US3482429A - Hydraulic press - Google Patents

Description

D. L. LOMBARD HYDRAULIC PRESS Dec. 9, 1969 2 Sheets-Sheet 1 Filed March 27, 1968 l/V VE/V TOR. DAN/EL L. LOMBARD A I far/16y:

D. L. LOMBARD HYDRAULIC PRESS Dec. 9, 1969 2 Sheets-Sheet 2 Filed March 27, 1968 HVVE/V TOR. DAN/EL L. LOMBARD Afforneys United States Patent 3,482,429 HYDRAULIC PRESS Daniel L. Lombard, Youngstown, Ohio, assignor to Lombard Corporation, Youngstown, Ohio, a corporation of Ohio Filed Mar. 27, 1968, Ser. No. 716,540 Int. Cl. B2lj 9/18 US. Cl. 72450 2 Claims ABSTRACT OF THE DISCLOSURE This patent discloses making a high-capacity hydraulic press, especially one in which enormous tonnage may be concentrated on a small bed area and one in which a great eccentric load may be well accommodated, while maintaining the overall size of the machine within satisfactory limits, by using first and second pluralities of hydraulic cylinders, set on opposite sides of a working area containing top and bottom platens, each of the cylinders having an assoicated lever arm connected in force-multiplying arrangement With a crosshead with which the top platen is associated. In a preferred embodiments, the cylinders and the lever arms are set in a staggered relationship to save space.

CROSS-REFERENCES TO RELATED APPLICATIONS This application is related in subject matter to my copending application Ser. No. 667,760, filed Sept. 14, 1967.

BACKGROUND OF THE INVENTION Field of the invention The present invention relates to forging, extrusion or compaction of material, including metals, and in particular to a power-operated press of the fluid-operated or other type.

Description of the prior art Metal-forming presses of various kinds are known, among which are included ones relying upon hydraulic force to urge together a pair of platens encompassing the work, alone or with dies to operate upon it. As work comes to be done upon larger pieces and/ or metals of greater strength, the total force required to be exerted by the press rises, and there is a corresponding increase in the size and Weight of both the hydraulic cylinders used to exert the force and the frame or other means used to support the hydraulic cylinders in such manner that their force may be effectively applied to the work.

In recent years, with the development of exceedingly powerful jet engines, there has been a corresponding increase in the size of aircraft designed and built to be powered by such engines. Relatively little has been done, however, to increase the size of the forging presses used to shape, for example, fuselage or wing portions in such aircraft. The 50,000-ton-capacity presses now available are thus limited in the area of aircraft skin and strength members that they can efiectively shape in one push, yet their construction is already so massive and their cost is so expensive that without an improvement of some sort it is virtually inconceivable that larger presses can be economically produced and used.

3,482,429 Patented Dec. 9, 1969 Distinct advantages attend the use of a press of more enormous capacity, for example, 200,000 tons. A greater area with higher unit pressures is shaped in one push. These greater unit pressures and capacities enable larger pieces to be forged to dimensions more nearly those of the finished piece, so that considerably less machining is required to reach the final contour. The savings in manufacturing time that results from use of a press of ultrahigh capacity in the building of, for example, a fleet of 300 large jetliners (which may be of the kind that earn millions of dollars a year for the airlines operating them) have been apparent to those skilled in the art, but how to make a press substantially larger than any hitherto built without incurring costs correspondingly astronomical and encountering problems difficult or impossible to solve has not been obvious to skilled designers of presses. In particular, it has not been apparent to those skilled in the art how the above-indicated results could be obtained without using hydraulic equipment of unproven design and/or using unrealistic unit pressures.

It has been seriously proposed, for example, to build, at a cost of tens of millions of dollars, a direct-push hy draulic forging press of 200,000-ton capacity, using a cylinder with a 16-foot diameter bore and walls several feet thick with multiple-wall construction or new construction or new construction of unproven design and containing a gigantic frame ten stories high.

Although it is with reference to the construction of presses of ultrahigh capacity that the instant invention is most clearly novel and patentable, certain of the advantages of the invention attend the construction of presses of more modest size, such as ones of about 8000-ton capacities, so that the invention in its broadest aspects is not limited to presses of ultrahigh capacity. Among the advantages so retained in somewhat smaller presses are savings in weight per ton of capacity, ability to deal with eccentric loading, and for convenient providing of the concentration of the force of the press upon a relatively small bed area.

It is also known, for example, from my copending application Ser. No. 667,760, filed Sept. 14, 1967, to make a hydraulically operated press in which force is provided to a pair of platens by means of a plurality of hydraulic cylinders, each which operates an associated lever arm, with means being provided in the vicinity of the portions of the lever arm in contact with the platen and the pistons of the hydraulic cylinders, to insure that despite the arcuate movement of the lever arms in those vicinities during the operation of the press, the platen and the piston-rod ends move rectilinearly. In that application, however, it is not taught how a press of such design may be further improved in its capacity per ton of machine, ability to delivered high unit pressures to a work located in the concentrated area, and ability to withstand the effects of eccentric loading.

ISUMMARY OF THE INVENTION In accordance with this invention, the above-indicated problems are overcome by providing a press having, on opposite sides of the work area containing the upper and lower platens, first and second pluralities of hydraulic cylinders or the like, the cylinders preferably being ar ranged in staggered relationship and each cylinder having an associated lever arm arranged in force-multiplying relationship with one side, or the other, the movable crosshead containing a movable one of the two platens of the machine.

BRIEF DESCRIPTION OF THE DRAWINGS A complete understanding of the invention may be had from the foregoing and follow description thereof, taken together with the accompanying drawings, in which:

FIGURE 1 is a schematic elevation view of one embodiment of apparatus in accordance with the present invention;

FIG. 2 is a plan view, also schematic, of apparatus of the embodiment of the invention in accordance with FIG. 1;

FIG. 3 is an elevation view of the second embodiment of the invention; and

FIG. 4 is a plan view of the embodiment of the invention in accordance with FIG. 3, certain parts being omitted for the sake of clarity.

DESCRIPTION OF THE PREFERRED I EMBODIMENTS Referring to FIG. 1, there is shown schematically a press 2 comprising a main frame 4 having supports 6 and 8 for fulcrum pins 10 and 12, a crosshead member 14, upper and lower platens 16 and 18, respectively, a first plurality of cylinders 20, a second plurality of cylinders 22, a first plurality of lever arms 24, and a second plurality of lever arms 26. To insure that the cylinders 20 act together, there is provided a common plate or crosshead 27 upon which they all bear, and atop the crosshead 27, there are provided a plurality of box-like structures 29', each associated with an individual one of the lever arms 24 and serving to cause the lever arm to swing arcuately above its pivot 12, despite vertical rectilinear movement of the crosshead 27; this may be accomplished conveniently in various ways known to those skilled in the art, one of which is shown and described in my copending application Ser. No. 667,760, filed Sept. 14, 1967 with reference to FIGS. 10to13, inclusive, of that application. Similarly, a crosshead 31 and structures 33 are provided in association with the cylinders 22 and lever arms 26. Completing the apparatus of the embodiment shown in FIGS. 1 and 2 are pin members 28 and 30, which join the ends 32, 34 of the lever arms 24, 26, to the arms 36, 38 of the crosshead member 14, and wedge- like members 40, 42, which may be used to adjust the location of the top platen 16. As can best be seen in FIG. 1, when the cylinders 20 and 22 are activated, the lever arms 24, 26 are moved from the position shown in solid lines to the position shown in dash-dot lines, causing the pins 28, to be moved downward, with corresponding downward movement of the crosshead member 14 and top platen 16, so as to compress the work W between the platens 16, 18.

Referring now to FIG. 3, there is shown a second embodiment of the invention, comprising a base frame member 50. Associated therewith are a bottom platen 52 attached to an upstanding central portion 54 of the base frame member 50, and first and second pluralities of cylinders 56 and 58 arranged on opposite sides of the portions 54 of the base frame member 50. Crossheads 60 and 62 (not shown in FIG. 4, to promote the clarity of the showing) are associated with the cylinders 56 and 58, respectively, and these have mounted on them structures 63 and 65 (similar to the structures 29 and 33) that bear upon lever arms 64 and 66, which, as can be seen from FIG. 4, are, like the cylinders 56, 58, set in staggered relationship. The lever arms 64 engage, at one end, the structures 63 and, intermediate thereof, one or a plurality of pins 68. At the ends of the lever arms 64 remote from the ends engaging the structures 63, one or more other pins 80 connect the lever arms 64 to the arms 82 of a crosshead member 74, generally U-shaped, a top platen 76 being secured thereto by suitable means, as shown. Similarly, the lever arms 66 bear at one end against the structures 65 and, intermediate thereof, against one or a plurality of suitable fulcrum pins 78, with there being located at the ends of the lever arms 66 remote from the ends engaging the structures 65 one or more suitable other pins 70, by means of which the arms 66 are joined to the other arm 72 of the crosshead member 74.

In operation, the cylinders 56, 58 extend from the position shown in dash-dot lines to the position shown in solid lines to bring the lever arms 64, 66 to the position shown in solid lines, thereby lowering the top platen 76 toward the bottom platen 52, so as to compress work W located therebetween. Because of the staggered relationship of the cylinders 56, 58 and their associated lever arms 64, 66, a compact structure is obtained, and with the force being applied from opposite sides upon a generally U- shaped crosshead member by means of force-multiplying levers, there is obtained not only a great concentration of force but also, as a result of the design of the machine, a remarkable ability to resist the effects of eccentric loadmg.

It is desirable, of course, to arrange to have the crosshead member 14 or 74 move in a straight line, directly up or down, and suitable guides (not shown) are provided for that purpose. Inasmuch as the portions of the lever arms in contact therewith are moving arcuately, it is necessary to provide connections betweeen the crosshead member 14 or 74 and the lever arms in order that the pins may move laterally during a work stroke, it being convenient to provide slots for this purpose, as shown in FIGS. 1 and 3. Rather than having a pin 28, 30, 70 or 80 rest directly within a slot and make line contact with the interior surface thereof, it is to be understood that in each case the pin rests in area contact against a shoe that is arranged for sliding contact with the associated lever arm or crosshead member.

Similarly, it is most advantageous to have the power cylinders fixedly located, with their piston rods and/or rams traveling rectilinearly, yet the portions of the lever arms with which such rods or rams come into contact are moving arcuately. This may be compensated for conviently by the use of apparatus disclosed in my copending application Ser. No. 667,760, filed Sept. 14, 1967, especially FIGS. 10-13 thereof, which figures and description are hereby incorporated by reference with the same full force and effect as if set forth fully herein.

While I have shown and described herein certain embodiments of my invention, I intend to cover as well any change or modification therein which may be made without departing from its spirit and scope.

I claim as my invention:

1. A press comprising, in combination,

work-compressing means comprising a pair of platens extending horizontally,

a crosshead member associated with one of said platens and mounted for vertical rectilinear movement, said crosshead member having two arms,

a first set of lever arm means, each of said means comprising an arm member, a fulcrum, an operative connection to a first one of said arms of said crosshead rnember, and a force-receiving portion, with the locations of said fulcrum, operative connection, and force-receiving portion being such that forces applied to said force-receiving portion are transmitted in multiplied form to said operative connection, said means being on a first side of said work-compressing means,

a first set of hydraulic-cylinder means of said first set of work-compressing means, said hydraulic-cylinder means having rods to transmit forces to said forcereceiving portions of said argm members of said first set of lever arm means,

a second set of lever arm means, each of said means 3. 9 GQDQP 'SiHg an arm member, a fulcrum, an opera- 5 6 tive connection to a second one of said arms of said of hydraulic-cylinder means are arranged in staggered, crosshead member, and a force-receiving portion, interleaved relationship to said second set of lever arm with the locations of said fulcrum, operative conmeans and said second set of hydraulic-cylinder means. nection and force-receiving portion being such that forces applied to said force-receiving portion are References Cited transmitted in multiplied form to said operative con- 5 UNITED STATES PATENTS nection, said means being on a second and opposite side of said work-compressing means, and $235 a second set of hydraulic-cylinder means on said second set of said work-compressing means, said hydraulie- 10 CHARLES W LANHAM Primary Examiner cylinder means having rods to transmit forces to sand force-receiving portions of said arm members of said CROSBY, Assistant Examiner second set of lever arm means. 2. A press as defined in claim 1, further characterized in that said first set of lever arm means and said first set 15 72452, 453; 100-271

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