Патент USA US2122184код для вставки
June 28, 1938. A. scRNENE? ’ GMNDING MACHINE v2,122,184 f Y Filed Jan. l5, 1937 alzarsi ' Patented June 28, 1938 ,d narran srares ‘PATENT ermee Application January 15, 1937, Serial No. 120,708 In Great Britain February 14, 1936 3 @Balma (Cl. 51-103i This 'invention `is for improvements in con nection with g'rinding machines of the kind in which the work-piece is supported between cen tresand is mechanically rotated in pressure con 5 tact with a rotating grinding wheel. The object is to provide, in a grinding ma chine of this kind, a means of generating screw threads or other helical surfaces of a high de gree of accuracy and finish, or of correcting such surfaces after generation by a less accurate method or after a hardening or like operation, and of therebyÍ facilitating the continuous out put necessary in the repetition grinding of screw threaded bolts, studs, and the like. According to the present invention, in a grind 15 ing machine of the kind referred to, the centred ' work-piece is correctly aligned in relation to an nular serrations cn the grinding wheel by means of .a universally adjustable control finger which contacts with the helical surface either of the‘work-piece or‘of a master former rotatable be ' tween centres in axial alignment with the work piece centres, said control finger. serving also- to traverse the rotating work-piece across the face 25 of the grinding wheel at a rate governed by the speed of rotation of the work-piece and by the pitch of said helical surface. In order that the inventionV may be clearly understood and readily carried into practice, 30 reference may be had to the appended explan atory drawing, in which: ` Y Figure l is a front elevation, and Figure 2 is a plan, of such parts of a grinding machine as are necessary to illustrate the invention. Figure 3 is asimilar plan illustrating a modi 35 fied form of the invention. - Figure a is an end elevation of a detail herein after referred to. Similar letters refer to similar parts through 40 out the several views. ’ direction of the axis of the work-piece a. At right angles to the slide table f is arranged an other slide carrying the rotatable grinding wheel î, which therefore is capable of move ment at right angles to the axis of the work piece a, this movement determining the-size of the work-piece a diametrically. The face of the grinding wheel i is formed with annular serra ti'ons disposed >at right angles to the axis of the work-piece av and adapted to produce the desired form upon the work-piece a, which is rotated _by a backing wheel y' mounted either on a pivoted arm or on a slide so that it can be spring-loaded or otherwise urged towards the work-piece a so as to drive it by frictional contact. The backing Wheel y’ is geared to an electric motor or other source of power so as tovbe driven at a speed which imparts a suitable peripheral ve locity to the work-piece a. Attached to the Agrinding wheel head is an arm k carrying a con 20. trol ?inger l which abuts radially on the top of therwork-piece a„ this iinger l being spring loaded and being universally adjustable in rela tion to the ,work-piece a, that is to say, it has a fine micrometer adjustment in directions par 25 allel to the axis of the grinding wheel i, and is also adjustable in two planes at right angles to the grinding wheel axis to suit various diameters of work-piece and grinding wheel, the con trol finger l being also rotationaily adjustable in its bearing. ì In the operation of this form of the machine, the grinding wheel Ai is first withdrawn either manually or automatically, taking with it the control finger l. The work-piece a is then in 35 serted between the centres b, and the backing wheel 9’ is brought into contact-so as to rotate the work-piece. The grinding wheel i> is then brought upto the work, the control finger l con jtacting with the work-piece a and aligning it 40 In a convenient method of carrying the iin-> with the serrations on the wheel í, which is now vention into effect,V as illustrated in ië‘lgures` 1 in its grinding Iposition. ^ It will be seen that and 2 and as applied by way of example to a the eiîect of the control ilnger l engaging with grinding machine of the kind referred to for the initially formed screw-thread on the rotat 45 the correction of screw-threads initially formed ing work-piece a is to cause the slide f which yit uponÍ bolts, studs, and the like by a rolling or other carries the work-piece to travel across the face operation, the work-piece a is mounted between of the grinding _wheel i for the grinding opera a pair of centres b of which one is adjustable tion, at a rate governed by the Yspeed of rotation` of the work-piece a and by the pitch or the as at c for varying lengths of work and is spring thread thereon.l Pieces having a threaded length loaded as at d so as to support the work-piece a 50 but leave it free to rotate, the centres being not exceeding the width of the grinding wheel i will be completed in a little more than one revo mounted in anti-friction bearings. The head stocks e _carrying the centres b are mounted on lution, whilst any longer piece will revolve until a table î which slides freely on anti-friction the whole of its threaded surface has passed the wheel i or the control ñnger i. 55 bearings g on the bed h of the machine in the 2. 2,129,184 As an alternative to the adjustable mounting t of the grinding wheel i, the grinding wheel head I claim: In a grinding machine of the kind described. may be stationary, and the whole of the ,other - for1. the correction of screw-threads and other mechanism be arranged to slide in a direction at helical surfaces, the combination of an annularly right angles to the axis of the work-piece a. serrated grinding wheel, a pair of centres adapted Moreover the complete slide unit may be dupli to support the work-piece, a. backing wheel -cated so vas to provide a series of loading and operating stations, the work being loaded at one station whilst it is operated on at another, and 10 the change of stations being eii’ected either manually or automatically. In another method of carrying the invention into eñ’ect, as illustrated in Figure 3 and as ap plied by way of example to a grinding machine 15 of the kind referred to for the generation and finishing of screw-threads upon bolts, studs, and the like, the work-piece blank a is mounted be tween one pair of centres b, and a master former m is similarly mounted between another pair of centres bl, the two pairs of centres b and b1 being disposed in axial alignment, and both the 'work-piece a and the former m being of the adapted to rotate the work-piece between said centres in pressure contact with the grinding wheel, and a universally adjustable control finger adapted to abut on the helical surface of the 10 work-piece, said finger ensuring that the screw threads on the centred work-piece are correctly aligned in relation to the annular serrations on the grinding wheel, and serving also to traverse therotating work-piece across the face of the 15 grinding wheel at a rate governed by the speed of rotation of the work~piece and by the pitch of the helical surface. 2. In a grinding machine of the kind described, for the generation of screw-threads and other 20 helical surfaces, the combinationof an annularly serrated grinding wheel, a pair of centres adapted same diameter. The work-piece a and the former ~to support the work-piece, a backing wheel 1p. are rotated by separate backing wheels fand j* adapted to rotate the work-piece between said which are independently urged forward to pro-- centres in pressure contact -with the grinding vide a frictional drive at the same speed both for wheel, a helically surfaced master former, a pair 26 the work-piece a and for the former m. The of centres adapted to support said master former face of the grinding wheel i is formed with an-~ 'in axial alignment with the work-piece, a backing nular serrations disposed at right angles'to the wheel adapted to rotate the master former be 30 axis of the work-piece a and adapted to produce tween said centres at the same speed as the work the desired form on the work-piece a. A uni piece, and a universally adjustable control ñnger versally adjustable control finger l as hereinbe adapted to abut on the helical surface of the fore'described is attached to the grinding wheel master former, said ñnger ensuring that the head by a carrier arm Ic so as to be adapted for centred work-piece is correctly aligned in rela engagement with the screw-thread on the master tion to the annular serrations on the grinding former m. ' In the operation of this modified form of the machine. the `machine is loaded as herelnbefore described with reference to the ñrst form of the invention, and it will be seen that as the control finger l is in engagement with the master former wheel,A and serving also to traverse the rotating 35 work-piece across the face of the grinding wheel at a rate governed by the speed of rotation of the master former, and by the pitch of the helical surface thereon. ' v 3. In a grinding machine of the kind described, m .rotating at the same speed as the work-piece ' for the generation of screw-threads and other a, this causes the workepiece a to travel across helical surfaces, the combination of an annularly _ the face of the grinding wheel i, thus generating serrated grinding wheel, a pair of centres adapted ,the desired screw-thread and thereby reproduc ,to support the> work-piece, a backing wheel ing the form of the master m on the'blank o, one adapted to rotate the work-piece between said or `more revolutions being required to complete centres in pressure contact with the grinding the piece. When-it is required to pass the work wheel, `a helically surfaced master former, a pair ìhrough the machine more than once, for example of centres' adapted to support said master former or the production of a highly accurate finish, a axial alignment with the work-piece, a backing second control finger l1 may be provided, this4 in wheel adapted to rotate the master former be ' operating in association with the screw-thread tween said centres at the same speed as the work eratedl on the work-piece a and being ad piece, a universally adjustable control finger ._ì table both in relation to the primary control - adapted to abut on the helical surface of the ¢ - er land to the 'serrations on the grinding master former. and a second control finger wheel i, so as to assist in re-positioning the work piece a on the grinding wheel i for the secondary grinding operation. ' ` It will be appreciated that work with aninter-. adapted to abut on the helical surface generated on the work-piece. the first-mentioned control linger ensuring that the centred work-piece is i correctly aligned in relation to the annular ser rupted surface can betground. provided that a rations on the grinding wheel, and serving also continuous surface is available at some part or _ to traverse the rotating work-piece across the other so that the backing wheel i can rotate the face of the grinding wheel at a rate governed by work-piece. For example, screwing taps may'be treated by arranging the backing-wheel 1 against the speed of rotation of the master former and eter of the master former m to suit. For this type of work, when a second pass is required, the by the pitch of the helical surface thereon, and the second control finger serving to facilitate the 05 correct realignment of the screw-threads gener second control finger ll may be extended laterally secondary grinding and finishing operation being the shank of the tap and by adjusting the diam as shown in Figure 4 so as to bridge the flutes cix 70 of the work-piece a and engage two lands at the same time. . . ‘ ated on the centred work-piece in the event of a required. , ° - sRTHUR scarvENER.