EP0530244A1 - Injection unit for a hydraulic die-casting machine, provided with a device for the elimination of pressure peaks at injection. - Google Patents
Injection unit for a hydraulic die-casting machine, provided with a device for the elimination of pressure peaks at injection.Info
- Publication number
- EP0530244A1 EP0530244A1 EP91909466A EP91909466A EP0530244A1 EP 0530244 A1 EP0530244 A1 EP 0530244A1 EP 91909466 A EP91909466 A EP 91909466A EP 91909466 A EP91909466 A EP 91909466A EP 0530244 A1 EP0530244 A1 EP 0530244A1
- Authority
- EP
- European Patent Office
- Prior art keywords
- piston
- injection
- accumulator
- cylinder
- auxiliary
- Prior art date
- Legal status (The legal status 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 status listed.)
- Granted
Links
- 238000002347 injection Methods 0.000 title claims abstract description 76
- 239000007924 injection Substances 0.000 title claims abstract description 76
- 238000004512 die casting Methods 0.000 title claims description 5
- 230000008030 elimination Effects 0.000 title description 4
- 238000003379 elimination reaction Methods 0.000 title description 4
- 239000012530 fluid Substances 0.000 claims abstract description 27
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 8
- 239000002184 metal Substances 0.000 description 5
- 229910052757 nitrogen Inorganic materials 0.000 description 4
- 238000005266 casting Methods 0.000 description 3
- 238000007599 discharging Methods 0.000 description 2
- 206010010904 Convulsion Diseases 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000002093 peripheral effect Effects 0.000 description 1
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
- B22D17/20—Accessories: Details
- B22D17/2015—Means for forcing the molten metal into the die
Definitions
- injection unit for a hydraulic die-casting machine provided with a device for the elimination of pressure peaks at injection.
- the present invention relates to an injection unit for a hydraulic die-casting machine, provided with a device for the elimination of pressure peaks at injection.
- such injection units comprise an injection cylinder, an inject.on piston slidably housed in the cylinder and valve means suitable for sequentially placing in communication with the cylinder first a fluid supply pump for a possible slow advancement stage of the injection piston and subsequently a fluid accumulator for a second fast advancement stage of the injection piston.
- Such units also comprise a pressure multiplier which has the function of subsequently raising the pressure of the fluid acting on the injection piston for a third short advancement stage at slow speed and high pressure. The latter stage allows the molten metal to reach and fill with adequate compactness the most distant and difficult interstices of the casting cavity.
- the object of the present invention is to overcome this drawback by accomplishing an injection unit in which such pressure peak is eliminated.
- an injection unit for a hydraulic die-casting machine comprising an injection cylinder, a hydraulically-operated injection piston, a fluid accumulator for the operation at high speed of the injection piston during the injection stroke and a pressure multiplier for the operation at low speed and high pressure of the piston at the end of the injection stroke of the piston, characterized in that it further comprises an auxiliary cylinder/piston unit interposed between the injection piston and the accumulator to allow the advancement of the auxiliary piston under the action of the accumulator and the advancement of said injection piston in accordance with that of said auxiliary piston, the cross-section of said auxiliary cylinder being larger than the cross-section of said injection cylinder.
- the difference between the cross-sections of the injection piston and of the auxiliary piston is such that the auxiliary piston moves at a speed that is lower than that of the injection piston and reaches the end of the stroke in a controlled manner so as to avoid the creation of pressure peaks on the injected metal.
- Fig. 1 illustrates the unit at rest in one embodiment
- Fig. 2 illustrates the unit during the injection stage
- Fig. 3 illustrates the unit during the pressure multiplication stage
- Fig. 4 illustrates the unit during the return stage from the injection;
- Fig.s 5 - 8 illustrate another embodiment according to the invention in the same operating stages of Fig.s 1 - 4.
- the injection unit comprises a high-speed accumulator 1 consisting of a cylindrical chamber 14 in which a piston 15 slides.
- the upper part of the cylindrical chamber 14 is filled with nitrogen 2 under pressure from a cylinder 19, while the lower part is filled with fluid 30 which, pushed by the piston 15, through a connecting conduit 5, under the action of valve means constituted by a valve shell 31 and by a variable-action breech 32, causes the advancement of a piston 7 of an auxiliary cylinder/piston unit 6, 7 provided with a Linear speed transducer 71.
- the cylindrical chamber 6 is filled in the front with fluid 40 which, pushed in a conduit 8 provided with a unidirectional valve 60 by the movement of the piston 7, causes the advancement of an injection piston 10 into a corresponding injection cylinder 9 provided with a rapid discharge valve 65 (of a type known in itself).
- a pressure multiplier 12 With the injection cylinder/piston unit 9, 10, provided with an injection stem 42, there is connected through a line 11, provided with a unidirectional valve 61, a pressure multiplier 12.
- the latter comprises an accumulator 13 consisting of a cylinder/piston 16, 17.
- the upper part of the cylindrical chamber 16 is filLed with nitrogen under pressure 18 which causes the sliding action of the piston 17, while the lower part of the chamber 16 is filled with fluid 50 which, pushed by the piston 17, through the line 51 under the action of valve means constituted by a valve shell 20 and a variable- action breech 21, causes the advancement of a cylinder/piston pair 53, 52 which in turn with fluid 54 causes the sliding action of the injection piston 10 in the corresponding cylinder 9.
- the molten mass present in the injection cylinder 9 is compressed by the stem 42 in the proximity of the injection mouth (not shown).
- the Larger diameter of the auxiliary cylinder 6 with respect to the injection cylinder 9 causes the speed of the auxiliary piston 7 during its stroke to be Lower than that of the injection piston 10 and thus easily controllable.
- the action of the pressure multiplier 12 then follows in a controlled manner.
- the piston 17, pushed by the nitrogen under pressure 18 present in the upper part of the cylinder 16 starts its stroke and pushes the fluid 50 into the line 51 under the action of the valve means 20, 21 and, through the cylinder/piston pair 53, 52 and the corresponding control fluid 54, causing the sliding action with the multiplication of the pressure of the injection piston 10 in the corresponding cylinder 9.
- the increase in ' pressure that occurs during this stage does not create undesired pressure peaks on the injection piston 10 and thus on the molten mass to be injected.
- at the end of this stage there is the restoration of the initial conditions for the pistons 15, 7, 10, 52, 17 in the respective cylinders 14, 6, 9, 53, 16.
- auxiliary piston 7 also operates in the ambit of the pressure multiplier 12.
- the piston 7 has a part with a smaller diameter which co-operates with the cylinder 6 supplied with fluid 30 from the accumulator 1 through a unidirectional valve 85 and communicating with the injection cylinder 9 through a valve 87 with a floating breech 88 and a part with a larger diameter which co-operates with a cylinder 86 supplied with fluid 50 from the accumulator 13 through the valve 20 with controlled breech 21 and communicating with the injection cylinder 9 through the unidirectional valve 61.
- Fig.s 5 - 8 also show two unidirectional valves 91 and 92 destined to the supply of fluid under pressure for recharging the accumulators 1 and 13 and a valve 93 with a floating breech 94 for discharging the fluid sent back by the injection piston 10 during the stages when it returns to the at rest position.
- the movement of opening of the breech 32 causes the supply of fluid 30 through the unidirectional valve 85 into the cylinder 6, where the piston 7 is thus caused to move forward so that, in turn, through the unidirectional valve 61, it causes the advancement of the injection piston 10 inside the injection cylinder 9 (with the valve 65 open ) for the stage of injection of the metal into the casting cavity (Fig. 6).
- the breech 21 is caused to open, allowing the transfer of high- pressure fluid from the accumulator 13 to the auxiliary cylinder 86, where the above fluid causes the auxiliary piston 7 to move backward and, due to the difference in area, the consequent creation of a multiplied pressure in the cylinder 6, which opens the valve 87 and goes to supply the injection piston 10 (Fig. 7). This creates the pressure multiplier effect on the molten metal pushed by the piston stem 42.
- valves 31, 32 and 21, 10 close again and thanks to the valve 65 the injection piston 10 is caused to return, thus discharging fluid through the valve 93 (Fig. 8).
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Injection Moulding Of Plastics Or The Like (AREA)
- Moulds For Moulding Plastics Or The Like (AREA)
- Molds, Cores, And Manufacturing Methods Thereof (AREA)
- Fluid-Pressure Circuits (AREA)
Abstract
L'ensemble d'injection comprend un cylindre d'injection (9), un piston à injection à fonctionnement hydraulique (10), un accumulateur de fluide (1) servant au fonctionnement à vitesse élevée du piston à injection (10) pendant la course d'injection et un multiplicateur de pression (12) servant au fonctionnement en vitesse lente et haute pression du piston (10) à la fin de la course d'injection du piston (10). Il comprend également un ensemble auxiliaire cylindre/piston (6, 7) intercalé entre le piston à injection (10) et l'accumulateur (1) pour permettre l'avancée du piston (7) dudit ensemble auxiliaire sous l'action de l'accumulateur (1) et l'avancée dudit piston à injection (10) par rapport à celle dudit piston auxiliaire (7). La section transversale du cylindre auxiliaire (6) est supérieure à celle du cylindre d'injection (9).The injection assembly includes an injection cylinder (9), a hydraulically operated injection piston (10), a fluid accumulator (1) for high speed operation of the injection piston (10) during the stroke injection and a pressure multiplier (12) for operating at low speed and high pressure of the piston (10) at the end of the injection stroke of the piston (10). It also includes an auxiliary cylinder / piston assembly (6, 7) interposed between the injection piston (10) and the accumulator (1) to allow the advance of the piston (7) of said auxiliary assembly under the action of the accumulator (1) and the advance of said injection piston (10) relative to that of said auxiliary piston (7). The cross section of the auxiliary cylinder (6) is greater than that of the injection cylinder (9).
Description
Claims
Applications Claiming Priority (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
IT2039490 | 1990-05-22 | ||
IT02039490A IT1248476B (en) | 1990-05-22 | 1990-05-22 | INJECTION GROUP FOR HYDRAULIC DIE-CASTING MACHINE, EQUIPPED WITH A DEVICE FOR THE ELIMINATION OF INJECTION PRESSURE PEAKS |
PCT/EP1991/000913 WO1991017850A1 (en) | 1990-05-22 | 1991-05-15 | Injection unit for a hydraulic die-casting machine, provided with a device for the elimination of pressure peaks at injection |
Publications (2)
Publication Number | Publication Date |
---|---|
EP0530244A1 true EP0530244A1 (en) | 1993-03-10 |
EP0530244B1 EP0530244B1 (en) | 1996-01-10 |
Family
ID=11166319
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP91909466A Expired - Lifetime EP0530244B1 (en) | 1990-05-22 | 1991-05-15 | Injection unit for a hydraulic die-casting machine, provided with a device for the elimination of pressure peaks at injection |
Country Status (7)
Country | Link |
---|---|
EP (1) | EP0530244B1 (en) |
CN (1) | CN1056643A (en) |
AT (1) | ATE132781T1 (en) |
DE (1) | DE69116361T2 (en) |
ES (1) | ES2080948T3 (en) |
IT (1) | IT1248476B (en) |
WO (1) | WO1991017850A1 (en) |
Families Citing this family (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN101774004B (en) * | 2009-01-12 | 2012-05-23 | 深圳领威科技有限公司 | Oil-electric hybrid hot-chamber die casting machine injection system |
CN101774005B (en) * | 2009-01-12 | 2012-05-30 | 深圳领威科技有限公司 | Oil-electric hybrid cold-chamber die casting machine injection system |
CN101530902B (en) * | 2009-04-16 | 2010-12-08 | 宁海县德科模塑有限公司 | Stable-pressure device of Zinc alloy die casting mold |
CN102451899A (en) * | 2010-10-25 | 2012-05-16 | 上海一达机械有限公司 | Oil pump driving device for pump station of hydraulic system in die casting machine |
Family Cites Families (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE2021539B2 (en) * | 1970-05-02 | 1971-04-22 | Wotan Werke Gmbh | DIE CASTING MACHINE WITH MULTIPLIER |
DE3014868A1 (en) * | 1979-06-18 | 1981-01-22 | Buehler Ag Geb | DIE CASTING MACHINE |
DE3123498C1 (en) * | 1981-06-13 | 1983-02-03 | Maschinenfabrik Müller-Weingarten AG, 7987 Weingarten | Device for the accelerated build-up and for the regulation of the squeezing pressure in die-casting machines |
-
1990
- 1990-05-22 IT IT02039490A patent/IT1248476B/en active IP Right Grant
-
1991
- 1991-05-15 ES ES91909466T patent/ES2080948T3/en not_active Expired - Lifetime
- 1991-05-15 AT AT91909466T patent/ATE132781T1/en active
- 1991-05-15 DE DE69116361T patent/DE69116361T2/en not_active Expired - Fee Related
- 1991-05-15 EP EP91909466A patent/EP0530244B1/en not_active Expired - Lifetime
- 1991-05-15 WO PCT/EP1991/000913 patent/WO1991017850A1/en active IP Right Grant
- 1991-05-22 CN CN91103431.5A patent/CN1056643A/en active Pending
Non-Patent Citations (1)
Title |
---|
See references of WO9117850A1 * |
Also Published As
Publication number | Publication date |
---|---|
DE69116361D1 (en) | 1996-02-22 |
ATE132781T1 (en) | 1996-01-15 |
IT1248476B (en) | 1995-01-19 |
WO1991017850A1 (en) | 1991-11-28 |
ES2080948T3 (en) | 1996-02-16 |
CN1056643A (en) | 1991-12-04 |
EP0530244B1 (en) | 1996-01-10 |
DE69116361T2 (en) | 1996-05-30 |
IT9020394A1 (en) | 1991-11-22 |
IT9020394A0 (en) | 1990-05-22 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
CA1109732A (en) | Free piston engine pump with energy rate smoothing | |
EP0772735B1 (en) | Free-piston engine | |
FR2595972A2 (en) | Percussion appliance | |
FR2676953A1 (en) | HYDRAULIC DEVICE WITH PERCUSSIONS. | |
JPH07501122A (en) | Free piston engine with fluid pressurization device | |
FR2749346A1 (en) | HYDRAULIC VALVE CONTROL DEVICE WITH FREE CONTROL | |
US3891126A (en) | Injection cylinders of die cast machines | |
JP2645942B2 (en) | Method and apparatus for controlling supply and exhaust valves of an internal combustion engine | |
FR2354464A1 (en) | FLUID CIRCUIT INCLUDING A CONTROL MECHANISM | |
EP0530244B1 (en) | Injection unit for a hydraulic die-casting machine, provided with a device for the elimination of pressure peaks at injection | |
JP4152744B2 (en) | Automatic lubricator | |
US7210514B2 (en) | Die casting machine | |
FR3052824A1 (en) | DEVICE FOR DIRECTLY RECOVERING HYDRAULIC ENERGY USING A SINGLE EFFECT HYDRAULIC CYLINDER | |
FR2522080A1 (en) | TRAINING FOR A MOBILE MASS USING A HYDRAULIC ENGINE | |
US4150603A (en) | Fluid operable hammer | |
JP2003112248A (en) | Injection method for die-casting machine | |
JPH0794061B2 (en) | Injection molding machine drive | |
US4244274A (en) | Cylinder control device of hydraulic cylinder apparatus | |
JP7392523B2 (en) | Die casting method and control device | |
AU678665B2 (en) | Accumulator charging system | |
SU1207688A1 (en) | Axial effort actuator of friction-welding machine | |
SU1094918A1 (en) | Ripper | |
JPH0337933Y2 (en) | ||
FR2562611A1 (en) | Method for supplying hydraulic jacks and hydraulic jacks implementing the method | |
SU1742417A1 (en) | Air-hydraulic soil compactor |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
PUAI | Public reference made under article 153(3) epc to a published international application that has entered the european phase |
Free format text: ORIGINAL CODE: 0009012 |
|
AK | Designated contracting states |
Kind code of ref document: A1 Designated state(s): AT BE CH DE DK ES FR GB GR IT LI LU NL SE |
|
18D | Application deemed to be withdrawn |
Effective date: 19931201 |
|
17P | Request for examination filed |
Effective date: 19920220 |
|
D18D | Application deemed to be withdrawn (deleted) | ||
17Q | First examination report despatched |
Effective date: 19950620 |
|
GRAA | (expected) grant |
Free format text: ORIGINAL CODE: 0009210 |
|
AK | Designated contracting states |
Kind code of ref document: B1 Designated state(s): AT BE CH DE DK ES FR GB GR IT LI LU NL SE |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: NL Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 19960110 Ref country code: GR Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 19960110 Ref country code: DK Effective date: 19960110 Ref country code: BE Effective date: 19960110 Ref country code: AT Effective date: 19960110 |
|
REF | Corresponds to: |
Ref document number: 132781 Country of ref document: AT Date of ref document: 19960115 Kind code of ref document: T |
|
ITF | It: translation for a ep patent filed |
Owner name: SOCIETA' ITALIANA BREVETTI S.P.A. |
|
ET | Fr: translation filed | ||
REG | Reference to a national code |
Ref country code: ES Ref legal event code: FG2A Ref document number: 2080948 Country of ref document: ES Kind code of ref document: T3 |
|
REF | Corresponds to: |
Ref document number: 69116361 Country of ref document: DE Date of ref document: 19960222 |
|
REG | Reference to a national code |
Ref country code: CH Ref legal event code: NV Representative=s name: PATENTANWAELTE GEORG ROEMPLER UND ALDO ROEMPLER |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: SE Effective date: 19960410 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: GB Effective date: 19960515 |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: FR Payment date: 19960515 Year of fee payment: 6 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: LU Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 19960531 Ref country code: LI Effective date: 19960531 Ref country code: CH Effective date: 19960531 |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: ES Payment date: 19960531 Year of fee payment: 6 |
|
NLV1 | Nl: lapsed or annulled due to failure to fulfill the requirements of art. 29p and 29m of the patents act | ||
PLBE | No opposition filed within time limit |
Free format text: ORIGINAL CODE: 0009261 |
|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT |
|
26N | No opposition filed | ||
GBPC | Gb: european patent ceased through non-payment of renewal fee |
Effective date: 19960515 |
|
REG | Reference to a national code |
Ref country code: CH Ref legal event code: PL |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: ES Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 19970516 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: FR Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 19980130 |
|
REG | Reference to a national code |
Ref country code: FR Ref legal event code: ST |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: DE Payment date: 19990528 Year of fee payment: 9 |
|
REG | Reference to a national code |
Ref country code: ES Ref legal event code: FD2A Effective date: 19990503 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: DE Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20010301 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: IT Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES;WARNING: LAPSES OF ITALIAN PATENTS WITH EFFECTIVE DATE BEFORE 2007 MAY HAVE OCCURRED AT ANY TIME BEFORE 2007. THE CORRECT EFFECTIVE DATE MAY BE DIFFERENT FROM THE ONE RECORDED. Effective date: 20050515 |