[go: up one dir, main page]

WO2008123009A1 - Dispositif d'étanchéité pour système d'injection de machines de moulage sous pression - Google Patents

Dispositif d'étanchéité pour système d'injection de machines de moulage sous pression Download PDF

Info

Publication number
WO2008123009A1
WO2008123009A1 PCT/IT2008/000228 IT2008000228W WO2008123009A1 WO 2008123009 A1 WO2008123009 A1 WO 2008123009A1 IT 2008000228 W IT2008000228 W IT 2008000228W WO 2008123009 A1 WO2008123009 A1 WO 2008123009A1
Authority
WO
WIPO (PCT)
Prior art keywords
sealing elements
injector piston
injection system
battery
head
Prior art date
Application number
PCT/IT2008/000228
Other languages
English (en)
Inventor
Flavio Mancini
Federico Albertini
Original Assignee
Italpresse Industrie S.P.A.
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Italpresse Industrie S.P.A. filed Critical Italpresse Industrie S.P.A.
Publication of WO2008123009A1 publication Critical patent/WO2008123009A1/fr

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
    • B22D17/00—Pressure die casting or injection die casting, i.e. casting in which the metal is forced into a mould under high pressure
    • B22D17/02—Hot chamber machines, i.e. with heated press chamber in which metal is melted
    • B22D17/04—Plunger machines
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
    • B22D17/00—Pressure die casting or injection die casting, i.e. casting in which the metal is forced into a mould under high pressure
    • B22D17/20—Accessories: Details
    • B22D17/2015—Means for forcing the molten metal into the die
    • B22D17/203—Injection pistons

Definitions

  • This invention concerns an injection system for die-casting machines for molten or semi-molten metal alloys, in particular but not exclusively indicated for hot chamber systems, and in particular an injection system provided with non metallic dynamic sealing elements that yield under compression.
  • the liner and some dynamic seal elements placed between them are at present using materials resistant to high temperatures, able to support the corrosive action of the alloys in the molten or semi-liquid state, to resist wear generated by the sliding of the components in relative motion and to prevent or impede possible gripping, plus restrain the alloy leaks so as to achieve an acceptable, economic duration of such components.
  • dynamic sealing elements in the form of metal split rings applied coaxially to the injection piston are generally used.
  • the split rings are interrupted in the circumferential direction which enables them to compress and expand elastically in a radial direction and are mounted coaxially to the injector piston in special grooves or circumferential housings provided in its lateral surface.
  • the split rings are compressed in their housings tightening onto the injector piston and successively they expand due to their flexibility coming into contact with the internal surface of the cylinder.
  • the pressure generated by the sealing elements on the walls of the liner sets the sealing level at the injection pressure of the alloy being worked.
  • one or more sealing split rings can be provided.
  • the patent JP 55088966 describes a method for avoiding erosion and damaging of the cylinder of a die-casting machine on the part of the molten metal by making the internal surface of the liner and the sealing ring on the injector piston with two different types of ceramic material.
  • Patent US 4899804 describes a head of an injector piston for die casting comprising a wear and seal ring the external diameter of which corresponds to the diameter of the liner.
  • the injector piston comprises a cap that is used to hold the annular sealing element on the injector piston.
  • the material of the annular sealing must be harder and thermally less conductive than the material of the head of the injector piston.
  • the pressure of the alloy is very low in the initial phase of the injector piston stroke that is when the alloy reaches at a low speed the gate in the metal die.
  • the pressure quickly increases to allow filling of the die at a high speed and, in the third phase of the die casting process, the pressure becomes very high to enable the casting to be compact. Consequently, by varying the radial pressure that the sealing elements exert on the internal surface of the liner to avoid leaking of the alloy due to the pressure of the die casting cycle, it is possible to reduce the radial stresses, and consequently the wear, on the sealing elements and on the liner, with greater benefits for the duration of such components.
  • the patent US 5350007 describes an injection system for die-casting machines that comprises an injector piston in which some circumferential grooves connected to the pressurization surfaces by means of a conduit passage system are provided.
  • the grooves house some semirings with play which are solicited radially towards the exterior by the pressure of the molten metal which, during the injection phase, returns through the passage conduits provided in the injector piston.
  • the rings must meet certain geometrical requirements that depend on the materials used (Young's modulus), on the internal diameter of the cylinder and on the injection pressure of the metal.
  • the objective of this invention therefore is to supply an injection system for die-casting systems that enables minimizing of wear between the sealing elements and the liner. Said objective is achieved with an injection system whose main characteristics are specified in the first claim, whereas other characteristics are specified in the other claims.
  • the injection system according to this invention is provided with dynamic sealing elements made of a non metal graphite base material yielding under compression, such dynamic sealing elements being compressed in an axial direction by means of axial compression positioned on the head of the injector piston.
  • the compression in an axial direction causes, due to the compliance of the material, an expansion of the dynamic sealing elements in a radial direction against the internal surface of the liner, necessary to restrain the alloy being worked from leaking.
  • the degree of compression exerted by the axial compression means is proportional to the injection pressure during the die-casting cycle, starting from a static pre-load condition necessary to guarantee sealing under minimum pressure conditions.
  • a first important advantage of the injection system according to this invention is that the choice of graphite as a base material for the construction of the dynamic sealing elements enables good sliding characteristics to be achieved between the components in relative motion minimizing the wear problems due to sliding.
  • the proportionality between the degree of compression exerted by the means of compression on the sealing elements and the die- casting cycle pressure generates variable radial pressures on the internal surface of the cylinder, resulting in the fundamental advantage of a further reduction of the wear between the elements in relative motion.
  • Yet another advantage of the injection system according to this invention is that the compression means that act on the dynamic sealing elements can easily be manually and/or automatically adjusted, allowing the regular control of the static preloading necessary to guarantee sealing under minimum pressure conditions.
  • the dynamic compression action exerted by the means of compression during the several phases of the die-casting cycle which can in certain cases be achieved, can be fully automated allowing the further advantage of an authentic optimization of the sealing level of the most important parameters of the die-casting cycle.
  • figure 1 shows a longitudinal section view of a first possible form of an injection system for die-casting machines according to this invention
  • figure 2 shows a longitudinal section view of a second possible form of an injection system for die-casting machines according to this invention
  • figure 3 shows a longitudinal section view of the injection system for die-casting machines in figure 2, to which has been added some manual adjustment elements of the static preloading required by the sealing elements
  • figure 4 shows a longitudinal section view of the injection system for die-casting machines in figure 3, in which the adjustment elements of the static preloading required by the sealing elements are operated by a rotary servomotor
  • figure 5 shows a longitudinal section view of a third possible form of an injection system for die-casting machines according to this invention, in which the dynamic compression of the sealing elements during the several die-casting phases of the cycle is automatically adjusted in relation to the
  • the injection system for die-casting machines comprises as is well known, a liner 1 for a molten or semi-liquid metallic alloy and an injector piston 2 inserted coaxially in the liner 1 and connected to an actuator 2a so as to impart the injector piston 2 with an alternative motion.
  • the liner 1 is provided with an input port 3 and a delivery port 4 that is connected to a mould M by means of a pouring channel C.
  • the injector piston 2 is provided with one or more dynamic sealing elements 5 basically annular shaped to come into contact with the internal surface of the liner 1 to prevent the alloy from leaking and consequent drop in pressure during all the die-casting process phases.
  • the sealing elements 5 are positioned stacked on the injector piston head 2 and are made of a non metallic material with a graphite base and which yields under pressure. This choice is based on the fact that graphite based materials have already been used with success for the construction of static sealing elements such as, for example, those used in valves for the petrochemical industry.
  • the sealing elements 5 are made of foamed graphite, a material which is extremely heat resistant and well suited to the realisation of sealing elements for high temperature applications.
  • the sealing elements 5 can in addition be provided internally and/or externally with elements resistant to the molten alloy and to temperatures from 600 to 800 0 C, both the non metallic type, such as, for example, carbon fibre, and the metallic type as long as they can resist attacks from the molten alloy being worked, and they can also comprise spring equipped elements so as to allow the gathering and release of elastic force, for example of the conical disk springs.
  • the shape of the transversal section is of great importance for the good operation of the sealing elements 5.
  • the sealing elements 5 have a quadrangular shaped ruling transversal section, with ratios between the sides of between one and two and internal angles of between 60° and 120°.
  • the injection system according to this invention comprises axial means of compression so as to compress the sealing elements 5 in an axial direction to increase the radial pressure that the latter exert on the internal surface of the liner 1.
  • axial means of compression so as to compress the sealing elements 5 in an axial direction to increase the radial pressure that the latter exert on the internal surface of the liner 1.
  • the axial means of compression are positioned on the head 6 of the injector piston 2 and generally comprise a plate 7 positioned on the free end of the battery of sealing elements 5 and a screw register 8 axially attached to the injector piston 2.
  • the plate 7 has an annular shape and is inserted to slide on a cylindrical pin 6a positioned on an axis with the injector piston 2 on its head 6.
  • the cylindrical pin 6a centres the battery of sealing elements 5 with respect to the injector piston 2 and is provided with a threaded end 6b.
  • the screw register 8 is a locknut that engages with the threaded end 6b of the cylindrical pin 6a causing pressure of the plate 7 on the sealing elements 5.
  • the compression in an axial direction determines a radial pressure of the sealing elements 5 on the internal surface of the liner 1.
  • the axial compression means are also suitable to dynamically compress the sealing elements 5 in a mode directly proportional to the injection pressure.
  • the plate 7 is solicited in the axial direction directly by the molten alloy which is in the injection pressure p, schematized in the figure by means of the dotted arrows.
  • the pressure p exceeds the static preload p0 setting for the sealing elements 5, the plate 7, that is free to move axially, increases compression on the sealing elements 5, causing greater radial pressure of the same on the internal surface of the liner 1.
  • the sealing of the system is dynamically adapted to the instantaneous pressure of the alloy being worked, enabling a reduction in contact pressure each time the instantaneous pressure drops so as to achieve less wear of the components and in particular of the internal surfaces of the liner 1.
  • the plate 7 is provided with a hollow stem 7a with internal threading which is inserted coaxially in the injector piston 2, in an axial cavity 2b provided in its head 6, and axially centres the battery of sealing elements 5 with respect to it.
  • the screw register 8 is a tie rod provided with a head 8a and a threaded end 8b and lodged in the injector piston 2 in an axial seat 2c provided at the opposite end to its head 6.
  • the threaded end 8b of the tie rod engages with the hollow threaded stem 7a of the plate 7, causing in this way the compression of the sealing elements 5 between the plate 7 and the head 6.
  • the static preload pO necessary to guarantee the seal in minimum pressure conditions is achieved by adequately tightening the screw register
  • the screw register 8 in the hollow stem 7a of the plate 7.
  • the screw register 8 comprises in addition a number of springs, for example some Belleville washers, positioned between its head 8a and the axial seat 2c.
  • the springs for example some Belleville washers, positioned between its head 8a and the axial seat 2c.
  • the springs 9 stress the screw register 8 in an axial direction maintaining the static preload p0 set during assembly on the battery of sealing elements 5, constant.
  • the springs 9 are made of a material able to support temperatures of about 600 0 C.
  • a torsion constraint can be provided, such as for example a key 10 or a grooved joint, positioned between the hollow stem 7a and the axial cavity 2b provided in the head 6 of the injector piston 2.
  • Figure 3 shows the possible form exemplified in figure 2, in which the axial seat 2c of the screw register 8 has a diametral through opening 2d that houses a transverse element 11.
  • the transverse element 11 supports the head 8a of the screw register 8 and, if present, the springs 9.
  • the ends of the transverse element 11 project out of the injector piston 2 and are in contact with a ring nut 12 positioned coaxially to the injector piston 2, between the transverse element 11 and the head 6, and turning on a threaded portion 2e provided on the injector piston 2 near the through diametral opening 2d.
  • the ring nut 12 is operated in rotation by means of a servomotor 13 and a clutch 14, for example a friction clutch or claw clutch, positioned coaxially to the actuator 2a.
  • a clutch 14 for example a friction clutch or claw clutch, positioned coaxially to the actuator 2a.
  • Figure 5 shows a third possible form of the injection system according to this invention, in which the axial seat 2c of the injector piston 2 is hermetically sealed and the head 8a of the screw register 8 forms a lower chamber 15 and an upper chamber 16 provided respectively with a first hydraulic conduit 17 and a second hydraulic conduit 18 suitable for supplying a fluid under pressure to them such as, for example, hydraulic oil.
  • the screw register 8 acts therefore as a hydraulic plunger allowing continuous adjustment of the static preload p0 and the dynamic compression of the battery of sealing elements 5 during all the die-casting phases.
  • the continuous adjustment can be carried out in the automatic mode, for example, by connecting the first and second 17, 18 hydraulic conduits respectively to two pressurization chambers 2a', 2a" of the actuator 2a.
  • the first hydraulic conduit 17 is connected to a first pressurization chamber 2a' that sets the injection stroke of the injector piston 2
  • the second hydraulic conduit 18 is connected to a second pressurization chamber 2a" that sets the return stroke of the injector piston 2 after the injection of the molten alloy.
  • the battery of sealing elements 5 will be compressed and decompressed in ratio with the pressure present in the actuator 2a.
  • the hydraulic conduits 17, 18 can be fed separately by means of a pump 19 and connected to a hydraulic servomechanism 20, for example a proportional group, and said elements 19, 20 can be advantageously controlled in an active mode by a control unit CU to carry out the adjustment of the static preload p0 and the dynamic compression of the sealing elements 5 depending on the fundamental parameters of the die-casting cycle, such as strokes, pressures, times and speeds.
  • a control unit CU to carry out the adjustment of the static preload p0 and the dynamic compression of the sealing elements 5 depending on the fundamental parameters of the die-casting cycle, such as strokes, pressures, times and speeds.
  • These parameters can be obtained from the ideal operating tables memorised in the control unit CU, or can be detected at any moment by appropriate sensors (not shown) connected to the control unit CU.
  • Figure 7 shows a fourth possible form of the injection system for die- casting machines according to this invention, in which the plate 7 has an annular shape and a stopper element 21 is inserted coaxially in the battery of sealing elements 5.
  • the head 21a of the stopper element 21 is lodged on plate 7 and its stem 21 b is threaded and screwed in a slot 6c provided in the head 6 of the injector piston 2.
  • the screw register 8 is a threaded ring nut positioned in a turning mode on the threaded end 2f of the injector piston 2 screwed to the actuator 2a.
  • a screw down element 22 is placed coaxially to the injector piston 2 between the threaded ring nut and the battery of sealing elements 5.
  • FIG. 8 shows a fifth possible form of the injection system according to this invention. Analogous to the possible form illustrated in figure 7, the plate 7 has an annular shape and a stopper element 21 is inserted coaxially into the battery of sealing elements 5.
  • the head 21a of the stopper element 21 is lodged on the plate 7 and its stem 21 b is threaded and screwed into a slot 6c provided in the head 6 of the injector piston 2.
  • the register 8 is a transverse element placed in a through diametral opening 2g provided in the injector piston 2 and connected at the top to the threaded stem 24 of a servomotor 25 coaxial to the actuator 2a.
  • a screw down element 22 is placed between the transverse element and the battery of sealing elements 5.
  • the drive of the servomotor 25 causes a variation of the pressure of the screw down element 22 on the battery of sealing elements 5 to allow the continuous adjustment of the static preload p0 of the dynamic compression of the battery of sealing elements 5.
  • annular pressure element 23 is preferably positioned which has a transversal section basically coincident with that of the sealing elements 5.
  • the sealing elements 5 can have a generatrix section which is not quadrangular but for example trapezoidal, to vary the rigidity characteristics, resistance to wear and sealing of the battery pressure, and it is also possible to combine together sealing elements with different generatrix section shapes.
  • control algorithms based, other than on the fundamental parameters of the system, also on the time constants characteristic of the die-casting cycle, being able in this way to adjust the compression of the sealing elements with greater precision and in advance with respect to the individual phases of the production process.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Fuel-Injection Apparatus (AREA)

Abstract

Un système d'injection de machines de moulage sous pression comprend un revêtement (1) destiné à une alliage métallique fondu ou semi-liquide et un piston injecteur (2) introduit coaxialement dans ledit revêtement (1) et relié à un actionneur (2a) qui lui imprime un mouvement alternatif. Le revêtement (1) possède des ports d'amenée et d'induction (3, 4) de l'alliage fondu et ledit piston injecteur (2) possède au moins un élément d'étanchéité dynamique de forme annulaire pouvant être mise en contact avec la surface intérieure du revêtement (1) pour empêcher la fuite de l'alliage et des baisses conséquentes de pression pendant toutes les phases du moulage sous pression. Les éléments d'étanchéité (5) sont empilés sur le sommet (6) du piston injecteur (2) et sont réalisés dans un matériau non métallique à base de graphite cédant lorsqu'on le comprime. Le piston injecteur (2) comprend des moyens de compression axiaux (7, 8) des éléments d'étanchéité (5) placés à hauteur de la tête (6) du piston injecteur (2) et comprenant une plaque (7) logée sur l'extrémité libre de l'ensemble des éléments d'étanchéité (5) et un élément indicateur à vis (8) connecté axialement au piston d'injecteur (2) de manière à comprimer ladite plaque (7) contre la batterie des éléments d'étanchéité (5) pour établir une précharge statique dans ces éléments (pϑ), ce qui est nécessaire pour garantir l'étanchéité en conditions de pression minimales. La plaque (7) est, de plus, mobile axialement de manière à comprimer davantage l'ensemble des éléments d'étanchéité (5) dans un sens axial proportionnellement à la pression d'injection instantanée de l'alliage fondu.
PCT/IT2008/000228 2007-04-05 2008-04-07 Dispositif d'étanchéité pour système d'injection de machines de moulage sous pression WO2008123009A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
ITML2007A000708 2007-04-05
ITML20070708 2007-04-05

Publications (1)

Publication Number Publication Date
WO2008123009A1 true WO2008123009A1 (fr) 2008-10-16

Family

ID=39590884

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/IT2008/000228 WO2008123009A1 (fr) 2007-04-05 2008-04-07 Dispositif d'étanchéité pour système d'injection de machines de moulage sous pression

Country Status (1)

Country Link
WO (1) WO2008123009A1 (fr)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2013179177A2 (fr) 2012-05-29 2013-12-05 Flavio Mancini Pompe d'injection pour le coulage en chambre chaude d'alliages légers corrosifs
WO2015076748A1 (fr) 2013-11-25 2015-05-28 Pratt & Whitney Services Pte Ltd. Segment de piston remplaçable pour piston de machine à couler sous pression
CN113505481A (zh) * 2021-07-08 2021-10-15 东软睿驰汽车技术（沈阳）有限公司 壳体密封失效压力的确定方法、装置和电子设备

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR908322A (fr) * 1944-12-20 1946-04-05 Dispositif de moulage sous pression
US3092880A (en) * 1959-08-25 1963-06-11 Glen R Morton Die casting machine plunger tip
US4899804A (en) * 1989-02-21 1990-02-13 Hammerer Norman L Plunger tip for cold chamber die cast machine
US5350007A (en) * 1992-01-30 1994-09-27 Nippon Light Metal Co., Ltd. Injection apparatus for a hot-chamber die-cast machine
JPH0994648A (ja) * 1995-09-28 1997-04-08 Kobe Steel Ltd プランジャーチップ
DE20309181U1 (de) * 2003-06-13 2004-10-28 Allper Ag Mehrteiliger Kolben für eine Kaltkammer-Druckgießmaschine
JP2005329431A (ja) * 2004-05-20 2005-12-02 Kubota Corp ダイカストマシン用プランジャーチップ
US20050284602A1 (en) * 2004-06-25 2005-12-29 Kubota Corporation Plunger tip for die casting machines

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR908322A (fr) * 1944-12-20 1946-04-05 Dispositif de moulage sous pression
US3092880A (en) * 1959-08-25 1963-06-11 Glen R Morton Die casting machine plunger tip
US4899804A (en) * 1989-02-21 1990-02-13 Hammerer Norman L Plunger tip for cold chamber die cast machine
US5350007A (en) * 1992-01-30 1994-09-27 Nippon Light Metal Co., Ltd. Injection apparatus for a hot-chamber die-cast machine
JPH0994648A (ja) * 1995-09-28 1997-04-08 Kobe Steel Ltd プランジャーチップ
DE20309181U1 (de) * 2003-06-13 2004-10-28 Allper Ag Mehrteiliger Kolben für eine Kaltkammer-Druckgießmaschine
JP2005329431A (ja) * 2004-05-20 2005-12-02 Kubota Corp ダイカストマシン用プランジャーチップ
US20050284602A1 (en) * 2004-06-25 2005-12-29 Kubota Corporation Plunger tip for die casting machines

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2013179177A2 (fr) 2012-05-29 2013-12-05 Flavio Mancini Pompe d'injection pour le coulage en chambre chaude d'alliages légers corrosifs
CN104334299A (zh) * 2012-05-29 2015-02-04 F·曼奇尼 用于腐蚀性轻合金的热室压铸的喷射泵
US9126261B2 (en) 2012-05-29 2015-09-08 Flavio Mancini Injection pump for the hot-chamber die casting of corrosive light alloys
WO2015076748A1 (fr) 2013-11-25 2015-05-28 Pratt & Whitney Services Pte Ltd. Segment de piston remplaçable pour piston de machine à couler sous pression
EP3074158A4 (fr) * 2013-11-25 2016-12-21 Pratt & Whitney Services Pte Ltd Segment de piston remplaçable pour piston de machine à couler sous pression
US9962761B2 (en) 2013-11-25 2018-05-08 Pratt & Whitney Services Pte Ltd. Replaceable piston ring for die casting machine plunger
CN113505481A (zh) * 2021-07-08 2021-10-15 东软睿驰汽车技术（沈阳）有限公司 壳体密封失效压力的确定方法、装置和电子设备
CN113505481B (zh) * 2021-07-08 2023-08-01 东软睿驰汽车技术（沈阳）有限公司 壳体密封失效压力的确定方法、装置和电子设备

Similar Documents

Publication Publication Date Title
RU2510475C1 (ru) Запорный клапан с невыдвижным шпинделем
JP4175473B2 (ja) 研摩材流加工装置及び方法
WO2008123009A1 (fr) Dispositif d'étanchéité pour système d'injection de machines de moulage sous pression
US6490904B1 (en) Double action bottom former for high cyclic operation
US5195572A (en) Two part shot sleeve for die casting
CN109201832B (zh) 一种短模旋压成形装置
EP2855049B1 (fr) Pompe d'injection pour le coulage en chambre chaude d'alliages légers corrosifs
WO1990002017A1 (fr) Procede de fabrication de chambres pour soupape, etc.
EP0338036A1 (fr) Entrainement lineaire a assistance hydraulique
CS198165B2 (en) Liquid processing regulator
WO1998058198A1 (fr) Appareil de compression de garniture de vanne et son procede d'utilisation
CN114165402A (zh) 一种柱塞泵恒功率控制装置及方法
EP2391830B1 (fr) Actionneur de piston ajustable
JPS6051928B2 (ja) 冷間成形装置
CN105972224B (zh) 一种用于压铸机的新型电调阀
US20150219276A1 (en) Mono-material Divider Block Assembly
EP2470316B1 (fr) Ressort pneumatique pour dispositif de fermeture coulissant refractraire
RU2061792C1 (ru) Устройство для фрикционно-механического нанесения покрытий
US9962761B2 (en) Replaceable piston ring for die casting machine plunger
CN115916517B (zh) 径向压力机
WO2023125555A1 (fr) Dispositif de micro-réglage de système hydraulique et système d'étalonnage de réservoir le comprenant
RU2056183C1 (ru) Устройство для автоматического регулирования кинематического коэффициента при прессовании
CN202768968U (zh) 具有磨损补偿的超高压自动卸压装置
CN212928362U (zh) 一种联轴器
CA2557756A1 (fr) Verin hydraulique

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 08751541

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 08751541

Country of ref document: EP

Kind code of ref document: A1