Pressure intensifier device for die casting machine and pressure intensifying method

Abstract

The application discloses a die casting machine pressurizing device and pressurizing method, and relates to the technical field of die casting machines, which comprises a pressurizing oil cylinder, the pressurizing oil cylinder is provided with a piston rod, a pressurizing rodless cavity, a pressurizing rod cavity and a pressurizing piston rod cavity; the pressurizing rodless cavity of the pressurizing oil cylinder is connected with an auxiliary accumulator, the auxiliary accumulator is provided with an accumulator air cavity and an accumulator oil cavity, wherein the accumulator air cavity of the auxiliary accumulator is connected with the pressurizing rodless cavity of the pressurizing oil cylinder, and the accumulator oil cavity of the auxiliary accumulator is connected with a pre-charging pressure source through an accumulator oil control valve; the pressurizing rod cavity of the pressurizing oil cylinder is connected with an oil tank through an oil liquid control valve; and the pressurizing piston rod cavity of the pressurizing oil cylinder is connected with the oil tank through a pressurizing oil return valve; thus, the pressurizing oil cylinder can have sufficient pressure without complicated dynamic control operation, and the whole injection process can have sufficient pressurizing pressure.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of die casting machines, in particular to a die casting machine supercharging device and supercharging method. BACKGROUND

[0002] A die casting machine is used to inject metal liquid into a mold cavity of a mold through a pressure injection cylinder as an accumulator, so as to form a die casting. During the metal liquid forming process, a counterforce is applied to the pressure injection cylinder, and generally, the pressure at the rear end of the pressure injection cylinder (i.e., supercharging) needs to be increased during the high-speed injection stage to ensure sufficient casting pressure for the metal liquid to be formed under a certain pressure, thereby improving the quality of the die casting.

[0003] In practice, when the supercharging is performed until the end of the fast injection, the pressure in the pressure injection cylinder piston chamber will sharply rise. When the pressure in the pressure injection cylinder piston chamber reaches a set pressure or when the pressure injection switch rod reaches a set position, the compressed nitrogen in the supercharging rodless chamber (i.e., nitrogen chamber) of the pressure injection cylinder is quickly released, and the oil in the supercharging rod chamber (i.e., oil chamber) of the pressure injection cylinder returns to the oil tank, thereby pushing the supercharging piston to move forward quickly. This process uses the area ratio of the supercharging cylinder piston and the piston rod to amplify the force of the pressure injection cylinder. The pressure in the supercharging cylinder piston chamber needs to be dynamically controlled and adjusted in real time.

[0004] However, since the pressure in the supercharging rod chamber (i.e., oil chamber) is constantly changing, a proportional servo valve is required to adjust in real time according to the dynamic response. The PLC control precision and the response and control precision of the proportional servo valve are required to be high, and the pressure oil flow entering the supercharging rod chamber (i.e., oil chamber) is also required to be high. In actual work, the repeatability of this injection process is difficult to be completely consistent, which leads to high design and manufacturing costs of the machine. SUMMARY

[0005] The present application aims to at least solve one of the technical problems existing in the prior art. To this end, the present application provides a die casting machine supercharging device and supercharging method.

[0006] The technical solution adopted by the present invention to solve its technical problems is: to provide a die-casting machine boosting device, including a boosting oil cylinder, the boosting oil cylinder has a piston rod, a boosting rodless chamber, a boosting rod chamber, and a boosting piston rod chamber; the boosting rodless chamber of the boosting oil cylinder is connected to an auxiliary accumulator, and the auxiliary accumulator has an accumulator air chamber and an accumulator oil chamber, wherein the accumulator air chamber of the auxiliary accumulator is connected to the boosting rodless chamber of the boosting oil cylinder, and the accumulator oil chamber of the auxiliary accumulator is connected to a pre-charge pressure source through an accumulator oil control valve; the boosting rod chamber of the boosting oil cylinder is connected to an oil tank through a boosting return oil valve, and the boosting return oil valve controls the oil in the boosting rod chamber to flow back to the oil tank through a boosting quick exhaust valve; and also includes a shot cylinder, which has The piston rod, the injection rod chamber, the injection rodless chamber, the injection cylinder and the oil tank are connected with an injection control valve, the injection control valve realizes the control of uniform speed, uniform acceleration slow injection, fast injection, and braking multi-stage injection speed through the injection oil cylinder quick-displacement proportional servo valve, realizes real-time control function, and prevents the pilot valve return oil back pressure through the quick-displacement proportional servo valve pilot return oil valve, and the separate return oil is not affected by other pipelines and back pressure; the boost rod chamber and the boost piston rod chamber of the boost cylinder are connected to the pre-charge pressure source through the boost control valve; a first return oil electric regulating valve is also provided between the boost piston rod chamber and the boost control valve; the oil control valve controls the boost piston rod chamber oil to flow to the injection chamber of the injection cylinder through the boost valve, and the boost pilot solenoid valve is used as the pilot solenoid valve for controlling the boost valve.

[0007] The die-casting machine boosting device provided by the present invention has at least the following technical effects by adopting a design that cooperates with a boosting cylinder and an auxiliary accumulator: in this way, there is no need for overly complicated dynamic control operations, and it can be ensured that the boosting cylinder can have sufficient pressure, ensuring that there is sufficient boosting pressure throughout the injection process.

[0008] As some preferred embodiments of the present invention, the die-casting machine boosting device further includes a first injection oil return valve connected to the pre-charge pressure source.

[0009] As some preferred embodiments of the present invention, the die-casting machine boosting device further includes a second injection oil return valve connected to the pre-charge pressure source.

[0010] As some preferred embodiments of the present invention, the die-casting machine boosting device further includes a second energy accumulator.

[0011] A die-casting machine pressurization method according to a second embodiment of the present invention employs the above-mentioned die-casting machine pressurization device, and the steps include:

[0012] (a) Before the injection starts, the accumulator oil chamber is pre-charged with nitrogen pressure P1 through the accumulator oil control valve, and the pressure of the pressurized rodless chamber, the accumulator gas chamber and the accumulator oil chamber is consistent, then the pressurized rod chamber and the pressurized piston rod chamber are stored through the pressurization control valve, and the pre-charged nitrogen pressure P1 is reached;

[0013] (b) When the injection starts, the pressure of the injection cylinder piston chamber sharply rises when the injection in step (a) is about to end, and when the pressure of the injection cylinder piston chamber reaches the set pressure or when the injection switch rod reaches the set position, the oil control valve and the pressurized return valve are simultaneously powered on, the compressed nitrogen in the pressurized rodless chamber is quickly released, and the oil in the pressurized rod chamber returns to the tank through the pressurized quick exhaust valve of the pressurized return valve, so as to push the piston rod of the pressurized oil cylinder forward quickly, and the area ratio of the piston and the piston rod of the pressurized oil cylinder is used to realize the amplification of the thrust of the injection cylinder.

[0014] As some preferred embodiments of the present application, before step (a), the required pressurization pressure is calculated through PLC, and the nitrogen pressure P1 released by the pressurized accumulator is converted according to the pressurization pressure.

[0015] The beneficial effects of the present application are: by adopting the design of the pressurized oil cylinder cooperating with the auxiliary accumulator, sufficient pressure of the pressurized oil cylinder can be ensured without too complex dynamic control operation, and sufficient pressurization pressure during the whole injection process is ensured.

[0016] Additional aspects and advantages of the present application will be partially given in the following description, partially will become obvious from the following description, or will be understood by the practice of the application. BRIEF DESCRIPTION OF DRAWINGS

[0017] Additional aspects and advantages of the present application will become apparent and readily understood from the following description, in connection with the accompanying drawings, in which:

[0018] Figure 1 is a structural schematic diagram of the present application.

[0019] Reference signs:

[0020] The pressurized oil cylinder 100, the auxiliary accumulator 200 and the injection cylinder 300;

[0021] The pressurized rodless chamber D1, the pressurized rod chamber D2, the pressurized piston rod chamber D3, the injection rodless chamber D4, the injection rod chamber D5, the accumulator gas chamber D6 and the accumulator oil chamber D7;

[0022] The injection cylinder fast discharge proportional servo valve V1, the fast discharge proportional servo valve pilot return valve V2, the slow injection valve V3, the slow injection pilot electromagnetic valve V4, the fast injection valve V5, the fast injection pilot electromagnetic valve V6, the fast injection valve pilot return valve V7, the fast injection accumulator energy storage valve V8, the pressure boost control valve V9, the first return valve V12, the pressure boost rod cavity one-way valve V13, the pressure boost fast discharge valve V21, the pressure boost pilot electromagnetic valve V22, the pressure boost fast discharge valve pilot return V23, the accumulator oil control valve V24;

[0023] The injection control valve S1, the first injection return valve S2, the second injection return valve S3, the oil control valve S6, the pressure boost return valve S9.

[0024] The pre-charging pressure source P, the oil tank T, the second accumulator ACC1. DETAILED DESCRIPTION

[0025] The embodiments of the present application are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar notations represent the same or similar elements or elements having the same or similar functions throughout. The embodiments described below by referring to the drawings are exemplary only, for the purpose of explaining the present application, and should not be understood as a limitation of the present application.

[0026] In the description of the present application, it should be understood that the orientation description, such as the orientation or position relationship indicated by up, down, front, back, left, right, etc. is based on the orientation or position relationship shown in the drawings, and is only for the convenience of describing the present application and simplifying the description, and therefore cannot be understood as a limitation of the present application, which does not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation of the present application.

[0027] In the description of the present application, the meaning of multiple is more than two, greater than, less than, more than, etc. is not included in the number. If it is described as first, second, it is only for the purpose of distinguishing technical features, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated or the sequence of technical features indicated.

[0028] In the description of the present application, unless otherwise explicitly limited, the words such as setting, mounting, connecting, etc. should be understood in a broad sense, and the person skilled in the art can reasonably determine the specific meaning of the above words in the present application in combination with the specific content of the technical solution.

[0029] Figure 1 is a structural schematic diagram of one embodiment of the present application, with reference to Figure 1 One embodiment of the present application provides a pressure boost device for a die casting machine, which comprises a pressure boost cylinder 100, the pressure boost cylinder 100 having a piston rod, a pressure boost rodless cavity D1, a pressure boost rod cavity D2, and a pressure boost piston rod cavity D3.

[0030] Further, the pressurized rodless chamber D1 of the pressurized cylinder 100 is connected with an auxiliary accumulator 200, the auxiliary accumulator 200 has an accumulator air chamber D6 and an accumulator oil chamber D7, wherein the accumulator air chamber D6 of the auxiliary accumulator 200 is connected with the pressurized rodless chamber D1 of the pressurized cylinder 100, and the accumulator oil chamber D7 of the auxiliary accumulator 200 is connected with the pre-charging pressure source P through an accumulator oil control valve V24.

[0031] Further, the pressurized rod chamber D2 of the pressurized cylinder 100 is connected with the oil tank T through a pressurized oil return valve S9, and the pressurized process of the pressurized cylinder 100 is controlled.

[0032] Further, the pressurized rod chamber D2 and the pressurized piston rod chamber D3 of the pressurized cylinder 100 are connected with the pre-charging pressure source P through a pressurized control valve V9.

[0033] Further, a first oil return electric valve V12 is arranged between the pressurized piston rod chamber D3 and the pressurized control valve V9, and is responsible for energy storage and pressure maintenance of the pressurized piston rod chamber D3.

[0034] In actual work, the nitrogen pressure P1 after the release of the pressurized cylinder 100 is preset and calculated, and then the pre-charging pressure source P pre-charges the accumulator oil chamber D7 of the auxiliary accumulator 200. The auxiliary accumulator 200 and the pressurized cylinder 100 realize dynamic adjustment of pressure.

[0035] When the "pressurization" in the man-machine interface injection page on the electric box panel selects "use", when the fast injection is about to end, the pressure of the injection cylinder piston chamber will rise sharply, when the pressure of the injection cylinder piston chamber reaches the set pressure or when the injection switch rod reaches the set position, the oil control valve S6 and the pressurized oil return valve S9 work at the same time, the compressed nitrogen in the pressurized rodless chamber D1 of the pressurized cylinder 100 is quickly released, the oil in the pressurized rod chamber D2 returns to the oil tank T through the first oil return electric valve V12, and the pressurized piston is pushed forward quickly, and the area ratio of the pressurized cylinder piston and the piston rod is used to realize the amplification of the injection cylinder force.

[0036] In some embodiments, the pressurized device of the die casting machine further comprises an injection cylinder 300, the injection cylinder 300 has a piston rod, an injection rod chamber D5 and an injection rodless chamber D4.

[0037] In this embodiment, the injection cylinder 300 is connected with the oil tank T through an injection control valve S1, the injection control valve S1 controls the uniform speed, uniform acceleration slow injection, fast injection, brake and other multi-stage injection speeds through the injection cylinder fast discharge proportional servo valve V1, realizes the real-time control function, and prevents the back pressure of the pilot valve through the fast discharge proportional servo valve pilot return valve V2, and the separate oil return is not affected by other pipelines and back pressure.

[0038] Some embodiments, the pressure casting machine supercharging device further comprises a second accumulator ACC1 as a backup accumulator. The second accumulator ACC1 is controlled by the fast injection accumulator energy storage valve V8 to store energy from the oil pump to the second accumulator ACC1.

[0039] Some embodiments, the pressure casting machine supercharging device further comprises a first injection return valve S2 connected to the pre-charging pressure source P.

[0040] In this embodiment, the first injection return valve S2 is controlled by the slow injection valve V3 as the slow injection action valve of the oil cylinder, and the slow injection pilot solenoid valve V4 is used as the pilot solenoid valve to control the slow injection valve V3.

[0041] Some embodiments, the pressure casting machine supercharging device further comprises a second injection return valve S3 connected to the pre-charging pressure source P.

[0042] In this embodiment, the second injection return valve S3 is controlled by the fast injection valve V5 to control the oil flow from the second accumulator ACC1 to the injection cylinder 300 (high flow), the fast injection pilot solenoid valve V6 is used as the pilot solenoid valve to control the fast injection valve V5, and the fast injection valve pilot return valve V7 is used to prevent the back pressure of the pilot valve return oil, ensuring that the separate return oil is not affected by other pipelines and back pressure.

[0043] Some embodiments, the oil control valve S6 controls the oil flow from the supercharging piston rod cavity D3 to the injection cavity of the injection cylinder 300 through the supercharging valve V10, and the supercharging pilot solenoid valve V11 is used as the pilot solenoid valve to control the supercharging valve V10.

[0044] Some embodiments, the supercharged rod cavity D2 is provided with a supercharged rod cavity one-way valve V13 between the supercharged rod cavity D2 and the supercharged control valve V9, which is responsible for storing energy and maintaining pressure in the supercharged rod cavity D2.

[0045] Some embodiments, the supercharged return valve S9 controls the oil return from the supercharged rod cavity D2 to the oil tank T through the supercharged fast discharge valve V21, the supercharged pilot solenoid valve V22 is used as the pilot solenoid valve to control the supercharged fast discharge valve V21, and the supercharged fast discharge valve pilot return V23 is used to prevent the back pressure of the pilot valve return oil, avoiding the separate return oil not affected by other pipelines and back pressure.

[0046] Some embodiments, a pressure casting machine supercharging method is adopted in the above-mentioned pressure casting machine supercharging device, and the steps include:

[0047] (a) Before the injection starts, the accumulator oil cavity is pre-charged with nitrogen pressure P1 through the accumulator oil control valve V24, the pressure of the supercharged rod cavity D1, the accumulator gas cavity D6, and the accumulator oil cavity D7 is consistent, and then the supercharged rod cavity D2 and the supercharged piston rod cavity D3 are stored and supercharged through the supercharged control valve V9, reaching the pre-charged nitrogen pressure P1;

[0048] (b) When the boost starts, the pressure in the piston chamber of the injection cylinder 300 will rise sharply when the injection is almost finished. When the pressure in the piston chamber of the injection cylinder 300 reaches the set pressure or when the injection switch rod reaches the set position, the oil control valve S6 and the boost return valve S9 are energized at the same time, the compressed nitrogen in the boost rodless chamber D1 is quickly released, the oil in the boost rod chamber D2 is returned to the tank T through the boost quick exhaust valve V21 in the boost return valve S9, and the piston rod of the boost cylinder 100 is pushed forward quickly, and the area ratio of the piston and the piston rod of the boost cylinder 100 is used to realize the amplification of the thrust of the injection cylinder 300.

[0049] In some embodiments, before step (a), the required boost pressure is calculated by PLC, and the nitrogen pressure P1 released by the boost accumulator is converted according to the boost pressure.

[0050] In the description of the present specification, the description of the terms "some embodiments" or "it is conceivable that" and the like means that the specific features, structures, materials or characteristics described in conjunction with the embodiments or examples are included in at least one embodiment or example of the present application. In the present specification, the illustrative description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0051] Although the embodiments of the present application have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and variations can be made to the embodiments without departing from the principles and spirit of the present application, and the scope of the present application is defined by the claims and their equivalents.

Claims

1. A die casting machine pressurizing device, comprising a pressurizing cylinder (100), the pressurizing cylinder (100) having a piston rod, a pressurizing rodless cavity (D1), a pressurizing rod cavity (D2), a pressurizing piston rod cavity (D3), characterized in that: the pressurizing rodless cavity (D1) of the pressurizing cylinder (100) is connected with an auxiliary accumulator (200), the auxiliary accumulator (200) having an accumulator gas cavity (D6), an accumulator oil cavity (D7), wherein the accumulator gas cavity (D6) of the auxiliary accumulator (200) is connected with the pressurizing rodless cavity (D1) of the pressurizing cylinder (100), and the accumulator oil cavity (D7) of the auxiliary accumulator (200) is connected with a pre-charging pressure source (P) through an accumulator oil control valve (V24); the pressurizing rod cavity (D2) of the pressurizing cylinder (100) is connected with an oil tank (T) through a pressurizing return valve (S9), and the pressurizing return valve (S9) controls the oil return of the pressurizing rod cavity (D2) to the oil tank (T) through a pressurizing quick exhaust valve (V21); further comprising a shot cylinder (300), the shot cylinder (300) having a piston rod, a shot rodless cavity (D4), and a shot rod cavity (D5), the shot cylinder (300) being connected with a shot control valve (S1) and an oil tank (T), the shot control valve (S1) realizing a multi-stage shot speed of uniform speed, uniform acceleration slow shot, fast shot, and brake through a shot cylinder quick exhaust proportional servo valve (V1), realizing a real-time control function, and preventing a pilot valve return oil back pressure through a quick exhaust proportional servo valve pilot return valve (V2), and the single oil return is not affected by other pipelines and back pressure; the pressurizing rod cavity (D2) and the pressurizing piston rod cavity (D3) of the pressurizing cylinder (100) are connected with the pre-charging pressure source (P) through a pressurizing control valve (V9); a first return oil electric valve (V12) is further arranged between the pressurizing piston rod cavity (D3) and the pressurizing control valve (V9); an oil control valve (S6) controls the oil flow of the pressurizing piston rod cavity (D3) to the shot cavity of the shot cylinder (300) through a pressurizing valve (V10), and a pressurizing pilot electromagnetic valve (V11) is used as a pilot electromagnetic valve of the pressurizing valve (V10).

2. A pressurization device for a die casting machine according to claim 1, characterized in that: a first shot return valve (S2) is further connected with the pre-charging pressure source (P).

3. A pressurization device for a die casting machine according to claim 1, characterized in that: a second shot return valve (S3) is further connected with the pre-charging pressure source (P).

4. A pressurization device for a die casting machine according to claim 1, characterized in that: a second energy accumulator (ACC1) is further included.

5. A method of pressurizing a die casting machine, characterized by, The die casting machine pressurizing device according to claim 1 is adopted, and the steps comprise: (a) before the shot starts, the accumulator oil cavity is pre-charged with nitrogen pressure P1 through the accumulator oil control valve (V24), the pressures of the pressurizing rodless cavity (D1), the accumulator gas cavity (D6), and the accumulator oil cavity (D7) are consistent, and then the pressurizing rod cavity (D2) and the pressurizing piston rod cavity (D3) are energized through the pressurizing control valve (V9) to reach the pre-charged nitrogen pressure P1. (b) When the pressure of the injection cylinder (300) piston chamber sharply rises at the end of the injection of step (a), the oil control valve (S6) and the pressure boost return valve (S9) are powered at the same time when the pressure of the injection cylinder (300) piston chamber reaches the set pressure or when the injection switch rod reaches the set position, the compressed nitrogen in the pressure boost rodless chamber (D1) is quickly released, the oil in the pressure boost rod chamber (D2) returns to the tank (T) through the pressure boost quick exhaust valve (V21) on the pressure boost return valve (S9), and the piston rod of the pressure boost cylinder (100) is quickly pushed forward to achieve the amplification of the thrust of the injection cylinder (300) by using the area ratio of the piston and the piston rod of the pressure boost cylinder (100).

6. A method of pressurizing a die casting machine according to claim 5, characterized in that: Before step (a), the required pressure boost pressure is calculated by PLC, and the nitrogen pressure P1 after the release of the pressure boost accumulator is converted according to the pressure boost pressure.

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