US2773298A - Vertically adjustable turrets for machine tools - Google Patents

Description

Dec. 11, 1956 H. R. BRUET 2,773,298

VERTICALLY ADJUSTABLE TURRETS FOR MACHINE TOOLS Filed March 1, 1955 4 Sheets-Sheet 1 A 52 5, 62 K i llYVf/VTOR ATTORNEYS Dec. 11, 1956 H. R. BRUET 2,773,293

VERTICALLY ADJUSTABLE TURRETS FOR MACHINE TOOLS FiledxMarch 1, 1955 4 Sheets-Sheet 2 INVEN TOR 5 M WM ATTORNEYS 55 HINRJ RENE BRUET Dec. 11, 1956 H. R. BRUET 2,773,29a

VERTICALLY ADJUSTABLE TURRETS FOR MACHINE TOOLS Filed March 1, 1955 4 Sheebs-Sheet s INVENTOR Hf/VR/ Ravi BRl/[T B7 MQM ATTORNEYS Dec. 11, 1956 H. R. BRUET 2,773,298

VERTICALLY ADJUSTABLE TURRETS FOR MACHINE TOOLS Filed March 1,, 1955 4 Sheets-Sheet 4 J9--- 3 by 4 /5 312 I5 27 25 I i 35 H I I I y HENRI RENE BRUET y M MM ATTORNE Y8 VERTICALLY ADJUSTABLE TURRETS FOR MACHINE TOOLS Henri Ren Bruet, Paris, France, assignor to Societe Anonyme dite: Etablissements Cazeneuve, La Plame Saint-Denis, France, a French company Application March 1, 1955, Serial No. 491,411

Claims priority, application France March 20, 1954 7 Claims. (Cl. 29-355) The present invention is directed to improvements in turrets intended for use on machine tools and more particularly on lathes, so as to allow, in addition to the conventional angular adjustments, a vertical adjustment of each of the tools or pieces of work which may when required be secured to said turret.

It is a well known fact that almost all the turrets used in machine tools require a vertical adjustment of the tools or pieces of work to be secured to said turret, said adjustment being provided by the insertion of one or more, generally several, superposed shims between said tools or pieces of work and the carrier surface on the actual turret. Said adjustment is in most cases only approximate as it requires using shims of the desired thickness so as to obtain an adjustment which is sufliciently near that which is desired. It is furthermore essential for said shims to have parallel surfaces, which cannot always be the case, with a view to obtaining a steady and accurate seating of the tools or pieces of work being used and it is well known that this manner of operating is a mere make-shift arrangement which i an insuflicient and lengthy, generally costly unsatisfactory procedure often lacking stability and accuracy.

It has also been proposed to design turrets provided with carriages to which the tools or pieces of work are secured with said carriages sliding vertically along the sides of the turret. This arrangement provides more accuracy as to vertical adjustment but it is intricate, costly and does not show the desired resistance and rigidity. It also leads to substantial overhanging locations which cannot be allowed since they reduce the accuracy and are detrimental to the grade and speed of operation and prevent reaching the full efiiciency which should be readily obtainable in modern machine tools.

It has also been proposed to incorporate into ordinary turrets with a view to providing for the vertical adjustment considered, certain auxiliaries which are generally of a reduced resistance, the regulation of which is difiicult and sometimes unstable and which leads to insufiicient results.

My invention solves completely this problem of vertical adjustment and it eliminates all of the drawbacks of the aforementioned arrangements.

My invention has for its object a turret which allows a very accurate and speedy vertical adjustment of each tool or piece of work carried by it, together with a reduction to a minimum of the overhanging of the parts, the maintenance of a perfectly stable carrier surface and a rigid fixation of such tools or pieces of work as provided by the design of the components forming the turret, which latter may be locked without any play both vertically and angularly.

My invention consists chiefly in mounting on an upright fixedly connected to the stationary support of the turret and with a minimum amount of clearance, a socket of substantial wall thickness adapted to slide longitudinally over said upright, and the sliding movement of which is limited if desired by a key or by a stud while its United States Patent downwardly directed end is machined so as to'have a frustoconical shape of suitable angular size bearing on the outer end of at least one and preferably three centering bridges cut slantwise along a corresponding angle, which centering bridges may slide perpendicularly to the vertical axis of the stationary turret support with a minimum clearance in the cooperating slideways which are machined radially in corresponding numbers in the lower part of the stationary support. The sliding socket is elastic at its lower end by reason of the provision of three longitudinal slots of a suitable length therein while the upper end of said socket is cut off over the major part of its periphery so as to leave a bearing step of a sufficient height adapted to be engaged, during operation in succession and one at a time, by vertical adjusting screws or the like which are screwed, at levels which vary with the location of the edge of the tools or of the pieces of work, into the angularly adjustable body of the turret. Each screw bearing on the step constrains the socket and consequently its frustoconical lower end to assume various positions which define the positions of the centering bridges which slide along their radial slideways and serve through their other ends, which are also cut slantwise at a suitable angle, as bearings for the inner cone of a corresponding angle which is cut in the angularly shiftable body of the turret, which latter is thus held fast and clamped at difierent heights which are defined by the different positions selected for the adjusting screws in accordance with the positions of the edges of the tools or pieces of work secured to the turret.

My invention consists furthermore in providing at the upper end of the upright on the stationary support a conical member which is slotted longitudinally to form preferably three sections, said conical member being slidingly carried without any play by said upright and being urged by a suitable spring inside a corresponding cone machined in a member rigid with the angularly adjustable body of the turret. Said cone is positioned in the upper end of the upright so that the vertical adjusting screws may bear on points located between the last mentioned cone and the cones provided at the lower end of the stationary support and of the angularly shiftable body.

My invention provides furthermore means including suitable guiding and raising devices adapted to shift vertically the angularly adjustable body to bring it to a high constant level which is sufiicient to allow the free rotation of said angularly adjustable body in its uppermost position and also the screwing and unscrewing of the vertical adjustable screws with reference to their operative position, said screws being no longer stressed so that they may be operated without any effort.

According to my invention, the heads of the vertical adjusting screws are provided with a sufficient number of notches inside which a stud may be held under the action of a spring, which stud restrains its corresponding screw at the selected position while said notches have their inner apex in register with a mark provided at the desired position on the body of the angularly adjustable turret or on a part rigid with said body.

My invention covers also other auxiliary arrangements associated with the preceding features and which will be disclosed in detail hereinafter.

My invention will be readily understood from the reading of the following description, reference being made to the accompanying drawings illustrating by way of example a preferred embodiment of said invention. In said drawings, showing the invention as applied to a lathe provided with a four-tool turret:

Fig. 1 is a longitudinal cross-section through the axis of the turret in its position corresponding to the clamping of the angul-arly adjustable body in its uppermost location.

ing bridges of said turret.

Fig. 3 is a lateral cross-section of said turret at the level of the recesses providing a passage to the adjusting screws.

Fig. 4 is a lateral cross-section through the guiding and preliminary positioning members.

Fig. is a view similar to Fig. l but showing the turret in its upper released position.

Fig. 6 is a longitudinal cross-section of the turret with the elements thereof as arranged for a positioning of the angularly adjustable body at an intermediate level.

In the example illustrated, in Figs. 1 to 4, there is mounted on a member forming part of the lathe a stationary turret support 2 fixedly connected to an upright 3 over which may slide with a minimum clearance a socket 4 guided by a stud 5 which limits also its sliding movement. Said socket 4 is machined at its lower end so as to form a frustoconical surface 6 directed downwardly towards the axis of the socket and the angle of which with a horizontal plane is equal to say 45. Said socket is urged upwardly, into its uppermost position defined by abutment against the stud 5 of a transverse surface of the socket, by a coil spring 7 coaxial with the upright 3. Slots such as 8, the number of which is preferably equal to three, and which are equally distributed round the axis of the socket, and have a suitable length, provide for the elasticity of the lower end of the socket 4 while the upper end of the latter is out 01f along the major part of its periphery over a sufficient height while leaving over less than one quarter of said periphery an uncut upwardly projecting section 10 which is engaged by screws such as 9 screwed into the angularly adjustable body 11 of the turret. Said body 11 is guided with a suitable clearance at its upper end over the upright 3 and at its lower end over the outer periphery 18 of the stationary support 2. Said angularly adjustable body 11 is provided with four carrier surfaces 12 on which may be clamped, as known per se, tools such as 14 which are clamped by the screws 15 while at the lower end of this angularly adjustable body 11 .is formed a downwardly flaring frustoconical recess 16 the apex angle of which is equal to 45 with reference to a horizontal plane and which opens into a cylindrical bore 17 of body 11 slidingly mounted over the outer periphery 18 of the stationary support 2 and inside which is further provided a fluid tight packing ring 19 or the like.

In the above-mentioned outer periphery 18 of the stationary support 2 there are provided open radial slideways 20 (Fig. 2) the number of which is preferably equal to three and inside which may slide the corresponding centering bridges 21 the inner ends of which are cut slantwise at an angle corresponding to that of the outer frustoconical surface of the socket 4 against which said centering bridges are urged by springs 24 housed inside grooves 23 formed by a milling of the stationary support 2. Said springs 24 act on studs 22 fitted in the centering bridges 21 whose outer ends are also bevelled at an angle of 45 so as to be capable of engaging the inner cone 16 formed in the angularly adjustable body 11. 7

Over the angularly adjustable or shiftable body 11 is centrally secured by screws or the like means, a threaded member 25, provided with an outer thread at 26 and with an inner frustoconical surface at 27 and inside which are out four radial recesses 28 (Fig. 3) the height of which is sufiicient for the housing of the heads 29 of the four screws 9 with a view to allowing their screwing and unscrewing. Inside the threaded member are furthermore provided two or four teeth 31 which are uniformly distributed in a transverse erosswsection of the threaded member and which engage with a suitable clearance corresponding grooves 32 formed, by milling at points distributed at 90 with reference to one another, in the bearing collar 36 provided at the upper end of the upright 3. An'annular member '33 having a frustoconical outer surface the slope of whichis the same as that of the inner frustoconical re- :cess 27 in the threaded member 25, is previously bored to the diameter D of the upright 3 and is then slotted so as to form three equal sections urged against the upright 3 by an annulus 34 (Fig. l) engaging an outer peripheral groove in the annular member. A coil spring 35 engages the underside of the annular bearing to urge it against bearing collar 36 which limits its travel. In the upright 3 is formed a radial opening 37 inside which slides a stud 39 submitted to the pressure of the stressed spring 38 with said stud 39 engaging one of the preliminary positioning grooves 40 of which four are provided at equal distances from one another inside the threaded member 25 and angularly spaced by for instance with reference to the above-mentioned grooves 32 and teeth 31. Two washers ii and 44 are guided over the upright 3 and are held in position by a nut 45 which is screwed over the threads 46 cut in the upper end of the upright 3. These washers 41 and44 are spaced apart and there is centrally held therebetween with slight friction, a washer 43 to which is also secured a nut 48 which is held in position on said washer by screws 47 with said nut 48 being screwed over the thread 26 of the threaded member 25. Said screws 47 also hold on the washer 43 a cap 49 including a strap section 50 carrying a transverse spindle 51 to which the control lever 52 terminating with a handle 53 is pivotally secured.

in the head 29 of each of the screws 9 are cut at a suitable height longitudinal notches 54 adapted to be engaged by the end of a stud 56 submitted to the action of a spring (Fig. 3) sliding inside an opening 67 formed in the threaded member 25 and opening inside the recesses 28 thereof. Before the forming of said notches 54 by cutting or knurling, there are drawn round the head of the screws 9 fine annular grooves 66 (Fig. 5) spaced with reference to one another by say 1 mm. and there is engraved in the upper surface of the angularly adjustable body 11 and in register with the apex of a notch 54 in each screw, a readily visible mark 68.

Along orthogonal diametrical lines of the angularly adjustable body 11., there are provided along the same diameter and with a spacing of 90 with reference to one another, four vertical positioning pusher members 57 (Fig. 1) adapted, during the downward movement of the angularly adjustable body 11 which has been previously set in the desired angular position through a suitable angular positioning of the stud 39 and of the teeth 31, to cooperate selectively with a projection 58 extending upwardly from the stationary body 2 of the turret. The engagement between the projection 58 and one of the pusher members 57, holds the angularly adjustable body 11 against rotation with reference to the stationary support 2 while any similar arrangement of a suitable or known type may be associated with my improved arrangement with a view to obtaining the same result.

A cylindrical cover 59 provided with an opening 60 is adapted to turn around the threaded member 25 so as to uncover or to close as desired the recesses 28 and to allow for one position of the cover access to the screws 9 when the corresponding recess is uncovered, while shavings or the like objectionable material is prevented for the second position of said cover from entering the mechanism when said recesses are closed.

The operation of the turret is as follows:

When in the position illustrated in Fig. l, the vertical adjusting screw 9 is screwed home so that the lower end of the head 29 may bear against the bottom 62 of its recess 28. Said screw urges the socket 4 down against the spring 7 into engagement with the peripheral surface of the stationary support 2 while leaving a clearance j therebetween. The centering bridges 21 are thus shifted outwardly their maximum distance and the frustoconical section 16 of the angularly adjustable body 11 is engaged by said bridges so that said body is locked and held in its uppermost position through operation of the control lever 52 which, when returned to the position illustrated in dot-and-dash lines, is adapted to produce during its rotation in a clockwise direction a corresponding rota tion of the nut 48 through the agency of the cap 49 rigid with said nut, the threads 26 on said nut 48 having a. left hand pitch so as to drive downwardly the threaded member 25 which is held angularly by the teeth 31 on its inner surface and by the stud 39. This locks the frustocconical section 16 of the angularly adjustable body 11, which is fixedly connected to said threaded member, over the centering bridges 21 which are thus firmly clamped between said frustoconical section 16 ond the cooperating frustocone 6 on the socket 4. The elasticity of said socket provides for its proper bearing over the upright 3 and provides thus for the centering without any play of the lower part of the angularly adjustable body 11 whose upper end is centered also without any play by the annular frustoconical ring 33 mounted on the upper end of said upright 3. During this movement, the pusher member 57 cooperates with the projection 58 and after a suflicient clamping through operation of the control lever 52, the angularly adjustable body 11 carrying the tools is locked at the desired level by a screw 9, while it is also locked against angular movement by the pusher member 57 and the cooperating projection 58 which are brought into the desired position by the teeth 31 and the stud 39 providing for the preliminary positioning of the body 11. One of the four tools is thus held in its correct operative position. When it is desired to insert a further tool, the control lever 52 should be rocked anti-clockwise so as to move upwardly the angularly adjustable body 11 through the action of the nut 48 inside which the threaded member 25 is screwed until its transverse surface 63 (Fig. 5) engages the cooperating surface 64 of said nut 48 at which position of the threaded member 25, the teeth 31 have moved upwardly above the grooves 32 and are released with referencce to the bearing collar 36. The ring 33 including three frustoconical sections as described abuts under the action of the spring 35, against the bearing collar 36 and disengages from the cone 27. The frustoconical section 16 of the angularly adjustable body 11 has now risen away from the centering bridges 21, the socket 4 urged by the spring 7 slides upwardly over the upright 3 and engages the stud 5, and the screw 9 which is screwed into the angularly adjustable body 11 moves away from the cooperating upstanding step of the socket 4. The centering bridges 21 are also urged by the springs 24 against the frustoconical section 6 of the socket 4 and the pusher member 57 is now released with reference to the projection 58 so that the whole arrangement assumes the released position illustrated in Fig. 5.

The nut 48 and the threaded members 25-26 form thus a unit which may freely revolve anti-clockwise and urge back, by reason of the obliquety of the wall of the preliminary positioning grooves 40, the stud 39 which, as the rotary movement continues, enters a further groove 40 corresponding to the next selected tool.

It is apparent from the preceding disclosure that by reason of the threaded member 25 engaging the nut 48 to form a unit therewith and by reason of the guiding means, formed by the stud 39 acting positively in a single direction and of the teeth 31 providing positive guiding, being disengaged when in their upper position, I obtain an automatic control for the angular setting of the turret with a view to positioning in succession the different tools in their operative positions.

This being executed, it is sufiicient to act on the control lever 52 in the opposite direction, i. e. clockwise so as to keep the stud 39 in contacting engagement through its right hand wall with the corresponding part of the groove 40, whereby said stud will hold against rotation the threaded members 2526 which are now urged downwardly and reengages thus teeth 31 in the grooves 32 and frustoconical surface 27 over the three sections of the frustoconical ring 33 while carrying along therewith the angularly adjustable body 11 and the screws 9 of which one is suitably adjusted and engages the upstanding step 10 on the socket 4 so as to make the latter urge the centering bridges 21 towards the frustocone 16 on the angularly adjustable body 11. Said body which also moves downwardly advances towards said centering bridges 21 and a pusher member 57 engages the cooperating projection 58 so that, after 'a suitable clamping, the turret is locked vertically and angularly in the position illustrated in Fig. 6, similar to that illustrated in Fig. l with the sole ditference that the edge of the selected tool is adjusted vertically in accordance with the modified position assumed by a screw such as 9.

The location of the edge of each of the tools such as 14 is thus defined by a suitable adjustment of a corresponding screw 9.

The adjustment of the screws such as 9 is performed as follows:

The four tools such as 14 being clamped in the conventional manner over the carrier surfaces 12 by the screws 15, the four screws 9 are released so as to recede slightly with reference to the surface 65 on the angularly adjustable body 11, which surface 65 is then brought through a shifting thereof by the total height H pro vided for maximum adjustment, into contacting engagement with the upstanding step 10 on the socket 4 so as to obtain the lowermost adjusted position, whereas Fig. 1 shows the uppermost adjusted position. In this lowermost position, the difference in height between the edge of the tools and their accurate working height is ascertained. Said height being thus ascertained, the screws 9 are screwed down in succession until they engage the upstanding step 10 on the socket and, after the turret has been released and occupies the position illustrated in Fig. 5, each screw 9 is screwed down by a further amount equal to the difference in height which has been ascertained for the particular screw which may be obtained accurately by referring to the lines 66 drawn with spacings by one millimeter between'them and to the notches 54 the number of which may be equal, say to thirty so as to ensure for a pitch of 1.5 mm. a vertical progression by 5 hundredths of a millimeter per notch into an approximate positioning, with an allowance of 2.5 hundredths of a millimeter at a maximum to either side of the positions to be occupied by the tools. The lines 66 indicate the heights in millimeters while the apices of the notches define the hundredths through their angular distances from the mark 68. The screws 9 are arrested in the position thus defined by the studs 56 submitted to the pressure of the springs 55, the tensioning of which is suitably selected so as to permit rotating the screw heads 29 by the end of a finger for instance.

The turret may be arranged so as to ensure a maximum amount of adjustment for the height H, but it is also possible to associate with the turret at least one perfectly machined shim having a thickness H-h, It being of a magnitude of a few tenths of a millimeter, whereby this single shim allows a substantial duplication of the range of vertical adjustment under excellent conditions of stability.

The different positions of the angularly adjustable body 11 with reference to a given horizontal plane lead to the obtention of different clamping positions and consequently to various angular positions for the lever controlling the turret. In order to cut out the hindrance which may be produced by such different positions of the lever, there is provided according to my invention and as already mentioned, a strap 50 rigid with the cap 49 and carrying a spindle 51 for the pivotal mounting of the lever 52 carrying a handle 53, said lever 52 being thus adapted to be collapsed over the strap as illustrated in Fig. 1, and to remain inside a circle the diameter of which is hardly larger than the head 2 of the turret.

On the other hand, by reason of this arrangement, the operative radius of the control lever may be given any desired size without leading to any inconvenience.

The centering bridges 21 are preferably ground and trued outwardly along the peripheral line matching the smaller diameter of the frustoconical surface 16 on the angularly adjustable body 11 and inwardly along the peripheral line matching the larger diameter of the frustocone ti on the socket 4. Thus, during operation, said centering bridges may always engage the frustocones 6 and 16 along generating lines belonging to enveloping cones which are as near as possible to each other.

My invention may incorporate any desired auxiliary additions or modifications similar to or different from the features disclosed. In particular, it should not be construed as limited to those applications disclosed by way of exemplification nor to those embodiments of its various parts which have been more particularly described and it covers all the modifications thereof falling within the scope of accompanying claims.

What I claim is:

l. A rotary turret for machine tools, comprising a stationary base, an upright fixedly connected to said base, a socket slidingly mounted on said upright and having the lower end thereof provided with a frusto-conical surface, an angularly adjustable body coaxial with said socket and having the lower end thereof provided with a frusto-conical surface the angle of which is equal to that of the first-mentioned frusto-conical surface and facing the opposite direction with reference to the axis of said upright, radially sliding members having their opposite ends bevelled for engaging the frusto-conical ends of said socket and of said angularly adjustable body respectively, means for adjusting the axial longitudinal location of said angularly adjustable body with reference to said socket and means engaging said upright for locking said socket and said angularly adjustable body.

2. A rotary turret for machine tools, comprising a stationary base, an upright fixedly connected to said base, a socket slidingly mounted on said upright and having the lower end thereof provided with a frusto-conical surface, an angularly adjustable body coaxial with said socket and having the lower end thereof provided with a frusto-conical surface the angle of which is equal to that of said first-mentioned frusto-conical surface and facing the opposite direction with referenceto the axis of said upright, radially sliding members having their opposite ends bevelled for engaging the frusto-conical ends of said socket and of said angularly adjustable body respectively, vertical adjusting screws, adjustably mounted in said angularly adjustable body and adapted for engaging a section of said socket and means engaging said upright for locking said socket and said angularly adjustable body.

3. A rotary turret for machine tools, comprising a stationary base, an upright fixedly connected to said base, a socket slidingly mounted on said upright and having the lower end thereof provided with a frusto-conical surface, an angularly adjustable body coaxial with said socket and having the lower end thereof provided with a frusto-conical surface the angle of which is equal to that of said first-mentioned frusto-conical surface and facing the opposite direction with reference to the axis of said upright, radially sliding members having their opposite ends bevelled for engaging the frusto-conical ends of said socket and of said angularly adjustable body respectively, A

means for adjusting the axial longitudinal, location of said angularly adjustable. body, a frusto conical member centrally mounted on the upper end of said upright, a member fixedly mounted on said angularly adjustable body, a cone provided inside said member and means tending to move said frusto-conical member into said cone.

4. A rotary turret for machine tools, comprising a stationary base, an upright fixedly connected to said base, a socket slidingly mounted on said upright and having the lower end thereof provided with a frusto-conical surface,

an angularly adjustable body coaxial with said socket and having the lower end thereof provided with a frustoconical surface the angle of which is equal to that of said first-mentioned frusto-conical surface and facing the opposite direction with reference to the axis of said upright, radially sliding members having their opposite ends bevelled for engaging the frusto-conical ends of said socket and-of said angularly adjustable body respectively, means for adjusting the axial longitudinal location of said angularly adjustable body, a frusto-conical member centrally mounted on the upper end of said upright, a member fixedly mounted on said angularly adjustable body, a cone provided inside said memberand means tending to move said frusto-conical member into said cone, elastic means tending to move said socket away from said stationary support, and a stud for limiting the vertical sliding of said socket.

5. A rotary turret for machine tools, comprising a stationary base, an upright fixedly connected to said base, a socket slidingly mounted on said upright and having the lower end thereof provided with a frusto-conical surface, an angularly adjustable body coaxial with said socket and having the lower end thereof provided with a frusto-conical surface the angle of which is equal to that of said first-mentioned frusto-conical surface andfacing the opposite direction with reference to the axis of said upright, radially sliding members having their opposite ends bevelled for engaging the frusto-conical ends of said socket and of said angularly adjustable body respectively, vertical adjusting screws adjustably mounted in said angularly adjustable body and adapted for engaging a section of said socket, a ratchet wheel guide and a positively receding guide adapted to cooperate with said adjustable body during its displacements and allowing its free rotation when in its uppermost position, and means engaging said upright for locking said socket and said angularly adjustable body.

6. A rotary turret according to claim 3, in which said member fixedly connected to said angularly adjustable body is outwardly threaded, a nut is in threaded engagement with said member threads and is held against longitudinal sliding, a control lever is connected to said nut for rotating said nut relative to said member threads.

7. A rotary turret according toclaim 3, in which the heads of the vertical adjusting screws are provided with longitudinal peripheral notches the number of which is sufficient for them to form in association with the pitch of said screws a Vernier which permits defining the vertical axial movement of each screw with an accuracy of the magnitude of a few hundredths of a millimeter and means are provided for braking said heads at desired positions.

No references cited.

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