JP2675917B2 - Cutting tool for machining the inner and outer contours of a workpiece - Google Patents

Description

BACKGROUND OF THE INVENTION The invention starts from a cutting tool of the type described in the preamble of claim 1. In known cutting tools of this type (German Patent No. 3201508), one unique cutting tool is used for the purpose of aligning the cutting plate and clamping it on a supporting shoulder provided on the tool body. Screw members are provided. The cutting plate is arranged on a tensioning pawl, which is rotatably supported on the tool body about an axis which is axially and radially offset with respect to the cutting plate. The radial alignment of the cutting plate with respect to the tool axis is performed by rotating the tensioning pawl with respect to the tool body. In this case, the angular position of the cutting plate with respect to the tool axis is also forced to change. To clamp and secure the cutting plate or cutting edge to the support shoulder of the tool body, the tensioning pawl is pulled at a right angle onto the support shoulder, after which the cutting plate is held firmly on the tool body by a friction connection. Such an arrangement requires a relatively large amount of space and is therefore unsuitable for tools which attempt to machine very small holes. Moreover, the known arrangements are also unsuitable for high speed machining. This is because the cutting plate is not formally retained on the tool body to prevent radial ejection from the rotating tool.

Advantages of the invention The cutting tool according to the invention as defined in the characterizing part of claim 1 is distinguished by a particularly compact construction. In such a structure, in principle only one adjusting screw and one tightening nut are required for the positioning and clamping of the cutting plate. Therefore, the possibility of minimizing the tool and
Possibility of precision machining holes with small diameter.

The measures described in claims 2 and below enable an advantageous improvement of the cutting tool according to claim 1.

With the configuration of the tool according to the second aspect, it is possible to obtain the form-locking fixing of the cutting plate on the tool body. The tool thus configured is suitable for high speed machining. This is because the centrifugal force acting on the cutting edge during tool rotation acts on the axial tightening shoulder provided on the adjusting screw, which ensures that the form connection is maintained. The cutting plate is configured such that the centrifugal force vector acting on the center of mass of the cutting plate extends through the area of the support shoulder of the tool body. Further, the following advantages can be obtained. That is, after the tightening nut is loosened, the cutting plate can be swung outward from the plate seat portion and taken out without completely removing the adjusting screw and the tightening nut from the tool body.

In the tool according to the third to fifth aspects, the adjusting screw and the tightening nut can easily come close to each other, and therefore, the tool is particularly easily handled when exchanging the cutting plate, adjusting the position, and fixing the tightening. Become.

In order to prevent rotation of the cutting plate about an axis which lies perpendicular to the supporting shoulder of the tool body, the cutting plate is fitted on a shoulder provided on the tool body, for example cooperating with the end face of the cutting plate. Therefore, it can be firmly held. However, especially when the cutting plate is relatively long, it is advantageous if two adjusting screws are provided side by side for the purpose of adjusting the position of the cutting plate and tightening it. . In this case, it is also possible to adjust the cutting edge of the cutting plate obliquely with respect to the tool axis by a limited amount by different adjustments of the two adjusting screws.

A tool for machining a stepped hole is advantageous in that the cutting plate can be axially adjusted according to the features of claim 7.

BRIEF DESCRIPTION OF THE DRAWINGS In the following, embodiments of the invention will be described in detail with reference to the drawings. FIG. 1 shows a plan view of a friction machining tool or a precision drilling tool with a cutting plate aligned and fixed by two adjusting screws, and FIG. 2 shows a plan view of the tool shown in FIG. FIG. 3 is a side view, FIG. 3 is a sectional view taken along the line III-III of FIG. 2, and FIG.
FIG. 4 shows a cross-sectional view of the drilling rod of the tool along the line IV-IV of FIG. 1, FIG. 5 shows a plan view of the cutting plate of the drilling tool, and FIG. 6 shows that of FIG. A sectional view taken along line VI-VI is shown.

Description of the embodiment The tool has a piercing rod 10 as the body. The front end section 12 of this piercing rod is provided with a flat chamfer 14 and carries a cutting plate 16. This cutting plate is exchangeably fixed to the piercing rod 10 by the means described below. The cutting plate 16 is formed as a support for a cutting strip 18 made of a highly wear-resistant material. This cutting strip is fixed to the cutting plate 16 either rigidly or in some cases replaceably, for example via a dovetail guide. But the cutting plate
16 itself may be made of a wear resistant material to form the cutting strip directly or have cutting edges 20.

The piercing rod 10 is provided with a recess 22 in the area of the flat chamfer 14 (FIG. 4), which starts from the transverse plane 24 of the piercing rod 10 (FIG. 1) and at the front end of the piercing rod. Has reached. The recess 22 is bounded on one side by a longitudinal wall 28 which lies at least approximately in the diagonal plane 26 and on the other side by another longitudinal wall 30. This longitudinal wall is arranged at an acute angle a with respect to the diagonal plane 26 and forms a support shoulder for the cutting plate 16. In addition to the longitudinal recess 22, the through-planes 36 are provided in the transverse planes 32, 34 (FIG. 1), one through hole 36 each. This through-hole starts from a flat chamfer 14 and opens into the peripheral wall on the opposite side of the piercing rod 10. This through-hole is located above the bottom wall 38 of the recess 22 in each case with one relatively large diameter half-cylindrical section 40, which is followed by a relatively small diameter half-cylindrical section 42. Have The through hole further includes a bottom wall 38.
Below this, a perfectly cylindrical hole section 44 is formed. This hole section transitions into a half-cylindrical section 42 of the through hole 36 at the tightening shoulder 46.

The cutting plate 16 is formed as a prism. This prism is limited in particular by two side walls 48,50. These side walls are arranged relative to each other at the same angle a as the angle formed by the longitudinal walls 28, 30 of the recess 22 provided in the drilling rod 10. Both transverse planes 32,34 of the drilling rod 10.
The cutting plate 16 is provided with a half-cylindrical notch 52 at two positions having an axial distance corresponding to the distance. This notch extends from above to the tightening shoulder 54. Since the radius of the notch 52 corresponds to the radius of the section 40 of the through hole 36 provided in the drilling rod 10, the cutting plate
16 is inserted into the recess 22 of the piercing rod 10 and the side wall 50 is recessed.
Upon contacting the longitudinal wall 30 of 22, the pair of facing sections 40 and the notches 52 complement each other to form a cylindrical pocket.

Two adjusting screws 60 are provided to adjust the position of the cutting plate 16 by tightening it. Each of these adjusting screws has a head 62, a concentrically arranged threaded section 64 and an eccentric shaft section 66 located therebetween. This shaft segment is headed with an annular shoulder 68 at the top
Transitioning to 62, the eccentric peripheral surface of the shaft section forms a tightening shoulder 69. Threaded section 64 is tightening nut 70
Be screwed into. This tightening nut is the hole segment of the through hole 36.
It is rotatably supported by 44 and is supported by a tightening shoulder portion 46. The head 62 of the adjusting screw 60 is provided with one hexagonal hole 72 for fitting a wrench with a hexagonal head. The lower inner edge of the lock nut 70 also comprises an engagement surface 74 for a tool for rotating the lock nut. An adjusting screw 76 is provided to adjust the movement of the cutting plate 16 in the axial direction. The adjusting screw is mounted in a threaded hole arranged transversely to the tool axis 78 and presses the cutting plate 16 via a sphere 80.

The piercing rod 10 comprises two guide strips 82a, 82b in the area of the cutting plate 16. Like the cutting edge 20, these guide strips project slightly beyond the outer peripheral surface of the drilling rod 10 in the radial direction,
Is guided in the hole. Furthermore, the guide strip 82b located diametrically opposite the cutting edge 20 defines the diameter of the hole to be drilled, based on the distance of the guide strip from the cutting edge 20. The processing pressure is received via the guide strip 82a and directly transmitted to the work. Instead of the inserted guide strips, the individual peripheral sections formed between the segmented surface grinding parts provided on the drilling rod 10 can also take on the guide function. For the piercing rod 10,
Passages 84, 86 are provided for supplying cooling fluid to the cutting strip 18 and for leading out the cutting tip.

To insert, adjust and tighten the cutting plate 16, first rotate both adjusting screws 60 while firmly holding the tightening nut 70, and in this case, adjust the cutting plate 16 to the adjusting screw 60. Longitudinal wall of the piercing rod 10 which pivots under the head 62 and forms a support shoulder.
Abut on 30. Then, by rotating the adjusting screw 60, by changing the height position of the cutting plate 16 in the longitudinal wall 30, by extension, the radial distance between the cutting edge 20 and the tool axis, and in some cases also the angle with respect to the tool axis, It can be adjusted to the desired value. These values are related to the radial distance between the tightening shoulder 69 formed on the eccentric shaft section 66 of the adjusting screw 60 and the screw axis (diagonal plane 26, FIG. 4). The tightening shoulder is a cutting plate
16 is pushed more or less away from the screw axis, displacing the cutting plate upwards along the longitudinal wall 30.

To adjust or pre-adjust the desired cutting strip position relative to the tool axis, a piercing rod 10 is housed between the two tips of the adjuster which project into and engage both openings of the passageway 84. The amount of adjustment can be checked by two dial gauges. When the adjusting screw 60 is brought into the defined rotational position, the tightening nut 70 is firmly tightened while holding the adjusting screw 60 firmly.
At this time, the axial tightening shoulder provided on the adjusting screw 60
68 presses the cutting plate 16 firmly against the longitudinal wall 30 of the drilling rod 10. The mass center of gravity of the cutting plate 16 including the cutting strip 18, indicated by point M in FIG. 3, is set so that the centrifugal force vector acting on this cutting plate passes through the extent of the longitudinal wall 30 of the drilling rod 10. ing.

As an adjusting aid, markings may be provided on the adjusting screw 60 and on the surface area of the piercing rod 10 surrounding the adjusting screw. Further, stoppers may be provided on the adjusting screw 60 and the boring rod 10. This stopper limits the adjustment range of the adjusting screw 60.

The cutting plate fixing type according to the present invention can of course be used in a multi-tool or a multi-step tool for simultaneously machining an inner contour and an outer contour of a workpiece.

Continuation of the front page (56) References JP-A-58-126022 (JP, A)

Claims (7)

(57) [Claims] 1. A cutting tool for machining an inner contour and an outer contour of a work, comprising at least one cutting plate fixed to a tool body in a replaceable manner, the cutting plate being an adjusting screw. The cutting plate (16) can be radially adjusted with respect to the tool axis by a tightening nut and can be clamped and fixed to a supporting shoulder that absorbs a processing pressure by a tightening nut. , 18) for adjusting the radial position of the adjusting screw (6
0) also forms a tightening means for tightening and fixing the cutting plate (16, 18) to the support shoulder portion (30) provided on the tool body (10). A cutting tool for machining the inner and outer contours. 2. An a) adjusting screw (60) is arranged at an acute angle (a) with respect to a supporting shoulder portion (30) provided on a tool body (10), and a tightening nut (70) is provided. Screwed together,
The tightening nut is rotatably supported in one direction in the axial direction and supported by the tool body (10), and b) the adjusting screw (60) intersects each other at an acute angle (a). An axial tightening shoulder portion (68) directed to an intersection (b) between the screw axis of the screw (60) and a virtual extension line of the support shoulder portion (30) is provided, and the tightening shoulder portion is , Pressing the corresponding shoulder portion (54) provided in the cutting plate (16, 18) in contact with the supporting shoulder portion (30) and directed in the angular opening direction on the side opposite to the intersection, in the axial direction. C) the adjusting screw (60) comprises a longitudinal section (66) arranged eccentrically with respect to the screw axis, the eccentric circumferential surface of the longitudinal section having a radial tension. A constant shoulder portion (69) is formed, and the tightening shoulder portion is aligned with the screw axis provided on the cutting plate (16, 18) in contact with the supporting shoulder portion (30). 2. The cutting tool according to claim 1, wherein the corresponding radial shoulders (48) extending parallel to each other are pressed. 3. The tightening nut (70) is arranged at the end of the adjusting screw (60) directed to the intersection (b), and in the angular opening direction on the side opposite to the intersection. The cutting tool according to claim 2, which is axially supported by the tool body (10). 4. The tightening nut (70) is a tool body (1).
The cutting tool according to claim 3, which is fitted in a cylindrical notch (44) which is provided in (0) and is open toward the outside. 5. An axial tightening shoulder portion (68) of the adjusting screw (60).
Formed at the transition from a screw head (62) with an engagement surface (72) for an adjusting tool to an eccentric shaft section (66) forming a radial clamping shoulder (69) The cutting tool according to any one of claims 2 to 4, which is provided. 6. The adjustment screws (60) arranged side by side are provided for the purpose of aligning and clamping the elongated cutting plates (16, 18), the adjustment screws (60) being arranged side by side. The cutting tool according to any one of 1. 7. The cutting plate (16, 18) is a tool body (1).
0) an adjusting element (76) rotatably mounted on the tool body transversely to the longitudinal extension, and an element (80) for converting lateral movement into longitudinal movement, preferably a sphere. 7. The cutting tool according to claim 1, wherein the position of the cutting tool is adjustable in the axial direction.