Technical field

The invention relates to a cutter-holder for the turn¬ ing of polygonal surfaces. The device is well ^" balanced, its eccentricities can he simultaneously, resp. auto- matically adjusted and using with accessories, it can he rendered suitahle for the machining of finned and relieved surfaces.

Background art

Por the machining of polygonal surfaces machines have ^" been well known, which are producing epicycloid and ypocycioid surfaces ^" by means of a rotary motion or ^" by the superposition of a rotary motion and a translat- iona motion. Any of the motions can he performed either ^" by the tool or the work piece. With machines, where the tool is put into motion, the drawhack of the versions provided with revolving tools lies in, that they do not represen-fc a universal solut¬ ion. Bores and tongues cannot he produced, the outer surfaces having ^" been produced are discontinuous, their accuracy is insufficient, ^" because either the work piece has to he divided periodically or several adjusted turning tools are to he used.

The drawback of the known verions with slides, with the machines, ^■ .•.-here the tool is put into motion, e. g. the solution having ^" been ^' described in the patent Eϋ-PS

91819 lies in that ^" the linear slides"being controlled by means of cams, paths or actuated wit an eccentric, are unbalanced, the power transmission via the rollers

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between the control elements and the slide is weak, accordingly, only a slow drive with a low efficiency becomes possible.

The lathes with a linearly actuated slide, at which 5 the control cam is followed by the slide in a copying system, are working with a low capacity, because at the high speeds the feeler is leaving the cam behind, furtheron the problem connected to the unbalanced state of the slides has to be confronted with. The known.

10 versions of the machines, where the v/ork piece is moved /e. g. the solution having been described in the patent Kϋ-PS 156 607/ are well suitable for processing smaller work pieces. With these mach nes the majority of the unbalanced mass is fonαed by the work piece. In

15 course of changing over to an other type of work piece and in course of cutting the mass of the work piece is varying, being utmost infavourable in respect to the balanced state.

With the known machines adjustment of eccen-fcricity 20 represents a time-consuming process.

Due to the imperfection of the known machines enumerated above, machining of polygonal surfaces is performed rarely on automatized lathes, as e. g. capstan lathes, lathes with fly-cuirfcers, program-controlled lathes,

25 HC-lathes and machining lathe-centres, in addition to this, the polygon-lathes do not represent the members of the special lathe-families, e. g. they are not used with backing-off lathes. These features account for the fact, that inspite of the advantages of the application of

30 polygonal surfaces from the technical point of view, they are not widely used.

Disclosure of Invention

The aim of the invention is to develoτ> a cutter-holder

without unbalanced masses producing large dynamical forces and moments, which can be used with a high productivity .for cutting work pieces of any weight and size, simultaneously the number of the surfaces to be produced is infinite, as the eccentricities can be adjusted uickly and accurately, changing-over takes place without difficulty and whic enables the incor¬ poration of the polygόn-lathe into any production- line built-up of the known machine-types. The cutter-holder according to the invention being suitable for processing polygonal surfaces is solving the task by being provided with a cutter-holder with adjustable eccentricity having been supported in bearings on the actuating camshaft, with a further camshaft keep- ing the cutter-holder in a position being parallel with the original adjusted position or being provided with a structural part for preventing the swivelling motion; furtheron on one or more camshafts journals having been displaced by ISO ⁰ in relation to the cutter-holder's journals are arranged; the cutter-holder according to the invention is also provided with a centralized resp. automatized regulating device for the simultaneous adjustment of the balancing mass actuated by said journals and of the eccentricity of the eccentrics. A further characteristic of the cutter-holder according to the invention lies in, that the journals of the second camshaft having been connected to the cuiter- holder and the balancing mass, respectively, are support¬ ed in crank pads sliding in a link guiding. A further characteristic of the cuttεr-hclder according to the invention lies in, that the structural part serving for the prevention of the swivelling motion is provided with a double-armed lever and the anis of

rotation thereof is supported in bearings in the base body, while one end of the lever is connected to the cutter-holder via the articulated coupling rod and the other end is connected to the balance bridge through the articulated coupling rod having the same size, as the previous one.

According to a further characteristic of our invention, on the two ends of the double-armed lever of the structural part preventing turn-off, crank pads supported in link journals are arranged, while one of the crank pads is led in the link guiding formed in the cutter-holder and the other crank pad is led in the link guiding formed in the balance bridge _*

A further characteristic feature of the cutter-holder according to the invention lies in, that the base body of several cu -feer-holder structures is formed as a capstan, on which, between the traditional cutter-holders a cutter-holder each according to the invention.is fixed and two cutter-holders each accosting to the in- vention having been displaced by 150° pair-wise are arranged on the opposite sides of the capstan; the cam¬ shafts of the cutter-holding devices lying opposite to each other are rotating in the same direction, -however, with an opposite eccentricity, at last the camshafts of the two pairs of cutter-holders are rotating in the opposite direction.

The cutter-holder according to the invention can be further characterized by the arrangement, in which the structural part preventing turn-off incorporates an element preventing the turning-cff motion, and said element is provided with two straight rib guides lying normal to each other; one of the rib guides is connected to the base body, while the other is sliceabl^r connected

to the cutter-holder and the rib of the cutter- holder can be pulled out from the guide normal to the rib.

A further characteristic of the cutter-holder according to the invention iies in that one end of the camshaft carrying the cutter-holder is fixed as a centering cone or cylinder into the driving spindle by using a quick-clamping method. -

A further characteristic of the cutter-holder according to the invention lies in that the structural part for the simultaneous adjustment of the eccentricity belong¬ ing to the eccentrics having been arranged next to each other on the same shaft, is formed with eccentric journal surfaces, on the ournal surfaces there is an eccentric sleeve each, supported in bearings betv/een the single sleeves rings are arranged for the trans¬ mission of the rotating and adjusting motion and on the rings, on the frontal surfaces thereof facing each other there are the ribs lying perpendicularly to each other and the ribs of said rings are extending into the grooves having been formed on the frontal areas of the rings.

A further characteristic of the cutter-holder according to the invention lies in, that the simultaneous resp. automatized eccentricity adjusting device belonging to more camshafts runn ng parallel with each other is provided v/ith releasable sleeves having been supported in bearings on the camshafts, furtheron said device is provided v/ith wrenches engaging v/ith the orienting notches or v/ith retaining blocks; the device also com¬ prises a measuring element for the control of the relative position of the sleeves and the camshaft, as well as adjusting means for changing over to the slow adjusting or to the quick operational number of

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devolutions.

The cutter-holder according to the invention may be further characterized by the centering cone or cylinder of the camshaft.

5 In accordance with a further characteristic feature of the cutter-holder according to the invention, into the centering cone resp. cylinder of the camshaft a rotating cutter-head v/ith fly-cutters has been fixed, v/hile the casing of the cutter holding device has been 10 built onto the underlay unit driving the second camshaft and defining the normal or inclined position of the camshaft in relation to the axis of the v/ork piece.

A further characteristic of the cutter-holder according to the invention lies in, that it Is provided with a 15 shaft having been fixed into the centering cone or cylinder of the camshaft v/ith one or more bevel gear assemblies for transferring the rotating motion from the shaft, v/ith a spur gearing and a main spindle v/ith a vertical or inclined axis.

20 In accordance with a further characteristic, the cutter- holder according to the invention is provided with a control cam having been fixed into the centering cone or cylinder of the camshaft with a roller having been pressed onto the surface of the control cam by means

25 of a spring, v/hile the shaft of the roller is fixed in the linearly moving slide actuating the cutter.

Brief Description of Drawings

The cutter—holder according to the invention for processing polygonal surfaces will be described in 30 detail by means of preferred embodiments, by the aid of the accompanying drawings, wherein:

O H /

figure 1 is schematically shov/ing the principle ' of the structure and operation of the cutter-holder according to the invention, provided with the balancing part and two camshafts, figure 2 is showing the schematical top-view of the cutter-holder operated on the principle according to figure 1, figure 3 is shov/ing a further embodiment.of the • cutter-holder according to the invention also comprising the balancing part and - * the two camshafts, figure 4 is a schematical top-view of the cutter- holder according to figure 3, figure 5 is shov/ing a further embodiment of the cutter-holder according to the invention having been provided v/ith the balancing part, figure 6 is shov/ing the cutter-holder as illustrated in figures 1 and 2 but without the separate balancing parts, combined with an eight- position capstan; on the capstan four traditional cutter-holders and four cutter- holders according to the invention are arranged, figure 7 an embodiment of the cutter-holder is shown, at which changing of eccentricities may be performed by the quick change of the eccentrics, figure 8 is shov/ing schematically the structural solution being suitable for the simultaneous and joint adjustment of the train of eccentrics lying next to ea-ch other on the sha t, figure 9 is shov/ing the principle of the adjustment

of the eccentrics of the structure having been ill strated in figure 8, in view lying normal to the shaft, figure 10 is shov/ing schematically the embodiment being suitable for the simultaneous automatic adjustment of the eccentrics lying on the two camshafts, figure 11 is showing schematically the completed embodiment of the invention having been changed over to the processing of ribbed work pieces having different profiles,. by using fly-cutters, figure 12 is showing schematically a further complet embodiment of the invention for processing the ribbed work pieces having different profiles, by using fly-cutters, figure 13 is shov/ing schematically the ^' completed embodiment of the cutter-holder according to the invention having been changed over to backing-off, figure 14 is shov/ing the scheme of the drive of the cut er-holder, figure 15 is a summarizing scheme showing the modularly obtainable embodiments of the invention.

• Best Mode of Carrying Out the Invention

With the theoretical solution to be seen in figure 1 the v/ork piece 1 is performing a steady rotating motion around the shaft 2. The cutter 4 chucked into the cutter- holder 3 is moved ~cγ the camshafts 5, 6 in a translational circular motion. The camshaft 5 is performing an uni¬ directional steady rotating motion with a permanent

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number of revolutions around the shaft 7, while the camshaft 6 is performing the same motion around the shaft 8, while the angular velocity of the rotating motion is higher, than the angular velocity of the v/ork piece 1, and as many times higher, as the polygon- number to be produced according to the prevailing requirements. The journal 9 of the camshaft 5 is support¬ ed in bearings in the cutter-holder 3, v/hile the journal 10 of the camshaft 6 is supported in the crank pad 11. The crank pad 11 may slide in the link guiding 12 in the cutter-holder 3, however, this sliding movement can take place only then, if the eccentricities or synchron positions of the 'journals 9, 10 of the cam¬ shafts 5 _> 6 are different. The camshaft 5 rotating around the shaft 7 has a further eccentric journal 13 having been displaced by 180° in relation to the journal 9. The eccentric journal is support ed in bearings in the balance bridge 14. At the same time, the camshaft 6 rotating around the shaft 8 is also pro- vided v/ith an eccentric journal 15 having been displaced by 180° in relation to the journal 10. The eccentric journal 15 is supported in bearings in the crank pad 16. , The crank pad 16 may slide in the link guiding 17 in the balance bridge 14. Hov/ever, this sliding motion becomes possible in this case only, if the eccentricities or synchron positions of the eccentric journals 13, 15 of the camshafts 5, 6 are different. The balancing mass 18 is also attached to the balance bridge 14.

As it is to be seen in figure 2, the shaft 7 of the ca - shaft 5 is supported in bearings in the casing 19, the shaft 8 of the camshaft 6 is also supported in the casing 19, shich itself is fixed on the place of the rear cutter- holder of the lathe. The shaft 8 is driven by the telescopic cardan shaft 20, v/hile the shaft 7 is driven from the

shaft 8 via the gears 21, 22, 23. The tooth numbers of the gears 21 and 23 are identical, accordingly, the shafts 1, 8 are performing a rotating motion with identical numbers of revolutions and in the same direction.

With the embodiment according to figure 2 for actuating the cutter-holder 3 the camshaft 5 has been provided with two eccentric journals 9-1 and 9-2, respectively, one being arranged on one side of the casing 19, the other one on the other side thereof. The cutter-holder 3 is enclosing the casing 19 from the front in a bridge-like manner. At the same time, the camshaft 6 is provided v/ith but one single journal 10 which is supported in bearings in the crank pad 11. By this arrangement, through the link guiding 12 the turn-off of the cutter-holder 3 may be prevented. The camshaft 5 is provided v/ith further two eccentric journals 13-1, 13-2, by the aid of which the balance bridge 14 is put into motion, one of the journals is arranged before the cutter-holder, the other one ben nd. On the top the balance bridge 14 is arranged in a bridge¬ like manner above the cutter-holder 3. Turning-off of the balance bridge 14 is hindered by the journal 15 of the camshaft 6, having been supported in bearings in the crank pad 16. In order to promote understanding, the eccentricities in figures 1, 2 and in the following ones are enlarged. The chucking part of the cutter-holder is shown in the rough only; instead of a simple chucking, cutter-holders with chucking devices enabling quick-clamping may be also used.

The advantageous feature of the theoretical solution of the figures 1 and 2 lies in, that the translational circular motion is enabled by bearings of high efficiency. The crank pad 11 does not slide normally in the link

guiding 12, the possibility of sliding serves for the operational safety. The complete elimination of sliding in practice confirms the good efficiency of the solution according to the figures 1 and 2. A further advantage lies in that the distance of the shafts 7 and.8 may be optionally selected, accordingly, an utmost advantageous proportion of the lever arms may be obtained against the moment of the cutting force.

Due to the fact that the distances of the eccentric journals 9-1 and 9-2, i. e. the distances of the eccentric journals 13-1 and 13-2 are chosen as maximums within the dimensions of the cutter-holding device, the advantageous proportion of the lever arms against the moment of the cutting force may be observed not only in the plane lying perpendicularly to the axis of rotation, but also in the planes traversing perpendicularly the shaft 7 of the camshaft 5. As a consequence, the cutter-holder according to the invention may be well used even with high cutting forces and high outputs. The number of revolutions of the camshafts should be as many times higher, than the number of revolutions of the work piece, as the number of polygons. With the up-to-date lathes the number of revolutions of the main spindle is high,this involves, that in order to be able. to reach maximal cutting speeds in course of the turn¬ ing process, the number of revolutions of the camshafts is to be selected as high as possible within the dynami¬ cally possible limits. The upper limit value of this maximal number of revolutions depends mainly on the balanced state of the masses performing the translational circular motion.

The balanced state is ensured by the balance bridge 14 moving in a counter-cycle in relation to the cutter-

holder 3, v/hile the accuracy of the balancing will be defined by the balancing mass 18 having been mounted onto the balance bridge and the magnitude of which is determined by the accurate weighing of the masses 5 to be balanced.

With the embodiment shown in figure 3 and 4 the cam¬ shaft 5 has one single journal 9, having been supported in bearings in the cutter-holder 3. The camshaft 6 has also a journal 10, having been supported in bearings

10. in the cran pad 11, which again is led in the link guiding 12 of the cutter-holder; furtheron the camshaft 6 is provided with an eccentric journal 15 having been displaced by 180° and of the same eccentricity, as that of the journal 10, and which is supported in bearings

15 in the balance bridge 14. The hinge 25 of the coupling rod 24 is supported in bearings in the double-armed lever 27; the double-armed lever 27 is turning around the stationary axis 28 of rotation, v/hile its hinge 29 is connected via the coupling rod 30 and the hinge 31

20 to the cutter-holder 3. The tv/o arms of the double-armed lever 27 are of the same length, accordingly, the vertical component of motion of the cutter-holder 3 is trans¬ ferred in a counter-cycle onto the balance bridge 14, v/hereby turning-off of the balance bridge 14 can be

25 also prevented.

Prom the figure 4 it becomes obvious, that the cutter- holder 3 and the balance bridge 14 of the embodiment shown in figures 3 and 4 are arranged on one side of the casing 19, as a consequence, less eccentrics are 30 needed and it represents a more simplified solution, than that having been illustrated in figure 1 and 2, respectively. Prom the point of view of the accurate bearing support of the cutter-holder It is to be con¬ sidered as utmost advantageous that -he camshaft 5 has

only one single eccentric journal.

The camshafts 5 and 6 of the solution according to figure 5, as well as the connection thereof to the cutter-holder 3 and the balance-bridge 14 are in compliance with the solution having been outlined in connection with figures 3 and 4.

The hinge 26 of the double-armed lever 27 tilting around the stationary axle of rotation 28 is supported in bearings in the crank pad 33 led in the link guiding 32 of the balance bridge 14, v/hile the hinge 29 of the double-armed lever 27 is supported in bearings in the crank pad 34 led in the link quiding 35 of the cutter- holder 3.

The advantageous features of the solution having been described in figure 5 a e the same, as those of the solution according to figures 3 and 4, v/ith the difference, that because of the crank pads 35, 54 having been in¬ stalled instead of the coupling rods 24 and 30, the heights are smaller. In figure 6 a cutter-holder system having been arranged on an eight-position capstan is to be seen, consisting of four cutter-holders according to the invention and four traditional cutter-holders. The cutter-holders 37 on the capstan 36 serve for normal turning processes. In ^' course of turning polygonal sur aces the cutter-holders 58, 39, 40, 41 are performing a translational circular motion in such a manner, that the forces of inertia result¬ ing from the motions are balanced within the capstan 36, accordingly, instead of supplementary and balance masses mutual compensation is performed by the cutter-hol ders themselves.

The camshafts of the cutter-holders 38, 39 are rotating in the same direction, however, wit an opposite eccentric!

Within the single cutter-holders /cutter-holder pairs/ the radial components of the forces of inertia are com¬ pensated, while -fh- tangential components are transmitting a moment onto the shaft of the capstan. The camshafts of the cutter-holders 4 ^' C, 41 are rotating v/ith the same number of revolutions, as the camshafts of the cutter-holders 38, 39, but in an opposite direct¬ ion. The cutter-holders 38, 39 and 40, 41, respectively, are arranged on the opposite sides of the capstan 36, having been displaced by 180° in relation to each other. The radial components of' the forces of inertia induced by the cutter-holders 40 and 41 are also mutually compensat¬ ed, v/hile the moment resulting from the tangential com¬ ponents is compensating the moment resulting from the tangential components of the forces of inertia of the cμtter-holders 38 and 39.

In course of turning polygonal surfaces, change of tools may become necessary. With the embodiment shown in figure 6 the four cutter-holders 38, 39, 40, 41 can be pre-set for the diverse eccentricities, as a consequence, simul¬ taneously v/ith the change of the capstan, automatical change of the eccentricities may be performed quickly and v/ith a high accuracy. The masses of the four cutter- holders are different. The larger eccentricities are adjust- ed on the cutter-holders of smaller masses and in order to be able to obtain accurate compensation, in the cutt er- holders supplementary masses may be used.

V/ith the embodiment shown in figure 6, the camshafts of the cutter-holders are driven by the central gear 42, that is, the cutter-holders 38 and 59 are directly driven by the gear 43, whereas the cutter-holders 40 and 41 are driven via the intermediate gear 44.

The advantageous feature of the solution according to

figure 6 lies in, that due to the balanced state of the system the requirements regarding to the high-output drives with a high number of revolutions may be met, furthermore, ^' as a consequence of the possibility of the ^' quick change of eccentricities the requirements relating to automatization may be also met.

With the embodiment shown in figure 7 "the pre-set eccentrics or the eccentrics having been set for a constant value can be exchanged together v/ith the cutter- holders. With the embodiment shown in the figure the drive unit 44a is fixed onto a cross tool carriage. The number of revolutions of the spindle 45 is as many times higher, than the number of revolutions of the main spindle of the lathe, as the number of the polygons. Into the bore of the spindle 45 a centering cone 46 may be insert¬ ed. The eccentric journal 47 is connected to the cone 46, in relation to the centering cone 46 the journal 47 has a given or adjustable eccentricity. The journal 47 is supported in bearings in the cutter-holder 3. The-rotation of the cutter-holder is prevented by the element 48. The rib 49 of the cutter-holder 3 may slide in the notch having been machined in the element 48, simultaneously the rib 50 of the element 48 is sliding resp. freely moving in the notch in the base body. The notch in the element 48 and the notch in the base body 44b are lying perpendicularly to each other. The centering cone 46 and the belonging journal 47 can be easily pulled out from the spindle 45 2 d. they can be replaced by any other structural part, either with a similar or a different eccentricity, or carrying any other tool serving for a different purpose. In such a manner,' automatical adjust¬ ment of eccentricity and the exchange of tools can be well co-ordinated. Into the centering cone of the spindle 45 not only the tools being suitable for process¬ ing polygonal surfaces, but also tools for processing

with fly-cutters, for boring, milling etc. may be inserted. The driving shaft of any.type of apparatus may be also connected to the centering cone.

The embodiments shown in figures ^' 1 to 5 are provided ^'■ with. ore, than one camshaft, as a consequence, when adjusting an eccentricity each, more eccentrics are to be used resp. adjusted. The methods of adjusting the eccentricity is not shown in said figures. In order to be able to shorten the time needed for the adjustment, it seems to be expedient to perform the adjustment of all the eccentrics simultaneously. In course of the adjustment of the eccentricity the requirement has to be met, in so far as the eccentricities- of the eccentrics actuating the balance bridge 14 are to be adjusted to the same extent, but in a different sense, than the eccentricities of the eccentrics actuating the cutter- holder 3. Different modes of adjustment are needed, _in dependence, v/hether the camshaft i. e. the eccentrics - being technically equivalent v/ith the camshafts - are arranged on the same axis, or the camshafts are displaced in relation to each other.

The solution having been Illustrated in figure 8 is well suitable for the simultaneous adjustment of the eccentricity of the row of eccentrics arranged next to each other, when the sleeves having been formed as eccentric discs are to be adjusted in the opposite sense. The adjusted confining eccentricities are enclosing an angle of 180° in every position.

The principle of the adjustment is shown in figure 9, in a view lying normal to the axis. The simplified scheme is shov/ing only the positions of the idlines, i. e. the path having been covered in course of the adjustment.

On the internal shaft 51 the surfaces are shov/ing three different eccentricities. The eccentricities of the two

outer journals equal to zero, their shaft is formed by the central shaft 52. As advancing inwards, the tv/o journals are provided vith the shaft 53, v/hile the shaft 54 belongs to the central journal. On the eccentric journals the sleeves 55, 56, 57 and 58 are arranged, serving for the adjustment of eccentricity. Said sleeves are interconnected by the rings 59, which are formed in a similar manner, as the floating disc of the Oldham-typ switch. The rings are transferring the rotating motion from one sleeve to the other.

In figure 8 the sleeves 56, 57 are adjusted to the zero- eccentricity, in this case the central shaft 2 is form¬ ing the centreline of the outer surfaces of the sleeves. In this position the outer surfaces can be prepared and ground in a simple and easy manner. When the sleeves are rotated in clockwise direction, the shafts of the sleeves 55 _> 57 are advancing from the center /figure 9/ around the shaft 53 along the path 60, at the same time the axis of the outer surface of- the sleeve 56 is chang- ing its position along the path 61. When the angular displacements are equal, the eccentricities of the neighbouring sleeves will be also equal after the single adjustments, however, v/ith an opposite sense.

The eccentricity of the sleeve 58 is always equal to zero. The solution having been Illustrated in figure 10 enables the simultaneous adjustment of the eccentricities of the camshafts running parallel, however, displaced, v/ith each other. In the figure the balance bridge is not illustrated. V/ith the embodiments shown in figure 10, the adjustment of the two shafts and the row of eccentrics thereon is performed in such a manner, that the eccentric sleeves 62, 63 are stopped in a given position, e. g. so, that

either they are coupled by means of a special wrench 64, or automatically oriented and fixed in course of the slow rotation, thereafter the connection vith the cam¬ shafts is released, v/hile the camshafts are rotated in a low adjusting circular motion until reaching the required position; the sleeves are fixed to the cam¬ shaft, i. e. in case of a discrete divider they are oriented and fixed.

After having stopped all the eccentric sleeves in a given position, the entire task of adjustment is simplified to a simple task of division.

At the embodiment to be seen in figure 10 the gear 65 may be driven from the gear 66 or the gear 67. When the gear 65 is engaged v/ith the gear 66 an operational quick- drive suitable for processing will be obtained, while in case of an engagement with the gear 67, driving Is taking place from the worm gears 68, 69. The gears 21, 22, 23 may be rotated in both engagements via the gears 67-65. In course of the slow adjusting motion, initially the camshafts 5 _» 6 are co-rotating v/ith the sleeves 62, 63, whereas in a given position the sleeves are fixed against rotation, e. g. by means of the special wrench 64 engaging with the orienting notches on the sleeves 62, 63. Subsequent the coupling between the camshafts and the sleeves is to -be released and in course of the further adjusting motion the camshafts 5 and 6 are rotated in relation to the stationary sleeves 62, 63. The desired relative position of the camshafts 5 end 6 and the co-ordinated sleeves 62, 65 may be well controlled e. g. by using the measuring element 70.

Hereupon the sleeves 62, 63 are fixed en the camshafts 5 and 6, respectively, the special .rench 64 or any other

retaining means are released from the orienting notches of the sleeves 62, 63 and after the engagement of the gear 65 with the gear 66 the operational state is re¬ stored. By using suitable accessories, the cutter-holder according to the invention may be rendered suitable for the pro¬ cessing of recurring surface-elements having been machined onto other bodies of rotation. Such surfaces are e. g. the shafts and discs provided v/ith ribs of different profiles, relieved surfaces, furtheron surfaces having been processed by milling and boring.

In figure 11 a solution has been proposed for process¬ ing shafts and discs provided v/ith ribs of different profiles. The bridles having been used for turning the polygonal surfaces are disassembled from the camshafts 5, 6. In the central bore of the camshaft 5 centering cone or cylinder is formed, into which - among others - tools 72 for processing with fly cutters may be insert¬ ed. In dependence of the profile of the fly cutters 73, 74 serrated shafts and discs, as well as ribbed shafts v/ith optional ribs may be manufactured. The spatial adjustment of the camshaft 5 needed for these processes is obtained by means of the underlay 75. In this case the telescopic cardan shaft 20 is drivin ^' the shaft 76 of the underlay, from here the driving force arrives via the bevel gear system 77 and the coupling 78 to the camshaft 6 of the cutter-holder according to the invention.

The solution to be seen in figure 11 may be well used for smaller cutter-holders according to the invention, in particular for processing ribbed surfaces, "."/hen large-sized cutter-holders are used for processing polygonal surfaces, it seems to be expedient to mount the supplementary ^' components onto the cutter-holders.

The top-view of such a solution is to be seen in figure 2.

The bridles - being indispensable for polygon-turning - are disassembled from the camshafts 5, 6 of the cutter- holder according to the invention, v/hile the complemen¬ tary unit 79 is mounted on the frontal sur ace of the casing 19. The shaft 80 of the complementary unit 79 is fixed into the centering cone 71 or cylinder of the camshaft 5. The shaft SO is driving via the bevel gear system 81 and the spur gearing 82 the small vertical main spindle vith the shaft 83; the process¬ ing tools with the fly-cutters are fixed in the center¬ ing cone of said main spindle.

Pigure 13 is shov/ing the top-viev/ of the cutter-holder according to the invention being suitable for turning polygonal surfaces, having been provided v/ith the supplementary components for backlng-off. In this case too the bridles are disassembled from the cutter- holder. The shaft of the control cam 84 is fixed into the centering cone 71 of the camshaft 5.

The roller 85 is bearing up against the control cam 84, the sha-ft of the roller is fixed into the lightweight little slide 86 actuating the cutter 4; the roller 85 is pressed by the spring 87 on the surface of the control cam 84. The slide 86 is led in the casing of the supplementary component 88 having been clamped on the casing 19. By means of this solution repeated surfaces with various profiles may be turned - in dependence of the profile of the control cam - onto the work pieces.

The scheme of the expedient drive of the cutter-holder

according to the invention and the complementary cim- ponents are to be seen in figure 14. The electromotor 89 is driving the shaft 91 via the driving unit 90, hereafter the drive is branched-off. Through the drive 92 the main spindle 93, through the epicyclic gear 94 and the rear feed shaft 95 the cutter-holder according to the invention are driven. The main spindle 93 is driving the feed shaft 98 or the lead screw 99 through the unit 97, which is branching-off the motion. Prom the shaft following the feed drive 96 drive is given to the epicyclic gear 94 via the driving unit 100.

The drive 90 is serving for the adjustment of the number of oscillation of the cutter-holder. The ratios of the numbers of revolutions according to the polygon- numbers between the cutter-holder and the main spindle may be adjusted by means of the drive 92, simultaneously, when performing normal turning processes, said drive is forming expediently a part of the main drive.

In case, if the cutter-holder is mounted onto an . already existing machine, the drive 92 may be arranged outside the main drive, before the epicyclic gear 94. The epicyclic gear 94 and the drive 100 are needed only for processing surfaces of the shape of a helical polygon or ribbed surfaces or in course of backing-off. With all such surfaces the supplementary motion depending on the feed may be transferred onto the drive of the cutter-holder. If we do not v/ish to produce work pieces of a helical shape, the epicyclic gear 94 and the drive 100 become superfluous. The main advantages of the cutter-holder according to the invention are, as follows:

On the surface of a work piece of any size and weight polygonal surfaces in an optional number and shape

' - ^OMPI

can be formed without the occurence of detrimental dynamic forces or moments. Processing may be perform¬ ed with a high accuracy. The forcing means are reliable bearings. In course of operation practically slides cannot be observed, accordingly considerable v/ear does not occur on either par _t t of the cutter-holder, that means, that even after a long operational period accuracy remains unaltered. Changing over from the processing of one type of polygonal surface to the processing of polygonal surfaces of a different size and shape is taking place quickly and without difficulty, eccentricities may be adjusted automatically and within a short time.

By using the suitable complementary components, the cutter-holder is suitable for producing ribbed surfaces vith diverse profiles, for backing-off, boring or milling.

The processing of polygonal surfaces under productive ideal cutting conditions becomes possible, as a consequence, the possibility is given to apply the polygonal sur¬ faces - being utmost advantageous from the point of view of technics - in a wide circle.

The invention, however, is not restricted to the components, i. e. embodiments having been described here; when replaced v/ith components of different format¬ ion, the scope of the invention remains unaltered.