Abstract: A method is provided, which comprises the following steps: Firstly, a profiled material of aluminum is prepared. Then, a profiled piece of predetermined length is produced by cutting the profiled material to length. This profiled piece is then inserted into a press. Finally, the profiled piece is pressed into the desired shape in the press. Further, a shaped part is provided, which consists of cold-worked aluminum.

Abstract: A method for forming a groove by plastic deformation to provide improved working efficiency. A hole 4 having a diameter larger than a width W of a desired groove 6 and a depth deeper than the desired depth of the groove 6 is formed in an end face 2 of a rod 1. Subsequently, the groove 6 is formed by plastic deformation to partially overlap the hole 4. The plastic working to form the groove may be carried without the use of a die.

Abstract: A forging die apparatus comprises a punch for applying a pressurizing force to a forging material arranged in a cavity, a cylindrical member installed to surround a part of outer circumference of the punch, for making displacement integrally with the punch, and a first ring member formed with a hole for forcibly inserting the cylindrical member therein when the punch applies the pressurizing force to the forging material.

Abstract: A female die and a punch for forming relatively complex parts from axi-symmetrical workpieces, and the method of using the female die and punch to form the parts from the workpieces are disclosed. The female die and punch are used in a forging apparatus to near net warm forge parts that include curved surfaces with at least one protrusion offset from the longitudinal central axis of the part, or other complex part configuration. The female die includes curved inner surfaces that form the curved surfaces on the part and a recess to form the protrusion. The punch includes a forming surface at the bottom that is shaped to move material of the workpiece into regions of the cavity that form the protrusion. The volume of the part is substantially equal to the volume of the workpiece.

Abstract: A female die of a closed die set for use in near net warm forging a part includes a cavity having a tapered upper portion and a lower portion. The upper portion is configured to support a workpiece at a preliminary position in the cavity, and to cause the workpiece to be pre-bent as it is moved through the upper portion of the cavity by a punch. The lower portion has a constant length and width so that the workpiece remains in the pre-bent shape during movement through the lower portion to the bottom end of the cavity. The workpiece is finally formed at the bottom end of the cavity to produce the part.

Abstract: A method and an apparatus for producing a disc product having a plane carng a relief and helical ridges on the outer peripheral side. The inventive production method and the apparatus therefor have enabled a continuous processing of a material mass to forge into, produce and push out a disc product while retaining the quality of the relief plane, and thereby facilitating production of the disc product by die forging.

Abstract: The present invention relates to a method of forming an inner flange on a sheet metal member having a cylindrical portion with an inner flange 3 required in coupling of a shaft such as a pulley used in an automobile. The axial length of a boss formed on the sheet metal member is reduced by pressing the boss in the axial direction of the boss, and an excess portion produced as a result of the reduction of the axial length of the boss is gathered in one place in the axial direction of the boss, for example, the end in the axial direction of the boss to project inwardly into the inside of the boss, so that the inner flange is formed by the projected excess portion. A step of gathering the excess portion produced as a result of the reduction of the axial length of the boss can be conducted by a pressing process in which a pressing die is moved in the axial direction of the boss.

Abstract: A female die of a closed die set and a punch for near net warm forging complex shaped parts such as lugs from axi-symmetrical workpieces are disclosed. The punch includes a bottom forming surface having opposed chamfer surfaces which move workpiece material laterally in the cavity, prior to and during warm forging, such that the die cavity is substantially evenly filled. Consequently, the resulting parts are evenly filled without requiring that the workpieces fit snugly in the die cavity.

Abstract: An apparatus for forming a slot in a semi-product of a bolt prior to thread formation includes a punch and a die mechanism. The die mechanism includes a tubular member, and an elongated die member formed integrally with a slot-forming plate which is located at a front end portion thereof and which has a uniform-thickness flat middle portion and two side portions that are wider than the middle portion. The semi-product can be compressed between the punch and the slot-forming plate of the die member in a central bore in a high-hardness block, which is fixed in the tubular member, to form the slot. Accordingly, the slot has a uniform-width middle portion and two end portions which are wider than the uniform-width middle portion. When threads are formed on the semi-product by means of a lathe, no projections are created in the uniform-width middle portion of the slot, thereby permitting a wedge-shaped end of a screwdriver to engage fittingly the uniform-width middle portion of the slot.

Abstract: An axially symmetric ring work piece is formed by a warm or hot, forward and backward extruding, die forging system. In this system, a die having a rearwardly projecting portion, which projects in the opposite direction to a pressing direction, a heated work piece, and a punch having a forwardly projecting portion, are arranged, in that order, in a container. A withdrawal die is arranged between the container, and the heated work piece, the die and the punch. The die is fixed so that a die velocity V.sub.D is 0, and the punch is moved toward the die while a punch velocity V.sub.P is set to be twice as large as a withdrawal die velocity V.sub.WD and the strokes of slide of the withdrawal die are not less than one-half of a forward-extruded foot length of a product. Thus, the forward and backward simultaneous extrusion can be substantially performed in a single-action type, short-stroke, die forging system.

Abstract: A method for forming a high-tooth spline of a hollow shaft which comprises a step of press-inserting a workpiece of a hollow shaft into a die having a spline-shaped internal surface by a punch, for backing up a portion of the workpiece corresponding to the spline-shaped surface of the die from the inside thereof, having a tip portion made of a material having a hardness lower than that of the die, and a step of forming a spline portion on the workpiece. A hollow shaft having a high-tooth spline formed by the above method.

Abstract: A method for manufacturing a cap for use in a semiconductor package is disclosed. The semiconductor package includes a semiconductor chip and a substrate. The chip is mounted with the substrate at a chip locus. The method preferably comprises the steps of placing a slug in a die, and exercising the die to cold flow the slug to a predetermined cap configuration. The cap configuration includes a plurality of walls depending from a polygonal generally planar base and cooperating with the base to establish a well bounded by the walls and the base. The walls terminate in a plane, and the well clears the chip when the cap is mounted on the substrate at the chip locus. The invention further includes a cap for use in a semiconductor package. The cap comprises a structure cold flowed from a slug in a die to a predetermined cap configuration.

Abstract: Method for forming a double cylindrical pulley, in which a work piece placed in a die is pressed by a punch to cause the work piece to make a plastic deformation, for forming an inner ring and an outer ring of the pulley to have the same hardnesses and lengths, and a device suitable for forming the same, is disclosed, the method including: the steps of placing a piece of raw material on a counter punch mounted in a die of a built up metal mold; and, lowering a punch onto the piece of raw material, whereby the piece of raw material is caused to make a plastic deformation so that the piece of raw material flows into spaces between the die and counter punch to form an inner ring part and an outer ring part, and a flow of the material toward the outer ring part is controlled by a step part formed on the die to form an extended tip part, and the inner ring part and the outer ring part to have the same lengths and hardness: and the device including a die for placing a piece of raw material thereon; a counter punch

Abstract: An improved screw washer, and an improved mold for fabricating the improved screw washer. Using a selected metal plate having a thickness thinner than a nominal height demanded for a nut, the invention primarily aims to form an improved screw washer incorporating a nut satisfying the demanded height. The invention is to provide an improved screw washer, and an improved mold for fabricating the screw washer. Particularly, using this improved mold, the improved screw washer can easily be manufactured, where the above-identified nut is solidly bonded with the metal plate without being disengageable therefrom, and yet, a sufficiently lengthy tapped hole is formed. Structurally, a nut is formed in the state of being continuous to a metal plate after punching out part of the metal plate.

Abstract: A method of manufacturing a one piece integral metallic beam (22) having flanges (24), and a web (26) joining said flanges, the beam having been hot rolled from a heated metal workpiece (20) to produce an integral one piece beam having flanges and a web extending therebetween, the flanges having a predetermined first thickness, and the web having a predetermined second thickness less than the first thickness, and in which the web is heated to a hot forming temperature, without substantially heating the flanges and, the web is than passed through at least one metal forming die set (16), which is repeatedly closed on the web to form the web without forming the flanges. The method may also include the piercing of openings (28) through the web, and the forming of lips (30) around the openings, and also, the forming of a secondary product (52) from the portion of the web discarded from the opening, and also hot forging the lips (30) around the openings.

Abstract: A pressure-receiving plate for a friction device includes an annular portion and pawls formed integrally on the inner or outer periphery of the annular portion. The annular portion has one side provided with a friction surface which contacts a friction disk engaged with one of a driving member and a driven member, and another side provided with reduced-thickness portions formed by applying crushing work that takes hardness and surface roughness of the friction surface into consideration. The pawls are engaged with the other of the driving member and driven member.

Abstract: A process and apparatus for cold extruding gear teeth and projections comprises machining an annular ring gear blank with precision inside and outside diameters. The gear blank is mounted on a die ring which is arranged coaxially with respect to the blank. The die ring has internal die teeth. A mandrel having external die teeth is axially aligned with the gear blank. The mandrel or die ring is moved axially to extrude the blank through the internal and external die teeth.

Abstract: An outer-ring of a constant velocity joint is fabricated by pressing an inner surface of the pre-processed outer-ring (2A) set in a lower die (3) by using a forging punch (20) in which plural punch pieces (11) each having a protrusion (111) corresponding to the ball track groove (6) are slidably coupled to plural downwardly tapered grooves (131) of a punch piece slide member (13), so that an upper periphery (9A) of the pre-processed outer-ring (2A) is contracted in line with a head shape of the forging punch (20), and ascending the forging punch.

Abstract: A method of making the ejector tubes which serve to guide the ejectors used in molds, for example those used in injection molding comprises a series of operating stages performed on a tube which is the starting point. The first stage is the cutting of a length of the tube to the desired length, with diameter oversizing to allow for subsequent truing. The second stage involves reducing the diameter at one of the end sections. The third stage consists of pretruing the outside, the fourth stage being machining the inside of the end section with total concentricity. The fifth stage involves induction treatment, and this is followed by the sixth stage which is the truing of the outside to obtain the desired outside diameter. In the seventh stage the inside diameter of section is trued, and then finally, in the eighth stage the front section is refaced, thus obtaining an ejector tube for moulds in general. Optionally, a butt may be formed on the rear end of the tube.

Abstract: Precision forming apparatus is disclosed. The apparatus comprises a die with a cavity which conforms with the shape of a portion of a part to be formed, a punch with a cavity which conforms with the shape of another portion of the part to be formed, and means for causing relative movement of the die and the punch between(a) a first (closed) position in which the die and the punch nearly abut one another and the two cavities are aligned and form a single cavity which conforms with the shape of the part to be formed, andb) a second (open) position in which the die and the punch are separated from one another and a billet can be placed in the cavity of one to be formed, when the two are returned to the first position, to the shape of the single cavity.The cavity forms longitudinally opposed end walls in their entirety. As a consequence, the length of a part to be formed is determined by the punch cavity, and can be changed by substituting a different punch.

Abstract: The periphery of a workpiece which has already been subjected to burring is at least partially punched by a periphery punch and a periphery die. The burred portion is then further pressed by the periphery punch and a die surface including an annular portion which opposes the periphery punch while restricting the lateral movement of the workpiece by the periphery die. An apparatus for working a burred portion is made up of a metallic mold having a periphery die and a periphery punch, a lifter which is disposed inside the periphery die so as to be movable up and down relative to the periphery die, and further working device for further working the burred portion into a shape and dimension of those of a final product of the workpiece. The further working device includes a pilot pin which is projectingly fixed to a lower end of the periphery punch and a knockout which is disposed in a recess in the lifter and which has an annular portion on its upper edge.

Abstract: A wirebond probe head is modified for use in forming raised portions from material. The modified head includes a main portion and a sleeve, with the sleeve functioning as a shroud to reduce the tendency of forged material to exude from the periphery of the wirebond probe. The sleeve may also be vibrationally isolated from the main portion of the head in order to attenuate vibrational energy transferred from the main portion of the head to the sleeve. The inventive head functions by being brought into close proximity to a surface material and applying energy. This results in an ultrasonically formed elevated surface irregularity, or an ultrasonic forging splash, which useful as an electrical contact pad for permanent and semipermanent electrical connections.

Abstract: Disclosed is a method of forming a shaped configuration by cold forging at an end of a long element, such as the armature shaft of a starter motor for an automobile. The die used in this method has an inner space in which a section for forming the shaped configuration is provided at one end portion thereof, and the diameter of the inner space gradually increases from the shaped configuration forming section to the other end portion of the inner space. A material is placed in the die from the other end portion of the inner space and, then, is forced into the die by a punch to be forged into the shape corresponding to that of the inner space of the die. After the forging, the shaped material is pushed out of the die by a knock-out pin which is inserted into the die in the opposite direction to the direction in which the material is forced.

Abstract: This invention pertains to an apparatus for producing ellipsoid forms from an expanded metal net. The apparatus includes a first frame defining a path of travel for a continuous sheet of slitted metal foil, an input feed roller for holding the continuous sheet of slitted metal foil in roll form, multiple work stations located on the frame, and forming pistons which cooperate with forming cylinders to shape cut expanded metal foil into an ellipsoid configuration.

Abstract: This invention relates to a forming machine used for full enclosed die forming etc. The forming machine of this invention consists of inserting a punch into at least one of a pair of dies disposed to face each other, supporting the die having the punch inserted therein by one end of a ring member accommodated in a holder, and disposing the other end of the ring member within a cylinder chamber formed within the holder; the above ring member has a piston member disposed within it, the above punch is supported by one end of the piston member, and the other end of the piston member is disposed in the above cylinder chamber formed within the holder or a cylinder chamber communicated with the holder.

Abstract: A method is disclosed of externally and internally upsetting the end of a steel tube to provide a thicker wall for welding to a tool joint and for providing an internal tapered section having a projected length (Miu) along the longitudinal axis of the tube that substantially exceeds today's API standard upset. The method includes three upsetting steps, one pressing step, and one reheating step after the first two steps of the method.

Abstract: An outside ring manufacturing method comprises a first step of blanking out from a metal sheet a blank with a circular body portion and tongue portions which protrude at several places from the outer peripheral edge of this body portion, a second step of press forming the blank so that the body portion is formed into a tapered cylinder portion which tapers off or decreases in diameter with the distance away from the tongue portions and so that the tongue portions are made parallel to an axis of the tapered cylinder portion, a third step of adjusting the geometry of each part to a predetermined geometry through the machining of an end surface of the tapered cylinder portion and the tongue portions, and a fourth step of heat treatment to achieve a desired hardness.

Abstract: A press device which is reduced in overall height thereof and in deformation of a press frame and can sufficiently support an eccentric load thereto. The press device comprises a press force generating unit disposed in a press frame and including a lid member secured to the press frame, a cross head having a cylinder chamber in which the lid member is fitted for axial sliding movement and having a blank holder at an end face thereof remote from the lid member, and a pressurizing member fitted for axial sliding movement in a portion of the cylinder chamber remote from the lid member. A shaping element is disposed in the press frame in an opposing relationship to the press force generating unit and has a shaping portion in which the pressurizing member is fitted.

Abstract: For use in the making of coins a laminated composite is proposed which can be used to substitute coins made of nickel and consists of a combination of a ferritic chromium steel and an austenitic nickel-chromium steel. In dependence of the nature of the existing system used to discriminate the nickel coins to be substituted, a laminated composite may be used which has a core layer consisting of the ferritic chromium steel and provided on both sides with a cladding having a thickness of 2 to 10% of the total thickness and consisting of the austenitic nickel-chromium steel, or a laminated composite which comprises a core layer consisting of the austenitic nickel-chromium steel and provided on both sides with a cladding having a thickness of 20 to 40% of the total thickness and consisting of the ferritic chromium steel. An optimum approxmation of the acceptability ranges adjusted for nickel in the discriminating systems can be achieved by a proper selection of the ratios of the thicknesses of the layers.

Abstract: A closed-die forging having an annular flat surface portion and a corner portion at an outer periphery of the annular flat surface portion is made by a method consisting of a rough forging process and a finish forging process. In the rough forging process, a rough forged product is shaped so as to have an annular flat surface portion smaller in outer diameter than the first mentioned annular flat surface portion and a conical surface portion at an outer periphery of the second mentioned annular flat surface portion. The conical surface portion is so shaped as to extend increasingly outwards as it extend in the same direction of movement of a punch of a rough forging die for performing a forming operation.

Abstract: Progressive step and compound dies are employed in a cold working process to form a metallic preform of selected mass into a precision-finished, pore-free, annular bushing with a mass substantially equal to that of the preform for use as a battery terminal which allows the fracture free spin over connection of the stem of the bushing to a battery cover and the close fit of the bushing on the battery post when the cover is fitted to the battery casing.

Abstract: In apparatus according to the present invention, re-forming takes place in a single operation. The forming device contains a die extended by a hollow cylindrical die area and includes a punch which is surrounded by an outer punch which is advanced under the tension of a spring and fits into the hollow cylindrical die area. A conical centering area is located upstream of the hollow cylindrical die area. Used spot welding electrodes of different lengths and pronounced deformation can be restored several times with this forming tool.

Abstract: A process, apparatus and alloy for net forming intricate metallic shapes. A fixed die (30) is mounted in a forging press (20). The die (30) has a cavity (45) at least the proximal end (62) of which is open to receive a ram (55). The cavity (45) is contoured to the shape of the finished article to be forged therein, and a metallic slug (50) is receivable within the cavity (45). The ram (55) is driven into the proximal end (62) of the cavity (45) against the proximal end (63) of the slug (50) under selected pressure and temperature and for a selected period of time. The slug (55) is thereby forged into close conformity with the contours of the cavity (45), the formation of the slug (50) being accomplished first at the distal end (64) of the slug and thereafter being progressively initiated and completed toward and proximal end (63) thereof.

Abstract: A method of making terminal nut for ignition plug by plastic working, comprising; first step in which a metallic blank is struck at its end surfaces to flatten the end surfaces in prependicular to axial direction of the blank; second step in which a central conical dent is formed at one end surface of the blank, and forming first bottom-ended hole at other end surface of the blank; third step in which second bottom-ended hole is formed concentrically and continuously from the first bottom-ended hole at the blank to be diametrically lesser than the first bottom-ended hole; fourth step in which the blank is axially contracted to diametrically bulge outward by upsetting; fifth step in which a perforation hole is axially formed at the blank by punching in concentrical relationship with the first bottom-ended hole; sixth step in which the blank is shaved at its bulged portion.

Abstract: During the forging step two metallic flows are generated in the metallic blank, one is an elongating flow toward the flange portion and another is an elongating flow toward the cylindrical portion. These metallic flow are generated simultaneously.Since the metallic blank elongates toward the cylindrical portion and the flange portion at the same time, the metallic structure of the product formed by the present forging method does not develop a slide surface, so that no weak portion is generated in the product.

Abstract: Press tooling for manufacturing an inner or outer member of a constant velocity universal joint, with non-undercut ball-receiving tracks and, between such tracks, a part-spherical cage guiding surface, comprises a first element with radially extending ribs for forming the tracks, and a number of second elements with portions which fit between the ribs of the first element and are shaped to form the part-spherical surface of the joint member between its tracks. For forming an outer joint member the first element may have outwardly extending ribs between which the second elements fit, or for forming an inner joint member for first element may be in the form of a sleeve with inwardly extending ribs between which the second elements fit.

Abstract: A method of manufacturing a substrate for a memory disk characterized in that a blank material comprising a non-magnetic metal substrate covered with a non-magnetic metal as an underlayer is subjected to a coining operation by two dies, i.e. upper and lower dies each having flat compressing surface and a certain kind of textured design formed thereon within an apparatus including a mandrel and a die ring arranged to limit the spreading extent of the material whereby a surface having ultra-preciseness and simultaneously impressed texture design is obtained.

Abstract: A method for manufacturing a metal substrate for a memory disk wherein a metal blank material (6) is sandwiched between two dies within a metal mould (3) limiting the extent to which the material spreads, using a core member (4) if necessary, each of the dies having a flat and smooth working surface, the compression force and sheet gauge reduction ratio being regulated or the surface roughness and amount of coating lubricants employed being regulated.

Abstract: A method of manufacturing a substrate for a memory disk characterized in that a blank material comprising a non-magnetic metal substrate covered with a non-magnetic metal as an underlayer is subjected to a coining operation by two dies having flat compressing surfaces within an apparatus including a mandrel and a die ring arranged to limit the spreading extent of the material whereby a surface having ultra-preciseness is obtained.

Abstract: A method and apparatus are disclosed for forging a wrenching socket in the end of a fastener which permit the production of such fasteners from materials which are difficult to forge, such as titanium and some high strength steels. A cylindrical preliminary socket is formed in the end of the blank forming the fastener with a punch having a circular cross section. The preliminary socket is sized to be at least as great as the maximum lateral dimension of the finished wrenching socket required. Subsequently, a tool having a cross-sectional shape corresponding to the required finished socket is positioned in the preliminary socket and the material of the blank is extruded inwardly against the tool to form a cylindrical exterior surface and a finished socket having a non-circular cross section. With this invention, even very small hexagonal sockets can be formed in titanium fasteners.

Abstract: The present invention relates to a spur gear automatic production process wherein spur gears are cold-press formed. The invention provides a top and bottom table with stock fed therebetween in sequential operation with the vertical stroke of the press machine, stamping a disk-shaped gear workpiece by means of top and bottom die sets in the first section which are positioned for integrated movement, thereafter moving said gear workpiece to the second section by means of an unobstructed feed, stamping thereon the tooth profile by means of the vertical stroke of top and bottom die sets positioned in said second section, and ironing said gear workpiece in the reverse direction to the stamping process.

Abstract: An accumulator system for establishing a clamping force on dies in a closed die forging device. The accumulator system includes an accumulator having a differential piston and a free piston. The small end of the differential piston forms a wall of the accumulator oil chamber hydraulically connected to variable volume oil chambers behind the dies. The big end of the differential piston and one side of the free piston form a low pressure gas chamber of the accumulator. The other side of the free piston forms a wall of a high pressure gas chamber of the accumulator. As the dies of the forging apparatus close, oil in the chambers behind the dies moves the differential piston against only the gas pressure in the low pressure gas chamber so that closure is essentially without impact.

Abstract: The present invention relates to a process for the manufacture of parts having a tooth profile and boss by means of a press machine. The process of the present invention comprises a blank with a boss, which is produced in a prior operation by machining, cold forging, warm forging or other method, being positioned on a female die having a tooth profile formed thereon on a mirrored surface, said female die having a 20.degree.-150.degree. taper at its inlet, and having a shape conforming to the bottom configuration of said blank, and wherein an ironing process is performed by means of a punch having a shape conforming to the top configuration of said blank.

Abstract: A friction ring for clutches and brakes consists of an annular metal element having at least one cylindrical or conical friction surface comprising a spray-sintered friction lining. The friction linings are directly sintered onto the annular element itself, the intially planar friction surfaces being formed, after applying the spray-sintered friction linings, into cylindrical or conical shape by a non-cutting shaping process such as stamping, deepdrawing or the like. The method of producing the friction ring comprises producing an annular metal element, applying a spray-sintered friction lining on to one or both sides thereof and shaping the annular element together with the sintered linings applied thereto into a cylindrical or conical form. The shaping is performed by means of a shaping tool comprising a die and an associated plunger working on the annular element.

Abstract: A tool for the manufacture of the outer member of a cross groove type constant velocity ratio universal joint has two sets of first and second elements disposed circumferentially between one another about the axis of the tool with the elements having portions which interfit to define a surface whose shape corresponds to that required in the joint, the portions having formations which form the sets of grooves, and with the elements so shaped that portions of the first elements can be moved radially inwardly to disengage their formations from the grooves.

Abstract: A cup-shaped raw workpiece having a bottom panel and a cylindrically-shaped circumferential panel is positioned facing downwardly on a movable lower punch having a forming gear profile. The lower punch is provided in a die having an orifice portion which together with the gear profile defines an orifice. A resilient mechanism resists downward movement of the lower punch. An upper punch is lowered to hold the bottom panel of the workpiece against the lower punch and pushes the workpiece to extrusion form the inner surface thereof through the orifice. An escape groove for excess metal can be provided in the bottom inside corner of the workpiece at the juncture of the circumferential panel and the bottom panel. The lower punch can be provided with an upwardly extending protrusion near the outer circumferential edge of the upper end surface thereof which has an outer chamfered circumferential edge.

Abstract: A method of manufacturing a scroll member for use in a rotary compressor has the steps of heating a material which has been preformed into a substantially frusta-conical body consisting of a flat upper surface portion provided with a cylindrical projection integrally formed in the center portion thereof and a lower surface portion having a conical surface and a flat projecting surface, and forging the material by a forging apparatus. The heating step compriss a first heating at a temperature in the range from 100.degree. to 200.degree. C. and a second heating at a temperature of 440.degree. C. which is carried out after coating the material with graphite, the coating being applied to the material between the first and the second heatings.

Abstract: A method of forming a countersink around a hole in a metal plate. A stepped punch is pressed, stem first into the hole, with such a force and at such a rate as to cause deformation but not shearing of the metal, there being an annular ring of unrestrained surface around the hole at the backside of the plate. The resulting countersink has cold-worked surfaces, and a raised ring is formed on the backside of the plate.

Abstract: The present invention provides an apparatus for producing in a single stroke a forged metal article with a helical contoured surface. The apparatus uses an upper punch with a generally smooth surface which is telescopically received in a punch housing and a lower punch of generally smooth surface which is mounted for free rotation with respect to the axis of the die assembly. This design allows for the use of a die of the general configuration and length of the finished article which is economical and efficient to operate.

Abstract: This invention relates to a method of manufacturing an ignition file for a lighter by a press and a device therefor, more particularly to an improvement of a punching operation of an axial hole for mounting an ignition file. A material pressed into a disk-like configuration is prepared and a concave portion is provided in the approximate center of both sides of the file member. A hole is punched between concave portion having a diameter smaller than that of the concave portion. The fin of the file member caused by punching is absorbed in a gap provided inside the die wall while the fin projecting toward the die hole to be punched is absorbed in said concave portion.