US3103136A

US3103136A - High energy impact machine

Info

Publication number: US3103136A
Application number: US72017A
Authority: US
Inventors: Leo C Bollar
Original assignee: Warner and Swasey Co
Current assignee: Warner and Swasey Co
Priority date: 1960-11-28
Filing date: 1960-11-28
Publication date: 1963-09-10
Anticipated expiration: 1980-09-10

Description

Sept, 10, 1963 1.. c. BOLLAR 3,103,136

HIGH ENERGY IMPACT MACHINE Filed Nov. 28, 1960 2 Sheets-Sheet 1 Q 89 V v 7 "1;. 84 INVENTOR.

q LEO C.BC LLDF2 78/- 69 26 W ATTORN EYS p 1963 L. c. BOLLAR 3,103,136

HIGH ENERGY IMPACT MACHINE Filed Nov. 28, 1960 2 Sheets-$heet 2 INVENTOR. '78

LEO C. BOLLQ/Q WQM ATTORNEYS of the ram.

United States Patent 3,103,136 HIGH ENERGY IMPACT MACHINE Leo C. Bollar, Pomona, Calif assignor, by mesne assignments, to The Warner & Swasey Company, Cleveland, Ohio, a corporation of Ohio Filed Nov. 28, 1960, Ser. No. 72,017 2% Claims. (Cl. 78-42) axial movements of the cylinder and ram move one of i the platens toward and away from the other platen.

The invention is primarily concerned with the control of high pressure gas delivery to the ram for displacement of the latter to bring the platens relatively together at high velocity and with delivery of great impact forces to the dies and their contents. As :a further example of this general type of high energy impact mechanism, reference may be had to my co-pending application, Serial No. 64,759, filed October 25, 1960, on Impact Machine. Structurally, the invention contemplates in its preferred embodiments, a ram reciproca'ble within the cylinder and having a free end subject to sudden exposure to high gas pressure communicated to the cylinder to eifect high velocity displacement of the ram in its working stroke. In certain of its major aspects, the invention is directed to novelmeans for sealing oil the ram from such exposure in its starting position, and lior releasing the seal to permit communication of the actuating gas pressure to the ram. Although not to be construed as limited thereto in its broader aspects, the invention will be described in reference to a structural arrangement according to which the ram is receivable within an opening contained in a wall dividing the cylinder into a high pressure chamber from which the actuating gas pressure is derived, and a displacement chamber within which the ram travels in its working stroke.

The invention contemplates what is believed to be a new concept of ram sealing means in machines as characterized in the foregoing, where the sealing means performs the dual functions of effecting a seal between the high pressure chamber and 'a transverse area of the rain, and of being releasable or controllably allowed to permit leakage of the high pressure gas, to initiate advancement In the accomplishment of this objective I place within a ram-receiving opening between the pressure source and displacement chamber, a radially constrictable or expansible seal means which in constricted condition acts as a seal, and when expanded allows gas flow or leakage to the effective pressure area of the ram. Preferably I employ a seal of this character which is controllable as to its constricted or expanded condition by fluid pressure applied independently of the ram-actuating gas pressure. Thus, maintenance of the ram against displacement, and initiating of such displacement, are simply controllable in terms of fluid pressure communicated to the seal. As will appear, in addition to serving these functions, the seal means presents the additional advantage of not being dependent for its scaling function upon precise positioning of the ram, but instead,of having the capacity to assure a gas-tight seal with the ram variably (axially) positioned within the seal.

Preferably the ram is designed to include a piston section spaced from its free end and workable within the displacement chamber. When the ram is so constructed, the seal means is adapted to communicate pressure to 2 both end and piston areas of the ram. For this purpose I may provide within the ram-receiving opening, a pair of seal rings spaced apart to permit delivery of the high pressure gas between the rings. In constricted condition the latter seal oil gas flow respectively to the ram end and piston areas, and when expanded, the rings allow gas leakage to those areas to initiate the ram stroke.

The invention has various additionalfeatures, objects and details, including improvements in the later described cushioning interconnection between the cylinder assembly and its platen, all of which will be understood more fully from the following detailed description of the accompanying drawings in which:

FIG. 1 is a View showing the machine in vertical section with the ram positioned at the top of its stroke;

FIG. 2 is a similar view showing the ram advanced substantially to impacting position;

FIG. 3 is a reduced scale cross-section on line 3-3 of FIG. 2;

FIG. 4 is an enlarged fragmentary cross-section showing one of the seal rings; and 3 FIG. 5 is a further enlarged fragmentary cross-section illustrating both seal-rings and constricting fluid pressure communications thereto.

Referring first to FIGS. 1 and 2, the machine may be characterized as comprising ram and cylinder assemblies indicated at 10 and 11 and connected respectively to

platens

12 and 13 so that relative axial moyemen-ts of the ram and cylinder assemblies from the FIG. 1 position to the FIG. 2 position, bring the platens relatively together at high velocity. The platens may be adapted to carry any suitablework forming means such as metal forging or extrusion dies, of which the forging dies 14 and 15 are illustrative. As will later appear, the cylinder assembly 11 is connected to platen 13 preferably by means 16 functioning not only as interconnections causing the cylinder assembly and platen totravel together, but also to cushion the high energy die or work metal impact.

The cylinder assembly 11 is shown to comprise a cylinder 17 having a bottom closure 18 and a flanged head 19 connected by tie bolts 20 to a base plate 21. The cylinder is divided into an upper high pressure gas chamber 22 and a lower displacement chamber 23 by a fixed Wall assembly including an annular ring 24, a concentric tubularjsection '25 seated therein, a top flanged head or closure 26, and tie bolts 27 connecting the head with ring as and clamping the tubular section 25 therebe-tween. Section 25 contains circularly spaced ports 28 for the passage of gas from charnber 22 to the working areas of the ram 10, all as will later appear. The rain shown to have a free end portion 29 receivable within a cylindrical opening 30 defined by the smoothly continuous opening 31 in ring 24 and the bore of the tubular section 25. The ram also has a piston 32 reciprocably engaged with the wall of the cylinder 17 in the displacement chamber 23. The lower portion of the ram extends slidably'through opening 33 in the cylinder closure 18 and is terminally connected, as by threaded reception at 34, with the platen 112.

Referring particularly to FIGS. 4 and 5, tube 25 contains below ports 28 an internal annular recess 35 and has above the ports a counterbore 36 forming with the head 26 an annular recess 37. Each recess contains an annular seal ring 38 which is elastically resilient and capable of constriction by externally applied fluid pressure into fluid-tight sealing engagement with the surface of the ram 29 and the top and bottom recess-defining surfaces. The rings 38 may be made of suitable self-restoring organic plastic material, sufficiently tough to resist prolonged wear, and of which Teflon is illustrative. As illustrated, each seal ring is roughly diamond-shaped, with the seal ring recesses.

flattened top and

bottom faces

38a and 38b bearing against the annular top and bottom surfaces of the ringcontaining recess, and flattened inner and outer surfaces 380 and 38d, the latter being engageable with the cylindrical ram surface. The seal rings are adapted to be I circularly constricted by fluid pressure, such as high pres- ,sure oil, suitably delivered to recesses and 37 at the outsides of the rings, as by way of passage 40 and conduit 41 having

branches

42 and 43 leading respectively to The ram surface contains an annular recess 44 which in the up position of the ram shown in FIG. 1 bridges the ports 28 and terminates closely approximate the bottom of recess 37 and the top of recess 35 so as to be capable of passing high pressure gas from ports 28 through leakage clearance through the upper ring 38 and the ram surface 29a to space 45 above the end face 46 of the ram. The recess 44 also is adapted to pass the high pressure gas from ports 28 for leakage past the lower seal ring 38 and the ram surface 29b through clearances at 47 and '48 into the displacement chamber 23 so that the leakage pressure is communicated to the piston surface 49. The latter is shown to be flared downwardly and outwardly in correspondence with the angularity of the under surface 50 of ring 24, the two surfaces being interengaged, or close to interengagement in the FIG. 1 up position of the ram. 7

The ram and cylinder assemblies 10 and 11 are returnable from their FIG. 2 positions to the starting positions of FIG. 1 by eitherof two methods. In the one instance, gas may be introduced through line 52 past two-way valve 53 into chamber 23 at pressure sufficiently high to overcome the total pressure acting against the ram surfaces .46 and 49, and thus return the parts to the FIG. 1 position, following which the pressure in chamber 23 may be released through line 54 in advance of the ram down stroke. Alternatively, the ram may be elevated from its FIG. 2 position by high pressure fluid, such as an oil,

introduced-through line 55 and passage 56 beneath a piston 57 engageable upwardly against the ram and capable of elevating thelatter to starting position, following which the pressurized fluid is released from the chamber.

Through the interconnections at 16, the cylinder base 21 is associated with the platen 13 in a manner permitting simultaneous upward displacement of the platen and cylinder assembly, and further travel of that assembly beyond the point of die impact. Each of the interconnections 16 comprises a tube 60 slidable through opening 61 in the platen 12, the upper extent of each tube being threaded I through the cylinder base 21 and held in variably adjustable position relative thereto, by nut 62. The tube has a der contained, as illustrated, within the platen assembly. High pressure gas derived from a suitable source such as accummulator 71 is delivered through line 72 to chamber 22, and through line 73 into space 74 within each tube 60, fronrwhich the gas flows through orifice 75 into chamber 76 and is communicated through passage 77 into chamber 78 below a floating piston 79 and fixed centrally apertured insert 301- High pressure oil is introduced through line 64 into chamber 81 to controllably vary the vertical positioning of tube 60 and piston 66 within the cylinder 70, thereby controllably varying the gas volume at 76 above the piston and the cushioning eflect of the gas confined therein at the point of die or work rmetal impact. The tendency for downward movement of the tube 60 and piston 66 within cylinder 70 is cushioned by displacement of oil from chamber 81 throughopening 82, acting to displace piston 79 downwardly with resulting compression of gas in chamber 78.

Suitable provision may be made for ejecting the forged Q object (not shown) from die 15, automatically in response to return travel of the platen from the FIG. 2 to the FIG. 1 positions. As illustrative of such means the platen 13 may contain a cylinder 83 slidably contained within the platen bore 84, the bottom of the cylinder containing a plug 85 having a passage 86 through which pressurized gas is supplied to the cylinder. The latter is secured at 87 to a base plate 88, which in turn may be attached stationarily to a floor, not shown. Cylinder83 contains a fixed head 89, the rod 90 of which extends upwardly into the platen bore 91. The rod 90 carries a seal ring 92 and contains a passage 93 through which the gas pressure within the cylinder is communicated about the rod below the seal 92 and to space 94 above the head, such communication occurring even though the rod may. have but slight clearance within bore 91 below the seal. The die 15 is shown to contain an ejector having a head 95 receivable downwardly within the recess 96, and a pin 97 extending down through the die .into bore 91.

in considering the operation of the machine, accumulator 71 and the communicating

chambers

22, 76 and 78, are charged with high pressure gas, typically upward of 2000 psi. and at the cycle start, the parts are positioned as in FIG. 1. Here by the introduction of high pressure fluid through

passages

42 and 43 through the outsides of the seal rings 38, the latter are deformed to the extent of expanding axially into fluid sealing engagement with the top and bottom surfaces of their respective recesses, and of constructing into fluid-tight sealing engagement with the

ram surfaces

29a and 29b. Gas pressure precharged through line 52 into chamber 23 maintains the ram in its elevated position and need only be suflicient for that purpose. In order to initiate the ram downstroke, the fluid pressure is released from outside of the seal rings, allowing them to expand by reason of their elastic tendency toward restoration, allowing high pressure gas leakage from the ram recess 44 past the upper seal ring 38 to the end surface 46 of the ram and downwardly past the lower seal ringthrough the clearances at 47 and 48 against the top surface 49 of the ram piston. The resulting pressure communication displaces the ram downwardly out of the seals, and releases the ram with a suddenness compatible with the total objective of projecting the ram on its working stroke at extremely high velocity. The precharged pressure in chamber 23 may be released at the initiation of the ram down stroke.

Release of the ram assembly as described, results in upward displacement of the cylinder assembly and tubes 60 with consequent compression of the gas in chambers '76. The effect is to elevate the paten 13 to the point of die impact, following 'which the impact is cushioned by over-travel of the tube 60 and further compression of gas in chambers 76. The resulting compression tends to produce oscillation of the platen 13 downwardly, which is cushioned by displacement of pistons 79 (by reason of the downward oil displacement through openings 83), and compression of the gas in chamber 78, the total effect being to produce a rapid dampening-out of the oscillations.

Following the Working stroke, the ram assembly may be restored from its FIG. 2 position, either by pressurized gas introduced through line 52, or by the action of piston 57, as previously described. Gas may be displaced from above ports 28 and the top of the rain as it approaches its uppermost position, through a suitable vent such as line L containing valve V. As the platens 1-2 and 13 move relatively toward restoration, rod 92 engages the ejector rod 97, elevating the head 95 within the die cavity to displace the workpiece therefrom.

During restoration of the ram assembly to its upper or starting position, the seal rings 38 remain unpressurized, i.e. without introduction of pressure fluid through

lines

42 and 43, so that the rings have sufficient openness to receive the ram surfaces 29a and 2%. When the ram reaches its upper positions, the seal rings are then pressurized to so retain the ram preparatory to the next cycle start.

I claim:

1. A high energy impact machine comprising a pair of spaced platens, a cylinder connected to one of the platens and a ram contained in the cylinder and connected to the other platen so that opposite relative axial movements of the cylinder and ram move one of the platens toward and away from the other platen, the ram having a terminal portion receivable within a bore in the cylinder, a source for high pressure gas to be communicated to a transverse area of the ram for displacement of the ram from an initial position to bring the platens relatively together at high velocity, seal means positioned about the ram and interposed between the ram and Wall of said bore, said seal means being displaceable relative to the ram and bore wall and being operable in one condition to seal 01f said gas communication to the ram area and operable in another condition to permit such communication, and means for displacing said seal means from one to the other of said conditions independently of said high pressure gas and independently of ram movement.

2. A machine according to claim 1, in which said seal means is resilient and elastic and is self-restorable from displaced condition.

3. A machine according to claim 1, in which said seal means comprises a resiliently deformable ram engaging ring having essentially fiat opposed sides and ends intersected by angular corner surfaces.

4. A machine according to claim 1, including means forming an annular ram encircling recess containing said seal means and to which said fluid pressure is communicated.

5. A machine according to claim 1, in which said seal means includes a pair of said deformable seal rings surrounding and spaced axially of the ram.

6. A machine according to claim 1, in which said ram includes a piston section slidably engaging the cylinder wall and a terminal portion surrounded by said seal means.

7. A machine according to claim 1, in which said seal means surrounds and engages a cylindrical surface of the ram and is effective to seal about the ram in different axial positions of the ram within the seal.

8. A machine according to claim 1, including platen impact cushioning means in the connection between said one of the platens and the cylinder.

9. A high energy impact machine comprising a pair of spaced platens, a cylinder connected to one of the platens and a ram contained in the cylinder and connected to the other platen so that opposite relative axial movements of the cylinder and ram move one of the platens toward and away from the other platen, said cylinder containing pressure and displacement chambers separated by a wall containing an opening within which an end position of the ram is receivable in a starting position of the ram and out of which the ram is 'displaceable at the start of its power stroke, means for supplying high pressure gas to said chamber for communication to a transverse area of the ram to displace the ram in its power stroke and bring the platens relatively together at high velocity, seal means including a radially constrictable and expansible seal ring interposed between the ram and wall of said opening and operable in constricted condition to seal off said high pressure gas communication to the ram area and operable in expanded condition to allow said communication, and means for controllably constricting said ring.

10. A machine according to claim 9, in which said opening is in the form of a cylindrical bore within which said ring is eitective as a seal at different axial positions of the ram therein.

11. A machine according to claim 9, including means for communicating fluid pressure independently of said gas pressure to the seal ring to effect said constriction.

12. A machine according to claim 9, in which the expanded seal ring permits leakage of the gas to a free end of the ram.

13. A machine according to claim 12, in which said ram includes a piston section in said displacement chamber and engaging the wall of the cylinder, and said seal ring in expanded conditions permits high pressure gas leakage to said piston section.

14. A machine according to claim 9, in which said wall contains a closed end portion containing a cylindrical bore forming said opening, and the last mentioned gas pressure is communicated to a space between the end of the ram and the closed end of said wall.

15. A machine according to claim 14, in which said seal means includes a pair of seal rings spaced axially of the ram within said bore.

16. A machine according to claim 15, in which said high pressure is communicable to the end of the ram through an opening in said wall between the seal rings.

17. A machine according to claim 15, in which said seal rings are radially elastic and radially constrictable by fluid pressure from non-sealing relation to sealing engagement with the ram, and said constricting means includes means for communicating fluid pressure to the rings to so radially constrict them.

18. A machine according to claim 17 in which said seal rings in said non-sealing relation allow gas leakage from said high pressure chamber to the end face of said ram and into said displacement chamber, and in which the ram includes a piston within said displacement chamber and engaging the cylinder wall.

19. A machine according to claim 9, in which said ram has in said displacement chamber a piston seal ring engaging the cylinder wall, and comprising also an annular piston surrounding the ram and operable by fluid pressure to return the ram into said opening following the power stroke of the ram.

20. A machine according to claim 9, including platen impact cushioning means in the connection between said one of the platens and said cylinder.

References Cited in the file of this patent UNITED STATES PATENTS 1,893,187 Urbanek Jan. 3, 1933 2,384,163 Flowers Sept. 4, 1945 2,648,949 Taylor Aug. 18, 1953 2,960,067 Osborne Nov. 15, 1960

Claims

1. A HIGH ENERGY IMPACT MACHINE COMPRISING A PAIR OF SPACED PLATENS, A CYLINDER CONNECTED TO ONE OF THE PLATENS AND A RAM CONTAINED IN THE CYLINDER AND CONNECTED TO THE OTHER PLATEN SO THAT OPPOSITE RELATIVE AXIAL MOVEMENTS OF THE CYLINDER AND RAM MOVE ONE OF THE PLATENS TOWARD AND AWAY FROM THE OTHER PLATEN, THE RAM HAVING A TERMINAL PORTION RECEIVABLE WITHIN A BORE IN THE CYLINDER, A SOURCE FOR HIGH PRESSURE GAS TO BE COMMUNICATED TO A TRANSVERSE AREA OF THE RAM FOR DISPLACEMENT OF THE RAM FROM AN INITIAL POSITION TO BRING THE PLATENS RELATIVELY TOGETHER AT HIGH VELOCITY, SEAL MEANS POSITIONED ABOUT THE RAM AND INTERPOSED BETWEEN THE RAM AND WALL OF SAID BORE, SAID SEAL MEANS BEING DISPLACEABLE RELATIVE TO THE RAM AND BORE WALL AND BEING OPERABLE IN ONE CONDITION TO SEAL OFF SAID GAS COMMUNICATION TO THE RAM AREA AND OPERABLE IN ANOTHER CONDITION TO PERMIT SUCH COMMUNICATION, AND MEANS FOR DISPLACING SAID SEAL MEANS FROM ONE TO THE OTHER OF SAID CONDITIONS INDEPENDENTLY OF SAID HIGH PRESSURE GAS AND INDEPENDENTLY OF RAM MOVEMENT.