CN114570909A - Method and system for controlling extrusion speed and pressure in injection process of extrusion casting machine - Google Patents
Method and system for controlling extrusion speed and pressure in injection process of extrusion casting machine Download PDFInfo
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- CN114570909A CN114570909A CN202210483688.8A CN202210483688A CN114570909A CN 114570909 A CN114570909 A CN 114570909A CN 202210483688 A CN202210483688 A CN 202210483688A CN 114570909 A CN114570909 A CN 114570909A
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
- B22D18/00—Pressure casting; Vacuum casting
- B22D18/02—Pressure casting making use of mechanical pressure devices, e.g. cast-forging
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- B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
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Abstract
The invention discloses a method and a system for controlling extrusion speed and pressure in the injection process of an extrusion casting machine, which relate to the field of extrusion casting machines.
Description
Technical Field
The invention relates to the field of extrusion casting machines, in particular to a method and a system for controlling extrusion speed and pressure of an extrusion casting machine in an injection process.
Background
With the vigorous development of the new energy automobile industry in China and the continuous progress of the extrusion casting production process, the die casting industry puts forward more updated, stricter and more complex requirements on the injection performance and the function of the extrusion casting machine. The real-time control of the extrusion speed and the casting pressure of the extrusion casting machine in the extrusion process plays a crucial role in improving the quality and the precision of castings.
In the speed control stage of the traditional extrusion casting machine, the oil flow is changed by directly setting the opening degree of a valve port of an inlet proportional valve, so that the extrusion speed is changed, but the specific extrusion speed is unclear, the opening degree of the valve port of the inlet proportional valve needs to be repeatedly set by an experienced operator for a large part, the speed can reach the desired speed value after observing a speed measurement curve, and the speed change can be influenced by environmental factors such as subsequent oil level rise; when the pressure is emitted to the pressurization position, a pressurization control stage is carried out, the oil flow is changed mainly by changing the opening degree of a valve port of the inlet proportional valve in the pressurization stage, so that the pressurization speed and the pressure building time are changed, and the optimal opening degree of the inlet proportional valve can be obtained only by repeated tests of experienced operators. In addition, when the casting pressure is changed, the energy storage value of the energy accumulator and the nitrogen charging and discharging mode need to be changed, the process is troublesome, and an experienced operator is needed to complete the process. In summary, the conventional speed control mode and the conventional pressurization control mode are both open-loop control modes, the time for debugging process parameters is long, and the process can be completed by operators with certain experience, so that the process is not easy to use by new operators.
The invention provides a control method and a control system for continuously and accurately controlling the extrusion speed and the casting pressure.
Disclosure of Invention
In order to solve the problem that the extrusion speed and the casting pressure of a squeeze casting machine cannot be continuously and accurately controlled in the injection process, the invention provides a method for controlling the extrusion speed and the extrusion pressure of the squeeze casting machine in the injection process, which controls the opening of a pre-hammer servo valve connected with an injection piston device by acquiring the inlet pressure and the outlet pressure of the injection piston device in the squeeze casting machine so as to adjust the oil flow of an oil path, wherein the injection piston device comprises an injection oil cylinder inlet, an injection piston rod and an injection oil cylinder outlet which are sequentially arranged; the control method comprises the following steps:
s1: in the speed control stage, a voltage control signal corresponding to the injection speed set value is obtained through a valve speed control model, the opening of the pre-hammer servo valve is controlled through the voltage control signal, the real-time speed of the injection piston rod is obtained in the process, PID control is carried out according to the real-time speed so as to adjust the voltage control signal in real time, and the opening of the pre-hammer servo valve is adjusted according to the adjusted voltage control signal so that the speed of the injection piston rod reaches the injection speed set value;
s2: in the speed control process, acquiring the real-time position distance of the injection piston rod, the casting pressure of the extrusion casting machine and the real-time speed of the injection piston rod, and entering a pressurization control stage when the real-time position distance is greater than or equal to a pressurization set position distance, the casting pressure is greater than a pressure set value and the real-time speed is less than a pressure injection speed set value; the real-time position distance is the distance from an original point to the real-time position of the injection piston rod, and the original point is a position point where the injection piston rod is not injected;
s3: in the pressurization control stage, a voltage control signal corresponding to a pressure set value is obtained through a valve pressure control model, the opening of the pre-hammer servo valve is controlled through the voltage control signal, in the process, the real-time pressure of an inlet of the injection oil cylinder and the real-time pressure of an outlet of the injection oil cylinder are obtained, PID control is carried out according to the real-time pressure so as to adjust the voltage control signal in real time, and the opening of the pre-hammer servo valve is adjusted according to the adjusted voltage control signal so that the casting pressure of the extrusion casting machine can reach the pressure set value.
Further, the method for acquiring the valve speed control model comprises the following steps:
setting a plurality of test voltages, controlling the opening of a servo valve in front of the hammer according to the test voltages to acquire the speed of each test voltage corresponding to the injection piston rod, and acquiring a valve speed control model according to the linear relation between each test voltage and the speed of the corresponding injection piston rod.
Further, the method for acquiring the valve pressure control model comprises the following steps:
setting a plurality of test voltages, acquiring a voltage build-up slope through the test voltages and the corresponding voltage build-up time, and acquiring a valve pressure control model according to a linear relation between the voltage build-up slope and the test voltages.
Further, the injection piston device further includes a hammer connected to the injection piston rod, and an injection piston disposed at a position from an inlet of the injection cylinder to the hammer direction and from an outlet of the injection cylinder to the hammer direction, and in step S2, the casting pressure of the squeeze casting machine is obtained according to the formula:
in the formula, the pressure of an inlet of an injection oil cylinder is obtained through a pressure sensor connected with the inlet of the injection oil cylinder; the pressure of the outlet of the injection oil cylinder is obtained through a pressure sensor connected with the outlet of the injection oil cylinder.
Further, the real-time speed and the real-time position distance of the injection piston rod are obtained through a displacement sensor arranged on the injection piston rod.
The invention also provides a control system for the extrusion speed and the extrusion pressure of the extrusion casting machine in the injection process, which comprises the following steps:
the injection piston device comprises an injection oil cylinder inlet, an injection piston rod and an injection oil cylinder outlet which are arranged in sequence; pressure sensors are arranged at the inlet of the injection oil cylinder and the outlet of the injection oil cylinder and are used for acquiring the real-time pressure of the inlet and the outlet of the injection oil cylinder; the injection piston rod is provided with a displacement sensor for acquiring the real-time speed and the real-time position distance of the injection piston rod; the real-time position distance is the distance from an original point to the real-time position of the injection piston rod, and the original point is a position point where the injection piston rod is not injected;
a system oil supply port;
the pre-hammer servo valve is arranged between the oil supply port of the system and the inlet of the injection oil cylinder;
a control module, comprising:
the speed control unit is used for acquiring a voltage control signal corresponding to the injection speed set value through the valve speed control model in a speed control stage, controlling the opening of the pre-hammer servo valve through the voltage control signal, performing PID control according to the real-time speed of the injection piston rod in the process to adjust the voltage control signal in real time, and adjusting the opening of the pre-hammer servo valve according to the adjusted voltage control signal to enable the speed of the injection piston rod to reach the injection speed set value;
the judging unit is used for entering a pressurization control stage when the real-time position distance of the injection piston rod is greater than or equal to a pressurization set position distance, the casting pressure of the extrusion casting machine is greater than a pressure set value, and the real-time speed of the injection piston rod is less than an injection speed set value in the speed control process;
and the pressure control unit acquires a voltage control signal corresponding to the pressure set value through the valve pressure control model in the pressurization control stage, controls the opening of the pre-hammer servo valve through the voltage control signal, performs PID (proportion integration differentiation) control according to the real-time pressure of the inlet and the outlet of the injection oil cylinder in the process so as to adjust the voltage control signal in real time, and adjusts the opening of the pre-hammer servo valve according to the adjusted voltage control signal so as to enable the casting pressure of the extrusion casting machine to reach the pressure set value.
Further, the injection piston device further comprises a hammer connected with the injection piston rod, and an injection piston arranged at a position from an inlet of the injection cylinder to the hammer direction and from an outlet of the injection cylinder to the hammer direction, and the casting pressure of the squeeze casting machine is obtained according to the formula:
further, the system further comprises:
an oil tank;
the third valve part and the fourth valve part are connected with the outlet of the injection oil cylinder in parallel;
the third valve part comprises a third electromagnetic valve, a third cartridge valve and a one-way valve; the control module is also used for opening the third cartridge valve through a third electromagnetic valve after injection so as to enable the injection piston rod to move downwards, namely return to the hammer;
the fourth valve component comprises a fourth solenoid valve and a fourth cartridge valve; and the control module is also used for opening the fourth cartridge valve through the fourth electromagnetic valve during speed control and pressurization control so as to enable oil in the outlet of the injection oil cylinder to flow back to the oil tank.
Further, the system further comprises:
the second valve component is simultaneously connected with the pre-hammer servo valve and the injection cylinder inlet and comprises a second electromagnetic valve and a second cartridge valve; the control module is also used for opening the second cartridge valve through the second electromagnetic valve after hammering, namely injection, so that oil in the inlet of the injection oil cylinder flows back to the oil tank.
Further, the system further comprises:
the first valve component is connected between a system oil supply port and the pre-hammer servo valve and comprises a first electromagnetic valve, a first cartridge valve and a one-way valve, and the one-way valve is arranged between the pre-hammer servo valve and the first cartridge valve; the control module is also used for opening the first cartridge valve through the first electromagnetic valve during speed control and pressurization control so as to lead oil of the system oil supply port to the injection piston device.
Compared with the prior art, the invention at least has the following beneficial effects:
(1) in the speed control stage, PID control is carried out on the real-time speed of the injection piston rod, closed-loop adjustment of the opening of the servo valve in front of the hammer is realized (the speed of the injection piston rod is enabled to reach an injection speed set value), so that continuous and accurate control on the injection speed is realized, the problem of speed change caused by environmental factors is solved, the problem that the target speed value can be reached after an experienced operator repeatedly sets the opening of a valve port of an inlet proportional valve and observes a speed measurement curve in the current speed control stage is avoided, and the casting efficiency is improved;
(2) in the pressurization control stage, PID control is carried out through real-time pressure of an inlet and an outlet of the injection oil cylinder, closed-loop adjustment of the opening of a servo valve before the hammer is realized (the casting pressure reaches a pressure set value), so that continuous and accurate control of the casting pressure is realized, the problems that the optimal opening of the inlet proportional valve and the target pressure value can be obtained only by repeatedly testing by experienced operators when the pressurization speed and the pressure building time are changed by changing the opening of a valve port of the inlet proportional valve in the pressurization control stage at present, and the storage energy value of an energy accumulator and the nitrogen charging and discharging mode need to be changed when the casting pressure is changed are solved, the process is troublesome and the casting efficiency can be greatly improved only by the experienced operators;
(3) according to the invention, PID control is respectively carried out on the speed and the casting pressure in the speed control stage and the pressurization control stage, so that the anti-interference capability of the system is improved, and the influence caused by the change of the speed and the pressure caused by the environment is solved;
(4) the invention realizes the closed-loop control of the speed and the casting pressure by one pre-hammer servo valve, and is more economical and convenient compared with the prior art that the speed and the pressure are respectively controlled by two pre-hammer servo valves.
Drawings
FIG. 1 is a flow chart of a method for controlling the extrusion speed and pressure of a squeeze casting machine during injection;
FIG. 2 is a diagram of an oil path of the squeeze casting machine.
Detailed Description
The following are specific embodiments of the present invention and are further described with reference to the drawings, but the present invention is not limited to these embodiments.
Example one
In order to realize continuous and accurate control of extrusion speed and casting pressure in a speed control stage and a pressurization control stage, as shown in fig. 1, the invention provides a control method of extrusion speed and pressure of a squeeze casting machine in an injection process, which controls the opening of a pre-hammer servo valve connected with an injection piston device by acquiring the inlet pressure and the outlet pressure of the injection piston device in the squeeze casting machine so as to adjust the oil flow of an oil path, wherein the injection piston device comprises an injection oil cylinder inlet, an injection piston rod and an injection oil cylinder outlet which are sequentially arranged; the control method comprises the following steps:
s1: in the speed control stage, a voltage control signal corresponding to the injection speed set value is obtained through a valve speed control model, the opening of a servo valve in front of the hammer is controlled through the voltage control signal, the real-time speed of an injection piston rod is obtained in the process, PID control is carried out according to the real-time speed so as to adjust the voltage control signal in real time, and the opening of the servo valve in front of the hammer is adjusted according to the adjusted voltage control signal so that the speed of the injection piston rod reaches the injection speed set value;
the valve speed control model is obtained by the following method:
setting a plurality of test voltages, controlling the opening of a servo valve in front of the hammer according to the test voltages so as to obtain the speed of each test voltage corresponding to the injection piston rod, and obtaining a valve speed control model according to the linear relation between each test voltage and the speed of the corresponding injection piston rod. When the model is subsequently used, the voltage control signal can be calculated by inputting the corresponding velocity (shot velocity set value).
S2: in the speed control process, acquiring the real-time position distance of the injection piston rod, the casting pressure of the extrusion casting machine and the real-time speed of the injection piston rod, and entering a pressurization control stage when the real-time position distance is greater than or equal to a pressurization set position distance, the casting pressure is greater than a pressure set value and the real-time speed is less than a pressure injection speed set value; the real-time position distance is the distance from an original point to the real-time position of the injection piston rod, and the original point is a position point where the injection piston rod is not injected;
the injection piston device further comprises a hammer connected with the injection piston rod, and an injection piston arranged at a position from an injection cylinder inlet to the hammer direction and from an injection cylinder outlet to the hammer direction, and in the step S2, the casting pressure of the extrusion casting machine is obtained according to the formula:
in the formula, the pressure of an inlet of an injection oil cylinder is obtained through a pressure sensor connected with the inlet of the injection oil cylinder; the pressure of the outlet of the injection oil cylinder is obtained through a pressure sensor connected with the outlet of the injection oil cylinder.
S3: in the pressurization control stage, a voltage control signal corresponding to a pressure set value is obtained through a valve pressure control model, the opening of the pre-hammer servo valve is controlled through the voltage control signal, in the process, the real-time pressure of an inlet of the injection oil cylinder and the real-time pressure of an outlet of the injection oil cylinder are obtained, PID control is carried out according to the real-time pressure so as to adjust the voltage control signal in real time, and the opening of the pre-hammer servo valve is adjusted according to the adjusted voltage control signal so that the casting pressure of the extrusion casting machine can reach the pressure set value.
In this embodiment, after the real-time pressures of the inlet and the outlet of the injection cylinder are obtained, the method further includes obtaining the real-time casting pressure of the squeeze casting machine through the real-time pressures of the inlet and the outlet of the injection cylinder (see the obtaining formula of the casting pressure of the squeeze casting machine), and performing PID control according to the real-time casting pressure to adjust the voltage control signal in real time.
The opening degree of the pre-hammer servo valve is controlled by the voltage control signal, specifically, assuming that the voltage control signal is 0-10V, the opening degree of the pre-hammer servo valve is 0% -100%, for example, if the voltage control signal with the voltage of 1V is given, the pre-hammer servo valve will be opened by 10%.
The valve pressure control model is obtained by the following method:
setting a plurality of test voltages, acquiring a voltage build-up slope through the test voltages and the corresponding voltage build-up time, and acquiring a valve pressure control model according to a linear relation between the voltage build-up slope and the test voltages.
Specifically, regarding the valve pressure control model, we need to test in advance, and given a corresponding voltage (test voltage), there are different voltage build-up times, and the voltage build-up is faster as the voltage is larger, and the slope of the voltage build-up is larger as the voltage build-up time is smaller. The method comprises the steps that different test voltages are tested, a linear relation model between the build-up voltage slope and the voltage can be finally obtained, namely a valve pressure control model, corresponding build-up time and pressure are input when the model is subsequently used, the slope value which needs to be output actually can be naturally calculated, and the valve pressure control model can calculate a voltage control signal according to the slope value.
The real-time speed and the real-time position distance of the injection piston rod are obtained through a displacement sensor arranged on the injection piston rod.
In the pressurization control stage, PID control is carried out through the real-time pressure of the inlet and the outlet of the injection oil cylinder, closed-loop adjustment of the opening of the servo valve before the hammer is realized (the casting pressure reaches a pressure set value), so that continuous and accurate control of the casting pressure is realized, the problems that the optimal opening of the inlet proportional valve and the target pressure value can be obtained only by repeatedly testing by experienced operators when the pressurization speed and the pressure building time are changed by changing the opening of the valve port of the inlet proportional valve in the pressurization control stage at present, and the problems that the process is troublesome and the process can be completed only by the experienced operators when the casting pressure is changed are solved, and the casting efficiency is greatly improved.
Example two
As shown in fig. 2, the present invention further provides a system for controlling the extrusion speed and pressure of a squeeze casting machine during injection, comprising:
the injection piston device comprises an injection oil cylinder inlet, an injection piston rod and an injection oil cylinder outlet which are arranged in sequence; pressure sensors are arranged at the inlet and the outlet of the injection oil cylinder and are used for acquiring the real-time pressure of the inlet and the outlet of the injection oil cylinder; the injection piston rod is provided with a displacement sensor for acquiring the real-time speed and the real-time position distance of the injection piston rod; the real-time position distance is the distance from an original point to the real-time position of the injection piston rod, and the original point is a position point of the injection piston rod when injection is not performed;
a system oil supply port;
the pre-hammer servo valve is arranged between the oil supply port of the system and the inlet of the injection oil cylinder;
a control module, comprising:
the speed control unit is used for acquiring a voltage control signal corresponding to the injection speed set value through the valve speed control model in a speed control stage, controlling the opening of the pre-hammer servo valve through the voltage control signal, performing PID control according to the real-time speed of the injection piston rod in the process to adjust the voltage control signal in real time, and adjusting the opening of the pre-hammer servo valve according to the adjusted voltage control signal to enable the speed of the injection piston rod to reach the injection speed set value;
the judging unit is used for entering a pressurization control stage when the real-time position distance of the injection piston rod is greater than or equal to a pressurization set position distance, the casting pressure of the extrusion casting machine is greater than a pressure set value, and the real-time speed of the injection piston rod is less than an injection speed set value in the speed control process;
the injection piston device also comprises a hammer connected with the injection piston rod and an injection piston arranged at the position of an injection oil cylinder inlet towards the hammer direction and an injection oil cylinder outlet towards the hammer direction, and the casting pressure of the extrusion casting machine is obtained according to the formula:
and the pressure control unit acquires a voltage control signal corresponding to the pressure set value through the valve pressure control model in the pressurization control stage, controls the opening of the pre-hammer servo valve through the voltage control signal, performs PID (proportion integration differentiation) control according to the real-time pressure of the inlet and the outlet of the injection oil cylinder in the process to adjust the voltage control signal in real time, and adjusts the opening of the pre-hammer servo valve according to the adjusted voltage control signal so as to enable the casting pressure of the extrusion casting machine to reach the pressure set value.
The system further comprises:
an oil tank;
the third valve part and the fourth valve part are connected with the outlet of the injection oil cylinder in parallel;
the third valve component comprises a third solenoid valve, a third cartridge valve and a one-way valve (H1 in FIG. 2); the control module is also used for opening the third cartridge valve through a third electromagnetic valve after injection so as to enable the injection piston rod to move downwards, namely to return to the hammer (namely the injection piston rod is reset, the injection piston rod needs to be reset after injection is completed each time, and injection can be performed in the following cycle);
the fourth valve component comprises a fourth solenoid valve and a fourth cartridge valve; and the control module is also used for opening the fourth cartridge valve through the fourth electromagnetic valve during speed control and pressurization control so as to enable oil in the outlet of the injection oil cylinder to flow back to the oil tank.
The system further comprises:
the second valve component is simultaneously connected with the pre-hammer servo valve and the injection cylinder inlet and comprises a second electromagnetic valve and a second cartridge valve; the control module is also used for opening the second cartridge valve through the second electromagnetic valve after hammering, namely injection, so that oil in the inlet of the injection oil cylinder flows back to the oil tank.
The injection finger-pressing piston rod moves upwards, and the hammer returning finger-pressing piston rod moves downwards.
The system further comprises:
a first valve member connected between the system oil supply port and the pre-hammer servo valve, and including a first solenoid valve, a first cartridge valve, and a check valve (H0 in fig. 2) provided between the pre-hammer servo valve and the first cartridge valve; the control module is also used for opening the first cartridge valve through the first electromagnetic valve during speed control and pressurization control so as to lead oil of the system oil supply port to the injection piston device.
It should be noted that the cartridge valve is mainly used for realizing on/off of an oil path, and when the cartridge valve is used in combination with an electromagnetic valve, the direction, pressure and flow of oil in a system can be controlled.
In this embodiment, the hammer front servo valve is further connected with an energy accumulator, and the energy accumulator is connected with an energy accumulator pressure sensor, and the specific connection mode is shown in fig. 2.
In fig. 2, C1 is a displacement sensor; p1 is an accumulator pressure sensor; p2 is a pressure sensor at the inlet of the injection oil cylinder; p3 is a pressure sensor at the outlet of the injection oil cylinder; a1 is a first electromagnetic valve; a2 is a second electromagnetic valve; a3 is a third electromagnetic valve; a4 is a fourth electromagnetic valve; a5 is a servo valve before the hammer; h0 and H1 are both check valves; x is an energy accumulator; g is an injection piston rod; s is an injection piston; k is an inlet of the injection oil cylinder; f1 is a first cartridge valve; f2 is a second cartridge valve; f3 is a third cartridge valve; f4 is the fourth cartridge valve.
In FIG. 2, the small circles in the H0 and H1 icons indicate that the oil can only travel in the direction of the ball.
The invention improves the anti-interference capability of the system and solves the influence caused by the change of the speed and the pressure caused by the environment by respectively carrying out PID control on the speed and the casting pressure in the speed control stage and the pressurization control stage.
It should be noted that all directional indicators (such as upper, lower, left, right, front and rear … …) in the embodiment of the present invention are only used to explain the relative position relationship between the components, the movement situation, etc. in a specific posture (as shown in the drawing), and if the specific posture is changed, the directional indicator is changed accordingly. Moreover, descriptions of the present invention as relating to "first," "second," "a," etc. are for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicit ly indicating a number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, "a plurality" means at least two, e.g., two, three, etc., unless specifically limited otherwise. In the present invention, unless otherwise expressly stated or limited, the terms "connected," "secured," and the like are to be construed broadly, and for example, "secured" may be a fixed connection, a removable connection, or an integral part; can be mechanically or electrically connected; they may be directly connected or indirectly connected through intervening media, or they may be interconnected within two elements or in a relationship where two elements interact with each other unless otherwise specifically limited. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations. In addition, the technical solutions in the embodiments of the present invention may be combined with each other, but it must be based on the realization of those skilled in the art, and when the technical solutions are contradictory or cannot be realized, such a combination of technical solutions should not be considered to exist, and is not within the protection scope of the present invention.
Claims (10)
1. The method for controlling the extrusion speed and pressure of the extrusion casting machine in the injection process is characterized in that the opening of a pre-hammer servo valve connected with an injection piston device is controlled by acquiring the inlet pressure and the outlet pressure of the injection piston device in the extrusion casting machine so as to adjust the oil flow of an oil path, and the injection piston device comprises an injection oil cylinder inlet, an injection piston rod and an injection oil cylinder outlet which are sequentially arranged; the control method comprises the following steps:
s1: in the speed control stage, a voltage control signal corresponding to the injection speed set value is obtained through a valve speed control model, the opening of a servo valve in front of the hammer is controlled through the voltage control signal, the real-time speed of an injection piston rod is obtained in the process, PID control is carried out according to the real-time speed so as to adjust the voltage control signal in real time, and the opening of the servo valve in front of the hammer is adjusted according to the adjusted voltage control signal so that the speed of the injection piston rod reaches the injection speed set value;
s2: in the speed control process, acquiring the real-time position distance of the injection piston rod, the casting pressure of the extrusion casting machine and the real-time speed of the injection piston rod, and entering a pressurization control stage when the real-time position distance is greater than or equal to a pressurization set position distance, the casting pressure is greater than a pressure set value and the real-time speed is less than a pressure injection speed set value; the real-time position distance is the distance from an original point to the real-time position of the injection piston rod, and the original point is a position point where the injection piston rod is not injected;
s3: in the pressurization control stage, a voltage control signal corresponding to a pressure set value is obtained through a valve pressure control model, the opening of a servo valve in front of the hammer is controlled through the voltage control signal, in the process, the real-time pressure of an inlet of the injection oil cylinder and the real-time pressure of an outlet of the injection oil cylinder are obtained, PID control is carried out according to the real-time pressure to adjust the voltage control signal in real time, and the opening of the servo valve in front of the hammer is adjusted according to the adjusted voltage control signal, so that the casting pressure of the extrusion casting machine reaches the pressure set value.
2. The method for controlling the extrusion speed and pressure of a squeeze casting machine during injection according to claim 1, wherein the valve speed control model is obtained by:
setting a plurality of test voltages, controlling the opening of a servo valve in front of the hammer according to the test voltages so as to obtain the speed of each test voltage corresponding to the injection piston rod, and obtaining a valve speed control model according to the linear relation between each test voltage and the speed of the corresponding injection piston rod.
3. The method for controlling the extrusion speed and pressure of a squeeze casting machine during injection according to claim 1, wherein the valve pressure control model is obtained by:
setting a plurality of test voltages, acquiring a voltage build-up slope through the test voltages and the corresponding voltage build-up time, and acquiring a valve pressure control model according to a linear relation between the voltage build-up slope and the test voltages.
4. The method for controlling the extrusion speed and pressure of the squeeze casting machine during the injection process according to claim 3, wherein the injection piston device further comprises a hammer connected to the injection piston rod, and an injection piston disposed at a position where the injection cylinder inlet is toward the hammer and the injection cylinder outlet is toward the hammer, and in step S2, the casting pressure of the squeeze casting machine is obtained according to the formula:
in the formula, the pressure of an inlet of an injection oil cylinder is obtained through a pressure sensor connected with the inlet of the injection oil cylinder; the pressure of the outlet of the injection oil cylinder is obtained through a pressure sensor connected with the outlet of the injection oil cylinder.
5. The method for controlling the extrusion speed and pressure of a squeeze casting machine during injection as defined in claim 4, wherein the real-time speed and the real-time position distance of the injection piston rod are obtained by a displacement sensor provided on the injection piston rod.
6. A control system for the extrusion speed and pressure of a squeeze casting machine during injection, comprising:
the injection piston device comprises an injection oil cylinder inlet, an injection piston rod and an injection oil cylinder outlet which are arranged in sequence; pressure sensors are arranged at the inlet and the outlet of the injection oil cylinder and are used for acquiring the real-time pressure of the inlet and the outlet of the injection oil cylinder; the injection piston rod is provided with a displacement sensor for acquiring the real-time speed and the real-time position distance of the injection piston rod; the real-time position distance is the distance from an original point to the real-time position of the injection piston rod, and the original point is a position point where the injection piston rod is not injected;
a system oil supply port;
the pre-hammer servo valve is arranged between the oil supply port of the system and the inlet of the injection oil cylinder;
a control module, comprising:
the speed control unit is used for acquiring a voltage control signal corresponding to the injection speed set value through the valve speed control model in a speed control stage, controlling the opening of the pre-hammer servo valve through the voltage control signal, performing PID control according to the real-time speed of the injection piston rod in the process to adjust the voltage control signal in real time, and adjusting the opening of the pre-hammer servo valve according to the adjusted voltage control signal to enable the speed of the injection piston rod to reach the injection speed set value;
the judging unit is used for entering a pressurization control stage when the real-time position distance of the injection piston rod is greater than or equal to a pressurization set position distance, the casting pressure of the extrusion casting machine is greater than a pressure set value, and the real-time speed of the injection piston rod is less than an injection speed set value in the speed control process;
and the pressure control unit acquires a voltage control signal corresponding to the pressure set value through the valve pressure control model in the pressurization control stage, controls the opening of the pre-hammer servo valve through the voltage control signal, performs PID (proportion integration differentiation) control according to the real-time pressure of the inlet and the outlet of the injection oil cylinder in the process to adjust the voltage control signal in real time, and adjusts the opening of the pre-hammer servo valve according to the adjusted voltage control signal so as to enable the casting pressure of the extrusion casting machine to reach the pressure set value.
7. The system for controlling the extrusion speed and pressure of the squeeze casting machine during the injection process according to claim 6, wherein the injection piston device further comprises a hammer connected with the injection piston rod, and an injection piston arranged at a position from an inlet of the injection cylinder to the direction of the hammer and from an outlet of the injection cylinder to the direction of the hammer, and the casting pressure of the squeeze casting machine is obtained according to the following formula:
8. the system for controlling the extrusion speed and pressure of a extrusion caster during an injection as set forth in claim 6, further comprising:
an oil tank;
the third valve part and the fourth valve part are connected with the outlet of the injection oil cylinder in parallel;
the third valve part comprises a third electromagnetic valve, a third cartridge valve and a one-way valve; the control module is also used for opening the third cartridge valve through a third electromagnetic valve after injection so as to enable the injection piston rod to move downwards, namely return to the hammer;
the fourth valve component comprises a fourth solenoid valve and a fourth cartridge valve; and the control module is also used for opening the fourth cartridge valve through the fourth electromagnetic valve during speed control and pressurization control so as to enable oil in the outlet of the injection oil cylinder to flow back to the oil tank.
9. The system for controlling the extrusion speed and pressure of a extrusion caster during an injection as set forth in claim 8, further comprising:
the second valve component is simultaneously connected with the pre-hammer servo valve and the injection cylinder inlet and comprises a second electromagnetic valve and a second cartridge valve; the control module is also used for opening the second cartridge valve through the second electromagnetic valve after hammering, namely injection, so that oil in the inlet of the injection oil cylinder flows back to the oil tank.
10. The system for controlling the extrusion speed and pressure of a extrusion caster during an injection as set forth in claim 9, further comprising:
the first valve component is connected between a system oil supply port and the pre-hammer servo valve and comprises a first electromagnetic valve, a first cartridge valve and a one-way valve, and the one-way valve is arranged between the pre-hammer servo valve and the first cartridge valve; the control module is also used for opening the first cartridge valve through the first electromagnetic valve during speed control and pressurization control so as to lead oil of the system oil supply port to the injection piston device.
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Citations (14)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0639516A (en) * | 1992-07-24 | 1994-02-15 | Toshiba Mach Co Ltd | Method for controlling injection of die casting machine and device therefor |
| JPH0716722A (en) * | 1993-07-06 | 1995-01-20 | Ube Ind Ltd | Injection device in die casting machine |
| JPH07167109A (en) * | 1993-10-20 | 1995-07-04 | Kobe Steel Ltd | Hydraulic control valve and hydraulic cylinder circuit |
| JPH0911302A (en) * | 1995-07-04 | 1997-01-14 | Toyo Mach & Metal Co Ltd | Injection controller of injection molding machine |
| US5662159A (en) * | 1995-03-27 | 1997-09-02 | Toshiba Kikai Kabushiki Kaisha | Method and apparatus of controlling injection of die casting machine |
| JP2001001126A (en) * | 1999-06-23 | 2001-01-09 | Toshiba Mach Co Ltd | Electric injection die casting machine |
| CN1460586A (en) * | 2002-05-16 | 2003-12-10 | 住友重机械工业株式会社 | Injection moulding machine control system and control method |
| JP2004160484A (en) * | 2002-11-12 | 2004-06-10 | Toshiba Mach Co Ltd | Injection apparatus for die casting machine |
| CN1572392A (en) * | 2003-05-09 | 2005-02-02 | 东芝机械株式会社 | Injection system and casting method of die casting machine |
| JP2011131225A (en) * | 2009-12-24 | 2011-07-07 | Ube Machinery Corporation Ltd | Injection device and injection controlling method of die casting machine |
| CN103203852A (en) * | 2012-01-11 | 2013-07-17 | 博创机械股份有限公司 | Servo-valve-controlled injection oil path system of large-scale injection molding machine |
| CN106424652A (en) * | 2016-11-14 | 2017-02-22 | 苏州慧驰轻合金精密成型科技有限公司 | Pressure control system and control method of middle-high-pressure casting equipment |
| JP2018176192A (en) * | 2017-04-07 | 2018-11-15 | 東洋機械金属株式会社 | Die-casting machine |
| CN110918937A (en) * | 2019-11-07 | 2020-03-27 | 宁波力劲科技有限公司 | Hydraulic control system for injection speed of die casting machine and control method thereof |
-
2022
- 2022-05-06 CN CN202210483688.8A patent/CN114570909B/en active Active
Patent Citations (14)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0639516A (en) * | 1992-07-24 | 1994-02-15 | Toshiba Mach Co Ltd | Method for controlling injection of die casting machine and device therefor |
| JPH0716722A (en) * | 1993-07-06 | 1995-01-20 | Ube Ind Ltd | Injection device in die casting machine |
| JPH07167109A (en) * | 1993-10-20 | 1995-07-04 | Kobe Steel Ltd | Hydraulic control valve and hydraulic cylinder circuit |
| US5662159A (en) * | 1995-03-27 | 1997-09-02 | Toshiba Kikai Kabushiki Kaisha | Method and apparatus of controlling injection of die casting machine |
| JPH0911302A (en) * | 1995-07-04 | 1997-01-14 | Toyo Mach & Metal Co Ltd | Injection controller of injection molding machine |
| JP2001001126A (en) * | 1999-06-23 | 2001-01-09 | Toshiba Mach Co Ltd | Electric injection die casting machine |
| CN1460586A (en) * | 2002-05-16 | 2003-12-10 | 住友重机械工业株式会社 | Injection moulding machine control system and control method |
| JP2004160484A (en) * | 2002-11-12 | 2004-06-10 | Toshiba Mach Co Ltd | Injection apparatus for die casting machine |
| CN1572392A (en) * | 2003-05-09 | 2005-02-02 | 东芝机械株式会社 | Injection system and casting method of die casting machine |
| JP2011131225A (en) * | 2009-12-24 | 2011-07-07 | Ube Machinery Corporation Ltd | Injection device and injection controlling method of die casting machine |
| CN103203852A (en) * | 2012-01-11 | 2013-07-17 | 博创机械股份有限公司 | Servo-valve-controlled injection oil path system of large-scale injection molding machine |
| CN106424652A (en) * | 2016-11-14 | 2017-02-22 | 苏州慧驰轻合金精密成型科技有限公司 | Pressure control system and control method of middle-high-pressure casting equipment |
| JP2018176192A (en) * | 2017-04-07 | 2018-11-15 | 東洋機械金属株式会社 | Die-casting machine |
| CN110918937A (en) * | 2019-11-07 | 2020-03-27 | 宁波力劲科技有限公司 | Hydraulic control system for injection speed of die casting machine and control method thereof |
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| CN114570909B (en) | 2023-03-21 |
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