DD158366A1 - CLAMPING DEVICE FOR MILLING CUTTING PANELS TO PLANFRAESKOEPFEN - Google Patents

Abstract

The inventive clamping device is used for clamping of ground, undrilled inserts on Planfraeskoepfen, Stirnfraesern and the like, wherein the occurring during milling centrifugal forces are used directly for Spannkraftverstaerkung. The aim of the invention is the optimal reduction of the loading and setting of indexable cutting tools. In a Fraeskopfgrundkoerper a provided with ground indexable insert seat ring is attached. Each indexable insert is axially supported by angeflaechte Stuetzrollen and constantly pressed in by clamping lever hinges clamping lever by means of their Spannhebelkoepfe due to their geometry constantly in their indexable insert recording by the clamping lever ends are constantly under spring pressure. The cocking lever ends have over the Spannhebelkoepfen larger mass and length, so that their centers of mass are further removed from the clamping lever fulcrum than the Spannhebelkoepfe. During tool rotation, this results in different centrifugal moments on the clamping lever ends or heads, the difference of which is exploited for the clamping force increase for the indexable inserts. The higher the milling tool speed, the greater the contact pressure on all indexable inserts against their recordings.

Description

Clamping device for indexable inserts on face milling heads Field of application of the invention

The invention relates to a clamping device for inserts on Planfräsköpfen, face milling cutters and the-5 'same, the centrifugal forces occurring are used directly for • Spaiinungsverstärkung.

Characteristic of the known technical solutions

It is known that centrally drilled indexable inserts are secured by means of screws and Gev / co-nuts non-positively and positively on the milling head. To set up the indexable inserts on a common trajectory diameter is usually the bore of the indexable inserts larger than the Schraubendtirchmesser. In addition, the clamping and tension of the internal stress indexable inserts requires the creation of appropriate preconditions for indexable insert clamping and the use of precision ground indexable inserts. In addition, undrilled indexable inserts are applied, which are clamped by means of wedges non-positively with the tool body and clamped. 'These solutions require a great deal of time, especially when adjustments have to be made in the axial and radial directions'. In addition, there is a high manufacturing outlay in the production of such tools, especially for the small lever

elements for fastening, Xagefixierung and tension of the indexable inserts. The positive connection with the tool body is achieved only by precision-ground indexable inserts and corresponding receiving surfaces.

enough.

Other options for tensioning indexable inserts include the use of spring elements for quick clamping and release of indexable inserts. It will be

- Clamping wedges between indexable inserts and tool body loaded or relieved by spring force. The disadvantage here is, .Daß that the spring force of the clamping wedges acting on spring elements decreases over time, so that a! Nachspannen is required. Finally, the clamping of the indexable inserts is no longer sufficient to be immovable in their intended dynamic load. Able to fix. The result is workpiece scrap and tool breakage.

Moreover, in the DDWP 89 "297 a chuck is described on machine tools, in which the clamping forces are generated by the generated during rotation of the clamped work centrifugal forces, that in the cavity formed by the chuck body, the tapered sleeve and the known collet steel balls are arranged, to achieve sufficiently large centrifugal forces, which are forwarded for the purpose of workpiece clamping and acting on the collet.

Object of the invention

The aim of the invention is to minimize the assembly and set-up time of rotary cutting edge milling tools, such as face and shoulder milling heads, to a minimum »

Explanation of the essence of the invention

22 9 3 93 7

The invention has for its object to provide a clamping device for indexable inserts in Planfräsköpfen and the like, wherein the. occurring centrifugal forces on specially designed lever directly to the clamping force gain be exploited.

According to the invention, this object is achieved by utilizing the resulting centrifugal forces for clamping purposes and use

of ground, undrilled indexable inserts and geschilffenen receiving surfaces, which are located in a mounted on a Fräskopfgrundkbærper seat ring, solved by 'that the device contains essentially clamping lever which are rotatably mounted by means of a respective bearing pin in a clamping lever hinge and after their clamping lever ends are set by a respective pressure piece with compression springs so under spring pressure, that the clamping. As a result of their geometry, levers with their tension lever heads constantly press on one indexable insert. The pressure pieces with compression springs' and retaining rings are arranged in a flange which is fitted in a known Fräskopfgrundkörper and secured by screws to it. The Y / end cutting plates are each inserted into ground shots of a fitted and screwed into the Fräskopfgrundkörper seat ring and are supported by angeflächte support rollers in the axial direction. The cocking lever hinges are housed in the milling head body by means of 'fitting and screwing. The clamping lever ends have over the tension lever heads a larger mass and a greater length. As a result, the center of gravity of the clamping lever ends is further removed from the pivot point of the clamping lever, as the center of gravity of the clamping lever heads, whereby upon rotation of the milling tool different centrifugal moments on the tensioning

2 ^ / β-

Adjust the lever heads and at the clamping lever ends, the difference of which is utilized for a clamping force increase at the indexable inserts. The higher the speed of the Preswerkzeuges, the larger the additional

5. Tension on the indexable inserts. For optimal transfer of the clamping forces from the clamping lever to the indexable inserts and to compensate for tolerances of the indexable insert geometry, the clamping elements are among the

• I ngs- and transverse axes of the clamping lever at the angles «<,, /?

and ^ inclined, preferably e C - 7 °, β - 5 ° "and ^ = 8 °." To achieve a favorable chip flow, a concave chip discharge surface is incorporated in the clamping lever heads.

embodiment

The invention will be explained in more detail by an embodiment with reference to 8 drawings. , Show it! ,

Fig. 1g the clamping lever in the front view Fig. 2i the clamping lever in the side view Fig. 3t the clamping lever in plan view Fig. 4i two details on the clamping lever head · Fig. 5 »a view of the entire tool from below Fig. 6j is a side view of the tool in section along AA. ,

7s is a side view of the tool in section along B-B ··· ... · ...

8t shows a partial section of the tool along C - C. A seat ring 2 is fastened in a milling head basic body 1 with ground receptacles 17 for also ground, undrilled indexable inserts 15. Each indexable insert 15 is inserted into its ground

229393 7

Receptacles 17 supported by angeflächte .Stützrollen 14 in the axial direction and always urged by a respective clamping lever 4 by means of an associated clamping lever head 5 due to ν its geometry on its seat 17 by rotatably mounted the clamping lever · 4 each by means of a bearing pin 13 each in a clamping lever hinge 12 are and placed over their clamping lever ends 7 by pressure pieces by means of compression springs 10 continuously under Pederdruck

- ·. are. The pressure pieces 9 with compression springs 10 and Siche

'10 tion rings 11 are arranged in a flange 3, which is fitted into the Fräskopfgrundkörper 1 and secured by screws 16 to him »The clamping lever hinges 12 are accommodated by means of fit and screw directly in the milling head body 1. The clamping lever ends 7 have over the Spannhebelkb'pf s 5 a greater mass and -large length, thereby v / ird that the centers of gravity of the clamping lever ends 7 are further removed from the fulcrum of the clamping lever 4 than the'massenschwerpunkte the Spannhebelköpfe 5 · When turning the .Präswerkzeuges thus arise different Pliehkraftmomente 'at the clamping lever heads 5 and at the clamping lever ends 7, the difference is utilized for a Spannkrafterhöhung on the indexable inserts 15; the higher the speed of the milling tool,. Thus, the contact pressure on the indexable inserts 15 against their receptacles 17 increases. In order to ensure optimum transfer of the clamping forces from the clamping levers 4 to the indexable inserts 15 and to compensate for tolerances in the geometry of the indexable inserts 15, the clamping lever heads 5 are in

Relative to the longitudinal and transverse axes of the tensioning levers 4: inclined at the angles oL , β and J ^ , where preferably et = * 7 °, β. = 5 ° and J * - 8 ° Spanablaufes are incorporated in the clamping lever heads 5 concave chip discharge surfaces 8.

Claims (2)

2 0 π ο π ^ * f Cn ^ f \ £ Jf ζ ^ ί ^ i invention claim 1 · Clamping device for indexable inserts ah Planfräsköpfen, face milling cutters and the like using the resulting centrifugal forces for clamping purposes and use of ground undrilled indexable inserts and ground receiving surfaces, which are located in a mounted on a "Fräskopfgrundkörper seat ring, characterized in that the device substantially as many 'Clamping lever (4), as the cutting tool has cutting contains, by means of .lagerstiften (13) in a Fräskopfgrundkörper (1) fitted and screwed clamping lever hinges (12) rotatably mounted and according to their • clamping lever ends (7) through in a the Fräskopfgrundkörper (1) fixed flange (3) arranged pressure pieces (9) with compression springs (10) and retaining rings (11) are set under spring pressure so that they constantly with their clamping lever heads (5) due to their geometry on each indexable insert 20- (15) press, in the ground shots (17) of a in the Fräskopfgrundkörper (1) fitted and screwed seat ring (2) are inserted and supported by angeflächte support rollers (14) in the axial direction, wherein the clamping lever ends (7) opposite the clamping lever heads (5), in which are incorporated to achieve a favorable Spanabiaufes concave chip discharge surfaces (8), a greater mass and length for generating different centrifugal moments on the clamping lever ends (7) or 'to the clamping lever heads (5) with rotating milling tool have and the centrifugal force differential of the clamping force increase at the indexable inserts (15) is used. 229 2. Clamping device for indexable inserts on "Planfräs- 'heads according to item 1, characterized in that for the purpose of optimal transfer of the clamping forces of the clamping levers (4) on the indexable inserts (15) and to compensate for tolerances of We.endesender geometry the tension lever heads (5) to the longitudinal and transverse axes of the clamping levers (4) are inclined at the angles cL , β and ^ , wherein preferably the angle values for ßC «7 °, for β = 5 ° and for l * = 8 ° amount.