US2062640A

US2062640A - Process for forming nuts and the like

Info

Publication number: US2062640A
Application number: US656126A
Authority: US
Inventors: William L Clouse
Original assignee: National Machinery Co
Current assignee: National Machinery Co
Priority date: 1933-02-10
Filing date: 1933-02-10
Publication date: 1936-12-01
Anticipated expiration: 1953-12-01

Description

Dec. 1, 1936. w. L. CLOUSE 2,062,640

PROCESS FOR FORMING NUTS AND THE LIKE Filed Feb. 10, 1933 3 Sheets-Sheet l Dec. 1, 1936. w. L. CLOUSE 2,062,640

Pa'ocEss FOR FORMING NUTS AND THE LIKE Filed Feb. 10, 1953 s Sheets-Sheet? J V/LA/ M Z. Claus;

Summer:

orneg 1936- w. L. CLOUSE- 2,062,640

PROCESS FOR FORMING NUTS AND THE LIKE Filed Feb. 10, 193: v a Sheets-Sheet a WILL/AM L M/155.,

Patented Dec. 1, 1936 UNITED STATES PROCESS FOR FORMING NUT AND THE LIKE William L. Clouse, Tifiin, National Machinery Co corporation of Ohio Ohio, assignor to The pany, Tiffln, Ohio, at

Application February 10, 1933, Serial No. 656,126 43 Claims. (Chm-86) This invention relates to the manufacture of nuts, and specifically to a cold working process for forming nut blanks.

It has heretofore been proposed to manufacture nuts by shearing off blanks from a length of rod or wire stock, confining the blanks in dies of a hexagonal or other suitable polygonal shape, forcing plungers axially into the blanks from the opposite sides thereof to upset the metal outwardly into the polygonal die and partially pierce an axial opening, and subsequently punching out the web of metal left between the two plungers to complete the axial opening.

A great many difiiculties have been encountered in attempting to carry out this process on cold metal. It is found that it is extremely diificult, if not impossible, to cause the metal to flow outwardly into the corners of the nut at the intersection of any two of the fiat sides and the top or bottom surface. The metal can be forced outwardly into the corners more easily by using relatively pointed plungers, but if this is done a greater length of metal is left in the blank to be sheared away in punching out the axial opening which tends to result in the metal breaking away instead of shearing off cleanly, leaving recesses or pits extending outwardly past the desired diameter of the axial opening. As a consequence, it is necessary to make the plungers O relatively blunt, and if it is attempted to force such plungers too closely together in the blank in order to obtain sufficient flow of the metal to fill out the die, the central web in the blank Cir between the two plungers is work hardened to such an extent as to render it impractical to make the plungers live under the excessive forging pressure.

Another difficulty encountered in attempting to carry out this process is the breaking on" of the plungers in attempting to withdraw the same resulting from the metal of the blank locking about the sides of the plunger. As used heretofore, the plunger has been attached or made a part of that portion of the tool which serves as a shoulder or face which finally comes in contact with and upsets or flattens the face of the nut blank. With thistype of tool when the upsetting pressure is applied to the face of the nut blank by this shoulder it causes the stock in the blank to upset and look around the reduced end of the plunger which is at that time irnbedded in the blank. This locking efiect is so great that it" becomes almost impossible to extract the plunger from the hole without breaking it off from the remainder of the tool unless a fairly large amount of draft or taper is provided on the sides of the plunger. Such draft or taper is, of course, highly undesirable as it greatly increases the length of attachment of the wad to the blank and makes it more difficult to finally punch the hole without the tendency of the stock to break away in the hole.

Other efforts have been made to avoid these difficulties by initially forming the blank dome shaped on its two opposite ends so as to avoid the necessity of filling out the corners by leaving a chamfer on each face of the nut. This idea of double dome shaped surfaces on the two opposite ends of the blank does not correct the trouble, for it does not eliminate the necessity of bringing the two blunt faced plungers too closely together, or if morepointed faced plungers are used it still allows too great a length of metal to be sheared away in punching out the axial opening, thus causing the aforesaid recesses or pits beyond the diameter of the axial opening, which reduces the bearing area of the threads which are afterwards cut in the sides of this opening. Furthermore, this solution is not suitable because the double chamfered nut produced thereby is not as desirable a product as one in which the corners between the fiat polygonal faces and the bottom face are filled out.

I have solved these difliculties in the cold, working process of making nuts by directing the metal flow to fill .out first one and then another portion of the blank in the dies and also by holding and acting upon the blank during each operation in such a manner that the metal'is never completely confined, but may flow freely at all times in one direction or another so as to definitely limit the pressures developed in the metal to the pressure required to flow the metal into a free or open space and thereby to avoid excessive deterioration of the tools or the looking of the metal about the plungers or tools.

Broadly, my invention consists of one or more cold working operations upon a blank to spread the metal radially into a polygonal die and to produce in either the same or subsequent operations radial and axial flow of the metal to substantially fill out the different parts of the die cavity, and finally punching out the metal in the center of the blank to form an axial hole.

My invention also includes a number of broad improvements in individual operations which may be employed in combination with theother steps disclosed or which may be incorporated in other processes to realize their accompanying advantages. These improvements are flowing the metal in an upsetting operation more towards one end surface of the blank than toward the other, permitting a concentration of the available pressures to cleanly fill out one portion of the blank in the die; upsetting and piercing the blank from one end surface while leaving that end surface unconfined to permit a wave of metal, including any surplus metal, to be thrown up about the piercing tool, thereby limiting the pressure developed by the piercing tool and avoiding upsetting and locking the metalabout the tool; flattening or shaping one or both of the end surfaces of the blank by exerting pressure thereon after the piercing tool has been partially or completely withdrawn, or at least relieved so as to allow a free flow of any surplus metal in the blank into the opening formed by the piercing tool or tools to dispose of such surplus metal and likewise limit the pressures developed; piercing or upsetting the wad of metal left in the blank by the initial operation or operations by exerting pressure thereon from one side only to flow a portion of the metal outwardly into the die and reduce the axial length of the attachment of the wad to the blank; shearing out the wad and any surplus metal by axial punching while the blank is gripped in a die and held against distortion; and combining and timing the punching operation with a piercing or end shaping operation in a single die so that the punching follows a pressure operation without intermediate releasing of the blank from the die.

In carrying out my invention I prefer to perform the first operation by pressing a plunger into the blank from one end surface through more than half of the axial length of the blank to flow the metal to the opposite end surface and fill out the corners. During this operation the opposite end surface may be either allowed to abut against a flat faced tool or may be partially pierced by a relatively short plunger. Preferably the face of the blank into which the plunger enters is not engaged by the tool while the plunger is within the blank, but the metal is allowed to be thrown up in a wave about the plunger. Subsequently, pressure is exerted against this face by a finishing tool. This is accomplished by constructing the plunger or piercing tool so that throughout the operation the end surface of the blank into which the piercing tool enters is unconfined in an axial direction over the area between the piercing tool and the walls of the die, or in other words, radially outward of the piercing tool.

In the preferred embodiment of my invention the blank is pierced through more than half of its axial length from one end surface in the first operation, filling out the opposite end surface and leaving a wad of metal in the blank. In the second operation a plunger is pressed into the blank from the side which has been filled out during the first operation to flow the metal of the wad remaining in the blank primarily in the opposite direction to fill out the other end surface of the blank, which may abut against a finishing tool of any desired form, and to reduce the axial length of the attachment of the wad to the blank. As in the first operation the metal is allowed to creep up about the plunger in a wave without being engaged by the tool on the end surface at which the plunger enters. At the completion of the second operation I prefer to exert pressure on the opposite end surfaces of the blank by tools designed to finish these surfaces, allowing any excess metal to .flow freely into the hole which has been formed by the plungers in the first and second operations. I then shear out the metal in the center of the blank while the blank is retained in the die to complete the formation of the axial hole. If desired the shearing may be accomplished by punching in the open. The operation of finishin and flattening the end surfaces of the blank after the piercing operations may conveniently be combined with either the second piercing operation, the final punching operation or may be performed separately. The operations may be combined by making the tool for finishing the end surface in the form of a sleeve surrounding either the plunger or the punch so that while the blank is retained in the same dies, first one of the tools and then the other may be advanced into engagement with the blank. Preferably this operation is combined with the punching so that the blank may be'gripped in a die, subjected to pressure, and then punched without releasing the blank.

It will be understood that the second piercing operation which flows the metal primarily in the opposite direction to that in which it was caused to flow by the first operation is directed in axial alignment with the opening formed in the first piercing operation and flows the metal so as to greatly reduce the axial length of the attachment of the wad remaining in the center of the blank to facilitate the final shearing out of the wad. In some instances this second operation may be omitted.

Ordinarily it is preferred to have the nut formed with a chamfer on its upper face while the bottom face is formed with full sharp corners. Likewise it is preferable to have a small conical counter-sink in the hole on the bottom face of the nut to facilitate starting the nut on the threads of a bolt or the like and to have the hole squarely intersect the top face of the nut so as to provide the maximum length for the threads. Where piercing tools are employed having integral shoulders for flattening the end surfaces of the blank it is customary to construct the tools with a fillet between the plunger portion and the shoulder portion which forms a counter-sink in the hole with the result that both ends of the hole are counter-sunk. I avoid this by allowing the metal to creep outwardly into a wave while the plunger is within the blank and subsequently flattening out the end surface so that the hole may be formed without a counter-sink at the upper surface of the nut. Likewise the use of a dome shaped blank to avoid the necessity of filling out the metal in the corners as previously explained results in a chamfer on both faces of the nut which is undesirable. To provide a chamfer on the upper face I preferably make this face of the blank initially chamfered or bevelled and allow the metal to flow freely while exerting pressure only against the fiat portion of the upper face, in v proximately the center of the nut height or preferably past it, thereby materially reducing the length of attachment of the wad to the nut. This reduced length of attachment prevents the recessing or breaking away of the metal beyond the diameter of the hole and back of the wad portion, and insures a uniform size hole which gives a maximum bearing area to the portion to be threaded.

Another advantage of my invention is to permitt he disposal of any surplus of stock so that an accurate nut can be made from an inaccurate blank. If any surplus stock is not disposed of it causes the pressures on the tools to mount to the point of destroying the tools or at least greatly increasing the locking effect of the metal about the plunger. This is accomplished by fiattening out and finishing the end surfaces of the blank after the piercing plungers have been at least partially withdrawn or relieved and while the blank is in a die so that any surplus of metal in the blank can flow into the portion of the hole from which the plunger has been removed so that no inaccuracies can develop in either the parallelism of the nut faces or in the axial length of the completed nut. Any such surplus of stock which flows into the hole is removed with the wad in the punching operation. In this way the outside contour and thickness of the nut are perfectly maintained even though there may be a surplus of material in the original blank. Another advantage is obtained by retaining the blank gripped in the same die in which the upsetting pressure on the face of the nut has been applied during the final punching operation, as this not only provides a means to accurately guide the punch'and thereby assure concentricity of the hole with respect to the nut, but it also insures that the hole will be punched through the nut squarely at right angles to the top and bottom surfaces and without any runout of the hole such as frequently occurs when the nut is punched outside of the die. These various features of my invention combine to insure accuracy of volume in the finished nut and corresponding accuracy in the thickness and over-all dimensions; concentricity of the hole with the sides or facets of the nut; an accurately perpendicular relation between the axis of the hole and the bottom surface of the nut; and exact parallelism of the sides or facets of the nut.

I have used the expressions top and botom surfaces of the blank to distinguish between the two ends of the blank, the expression bottom surface referring to the surface of the completed nut which is normally designed for engagement with the object against which the nut is screwed down. These expressions are not intended to refer to the position of the blank during the process, since it is obvious that the process may be carried out on any suitable type of apparatus and the blank may be positioned in any desired manner. I have used the expression cold working in its usual sense, that is, working below the temperature of rapid grain growth or recrystallization; but my invention is more particularly valuable and useful in the lower temperatures of the cold working range, since at these lower temperatures, up to about 400 or 500 degrees F. difficulties from scale, sticking in the dies and shrinkage are avoided and the problem 'of cleanly shearing out the wad,

which I have solved, is more pronounced.

The terms unconfined and restricted as employed herein with reference to the metal of ,tained therein in a groove 2i.

, 3 the end of the blank indicate the metal work-,

"ing condition existing at that part of the blank.

In this connection, restricting the flow of the metal is not limited to the provision of means contacting the entire end of the blank and preventing any movement of any part of the metal, but is intended to indicate means preventing a substantial axial flow of the metal at the end of the blank. For instance, the axial flow of the metal of 'a blank is restricted where the restricting means contacts enough of the area of -the end of the blank to prevent movement of all metal subject to movement by an actuating pressure and the metal flow of a polygonal blank may thus be restricted even though the metal at the corners of the blank is not moved into engagement with the, restricting means.

In the accompanying drawings which illustrate the steps of my invention:

Figure 1 is a sectional view through a set of tools for initially shaping a blank or lozenger;

Figure 2 is a sectional view taken substantially on the line 2-2 of Figure 3;

Figure 3 is a vertical sectional view through a die showing a blank in position therein and a plunger in position before engaging the blank;

Figure 4 is a view corresponding to Figure 3 showing the plunger at the end of its upsetting firststep of another modified form of the process;

Figure 9 is a section on the line ure 8;

Figure 10 is a sectional view of the tools for carrying out the modified form of the second step of the process;

Figure 11 is a side view of a blank;

Figure 12 is a sectional view through a set of tools for carrying out the first step of a further modification of the process;

Figure 13 is a sectional view of a set of tools for carrying out the final steps on the blank initially acted on by the tools shown in Figure 12;

Figure 14 is a sectional view of the modified form of apparatus for punching out the hole-in the blank.

Figures 1 to 6 inclusive illustrate tools which may be utilized for carrying out the preferred embodiment of the process. Lozengers or blanks G are first formed in any suitable manner, ordinarily by shearing oif short lengths from rod or wire stock. The lozengers are first operated on by a die I5 and co-operating plunger l6 to true up the bottom face-of the lozengers and form a bevel or chamfer b on the upper face. The lozenger a. is then transferred or conveyed in any suitable way to a hexagonal split or solid confining die l8 for the first upsetting step. In the illustrated embodiment the die l8 has a ring l9, formed with an inner cylindrical bore 20, re-

A cylindrical plunger 22 having a flat upper face 23 fits within the bore 20 of the ring l9 and is preferably slidable for the purpose of ejecting 99 of Figcompleted nut the blank. A,

tool 24 is guided to move axially within the die impression and is formed with a piercing plunger 25 joined to the tool 24 by a conical shoulder 26.

The lozenger a is first gripped within the die l8 and the tool 24 is moved down to cause the piercing plunger 25' to enter the upper face of the lozenger and upset the same into the hexagonal die I8, leaving a hole 0 in the blank. The upsetting operation is performed in such a way as to cause the metal to spread radially outward into the confines of the die and to fiow primarily toward the fiat face 23 of the plunger 22. This flow of the metal toward the surface 23 which forms the bottom surface of the nut blank fills out the corners of the blank into the die adjacent the bottom surface and likewise flows the metal into contact with the ring |9 which is spaced radially above the tool surface 23 to form an annular recess of or washer face on the bottom of the nut. Since the piercing pressure on the metal is concentrated and directed by the plunger 25 toward the bottom face of the blank, this portion of the blank is completely filled out into the recess of the die, forming clean sharp corners.

The desired fiow of the metal is produced by forcing the plunger 25 more than half way through the axial length of the blank and also by the shape of the plunger which directs the pressure toward the lower corners of the blank. During the piercing operation the portion of the upper end surface of the pierced blank which is disposed radially outward from the piercing tool is free and unconfined in an axial direction, so

that the metal'may fiow upwardly within the die to prevent the pressure in the metal from building up sufiiciently to injure the tools. A small wave of metal e is thrown up on the top surface of the blank about the plunger 25 by the piercing action. This wave is also allowed to form freely so as to avoid locking the metal around the plunger 25. At the completion of the stroke of the tool 24, a web of metal ,1 is left in the blank in alignment with, and in advance of, the hole 0.

The tool 24 is then withdrawn and the blank removed from the die IS. The removal of the blank may conveniently be accomplished by sliding the plunger 22 forwardly so that it acts as an ejector after relieving the pressure of the die l8 on the blank. The blank in this condition is then placed in a die 2i of substantially the same construction as the die H3. The die 21 may be provided with a ring 28 corresponding to the ring l9 if desired so as to prevent deformation of the recess d which has been formed by the ring l9. In the die 21 the blank is acted upon by a pair of opposed tools, theupper tool 29 having a substantially fiat face with a central recess 30 smaller in diameter than the opening 0 formed in the blank by the plunger 25. The lower tool 3| is provided with a piercing plunger 32 joined to the tool by a conical shoulder 33. The fiat face of the tool 29 is brought down against the top surface of the blank and the piercing plunger 32 is forced into the blank from the lower suring out the corners adjacent the top surface of;

the blank, andthe excess metal is also free to flow into the hole 0. The plunger 32 is forced into the blank through more than half of the axial length of the blank and directs a flow of metal radially outward and axially to fill out the corners of the blank adjacent the upper surface, forming an opening 0 extending into the blank from the lower surface. The conical shoulder 33 of the tool 3| enters the blank a short distance forming a bevel or countersink h. at the lower end of the opening g. A wave of metal is also thrown out on the bottom surface by the action of the plunger. This wave is indicated at i and extends downwardly along the conical surface 33 as shown in Figure 5. The web of metal 3 left in the blank in advance of the opening c by the first operation is thinned out, pressed toward the upper surface of the blank, and in some cases may be broken open at the center by the action of the plunger 32. The resulting wad left between the holes 0 and g is indicated by the letter :i and is attached to the blank at its outer edges along an axial length substantially less than the length of the attachment of the web 1, which facilitates the final punching out of the wad. The flow of the metal by the action of the plunger 32 reduces the amount of metal contained in the wad by flowing a portion thereof outwardly and filling out the blank in the die adjacent the upper surface of theblank.

The wad of metal 7' pushed up by the action of the plunger 32 may, if desired, be'pressed beyond the top face of the blank and into the space provided by the recess 30 in the tool 29. The size of this recess determines the extent to which the pressures can be concentrated in order to throw the metal against the side faces of the die at the top portion of the blank. The distance through which this operation is carried .depends upon the amount of working needed in the particular blank after the completion of the first operation in order to fill out the blank in the die near its top surface.

During the second operation the pressures are prevented from building up to a point which would destroy or injure the tool by leaving portions of the blank unconfined to permit flow of any excess metal. The lower face or surface of the blank is unconfined and the metal is thrown out on this surface in the wave i. The hole 0 formed by the plunger 25 is also open allowing the metal of the wad to fiow freely toward the top surface of the blank. The chamfer I) initially formed on the blank is, however, only partially filled out in the preferred embodiment so that the blank is substantially filled out into the die near the centers of the fiat faces of the hexagon and is chamfered on the top in the manner desired in the completed nut adjacent the corners between the fiat faces.

The blank is then removed from the die 21 as by withdrawing the tool 29 and ejecting the blank out by advancing the tool 3| or in any other suitable'manner and is placed in a die 34 which is similar in all respects to the dies l8 and 21. A ring 35 may be provided in the die 34 to prevent deformation of the recess d. A tool 38 having a central bore 31 substantially equal in diameter to the desired axial opening in the nut blank is brought down against the upper surface of the blank. A corresponding tool 38 having a central bore 39 is brought up against the bottom surface of the blank. These two

tools

36 and 38 flatten and finish the top and bottom surfaces of the blank, the wave 1' formed by the tool 3| being pressed down into the metal. During this operation the metal, although confined on the outside by the die 34, is free to flow into the holes 0 and g flow into the holes.

so that the

tools

33 and 33 may be brought together to exactly define the desired height of the nut blank and any excess metal in the blank may A punch 40 is slidably disposed within the bore 39 of the tool 38 for punching out the wad in the blank and forming the axial opening. While the blank is retained in the die 34- and between the

tools

36 and 38 the plunger 40 is advanced to shear out the metal and complete the formation of the axial opening.

It will be clear that by punching the wad and any excess metal out of the blank to form the hole while the blank is held gripped in the dies 34 and between the forming

tools

36 and 38 any deformation of the previously formed blank from the action of the punch is prevented and at the same time the hole formed will be square with the top and bottom faces of the blank and exactly concentric with the periphery of the blank. At the completion of this operation the completed nut blank as illustrated in Figure 11 may be ejected from the dies 34 in any suitable manner as by sliding the tool 38 forwardly.

If desired the operation of flattening and finishing the end faces of the blank may be carried out in a separate die by means of two opposite fiat faced plungers as illustrated in Figure 7. In this arrangement the blank is shown retained in a die 49 similar in all respects to the dies i8, 21, etc., and is acted upon by two plungers 53 and 51 which are formed with flat end faces which merely abut the end faces of the blank and flatten and finish these faces. The tools 53 and 5'! are brought together so that at the completion of the stroke the fiat faces are spaced apart a distance exactly equal to the desired height of the completed nut. Any excess metal contained in the blank is allowed to flow freely into the holes and 9 formed in the piercing operations.

The process has been illustrated and described in connection with separate dies in which the various steps are performed. It will be understood, of course, that the process is in no way limited to this type of machine and might be equally well applied to the type of machine in which a lozenger is inserted in a die cavity, and then carried around by the dial into alignment with the tools for carrying out the successive operations, and finally ejected from the cavity. Similarly the process could be applied to any other suitable type or arrangement of apparatus.

It will be understod that the preferred embodiment of my invention as illustrated in-Figures 1 to 6 is not limited to the tools or apparatus, but consists specifically of piercing the blank from one end face to accurately form the portion of the blank adjacent the opposite end face in the dies while allowing the metal to flow out or form a wave on the end face at which the piercing tools enter; again piercing the blank in substantially the same manner from the opposite end face; flattening and finishing the two end faces by pressure, allowing any excess metal to flow into the holes formed by the piercing tools; and punching out the wad left in the blank. It will be understood that if it is desired to form the nut blank without the recess d or washer face that the rings set into the dies for forming this recess may be omitted. Similarly the pressure operation for flattening and finishing. the end faces of the blank may be performed in the final die by tools such as those illustrated in Figure 6, may be performed in a separate die as illustrated in Figure 7, or may be performed in conjunction die impression along with the second piercing operation. This pressure operation for finishing the end faces may be combined with the second piercing operation in the same way in which it is combined with the final punching operation; that is, by constructing the piercing plunger 32 as a tool slidable within a sleeve corresponding to the sleeve 38 so that the plunger 32 'may be pressed into the blank while the sleeve remains out of contact with the end face and then the pressure on the plunger 32 may be relieved or the plunger may be withdrawn and the sleeve pressed against the end face to flatten and finish both end faces. By relieving the pressure on the plunger 32 or withdrawing it before the pressure is applied to the end face, the metal is free to fiow into the hole 9 formed by the plunger without developing a locking effect between the blank and the sides of the plunger.

Figures 8, 9 and illustrate tools for carrying out a modified embodiment of my invention. In this embodiment the lozenger is gripped in the die impression of a split die 4| and is simultaneously pierced from the opposite end faces by a pair of

opposed tools

44 and 46. As in the previous illustrations the die may, if desired, be provided with a ring 42 having a shoulder 43 extending into the die impression for forming a recess or washer face on the bottom end face of the nut. The tool 44 is provided with a piercing plunger 45 and the tool 46 is similarly provided with a plunger 4-1. The plunger 45 is preferably made substantially longer than the plunger 41 so as to produce an axial flow of the metal primarily toward the bottom end face and thereby fill out the die impression along the sides adjacent the bottom end face into clean sharp corners. As illustrated, the flat end faces of the tools 44' and 46 are connected to the plungers 45 and 41 re spectively by conical fillets or the like 55 and 56. As shown in Figure 8 the fiat end surfaces of the

tools

44 and 46 may, if desired, be brought completely up into contact with the end surfaces of the blank. As previously pointed out, itis preferable not to bring the tools up sufliciently to exert pressure on the end faces of the blank by the end faces of the tools so as to avoid locking the metal of the blank about the plungers. In certain'instances, however, as illustrated in this embodiment it is -possibleto avoid the deformation of the end faces during the piercing operation without destroying the plungers and thereby eliminating one step of the process included in the preferred embodiment.

At the completion of the first operation as illustrated in Figure 8 the blank is transferred to dies 48 substantially similar to the dies 4| and provided with a ring 50 if desired corresponding to the ring 42. In this operation a flat faced tool 54 is brought down against the top face of the blank,'and simultaneously a tool 5! having a plunger 52 is pressed into the blank from the bottom face. This operation flows and spreads the metal of the wad left between the openings formed by the opposed plungers in the first operation radially outward and toward the top face of the blank to fill out the blank in the the sides adjacent the top portion. At the same time the plunger 52 reduces the axial length of the connection between the wad of metal and the blank and in some instances may break the wad open in the center as illus trated in Figure 10. At the completion of this operation the metal forming the wad is sheared out of the blank in any convenient way, as by a simple punch such as illustrated in Figure 14 which will be described hereinafter, or by tools such as those illustrated in Figure 6 in which the blank is retained in a die while being punched.

Another modified embodiment of my invention is illustrated in Figures 12 and 13. This arrangement is a simplified embodiment including but three operations on the blank in twodifferentstages. The lozenger a is gripped in a die 58 similar to the die l8 previously described. When it is desired to form a recess d or washer face on the nut a ring 59 is included similar to the ring l9 previously described. The blank is then pierced through more than half of its axial length by a piercing plunger 60 carried by a tool 6| similar in all substantial respects to the tool 24 and piercing plunger 25 illustrated in connection with the preferred embodiment of the invention. The bottom end face of the nut is pressed against a tool 62 similar to the tool 22 illustrated in the .preferred embodiment. The upper face of the tool 62 may, however, be provided with a projection 63 having conical side surfaces 64 to form a countersink around the opening of the axial hole in the bottom face of the completed nut. This projection 63 enters the metal of the blank and forms a correspondingly shaped depression therein during the first piercing operation.

The blank may then be transferred to. a die 65 in which the end surfaces of the blank are flattened and-finished and the axial opening is punched out as illustrated in Figure 13, these tools being substantially the same as those illustrated in Figure 6. The wave -e thrown up on the top surface of the blank by the action of the piercing plunger 60 is flattened out by

opposed tools

66 and 61 formed with

central bores

68 and 69, respectively, which are first brought up and pressed against the end faces of the blank. As in the previous operations any excess metal is allowed to fiow into the hole formed by the plunger 60. While the blank remains gripped in the dies and punch 10 which is slidably mounted in the bore 69 of the tool 61 is pressed through the blank from the lower side, shearing out the wad of metal and farming the axial hole in the blank.

This embodiment of my invention may be used where the first piercing operation in conjunction with the pressure operation for flattening out the. end surfaces provides sufficient flow of the metal to satisfactorily fill out the sides of the blank adjacent the top surface as well as the bottom surface.

Figure 14 illustrates a final punching operation for shearing out the wad in the blank which may be employed alternatively in any of the various embodiments 'of my invention. In this figure the blank is placed on a supporting plate or the like H having an opening 12 extending therethrough. The blank is disposed on the support concentric with the opening 12 and a punch I3 is forced through the blank to shear out the wad and press it down into the opening 12 to dispose of it. This arrangement for the final punching of the blank in the open may be used in conjunction with the preferred embodiment of my invention when the pressure on the end faces of the nut to flatten and finish the same is applied by separate plungers as illustrated in Figure 7 or in connection with the second piercing operation as previously described. Similarly it may be, employed in connection with the embodiment of my invention illustrated in Figures 8, 9 and 10 and may be employed with the embodiment illustrated in Figures 12 and 13 by applying the flattening and finishing pressure to the end faces of the blank by separate tools as illustrated in Figure '7.

It is to be understood that the various piercing tools may be made ofany suitable shape to produce the desired metal flow and similarly that any of the various embodiments of my invention may be carried out without the use of the ring retained in the dies which forms the washer face on the bottom of the nut. Furthermore, the counter-bore at the end of the hole in the nut may or may not be employed and where desired can be applied to both ends of the axial opening instead of only one as in the preferred embodiment. Many other variations in the shape of the tools and construction of the dies may be made. The essential feature of my invention resides in obtaining the proper metal flow as I have described it regardless of the shape and size of the tools employed.

It is to be understood that the first upsetting step fills out the central portion of the cylindrical blank into the hexagonal die and provides a greater flow of the metal toward one surface than toward the other so as to completely fill out the corners adjacent the first surface. As illustrated this is accomplished in one embodiment by using but one plunger which enters the blank through substantially more than half of the axial length of the blank after it has been pierced and in another embodiment by using two opposed plungers and moving one plunger a greater distance into the blank than the other. This upsetting operation is preferably employed in combination with the other steps I have disclosed, although it may, if desired, be substituted for the upsetting step in other processes.

The second piercing operation as disclosed in the preferred embodiment of my invention may in some instancesQas explained, be omitted altogether, but preferably is used to reduce the length of metal to be sheared out in finally punching the axial opening and also to flow the metal into the corners of the blank opposite those to which the flow is obtained by the first upsetting step. This operation may extend through different distances, depending upon the amount of working required and may or may not break open the central web in the blank, but preferably is continued through more than half the axial length of the blank as disclosed in the preferred embodiment. This operation may likewise be added or used in other processes to obtain the advantages in preparing the blank for the punching operation and filling out the corners. It will also be understood that if desired the chamfer at the corners on the top surface of the nut may be omitted and these corners of the nut completely filled out in the dies by the second upsetting step.

Similarly the novel step of flattening and finishing the end faces of the blank and reducing the blank to the exact height or axial length desired, allowing any excess metal to flow into the holes which have been pierced may be employed in conjunction with other preliminary forming operations and may be incorporated in other processes.

Although I have disclosed specific. illustrations of my invention and'have likewise shown preferred forms of tools for carrying outthe various steps, it is to be understood that my invention is not limited thereto and that various modifications and re-arrangements of the steps of the intermediate the ends of the blank and thereafter punching out the wad to form a hole through the blank.

2. A process of making nuts including upsetting a blank to polygonal shape by partially piercing the same from opposite sides leaving a web of metal within the blank, reducing the thicknessof the web within the blank bypiercing the same from one side and subsequently with a separate tool shearing out the metal of the web to form a hole extending completely through the blank.

3. A process of making nuts by cold working including upsetting a blank to polygonal shape by partially piercing the same from opposite sides leaving a web of metal within the blank, reducing the thickness of the web within the blank bypiercing the same from one side and subsequently shearing out the metal of the web to form a hole extending completely through the blank.

4. A process of forming nuts comprising upsetting a blank by partially piercing the same through at least half of the axial length of the pierced blank leaving a web of metal within the blank, flowing the metal of the blank outwardly by piercing the web from one side only, and with a separate tool shearing out the metal of the web to form an opening extending completely through the blank.

5. A process of making nuts comprising upsetting a blank by piercing the same from its opposite sides leaving a web of metal within the blank, exerting a force against the web to move the same axially within the blank and to flow a portion of the-metal thereof outwardly and shearing out the remainder of the web to form a hole completely through the blank.

6. A process of making nuts including upsetting a blank by piercing the same from one end of the blank through at least half of the axial length of the pierced blank, leaving a wad of metal within the blank, exerting a pressure against the wad from the opposite end of the blank to fiow a portion of the metal of the wad outwardly and with a separatetool shearing out the remainder of the metal of the wad.

7. A process of making nuts by cold working including the step of upsetting a blank into a polygonal die by piercing the same axially from one end surface through more than half the axial length of the pierced blank while leaving that end surface of the pierced blank radially outward of the piercing tool unconfined in an axial direction throughout said piercing, and finally punching out the wad of metal in alignment with the pierced hole from the opposite end surface.

8. A process of making nuts by cold working including the steps of upsetting a blank by piercing the same axially from one end surface of the blank while leaving the metal of that end surface of the pierced blank radially outward of the piercing tool axially unconfined and restricting axial fiow of the metal of the opposite end sur-' face and shaping the end surfaces of the blank by exerting pressure thereon while leaving the metal defining the pierced hole unconfined throughout said shaping operation.

9. The process of making nuts by cold working including piercing a blank from the opposite end surfaces, leaving one end surface of the pierced blank unconfined in an axial direction throughout said piercing over an area radially outward of the piercing tool and restricting axial flow of the metal of the opposite end surface, shaping a portion of the end surfaces by exerting pressure thereon while leaving the metal defining at least a portion of the pierced hole unconfined throughout said shaping operation and punching out the metal in the blank to form an axial opening.

10. The process of making nuts by cold working including piercing a blank from one end surface through more than half the axial length of the pierced blank while leaving that end surface of the pierced blank unconfined in an axial direction over an area radially outward of the piercing tool, piercing the blank from the opposite end surface through a relatively short axial length, shaping a portion of the end surfaces of the blank by exerting pressure thereon while leaving the metal defining at least a portion of the pierced opening unconfined throughout said shaping operation and punching out the metal in the blank to form an axial opening.

11. The process of making nuts and the like including partially piercing a blank from its opposite ends, leaving a web of metal within the blank, flowing the metal of the web by exerting a pressure thereagainst by a relatively pointed piercer from one end surface only, and punching out the remainder of the web to form an axial opening through the blank.

12. The process of making nuts including confining a blank in a polygonal die, upsetting the metal into the die by partially piercing the blank through more than half the axial length of the pierced blank from one end surface, piercing the blank from the opposite end surface through a relatively short axial length, leaving a web of metal in alignment with the pierced hole, flowing a portion of the metal of the web outwardly and further. upsetting the blank by exerting a pressure against the web from the opposite end surface only and shearing out the metal of the web.

13. The process of making nuts by cold working including the steps of partially piercing a blank axially while leaving at least one end surface of the pierced blank unconfined in an axial direction over an areas radially outward from the piercing tool, and shaping the end surface of the blank by exerting pressure thereon while leaving the metal defining at least a part of the pierced hole unconfined throughout said shaping operation.

14. The process of making nuts by cold working including the steps of partially piercing a blank axially from one end surface through more than half of the axial length of the pierced blank while leaving the metal of that end surface unconfined in an axial direction over an area radially outward of the piercing tool and shaping the end surface' of the blank by exerting pressure thereon while leaving the metal defining at least part of the pierced hole unconfined throughout said shaping operation.

15. The process of making nuts by cold working including the steps of partially piercing a blank axially from one end surface through more than half of the axial length of the pierced blank while leaving the metal of that end surface unconfined. in an axial direction over an area radially outward of the piercing tool and shaping the end surface of the blank by exerting pressure thereon while leaving the metal defining at least partrof the pierced hole unconfined throughout said shaping operation, and punching out an axial hole in the blank in alignment with the pierced hole.

16. The process of making nuts by cold working including the steps of partially piercing a blank axially from one end surf-ace through more than half of the axial length of the pierced blank while leaving the metal of that end surface unconfined in an axial direction over an area radially outward of the piercing tool and shaping.

the end surface of the blank by exerting pressure thereon while leaving the metal defining at least part of the pierced hole unconfined throughout said shaping operation, and punching an axial surface While leaving that end surface unconfined in an axial direction over an area radially outward of the piercing tool, piercing the blank from the opposite end surface to form opposed pierced holes separated by a web of metal and punching out the web of metal to form an axial hole in the blank.

18. The process of making polygonal nuts by cold working including piercing a blank from the opposite end surfaces, leaving one end surface of the blank unconfined in an axial direction over an area radially outward of the piercing tool and restricting axial fiow of the metal of the opposite end surface to form opposed pierced holes in the blank separated by a web of metal and punching out the web of metal.

19. The process of making polygonal nuts by cold working including piercing a blank from one end surface through more than half of the axial length of the pierced blank while leaving that end surface unconfined in an axial direction over an area radially outward of the piercing tool, piercing the blank from the opposite end surface through a. relatively short axial length and punching out the web of metal between the two pierced holes.

20. The process of making nuts by cold working including piercing a blank from the opposite end surfaces, leaving one end surface of the pierced blank unconfined in an axial direction over an area radially outward of the piercing tool and restricting axial fiow of the metal of the opposite end surface, shaping the end surface by exerting pressure thereon while leaving the metal defining at least a portion of the pierced hole unconfined throughout said shaping operation and punching out the metal in the blank to form an axial opening.

21. The process of making nuts by cold working including piercing a blank from one end surface through more than half the axial length of the pierced blank while leaving that end surface unconfined in an axial direction over an-area radially outward of the piercing tool, piercing the blank from the opposite end surface through a relatively short axial length, shaping the end surfaces of the blank by exerting pressure thereon while leaving the metal defining at least a portion of the pierced opening unconfined throughout said shaping operation and punching out the metal in the blank to form an axial opening.

22. The process of making nuts by cold working'including confining a blank in a polygonal die, partially piercing the blank axially to upset and spread the metal into the die leaving a web of metal in the blank, exerting a pressure on the web from one side only in such a manner as to flow a portion of the metal of the web outwardly and toward the opposite end surface of the blank and reduce the axial length of the attachment of the web to the blank, and punching out the remainder of the web to form an axial opening through the blank.

23. The process of making nuts and the like including partially piercing a blank from at least one end surface through more than half of the axial length of the, pierced blank leaving a web of metal within the blank, flowing the metal of the web by exerting a pressure the'reagainst from the opposite end surface only and with a separate tool punching out the remainder of the web to form an axial opening through the blank.

24. The process of making nuts by cold working including piercing a blank through more than half the axial length of the pierced blank from one end surface leaving a web of metal in alignment with the pierced hole, flowing the metal of the web by exerting a pressure against the same from the opposite end surface only, relieving such pressure, and then punching out the remainder of the web.

25. The process of making nuts by cold working including confining a blank in a polygonal die, upset-ting the metal into the die by partially piercing the blank through more than half the axial length of the pierced blank from one end surface leaving a web of metal in alignment with the pierced hole, fiowing a portion of the metal of the web outwardly and further upsetting the blank by exerting a pressure against the web from the opposite end surface only, relieving such pressure, and then shearing out the metal of the web.

26. The process of making nuts by cold working including upsetting a blank by partially piercing the same axially leaving a web of metal in the blank, further upsetting the metal by exerting a pressure against one side, of the web while leaving the opposite side thereof unconfined, relieving the pressure, and finally punching out the web to form an axial hole through the blank. 27. The process of making nuts by cold working including confining a blank in a polygonal die, upsetting the blank by partially piercing the same to spread the metal outwardly into the die leaving a web of metal in the blank, further upsetting the blank by exerting pressure against one side of said web while leaving the opposite side thereof unconfined and with a separate tool punching out the web to form an axial opening through the blank.

28. The process of making nuts by cold working including partially piercing a blank axially leaving a web of metal within the blank in alignment with the pierced hole,,fiowing the metal of the web by exerting pressure thereon from one side while leaving the opposite side of the web unconfined and leaving part of the end surface of the blank from which the pressure is applied unconfined in an axial direction, and punching out the web to form an axial opening through the blank.

29. The process of making nuts by cold working comprising confining a blank in a polygonal die,

spreading the blank into the die by partially piercing the same from at least one end surface while leaving part of that end surface unconfined in .an axial direction and leaving a web of metal in the blank in alignment with the pierced hole. flowing the metal of the web by exerting pressure thereagainst from one end face of the blank with that end face and the opposite side of the web unconfined in an axial direction and punching out the web to form an axial opening through the blank.

30. The process of making nuts by cold working including confining a blank in a polygonal die, upsetting the blank into the die by piercing the same from one end face through more than half the axial length of the pierced blank with a part of that end face unconfined in an axial direction leaving a web of metal in the blank in alignment with the pierced hole, flowing the metal of the web and further upsetting the blank by exerting pressure against the web from the opposite end face of the blank with both that end face and the opposite side of the web unconfined in an axial direction and punching out the web to form an axial opening through the blank.

31. The process of making nuts by cold working including piercing a blank from one end face through more than half the axial length of the pierced blank with a. part of that end face unconfined leaving a web of metal in the blank in alignment with the pierced hole, flowing the metal of the web by exerting pressure thereagainst from the opposite end face of the blank only while leaving a part of that end face unconfined, shaping the end faces of the blank by exerting pressure against the same while leaving at least a portion of the pierced hole unconfined to permit a fiow of metal into the pierced hole and punching out the metal of the web and any excess fiow into the pierced hole to form an axial opening through the blank.

32. The process of making nuts by cold working including simultaneously piercing a blank from the opposite end faces to upset the blank into a polygonal die leaving a web of metal between the pierced holes, flowing the web of metal b exerting a pressure thereagainst from one side with the opposite side unconfined, and punching out the web to form an axial hole through the blank.

33. The process of making nuts by cold working including simultaneously piercing a blank,from the opposite end surfaces to upset the metal into a polygonal die and extending one piercing action through a substantially greater axial length than the other, leaving a web of metal positioned within the blank between the pierced holes, flowing the metal of the web by exerting a pressure thereagainst from one side with the opposite side unconfined and punching out the metal of the web to form an axial hole through the blank.

34. The process of making nuts by cold working including upsetting a substantially cylindrical blank into the confines of a polygonal die by axial piercing, forming at least one pierced hole in the blank, shaping the end face of the blank by exerting a pressure thereagainst with at least a portion of the pierced hole unconfined internally to permit a flow of metal into the pierced hole and forming an axial opening through the blank by punching out the metal therein including any excess metal which has flowed into the pierced hole.

35. The process of making nuts by cold working including confining a substantially cylindrical blank in a polygonal die, upsetting the blank into the die by axial piercing from at least one end face of the blank while leaving a part of that end face unconfined in an axial direction, shaping the end faces of the blank by exerting a pressure thereagainst with at least a portion of the pierced hole unconfined internally to permit a fiow of metal into the hole, and finally punching out an axial opening to theblank.

36. The process of making nuts by cold working including confining a blank in a polygonal die, upsetting the blank into the die by partially piercing the blank axially from the opposite ends and extending the piercing operation from one end through more than half the axial length of the pierced blank while leaving said one end unconfined in an axial direction over an ,area radially outward of the piercing tool and subsequently finishing said one end face by withdrawing the piercing tool and exerting a pressure against said end face.

37. The process of making nuts by cold working including confining a relatively rough and unsized blank in a polygonal die, upsetting the blank into the die by piercing the same from at least one end face to a predetermined depth to cause the excess metal to fiow axially around the piercing tool, and finishing at least said one end face and reducing the blank to the desired axial length by exerting pressure on the end faces with the pierced hole unconfined to 1permit the excess metal to fiow into the pierced 38. The process of making nuts by cold working including confining a relatively rough and unsized blank in a polygonaldie, upsetting the blank into the die by piercing the same from at least one end face to a predetermined depth to cause the excess metal to fiow axially around the piercing tool, and finishing at least said one end face and reducing the blank to the desired axial length by exerting pressure on the end faces with the pierced hole unconfined to permit the excess metal to fiow into the pierced hole, and forming an axial opening through the blank of the desired size by punching the blank axially and removing the excess metal which has flowed into the pierced hole.

39. In the manufacture of nuts by cold working the process including confining a pierced unfinished blank in a die, exerting pressure on the end faces of the blank with at least a portion of the metal defining the pierced hole unconfined to permit a flow of metal into the pierced hole and without relieving such pressure punching the blank axially to form an opening therethrough.

40. In the manufacture of nuts by cold working the process including upsetting a blank by partially piercing the same from at least one end surface while leaving a. part of such end surface unconfined in an axial direction, exerting pressure on the end faces of the blank while the blank is confined externally and the pierced hole is at least partially unconfined, and without removing such pressure punching the blank axially to form an opening therethrough.

41. The process of making nuts by cold working comprising upsetting a blank into a polygonal die by piercing the same from the opposite end faces simultaneously, exerting pressure "on the opposite end faces of the blank while the blank is confined externally and at least a portion of a pierced hole is unconfined to permit a flow of metal'into su'ch pierced hole and without relieving such pressure punching the blank axially to form an opening therethrough.

42. The process of making nuts by cold working including confining a blank in a polygonal die, upsetting the blank into the die by P rtially piercing the same to a greater depth on one side than on the other while leaving the surface on the more deeply pierced side with its end face radially outward of the pierced tool unconfined in an axial direction leaving a web of metal in theblank in alignment with the pierced hole, flowing the metal of the web by exerting pressure thereagainst from the opposite end face of the blank only while leaving that end face unconfined in an axial direction over an area radially outward of the pressure tool, shaping a portion of the end faces of the blank .by exerting pressure against the same while leaving at least a portion of the pierced hole unconfined to permit a flow of metal into the pierced hole and punching out the metal of the web and any excess flow into the pierced hole to form an axial opening through the blank.

,43. The process of making nuts by cold work-- ing including the chamfering of an end surface of a cylindrical blank, upsetting said blank into the confines of a polygonal die by axial piercing for more than half the length of the blank to fiow the chamfer of the cylinder into the corners of the die, shaping the end face of the blank by exerting pressure thereagainst with at least a portion of the pierced hole unconfined internally to permit a flow of metal into'the pierced hole and formingan axial opening through the blank by punching out the metal therein including any excess metal which has flowed into the pierced hole.

WILLIAM L. CLOUSE.