in a through hole 53, which passes through the clamping claw 47 and serves to receive the clamping screw 51. The other threaded section of the clamping screw 51 engages in the base body of a reamer, not shown here.

If the clamping screw 1 is set in rotation by means of a suitable tool, the clamping claw 43 is tightened in a first direction of rotation, so that the clamping lip 49 interacts with a clamping surface of the clamping groove 15. The oblique arrangement of the clamping groove 15, which was explained in detail with reference to FIGS. 1 and 2, splits the clamping forces applied in this way into two force components: a first partial force acts perpendicular to Center line 9 of the insert 1, a second partial force in the direction of the center line 9, here to the left.

The adjusting device 45 has an adjusting screw 55 which cooperates with its external thread with the internal thread of a bore made in the base body of a reamer. When the adjusting screw 55 is rotated, it is screwed more or less far into the base body of the reamer, whereby it either acts directly on the side surface 39 of the cutter plate 1, which is also referred to as the free surface, or, as shown here, via an adjusting wedge 57 which has an inclined surface 59 has, which is inclined so that it rests flat against the side surface 39 of the cutting tip 1 and its longitudinal edge 5, so that the secondary cutting edge 35 provided here does not damage.

It can be clearly seen that the adjusting device 45 has only a single adjusting screw 55, here with an adjusting wedge 57.

Because the clamping device 43 and the adjusting device 45 lie directly next to one another and the adjusting device comprises only one set screw, the knife plate 1 can be made very short in the direction of its center line 9. This prevents the knife plate from possibly bending, which can lead to the knife plate breaking if two adjusting screws are used.

The short design of the knife insert 1 is further promoted by the fact that the clamping claw 47 of the clamping device 43 is arranged at an angle β of approximately 10 ° with respect to an imaginary vertical line 61, which for example intersects the through bore 53, and in the direction of the adjusting device 45 is inclined. The short design of the knife plate results in a very compact overall system. In addition, the knife plate is not bent and the taper originally set, i.e. the fall of the secondary cutting edge, remains constant.

In the illustration according to FIG. 3, it is assumed that the right front upper corner of the knife insert 1 has a main cutting edge 31 and a secondary cutting edge 35, as was explained in detail above with reference to FIG. 1.

FIG. 4 shows a perspective schematic diagram of a reamer 10 with a base body 61 and a cutter insert 1 inserted therein, as was explained with reference to FIGS. 1 to 3. The clamping device 43 and the adjusting device 45 can also be seen in the principle sketch selected here. The same parts are provided with the same reference numerals, so that reference is made to the previous description.

The cutter insert 1 is arranged in a groove 64 which is introduced into the base body 61 and runs essentially parallel to the axis of rotation 63 of the reamer 10 and has a base 65 and a side surface 67 against which the cutter insert 1 is pressed by the clamping device 43. The base body 61 of the reamer 10 is removed in the region of the front side 3 of the insert 1, so that a chip space 69 is formed, into which chips removed from the insert 1 pass.

4, it is also assumed that the right front corner of the knife insert 1 has a main cutting edge 31 and a secondary cutting edge 35, as was explained in detail above with reference to FIG. 1. In the presentation according to FIG. 4, the main cutting edge 31 drops in the direction of the feed direction indicated by a double arrow 71. Correspondingly, the minor cutting edge 35 falls counter to the feed direction to the axis of rotation 63 of the reamer 10 by appropriate arrangement and adjustment of the cutting tip 1 in the groove 64.

In the peripheral surface 73 of the reamer 10, two guide strips 75 and 77 are used, for example, which serve to guide the reamer 10 in a bore to be machined.

A dashed line in FIG. 4 also shows a coolant / lubricant channel 79, which opens into the chip space 69 via an opening 81, so that a coolant / lubricant can be applied in the vicinity of the main and secondary cutting edges 31, 35.

Due to the alignment of the clamping claw 47 with respect to the adjusting device 45 explained with reference to FIG. 3, the muzzle 81 can be brought very close to the cutting edges.

It is clear in FIG. 4 that the adjusting device 45 is closer to the front side 83 of the reamer 10 than the clamping device 43.

Regarding the function of the clamping device 43 and the adjusting device 45, the following should also be noted:

The adjusting device 45 serves to adjust the knife plate 1 such that its right front corner, i.e. its main cutting edge 31 and its secondary cutting edge 35, is displaced more or less in the radial direction with respect to the axis of rotation 63 via the guide strips 75, 77 to ultimately adjust the machining diameter of the reamer 10. Since only a single set screw 55 is provided, which can be displaced in a bore 85 in the base body 61, the radial adjustment of the knife plate 1 can be carried out very easily.

The groove 64 used to hold the cutter insert 1 has a very precisely inserted base 65, which lies at a precisely defined distance from the peripheral surface 43. The base 65 can thus serve in the region of the groove 64 facing away from the end face 83 as an abutment for the knife insert 1. This is therefore only in the region of its end facing the end face 83 on the adjusting screw 55 or the adjusting wedge 57, while its opposite second end, which faces away from the end face 83 of the reamer 10, rests directly on the base 65.

Due to the exact manufacture of the base 65, in particular with the aid of non-cutting machining methods such as laser ablation or sink erosion, the second end of the insert 1 is already exactly aligned in a radial orientation with respect to the axis of rotation 63 when the insert 1 is inserted into the groove 64. It is only necessary to adjust the front end of the cutter plate 1 facing the end face 83 by actuating the adjusting screw 55.

It can be clearly seen that the tool shown in FIG. 4 can be constructed very compactly and can have a short cutter plate 1, since the bottom 65 of the groove 64 provides a defined contact point in the region of the second end of the cutter plate 1, which is particularly the case with tools with a small size Diameter is of great advantage. However, as explained above, very precise processing is required. processing of the bottom 65 of the groove 64 in order to enable exact positioning of the cutting tip 1 in the reamer 10.

The clamping groove 15, which is arranged at an angle α and is inclined with respect to an imaginary horizontal 87, divides the clamping force exerted by the clamping claw 47 into two partial forces, one of which acts radially inwards in the direction of the axis of rotation 63 and one to the left against a stop located at the end of the groove 64 facing away from the end face 83, which is not visible in the illustration according to FIG. 4. The knife plate 1, which is preferably designed as a reversible plate, is thus pressed in a defined manner to the left against the stop, the force acting to the left in the direction of the axis of rotation 63 being substantially smaller than the force acting radially inwards. The measuring plate 1 is thus clamped exactly in the base body 61 of the reamer 10, a desired diameter dimension being adjustable with the aid of the adjusting device 45.

It is essential for the reamer described here that the adjusting device 45 only serves to set a defined initial dimension of the reamer 10, which is predetermined when machining a bore surface by means of the cutter insert 1 described here.

By means of the adjusting device 45, the desired diameter dimension is thus set after inserting a knife insert 1 into the reamer 10. Then the adjustment device is blocked, for example sealed.

If the knife plate 1 is worn out by machining bore surfaces, it no longer shows the desired sharpness or If the predetermined inner diameter of the bore can no longer be realized with the reamer 10, the clamping device 43 is released, so that the cutting tip 1 can be turned or exchanged. The turned or exchanged knife plate 1 is inserted into the groove 64 and brought into a defined starting position by hand: on the one hand it is pressed against the bottom of the groove 65 and on the other hand against a defined axial stop. Then the clamping device 43 is activated, that is, the clamping screw 51 is tightened such that the clamping claw 47 engages in the clamping groove 15 and builds up clamping forces via one of the clamping surfaces 17, 19. The inclined arrangement of the clamping groove 15, on the one hand, builds up forces which press the cutter insert 1 against the stop acting in the axial direction. On the other hand, clamping forces are built up which press the insert 1 against the set screw 55 or the adjusting wedge 57. Here is the following:

When a knife plate 1 was first installed in the reamer 10, the adjusting device 45 was set such that a defined protrusion of the knife plate 1 over the circumferential surface of the base body 61 or the guide strips 75, 77 of the reamer 10 built into it resulted, so that a defined one Rejuvenation of the minor cutting edge. When the knife plate is removed, the adjusting device 45 can relax. That is, after a knife plate 1 has been reinserted into the base body 61 of the reamer 10, the originally set diameter of the reamer 10, that is to say the desired projection of the knife plate 1, is not given. Due to the relaxation of the adjusting device 45, the knife plate 1 is initially too far over the bottom 65 of the groove 64 and thus over the circumferential surface or the guide strips of the base body 61.

Due to the special arrangement of the clamping groove 15, such large clamping forces are built up by means of the clamping device 43, in this case with the aid of the clamping claw 47, that the adjusting device 45 is elastically compressed again over a predetermined distance or the existing play between the built-in parts is eliminated. It can thus be achieved that the reamer 10 has a defined, desired diameter dimension after the reassembly of a cutter insert 1.

The particular advantage of the reamer 10 is therefore that after a desired diameter dimension of the reamer 10, that is to say a desired projection of the cutter plate 1 over the circumferential surface of the base body 61 or of the guide strips 75, 77, further adjustment work can be omitted. It is therefore possible to block the adjustment device, ie to deactivate it.

If a cutting edge of a knife plate designed as an indexable insert is worn, it can be removed from the groove 64, turned and reinstalled. After tightening the clamping screw 51, forces are exerted on the knife plate 1 by means of the clamping claw 47 such that the relaxation path of the blocked adjusting device 45 is reduced by an exactly definable amount and thus a defined diameter dimension of the reamer 10 is achieved. It is therefore possible, as explained above, to rotate the knife plate 1, which is preferably designed as an indexable insert, by 180 ° and the main and Arrange secondary cutting edges 31 'and 35' so that they are positioned as shown in FIG. 3.

In the reamer described here, all adjustment work is therefore omitted when turning a cutter insert or when replacing it. It is only necessary to activate the clamping device 43 and to fix the cutter insert 1 in the base body 61 of the reamer 10. The desired diameter of the reamer is set almost automatically.

The base 65 of the groove is inclined at an angle> 90 ° with respect to the side surface 67, that is, it falls off from the side surface 67 to the axis of rotation 63, the angle of inclination of the base 65 being adapted to the clearance angle of the cutter plate 1 so that it also coincides with the free surface, that is to say with its side surface 39, lies against the groove base 65.

Exposure is preferably provided in the transition region between the side surface 67 and the base 65 in order to ensure a precisely defined position of the knife plate 1. Such exposure is also provided in the transition area between the base 65 and a side surface of the groove 64 opposite the side surface 67 in order to rule out damage to the cutter plate 1, in particular the cutting edges.

Through the exact adaptation of the cross-sectional profile of the groove 64, that is to say the inclination of the base 65 with respect to the side surface 67, it is achieved that in the area of the end face 63 of the reamer 10, when the cutter insert 1 is installed, there is only an extremely small gap through which at most, only small amounts of impurities, in particular chips, can penetrate. On in this way, misalignment of the knife plate 1 and malfunction of the adjusting device 45 are reliably avoided.

FIG. 4 clearly shows once again that the reamer 10 can be designed to be very compact and space-saving because, firstly, only an adjusting screw 55 which can be arranged near the end face 83 is required and secondly because the clamping claw 47 is arranged inclined towards the end face 83, so that the clamping device 43 and the adjusting device 45 require only a very small amount of space. In addition, it is possible to design the knife plate 1 very small and compact. Finally, the compact design ensures that the mouth 81 of the coolant / lubricant channel 79 can be arranged very close to the main and secondary cutting edges 31, 35.

Claims

Expectations

1. Knife plate with

- at least one geometrically defined cutting edge (31, 35), an elongated rectangular basic shape, - a rectangular front (3),

- an imaginary center line (9) dividing the front (3) into two halves, an at least one clamping surface (17, 19) having a clamping groove (15),

characterized in that

- The central axis (21) of the clamping groove (15) ^' is inclined by an angle α of 10 ° with respect to the center line (9),

the clamping surface (17, 19) and the front side (3) enclose an angle Y of 20 to 30 °, preferably 23 ° to 27 °, in particular approximately 25 °,

- The center point (23) of the central axis (21) of the clamping groove (15) coincide with the center point of the center line (9) of the knife plate (1) and that

- The clamping groove (15) is point symmetrical to the center point (23) of the center line (9).

2. Knife plate according to claim 1, characterized in that it has mutually opposite along the two longitudinal edges (5, 11) of the knife plate (1) extending rake faces (7, 13).

3. Knife plate according to claim 1 or 2, characterized in that the clamping groove (15) has at least one, preferably two symmetrical to the central axis (21) formed clamping surfaces (17, 19).

4. Knife plate according to one of the preceding claims, characterized in that the length of the clamping groove (15) is selected such that it does not intersect the at least one rake face (7, 13), preferably both rake faces.

5. Knife plate according to one of the preceding claims, characterized in that the clamping groove (15) is closed all around and has a step on its narrow sides.

6. Knife plate according to one of the preceding claims, characterized in that the rake face (17; 13) by a chip breaker (14,14 ^* ) is limited.

7. Knife plate according to claim 6, characterized in that the chip breaker (14, 14 ') is substantially parallel to the longitudinal edge

(5,11) of the knife plate (1).

8. Knife plate according to claim 6, characterized in that the chip breaker (14, 14 ') extends at an angle to the longitudinal edge (7, 11) of the knife plate (1).

9. Knife plate according to one of the preceding claims, characterized in that the knife plate (1) is designed as a reversible plate.

10. reamer with - a base body (61),

- At least one guide bar (75, 77) inserted into the base body (61)

- At least one groove (64) embedded in the base body (61), - A knife plate (1) having at least one geometrically defined cutting edge (31, 35) inserted into the groove (64), in particular a knife plate according to one of claims 1 to 5 .

- One of the knife plate (1) in the groove (64) clamping device (43), which comprises a clamping claw (47) and a clamping screw (51), and with

an adjusting device (45) with which the protrusion of at least one cutting edge (35, 31) of the cutter insert (1) can be adjusted via the guide strips (75, 77) of the reamer (10),

characterized in that the adjusting device (45) has only one adjusting screw (55) which acts directly or via an adjusting part (57) on a first end of the knife plate (1), that the adjusting device can be blocked, and that the knife plate (1) with its second end lies directly against the base (65) of the groove (64).

11. Reamer according to claim 10, characterized in that the adjusting device (45) is arranged closer to the end face (83) of the reamer (10) than the clamping device (43).

12. Reamer according to claim 10 or 11, characterized in that the clamping claw (47) of the clamping device (43) has a clamping lip (49), the edge of the clamping screw (51) facing away from a parallel to the axis of rotation (63) of the reamer (10 ) extending imaginary horizontal (87) is inclined at an angle β of approximately 10 °.

13. Reamer according to one of claims 10 to 12, characterized in that the clamping claw (47) is inclined relative to an imaginary line (61) running perpendicular to the axis of rotation (63) of the reamer (10), the clamping lip (69) of which is closer to End face (83) of the reamer (10) is arranged as the clamping screw (51).

14. Reamer according to one of claims 10 to 13, characterized in that the cross-sectional profile of the groove (64) is adapted to the cross-section of the cutter plate (1).

15. Reamer according to one of claims 10 to 14, character- ized in that the groove (64) has a side surface (67) which serves to abut the cutter plate (1) under the action of the clamping device (43).

16. Reamer according to one of claims 10 to 15, characterized in that the base (65) of the groove (64) adjoins the side surface (67) at an angle> 90 ° and at an angle from the side surface (67 ) in the direction of the axis of rotation (63) the reamer (10) drops, which corresponds to the clearance angle of the cutter insert (1) inserted in the groove (64).

17. Reamer according to one of claims 10 to 16, characterized in that the base (65) merges into the side surface (67) of the groove (64) via an undercut.

18. Reamer according to one of claims 10 to 17, characterized in that the groove (64) has at its end facing away from the end face (83) of the reamer (10) a stop for the knife plate (1).

19. Reamer according to one of claims 10 to 18, characterized in that the groove (64) is a non-cutting process can be produced.