US3486358A

US3486358A - Machine for profiling annular workpieces by rolling

Info

Publication number: US3486358A
Application number: US718402A
Authority: US
Inventors: Jacob Marcovitch
Original assignee: ROTARY PROFILE ANSTALT
Current assignee: ROTARY PROFILE ANSTALT
Priority date: 1967-04-19
Filing date: 1968-04-03
Publication date: 1969-12-30
Anticipated expiration: 1986-12-30
Also published as: FR1562476A; GB1198164A; DE1752140A1; DE1752164A1; DE1989827U; US3543553A; FR1562475A; DE1989828U; GB1192839A

Description

Dec. 30, 1969 J, MARCO'VIT CH MACHINEF'OR PROFILING ANNULAR WORKPIECES. BY ROLLING Filed April 5, 1968 3 Sheets-Sheet l (/9005 Mama/47:

6y JM D 9 J. MARCOVITCH MACHINE FOR PROFILING. ANNULAR WORKPIECES BY.ROLLING Filed April 5, 1968 5 Sheets-Sheet 2 Dec. 30, 1969 J. MARc vncH I I 3,486,358

MACHINE FOR PROFILING AN NULAR WORKPIECES BY ROLLING Filed April 3, 1968 r 3 Sheets-Sheet 5 JACOB Me /wow 70,4

Arr-y United States Patent Ofi ice 3,486,358 PatentedDec. 30, 1969 3,486,358 MACHINE FOR PROFILING ANNULAR WORKPIECES BY ROLLING Jacob Marcovitch, Johannesburg, Transvaal, Republic of South Africa, assignor to Rotary Profile Anstalt, Vaduz, Liechtenstein Filed Apr. 3, 1968, Ser. No. 718,402 Claims priority, application Republic of South Africa, Apr. 19, 1967, 67/2,272 Int. Cl. B21d 53/16; B21h 1/06 US. C]. 72-91 Claims ABSTRACT OF THE DISCLOSURE A machine for profiling rings in which a mandrel is threaded loosely through the ring and inserted into a converging throat defined by the surfaces of two or more rollers, and passes through the throat. The throat runs along the lengths of the rollers, at least one of which is helically scrolled to provide a track to guide the mandrel and workpiece through the machine. The ends of the mandrel roll on at least one roller, and the outer face of the workpiece rolls on at least one other roller.

This invention relates to the profiling of annular workpieces by rolling. The workpiece is threaded loosely on to a mandrel which is supported at its ends and which bears on the inner face of the workpiece. The outer face of the workpiece bears on a roller. Relative rotation of the roller and mandrel causes the workpiece to be progressively squeezed about its circumference as it works its way, segment by segment, through the space between the mandrel and roller. The mandrel or the roller, or both, are profiled to impose a complemental profile on the workpiece. Sometimes the workpiece is surrounded by a control ring which limits its diametral spread and prescribes its outer profile.

Many machines exist which allow the above-described operation to be carried out. In particular, the known machines fall into what may be called two-roller systems and three-roller systems.

In the conventional two-roller systems, the mandrel provides one of the rollers, the roller bearing on the outer face of the workpiece providing the second. The mandrel is mounted in bearings.

In the conventional three-roller systems, the workpiece and mandrel are confined in a space defined by the surfaces of three rollers, the ends of the mandrel roll ing on two of the rollers and the outer face of the workpiece bearing on the third.

In both these systems, extensive deformation of the workpiece can only be achieved if the axes of the rollers are movable over a considerable distance relative to each other. This means the machine must have a mechanism to regulate the relative movement of the axes of the rollers, so adding to the complexity and hence the cost of the machine, as also of its operation and maintenance. Moreover, the production rate is limited because each profiling operation is accompanied by an advance and withdrawal of the rollers relatively to each other as the workpiece is loaded, profiled and then unloaded.

A variant on the two-roller system has been proposed in the form of a system in which the mandrel is not a fixture in the machine but advances with the workpiece through a space defined between two rollers, one of which bears on the outer face of the workpiece, the second supporting the ends of the mandrel. The workpiece moves transversely to the axes of the rollers. The amount of deformation imposed on the workpiece is dictated by the size and curvature of the rollers. In a development of this system, the maximum deformation possible is increased by superimposing on the natural convergence of the profiling space a relative movement of the rollers to narrow the space after the workpiece has been nipped in it. In this modification there must again be a mechanism to regulate the movement of the roller axes; and the production rate is also low.

Numerous machines exist for profiling solid workpiecesfor instance making ballsby passing a solid workpiece such as a rod into and along a convergent throat defined by the surfaces of at least two rollers, the workpiece rotating about its axis and simultaneously advancing in the direction of its axis. The direction of advance of the workpiece is along the lengths of the rollers. If the rollers are of generally constant diameter, they are arranged with their axes slightly convergent to provide the convergence in the throat. If the rollers are tapered, their axes may be parall l. In either case, the roller axes are fixed. The workpiece is profiled--for in stance cut into lengths that are each deformed to form a ba1l-by contact with helical scrolls or similar formations on the surfaces of the rollers. This arrangement has the advantage that the feed to the machine can be continuous, and no mechanism is necessary to advance or withdraw the axes of the rollers relatively to each other as the operation proceeds. Thus production rates can be high, and the machine is relatively inexpensive to build and operate (apart from the cost of the rollers, which may be difiicult to make). However, machines of this system clearly cannot profile annular workpieces, unless they are supported internally by a tight-fitting mandrel.

The object of this invention is to provide a machine for the profiling of annular workpieces which allows extensive deformation to be carried out at high production rates.

A more particular object is to provide a rolling machine for profiling annuli in which extensive deformation can be carried out without relatively moving the roller axes, and through which workpieces can be passed in rapid succession while the machine is running at full speed.

Accordingly the invention provides, in a machine for profiling annular workpieces comprising at least two rollers with juxtaposed surfaces defining a convergent throat which extends in the direction of the lengths of the rollers, at least one of the rollers being rotatable about its axis, formations on the roller surfaces to squeeze a workpiece located in the throat and cause it to be profiled, and means to rotate at least one roller about its axis to impose rotation on the workpiece; the improvement of a mandrel adapted to be threaded loosely through the workpiece with its ends projecting from the workpiece, the outer face of the workpiece being adapted to roll on the formation of at least one of the rollers while the workpiece rotates and simultaneously advances along the throat, the formation on at least one other roller being lands on which the ends of the mandrel are adapted to roll while the mandrel advances with the workpiece along the throat.

If two rollers are provided, they may be rotated at different peripheral speeds so that a workpiece and mandrel inserted into the machine at one side of the plane defined by the roller axes will emerge from the machine at the other side of that plane. In other words, the workpiece will have a component of motion at right angles to its direction of advance along the throat. This additional component will enhance the deformation which can be achieved as a result of the convergence of the throat. The rollers may be mounted with convex surfaces facing each other to define the throat, or one may be hollow with the second located eccentrically within it. There can also be a two-roller arrangement in which one roller is mounted eccentrically within another, in which case the throat is annular.

With a three-roller system, the workpiece is entrapped in the space between the roller surfaces and it will normally advance rectilinearly along the throat. All three rollers rotate at the same peripheral speed at any point along the length of the throat.

The profiling formation on the rollers will generally be a scroll extending helically round the rollers. The scroll may be salient or recessed. In some cases the formations can he plain cylindrical surfaces, providing a track for the workpiece or mandrel.

Various embodiments of the invention are described below with reference to the accompanying drawings, in which:

FIGURE 1 is a semi-diagrammatic end view of a machine for profiling annular workpieces, the machine having three juxtaposed rollers;

FIGURE 2 is a side view of two of the rollers of the machine of FIGURE 1, the third roller being removed to illustrate the position of the workpiece and mandrel;

FIGURE 3 is a fragmentary, simplified view of an edge of one of the scrolled rollers of the machine of FIGURES 1 and 2, illustrating the manner in which the mandrel and workpiece and control ring are located;

FIGURE 4 is a fragmentary view of one form of plain roller for use in the machine of FIGURES 1 to 3;

FIGURE 5 is a semi-diagrammatic end view of a tworoller machine for profiling annular workpieces;

FIGURE 6 is a side view of a scrolled roller which might be used in the machine of FIGURE 5, a mandrel and workpiece also being shown located on the roller; and

FIGURE 7 is a semi-diagrammatic side view, partly in section, of another two-roller machine for profiling annular workpieces, one roller being hollow and the second contained within it.

The machine of FIGURES l and 2 has three

rollers

10, 11 and 12 juxtaposed to each other to define a throat within which an annular workpiece 13, threaded over a mandrel 15 and contained within a control ring 14, is profiled. The throat extends along the length of the rollers. The rollers rotate about their axes. The rollers and 11 are geared to each other and driven by means well known in the art and not illustrated. The third roller 12 idles, although it, too, could be driven.

As seen in FIGURE 2, the

rollers

10 and 11 have recessed scrolls in their surfaces in the form of helical grooves 16. The surfaces 19 between the grooves 16 are formations in the form of plain cylindrical lands on which the ends 18 of the mandrel roll. The mandrel is thus sturdily supported at its ends, and it is kept axially in place relatively to the

rollers

10 and 11 by a head 20 at one of its ends which protrudes into the grooves 16. The control ring and workpiece also extend into the grooves 16, without touching the bottom of the grooves, and are thus held axially in place with respect to the mandrel and

rollers

10 and 11. The surface of the roller 12 is plain and, as seen in FIGURE 1, it bears on the outer face of the control ring.

The throat defined between the

rollers

10, 11 and 12 converges from right to left in FIGURE 2. The helical grooves 16 are of the same pitch and hand and are in register. An assembly of workpiece, mandrel and control ring is inserted in the throat at the right-hand end when the ends of the scrolls, which are single-start, register at that end of the machine. The assembly is then entrained in the throat and drawn through it as the

rollers

10 and 11 are driven in the direction indicated by the arrows in FIGURE 1. The outer face of the control ring bears on the plain roller 12 and drives it frictionally. The assembly advances from right to left rectilinearly through the throat, as indicated by the arrow in FIGURE 2.

As the assembly advances down the throat, its convergence causes correspondingly increased squeezing pressure on the workpiece and so imposes the profile of the mandrel and control ring on the inner and outer faces of the workpiece. Ultimately the diameter of the workpiece will have increased to the point where it is a tight fit in the control ring. The machine will be so operated that, when the assembly has traversed the throat and emerges at the far end, profiling will be complete.

Convergence of the throat can be induced by any of several factors, as well known in the art. If, as illustrated in FIGURE 2 the rollers are of substantially constant diameter (except, of course, where indented by the grooves 16), they may be mounted in the machine with their axes slightly convergent. Another possibility is illustrated in FIGURE 3. Here the scrolled

rollers

10, 11 are stepped along their length, the final (left-hand) portion of the roller being of constant diameter so that a finishing operation akin to burnishing is given to the workpiece in the last stage of the operation. (For clarity of illustration, the scrolls are shown as annular grooves in FIG- URE 3. Equally, as illustrated in FIGURE 4, exag gerated for the sake of clarity, the roller 12 might be of increasing diameter along the length of the throat. The increase in diameter need not be uniform. For instance, in FIGURE 4, there is a portion A of constant diameter, provided to allow the assembly of workpiece, mandrel and control ring to be easily loaded into the machine, followed by a gently rising zone B, a more abruptly rising Zone C in which the bulk of the deformation is imposed on the workpiece, a further gently rising zone D, in which deformation reaches or nears its end, and a final zone E of constant diameter in which the burnishing or finishing operation takes place before the assembly is ejected.

Another possibility is that, during profiling, one of the rollers is made to approach the others relatively; for instance the roller 12 might be mounted for bodily movement relatively towards the

other rollers

10 and 11. This arrangement has the disadvantages, however, that a mechanism to regulate this movement must be provided, and further that each workpiece must pass through the full length of the throat before the next is introduced into it, so slowing up the production rate, If the roller axes are fixed and convergence is provided by other means, one assembly can be inserted in the machine on each revolution of the rollers; that is, when the ends of the scrolls are in register at the right-hand end of the machine. If the scrolls were double-start, two assemblies might be inserted into the machine on each revolution, so doubling the production rate.

It is apparent that the amount of convergence in the throat, and consequently the extent of deformation imposed on the workpiece, can be very large.

From FIGURES 2 and 3 it will be seen that the control ring 14 is bevelled at its sides to fit cleanly into the grooves 16 of both

rollers

10 and 11. This allows the mandrel axis to advance rectilinearly along the throat, as shown by the arrow in FIGURE 2.

FIGURES 5 and 6 show a two-roller machine. The

rollers

21, 22 are juxtaposed with a scroll on roller 21. Roller 22 is smooth-surfaced. Convergence of the throat 24 between the rollers along their lengths is effected by coning the

rollers

21, 22 or either of them, or by inclining their axes to each other. Both rollers are driven, as shown by arrows. The mandrel 25 rolls on the lands 28 of the roller 21, and the workpiece 26, in the control ring 27, is guided and driven by the scroll recess along the throat and is profiled by pressure against the mandrel and the control ring, or both. If the control ring imposes a profile on the workpiece, it must always be one that will permit demounting of the finished workpiece.

In addition to advancing along the length of the rollers, the workpiece is given a component of motion in a direction from one side to the other of the plane defined by the axes of the rollers. This component is governed by adifferential peripheral speed of the

rollers

21 and 22. The rollers are arranged and dimensioned to nip the mandrel and the workpiece, (and the control ring, if one is used on insertion at one side of the machine, as seen in FIG- URE 5, and to entrain the assembly through the throat. The differential peripheral speed, in relation to the diameter of the workpiece, is so chosen that, during the time taken to traverse the full length of the rollers, the workpiece will also pass from side to side of the plane defined by the roller axes. The resultant direction of motion of the assembly is shown by the arrow in FIGURE 6. The axis of the mandrel will normally, as seen by the line XX in FIGURE 6, not move parallel to the throat 24 but perpendicular to the direction of the scroll. However, if desired, it may be kept parallel to the throat but the control ring should then be bevelled, as shown in FIG- URES 2 and 3, to permit it clearing the sides of the scroll grooves.

In the machine of FIGURES 5 and 6, it is clear that the amount of deformation imposed on the workpiece can be far greater than that which would be imposed merely by passing the workpiece from side to side of the rollers. Deformation obtained by this transverse passage through the throat is, as it were, superimposed on that obtained by the translation of the workpiece along the throat.

The main advantage of two-roller systems of the type shown in FIGURES 5 and 6 is that a rest or support for the mandrel assembly is unnecessary during profiling.

Machines such as are shown in FIGURES 5 and 6 are unbalanced and therefore must be built massively to withstand unbalanced forces of great magnitude. The machine shown in FIGURE 7 does not suffer from this disadvantage. Here, a roller 40 with a recessed scroll 41 is mounted for rotation concentrically in a hollow roller 42. The annular throat 43 between the rollers converges, by making the inner roller 40 or the outer roller 42, and preferably the latter, conical. A chute 44 guides annular workpieces 45 containing mandrels 46 into engagement with the scroll outside the roller 42, the workpiece and a head 47 on the mandrel entering the scroll in adjacent turns. The workpieces may be contained within control rings. The workpieces are entrained by the scroll into the throat and advance through it as the roller rotates. The feed is such that the workpieces space themselves around the circumference of the rollers, and the machine is substantially dynamically balanced. A high throughput is therefore possible without needing a machine that is impractically massive.

The workpieces fall gravitationally from the end of the scroll and are separated from the mandrels and from the control rings, if these have been used.

The machine of FIGURE 8 has the further advantage that the hollow roller 42 can be kept stationary, and only the roller 40 need be driven.

I claim:

1. In a machine for profiling annular workpieces, comprising at least two rollers with juxtaposed surfaces defining a convergent throat which extends in the direction of the lengths of the rollers, at least one of the rollers being rotatable about its axis, formations on the roller surfaces to squeeze a workpiece located in the throat and cause the workpiece to be profiled, and means to rotate at least one roller about its axis to impose rotation on the workpiece; the improvement of a mandrel adapted to be threaded loosely through the workpiece with its ends projecting from the workpiece, the outer face of the workpiece being adapted to roll on the formation of at least one of the rollers while the workpiece advances along the throat, the formation on at least one other roller comprising lands on which the ends of the mandrel are adapted to roll while the mandrel advances with the workpiece along the throat.

2. The machine of claim 1 in which there are two non-concentric rollers; including means to rotate the rollers at different peripheral speeds so that a workpiece inserted into the machine at one side of the plane defined by the axes of the rollers will emerge from the machine at the other side of that plane.

3. The machine of claim 1 in which there are two concentrically mounted rollers that define an annular throat.

4. The machine of claim 1 in which there are three rollers defining a throat through which the workpiece is adapted to advance substantially rectilinearly, the workpiece rolling on the surface of one of the rollers and the ends of the mandrel rolling on registering lands on the other two rollers.

5. The machine of claim 1 in which the formation on at least one of the rollers is a helical scroll.

6. The machine of claim 5 in which the scroll is recessed.

7. The machine of claim 5 in which the scroll is salient.

S. The machine of claim 1 in which a roller on which the ends of the mandrel roll is recessed between the lands to provide a groove to accommodate the workpiece.

9. The machine of claim 1 in which the axes of the rollers are fixed.

10. The machine of claim 1 including a control ring surrounding the workpiece and being adapted to roll on a roller on which the outer face of the workpiece would otherwise roll.

References Cited UNITED STATES PATENTS 1,417,324 5/1922 Holmes 72-103 2,060,087 11/1936 Klamp 72-103 3,345,845 10/ 1957 Marcovitch et al. 7291 RICHARD J. HERBST, Primary Examiner US. Cl. X.R. 72-96, 104