US3563136A - Variable force hydraulic press - Google Patents

Variable force hydraulic press Download PDF

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Publication number
US3563136A
US3563136A US799309A US3563136DA US3563136A US 3563136 A US3563136 A US 3563136A US 799309 A US799309 A US 799309A US 3563136D A US3563136D A US 3563136DA US 3563136 A US3563136 A US 3563136A
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Prior art keywords
ram
piston
fluid
housing
chamber
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Expired - Lifetime
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US799309A
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English (en)
Inventor
Raymond L Valente
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Manco Manufacturing Co
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Manco Manufacturing Co
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B30—PRESSES
    • B30B—PRESSES IN GENERAL
    • B30B15/00—Details of, or accessories for, presses; Auxiliary measures in connection with pressing
    • B30B15/16—Control arrangements for fluid-driven presses
    • B30B15/161—Control arrangements for fluid-driven presses controlling the ram speed and ram pressure, e.g. fast approach speed at low pressure, low pressing speed at high pressure
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B30—PRESSES
    • B30B—PRESSES IN GENERAL
    • B30B15/00—Details of, or accessories for, presses; Auxiliary measures in connection with pressing
    • B30B15/16—Control arrangements for fluid-driven presses
    • B30B15/22—Control arrangements for fluid-driven presses controlling the degree of pressure applied by the ram during the pressing stroke

Definitions

  • a variable force hydraulic press of the general type which includes a frame having albase portion with a support surface, and a head portion spaced above said base portion.
  • the head portion has a ram arrangement contained therein, whereby the ram may be reciprocated toward and away from the base portion.
  • Said ram arrangement includes a housing and a pistonlike ram element slidably positioned within said housing.
  • the ram has first and second piston surfaces facing in the same direction and cooperating with said housing to define first and second piston chambers.
  • Conduit means are provided in said housing to achieve a fluid path from each said chamber to the exterior thereof, said fluid paths being associatedwith a source of fluid under pressure and control means. Accordingly, a selective app1ication of fluid pressure to either or both said chambers may be attained, with the force exerted by said ram varying according to the total piston surface area subject to said fluid pressure.
  • the present invention relates to hydraulically operated press apparatus. More particularly, this invention is concerned with a variable force hydraulic press usable in conjunction with die units to perform various metal fabricating operations.
  • Presses of" the type to which the present invention relates normally comprise a frame having a supporting surface for a die unit and a head portion spaced therefrom by vertical standards.
  • These die units include an anvil section which rests upon and is affixed to the supporting surface of the frame, and a blade element that is slidably engaged therewith; said anvil section normally being notched to provide a recess or channel for supporting a section of stock material.
  • the head portion of the press houses a hydraulically operated reciprocating ram arrangement, to which is affixed the blade member of a die unit.
  • the aforementioned presses are employed in metal fabricating shops for a wide variety of purposes.
  • said units may be used to shear stock material of various shapes, such as angle irons, flat stock, square tubing, and square or round stock.
  • these presses may be adapted for notching and coping of sheet stock, as well as bending of stock material of various shapes and sizes.
  • these press units may come equipped with a miter block so that miter cuts may be effected if desired.
  • a shearing press capable of exerting a total force of approximately 190 tons may have a cycle time of approximately 6 to 7 seconds, while a press rated at 130 tons may have a cycle time of only 4 to seconds, Still further, presses rated at 60 tons or less have a cycle time of only 3 to 3%seconds.
  • the term cycle is employed to designate the full movement of the ram, i.e., the operating and return stroke.
  • variable force hydraulic press comprising a housing and a pistonlike ram element slidably positioned therein, said ram having first and second piston surfaces cooperating with the internal portions of said housing to define first and second piston chambers.
  • the housing has a plurality of passageways formed therein communicating with said chambers, such that they may be associated with a source of fluid under pressure. Accordingly, by utilization of control means, fluid under pressure may be selectively applied to either one or both said chambers so that the pistonlike ram element may be moved on the down or operating stroke with a force proportional to the total piston surface area subjected to said] fluid pressure.
  • FIG. 1 a shearing unit of the type to which the present invention relates is shown in FIG. 1 and designated generally 10.
  • Said unit 10 comprises a frame 12 which includes a base portion 14 and a head portion 16 spaced above said base portion by the vertical standards 18.
  • the unit 10 is designed to ⁇ receive a die assemblage 20 which is supported on the upper surface 21 of the base portion 14.
  • Die assemblage 20 is comprised of a first die or blade member 22 and cooperating anvil portion 24.
  • the blade member 22 and anvil portion 24 are assembled and interconnected so that they may be handled as a unit, with the blade member 22 being slidably received between spaced sections of said anvil portion.
  • the upper or head portion 16 of the unit 10 includes a hydraulically operated ram arrangement, designated generally 30.
  • This arrangement 30 includes a ram member 32 that is adapted to be reciprocated along a path perpendicular to the base surface 21.
  • the ram 32 is pro- I vided with a T-shaped slot 36 which receives the upper correspondingly shaped portion 38 of the blade member 22.
  • said blade is operatively, but removably, connected with the ram 32 and .upon affixing of the anvil portion 24 to the base surface 21 said blade is adapted for movement relative thereto.
  • the anvil 24 includes a V-shaped portion or notch 40 within which is supported the stock material, for engagement by the reciprocating blade 22.
  • the shape of the notch will vary depending upon the particular stock material to be processed. Accordingly, when the ram is raised to the uppermost limit of its stroke the blade 22 will assume the position illustrated in FIG. 1, thus permitting stock material to be engaged under said blade the notch 40 for shearing.
  • the amount of force required to perform 22 and supported by a particular operation depends upon the cross-sectional area of the billet or stock material to be processed. Accordingly, where billets of relatively small cross-sectional area are employed the force required for shearing is small; on the other hand, where the cross-sectional area of the billet is large, correspondingly the force required for shearing will be greater.
  • a fabricator in order for a fabricator to employ only the required amount of force for a fabricating operation, it was necessary to have more than one shearing unit. Or, if this was economically unfeasible, it was necessary that a fabricator determine the maximum tonnage he would need, and then purchase a unit of sufficient capacity. This latter course of action, while less expensive resulted in wasted production time, as the cycle time for a large unit will remain relatively constant irrespective of the cross section of a billet.
  • FIG. 2 there is illustrated a variable force hydraulic press or ram arrangement 30 which provides the metal fabricator with a certain degree of flexibility in his choice of operating force, in that he may select a force commensurate with the job at hand.
  • FIG. 2 illustrates the upper or head portion 16 of the press 10.
  • this head portion 16 includes an outer covering or casing 42 which overlies the hydraulic ram apparatus of the press 10.
  • the standards 18 support or carry a base plate 44 which is apertured at 46 and which has a ram housing assembly 48 positioned thereon in overlying relationship with respect to said aperture 46.
  • a bushing or insert 50 Positioned in said aperture 46 is a bushing or insert 50 which provides a bearing surface for the pistonlike reciprocating ram member 32.
  • the ram member 32 is slidably received within the outer portion of said housing assembly 48 and extends therefrom toward the support surface 21.
  • the lowermost portion of said ram 32 as was mentioned previously, has the T-shaped slot 36 formed therein for reception of the correspondingly shaped portion 38 of blade member 22.
  • various fluid passage means are employed to provide a path of communication from a source of fluid under pressure (not shown) to the interior of said ram housing 48 whereby the piston arrangement 32 may be reciprocated toward and away from the supporting surface 21, as discussed.
  • the hydraulically operated ram member 32 of the present invention is designed such that there are provided two pistonlike surfaces which may be individually or jointly subjected to fluid pressure in order to obtain a variation in the working or operating force.
  • the housing assembly 48 includes an outer housing member 58 and an inner housing core section 60 fixedly attached thereto. Said member 58 and core section 60 cooperate with the ram arrangement 32 to define a plurality of piston chambers, as will be detailed more fully hereinafter.
  • the ram 32 is a pistonlike member that is slidably received within the confines of said outer housing section 58.
  • Said ram 32 comprises a lower section 62 of substantially solid cross section; an intermediate section 64 which is hollow or tubular in nature in that same includes a socket 65 which defines a bottom wall 66; and an upper portion 68.
  • the upper portion 68 is defined by an apertured plate member 63 secured to the uppermost end of the intermediate section 64 by one or more bolt members 71. Accordingly, when assembled as shown in FIG. 2, said apertured plate member 63 in effect provides an inwardly extending annular flange which includes an upper surface 69 and a lower surface 70.
  • the housing core section 60 is provided with an annular flangelike formation 72 on the innermost portion thereof.
  • Said flangelike portion 72 provides an upper surface 74 and a lower surface 76.
  • the core section 60 is slidably received within socket 65. Accordingly, with the elements disposed in this manner the bottom wall 66 of socket 65 provides a first piston surface that cooperates with the lowermost surface 76 on core 60 to define a first pistonlike chamber 82.
  • the upper surface 69 of said ram portion 68 provides a second piston surface which cooperates with the inner surface 80 of the outer housing section 58 to define a second piston chamber 84.
  • a third piston chamber 86 with the inner or lower surface 70 of said plate member 63 providing a third piston surface.
  • the housing arrangement 48 includes a plurality of fluid passages. More specifically, with regard to the first piston chamber 82, the core element 60 has a first passageway 90 formed therein which is adapted to be placed in communication with said source of fluid under pressure by means of the fittings and tubing, designated generally 91. Regarding the second chamber 84, the outer housing section 58 is provided with a passageway 96 which communicates therewith. In order to permit said passageway 96 to be jointed or coupled to a source of fluid under pressure the entrance to said passageway 96 is threaded and there is disposed therein an elbow 98 connectable with conduit means which lead to said source of fluid under pressure.
  • the fluid path for the third chamber 86 is provided by the passageway 100 formed in said core portion 60, said passageway also communicating with a source of fluid under pressure via the fittings and tubing 91, as illustrated atop of the housing arrangement 48.
  • various sealing means are provided, as illustrated in FIG. 2.
  • the ram 32 may be reciprocated by the application of fluid under pressure to said chambers. That is to say, if fluid under pressure is introduced into either or both chambers 82 or 84, the ram 32 will be moved downwardly in the direction indicated by the arrow 104. The force exerted during said movement depends upon the total surface area of the pistonlike surfaces upon which said fluid acts. More specifically, if fluid is introduced into both chambers 82 and 84, the entire area of said pistonlike surfaces 66 and 69 will be available, thus providing maximum force on the down stroke.
  • fluid under pressure is introduced into the third piston chamber 86.
  • said fluid will operate on the piston surface 70 to move the ram in the upward direction, this movement simultaneously forcing fluid out of the chambers 82 and 84.
  • FIGS. 3-7 A fluid control system or circuit for effecting the aforediscussed operation of the press 10 is illustrated schematically in FIGS. 3-7 in conjunction with a cross-sectional representation of the ram arrangement 33.
  • said control apparatus includes various valving elements which are illustrated schematically, and in the particular disposition or condition required to provide the fluid paths needed in effecting movement of the ram 32. Accordingly, said valving elements will be designated by like reference characters throughout FIGS. 3-7.
  • FIG. 3 the hydraulic ram arrangement 30 discussed previously is illustrated in section, with the fluid passages 92, 96 and 100 shown in association with said fluid control system, designated generally 110.
  • the system is essentially comprised of valving elements and fluid lines, and
  • valve 120 as illustrated includes fluid lines 112, 114 and 116 associated with the aforementioned passages 92, 96 and 100, respectively.
  • valve elements 120 and 122 each said valve element having four separate ports or passages associated with various fluid lines of system 110. Accordingly, by operation of said valve elements various distinct fluid paths may be attained, as will be detailed more fully.
  • these ports or passages are designated 123, 124, 125 and 126, for valve 120, and 123, 124, 125' and 126' for valve 122.
  • a source of fluid under constant pressure is provided and illustrated schematically at 130.
  • the fluid pressure source 130 is joined to the fluid circuit or system 110 by means of conduit 131 which is coupled to port 123 of valve 120.
  • a first reservoir or sump 132 which is joined to port 124 of fluid system 110 by a conduit or fluid line 133.
  • a second reservoir or sump 132' coupled with the port 124 of valve 122.
  • the reservoirs 132 and 132 may be one and the same, but they are illustrated individually for purposes of clarity and to facilitate understanding of the overall operation of the system.
  • valves 120 and 122 are linked together by the fluid line 136 which interconnects port 126 to the port 123' of valve 122.
  • the remaining valve ports 125, 125' and 126 are in communication with the previously discussed fluid lines 116, 114 and 112, respectively.
  • valves 120 and 122 are three position valves having an assemblage that includes an internal, movable member that upon movement thereof will intercon nect certain of the valve ports.
  • valve 120 is a solenoid operated valve, with the opposed solenoids 140 and 142 effecting movement of said internal member between two extremes or positions, said valve including a spring biasing arrangement, or its equivalent, to bias said internal member to the third or intermediate position as shown.
  • the valve 122 as illustrated, is a manually operated valve, the lever 144 effecting the desired positioning of the internal member of said valve.
  • various alternate or equivalent valving structures may be employed, as well as equivalent actuating means from those illustrated and described.
  • valve 120 same is adapted to effect three distinct arrangements or modes of interconnection between the fluid ports 124-126, which arrangements are illustrated in FIGS. 3, 4 and 5, respectively.
  • FIG. 3 With the internal member of said valve 120 in the neutral position, ports 123 and- 124 are interconnected such that the fluid under pressure transmitted from the source 130 will be discharged directly into reservoir or sump 132, with the ports 125 and 126 being blocked.
  • FIG. 4 the internal member of said valve being indexed to the right, the ports 123 and 126 are interconnected as are ports 124 and 125.
  • port 123 will now communicate with port 125 and port 124 is now interconnected with port 126.
  • valve arrangement 122 the situation or arrangement achieved when said valve is in the neutral or intermediate position is illustrated in either of FIGS. 3-5.
  • the port 123' is in effect an inlet port, as it is coupled to and receives fluid from port 1260f valve 120.
  • inlet port 123' is interconnected to ports 125' and 126, port 124 being blocked.
  • port 123 will communicate directly with port 125', while port 126 is associated with the reservoir or sump 132' by means of the port 124'.
  • port 123 will be coupled directly to port 126' and port 125' will be in association with the reservoir or sump 132' via port 124' and fluid line 133'. Accordingly, with the above discussion of the various valve positions in mind, there will be evolved hereinafter a detailed description of the operation of the shear press apparatus of the present invention.
  • valve 120 and 122 With the valve elements 120 and 122 in the position illustrated in FIG. 3, the fluid under pressure provided by the source 130 will enter valve 120 by means of the port 123 and,
  • valve 120 due to the connection of port 123 with port 124, will be discharged into the reservoir or sump 132.
  • the fluid entering valve 120 through port 123 will be transported by line 136 to valve 122, and discharged therefrom, via ports I23, and 126, into lines 114 and 112, thus introducing fluid under pressure into the first and second piston chambers 82 and 84.
  • the ram 32 Upon introduction of fluid into said chambers the ram 32 will move downward in the direction'indicated by arrow 104.
  • this movement of the ram 32 will be effective to reduce the volume in chamber 86, thus forcing any fluid therein out through lines 100, 116 and through the ports 125 and 124 of valve 120, into sump 132.
  • the valve position as illustrated in FIG. 4, it should be kept in mind that the total surface area of both piston surfaces 66 and 69 will be subjected to fluid under pressure and accordingly the ram 32 will move downward with maximum force.
  • valve 122 is maintained in the position illustrated in FIG. 5, wherein ports 124 and 126 are interconnected, as are ports 123 and 125. Valve 122 remains in the intermediate position.
  • the fluid from source 130 will enter linel16 via the ports 123 and 125, and in turn will be introduced into the third piston chamber 86.
  • the force exerted by said fluid will act upon the third piston surface 70 to move the ram arrangement 32 upwardly, as indicated by the arrow 105.
  • valve 122 is constructed so that operation thereof to either of the positions illustrated in FIGS. 6 or 7 will achieve a selective application of fluid under pressure to one or the other of said first and second chambers.
  • valve 122 By the movement of the valve 122 between either one of the three positions a variation in the force exerted by the ram arrangement 32 during its downward stroke may be obtained.
  • introduction of fluid under pressure into the third piston chamber 86 in order to effect the return stroke may be achieved by movement of the valve 120 to the position illustrated in FIG. 5.
  • the present invention provides a press unit which enables the metal fabricator to select an operating force commensurate with the job at hand.
  • a variable force hydraulic press comprising: a housing; a pistonlike ram element slidably positioned within said housing, said ram element having first and second piston surfaces facing in the same direction and cooperating with sald housing to define corresponding first and second piston chambers; conduit means providing a fluid path whereby each said chamber may be operably connected.
  • control means associated with said conduit means for selectively applying fluid pressure to either or both said chambers, said control means comprising a pair of valve elements, the first said valve element receiving fluid under pressure from a source and adapted for transmittal of said fluid to the second valve element, said second valve element being a three position valve such that when in a first position a fluid path to both said chambers will be provided, while when in either of the two remaining positions the fluid path thus established will be but to one or the other of said chambers, such that the ram element may be moved in one direction with the force exerted thereon varying according to the surface or surfaces to which fluid under pressure is applied.
  • said core element includes a flange portion on the inner end thereof having a diameter greater than the diameter of said core portion surrounded by the inner periphery of said flange portion on the ram, and the lower surface of said ram flange portion providing a third piston surface, said third piston piston surface cooperating with the upper surface of said core flange portion to define the third piston chamber, and conduit means providing a fluid path from said third chamber to the exterior of said housing whereby said chamber may be placed in operable association with said source of fluid under pressure to move the ram in a direction opposite to said one direction.
  • a variable force hydraulic'press as defined in claim I wherein said pistonlike ram element'includes a third piston surface facing in a direction opposite'to said first and second surface, said third piston surface cooperating with the housing to define a third piston chamber, and said conduit means further defining a fluid path whereby said third chamber may be operably associated with said source of fluid under pressure to move said ram element in a direction opposite tosaid one direction.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Control Of Presses (AREA)
  • Bending Of Plates, Rods, And Pipes (AREA)
  • Press Drives And Press Lines (AREA)
US799309A 1969-02-14 1969-02-14 Variable force hydraulic press Expired - Lifetime US3563136A (en)

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US79930969A 1969-02-14 1969-02-14

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US (1) US3563136A (enrdf_load_stackoverflow)
DE (1) DE2006529A1 (enrdf_load_stackoverflow)
FR (1) FR2035432A5 (enrdf_load_stackoverflow)
GB (1) GB1293462A (enrdf_load_stackoverflow)

Cited By (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3019947A1 (de) * 1980-05-24 1981-12-03 Fried. Krupp Gmbh, 4300 Essen Walzenanstellvorrichtung
US4316597A (en) * 1980-01-24 1982-02-23 United Technologies Corporation Compact valve actuator
US4823658A (en) * 1985-10-18 1989-04-25 Spicer Andrew I Punch presses
US4925618A (en) * 1987-02-28 1990-05-15 Nissei Jushi Kogyo Kabushiki Kaisha Mold clamping method
US5299489A (en) * 1991-05-17 1994-04-05 Reo Hydraulic Pierce & Form Pressure cylinder with low tolerance fit capable of supporting large transverse loads
US5865089A (en) * 1997-09-19 1999-02-02 Langer; John W. Linear thruster
US5957029A (en) * 1997-09-19 1999-09-28 Bimba Manufacturing Co. Linear thruster
RU2191698C2 (ru) * 2000-12-08 2002-10-27 Сибирский государственный индустриальный университет Преобразователь давления гидропресса
US20050098326A1 (en) * 2003-10-28 2005-05-12 Masahiro Tosen Hydraulic circuit for hydraulic cylinder
US20070048116A1 (en) * 2005-07-18 2007-03-01 Thomas Friedrich Lifting/pivoting apparatus for loading board walls and/or loading ramps
US8601934B1 (en) * 2012-08-06 2013-12-10 Westendorf Manufacturing Co., Inc. Two piston cylinder
CN107649680A (zh) * 2017-09-18 2018-02-02 南京东部精密机械有限公司 数控机电液混合驱动伺服粉末成形机泵控上冲功能集合系统
IT201900012969A1 (it) * 2019-07-26 2021-01-26 Mecolpress S P A Apparecchiatura per lo stampaggio di materiali.

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4242901A (en) * 1978-03-20 1981-01-06 Canron Corp. Hydraulic press with integral knockout and stroke control
JPS54154486U (enrdf_load_stackoverflow) * 1978-04-20 1979-10-26
NL8301541A (nl) * 1983-05-02 1984-12-03 Fontijne Bv Machine Hydraulische pers voor het compacteren van drums met radio-actief afval.
US4968860A (en) * 1988-05-19 1990-11-06 Omron Tateisi Electronics Co. Light emitting type push button switch

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1552768A (en) * 1922-10-31 1925-09-08 Eric M Smith Hydraulic press apparatus
US2502547A (en) * 1948-05-11 1950-04-04 Denison Eng Co Hydraulic apparatus
US2519900A (en) * 1948-12-10 1950-08-22 Hpm Dev Corp Control circuit for multiple hydraulic press systems
US2602294A (en) * 1950-12-21 1952-07-08 American Steel Foundries Hydraulic and electrical system for operating presses
US2805447A (en) * 1953-11-05 1957-09-10 Voges Fred William Safety circuit for molding machine
US3170379A (en) * 1962-02-13 1965-02-23 Dempster Brothers Inc Hydraulic system

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1552768A (en) * 1922-10-31 1925-09-08 Eric M Smith Hydraulic press apparatus
US2502547A (en) * 1948-05-11 1950-04-04 Denison Eng Co Hydraulic apparatus
US2519900A (en) * 1948-12-10 1950-08-22 Hpm Dev Corp Control circuit for multiple hydraulic press systems
US2602294A (en) * 1950-12-21 1952-07-08 American Steel Foundries Hydraulic and electrical system for operating presses
US2805447A (en) * 1953-11-05 1957-09-10 Voges Fred William Safety circuit for molding machine
US3170379A (en) * 1962-02-13 1965-02-23 Dempster Brothers Inc Hydraulic system

Cited By (18)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4316597A (en) * 1980-01-24 1982-02-23 United Technologies Corporation Compact valve actuator
DE3019947A1 (de) * 1980-05-24 1981-12-03 Fried. Krupp Gmbh, 4300 Essen Walzenanstellvorrichtung
US4429618A (en) 1980-05-24 1984-02-07 Fried. Krupp Gesellschaft Mit Beschrankter Haftung Hydraulic roll-adjustment apparatus
US4823658A (en) * 1985-10-18 1989-04-25 Spicer Andrew I Punch presses
US4925618A (en) * 1987-02-28 1990-05-15 Nissei Jushi Kogyo Kabushiki Kaisha Mold clamping method
US5299489A (en) * 1991-05-17 1994-04-05 Reo Hydraulic Pierce & Form Pressure cylinder with low tolerance fit capable of supporting large transverse loads
US5865089A (en) * 1997-09-19 1999-02-02 Langer; John W. Linear thruster
US5957029A (en) * 1997-09-19 1999-09-28 Bimba Manufacturing Co. Linear thruster
RU2191698C2 (ru) * 2000-12-08 2002-10-27 Сибирский государственный индустриальный университет Преобразователь давления гидропресса
US20050098326A1 (en) * 2003-10-28 2005-05-12 Masahiro Tosen Hydraulic circuit for hydraulic cylinder
US7047734B2 (en) * 2003-10-28 2006-05-23 Komatsu Ltd. Hydraulic circuit for hydraulic cylinder
CN100351528C (zh) * 2003-10-28 2007-11-28 株式会社小松制作所 使用油压缸的油压回路
US20070048116A1 (en) * 2005-07-18 2007-03-01 Thomas Friedrich Lifting/pivoting apparatus for loading board walls and/or loading ramps
US8601934B1 (en) * 2012-08-06 2013-12-10 Westendorf Manufacturing Co., Inc. Two piston cylinder
US8875615B1 (en) * 2012-08-06 2014-11-04 Westendorf Manufacturing Co., Inc. Two piston cylinder
CN107649680A (zh) * 2017-09-18 2018-02-02 南京东部精密机械有限公司 数控机电液混合驱动伺服粉末成形机泵控上冲功能集合系统
IT201900012969A1 (it) * 2019-07-26 2021-01-26 Mecolpress S P A Apparecchiatura per lo stampaggio di materiali.
EP3769949A1 (en) * 2019-07-26 2021-01-27 Mecolpress S.p.A. Apparatus for moulding materials

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Publication number Publication date
GB1293462A (en) 1972-10-18
FR2035432A5 (enrdf_load_stackoverflow) 1970-12-18
DE2006529A1 (de) 1970-09-03

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