US2578229A - Draw plate - Google Patents

Description

119% 1951 M. R. CLEMENT ET AL 2,578,229

DRAW PLATE Filed Jan. 27, 1948 4 Sheets-Sheet l 7 U U Ilvvs/vrofls: 27 2 3 MARceL CLEMENT AND DAN/EL E. GERMA/N Dec. 11, 1951 M. R. CLEMENT ET AL 2,578,229

DRAW PLATE Filed Jan. 27, 1948 4 Sheets-Sheet 2 IN l/E/VTORS MARCEL R CLEMENT AND DAN/1. E GERMA/lv '7} be 1951 M. R. CLEMENT ET AL DRAW PLATE 4 Sheets-Sheet 3 Filed Jan. 27, 1948 I/v VE/V NA Rea CLEMENT DAN 1. E W

Dec. 111, 1951 M. R. CLEMENT ETAL 2,578,229

DRAW PLATE Filed Jan. 27, 1948 4 Sheets She t e L IN VE/VTO/VS MARCEL FF. CLEMENT AND DAN/El- E, GERMAl/V Patented Dec. 11,1951

OFFICE DRAW PLATE Marcel Ren Clement, Montreuil, and Daniel Emile Germain, Paris, France Application January 27, 1948, Serial No. 4,504 In France November 17, 1947 1 Claim. 1

Our invention refers to improvements in the draw plates for rods, bars, tubes and similar sections.

The object of the invention is to allow not only the drawing of pieces of uniform cross-section but also to effect the drawing in one single operation without involving any changing of machine parts, of such pieces as rods, bars or tubes, of which the cross-sectional area may differ in any way throughout their length, whatever may be the shape, size and change in their crosssection.

The main point of our draw-plate, including improvements as set forth in the invention, lies in the fact that it comprises a set of jaws of a polygonal shape that are arranged concentrically with the drawing axis, while leaving around the axis an opening through which may pass the piece to be drawn and the jaws are placed next to each other, with each side touching the adjacent jaw; these jaws are assembled together in a suitably shaped set up so that the cooperating sides may slide against each other and so that this motion may open up a passage way of varying section that may be adjusted to any particular cross-sectional area to correspond with the shape that it is desired to give the piece that is being drawn. Such an adjustment may be made at the start for pieces of uniform cross-section, or it may be changed during the drawing process through a mechanical means of control in the case of pieces for which the cross-sectional area is to be altered as the drawing is carried on, so that the pieces may be drawn out in one operation while using the same machine parts.

The invention takes in, also, certain auxiliary attachments, the use of which will appear in the detailed description given later on.

The following specification to be read with reference to the accompanying drawings submitted asan example deals with a method of carrying out the improvements as outlined above and will provide a clearer understanding of our invention. In the drawings:

Fig. 1 is a diagrammatic view showing in through section the shape and arrangement of the jaws assembled in their frame.

Fig. 2 shows a through section showing the shape of an individual jaw.

Fig. 3 shows a longitudinal section of the die through the drawing axis.

Fig. 4a is a sectional view of the die at right angles to the drawing axis i. e. through the line (1-2) of Fig. 3.

Fig. 4b is an elevational front view of the die.

Fig. 5 is a perspective view of the expanding part of the die.

The die, according to the embodiment illustrated, includes a set of jaws, eight for instance, shown in Fig. l at l-23-45Gl8 and their length is such as given for jaws No. 4 and 8 in Fig. 3 while their transversal section assumes the shape of an isosceles triangle with one chamfered vertex, as will be seen at 9 in Fig. 2

These jaws are assembled concentrically with the drawing axis it and placed side by side, so that two adjacent jaws are always in contact along one of their sides, the jaw system being held within the inner line of the ring II which line is octogonal in shape, each jaw bearing through its chamfered base on one side of this octogon. Naturally, the number of sides of the inner straightline figure within the ring will correspond with the number of jaws. The jaws assembled in this way inside the ring are shown by full lines in Fig. l and are so placed that all their apices meet together at the centre point of the ring so that there is in this case no space left around the axis Ill. It is easy to figure that if any movement is given to one of the jaws, say jaw 8 in the direction of its base, that is of the arrow 0 and since one of the vertices of the isosceles triangle is chamfered, this particular jaw may move in the direction of the arrow, with an accompanying movement of all the other jaws that will slide against each other along their cooperating sides and along the sides of the polygon through their chamfered base or side until the end 8 of the chamfered side of jaw 8 for instance, meets the end I l of the next side of the polygon that is parallel to the chamfer. The assembled group of jaws will then assume a position such as that shown by dotted lines in Fig. l, where they leave an opening around the axis l0 through which the piece to be drawn may pass. When the jaws are arranged as shown in dotted lines, the opening is at its widest and the jaws can move no further in the direction referred to.

It should be observed that the adjacent sides of the 45 angle at the apex of each triangle forming a jaw fit accurately against the sides of the adjacent triangle, the right hand sides (Fig. 2) being for instance convex while the left hand sides are correspondingly concave, for the purpose of constituting a closely packed grouping of the triangles. The fitting together of these triangles or jaws is carried to the finest degree of accuracy and these triangles are made up of a suitable material that has been subjected to the necessary treatment.

The size of the opening will depend on the amount of movement imparted to the jaws. This size of the opening will be adjusted to correspond to the cross-sectional area to be given to the piece to be drawn.

In the case of a piece in the shape of a rod, bar, tube or the like that has to be drawn with a uniform cross-section throughout its length, the required adjustment is made as the first step of operation and the opening for the particular piece considered remains the same while the drawing work is being carried out.

Furthermore, the ring H is set in the frame of the die in association with suitable mechanical means whereby the movement of the jaws inside the ring may be controlled readily from the outside of the ring at any time so that the opening may be made smaller or wider during the travel of the piece through the die, and consequently the cross-sectional area of the piece being drawn may be altered at will.

The arrangements that come within the scope of the invention and allow the drawing to be controlled in this manner are shown in Figures 3 and 4.

The jaws are held in the ring II by two cheek plates I2, l3 attached to the latter by screws of which two, 14 and I5, are shown in Figure 3. The ring ll itself is attached by screws to a bearing plate It that forms a portion of the frame of the die. It is surrounded by a wheel I? with outer spiral teeth and bears on two opposite cylindrical segments of the inner periphery of this wheel, as will be, seen at [8, l9 in Figures la-4b with these two cylindrical segments connected by cut- away segments 20, 2| the curvature of which widens out from the periphery of the ring starting from their common points of contact to either side of segment 19.

The wheel with spiral teeth H engages with a worm gearing 22 carried on the plate 16 by suitable fittings 23 (Figure 3) The worm gearing 22 carries at one end a replaceable grooved drum 24 that may be turned by means of a wire or cable 25 controlled by any suitable means.

The ring H has a sloping hole 26 drilled through it that goes also through the lower jaw 4. In this hole may move to either side of the jaw 3 lying between 2 and 4, two push-rods 21, 28 that bear through one of their ends on opposite surfaces of jaw 3, with these surfaces containing fiat parts for this purpose. The other ends of these push-rods bear on the surfaces of the grooved segments 29, 2| of the inner periphery of wheel ll.

It will be clear that if the wheel I! is turned through any small angle by means of the control drum 24, the grooved segments 20, 2| will act as a cam on either one or the other end of a push rod and these push-rods will then move the jaw 3 in one direction or the other, thus imparting an equivalent motion to all the other jaws as explained above. It will be obvious that only one of the push rods comes into action depending on the direction of rotation of the wheel, with the other push-rod only acting to keep the jaw 3 in its right position in the general set up.

The working of this device is self explanatory. Attention may be drawn further to the fact that scale divisions are marked on the grooved segments as shown in Fig. 4b. They agree with the size of the cross-sectional area of the axial opening through which the pieces have to pass the chamfered angle of the jaws.

and thus allow the adjustment of this opening at will and with a high degree of exactitude. It will be noted that both ends of the two pushrods bear on corresponding scale divisions of the two grooved segments whatever the position of the wheel may be.

It will be easily realised that the opening, through which the pieces to be drawn have to pass may be altered by acting on the drum 24 and this may take place just as well before the drawing starts as durin the actual drawing operation. Consequently adjustment may be made for drawing a piece with a uniform cross-section throughout its entire length, but this cross-sectional area may be changed as desired during the drawing procedure, without any pause in the operation and without having to replace any of the jaws or any other part of the machine, so that a piece may be obtained with a varying cross-section over its length, whatever the size and shape of the various sections drawn.

It will be an easy matter therefore, with a die according to the invention on the one hand to draw to a section that has been adjusted accurately beforehand, such items as rods, bars and tubes shaped as a prism, pyramid or cone throughout their length with a regular or irregular uniform cross-sectional area and on the other hand, to draw pieces that are similar in their longitudinal contour and of variable polygonal cross section over the length of the piece, while this change in shape may be in turn an increase and decrease in cross-sectional area. Special pieces may thus be drawn consisting of one single piece made up of several pyramid or cone frusturns of varying slopes and lengths.

The degree of accuracy to be got is of the order of mm. There is a wide range of sizes that may be given to the area of the opening through which the pieces have to pass, in practice, the range of this opening may go from 0 mm. to 14 mm. reckoned between the opposite fiat surfaces of the polygon that this opening makes. These numbers are only given as a guide and may be higher if desired.

In the particular example taken, a, selection has been made of 8 jaws but of course this number could vary; however as a working principle the lowest limit of jaws is three to give satisfactory operation. In the case of three jaws, the inside contour of the ring would take the shape of a triangle.

The maximum size -of the opening depends mainly on the size of the bevelled edge made by In fact, the greater the remaining length on the chamfered side, the greater is the movement that this side may make on the corresponding inner level surface of the ring. However, the bevelled edge must not go beyond a certain range in order to ensure that the jaws are held snugly in position.

It is advisahleto use mechanical means for controlling the drum 25. When it comes to pieces of uniform cross section throughout their length, it is better not to use a mechanical control and to employ instead a device for hand adjustment that allows the jaws to be brought into an unvarying predetermined position.

The invention, of course, is not tied down to the arrangements as set out above; on the other hand it takes in all modifications working on the same principle, more particularly in those cases where the polygonal section to be got would not be that of a regular polygon. I

The invention covers the novel articles of manufacture formed by articles obtained with dies constructed on the lines of the invention.

What we claim is:

A draw plate for rods, bars, tubes and the like adapted to provide constant and varying cross sections for said drawn members, comprising a series of interlocked jaws having a substantially triangular cross section and assembled about a drawing axis, in slidin relationship with reference to one another, a ring surrounding same and bounded inwardly by a polygonal surface the number of sides of which corresponds with the number of the triangular jaws and the length of said sides being equal to that of the bases of the corresponding triangular jaws, the triangular jaws having the outer edge facing a given diretion of angular movement bevelled oil for allowing a relative movement of the jaw along the corresponding polygonal surface side, the ring being provided with two alined elemental transversal openings parallel with, in the vicinity of and on the inside of one of the sides of its inner transverse polygonal surface, the triangular jaws adjacent to the jaw sliding over said sides of the polygonal surface having a recess wide enough to always register with the alined ring openings, the general angular shifting of the jaws round the drawing axis corresponding to a sliding of the jaws with reference to one another and along the sides of the polygonal surface providing for a gradual modification of the inner polygonal opening defined by the non bevelled lateral surfaces of the triangular jaw, a helical wheel provided with the two longitudinal bored recesses arranged symmetrically with reference to an axial plane of symmetry and the depth of which increases progressively from one end to the other, means for securing rigidly inside said wheel the ring, the outer surface of which fits exactly the non recessed inner surface of the wheel, a worm controlling the rotation of the wheel, a two-part pusher rod the two parts of which bear respectively against the wall of the corresponding recess in the wheel, pass through the alined openings in the ring and through the recess in the corresponding triangular jaws and engage cooperating surfaces on the jaw separating the recessed jaws.

MARCEL RENE CLEMENT.

DANIEL EMILE GERMAIN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 629,747 Kuttler July 25, 1899 686,365 Thackray Nov. 12, 1901 871,654 Woodhead Nov. 19, 1907 1,922,770 Kornbrath Aug. 15, 1933

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