US2516170A - Hydraulic press intensifier attachment - Google Patents

Description

July 25, 1950 c. E. ADAMS 2,516,170

HYDRAULIC PRESS INTENSIFIER ATTACK-DENT Filed Feb. 24, 1947 -s Sheets-Sheet 1 I i INVENTOR. 27 BY CECIF E. ADAMS Fig, 1 MKMM July 25, 1950 c. E. ADAMS 2,515,170

HYDRAULIC PRESS m'rmusxmsn A'mcmmr Filed Feb. 24, 1947 5 Sheets-Sheet 2 INVENTOIL CECIL E. ADAMS Fig. [2 M F MCZMM,

y 1950 c. E. ADAMS mnmuuc mass INTENSIFIER ATTACHMENT 5 Sheets-Sheet 3 Filed Feb. 24. 1947 INVENTOR. CECIL E. ADAMS BY $401M 43mm FIG 5 y 25, 1950 c. E. ADAMS 2,516,170

. HYDRAULIC PRESS INTENSIFIER ATTACl-MENT Filed Feb. 24, 1947 5 Sheets-Sheet 4 INVENTOR CECIL E; ADAMS Fig; 4 MKW July 25, 1950 Q E. A AMS 2,51 ,110

Fig. 8

IN VEN TOR.

WKWM m CECIL E. ADAMS BY the operator.

Patented July 25, 1950 HYDRAULIC PRESS mmsn'm ATTACHMENT Cecil E. Adams,

Denison Columbus, Ohio, am to The Gala-bus,

Ohio, a corporation of Ohio Application February 2!, 10, Serlallio. 730,5

I 7 Claims.

This invention relates to hydraulic apparatus and is, in its more specific aspects, directed to hydraulic pressin mechanism. Still more specifically, the invention is directed to an attachment for presses by which the force exerted by the pressing ram may be intensified or multiplied.

One of the objects of this invention is to provide an attachment for a press which may be used with presses of low pressing force to perform pressing operations requiring high pressing forces.

Another object is to provide an attachment of the type mentioned in the preceding paragraph which will be operated entirely by hydraulic pressure.

A further object of the invention is to provide a hydraulic attachment for a press which will be operated entirely by the motion of the ram of the low capacity press to which it is applied to develop pressing forces of high tonnage.

A still further object of the invention is to provide mechanism for attachment to a press to be operated by the ram thereof, which mechanism includes a second ram and means for transmitting motion from the ram of the first press to the second ram to cause the same to move relatively rapidly until a certain resistance is encountered and then slowly and with increased force, the transition from low to high force taking place automatically and without attention or action by Another object is to provide a hydraulic mechanism for use with a hydraulically actuated ram for multiplying the force of the ram without changing or otherwise altering the hydraulic circuit containing the ram.

Another object is to provide a press attachment for intensifying the force applied to the press ram, the attachment having a fluid transmitter and translator, the former being operated by the pressing ram and the latter having a second ram, the attachment including mechanism for multiplying the efiectiveness of the transmitter.

A further object is to provide an attachment for a hydraulic press having a ram, the attachment also having a ram and a hydraulic motiontransmitting mechanism whereby movement of the ram of the press will cause similar movement of the ram of the attachment, the motion-transmitting mechanism having a transmitter and a translator with pistons of predetermined relative areas and means for changing the relation of the piston areas during a cycle of operation of the press and attachment.

Another object is to provide an attachment for a hydraulic press, the attachment having a ram disposed for sliding movement in a cylinder and a pump-like device having a piston movable in a cylinder, the piston being directly connected with theramofthepress,movementoftheramservingtoeausethepistontopumpiluidintothe cylinder of the attachment to cause movement of the ram thereof, the attachment having means responsive to fluid pressure generated by resistance to movement of the ram thereof to establish communication between opposite ends of the pump cylinder whereby the effective area of the pump piston will be reduced to the area of the pistonrod connecting the piston to the press ram. Through the reduction of the piston area in this manner a differential efiect will be produced which will multiply the force developed by the press ram in the ratio which the area of the pistonrodbearstotheareaoftheramofthe attachment.

Further objects and advantages of the present I invention will be apparent from the following description, reference being had to the accompanying drawings wherein a preferred form of embodiment of the invention is clearly shown.

In the drawings:

Fig. 1 is a diagrammatic view of a hydraulic system employed in a press and attachment formed in accordance with the present invention.

Fig. 2 is a side elevational view of a press and attachment embodying the present invention.

Fig. 3 is a detail vertical sectional view taken through one portion of the attachment, this portion constituting the transmitter of the motiontransmitting mechanism.

Fig. 4 is a detail verticalsectional view taken through another portion of the attachment, this portion including the translator of the motiontransmitting mechanism and apparatus operated thereby.

Fig. 5 is a detail longitudinal sectional view taken through an automatic valve forming a part of the attachment, on the plane indicated by the line V-V of Fig. 3.

Figs. 6 and I are detail vertical sectional views taken through the automatic valve shown in Fig. 5, the sections being taken on the planes indicated by the lines VI-VI and V1IVII, respectively, of Fig. 5.

Fig. 8 is a detail vertical sectional view taken through the valve on the plane indicated by the line VIIIVIII of Fig- 6.

Referring more particularly to the drawings, numeral 2| designates generally a press to which the attachment 2| may be applied. This attachment may be used with of varying charam, but; 101- of the power cylinder 23.

purposes or convenience. it

isillustratedasappliedtoahydraulicpressot" the type shown diagrammatically in my copending application Serial No. 869.657 flied May 14, 1946, now Patent No. 2,488,109. The press 23 is supported on a base 22 which may be suitably formed. The press includes airame 23 or generally c-shape having a" bolster section 2l column section 25 and a head section it, these sec-' tions being integrally iolned. The frame contains a reservoir 21, a motor-driven pump 23, and a power cylinder 29, the latter being located in the head section and having a ram 33 projecting downwardly therefrom through a packing gland 3| flxed to the under side oi! the head section 23.

I The ram 33 is provided with a rearwardly pro;-

jecting arm 32, the outer end of which surrounds a shipper rod 33 utilized to govern the operation of a control valve 34, this valve being shown diagrammatically in Fig. 1: Such valve may be of many diflerent types, the bne illustrated-coniorming to that disclosed in the above-mentioned copending application.

Valve 34 is disposed pump 23 and functions .to control the flow oi fluid from the pump through lines 35 and 36 extending to the upper and lower ends, respectively, As in the copending application the valve may be manually operated to effect the reciprocation of the piston 31 in the power cylinder. While the valve .3! has been shown and described in -detailin thecopending application mentioned, a brief descrip-' tion will be given here to facilitate an understanding of the press attachment forming the subject matter of this invention. Valve 34 includes a body 3| having a bore Ill formed therein together with a plurality oi: annular grooves spaced longitudinally of the bore 40, these grooves being designated by numerals to ll, inclusive. Groove 45 is connected by, a line 43 with the outletloi the pump 23 whilegrooves l3 and 46 are connected with lines '36 and 35', respectively, which lead to the lower and upper ends the power cylinder 23. Groove 41 is connected by line 50 with reservoir 21, this line serving as the exhaust passage from the valve to the reservoir. 4 To control the flow of fluid to and from the power cylinder, bore lll is provided with a spool 3| which is directly connected at its lower end to the shipper rod 33 so that movement may be transmitted from the latter to the former in the operation of the press. Spool ii is formed with an internal chamber 52 and a plurality of lateral ports 53 to 59, inclusive, certain ports registering with certain grooves in the body in various longitudinal positions of thespool- Chamber 52 is formed for the reception of a shuttle valve H which serves to connect various ports in the spool I. Shuttle valve 6] includes a pair of longitudinal=ly spaced lands 6! and 53 between which an annular groove 64 is formed, this groove providing a passage to connect certain lateral ports in the spool ii. The shuttle valve is also provided with a. central socket 65 to receive the lower end of a coil spring 66, the opposite end of which is disposed in a socket 61 formed in a cap 63 applied to the open upper end of the spool Spring It normally tends to. urge the shuttle-valve il downwardly to the lowermost position, illustrated in Fig. l, and when the shuttle valve occupies this position the groove 64 connects grooves 45 and 43 so that fluid from the pump 28 may then flow from line 43 to line 36 which leads to the lower end of the power cylinder T2 9. .when the shuttle in the outlet line of the arm 32 will engage a collar on shipper rod 33 and move the shipper rod. together with spool I i u'pwardly until ports ll are moved out or registration with groove 43. Fluid flow to the lower end of power cylinder II will then be discontinued and piston movement will stop.

Movement of the piston in the opposite direction or downwardly, is initiated by raising the shipper rod 33 and spool Ii until ports 53 register,

with groove 42. At this time fluid may flow from line 43 upwardly in a bore 33 to a chamber II which is connected by a passage II, with groove 42. Fluid. admitted to this groove will flow through ports 53 into the lower end of chamber 52 beneath shuttle valve it. This fluid under pressure will force the shuttle valve upwardly in opposition to spring 33 until the upper end thereof engages the bottom oi. the cap ii at which time groove 84 will establish communication between ports which are then in registration with groove 45, and ports l1 registering with groove 43.

Fluid from the pump 23 may then flow from line 08 through line 33 to the upper end jot power cylinder 29. The force of this fluid will move piston '31 downwardly forcing fluid from the lower end of the power cylinder through line 36 to groove 3 through ports ll into transverse ports ll-A formed in the shuttle valve I at the land 2. Some of this fluid, will flow downwardly through a reduced port I2 in the lower portion of the shuttle valve to the lower end of the chamber 52. This fluid will serve to maintain a pressure beneath the shuttle valve, which pressure will hold the shuttle valve in its elevated position in opposition to the force of the spring 65.

The balance of the fluid flowing into passages I i--A will escape through passage 13 and sockets i5 and 31 to bore" which leads from chamber 52 to groove 41, this. fluid then escaping through line 50 toreservoir 21.

While piston 31 is moving downwardly and fluid is being exhausted through line 36 and the path mentioned above, the shuttle valve will be held in an elevated position to continue to direct fluid flow from pump 23 to the upper end of the power cylinder. When this flow is initiated, some of the fluid supplied to groove 46 will flow through an angularpassage-li'to' a chamber 15 at the upper end of bore i3. This fluid may flow through ports ll iormed in a valve housing II and around a'needle valve- 33 adiustably positloned in thisj'houslng, to the space above a spring-elevated plungerfla Fluid applied to the upper end of this. plunger will force the same downwardly to discontinue the flow of fluid from line 48 to chamber 13 and the under side of the shuttle valve. 'Sincefhowevei; fluid being exhausted from the lower end of the power cylinder serves to-hold'theshuttle valve in its position, downward movement of piston 31 will not be interrupted.

When the piston reaches the lower limit of its travel in a downward direction. either through 5. lief valve 18 to bypass fluid from line 48 to reservoir 21, fluid flow from the lower end of power cylinder 29 will be interrupted and spring 85 may then move shuttle valve 8| to itslowermost position, fluid pressure beneath the shuttle valve being dissipated through passages 12 and 18. when the shuttle valve drops in this manner, fluid under pressure will be directed to the lower end of the power cylinder to cause the piston to move in an upward direction. If the needle valve 80 is properly adjusted, plunger 8I will be moved upwardly by its spring Iorcing'the fluid from the space above the plunger through the valve housing 18 and passage 15 to groove 48 from which it will flow to reservoir 21. When plunger 8I moves again introduced to groove 42 to actuate the shuttle in opposition to the spring 55 causing the piston 31 to resume movement in a downward direction The distance traveled in the reverse or upward direction by piston 31 will be determined by the setting of needle valve 88. The mechanism thus far described is identical with that set forth in the above-mentioned copending application, the operation thereof also being identical.

From the foregoing description it will be appareat that the ram 38 may be caused to reciprocate either throughout the full stroke by completely closing needle valve 88 or through shorter strokes the lengths of which are determined by the ad- ,i'ustment of the needle valve. As usual in hydraulic presses, the force exerted by the ram 80 will be determined by the area of piston 31 and the pressure on the fluid applied thereto. As pointed out in the objects, the attachment 2I has been provided to eifect a multiplication or intensification of the force exerted by the ram 88. To secure this effect, the transmitter 82 of a hydraulic motion-transmitting mechanism is applied to the bolster 24 of the press 28. This transmitter includes a casting 83 having a chamber 88 formed therein. This chamber receives a piston 85 having a piston rod 88 projecting from the upper end, this pistonrod is connected with the lower end of the ram 30 so that movement of the piston 31 in the power cylinder will be di rectly transmitted to the piston 85.

- Chamber 84 is connected by a passage 81 with the upper end of a chamber 88 formed in the .head 90 of the attachment frame 9I, the head 98 being supported by comer posts 92 extending upwardly from a bolster 93. This bolster is held in horizontal registration with the bolster 24 oi! the press frame by a stand 94 formed of tubingor other suitable material, leveling means 95 being provided to secure the proper position of the bolster. The bolsters 24 and 93 are connected by side plates 98 which are bolted or otherwise secured to the sides of the press frame and the attachment frame. When the piston 31 in the power cylinder 29 moves downwardly, similar mo- .tion will be transmitted to the piston 85. This motion of piston 85 will discharge fluid from cylinder 84 through line 81 into the upper end of chamber 88. The force of this fluid will cause ram 91, which is slidably positioned in chamber 88, to move downwardly and impart similar movement to platen 98 which is guided for sliding movement on the corner posts 92. Downward movement of the platen is resisted by coil springs 988 which surround rods IOI projecting upwardly irom the platen through openings in head 98,

91 and platen 98, springs I00 will be compressed so that when fluid pressure is relieved above the piston 91, the springs will return the piston 91 and the platen 98 to their elevated positions.

Casting 88 is provided with a horizontally extending bore I04 in which aported sleeve I8! is disposed, this sleeve having longitudinally spaced sets of ports I88 to I09, inclusive, and slidably receiving a spool III. This spool has a pair or annular grooves H2 and H8 formed therein for the purpose of connecting certain sets of ports in various positions 01' longitudinal movement of the spool. Normally, the spool is urged toward one end of the bore by a coil spring I I4 having one end disposed in a socket formed in the spool and the other end positioned in a socket formed in a cap II5 employed to close one end of bore I04. A second cap II6 closes the opposite end of the bore, these caps also serving to maintain the longitudinal position of the sleeve I05. The left end of the spool III, as viewed in Fig. 5, is also provided with a socket for the reception of a piston iI1, the spool having ports II8 formed therein to establish communication between groove I I3 and the socket at the inner end of the piston I I1. Ports I 89 in the sleeve I are in open communication with the lower end of chamber 84 through a passage I28 formed in the casting 88 while ports I08 are connected with the upper end of the chamber by a second passage IZI, also formed in casting 83. When the spool II I is normally positioned as shown in Fig. 5 communication between ports I88 and I89 is obstructed. Groove H2 in the piston, however, establishes communication between ports I81 and I88, at this time, the former ports being connected as shown in Fig. 1 by conduit I22 with reservoir 21.

It will thus be seen that, as piston 85 moves in a downward direction, fluid from reservoir 21 may flow through conduit I22, ports I01, groove 2,

8 ports I88, and passage I 2| to the upper end of chamber 84 to fill the portion of chamber 84 above the piston 85. If, in its downward movement, platen 98 engages an obstruction, fluid pressure in the upper end of chamber 88, in passage 81 and in the lower end of chamber 84 will increase. This pressure will be introduced through passage 828, ports I09 and H8 to the socket at the inner end of piston II 1. This fluid pressure will react to urge spool III toward the right end of bore I84 in opposition to the spring H4. 11 the pressure is sufflciently high, spool III will be moved until groove II3 establishes communication between ports I88 and I89 and interrupts communication between ports I01 and I88. When ports I88 and I89 are connected, communication will be established between the opposite ends of chamber 84 and fluid may then flow from the lower end of chamber 84 to thevupper end thereof above piston 85. It will be obvious that only the fluid displaced by the difierence in area between the piston and the piston rod 88 will flow to the upper end of the chamber 84, the remaining fluid displaced continuing to flow into the upper end of chamber 88. It will thus be seen that the efiective area of piston 85 will have been reduced to the area of the piston rod 88. The relation between piston 85 and ram 91 will therefore be changed causing the latter member to exert an increased force. The force exerted by ram 88 will thus be multiplied or intensified.

I 7 when ram 01 ceases to move. ram 30 will be and shuttle valve I will be shifted to the direction of ram ll. Piston I! will aisobereversedandcausedtomoveinan upward direction. As soon as pressure is relieved v in the connected ends of chambers 84 and .2, spring lilwillshiftspool illbaclrtotheposition shown in Fig. 5 in which position communication between the ends of chamber 24 is obstructed. At this time the upper end of the chamber It will be connected directly with the reservoir 21, in the manner described above, and fluid displaced from the upper end of chamber 04 will flow to the reservoir. In the event there has been any fluid displaced or otherwise lost from the connected ends of chambers 84 and Cl it will be replaced through a checkvalve controlled passage in formed in piston 85. This passage receives check valve I24 which is of the poppet type, being held in a normally closed position by a coil spring I25. From the foregoing it will be seen that reciprocat'ory movement of piston 31 will be transmitted to the ram 91 and platen 9'. If the valve 24 is set to cause the piston 21 to execute short strokes the ram 91 and platen 9i will be caused to execute similar strokes at higher tonnage.

One of the features of the invention resides in providing a second relief valve I26, the inlet of which is connected with the upper end of the power cylinder 29. The control chamber of this relief valve is connected by line I21 with ports I in sleeve ili. Normally ports iili are blocked by spool i I l but when this spool moves under the influence of pressure in the connected ends of chambers 84 and It, groove 2 will establish communication between ports I06 and I01, thus connecting the control chamber of relief valve I26 with reservoir 21. Relief valve I26 may then respond to the pressure in the upper end of cylinder 2! to vent fluid from the same to the reservoir 21. It will be seen that relief valve I25 may therefore be set at a lower pressure than relief valve ll so that the pressure developed by the attachment may be readily controlled. When the spool ill returns to its normal position, the

control chamber of the second relief valve l26 will again be blocked from the reservoir permitting the first relief valve to control the pressure existing in the system.

While the form of embodiment of the present invention as herein disclosed constitutes a preferred form, it is to be understood that other 1 forms might be adopted, all coming within the scope of the claims which follow.

I claim: 1 v

1. In a hydraulic system, a source of fluid pressure; a power cylinder; a piston disposed for movement in said power cylinder; control means between said pressure source and said cylinder to cause reciprocatory movement of said piston; a second cylinder; a second piston disposed for movement in said second cylinder, said pistons being connected for movement in. unison; a third cylinder; a third piston mounted for movement in said third cylinder; a fluid conductor connecting one end of said second and third cylinders; fluid conducting means connecting the opposite ends of said second cylinder; valve means in said last-mentioned fluid conducting means for normally preventing communication between the ends of said second cylinder; means responsive to fluid pressure in the connected ends of said second and third cylinder for actuating said valve means; and relief valve means for v 8 4 controlling the eiiective pressure in the first cylinder when communication between the ends of the second cylinder is established.

2. In a hydraulic system, a source of fluid pressure; a powercylinder; a piston disposed for movement in said power cylinder; control means between said pressure source and said cylinder to cause reeiprocatory movement of said piston; a second cylinder; a second piston disposed for movement in said second cylinder. said pistons being connected for movement in unison; a third cylinder; a third piston mounted for movement in said: third cylinder; a fluid conductor connecting one end of said second and third cylinders; fluid conducting means connecting the opposite ends of said second cylinder; valve means in said last-mentioned fluid conducting means for normally preventing communication between the ends of said second cylinder; means responsive to fluid pressure in the connected ends ofsaid second and third cylinder for actuating said vaive means; and relief valve means for controlling the effective pressure in the flrst cylinder when communication between the ends of the second cylinder is established; said relief valve being normally inoperative and rendered operative by said fluid pressure responsive means simultaneously with the establishment oi communication between the ends of said second cylinder.

3. Hydraulic apparatus comprising a source of fluid pressure; a double-acting power cylinder having a piston; control valve means between said pressure source and power cylinder, said valve means being operative to cause the repeated reciprocation of the piston in said power cylinder over a fraction of the normal stroke thereof; a second piston connected for movement with the first-mentioned piston; a second cylinder receiving the second piston; a third cylinder; means establishing communication between one end of said second and third cylinders; and means responsive to fluid pressures in the connected ends of said second and third cylinders ior establishing communication between the ends of said second cylinder.

4. Hydraulic apparatus comprising a source of iiuid pressure; a double-acting power cylinder having a piston reciprocable through a normal stroke; control valve means between said pressure source and power cylinder, said valve means being operative to cause repeated reciprocations of said piston through a fraction only of the normal stroke; a second cylinder; a second piston disposed for reciprocation in said second cylinder, said second pistonbeing connected for movement in unison with said first piston; means for establishing communication between the ends of said second cylinder when said second piston is moving in one direction only; a single-acting power cylinder communicating with one end of said second cylinder; and means responsive to the pressure in the communicating ends of said second and third cylinders to establish communication between opposite ends of said second cylinder when said second piston is moving in the opposite direction. 5. Hydraulic apparatus comprising a source of fluid pressure; a double-acting power cylinder having a piston; means for controlling the operation of said piston including a fluid pressure reversing valve; means operative upon initial return movement of said piston for applying fluid pressure to said reversing valve to cause forward movement of said piston; a second piston connected with said first piston for movement in unison therewith; a second cylinder receiving said second piston; a third cylinder in communication with one end of said second cylinder; a third piston disposed for reciprocation in said third cylinder; resilient means yieldably resisting movement of said third piston in one direction in said third cylinder; and valve means responsive to predetermined fluid pressure in said third cylinder to establish communication between opposite ends of said second cylinder.

6. Hydraulic apparatus comprising a source of fluid pressure having a reservoir; a relief valve communicating with said pressure source; a power cylinder having a piston and ram; control mechanism between said pressure source and said power cylinder, said mechanism being operative to cause the reciprocation of said piston; a second power cylinder having a second ram; a third cylinder having a third piston and a ram aligned with and engaged by the ram of said first-mentioned power cylinder; fluid conducting means connecting the ends of the second and third cylinders opposite the ram ends; a valve mechanlsm having a casing with a plurality of ports;

fluid lines leading from ports in said valve casing to opposite ends of said third cylinder and from other ports to said reservoir and to the end of said first cylinder opposite the first ram; a second relief valve in the line leading to said first cylinder; and a valve member in said casing, said valve normally establishing communicationbetween the ram end of said third cylinder and said reservoir andpreventing operation of said second relief valve, said valve being responsive to fluid pressure inthe end of said third cylinder opposite its ram to simultaneously interrupt such communication, establish communication between opposite ends of said third cylinder and render said second relief valve efiective to control the pressure in the end of said first cylinder opposite the ram thereof.

'7. Hydraulic apparatus comprising a source of fluid pressure including a reservoir; a relief valve communicating with said pressure source; a pair of aligned power cylinders having pistons and 10 rams, the latter being connected to cause said pistons to move in unison; means for controlling fluid flow from said source to opposite ends of the first of said pair of cylinders to effect reciprocation of both pistons; a third power cylinder having a ram; a conductor connecting an end of the second of said pair of cylinders with one end of the third cylinder; a second relief valve connected with the end of the first of said pair'of cylinders opposite the ram thereof; means responsive to fluid pressure in said third cylinder for establishing communication between the ends of the second cylinder of said pair and rendering said second relief valve operative, said means having a casing with a plurality of ports two of which are connected with the ends of said second cylinder, another being connected with said reservoir and another being connected with the outlet of said second relief valve; and a spool disposed for movement in said casing, said spool normally preventing communication between the ports connected with the ends of said second cylinder and between the outlet of said second relief valve and said reservoir and establishing communication between the ram end of said second cylinder and said reservoir, a predetermined increase in pressure in the third cylinder serving .to move said spool to simultaneously interrupt the communication between said second cylinder and said reservoir, establish communication between the ends of said second cylinder and connect the outlet of said second relief valve with said reservoir.

CECIL E. ADAMS.

REFERENCES orrEn The following references are of record in the file of this patent:

UNITED STATES PATENTS Dodge Jan. 25, 1944

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