US3104565A

US3104565A - Metal working

Info

Publication number: US3104565A
Application number: US815153A
Authority: US
Inventors: Claus L Sporck
Original assignee: Lodge and Shipley Co
Current assignee: Lodge and Shipley Co
Priority date: 1959-05-22
Filing date: 1959-05-22
Publication date: 1963-09-24
Anticipated expiration: 1980-09-24

Description

Sept. 24, 1963 c. 1 sPoRcK 3,104,565

METAL WORKING Filed May 22, 1959 1e sheets-sheen qfwfwmfm @L Sept. 24, 1963 c.1 sPoRcK 3,104,565

METAL WORKING Filed May 22, 1959 16 Sheets-Sheet 2 Z lgVENTOR j BYMFM ATTORNEYS C. L. SPORCK METAL WORKING Sept. 24, 1963 16 sheets-sheet :s

Filed May 22, 1959 ro--o--E @ZM if. MW# ATToRNl-:Y

Sept. 24, 1963 c. 1 sPoRcK METAL WORKING Filed May 22, 1959 16 Sheets-Sheet 4 INVENTOR 92 BY /97 C: fwd i M 93 ATToRNEYs Sept. 24, 1963 c. L. QsPoRcK METAL WORKING 16 Sheets-Sheet 5 Filed May 22, 1959 cefmad ATTORNEYS Sept 24, 1963 c. L. sPoRcK 3,104,555

' METAL WORKING Filed May 22, 1959 16 Sheets-Sheet 6 INVENTOR ATTORNEYS C. L. SPORCK METAL WORKING Sept. 24, 1963 16 Sheets-Sheet 7 Filed May 22, 1959 l lall:

ATTORNEYS Sept. 24, 1963 c. L. sPoRcK 3,104,565

METAL WORKING Filed May 22, 1959 16 Sheets-Sheet 8 'fr J5 X /l' /J l L :I I

:j y INVENTOR f /1 1 a @@Mffwf I l I BY /60/ Y); [/54 ATTORNEYS sept. 24, 1963 Filed May 22, 1959 c. l.. sPoRcK 3,104,565

METAL WORKING 16 Sheets-Sheet 9 @am a@ l im 'JW/WW\\\\\\\\\ INVENTOR BY g g 1 j if ATTORNEYS Sept. 24, 1963 c. l.. sPoRcK A 3,104,555

METAL WORKING Filed May 22, 1959 16 Sheets-Sheet lO @M R Wwf/MM ATTO RNEYS C. L. SPORCK sept. 24, 1963 METAL WORKING 16 Sheets-Sheet l1 Filed May 22, 1959 Nvl-:NTOR

(lm f7/:amai BY v we# ATTORNEYS C. L. SPORCK METAL WORKING sept. 24, 1963 16 Sheets-Sheet 12 Filed May 22, 1959 @ZM R?? BY M EY\S` Sept. 24, 1963 c. 1 sPoRcK 3,104,565 v METAL WORKING Filed May 22, 1959 16 Sheets-Sheet 13V 255 I ITVENTR Wywmw ATTORNEYS Sept. 24, 1963 c. L.. sPoRcK 3,104,565

METAL woRKNG I lNvENTofR Sept. 24, 1963 C, L. sPoRcK 3,104,565

METAL WORKING 1N5 VENTO? BY HM M ATTORNEYS Sept. 24, 1963 C, SPORCK 3,104,565

METAL WORKING Filed May 22, 1959 16 Sheets-Sheet 16 5,5/ 333535 J5@ j 525 I, l 525' ATTORN EYS United States Patent O hio Filed May 22, 1959, Ser. No. 815,153 1S Claims. (Cl. Sil- 13) This invention relates to the art of metal working and in particular relates to methods and apparatus Ifor forming hollow, generally cylindricallyshaped articles from sheet metal blanks.

The invention is concerned with the making of elongated, cylindrically-shaped articles havin-g use in -a wide variety .of industrial and lmilitary applications, particularly where ihigh strength, light weight and precise dimensions are mandatory. For example, cylinders made in accordance with the invention may be used as storage and control tanks, particularly in the chemical and dood processing industry. As to military use, the articles formed by the methods of the invention are ideally suited for components of rockets and missiles such as fuel containers, skin parts, body structural members and the like.

Components such as mentioned above for rockets and missiles may have dimensions in the order of the following: length: l(}"5'(l0"; thickness: .0110-111"; diameter: 20"-150". Such components are made by the familiar wrapping and |welding techniques Where a flat blank of rolled steel is formed into cylindrical shape, welded at the abutting edges and then machined to dimensions. These techniques have several disadvantages. For example, where the component is to be of substantial length, it is necessary to Vform several like objects and then weld the adjacent ends. With such procedure it is very diicult to match diameters and to maintain all of the parts coaxial so that the wall of the part is truly symmetrical fwith respect to the axis. Complex and costly machining operations are required to maintain dimensions. Furthermore, the making of large parts by these techniques ordinarily requires heat treatment after welding or machining -which often can lead to undesirable distortions. Where high strength is desired, the thickness of the material must be disproportionately large which adds to the total weight and is Wholly undesirable in airborne devices. The outer skin of a ballistic missile should be axially true as otherwise errors may arise in the desired trajectory, and for iiuel containers ttor rockets it is imperative that the inside dimensions be accurately controlled in order that the desired rate of burning will take place. Conventional wrapping and welding techniques do not lend themselves to the obtaining of these desired characteristics.

Besides the wrapping-'weldingemachining techniques mentioned above, cylinders and tubes have been made by the use of Iroller and spindle methods lwherein a blank is supported on a spindle or a mandreland while the spindle and blank are rotating, one Vor more rollers engage the blank and with relative axial motion as between the roller and the blank, the Wall of the blank is reduced in thickness and elongated. In some instances the blank has a closed end which is held in abutting relationship with the end of the spindle and the relative axial motion of the roller with respect to the blank is in a direction away from the closed end, the reduced part of the yblank extruding along the spindle under the -action of the roller so as to completely be formed on the spindle. In other instances the b-lank is supported on the spindle and moved axially into the rollers or, conversely, the rollers are moved along the blank (with one end of the blank being held fixed); in either case the relative axial motion of the roller with respect to the blank being such that the rworking forces are taken through the unworked portion of the ,e ICC blank and the blank extrudes oli the end of the spindle. In still other instances the rollers are positively driven and also oriented with respect to the spindle -so that the blank and spindle are pulled between the rollers rfc-r the reducing operation.

These methods have not been used heretofore ttor the yforming of articles of the kind in question because o-f several basic difficulties.

Many of the above-mentioned techniques contemplate that the blank be hot rolled. While hot rolling has many desirable advantages, it has the distinct disadvantage of not producing strain hardening, and strain hardening is highly desirable in articles of the kind under consideration because of the attendant improvements in strength properties.

The most significant disadvantage, however, lies in the failure of these techniques to provide for dimensional accuracy, particularly. with regard lto Wal-l thickness and inside diameter. The processes of the kind mentioned vabc-ve, at least insofar as -I am aware, contemplate that the blank or the formed part expand -or open up after it leaves the rollers. not provide that each axial increment of the nished part have the rsame wall thickness and the same inside diameter as existed -at the ltime of its reduction. r[This has the effect of making it impossible to hold close and uniform tolerances in diameter, wall thickness and axial concentricity of the finished part. Furthermore, those processes contemplating the forming of the part completely on the spindle are .of little value for making articles of substantial length and diameter because of the practical ditliculties in making the required size spindle.

With the above in mind then, the present invent-ion contemp-lates methods and equipment for the forming of elongated, cylindrically-shaped articles by way of roller `and spindle means but which are constructed and operated to eliminate the disadvantages of Ithe spindle-roller and the wrapping and Welding techniques mentioned above and to provide tfeature-s and advantages which are not present in and indeed are impossible to obtain With such conventional techniques.

1t is one object of the invention to provide roller and spindle apparatus and methods Afor using the same lfor the production of elongated, cylindrically-shaped articles having extremely high dimensional accuracy, both as Ito Wall thickness and inside and outside diameter and axial concentricity.

Another object of the invention is to provide roller and spindle apparatus and methods of using the same for the production of elongated, generally cylindricallyshaped articles having extremely high strength properties yas compared to fthose of the initial starting blank and which have la very high degree 'of dimensional accuracy.

Another obje-ct of the invention is to provide roller and spindle apparatus and methods of using the same for the production of elongated, generally cylindricaliyshaped :articles having very Vhigh strength properties yet With a minimum of Weight and a high order of dimensional accuracy.

Another objeot of the invention is toprovide roller and spindle apparatus and methods of using the same for the production oi elongated, generally cylindrically-I In other words, present processes do curacy is principally a function of extrusion rate and that extrusion rate can be desirably controlled by simultaneously reducing the discrete fractional proportions of the blank. The principal `control factors for accomplishing the foregoing are the number and extent of the fractional reductions, the initial feed rate of the blank and the rotational speed of the blank, all of these being coordinated to produ-ce the desired result 4and the exact relationship of these factors depending upon the kind of material being worked.

In' one aspect the invention contemplates the forming of elongated, cylindrically-shaped articles by simultaneously reducing and extruding discrete radial and axiallyspaced portions of the Wall of a cylindrically-shaped blank and controlling the extrusion rates so that the extrusion rate of the finally-reduced portion is such that each increment of the formed article has the same inside diameter and Wall thickness as existed at the nal reduction.

In another aspect the invention contemplates the forming of a cylindrically-shaped article by the elongation :and reduction of a blank by a roller cooperating with a spindle, the roller having a plurality lof rolling sections serially spaced along the axis of the bla-nk with each Working surface taking a fractional proportion of the total desired reduction and with the blank feed rate, the rotation speed of the blank and the number and extent of the reductions being correlated to control the extrusion rate of the final reduction.

Another aspect of the invention contemplates the forming of axially dimensioned, elongated, generally cylindrically-sliaped articles by spindle and roller means, the roller comprising a plurality of rolling sections simultaneously operating on the blank to reduce discrete portions iand move the same at different extrusion nates so that the linal extrusion rate is such that the formed blank has a uniform wall thickness the same as the spacing between the spindle salnface and the final roller and a uniform inside diameter which is the same as the outside diameter of the spindle.

In another aspect the invention contemplates the forming of accurately dimensioned, elongated, cylin-dricallyshaped articles lby Way of a spindle and roller means having a plurality of rolling sections which are serially spaced along the axis of the blank and each being located at a different radial distance from the axis of the blank so that each rolling section effects a fractional proportion of the total reductionI required and operates simultaneously with the other sections and determining the linal extrusion rate by controlling the spindle speed, the blank feed rate and the number of reductions.

Plibe foregoing may be obtained by several different forms of equipment but it is essential that such equipment have certain basic characteristics. On'e of the most important of these is the construction of the roller which provides for the simultaneous reduction and elongation of discrete portions tof the blank. Another is that 'the equipment must provide for the control of the blank `feed rate and the blank rotational speed and it is preferred that such control be variable in nature so that the equipment is adaptable for a Variety of different materials and blanks of varying sizes.

According to the invention, the preferred form of roller has a plurality o-f rolling sections, all of which are mounted on a common rotational axis and Vall have the same diameter and are held in closely abutting relationship with one another. Further, the invention contemplates that the roller be mounted so that it is tiltable with respect 4to the rotational axis of the blank, the several rolling sections and the tilting being coordinated so that the roller may be positioned with each of the rolling sections located at a different radial distance from the rotational axis of the spindle and serially spaced along the axis of the blank. This per-mits each of the rolling sections to perform its work on different tions of the blank.

In addition to the foregoing, the apparatus of the present invention provides a machine having a unique arrangement and construction of parts and a mode of operation all coordinated in a highly novel manner. For example, the invention contemplates that the roller means be non-movable (axially of the blank) and that the rotating spindle and blank, for the working operation, be moved directly into the roller means. This is of special advantage from the standpoint of simplifying the machine construction,

machine operation, savings in 4manufacturing and mainte-Y nance costs. This type of construction is not simply an engineering choice, so to speak, as between whether to make the rollers move or to make the spindle move, because the lelection of a design incorporating spindle movement involves the problem of how to effect spindle rotation While, at the `same time, providing for axial movenient. This problem becomes critical because itis highly desirable that the power for the movement be hydraulic, in view of the large working forces involved. Rotating hydraulic connections are highly undesirable in machines of the kind in yquestion because with the Vrather high rotational speeds involved and with high unit pressure being applied for long periods of time (to eiect complete working of the blank), there is a very great danger of leakage which is highly undesirable from the standpoint of maintaining feed blank rate, the blank feed rate being impor- Y tant for maintaining the desired extrusion irate.

The present .invention solves the foregoing problem by a unique hydraulic piston and cylinder arnangement coupled d-irect-ly to the rotating spindle and providing movenient thereof but with neither the piston nor cylinder rotating.

The invention contemplates that the roller means comprise three roller assemblies equally spaced about the rotational axis of the spindle and that the spindle axis extend vertically so that during the Working operation the rotating spindleV and blank are moved upwardly .into the v.

rollers. This arrangement fhas several advantages, for eX- ample, in permitting simplified construction for synchronizing the rollers, ie., that corresponding parts of the rollers occupy the same radial distances from the rotational axis of the blank and lie in the same transverse planes.

Furthermore, by having the rollers each located at the vertex of a triangle, there is very little, if any, unbalanced radial thrust on the spindle. tendency of the spindle to buckle and is liighly desirable from the standpoint of maintaining dimensional accuracy.

Furthermore, `the spindle has a symmetrical construction so that the center of gravity is located along its rotational axis and, therefore, there is no radial thrust on the spindle or blank due to the forces of grav-ity. Also, the piston and cylinder means are arranged so that its thrust for moving the spindle lies along the rotational axis of the spindle.

The apparatus of the invention contemplates that each of the roller assemblies be controlled by tracer mechanism for the working operation. In the making of articles of the nature discussed, it is possible to lock each of the roller assemblies in a xed radial position. However, the use of tracer mechanism arranged as disclosed herein has distinct advantages, particularly from the standpoint of controlling the dimensions of the articles being forme-d. Furthermore, in certain instances it may be desirable to form an article having a tapered wall and from this standpoint the tracer control is substantially advantageous. For

tracer control the invention contemplates that each roller assembly be mounted to accommodate relative mot-ion as' therewith, the templet being preferably interconnected with peripheral sec- This, of course, avoids anyV the piston and cylinder means so that, while being axially movable, it has no rotary motion.

While in the foregoing I have discussed in somewhat general terms the various advantages, features and objectives of the invention, it will be apparent as the description proceeds that the invention has other highly desirable advantages and features.

The preferred manner of practicing the methods of the invention and the preferred construction of a machine for practicing the same will be apparent from the following description and drawings wherein:

FIGURE l is a front elevational View illustrating the general assembly of the machine;

FIGURE 2 isa plan view of FIGURE l;

FIGURE 3 is a plan section :taken on the line 3 3 of FIGURE 1;

FIGURE 4 is `a vertical section taken on the line 4-4 -of FIGURE 2 with certain parts appearing in elevation;

FIGURE 5 is an enlarged, broken-out section of certain o-f the par-ts of FIGURE 4;

FIGURE 6 is a vertical section taken `on the line 6 6 of FIGURE 4 with certain parts omitted;

FIGURE 7 is an enlarged vertical section taken on the :line 7-7 of FIGURE 2 and also on the line 7-7 of FIGURE 8;

FIGURE 8 a plan sect-ion taken on the line 8-8 of FIGURE 7;

FIGURE 9 is an enlarged plan section taken on the line 9 9 of FIGURE 10;

FIGURE l0 is a fragmentary cross section on the line lil-16 of FIGURE 9; l

FIGURE 1l is ya perspective view of a drive bushing used in the spindle assembly;

FIGURES 12, I3 and 14 are plan, side and end views respectively ofthe roller assembly;

FIGURE is a plan section taken on the irregular line 15--15 of FIGURE 1v with certain parts omitted;

FIGURE 16 is a vertical section taken on -the line 16-16 of FIGURE 15;

FIGURES 17, 18 and 19 are side, plan `and end views respectively -of the tracer valve .mounting structure;

FIGURE 20 is a diagrammatic view illustrating the hydraulic circuits fo-r moving the roller assembly toward 'and away from the spindle axis fand for controlling the vertical motion of the spindle assembly;

FIGURE 2l is a diagrammatic view of the tracer valve;

FIGURE 22 is a schematic wiring diagram illustrating certain of the electrical circuits used for operating the machine;

FIGURE 23 is a schematic wiring diagram illustrating the controls for certain of the motors used in the machine; l

FIGURES 24, 25 and 26 are diagrammatic views illustrating the forming of a yblank into an elongated cylindrically-shaped article;

FIGURE 27 is a fragmentary view illustrating certain of the operations taking place in FIGURES 24--26 and FIGURES 28 and 29 are fragmentary views of alternative roller for-ms.

General Description As best seen in FIGURES l 'and 3, the machine M is 'supported over a pit P by the door F and the columns C and C4 in the pit. While the Imachine could be mounted so that the lowermost part thereof was suspended just above the floor level, lthe pit arrangement is preferred in order to reduce the overall height of the machine.

The rbed of the machine comprises a main base 1 (see FIGURE 3) which has connected thereto the

roller bases

2, 3 and 4. The roller bases are spaced approximately 120 apart from one another and respectively carry the roller rests 5, 6 and 7 which support the roller assemblies 16, 11fand 12. As best seen in FIGURE 3, the main base is apertured as indicated at 13 and within the aperture is supported the spindle or spindle assembly =14 (see FIG- URE 4) which is adapted to be rotated and moved along its -axis of rotation which, in this instance, extends vertically. The spindle assembly carries 'the lblank B. Connected with each of the

rollers

10i, 11 and 12. are

tracer valves

15, 216 and 17 which ycooperate with templets 2t), 21 and 22 for `controlling the position of the rollers with respect tothe rotational .axis of the blank or spindle. The

templets

20, 21 and 22 are mounted on templet supports 23, '24 `and 25 which are all interconnected with the spindle to Ibe moved in a vertical direction therewith in a manner which will be explained hereinafter.

The general manner in which the machine is used is explained following. The parts `are in the position as shown in FIGURES 1 and 6 and the spindle is rotated (causing rotation of the blank) and then moved vertically until such time that the rollers `engage with the blank. With continued rotation and upward motion, the rollers work the blank, causing `a reduction in the wall thickness thereof `and the -blank extrudes upwardly and away from the spindle.

The Main Base As Ibest seen in FIGURES 3 and 4, the main base 1 is a compartmented structure comprised of Ivertical cross braces 26 .and `annularly-shaped horizontal braces 30, 31 and 32. As indicated in FIGURE 3, the base is supported at three point-s over the pit; vfor example, ione corner is supported by the column C, the other corner is supportedgby the column `C-l and the other corner is supported by the floor as indicated at 29. 'The three

annular braces

30, 31 and 32 form the aperture 13 referred to heretofore. Within the aperture 13 is a spindle housing 33 which at the top rests on the brace 30 and on the side 'is supported laterally by the inwardly facing edges yof 'the

braces

30, 31 and 32. On the bott-om of the spindle housing is an annular-:shaped lower bearing housing 34 `and Aon the lower bearing housing is a piston support 35 which, as indicated in FIGURE l, extends down -into the pit P. The cross sectional shape of the piston housing will be seen from an inspe-ction of FIGURE l5. All of `the parts just described are `all rigidly tied together by convention-al bolting means to make a strong unied structure. Y

Roller Bases Each of the

roller lbases

2, 3 and 4 are substantially identical in structure and include vertically extending braces 40 as indicated in FIGURE 3 for the roller base 2. Each roller base is bolted to the main base.

The Roller Rests Each of the roller rests is identical in construction and the description will be principally in connection with the roller rest 5 as shown in FIGURES 7 'and 8. The roller rest has a main slide `411 by means of which the rest is mounted on top of the roller base 2. The roller rests are adapted to be adjustably moved toward and away from the rotational taxis A of Ithe spindle for purposes of setting up the machine for 'blanks of various diameters. For guiding this movement .and for preventing any twisting movement of the roller rest during the working operation, there are cooperating guide-ways in the Iform of abutting shoulders on the main slide of the rest and the roller base; for example, see in FIGURE 6, the shoulders 46 and `47 on the main slide of r-oller rest 7 and the shoulders 4S and 49 on the roller base 4. Similar abutting shoulders r.for the roller ibase 2 and roller rest 5 are indicated at Sti-Sil and S1-551 in `FIGURE 8.

The roller rest is adapted to I.be adjustably moved as described following. In FIGURE 7 a nut 52 is attached -to the bottom of the slide 41 and this cooperates with a screw S3 mounted in the bracket 54 secured to the base Z. The screw is mounted so that it can be rotated `but not Imoved axially. The screw may be manipulated by a wrench or the like applied to .the head 55. While it is not shown, the roller base 2 may be provided with grooves on its top surface to receive hydraulic fluid tEorced into the grooves Iby appropriate pumping apparatus. This has the eiect of lubricating or lifting the rest away from the base so that the same can be easily adjusted by means of the screw 55.

After the roller rest has been set to an adjusted position, it may be locked in adjusted position as described following. The shoulders 50 on the base carry clamp plates 60 and 61 and the shoulders S1 of the base carry clamp plates 62 and 63. These clamp plates are arranged so that when the same are tightened down they engage the shoulders S and S1 on slide 41 and exert a large `force to hold the rest against movement and particularly against backward tilting movement. To insure against outward; movement of the rest, the notches 64 and 65, cut in the plates 61 and 63, cooperate with

lock plates

66 and 70 fixed to the slide 41.

As best seen in FIGURE 2, the

turnbuckle assemblies

71, 72 and 73 are connected to and extend between the respective roller rests. The turnbuckles rigidly tie the roller rests together and are 4for preventing outward movement and tilting of the roller rests during a working operation. 'Ihe turnb'uckles are adjustable to provide for radial adjustment of the roller rests as mentioned above.

'Ihe main slide 41 has a top cover 74 and these form a central aperture in the slide as indicated at 75 in FIG- URE 7. In vertical .cross section the aperture is generally rectangular in shape as indicated for the aperture 7S of the roller rest 7 shown in FIGURE 6. Within this aperture is disposed the roller assembly.

The roller assembly 10 is slidably mounted on the roller rest to accommodate relative motion between the assembly and the rest in a direction toward or away vfrom the rotational axis of the blank, this relative motion being controlled by the tracer valve 115 and the cooperating templet 20. The manner of mounting the roller assembly for such movement will next be explained.

The sides of the slide 41 Within the aperture are provided with a pair of guideways such as the ways for the roller rest 7 indicated at 76 and 77 in FIGURE 6. Within the guideways of the slide 41 is disposed a cradle slide 78 which in plan has a U-shaped cross section as indicated in FIGURE 8. The relative motion as between the cradle slide and the Iguideways is controlled by a piston and cylinder arrangement described following. 'Fhe slide 41 and .the ltop cover 74 (FIGURE 7) carry a cylinder adapter 80 which mounts a cylinder body 81. On one end of the cylinder body there is a cylinder end cover 82 and on the other end there is an kend cover S3. 'I'hese elements form the cylinder 84 within which is disposed the piston 85. The piston 85 has a piston rod comprising an enlarged section 86 and a reduced section 87 which is attached to the cradle slide 78. Also attached to the piston is an arm 90 carrying an adjusting nut 91. The nut 91 is 'used in set-up purposes, particularly in determining the innermost position yof the roller assembly .10.

The conduits 92 and *93 are ttor the supply of ll-uid for the cylinder 84 so as to effect back and vforth movement of the piston or to permit back and dorth movement ot' the cylinder while the piston remains lixed as will be explained later.

Secured to the cradle slide 78 is a cradle 94 which is arcuate in shape and has an arcuate guideway 95, the axis of the guideway lying in a plane which contains the rotational axis of the spindle. As seen in FIGURE 8, on either side of the -guideway are two slots 96 and 97. Mounted on the cradle is a swivel 100 which is also arcuate in shape conforming to the shape of the Vcradle and has a portion '101 which extends into the lguideway 95. The swivel carries a segmental part of a worm wheel 102 which cooperates with a worm 103 mounted on the cradle. The swivel also carries a plurality of T-bolts 104, the heads of which cooperate -with the slots 96 and 97. When the TJbolts are tightened up, the swivel is held tightly on the cradle. When the lbolts are loosened, the worm 103 can be rotated by a wrench applied to the head 105 which causes the swivel to move along the cradle. The purposes of the swivel adjustment will be explained shortly.

The roller assembly 10 is mounted on the swivel and tarcuately movable therewith. The roller assembly has a housing 106 which abufts the swivel and is xed thereto 'by means of bolts such as the bolts 107 for the roller :assembly 12 as shown in FIGURE 6. The roller assembly is arranged to be adjusted in a vertical direction by means of the nut which `is xed to the swivel and' a. sscrew 111 cooperating with threads in the housing 106. The key 112 which is disposed in ways on the swivel and cradle guide this vert-ical adjustment. The vertical adjustment is for placing corresponding parts of the roller assemblies in the same horizontal planes.

Roller Assembly Each of the roller assemblies is identical in construction andthe explanation of this `will be principally in .connection with the roller assembly 10 which is shown in some detail in FIGURES 7, 12, 13 and 14.

'Ihe housing 106 of the roller assembly mounts a pair of -upper and lower bearing caps 115 and 116 which `are secured to the housing by means of the screws 1720 `(see FIGURE 12). Bearing caps 115 and 116 support the covers 121 Iand 122. Within the assembly there is a roller shaft 123 being rotatably supported by means of the

irrboard bearings

124 and 125, and outboard bearings i126 and 127,V the

bearings

124 and 125 being disposed between the shaft and the caps, and the

bearings

126 ,and 127 being disposed between the shaft and the covers.

The shaft has a shoulder 130 upon which bear the several :rolling sections-131, the sections being held rrn against the shoulder by the lock nut 132. This arrangement, to-

gether with the key 133, rigidly tie the'rolling sections` together for rotation.

In the present embodiment 'the rollin-g sections are all of lidentical construction having the same diameter and identically'conigured Work-ing tips or working surfaces. As will be apparent from FIGURE 7, the rolling sections 131 are serially spaced along ythe rotational axis A of the blank B and the working ltips are spaced at different radial Vdistances from this axis. As indicated heretofore,

ithe function of the rolling sections is to reduce fractional port-ions of the blank and, from this standpoint, may be considered as independent rollers.

'Ihe roller assembly, the swivel and the cradle areY arranged so that when `the swivel is arcuately adjusted, the

roller assembly pivots aboutthe point 135 of the work-V ing tip of the center rolling section. Since the roller assembly pivots about the point 135, it will be seen that by ldifferent arcuate adjustments, the different roller Working tips can be spaced dilerent distances from the rotational axis A. For example, .in FIGURE 7 it will be seen that all of the live working tips occupy diierentV radial distances from this axis. If the roller assembly is then adjusted, say more counter-clockwise, the top -rolling section will move closer to the axis while the bottom rolling section will move farther from the axis. The -center rolling section, of course, does not move sinceV the roller is pivoting about its working tip. This arcuate adjustment of the roller assembly, together with the radial adjustment provided by the setting of nut 91 provides for variation in the total reduction to be taken on a blank Vso that the pivoting effects equal but opposite motion of corresponding sections on opposite sides of center.

The roller assembly is preferably mounted so that the rotational axis of the shatt 123 lies in a plane containing the rotational iaxis A of the spindle. Further, the` Where an even number of v

Claims

2. IN A MACHINE TOOL: A BED INCLUDING A ROLLER BASE; A SPINDLE FOR SUPPORTING A BLANK TO BE WORKED; MEANS MOUNTING THE SPINDLE ON THE BED FOR ROTATION ABOUT A GENERALLY VERTICAL AXIS AND FOR MOVEMENT ALONG ITS ROTATIONAL AXIS; A ROLLER REST MOUNTED ON SAID BASE; TRACER TEMPLATE SUPPORT MEANS AND A TEMPLATE MOVABLY MOUNTED ON SAID BASE; MECHANISM CONNECTING SAID SUPPORT MEANS AND SAID SPINDLE AND PROVIDING FOR THE SUPPORT MEANS TO BE MOVABLE AXIALLY WITH THE SPINDLE BUT WITHOUT ROTATION; A CRADLE HAVING A SLIDING CONNECTION WITH SAID ROLLER REST, THE CONNECTION PROVIDING FOR RELATIVE MOTION BETWEEN THE CRADLE AND THE ROLLER REST IN A DIRECTION TOWARD AND AWAY FROM SAID AXIS AND THE CRADLE BEING FORMED WITH AN ARCUATE GUIDEWAY; A TRACER VALVE CONNECTED WITH SAID CRADLE AND COOPERATING WITH SAID TEMPLET;