US2732738A - Hydraulic press - Google Patents

Description

Jan. 31, 1956 P. KRAUSE 2,732,733

HYDRAULIC PRESS Filed Dec. 22, 1951 4 Sheets-Sheet 2 IN V EN TOR. GER/W980 E AA'n us:

BY 7 %JMW 1956 G. P. KRAUSE 2,732,738

HYDRAULIC PRESS Filed Dec. 22, 1951 4 Sheets-Sheet 3 INVENTOR. GER/YARD A M74055 HTT X I VS Jan. 31, 1956 5. P. KRAUSE HYDRAULIC PRESS 4 Sheets-Sheet 4 Filed Dec. 22, 1951 iikwkl United States Patent press, Incorporated, New York, N. Y., a corporation of Delaware Application December 22, 1951, Serial No. 262,963 Claims. 01. 784:)

This invention relates to a press suitable for piercing a billet and particularly to one having a continuous movement of certain of the parts operating on the billet during the piercing operation. t I

In the extrusion of tubes or the like, a billet with an aperture therethrough can be placed into a suitable container in an extrusion press, there being an appropriately shaped extrusion die at one end of the container. A mandrel is advanced through the aperture in the billet and into or relative to the die as needed. The extrusion plunger or stem then is moved against the billet and force applied so as to extrude metal through said die. In-some operations, it particularly is desirable to provide billets properly dimensioned and having concentric apertures. This problem especially is of importance when high temperature metals are involved, such as stainless steel, alloy steels, and the like.

One of the objects of the invention is to provide an arrangement wherein the billet can have successive operations performed thereon with a substantially continuous movement of the operating or forming parts so as to produce a pierced or otherwise shaped billet of the desired dimensions.

A still further object of the invention is to provide a control system for a piercing press which will control the operation of the successive movements of the various parts as a billet is pset and pierced or otherwise treated.

In one aspect of the invention, a hydraulically operated press may have a billet container into which a billet can be placed. in order to accurately size the billet, it is first desirable to perform an upsetting operation thereon so that it completely fills the billet aperture in the container. An upsetting tool having a diameter substantially that of the aperture in the billet container can be employed and the upsetting tool may be moved by a crosshead or suitable movable means releasably connected to a main hydraulic motor. A piercing plunger or tool is arranged to be reciprocable within an aperture at the end of said upsetting tool, said piercing tool being carried by a second crosshead or other guide means directly connected to the main motor. The two crossheads can be releasably locked together by some suitable means such as a hydraulic ram and cylinder arrangement, although other types of locking means can be used.

With a billet in the container at proper temperature, the hydraulic locking or coupling means is arranged so that upon operation of the main hydraulic motor, the two crossheads will move together carrying the upsetting tool and piercing tool against the billet. For the upsetting operation, the piercing tool is adjusted to be flush with the end of the upsetting tool. The force applied by the main hydraulic motor will cause the billet to be upset so that it will become the same diameter as the billet container aperture.

The press can be controlled so that when the predetermined required pressure is reached to have completed upsetting the billet in the container, thehydraulic lock between the two crossheads will be unlocked. inasmuch as 2,732,738 Patented l. 31, lose pressure is still being exerted by the main cylinder on the piercing tool crosshead, the piercingtool will continue its movement into the billet in a piercingoperation, the piercing plunger moving relative to theupsetting tool. The crosshead carrying the upsetting tool can at this time, or before, or thereafter, have hydraulic means connected thereto so as to raise it away from the face of the billet. The movement of the piercing'plunger is continuously downward and it will enter the billet while it is closely guided by the upsetting tool, thus insuring concentric'ity of the aperture being pierced.

Below the billet in the container, an apertured collar or seat means can be located, said apertured seat means having been placed in the container ahead of the billet. The aperture therein is made substantially the same diameter or size as the piercingtool. A back-up plunger and the aperture in said seat means is aligned with said -pierc ing tool. The backup plunger is movable by a hydraulic motor so that its upper end is flushwith the top of said seat means and closely adjacent or contacting the bottom of the billet. The seat means'and back-up plunger thus serve as the bottom wall of the billet container during the major part of the upsetting and piercing operation.

At a predetermined point in the downward movement of the piercing tool, when a predetermined thickness of metal remains unpierced between the tool and the backup plunger, suitable mechanism can be operated to move the back-up plunger downwardly with the piercing tool, thus punching or removing a plug from the billet. The back-up plunger is moveddownwardly far enough to per mit proper movement of the-parts thereafter.

. The billet container can be mounted on a reciprocable or slidable billet container carrier assembly for the purpose of moving the container out of alignment with the press tools, the back-up plunger being moved downwardly out of the way or" said carrier upon which the billet container is mounted. Before movement of said slidable carrier assembly, the piercing plunger can be moved upwardly so as to free it from the billet container. Suit; able mechanism then can be provided to slide said carrier assembly with the billet container thereon out of alignment with the tools and thereafter to strip the pierced billet and seat-means from the billet container, 21 new seat means and billet then being fed into the container.

.Ihe slidable carrier assembly can have mounted there on a cooling fluid reservoir which is moved so as to be positioned under :the piercing plunger. When the cooling means. is aligned with the piercing plunger, control apparatus can be operated to cause the piercing plunger to move relative to said fluid reservoir so as to cool the tool.

The upsetting operation is carried out with the bottom of the billet container closed by the back-up plunger. The greatest part of the piercing operation is carried out with a closed billet container, the back-up plunger not starting to open said bottom end until the piercing plunger is relatively near the bottom of the billet. Various automatic control means can be used to cause the parts to move as desired in a continuous manner, the control means being entirely automatic or being semi-automatic.

In the drawings: I

Fig. I is a sectional elevation taken generally along the line 1 1 of Fig. 4 v

Fig. 2 is a sectional elevation taken generally along the lines 22 of Figs. 3 and 4 and including parts of the unloading mechanism, some of the parts being omitted or broken away in the interest of clarity.

Fig. 3 is a sectional view through the upper crosshead taknalong'the line 33 of Fig. 2..

Fig. 4 is asec-tional view through the lower crosshead taken along the line of Fig. 2 t

Fig. 5 is a fragmentary sectional view showing the tool relationship at the completion of the upsetting operation.

Fig. 6 is similar to Fig. except that the piercing tool has just started its downward movement relative to the upsetting tool. V Fig. 7 is generally similar to Figs. Sand 6 and shows the piercing tool just before the back-up plunger starts to move downward.

. Fig. 8 is generally similar to Fig. 7 except that .it shows the piercing plunger and back-up plunger after the billet has been pierced.

Fig. 9 is a schematic control diagram of one form of control circuit which can be used, the parts being shown schematically as discussed hereafter.

The press consists generallyof a frame having a main operating fluid motor 21 at the top thereof, said motor having a ram 22 therein connected with an upper crosshead or platen 23. The shank 24 of said ram is engaged in aperture 25 of the upper crosshead 23. Upper crosshead 23 may have coupling or hydraulic lock rams 26, said rams being located in diagonal relationship to the centerlines of crosshead 23 (Figs. 3, 4) and being connected at 27 to said upper'crosshead 23. The ram 22 can have a piercing plunger or tool 32 suitably connected therewith so as to be moved directly thereby, either through the crosshead 23 or by plunger 32 being di rectly connected to the ram 22. Rams 26 cooperate with hydraulic cylinders 28 mounted in the lower crosshead or platen 29. The lock means may be arranged other than diagonally and the ram and cylinders can be reversed, Also, a mechanical lock means (not shown) can be used in place of the hydraulic lock although the latter is preferred.

Rams 26 may have fluid passages 30 therein controlled by suitable lock control valve means, one form of which will be described in conjunction with the control arrangement. The lock control valve means can be arranged to be in closed position so that a hydraulic lock is provided between crossheads 23 and 29 during the upsetting operation, movement of upper crosshead 23 downwardly then moving the lower crosshead 29 with it.

A billet upsetting tool 31 can be mounted on crosshead 29, said tool having an aperture 33A therethrough for the piercing tool or plunger 32. The operating end 33 of said piercing tool is enlarged, said enlarged portion being relatively closely guided by apertures 33A in upsetting tool 31. During initial movement, and while the upsetting tool is performing an upsetting operation on the billet, the end of the piercing tool is held flush with the end of the upsetting tool 31 so as to operate as a part thereof during the billet upsetting operation.

Billet container 34 has a suitably dimensioned aperture 35 therein for receiving the billet to be pierced. The billet container is slidably mounted on a fixed table or slide 36 carried by the frame of the machine, the billet container 34 being mounted on the slidable billet container carrier assembly, indicated generally by 37. Longitudinally extending support or rail 38 is mounted at 39 (Fig. 2) on the machine frame. The billet container 34 has an annular portion 34A (Fig. 1) which engages in the depression 343 of the container base 37C, the base 37C in turn being fastened to the shifting table 37D.

The base 37C is guided on rail 38 as the container assembly is reciprocated by the hydraulic motor 47. 7 It will be seen that removable plug or seat means 40,.placed in the bottom of the billet container aperture 35, will slide along the top of rail 38 as the carrier assembly 37 is reciprocated.

Back-up plunger 41 is conencted to a hydraulic motor arrangement indicated generally at 42 so that the upper surface of 41 is at the top of plug in the billet container aperture during the first part of the operation as will be described hereafter. As will be explained later,

1 back-up plunger 41 is movable downwardly'to a point below the table 36 (as shown in dotted lines, 43), so that 56 has pullback or return hydraulic motors 65 connected 1 the billet container slide asembly 37 can be slid therei over.

Back-up plunger operating arrangement 42 may have a crosshead 56 carrying hydraulic cylinder 57. Hydraulic cylinder 57 is reciprocable by ram 58 fixedly mounted (not shown) on the machine frame. Crosshead 56 has an upper surface 60 on either side of the center of the machine, said surface being in abutting relationship with the bottom surface of nut 61 adjustably mounted on operating rods 62 when the back-up plunger is in an upper position. Operating rods 62 have upper members 63 fastened thereto or integral therewith, said upper members 63 being slidably mounted in apertures in the lower crosshead 29. The upper ends of members 63 may have pads or saddles 64 thereon, said pads being exchangeable or,

being adjustable in height by means of shims. Crosshead therewith.

Describing operation of the parts to this point, assume that the billet to be pierced is in position in billet container 34 located under the upsetting tool 31 and piercing tool 32. Pressure is aplpied to hydraulic cylinder 21, the hydraulic lock valve mechanism being arranged so that the lock is in locked condition as crosshead 23 moves downwardly causing crosshead 29 to move therewith. This will move upsetting tool 31 and piercing plunger 32 downwardly together and will exert an axial upsetting pressure on the billet so as to upset it and cause its walls to completely contact the billetcontainer walls of aperture 35. When the pressure in main cylinder 21 reaches a predetermined amount, control means can be operated to release the hydraulic lock mechanism and thus permit the lower crosshead 29 to move relative to the upper crosshead 23. In Fig. 5 can be seen the relationship of the parts at the time the upsetting operation is complete.

Pressure can be admitted to the return cylinders 45 so as to move the lower crosshead 29 upwardly a short distance and thus remove the upsetting tool 31 from contact with the top of the billet to be pierced as is seen in Fig. 6. This will permit the billet metal to flow upwardly in the container as the piercing operation takes place. In the meantime, piercing tool 32 will continue its movement downwardly under urgence of the uninterrupted pressure applied to the main hydraulic motor 21, the tool having entered the billet while it was still being guided accurately by the upsetting tool as illustrated in Fig. 6. The piercing tool 32 thus is seen to move continuously downwardly in the operation.

As the upper crosshead 23 moves downwardly relative to the lower crosshead 29 as the billet is being pierced, and the parts reach the relative positions illustrated in Fig. 7, surfaces 66 (Fig. 1) of the upper crosshead will come into contact with pads 64 which in turn will move their respective rods 63 and 62 downwardly to move back-up plunger crosshead 56 downwardly. This is because of the contact of nuts 61 with surfaces 60 of the crosshead 56. Thus, at a predetermined point or distance of the piercing plunger 32 from the back-up plunger 41, the back-up plunger will start its movement downwardly, thereby carrying a pierced scrap piece P therebetween.

Members 63 will move downwardly until the surfaces 67 thereof meet surfaces 68 on the machine. At this point, the back-up plunger is below the plug 40 and the scrap piece is therebetween. After the crosshead 56 has been moved by members 63 and 62, suitable control circuits can be operated so as to cause operation of pullback motors to move the back-up plunger 41 to position 43 below the slidable container assembly 37. Members 63 are slidable in apertures 63A in the lower crosshead 29.

Lower crosshead pullback hydraulic motors 44 have cylinders 45 located on the frame of the machine, rams 46 being mounted so as to contact or to be connected to the lower crosshead 29.

After the piercing hasbeen completed and the piereing plunger moved up to its top position out of thebillet container and back-up plunger has been moved to its lowest position, the slide operating motor 47 can be activated to move the slide assembly 37 with the billet container 34 thereon to an ejector station. The pierced scrap P can be carried along with movement of shifting table 37D and will then drop out of the opening in 37D and into any suitable receiving means. In Fig. 2, the ejector plunger 48 is arranged to be moved upwardly against pusher 48A for stripping a pierced billet from the billet container.

Cooling means 50 can be carried on the slide 37 into alignment with the piercing tool 32 whichcan be moved downwardly so that the tool can be cooled. Thereafter, crosshead 23 can be moved upwardly and the tool retracted.

The upper crosshead 23 is mechanically connected to the lower crosshead 29 by means of tie rods 52, said tie rods being held from longitudinal movement in the lower crosshead by nuts 53, 54. The connection of tie rods 52 to the upper crosshead is by means of nuts 55 on the upper side only, so that relative movement of the tie rod in one direction relative to the upper crosshead is permitted. This arrangement is used so that the lower crosshead 29 can move upwardly relative to the upper crosshead, yet so that when the upper crosshead 23 is moved upwardly during its return movement, nuts 55 will serve to limit the movement relative to lower crosshead 29.

Various types of controls can be used, one being schematically illustrated in Fig. 9. In Fig. 9, the press illustrated in Figs. 1 to 8, inclusive, is shown generally in front elevation at A and an enlarged fragmentary side view is found at B, the side view showing the lower portion of the press including the ejector station. Certain of the limit or operating switches are schematically illustrated in their general locationon the press, and in the interest of clarity, the same switch with its essential operating elements is shown elsewhere on the drawing dot-dash lines connecting the same element.

The source of high pressure liquid is connected to the main operating motor 21 through the main cylinder control valve 112. Servo-motor valve operator 110 may have a handle 111 which is moved inwardly toa press position so as to operate the main control valve 112. First, valve 112R is opened to drain return cylinders 45 through line 129, control valve 127, line 2&0, valve 112R, and line 2%2 to a suitable storage tank (not shown). The press ram 22 will start moving downwardly and prefill valve 154 will open to admit prefill pressure into the main motor 21. Thus, prefill pressure is utilized during the approach stroke. I

Valve 1121 will be opened thereafter so as to admit main or accumulator pressure to the main motor 21 through line 115.

The hydraulic lock by-pass valve 116 is closed by pressure from the accumulator through line 116A,- valve 129, and line 1163 so as to lock the upper crosshead 23 with the lower crosshead 29, thus transmitting movement of ram 22 to both the piercing tool 32 and the upsetting tool 31 so as to perform the upsetting operation.

When a predetermined pressure is reached, as indicated by control gauge 117, a conventional timer means 117A will be energized to produce electric control currents to operate the return cylinder 45 control and the coupling cylinder control as will be described hereafter. Preferably two timers are used, these timers being of any suitable construction where the contacts are closed a predetermined time after they are activated.

Energization of solenoid 118 will move valve 119 upwardly in its body and will serve to operate hydraulic lock by-pass valve control means 120 to permit flow from 1163 through valve 166 to the tank. This will open the hydraulic lock by-pass valve 116 and allow flow of fluidfroin the lock cylinders 28 and, thus release the connection between upper crosshead 23 and lower crosshead 29. i r

According to the particular s'ettin'gof the timers, control means 121 can complete a'nelectric circuit to solenoid 122 so as to actuate the return cylinder control valve 123 for operating return cylinders, 45 to lift the upsetting tool at the desired time on the billet as inFig. 6. Movement of the control valve -123,to its upper end will connect the control line 124 through line 125 with the servo-motor 126. This will in turn operate .control valve 127 to furnish pressure from line 128 through line 129 to the returrl cylinders 45. and thus move the lower crosshead 29 upwa'rd a predetermined distance to raise upsetting tool 31 off the face ofthe billet;

In the meantime, pressure has ,uninterruptedly been supplied to main cylinder 21 so that piercing tool 32.will continue its downward movement intd the. billet. when the upper crosshead 23 contacts operating rods 63 as described previously, back-up plunger crosshead 56 will be moved downwardly.

At this time, back-up plunger 41 is in its upper position since earlier during the cycle, lower crosshead '29 closed limit switch 189 which through the closed "switch 148 energized solenoid 131a on back-up cylinder control valve 132a as shown in Fig. 9. The open push button 150, which serves for manual control, is bypassed. In this position, air pressure is connected to servo-motor 133 so as to open supply valve of back-up cylinder control valve 134a and keep exhaust valve 134 closed. Thus pressure is admitted from the accumulator through the open supply valve 135 and line 181 to the back-up cylinder 57.

The pair of solenoids 131 and 131a are connected to the circuit in such a manner that after one solenoid has been energized, it will remain in this condition until the other solenoid is energized. Details of these connections are not shown in the drawing. It may be mentioned here that the pairs of solenoids operated by push buttons 139, and 144-, are connected to the circuit in a corresponding manner. When the back-up' plunger crosshead 56 reaches limit switch 130, solenoid 131 on the back-up cylinder control valve 132 will be energized through closed switch 130 and solenoid 131a will be deerlergized so as to connect air pressure to back-up plunger cylinder control valve motor 133. This will serve to open exhaust valve 134 of back-up cylinderco'ntrol valve 134A and close supply valve 135, thus permitting pressure to be exhausted from the back-up plunger cylinder 57 through valve 134 and line 202 to a tank (not shown). At this time, constant pressure from line 136 will be exerted on the back-up plunger return motors 65 so as to move the back-up plunger 41 downwardly and below the table position as previously described. V v 7 Limit switch 137 will be contacted when the back-up plunger arrangement reaches its lower limit of travel and this will serve to close a circuit through the normally closed ejector, plunger limit switch 138 to the shifting table control buttons 139, 140, the piercing plunger and crosshead 23 having been previously moved upwardly so as to close switch 161. With this circuit completed, the appropriate shifting table control button can be actuated so as to operate the controlvalves 141 controlling pressure to the shifting table hydraulic control valve 142 which in turn controls operating pressure to the slide assembly operating motor 47. When the shifting table assembly 37 reaches its right or ejector position, limit switch 143 will be actuated soas to supply power tothe ejector cylinder control buttons 144, 145. Thesecontrol buttons actuate the ejector cylinder pilot valves 146 which in turn operate the servo-motor 147 to control fiuid to the ejector cylinder 49. It is seen that the table cannot be moved unless the back-up plunger 41 is in its lower position and the ejector cannot be moved upwardly until the billet container slide assembly is properly positioned over the ejector. Opening of limit switch 148 at the left end of the billetcontainer slide assembly disables the back-up plunger cylinder push buttons 149, 150 so that the back-up cylinder cannot be manually operated thereby. When the slide assembly 37 is in its right hand position (Fig. 9), the cooling container 50, as described for Fig. 2, will be under the piercing tool 32. At this time, mandrel cooling push button 151 can be actuated to cause the piercing tool 32 to move downwardly into the cooling fluid pot. As the piercing tool moves downwardly, limit switch 156 will be closed which will energize the cooling fluid control valve 152 so as to cause cooling fluid to be directed onto the piercing tool.

When it is desired to return the piercing tool to its upper position, valve handle 111 can be moved to the left (Fig. 9) which will operate main valve 112. Carn 158 will close valve 157 and open valve 159 so that pressure will be admitted to'pilot cylinder 154 through line 160. Prefill valve 154A will be positively opened thereby to permit fluid to exhaust to the prefill tank as pressure admitted to the coupling cylinders 28 raises upper crosshead 23.

When limit switch 161 is operated to closed position, as in Fig. 9, by crosshead 23 reaching its upper position, valve 127 will be returned to the position shown in Fig. 9.

Valve 164 will take care of replenishment of fluid in the coupling cylinders when needed and at appropriate times when both crossheadsmove downwardly to prevent relative movement between piercing and upsetting tools. Valve 165 is arranged so as to prevent intensified pressure from the coupling cylinders getting into the main control. Valve 166 is provided to prevent flow of liquid into the tank under emergency conditions, valve 166 being operable by pressure'in line 160 to cut-ofl? possible flow from valve 120 and valve 116. Also, various valves can be operated manually as indicated in Fig. 9.

It is to be understood that various types of control arrangements and details can be used, and that variations can be made in the constructions illustrated without departing from the spirit of the invention except as defined in the appended claims.

What is claimed is:

1. In a piercer press, or the like, the combination including a hydraulically operated tool moving means, a billet container having an aperture therethrough, an upsetting tool, a piercing tool movable relative to said upsetting tool, connections between said piercing tool and said hydraulically operated tool moving means, hydraulic coupling means releasably locking said tools together to move said tools in unison by said hydraulically operated tool moving means when the hydraulic coupling means is locked, means releasing fluid from said hydraulic coupling means to unlock the same upon completion of upsetting the billet so that said upsetting tool movement will be stopped while said piercing tool uninterruptedly continues its movement downward, a back-up plunger in the bottom of the aperture in said billet container closing the 'same, and means moving said back-up plunger downwardly when said piercing tool is a predetermined distance thereabove so as to remove a scrap piece from the bottom of the billet.

V 2. In a piercer press, or the like, adapted to operate an upsetting tool and a piercing tool, the combination including a hydraulically operated tool moving means operatively connected to one of said tools, a releasable locking means connecting said tools together when locked so that said tools will be moved in unison by said tool moving means, pressure controlled means responsive to the pressure in said hydraulically operated tool moving means, and means connecting said pressure controlled means with V 8 said releasable locking means releasing the same when a predetermined pressure is reached as said tools are moved together into contact with work, so that one tool will stop and the other will uninterr'uptedly continue its movement.

under the influence of said tool moving means.

3. In a piercer press, or the like, adapted to operate an upsetting tool and a piercing tool, the combination including a hydraulically operated tool moving means operatively connected to one of said tools, a releasable locking means connecting said tool-s together when locked so that said tools will be moved in unison by said tool moving means, pressure controlled means responsive to the pressure in said hydraulically operated tool moving means means connecting said pressure controlled means with said releasable locking means releasing the same when a predetermined pressure is reached as said tools are moved together into contact with work, so that one tool will stop and the other will uninterruptedly continue its movement under the influence of said tool moving means, and means moving said stopped tool away from the work as the other tool continues its movement into the work.

4. In a piercer press, or the like, adapted to operate an upsetting tool and a piercing tool, the combination including a hydraulically operated tool moving means operatively connected to one of said tools, a releasable hydraulic locking means connecting said tools together when locked so that said tools will be moved in unison by said tool moving means, means automatically replenishing said locking means with fluid when in locked position, pressure controlled means responsive to the pressure in said hydraulically operated tool moving means, and means connecting said pressure controlled means with said releasable locking means releasing the same when a predetermined pressure is reached as said tools are moved together into contact with work, so that one tool will stop and the other will uninterruptedly continue its movement under the influence of said tool moving means.

5. In a piercer press, or the like, the combination including a billet container having an aperture therethrough, an upsetting tool, a piercing tool movable relative to said upsetting tool, tool moving means moving said piercing tool toward a billet in said billet container, hydraulic coupling means releasably locking said tools together so that they will be moved in unison by said tool moving means when the coupling means is locked, means unlocking said coupling means so that said upsetting tool movement will be stopped While said piercing tool uninterruptedly continues its piercing movement, a back-up plunger in the bottom of the aperture in said billet container closing the same, and means moving said back-up plunger downwardly when said piercing tool is a predetermined distance thereabove so as to remove a scrap piece from the bottom of the billet.

References Cited in the file of this patent UNITED STATES PATENTS 1,352,911 Paque Sept. 14, 1920 2,001,902 Engelbertz May 21, 1935 2,128,705 Hatebur Aug. 30, 1933 2,215,943 Trant Sept. 24, 1940 2,299,105 Muir Oct. 20, 1942 2,358,765 Stadlin Sept. 19, 1944 2,417,569 Rice Mar. 18, 1947 2,593,730 Cornell Apr. 22, 1952 FOREIGN PATENTS 433,258 Great Britain Aug. 12, 1935

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