US3555586A - Forging machine - Google Patents

Abstract

A COMBINED MACHINE IS DISCLOSED FOR FORMING THREADED ARTICLES FROM ROD OR WIRE STOCK. THE MACHINE INCLUDES A PROGRESSIVE HEADER OPERABLE TO UPSET BLANKS AND A RECIPROCATING THREAD ROLLER OPERABLE TO THREAD THE BLANKS. THE HEADER INCLUDES A CRANK AND PITMAN DRIVEN RECIPROCATING SLIDE AND THE THREADER INCLUDES A CRANK AND PITMAN DRIVEN THREAD ROLLING SLIDE. A RECIPROCATING BALANCING MASS IS PROVIDED ON THE MACHINE ON THE SIDE OPPOSITE FROM THE THREAD ROLLING SLIDE. THE DRIVES FOR THE FORMING SLIDE, THREAD ROLLING SLIDE, AND RECIPROCATING MASS ARE ARRANGED SO THAT THE THREAD ROLLING SLIDE AND RECIPROCATING MASS COOPERATE TO PROVIDE SUBSTANTIALLY COMPLETE DYNAMIC BALANCE OF THE ACCELERATION FORCES OF THE FORMING SLIDE. THE CRANK SHAFT IS PROVIDED WITH ROTATING ECCENTRIC MASSES ARRANGED SO THAT THE ROTATING MASSES ARE ALSO DYNAMICALLY BALANCED TO A SUBSTANTIAL EXTENT. BECAUSE SUBSTANTIALLY COMPLETE DYNAMIC BALANCING IS PROVIDED, THE MACHINE MAY OPERATE AT HIGHER SPEEDS WITHOUT DAMAGING VIBRATION.

Description

Jan. 19, 1971` R. E. WISEBAKER i 5 Y351555,586

FORGING MACHINE v Filed Nov. 29, 1968 4 Sheets-5heet l /NVENTO/P Jan. y19, 1971 R. E. wlsEBAKER 3,555,58-64 FORGING MAHIN Filed NQvQzQ, 196s 4 sheets-sheet 2 Jan 19,1971 R. E. WISEBMQERv l 3,555,5864

FORGING MACHINE 4 Sheets-Sheet 5 Filed NQv.` 29, 1968 Jan. 19, 1971 R. E. wlsEBAKER v3,555,586

FORGING MACHINE Filed Nov. 29, lees 4 sheets-sheet 4 United States Patent Oliice 3,555,586 Patented Jan. 19, 1971 ABSTRACT OF THE DISCLOSURE A combined machine is disclosed for forming threaded articles from rod or wire stock. The machine includes a progressive header operable to upset blanks and a reciprocating thread roller operable to thread the blanks. The header includes a crank and pitman driven reciprocating slide and the threader includes a crank and pitman driven thread rolling slide. A reciprocating balancing mass is provided on the machine on the side opposite from the thread rolling slide. The drives for the forming slide, thread rolling slide, and reciprocating mass are arranged so that the thread rolling slide and reciprocating mass cooperate to provide substantially complete dynamic balance of the acceleration forces of the forming slide. The crank shaft is provided with rotating eccentric masses arranged so that the rotating masses are also dynamically balanced to a substantially extent. Because substantially complete dynamic balancing is provided, the machine may operate at higher speeds without damaging vibration.

BACKGROUND OF INVENTION 'This invention relates generally to automatic forging machines for forming threaded articles such as bolts, screws, and the like, and more particularly to a novel and improved machine of this type which is capable of operating at high speeds without damaging vibration.

PRIOR ART `Combined machines for forming bolts, screws, and the like are well known. Such machines often include a progressive header which operates to progressively form a blank, and a roll threader which subsequently threads the blank to form the finished article. An example of such machine is described in the U.S. Letters Patent 2,020,65 8 dated Nov. 12, 1935. Other known machines combine a multiple blow header, such as a double blow header, with a threader. Here again, the header forms a blank which is subsequently threaded to form the desired article. A11 example of such a machine is described in the U.S. Letters Patent 3,116,499 dated Jan. 7, 1964.

In both types of machines a forming slide is driven for reciprocation by a rotating crank shaft through a crank and pitman mechanism. Therefore, there are two categories of acceleration forces which must be balanced to a sufficient degree to permit operation at the desired speed. The rst category includes the forces produced by eccentric masses moving with rotary motion and the second category includes the forces produced by the reciprocating masses.

In the past it has been customary n many instances to provide rotating eccentric masses which are sized and positioned to provide some dynamic balance of the reciprocating mass. Since the motion of such balancing mass is dilferent from the motion of the reciprocating mass, such balancing systems cannot provide a truly dynamically balanced machine. Therefore, such machines have been provided with large massive frames which are able to absorb the imbalance to a sufficient degree to prevent damaging vibration. These machines function well, but cannot be operated practically at higher speeds.

In some machines, which are intended for high-speed operation, separate balancing masses, which move in a reciprocating manner, have been provided to separately balance the reciprocating mass of the slide. Such machines provide more complete dynamic balancing and are, therefore, capable of operating at higher speeds without requiring the use of excessively large frames or the like. However, they do require additional mechanism to supply the support and drive for the separate balancing masses.

SUMMARY OF THE IINVENTION The present invention is directed to a novel and improved combined machine for forming threaded articles wherein simplified means are employed to provide dynamic balancing so that the machine can operate at higher speeds. In the illustrated embodiment there are two reciprocating slides, a header slide and a threader slide. The two slides are located and driven so that each slide provides at least a part of the dynamic balancing of the other side. The machine provides suflicient dynamic balancing to permit high-speed operation without destructive vibration and accomplishes at least part of the balancing by the use of mechanisms that also have operation functions in the machine.

The use of the threader slide to provide at least part of the dynamic balancing of the forming slide simplifies the machine since, in most instances, it eliminates the need of at least one reciprocating balancing mass having only a balancing function. Similarly the use of a forming slide to provide dynamic balancing of the threader slide provides the desired balancing function without requiring a separate balancing mass to balance the threader slide. A machine incorporating this invention includes sufficiently complete dynamic balancing to permit highspeed operation of the machine and provides a structure which is relatively simple and dependable.

DESCRIPTION OF THE DRAWINGS FIG. 1 is a side elevation of a combined machine incorporating this invention illustrating the threader side thereof;

FIG. 2 is a plan view of the machine illustrated in FIG. 1 with certain parts of the machine eliminated for purposes of simplification;

FIG. 3 is a side elevation of the machine illustrated in FIGS. 1 and 2 illustrating the side opposite the side illustrated in FIG. l; and,

FIG. 4 is a schematic fragmentary perspective view of the slide and drive mechanism of the machine.

Referring to FIGS. 1 through 3,` the illustrated machine is particularly adapted for the manufacture of bolts, screws, and the like. The machine includes a frame 10 adapted to support the entire machine. Journaled on the frame 10 is a main crank shaft 11 which is provided with a fly wheel 12 at one end. A motor 13 is connected through drive belts 14 to the fly wheel 12 to rotate the crank shaft 111.

The crank shaft 11 -is connected through a pitman 16 to reciprocably drive a forming slide 17 which is supported on the frame 10 by planar bearings assembly 18 for longitudinal reciprocating movement toward and away from a die breast 19'. The forming slide 17 and die breast 19 are adapted to support cooperating tools and dies which are arranged to progressively form a `blank, such as a bolt blank, to its desired shape. A transfer mechanism illustrated generally at Z1 in FIGS. 1 and 3 is provided to progressively transfer the blanks to each die station so that a blank is located in each die station during each cycle of operation and a completed blank is formed during each cycle. As illustrated in FIG. 2, the machine is provided with three tool holders 22a through 22e each of which is adapted to support a forming tool. Therefore, the illustrated machine is a three die machine. it should be understood, however, that the machine incorporating this invention may be provided with a greater or lesser number of die stations.

The machine also includes a pointer mechanism, shown generally at 23, which is operable to point the blanks after the blanks are formed by the tools carried by the forming slide, and before the blanks are supplied to a roll threader assembly at 24. Reference may be made to the copending application Ser. No. 781,092, liled Dec. 4, 1968 for a complete description of a pointer mechanism which may be utilized with this'machine. The machine is also provided with a stock feed mechanism 26 and a knockout mechanism 27.

Journaled on the frame below the crank shaft 11 is an accessory drive shaft 28 which is connected by gearing 29 to rotate with the same velocity, but in the opposite direction, as the crank shaft 11. The accessory drive shaft is provided with cams which operate linkages arranged to control the operation of the blank feed mechanism of the roll threader assembly 24 and the operation of the pointer 23. Also the transfer assembly 21 is powered lby a drive shaft 31 connected to the accessory drive shaft 28 by bevel gears 32. i

The knockout mechanism is driven by a pitman 33 connected at one end to a crank on the crank shaft 11 and at the other end to a reciprocating cam shaft 34. The drive for the feed rolls 26 includes a linkage 36 partially illustrated in FIG. 3 which is powered by movement of the pitman 33. Reference may be made to the copending application Ser. No. 784,806, led Dec. 18, 1968 for a detailed description of the transfer mechanism 21 and the knockout mechanism 27.

Reference should now be made to FIG. 4 which schematically illustrates the main machine drive and the various mechanisms which provide the dynamic balancing of the machine. It should be understood that the various elements illustrated in FIG. 4 are not shown to scale and that the illustration of FIG. 4 is schematic in nature in o1 der to provide a clear illustration of a functional aspect of this invention.

The crank shaft 11 is journaled on axially spaced bearings 41 and 42 which are supported on the frame 10 and in` turn support the crank shaft for rotation about its axis of rotation 43. The forming slide 17 is located and shaped so that its mass center moves substantially along a line of action or motion 44 which is located along the longitudinal centerline of the machine substantially midway between the bearings 41 and 42. The structure is also preferably arranged so that the line of action 44 intersects and is in the same horizontal plane as the axis of rotation 43. The crank shaft 11 is provided with a centrally located eccentric portion 46 around which one end of the pitman 16 extends and which provides the main crank of the machine.

As the crank shaft 11 rotates, the rotation of the eccentric 46' from the position illustrated in FIG. 4, which is the backward dead center position, causes the forming slide 17 to be accelerated forwardly along the line of motion 44 toward the die breast and its forward dead center position. This acceleration of the slide toward the forward dead center position produces a reaction force on the crank shaft 11 tending to urge the crank shaft rearwardly with respect to the frame. As the slide 17 approaches the forward dead center position, it is decelerated by the crank shaft. This causes a force on the crank shaft in a forward direction.

If dynamic balancing means were not provided, these forces would be transmitted by the crank shaft directly to the frame through the bearings 41 and 42. Since the forming slide is relatively heavy and since the machine is intended for high-speed'opcration, excessive vibration 4 would occur in the absence of dynamic balancing of these forces.

The dynamic balancing of the forces created by the acceleration of the forming slide 17 is provided by the thread rolling slide 47 in cooperation with a reciprocating mass 48. The thread rolling slide 47 is located outboard of the bearing 41 on one side of the machine and is guided for reciprocation by opposed bearings, schematically represented at 49, mounted on the machine frame. The bearings 49 position the threader slide so that its mass center moves along a line of action or motion 51 which is parallel to the line of motion 44, but is spaced below the horizontal plane containing the axis of rotation 43 and the line of motion 44.

A balancing element or mass 48 is pivotally supported at 52 on the frame of the machine, outboard of the bearing `42., for oscillating reciprocation along an arcurate line of action or movement 53 which is laterally spaced from the line of motion 44. The mass 48 is supported by the pivot 52 on a projection 54 which extends vertically upward from the pivot so that the principal mass moves along an arcurate path 53 which has the relatively large radius when compared to the length of movement along the arc. Therefore, the movement of the mass 48 approximates linear reciprocating movement along a path horizontally aligned with the axis 44 and parallel thereto.

The crank shaft 11 is provided with an eccentric bearing portion 56 around which a pitman 57 extends to provide the reciprocating drive for the balancing mass 48'. Similarly, the threader slide 47 is connected by a pitman 58 journaled on an eccentric bearing 59' located at one end of the crank shaft 11. The crank eccentrics 56 and 59 are located with respect to the main crank eccentric 46 so that they are substantially therefrom. Therefore, the slide 47 and the reciprocating mass 48 are in substantially their forward dead center positions illustrated in FIG. 4 when the forming slide is in its rearward dead center position. Consequently, the acceleration of both the slide 47 and the reciprocating mass 48 is substantially 180 out of phase with the acceleration of the slide 17 and movement from the position illustrated in FIG. 4 causes rearward acceleration of the slide 47 and mass 48 at the same time the forming slide 17 accelerates in a forward direction.

The mass of the slide 47 cooperates with the mass of the reciprocating mass 48 to provide a substantial amount of dynamic balancing of the acceleration forces of the forming slide 17 and the balanced acceleration forces of the forming slide 17 are transmitted by the crank shaft 11 between the respective eccentric portions and are not, therefore, transmitted to the frame through the bearings 41 and 42. It is recognized that the oscillating reciprocation of the mass 48 along the arcurate path 53 does not provide perfect dynamic balancing of the linear reciprocation of the forming slide 17 along the central axis 44 but since the movement of the mass along the arc closely approximates linear motion, the dynamic balancing of the mass 48 is sufliciently complete to permit relatively highspeed operation. Similarly the slide 47 is guided for reciprocation along a line of action 51 which extends slightly below the plane of the axes 43 and 44. The reason for this vertical displacement is discussed in detail below. It should be understood that such vertical displacement prevents the slide 47 from operating exactly 180 out of phase with the forming slide 17, but the phase relationship is close enough to provide sufficient dynamic balancing to permit high-speed machine operation.

The mass of the slide 47 and its stroke is selected so that the acceleration forces produced thereby are approximately equal to one half the acceleration forces produced by the forming slide 17. Similarly, the mass of the reciprocating mass 48 and its stroke determined by the eccentricity of the eccentric portion 56 is selected so that its acceleration forces are equal to about one half of the acceleration forces of the forming slide 17. Also the lateral displacement of the slide 47 from the central axis 44 is selected to be substantially equal to the lateral displacement of the line of action 53 from the central axis 44 so that the effective moment arms of the accelerating forces are balanced. With such an arrangement the thread rolling slide 47 and the reciprocating mass 48 provide substantially complete dynamic balancing of the forming slide 17 and the machine frame is not required to absorb any substantial force due to the reciprocating movement of the elements.

Dynamic balance of the rotating eccentric masses is also provided. The eccentric 56 which drives the reciprocating mass 48 is located on the opposite side of the crank shaft 11 from the main eccentric 46 and, therefore, provides part of the dynamic balance of the rotating eccentric mass 46. Similarly the eccentric drive 59 for the slide 47 is located on the opposite side of the crank shaft 11 from the main eccentric or crank section 46 so it cooperates with the eccentric drive 56 to provide substantially complete rotary dynamic balance of the main eccentric 46. Here again the fact that the eccentrics 56 and 59 are located substantially equidistant and from opposite side of the eccentric 46 minimizes force moments or couples in the machine.

The ily wheel 12 is provided with an eccentric rotary mass 62 which is adjacent to, but substantially 180 out of phase With, the eccentric 63 which drives the pitman 33. The size of the mass 62 and its effective eccentricity is selected so that it provides dynamic balancing for the mass of the eccentric 63 and in addition provides dynamic balancing for the adjacent portion of the pitman 33 which moves with substantially circular or rotary motion around the axis 43. Therefore, the mass 62 provides substantially complete dynamic balancing of the eccentric 63 and the adjacent portion of the pitman 33. It is again recognized that perfect dynamic balancing is not achieved, but the dynamic balancing that is provided is sufficiently complete to permit high-speed operation of the machine without destructive vibration.

In a machine incorporating this invention the eccen trically rotating masses are substantially balanced with respect to the axis of rotation 43 of the crank shaft 11 and 4are substantially symmetrical in lateral directions with respect to the central line of motion 44 of the machine. Similarly the reciprocating masses are in substantially complete dynamic balance since they are substantially 180 out of phase and are substantially symmetrical in a .lateral direction with respect to the line of action 44. Therefore, the machine provides sufficient dynamic balancing to prevent the destructive vibration from being induced in the machine as a result of acceleration forces applied to the crank shaft. The machine frame is sufciently massive to permit it to safely absorb any nonbalanced forces but is much less massive than would be required if substantially complete balancing were not provided.

The line of action 51 of the thread rolling slide is preferably located slightly below 4the central axis 44 of the machine so that the pitman 58 extends slightly in a downward direction toward the threader slide 47 when rearward acceleration of the thread rolling slide 47 is initiated. It is at this point in the cycle that the blank is rst fed in between the stationary thread rolling die and the reciprocating thread rolling die carried by the thread rolling slide 11. Since a certain a-mount of clearance is normally desirable in planar bearings of the type used to guide the thread rolling die, it is desirable to arrange the mechanism so that the thread rolling slide is loaded toward the lower bearing by its drive to insure that the clearance is always between the upper thread rolling slide bearing and the thread rolling slide at the moment the blank enters the dies. This insures that the exact proper position is maintained between the dies even if a substantial amount of clearance is provided in the slide bearings. Once the blank is started between the dies it tends to maintain the proper alignment between the dies so proper operation is maintained even if the pitman transmits an upward directed force during the latter portion of the rolling cycle.

Although a preferred embodiment of this invention is illustrated, it is to be understood that various modifications and rearrangements may be resorted to without departing from the scope of the invention disclosed.

I claim:

1. A forging machine adapted to form threaded articles comprising a frame, a die breast on said frame, a power-driven article forming slide reciprocable in said frame along a line of motion toward and away from said breast, said article forming slide and breast being adapted to carry cooperating tools and dies operable to form articles, a threader on said frame adapted to form threads on articles formed by said article forming slide, said threader including a stationary threader die support on said frame and a movable threader die support slide reciprocable on said frame along a line of motion substantially parallel to the line of motion of said forming slide, and drive means connecting both of said slides for driving said slides in timed relationship so that said slides each reciprocate through a cycle in the same period of time and accelerate and decelerate in opposite directions substantially simultaneously whereby each slide provides dynamic balancing of at least a portion of the acceleration forces of the other slide.

2. A forging machine as set forth in claim 1 wherein said drive means includes a crank shaft rotatable about an axis perpendicular to said line of motion of said forming slide, said crank shaft providing a crank portion associated with each slide, and a pitman connecting each slide and its associated crank portion, said crank portions being located substantially on opposite sides of said axis.

3. A forging machine as set forth in claim 2 wherein opposed bearings are provided ou said frame to guide said threader slide for reciprocating movement along its line of motion and such line of motion of said threader slide extends to one side of said axis, said pitman associated with said threader slide operating to urge said threader slide in a direction toward one of its bearings as said threader slide commences to move in a direction away from said axis.

4. A forging machine as set forth in claim 1 wherein said threader slide is positioned on one side of said forming slide, a reciprocating mass is mounted on said frame on the opposite side of said forming slide for movement along a line of motion substantially parallel to the line of motion of said forming slide, and said drive means is connected to drive said reciprocating mass through a cycle in which said reciprocating mass accelerates and decelerates in substantially the same direction substantially simultaneously with said threader slide, said threader slide cooperating with said reciprocating mass to provide substantially dynamic balancing of the acceleration forces of said forming slide.

5. A forging machine as set forth in claim 4 wherein said drive means includes a crank shaft rotatable about an axis substantially perpendicular to said line of motion of said forming slide, said crank shaft providing a crank portion associated with each slide and said reciprocating mass, and a pitman connecting each slide and said reciprocating mass to its associated crank portion, said crank portions associated with said threader slide and reciprocating mass being located on the side of said axis substantially opposite the crank portion associated with said forming slide.

6. A forging machine as set forth in claim 5 wherein said reciprocating mass is pivotally supported on said frame for reciprocating motion, the line of motion of said reciprocating mass being arcuate and substantially parallel to the line of motion of said slides.

7. A forging machine as set forth in claim 4 wherein said machine includes power driven accessories, said crank shaft providing an accessory drive including a crank portion and an associated pitrnan connected to drive at least some of said accessories in timed relationship to the movement of said slides, said crank shaft Ibeing provided with eccentric means to balance said accessory drive.

8. A forging machine as set forth in claim 7 wherein said crank shaft is supported on said frame by bearings spaced axially along said axis on opposite sides of said forming slides and said crankshaft is provided with eccentric masses arranged to provide substantially complete dynamic balancing of the rotating masses.

9. A forging machine adapted to form threaded articles comprising a frame, a die breast on said frame, a rotatable crank shaft, a forming slide reciprocable in said frame along a line of motion toward and away from said die breast, a pitman connected between said crank shaft and forming slide operable to reciprocate said forming slide in response to rotation of said crank shaft, a reciprocating mass on said frame on each side of Said forming slide, means connecting said crank shaft and each reciprocating mass operable to drive said reciprocating masses in timed relationship with said forming slide so that each reciprocating mass accelerates and decelerates in a direction pposite the acceleration and deceleration of said forming slide, said reciprocating masses cooperating to provide substantial dynamic balancing of the acceleration forces of said forming slide, one of said reciprocating masses being the threader slide of a roll threading mechanism.

10. A forging machine as set forth in claim 9 wherein said reciprocating masses are sized and spaced from said line of motion of said forming slide so that the force couples applied to said crank shaft by said reciprocating masses are substantially balanced with respect to said line of motion.

11. A forging machine as set forth in claim 10 wherein said crank shaft is formed so that the acceleration forces p of rotating eccentric masses are substantially dynamically balanced with respect to the axis of rotation of said crank shaft.

12. A forging machine as set forth in claim 11 wherein said crank shaft is formed so that the acceleration forces of the rotating eccentric masses are substantially dynamically balanced with respect to said line of motion of said forming slide.

References Cited UNITED STATES PATENTS 2,020,658 11/1935 Frost 10-12 2,141,951 12/1938 Criley 10-15 2,767,601 10/1956 Reed 72-445 2,857,157 10/1958 Bonquet 10-15 2,970,327 2/1961 Friedman l0-l5 3,116,499 1/1964 Friedman 10-11 3,222,913 12/1965 Leopold 72-429 3,229,496 1/1966 Foster et al. 72-429 3,496,581 2/1970 Haines 10-11 CHARLES W. LANHAM, Primary Examiner E. M. COMBS, Assistant Examiner

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