Gas-liquid linkage lower ejection device and control method

Abstract

The gas-liquid linkage lower ejection device comprises a cylinder base fixed to a machine body and a lower ejection shaft rotationally connected to the machine body, an air cylinder and a hydraulic cylinder are arranged in the cylinder base in series, a cylinder shaft sleeve is installed in the cylinder base, trunnions are arranged on the two sides of the air cylinder, and the trunnions are rotationally connected with the cylinder shaft sleeve. The lower end of a piston rod of the hydraulic cylinder is inserted above a piston of the air cylinder, a displacement sensor is installed at the upper end of the piston rod of the hydraulic cylinder, the lower end of the piston rod of the air cylinder is connected with a cylinder connector, and the cylinder connector is rotationally connected with a rocker arm which is fixedly connected with a lower ejecting shaft. The ejection stroke of an original hydraulic cylinder is shortened, especially for the hydraulic cylinder with the maintaining function, the workpiece is separated from the mold through ejection of the hydraulic cylinder, the subsequent ejection stroke and the workpiece maintaining action are independently completed by the lower air cylinder, the ejection stroke requirement is met, meanwhile, the stroke of the hydraulic cylinder is shortened, a hydraulic station system is reduced, and the cost is reduced. And the response speed is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of presses, and particularly relates to a gas-liquid linkage lower ejection device and a control method for a hot die forging press. Background Art

[0002] The hot die forging lower ejection device is a key auxiliary device in the hot die forging process, mainly used for quickly and stably taking out workpieces from the mold after forging and forming, ensuring production efficiency and product quality.

[0003] In the prior art, the hot die forging lower ejection device generally adopts hydraulic drive. Its disadvantage is that when the lower ejection force requirement is large, especially when the lower ejection needs to have a holding function, the stroke design of the hydraulic cylinder is also large, resulting in a large part of the hydraulic pump station system, and a large internal space in the foundation is required for installation and maintenance, thus increasing the equipment manufacturing cost and the foundation civil engineering cost. Summary of the Invention

[0004] The purpose of the present invention is to provide a gas-liquid linkage lower ejection device and a control method to solve the problems existing in the prior art, realize a relatively small hydraulic station system, a relatively small internal space in the foundation required for installation and maintenance, and meet the user's requirements for the use of the machine tool ejection.

[0005] The purpose of the present invention is achieved as follows: A gas-liquid linkage lower ejection device includes a cylinder seat fixed on the machine body and a lower blanking shaft rotatably connected to the machine body. A cylinder and a hydraulic cylinder are connected in series in the cylinder seat. A cylinder bushing is installed in the cylinder seat. There are trunnions on both sides of the cylinder, and the trunnions are rotatably connected to the cylinder bushing. The lower end of the piston rod of the hydraulic cylinder is inserted above the piston of the cylinder. A displacement sensor is installed at the upper end of the piston rod of the hydraulic cylinder. The lower end of the piston rod of the cylinder is connected to a cylinder joint, and the cylinder joint is rotatably connected to a rocker arm, and the rocker arm is fixedly connected to the lower blanking shaft.

[0006] For the gas-liquid linkage lower ejection device of the present invention, the stroke of the original hydraulic cylinder with a holding function is shortened, especially for the hydraulic cylinder with a holding function. The hydraulic cylinder ejects to separate the workpiece from the mold. A cylinder is arranged below the hydraulic cylinder and is made into a series linkage form with the hydraulic cylinder. After the hydraulic cylinder ejects to separate the workpiece from the mold, the required stroke and the workpiece holding action stroke are completed separately by the cylinder below. Therefore, under the condition of the same ejection stroke, the present invention reduces the stroke of the hydraulic cylinder, effectively reduces the hydraulic station system and improves the response speed, reduces the installation and maintenance space, thereby realizing the stable and safe continuous operation of the equipment, greatly improving the production efficiency and reducing the cost.

[0007] As a further improvement of the present invention, the upper end of the cylinder joint is threadedly connected to the piston rod of the cylinder. The lower end of the cylinder joint is inserted into the upper end of the rocker arm and is rotatably connected to the rocker arm pin through a rocker arm pin shaft sleeve. Both ends of the rocker arm pin are fixedly connected to the upper end of the rocker arm. The lower end of the rocker arm is sleeved on the lower ejector shaft and is connected by a key and fixed by a lower ejector shaft end cover. The connection method is simple and reliable.

[0008] As a further improvement of the present invention, a spherical contact piston rod top plate is provided on the contact surface between the piston of the cylinder and the piston rod of the hydraulic cylinder. The piston rod of the hydraulic cylinder and the piston rod top plate adopt spherical contact, and the piston rod top plate is heat-treated to improve surface wear resistance, reducing the risk of damage to the cylinder piston caused by the instantaneous action of the hydraulic cylinder.

[0009] As a further improvement of the present invention, both the cylinder and the hydraulic cylinder are double-acting cylinders, which can achieve efficient and flexible control and high reliability.

[0010] As a further improvement of the present invention, the cylinder is connected to a pneumatic control system, and the hydraulic cylinder is connected to a hydraulic control system to achieve precise linkage control of the cylinder and the hydraulic cylinder.

[0011] As a further improvement of the present invention, after the hydraulic control system controls the hydraulic cylinder to eject the workpiece and disconnect it from the mold, it returns. The pneumatic control system controls the cylinder to push the workpiece to the required high position and complete the workpiece holding function before returning. While meeting the large-stroke requirement, the workpiece has a holding action; thus, the hydraulic station system is reduced, and the installation and maintenance space are decreased; and the use requirements of the machine tool for ejection are met.

[0012] As a further improvement of the present invention, the hydraulic control system includes port A1 and port B1. The hydraulic control system includes two three-position four-way valves for controlling the oil inlet at port A1 and the oil return at port B1 or the oil inlet at port B1 and the oil return at port A1. A one-way throttle valve, an exhaust joint, a pressure gauge, and a pressure cartridge valve are provided on the pipeline between the three-position four-way valve and the hydraulic cylinder. A two-position two-way cartridge valve and a two-position three-way solenoid valve for controlling the action of the two-position two-way cartridge valve are provided between the three-position four-way valve, the accumulator, and the main oil inlet pipeline. A pressure switch is provided between the accumulator and the two-position two-way cartridge valve. A relief valve is provided between the accumulator, the main oil inlet pipeline, and the pressure cartridge valve. By providing a pressure gauge, the working pressure can be checked at any time. The exhaust joint is used to discharge the air in the hydraulic oil. The pressure switch feeds back the pressure signal to the control system. The motor on the main oil inlet pipeline drives the pump to work and provides hydraulic oil for the system. The solenoid valve and the relief valve on the main oil inlet pipeline can set the system pressure. When the oil pressure exceeds the system-set pressure, the pressure is relieved and the oil returns to the fuel tank. A hydraulic check valve is installed on the main oil inlet pipeline to ensure the flow direction of the hydraulic oil. When ejection is not required, the two-position two-way cartridge valve does not act, and the hydraulic oil cannot flow through the two-position two-way cartridge valve to the oil cylinder. When ejection is required, the control system controls the two-position three-way solenoid valve to be energized, causing the two-position two-way cartridge valve to act. The accumulator quickly discharges the hydraulic oil through the outlet of the two-position two-way cartridge valve. The two three-position four-way solenoid valves installed behind the two-position two-way cartridge valve control the flow direction of the hydraulic oil to achieve oil inlet at port A1 and oil outlet at port B1. The oil flow rate and flow velocity are adjusted by the one-way throttle valve installed at the outlet of the three-position four-way solenoid valve to ensure the sensitive and reliable operation of the oil cylinder. The relief valve plays a role in safety protection. When the set pressure is exceeded, the oil in the accumulator is depressurized and the hydraulic oil flows to the fuel tank.

[0013] As a further improvement of the present invention, the cylinder includes port A and port B. The pneumatic control system includes a two-position five-way solenoid valve for controlling the air inlet at port A and the air exhaust at port B or the air inlet at port B and the air exhaust at port A. A first pneumatic ball valve, an air filter, a first pressure gauge, a first oil mistor, a second pneumatic ball valve, a pressure regulator, a pneumatic check valve, a pressure sensor, a cylinder air storage tank, a second oil mistor, and a two-position five-way solenoid valve are sequentially provided between the main air source and the two-position five-way solenoid valve. A second pressure gauge and a safety valve are provided on the cylinder air storage tank. In this pneumatic control system, a pressure gauge is provided to check the set air pressure. The ball valve at the main air source inlet is used to turn on and off the main air source. The air filter can remove impurities such as oil, water, and foreign objects in the air. The oil mistor can atomize the lubricating oil and inject it into the air stream to lubricate the parts that need lubrication. The pressure regulator sets the inlet air pressure. The check valve controls the air flow direction. The safety valve plays a role in pressure relief protection when the instantaneous air pressure in the air storage tank is too high. The pressure sensor feeds back the pressure signal to the system to control the air pressure in the air storage tank. The two-position five-way solenoid valve can control the air inlet at port A and the air exhaust at port B or the air inlet at port B and the air exhaust at port A.

[0014] As a further improvement of the present invention, during the ejection operation, the hydraulic control system first controls the hydraulic cylinder to push the cylinder piston, and at the same time, the air circuit control system controls the cylinder and the hydraulic cylinder to move in the same direction, so that the cylinder linkage provides a large ejection force, pushing the cylinder joint to move downward, so that the rocker arm drives the lower ejection shaft to eject the material upward, so that after the workpiece is disengaged from the mold, the hydraulic cylinder no longer moves downward and the hydraulic control system controls the hydraulic cylinder piston to return to the initial position. At the same time, the air circuit control system controls the cylinder to continue to move downward, pushing the workpiece to the required height position and maintaining it, and the cylinder returns to the initial position after the workpiece is clamped.

[0015] The gas-liquid linkage lower ejection device and control method of the present invention have the following beneficial effects: 1. The pneumatic and hydraulic linkage control form is adopted so that after the hydraulic cylinder disengages the ejected workpiece from the mold, the subsequent stroke and workpiece holding stroke are completed by the cylinder.

[0016] 2. Reducing the ejection stroke of the hydraulic cylinder can achieve quick response; the ejection force can be increased without increasing the cylinder diameter by increasing the force arm from the hydraulic cylinder to the rotation center.

[0017] 3. Effectively reduce the hydraulic station system and the space inside the foundation required for installation and maintenance.

[0018] In summary, under the condition of the same ejection stroke, the present invention reduces the stroke of the hydraulic cylinder, effectively reduces the hydraulic station system and improves the response speed, reduces the installation and maintenance space, thereby realizing stable, safe and continuous operation of the equipment, greatly improving production efficiency and reducing costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic structural diagram of the gas-liquid linkage lower ejection device of the present invention.

[0020] Figure 2 for Figure 1 Cross-section along AA.

[0021] Figure 3 The figure is a schematic diagram of the hydraulic control principle of the gas-liquid linkage lower ejection device of the present invention.

[0022] Figure 4 The figure is a schematic diagram of the gas circuit control principle of the gas-liquid linkage lower ejection device of the present invention.

[0023] Among them, 1 cylinder seat; 2 displacement sensor; 3 hydraulic cylinder; 4 cylinder sleeve; 5 piston rod top plate; 6 cylinder; 7 cylinder joint; 8 rocker arm pin; 9 rocker arm pin sleeve; 10 rocker arm; 11 lower ejector shaft end cover; 12 key; 13 lower ejector shaft; 14 lower ejector bearing seat 1; 15 bearing 1; 16 bearing 2; 17 lower ejector bearing seat 2. Detailed implementation mode

[0024] As Figure 1-2 The gas-liquid linkage lower ejection device shown in the figure includes a cylinder seat 1 fixed on the machine body and a lower blanking shaft 13 rotatably connected to the machine body. A cylinder 6 and a hydraulic cylinder 3 are connected in series in the cylinder seat 1.

[0025] Specifically, a cylinder bushing 4 is installed in the cylinder seat 1. Ears are provided on both sides of the cylinder 6, and the ears are connected to the cylinder bushing 4 and can swing freely. The lower end of the piston rod of the hydraulic cylinder 3 is inserted above the piston of the cylinder 6, and a piston rod top plate 5 is detachably arranged on the contact surface between the piston of the cylinder 6 and the piston rod of the hydraulic cylinder 3. By adding a heat-treated piston rod top plate 5 at the contact part between the piston of the cylinder 6 and the piston rod of the hydraulic cylinder 3, the risk of damage to the piston of the cylinder 6 caused by the instantaneous action of the hydraulic cylinder 3 can be reduced. The upper end of the piston rod of the hydraulic cylinder 3 is installed with a displacement sensor 2, so that the ejection stroke of the hydraulic cylinder 3 can be adjusted and set through the displacement sensor 2 and the control system.

[0026] The lower end of the piston rod of the cylinder 6 is connected to a cylinder joint 7, the cylinder joint 7 is rotatably connected to a rocker arm 10, and the rocker arm 10 is fixedly connected to the lower blanking shaft 13. Specifically, the upper end of the cylinder joint 7 is threadedly connected to the piston rod of the cylinder 6, the lower end of the cylinder joint 7 is inserted into the upper end of the rocker arm 10 and is rotatably connected to a rocker arm pin 8 through a rocker arm pin bushing 9, and the rocker arm pin bushing 9 is installed in the cylinder joint 7. Both ends of the rocker arm pin 8 are fixedly connected to the upper end of the rocker arm 10. The lower end of the rocker arm 10 is sleeved on the lower blanking shaft 13 and connected by a key 12, and then fixed by a lower blanking shaft end cover 11.

[0027] A lower ejection bearing seat 14 and a lower ejection bearing seat 17 are installed on the machine body. A bearing 15 and a bearing 16 are installed in the lower ejection bearing seat 14, and a bearing 16 is installed in the lower ejection bearing seat 17. The lower blanking shaft 13 is hinged in the bearings 15 and 16 and can swing freely.

[0028] Both the cylinder 6 and the hydraulic cylinder 3 are double-acting cylinders, which can achieve efficient and flexible control and high reliability. Among them, the cylinder 6 is connected with a gas circuit control system, and the hydraulic cylinder 3 is connected with a hydraulic control system to realize the precise linkage control of the cylinder 6 and the hydraulic cylinder 3.

[0029] The specific control method of the gas-liquid linkage lower ejection device of this embodiment is as follows: when working, the hydraulic system first controls the hydraulic cylinder 3 to move by pushing the piston rod top plate 5, and at the same time, the gas circuit control system controls the cylinder 6 to move in the same direction as the hydraulic cylinder 3 so that the cylinder 6 provides a large ejection force to push the cylinder joint 7 downward so that the rocker arm 10 drives the lower ejection shaft 13 to eject upward so that the workpiece is separated from the mold, and the hydraulic cylinder 3 no longer moves downward and is controlled by the hydraulic control system to return the piston of the hydraulic cylinder 3 to the initial position. At the same time, the gas circuit system controls the cylinder 6 to continue to move downward to push the workpiece to the required height position and keep the cylinder 6 to return to the initial position after the workpiece is clamped. In this way, the stroke of the hydraulic cylinder 3 is shortened so that the workpiece can be separated from the mold, and the required stroke and workpiece holding action can be completed by the lower cylinder 6; and the ejection stroke of the hydraulic cylinder 3 can be adjusted and set by the displacement sensor 2. Therefore, when the hydraulic cylinder 3 provides the ejection force, it only needs to ensure that the workpiece is separated from the mold, thereby greatly reducing the stroke of the hydraulic cylinder 3 and making the workpiece have the function of holding action; and the hydraulic station system is reduced, reducing the installation and maintenance space; and meeting the requirements for machine tool ejection.

[0030] To meet control requirements, such as Figure 2 , Figure 3 As shown, the hydraulic control system includes A1 port and B1 port. The hydraulic control system includes two three-position four-way valves for controlling the oil inlet of A1 port and the oil return of B1 port or the oil inlet of B1 port and the oil return of A1 port. A one-way throttle valve, an exhaust joint, a pressure gauge and a pressure cartridge valve are arranged on the pipeline between the three-position four-way valve and the hydraulic cylinder 3. A two-position two-way cartridge valve and a two-position three-way solenoid valve for controlling the action of the two-position two-way cartridge valve are arranged between the three-position four-way valve and the accumulator and the main oil inlet pipeline. A pressure switch is arranged between the accumulator and the two-position two-way cartridge valve. A relief valve is arranged between the accumulator, the main oil inlet pipeline and the pressure cartridge valve. By setting a pressure gauge, the working pressure can be checked at any time. The exhaust joint is used to exhaust the air in the hydraulic oil. The pressure switch feeds back the pressure signal to the control system. The motor on the main oil inlet pipeline drives the pump to work and provide hydraulic oil to the system. The solenoid valve and the overflow valve on the main oil inlet pipeline can set the system pressure. When the oil pressure exceeds the pressure set by the system, the pressure is relieved back to the oil tank. A hydraulic one-way valve is installed on the main oil inlet pipeline to ensure the flow direction of the hydraulic oil. When ejection is not required, the two-position two-way cartridge valve does not work, and the hydraulic oil cannot flow to the cylinder through the two-position two-way cartridge valve. When ejection is required, the control system controls the two-position three-way solenoid valve to be energized, so that the two-position two-way cartridge valve is activated, and the accumulator quickly flows the hydraulic oil out through the outlet of the two-position two-way cartridge valve. The two three-position four-way solenoid valves installed behind the two-position two-way cartridge valve control the flow direction of the hydraulic oil, so that the oil enters the A1 port and the oil exits the B1 port; the one-way throttle valve installed at the outlet of the three-position four-way solenoid valve is used to adjust the oil flow and flow rate to ensure the sensitive and reliable action of the cylinder. The overflow valve plays a role in safety protection. When the set pressure is exceeded, the oil in the accumulator is depressurized and the hydraulic oil flows to the oil tank.

[0031] like Figure 2 , Figure 4 As shown, the cylinder 6 includes a port A and a port B, and the air circuit control system includes a two-position five-way solenoid valve for controlling air intake at port A and exhaust at port B or air intake at port B and exhaust at port A. A first air circuit ball valve, an air filter, a first pressure gauge, a first oil mist collector, a second air circuit ball valve, a pressure regulating valve, a pneumatic one-way valve, a pressure sensor, a cylinder 6 air reservoir, a second oil mist collector and a two-position five-way solenoid valve are arranged in sequence between the main air source and the two-position five-way solenoid valve, and a second pressure gauge and a safety valve are arranged on the cylinder 6 air reservoir. In this air circuit control system, a pressure gauge is provided to check the set air pressure. The ball valve at the main air source inlet is used to open and close the main air source. The air filter can remove impurities such as oil, water, and foreign matter in the air. The oil mist collector can atomize the lubricating oil and inject it into the air flow to lubricate the parts that need lubrication. The pressure regulating valve sets the intake pressure, the one-way valve controls the air flow direction, and the safety valve plays a pressure relief protection role when the air pressure in the air tank is too high. The pressure sensor feeds back the pressure signal to the system to control the air pressure in the air tank. The two-position five-way solenoid valve can control the intake at port A and the exhaust at port B, or the intake at port B and the exhaust at port A.

[0032] The above hydraulic control system and air circuit control system specifically control the action sequence: during the initial ejection, the hydraulic system controls the oil inlet at port A1 and the oil return at port B1, the piston rod of the hydraulic cylinder 3 quickly pushes the piston rod top plate 5, and at the same time, the air circuit control system controls the air inlet at port A and the exhaust at port B, so that the cylinder 6 provides a large ejection force to push the cylinder joint 7 downward, so that the rocker arm 10 drives the lower ejection shaft 13 to eject upward, so that the workpiece is separated from the mold, and the hydraulic cylinder 3 no longer moves downward and the hydraulic system controls the oil inlet at port B1 and the oil return at port A1 to return the hydraulic cylinder 3 to the initial position. At the same time, the air circuit system controls the cylinder 6 to continue to move downward to push the workpiece to the required height position and keep it until the workpiece is clamped. The air circuit system controls the air inlet at port B and the exhaust at port A, and the cylinder 6 returns to the initial position. According to the needs of different molds, the stroke of the workpiece and the mold separation can be adjusted by the hydraulic cylinder sensor.

[0033] The present invention is not limited to the above-mentioned embodiments. On the basis of the technical solution disclosed in the present invention, technicians in this field can make some substitutions and deformations to some technical features therein according to the disclosed technical content without creative labor, and these substitutions and deformations are all within the protection scope of the present invention.

Claims

1. A gas-liquid linkage lower ejection device, comprising a cylinder seat fixed on a machine body and a lower ejection shaft rotatably connected to the machine body, characterized in that: An air cylinder and a hydraulic cylinder are arranged in series in the cylinder base, a cylinder sleeve is installed in the cylinder base, ear shafts are provided on both sides of the cylinder, the ear shafts are rotatably connected to the cylinder sleeve, the lower end of the piston rod of the hydraulic cylinder is inserted above the piston of the cylinder, a displacement sensor is installed on the upper end of the piston rod of the hydraulic cylinder, the lower end of the piston rod of the cylinder is connected to the cylinder joint, the cylinder joint is rotatably connected to the rocker arm, and the rocker arm is fixedly connected to the lower ejector shaft.

2. The gas-liquid linkage lower ejection device according to claim 1 is characterized in that: The upper end of the cylinder joint is threadedly connected to the piston rod of the cylinder, the lower end of the cylinder joint is inserted into the upper end of the rocker arm and is rotatably connected to the rocker pin through a rocker pin sleeve, the two ends of the rocker pin are fixedly connected to the upper end of the rocker arm, the lower end of the rocker arm is sleeved on the lower ejector shaft and is connected by a key and fixed by the end cover of the lower ejector shaft.

3. The gas-liquid linkage lower ejection device according to claim 1 is characterized in that: A spherical surface is provided on the contact surface between the piston of the air cylinder and the piston rod of the hydraulic cylinder to contact the piston rod top plate.

4. The gas-liquid linkage lower ejection device according to claim 1, characterized in that: The air cylinder and the hydraulic cylinder are both double-acting cylinders.

5. The gas-liquid linkage lower ejection device according to claim 1 is characterized in that: The air cylinder is connected to an air circuit control system, and the hydraulic cylinder is connected to a hydraulic control system.

6. The gas-liquid linkage lower ejection device according to claim 5, characterized in that: The hydraulic control system controls the hydraulic cylinder to push the workpiece out of the mold and then return, and the air circuit control system controls the cylinder to push the workpiece to the required high position and complete the workpiece holding function before returning.

7. The gas-liquid linkage lower ejection device according to claim 5, characterized in that: The hydraulic control system includes an A1 port and a B1 port, and includes two three-position four-way valves for controlling oil inlet at A1 port and oil return at B1 port or oil inlet at B1 port and oil return at A1 port. A one-way throttle valve, an exhaust joint, a pressure gauge and a pressure cartridge valve are provided on the pipeline between the three-position four-way valve and the hydraulic cylinder. A two-position two-way cartridge valve and a two-position three-way solenoid valve for controlling the action of the two-position two-way cartridge valve are provided between the three-position four-way valve and the accumulator and the main oil inlet pipeline. A pressure switch is provided between the accumulator and the two-position two-way cartridge valve, and an overflow valve is provided between the accumulator, the main oil inlet pipeline and the pressure cartridge valve.

8. The gas-liquid linkage lower ejection device according to claim 5, characterized in that: The cylinder includes port A and port B, and the air circuit control system includes a two-position five-way solenoid valve for controlling air intake at port A and exhaust at port B or air intake at port B and exhaust at port A. A first air circuit ball valve, an air filter, a first pressure gauge, a first oil mist collector, a second air circuit ball valve, a pressure regulating valve, a pneumatic one-way valve, a pressure sensor, a cylinder air reservoir, a second oil mist collector and a two-position five-way solenoid valve are arranged in sequence between the main air source and the two-position five-way solenoid valve, and a second pressure gauge and a safety valve are arranged on the cylinder air reservoir.

9. The control method of the gas-liquid linkage lower ejection device according to claim 4, characterized in that: During ejection, the hydraulic control system controls the hydraulic cylinder to push the cylinder piston. At the same time, the air circuit control system controls the cylinder and the hydraulic cylinder to move in the same direction, pushing the cylinder joint downward, so that the rocker arm drives the lower ejector shaft to eject the material upward. After the workpiece is disengaged from the mold, the hydraulic cylinder no longer moves downward and the hydraulic control system controls the hydraulic cylinder piston to return to the initial position. At the same time, the air circuit control system controls the cylinder to continue to move downward, pushing the workpiece to the required height position and maintaining it. After the workpiece is clamped, the cylinder returns to its initial position.

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