Metal casting system, quantitative holding furnace and quantitative supply device of holding furnace

Abstract

The utility model aims to overcome the defects of material waste and poor product quality caused by inaccurate quantitative supply of molten metal due to the adoption of a method and a structure for supplying compressed gas into a furnace body and quantitatively outputting the molten metal by virtue of the pressure of the compressed gas in the prior art. The utility model provides a metal casting system, a quantitative heat preservation furnace and a heat preservation furnace quantitative supply device, the heat preservation furnace quantitative supply device comprises a quantitative piston, a quantitative piston cylinder, a quantitative pressurization control system and a quantitative and pressurization driving device, and the quantitative heat preservation furnace comprises a molten metal holding device, a heat preservation furnace quantitative supply device and a molten metal liquid lifting device. The metal casting system comprises the casting machine and the quantitative holding furnace, and by adopting the metal casting system, the quantitative holding furnace and the quantitative supply device of the holding furnace, accurate quantitative supply can be obtained, unstable product quality caused by unstable supply quantity is reduced, and raw materials can be effectively saved.

Description

TECHNICAL FIELD

[0001] The utility model belongs to molten metal transfer equipment technical field, especially relate to metal casting system, quantitative heat preservation furnace and heat preservation furnace quantitative feeding device. BACKGROUND

[0002] The heat preservation furnace is a container for storing molten metal and keeping the molten metal at a certain temperature or appropriately increasing the temperature of the molten metal. When the molten metal in the furnace body is used, the molten metal needs to be taken out from the furnace body according to the required amount and sent to the device that needs the molten metal. At present, the quantitative transfer of molten metal is mostly carried out by using a pressure quantitative feeding device to quantitatively transport the molten metal liquid. The gas pressure type quantitative furnace of Shijieke Xi widely used in the market also adopts the pressure quantitative feeding mode and structure. For example, the Chinese utility model patent with the patent publication number CN219283942U, the name of which is a gas pressure quantitative heat preservation furnace, comprises a furnace box main body 1, a liquid outlet mechanism 2 is fixedly arranged on one side of the upper end face of the furnace box main body 1, a liquid inlet mechanism 3 is fixedly connected to the side of the upper end face of the furnace box main body 1 away from the liquid outlet mechanism 2, a gas pressure control mechanism 4 is fixedly arranged on one side of the furnace box main body 1, a main machine control system 5 is fixedly arranged on the front of the furnace box main body 1, a heat preservation box 6 is fixedly arranged in the furnace box main body 1, the heat preservation box 6 can maintain the temperature of the liquid, and the design of the electric heating device 7 fixedly arranged in the heat preservation box 6 can ensure the process temperature of the aluminum liquid. During work, the molten aluminum liquid is added through the liquid inlet mechanism 3 from the water transfer package, and the aluminum liquid in the quantitative heat preservation furnace is heated and kept warm by the electric heating device 7; the liquid outlet is controlled by the liquid outlet mechanism 2, the main machine control system 5 and the gas pressure control mechanism 4, when the die casting machine completes a die casting operation and transmits a signal to the heat preservation furnace control system, the main machine control system 5 controls the liquid outlet mechanism 2 to open, the gas pressure control mechanism 4 injects compressed gas into the heat preservation furnace, and the main machine control system 5 simulates calculation to realize quantitative aluminum liquid supply. The above device and method are used for quantitative supply of furnace liquid. Since the supply amount of the molten metal liquid is controlled by the size of the gas pressure and the supply pressure time when the compressed gas is injected into the heat preservation furnace, the pressure of the compressed gas supplied into the furnace body is released, so the pressure itself is unstable, which makes the height of the liquid surface controlled by the gas pressure inaccurate, the supply amount of the molten metal liquid is inaccurate, a large amount of waste is generated in the process, a large amount of compressed gas is consumed in the process, and a lot of energy is consumed. On the other hand, the injected gas can oxidize the molten metal liquid on the surface, reduce the quality of the molten metal liquid, and affect the quality of the finished product. Especially when the heat preservation furnace is used in the metal casting industry, such as high pressure, low pressure or medium pressure metal casting, the heat preservation furnace is commonly used for heat preservation and storage of molten metal, and then the molten metal is pressed into the cavity of the casting mold to complete the casting.

[0003] In addition, the prior art quantitative holding furnace adopts a two-chamber structure, and the furnace body is divided into a left chamber hearth (a pressurized chamber) and a right chamber hearth (a holding chamber). The right chamber hearth is communicated with the atmosphere, and a movable furnace cover is arranged at the top of the right chamber hearth. A conventional heating hot immersion pipe is arranged at the bottom of the right chamber hearth. A furnace door and a furnace door cover which are inclined at an angle of 45 degrees are arranged at the right end of the right chamber hearth, and are used for charging and holding. The left chamber hearth is a closed chamber, and a fixed sealing furnace cover is arranged at the top of the left chamber hearth. An immersion pipe type heater, a thermocouple and a liquid level meter are arranged at the top of the furnace cover. They are used for measuring the temperature and liquid level height of the aluminum liquid in the left chamber hearth. When the temperature of the aluminum liquid in the left chamber hearth is lower than the set pouring stability, the heater is turned on to heat the aluminum liquid in the left chamber hearth. An inclined pouring cup pouring nozzle sleeve is arranged at the left end of the left chamber hearth. One end of the pouring cup pouring nozzle sleeve is immersed in the aluminum liquid, and the other end is open. The aluminum liquid flows out through the open end of the pouring cup pouring nozzle sleeve by pressurizing the left chamber. A scanning electrode is arranged above the open end of the pouring cup pouring nozzle sleeve. It is a standard for determining the standby pouring state. A valve is arranged between the left and right chamber hearths. When the valve is opened, the liquid in the right chamber enters the left chamber. When the liquid levels of the left and right chamber hearths are horizontal, the valve is closed to maintain the air tightness of the left chamber hearth. In addition, an air control device is arranged at the upper portion of the left chamber hearth. The air control device comprises an air charging valve group, a pressure sensor and an air discharging valve. Since the air control device and the scanning electrode which are used in cooperation with the air control device are arranged on the furnace body, the constant positive pressure in the furnace body can be set through the air control device and the scanning electrode. Meanwhile, the volume change amount after the pressure change in the furnace body can be calculated through the electric control device to realize the high-precision quantitative delivery of the aluminum liquid. With the above structure, when the pressure is increased, the molten metal liquid is delivered out from the pouring cup pouring nozzle sleeve. When the molten metal is quantitatively delivered and the pressure is released, the pressure in the furnace body rapidly decreases, and the molten metal delivered through the liquid delivery pipe and the molten metal in the pouring cup pouring nozzle sleeve rapidly flows back to the left chamber hearth. The molten metal and impurities which are deposited at the bottom of the furnace are all filled up, so that the molten metal is stirred, the impurities deposited at the bottom of the furnace are stirred up, the quality of the molten metal is reduced, and the quality of the product is reduced. Content of the utility model

[0004] The utility model discloses a metal casting system, quantitative holding furnace and holding furnace quantitative supply device.

[0005] The utility model discloses a metal casting system, quantitative holding furnace and holding furnace quantitative supply device.

[0006] A constant-temperature furnace quantitative supply device comprises a quantitative piston, a quantitative piston cylinder, a quantitative pressure control system and a quantitative and pressure driving device. The quantitative piston is located in the piston cylinder body and is connected with the piston cylinder body through clearance fit sliding connection. The piston cylinder body inner cavity is located below the quantitative piston and constitutes a pressure chamber. The pressure chamber is used for containing molten metal. The output end of the quantitative and pressure driving device is located in the piston cylinder body. The upper surface of the quantitative piston is fixedly connected with the output end of the quantitative and pressure driving device. The quantitative and pressure control system is electrically connected with the quantitative and pressure driving device. The quantitative and pressure driving device is driven by the quantitative and pressure control system to drive the quantitative piston to move in the piston cylinder body by a set stroke, so that the molten metal is quantitatively and pressurizedly output from the pressure chamber. The molten metal is input into the pressure chamber. The quantitative and pressure driving device is a servo driving device. The quantitative and pressure control system is a servo control system.

[0007] The servo driving device is one of a servo hydraulic system, a servo electric cylinder and a servo motor. The pressure chamber is used for being in communication with a molten metal lifting device and a holding chamber arranged in the holding chamber furnace body. The holding chamber is used for containing and heat-insulating molten metal after refining. The molten metal is provided from the holding chamber to the pressure chamber. The molten metal quantitatively and pressurizedly output from the pressure chamber is output to the molten metal lifting device.

[0008] The quantitative piston and the piston cylinder inner cavity are connected through clearance fit liquid sealing activity.

[0009] A constant-temperature furnace comprises a molten metal holding device, a constant-temperature furnace quantitative supply device and a molten metal lifting device. The molten metal holding device comprises a holding chamber furnace body, a constant-temperature furnace stopper, a constant-temperature furnace stopper driving device, a holding chamber heating device and a holding chamber temperature detection device. The holding chamber furnace body is provided with a holding chamber liquid outlet which is in communication with the holding chamber inner cavity. The holding chamber furnace body is provided with a constant-temperature furnace stopper passing port through which the constant-temperature furnace stopper passes and is connected with the constant-temperature furnace stopper through sealing fit activity. The constant-temperature furnace stopper passing port is in line with the center line of the holding chamber liquid outlet. One end of the constant-temperature furnace stopper is located in the holding chamber. The other end of the constant-temperature furnace stopper is fixedly connected with the output end of the constant-temperature furnace stopper driving device. The constant-temperature furnace stopper can close or leave the holding chamber liquid outlet under the driving of the constant-temperature furnace stopper driving device. The holding chamber is used for containing and heat-insulating molten metal.

[0010] The constant-temperature furnace quantitative supply device adopts the structure of the constant-temperature furnace quantitative supply device.

[0011] The molten metal lifting device comprises a lifting furnace. A lifting chamber is arranged in the lifting furnace. The molten metal enters the mold cavity of a casting machine through the lifting chamber.

[0012] The liquid lifting chamber, the pressurizing chamber and the holding chamber are communicated with each other through the chamber communication channel, the liquid lifting chamber and the pressurizing chamber are in free communication, and the chamber communication channel is communicated with the holding chamber through the holding chamber liquid outlet;

[0013] When the quantitative and pressurized supply of the holding furnace quantitative supply device is completed, the holding furnace stopper enters into the holding chamber liquid outlet to close the holding chamber liquid outlet.

[0014] The liquid lifting chamber is in a whole cylinder shape, comprising a liquid lifting channel and a liquid lifting channel contraction part, and a liquid lifting channel liquid outlet channel is arranged at the liquid outlet end of the liquid lifting channel contraction part, and the liquid lifting channel contraction part is communicated with the liquid lifting channel liquid outlet end through the small diameter end thereof;

[0015] The holding chamber, the pressurizing chamber and the liquid lifting chamber are arranged side by side, the liquid lifting chamber is in a whole cylinder shape, and the liquid lifting channel liquid outlet end is opened upward;

[0016] The quantitative piston is driven by the quantitative and pressurized driving device to move downward from the original position of the quantitative piston by a set distance, the molten metal in the pressurizing chamber is pressurized and quantitative supply is implemented, and the quantitative and pressurized control system controls the stroke of the quantitative piston in one of the following modes: when the quantitative and pressurized supply is completed, the quantitative and pressurized driving device does not act, and the quantitative piston is kept in the original position after the mold filling and pressurizing; when the next mold filling is needed, the quantitative piston continues to move downward by a set distance in the original position after the mold filling and pressurizing, and the downward movement is repeated for multiple times until the quantitative piston returns to the original position, the holding furnace stopper is opened, the molten metal in the holding chamber flows into the pressurizing chamber and the liquid lifting chamber, and the molten metal is suspended in the liquid lifting chamber; when the next pressurizing and mold filling is needed, the quantitative piston moves downward by a set distance under the driving of the quantitative and pressurized driving device until the molten metal in the liquid lifting chamber and the pressurizing chamber needs to be supplemented after multiple mold filling and pressurizing; after the quantitative piston returns to the original position driven by the quantitative and pressurized driving device, the holding furnace stopper is opened again, the molten metal in the holding chamber flows into the pressurizing chamber, the liquid lifting chamber and the chamber communication channel again, reaches a preset height, the holding furnace stopper closes the holding chamber liquid outlet again, the quantitative and pressurized driving device drives the quantitative piston to move downward again by a set distance in sections, until the molten metal needs to be filled into the pressurizing chamber and the liquid lifting chamber again, and the quantitative and pressurized supply is repeated, and when the quantitative piston returns to the original position, the liquid level of the molten metal in the holding chamber needs to be higher than or equal to the height of the lower end surface of the quantitative piston when the quantitative piston is in the original position;

[0017] Alternatively, after each quantitative supply and pressurized mold filling is completed, the quantitative piston returns to the original position, and then moves downward from the original position, the quantitative supply and pressurized mold filling are implemented, and the holding furnace stopper makes corresponding actions, so that when the quantitative piston returns, the holding chamber and the pressurizing chamber are communicated, the molten metal enters into the pressurizing chamber and the liquid lifting chamber, and reaches the quantitative piston below and contacts with the quantitative piston; when the quantitative piston returns to the original position, the liquid level of the molten metal in the holding chamber needs to be higher than or equal to the height of the lower end surface of the quantitative piston when the quantitative piston is in the original position;

[0018] Alternatively, the quantitative and pressurizing driving device drives the quantitative piston to move downward from the original position of the quantitative piston by a set distance, to quantitatively deliver and pressurize the molten metal, and the molten metal enters the mold cavity from the riser channel into the delivery channel, and the quantitative piston remains stationary after the mold cavity is filled, and the quantitative and pressurizing driving device and the quantitative piston continuously provide pressure for the molten metal liquid, and when the molten metal in the mold cavity solidifies, the quantitative and pressurizing driving device drives the quantitative piston to partially return according to the pre-set displacement, so that the quantitative piston returns to the original position, and the molten metal is suspended in the riser chamber, waiting for the next quantitative delivery, and the quantitative and pressurizing is repeated multiple times, and each time the return is partial return, and the molten metal is kept suspended in the riser chamber, until the molten metal needs to be supplemented into the pressurizing chamber, the quantitative and pressurizing driving device drives the quantitative piston to return to the original position, and the holding furnace stopper moves accordingly, so that the holding chamber and the pressurizing chamber are communicated when or after the piston returns to the original position, so that the molten metal enters the pressurizing chamber and the riser chamber, and the quantitative and pressurizing is repeated multiple times, and each time the return is partial return, and the molten metal is kept suspended in the riser chamber, until the molten metal needs to be supplemented into the pressurizing chamber again, the quantitative and pressurizing driving device drives the quantitative piston to return to the original position, and the cycle is repeated.

[0019] The molten metal is added into the holding chamber when the liquid level of the molten metal in the holding chamber is equal to or lower than the height of the lower end surface of the quantitative piston when the quantitative piston is at the original position.

[0020] A metal casting system comprises a casting machine and a quantitative holding furnace, and the quantitative holding furnace adopts the quantitative holding furnace structure.

[0021] The casting machine is one of a low-pressure casting machine, a high-pressure casting machine, a differential pressure casting machine or an extrusion casting machine, and the riser chamber is communicated with the mold cavity of the casting machine.

[0022] The advantages and beneficial effects of the utility model are as follows:

[0023] The volume of the molten metal pushed by the quantitative piston displacement is the supply amount of the molten metal, and the supply amount is only positively correlated with the displacement amount of the quantitative piston, so the precision of the quantitative supply amount can be controlled by controlling the displacement precision of the quantitative piston, and therefore, the holding furnace quantitative supply device of the utility model is used in cooperation with the servo driving device, accurate quantitative supply can be obtained, product quality instability caused by unstable supply amount can be reduced, and raw materials can be effectively saved.

[0024] The quantitative holding furnace with the utility model embodiment structure has the following advantages:

[0025] 1. Precise quantitative feeding; 2. Will not cause molten metal to churn when the metal liquid surface falls back; 3. Adopting three-chamber structure of holding chamber, pressurizing chamber and liquid lifting chamber, so that the aluminum liquid can be uniformly heated in different chambers, reducing temperature difference and good uniformity of molten metal temperature, thereby ensuring the stability of aluminum liquid quality. 4. Improve production efficiency: Since the holding chamber is only used to contain metal liquid, when quantitative and pressurized feeding is carried out, the holding chamber is closed, therefore, the metal liquid has sufficient heating and heat preservation time in the holding chamber, and the aluminum liquid can be continuously supplied, reducing the production interruption caused by waiting for the aluminum liquid to warm up, thereby improving the overall production efficiency. 5. Reduce oxidation and slag inclusion: The holding chamber is closed when no metal liquid is added, providing a relatively stable environment, reducing the contact of aluminum liquid with air, reducing the generation of oxidation and slag inclusion, and improving the purity of aluminum liquid. 6. Easy to control and adjust: Each chamber can independently control the temperature and flow, which is convenient for flexible adjustment according to production needs. BRIEF DESCRIPTION OF DRAWINGS

[0026] Figure 1 It is the whole structure schematic view of the metal casting system embodiment of the utility model;

[0027] Figure 2 It is Figure 1 A enlarged view.

[0028] BRIEF DESCRIPTION OF DRAWINGS,

[0029] 100- molten metal holding device; 101- heat preservation furnace stopper; 102- heat preservation furnace stopper driving device; 103- holding chamber; 104- holding chamber furnace body; 105, holding chamber liquid outlet;

[0030] 200- heat preservation furnace quantitative feeding device; 201- quantitative and pressurized driving device; 202- quantitative piston; 203- quantitative piston cylinder; 204- piston cylinder body inner cavity; 205- pressurizing chamber;

[0031] 300- molten metal liquid lifting device; 301- liquid lifting channel; 302- liquid lifting channel contraction part; 303- liquid lifting channel liquid outlet channel;

[0032] 400- heating device;

[0033] 500- casting machine; 501- upper mold; 502- lower mold; 503- cavity; 504- pouring gate; 505- pouring cup pouring sleeve; 506- mold flow divider cone;

[0034] 600- chamber communication channel;

[0035] 700- molten metal. DETAILED DESCRIPTION

[0036] The present invention will be further described in detail below through specific embodiments. The following embodiments are only descriptive and not limiting, and should not be used to limit the protection scope of the present invention.

[0037] like Figure 1 As shown, the quantitative holding furnace of this embodiment includes a molten metal holding device 100, a molten metal pressurizing unit 200, and a molten metal lifting device 300. The molten metal holding device holds molten metal 700 and conveys it to the molten metal pressurizing unit. The molten metal pressurizing unit pressurizes the molten metal and quantitatively presses it into the molten metal lifting device. The molten metal lifting device then conveys the molten metal into the mold cavity of the casting machine, completing the filling process. The molten metal holding device 100, the molten metal pressurizing unit 200, and the molten metal lifting device 300 are all equipped with heating devices and temperature detection devices to monitor the temperature of the molten metal and maintain its temperature.

[0038] The molten metal holding device 100 includes a holding chamber furnace body 104, a holding furnace stopper rod 101, and a holding furnace stopper rod driving device 102. A holding chamber 103 is provided within the holding chamber furnace body, containing refined molten aluminum and other molten metal. A holding chamber outlet 105 is located at the bottom of the holding chamber furnace body, communicating with the inner cavity of the holding chamber. A holding furnace stopper rod passage is located at the top of the holding chamber furnace body, through which the holding furnace stopper rod passes and is movably connected in a sealing fit. The holding furnace stopper rod passage is collinear with the center line of the holding chamber outlet 105. One end of the holding furnace stopper rod is located inside the holding chamber, and the other end is fixedly connected to the output end of the holding furnace stopper rod driving device. Under the drive of the holding furnace stopper rod driving device, the holding furnace stopper rod can close the holding chamber outlet or leave the holding chamber outlet. A holding chamber heating device and a temperature detection device are provided inside or outside the holding chamber to ensure that the holding chamber reaches and maintains a set temperature.

[0039] The quantitative supply device 200 of the holding furnace comprises a quantitative and pressurized driving device 201, a quantitative piston 202, a quantitative piston cylinder 203, and a quantitative and pressurized control system (not shown in the figure). For the convenience of description, the inner cavity of the quantitative piston cylinder 203 is referred to as a piston cylinder body inner cavity 204, the quantitative piston is located in the piston cylinder body inner cavity, the part of the quantitative piston cylinder inner cavity below the quantitative piston constitutes a pressurized chamber 205, the pressurized chamber is used for quantitative and pressurized molten metal, the output end of the quantitative and pressurized driving device 201 is fixedly connected with the upper surface of the quantitative piston in the piston cylinder inner cavity, and the quantitative piston is in clearance fit sliding connection with the quantitative piston cylinder inner cavity. The quantitative and pressurized driving device 201 can adopt a servo driving device, such as a servo motor, a servo cylinder, a servo hydraulic cylinder, etc. The servo driving device drives the piston to reciprocate in the quantitative piston cylinder inner cavity. Since the stroke of the servo driving device can be preset in the control system, the servo driving output has high precision, the position of the quantitative piston can be accurately controlled, the control position has high precision, and the stability is good. Therefore, the stroke error of the piston in each movement is small. When the servo driving device is used as the quantitative and pressurized driving device, the quantitative and pressurized control system adopts a servo control system. The quantitative and pressurized control system is electrically connected with the quantitative and pressurized driving device. When quantitative supply is needed, the quantitative and pressurized control system controls the quantitative and pressurized driving device to move a set distance, thereby completing the quantitative supply of molten metal liquid.

[0040] The molten metal lifting device 300 comprises a lifting furnace, a lifting chamber is arranged in the lifting furnace, the lifting chamber is used for the upward movement of molten metal such as aluminum liquid, and the molten metal enters the mold cavity of the casting machine through the lifting chamber. The lifting chamber is preferably in a cylindrical structure, comprising a lifting passage 301 and a lifting passage contraction part 302, a lifting passage liquid outlet passage 303 is arranged at the liquid outlet end of the lifting passage contraction part; the lifting passage contraction part is communicated with the lifting passage liquid outlet end through the small-diameter end thereof, a chamber communication passage 600 is arranged below the holding chamber, the pressurized chamber and the lifting chamber, the lower ends of the holding chamber, the pressurized chamber and the lifting chamber are communicated through the chamber communication passage, and the lifting chamber and the pressurized chamber share one heating device to maintain the temperature of the molten metal. The caliber of the lifting passage liquid outlet passage 303 is consistent with the caliber shape and size of the connection between the lifting passage liquid outlet passage 303 and the lifting passage contraction part, and is a uniform passage. By adopting the above structure, the lifting passage contraction part is arranged, the cross-sectional area of the lifting passage and the chamber communication passage can maintain a relatively large ratio, which is beneficial to arranging an appropriate amount of molten metal liquid in the lifting chamber and the chamber communication passage, maintaining the temperature of the molten metal liquid, maintaining the uniformity of the temperature of the molten metal, and preventing the amount of the molten metal in the chamber communication passage and the lifting chamber from being too small to cause the temperature to drop too fast and the temperature to be non-uniform. The lifting chamber is in a whole cylindrical shape. In the structure of the utility model, the holding chamber, the pressurized chamber and the lifting chamber are arranged side by side, the chamber communication passage is located below the three, the three are communicated with each other through the lower ends,

[0041] The casting machine and the holding furnace constitute a metal casting system. The holding furnace can be used in combination with a low-pressure casting machine or a high-pressure casting machine. When used in combination with the high-pressure casting machine, the liquid lifting passage and the liquid outlet passage are connected with the injection cavity of the high-pressure casting machine. The holding furnace can also be used in a differential pressure casting machine or an extrusion casting machine. When used in the extrusion casting machine, the liquid lifting passage and the liquid outlet passage are connected with the pouring gate of the cavity. During the operation of the metal casting system, refined aluminum liquid or other molten metal is placed in the holding chamber, and the heating device can be arranged in the holding chamber to heat the cavity of the holding chamber. A radiation heating device can also be arranged outside the holding chamber to heat the holding chamber, so that the temperature of the molten metal in the holding chamber reaches and maintains the set temperature. The aluminum liquid or other molten metal can be heated and held by the bottom heating or radiation heating method. When the molten metal needs to enter the pressurizing chamber, the holding furnace plug rod driving device drives the holding furnace plug rod to move upward, the liquid outlet 105 of the holding chamber is opened, and the aluminum liquid or other molten metal can flow into the pressurizing chamber, the liquid lifting chamber and the cavity communication passage, so that the holding chamber, the pressurizing chamber and the liquid lifting chamber all have refined and qualified aluminum liquid or other molten metal. When the molten metal fills the pressurizing chamber, the liquid lifting chamber and the cavity communication passage, the holding furnace plug rod moves downward to close the liquid outlet of the holding chamber. The heating device 400 in the cavity communication passage 600 heats and holds the molten metal. When the molten metal needs to be filled into the casting machine, the holding furnace plug rod is kept in the closed state. When the mold needs to be filled, the quantitative piston is driven by the quantitative pressurizing driving device to move downward from the original position of the quantitative piston by a set distance, so as to pressurize and quantitatively supply the molten metal in the pressurizing chamber. During the whole process, since the cross-sectional area of the piston cylinder cavity is fixed, the volumes of the liquid lifting chamber and the cavity communication passage are also fixed. Therefore, by accurately controlling the displacement of the piston, the amount of molten metal filled into the cavity can be accurately controlled, so that the volume of the quantitatively supplied molten metal is accurate. Since the servo driving and the cam driving both have high displacement accuracy, the amount of molten metal supplied each time is relatively accurate. Moreover, during the pressurizing, the servo driving has good speed and acceleration stability, and the pressure uniformity is good, so that the filling speed is uniform.When the pressure filling is completed, the piston and the plug rod of the holding furnace move in the following ways: first, when the quantitative and pressure filling is completed, the quantitative and pressure driving device does not move, and the piston remains in the original position after the pressure filling. When the next pressure filling is needed, the piston continues to move downward by a set distance in the original position after the pressure filling, and repeats the downward movement for multiple times until the piston returns to the original position. Then, the plug rod of the holding furnace is opened, and the molten metal is filled into the pressure chamber and the liquid lifting chamber from the holding chamber, and the molten metal is suspended in the liquid lifting chamber. When the next pressure filling is needed, the piston moves downward again under the driving of the quantitative and pressure driving device until the molten metal needs to be supplemented in the liquid lifting chamber and the pressure chamber after multiple pressure fillings. After the piston returns to the original position under the driving of the quantitative and pressure driving device, the plug rod of the holding furnace is opened again, and the molten metal in the holding chamber flows into the pressure chamber, the liquid lifting chamber and the chamber communication channel again to reach the preset height. Then, the plug rod of the holding furnace is closed again, the quantitative and pressure driving device drives the piston to move downward again according to the set travel, and the quantitative and pressure filling is repeated until the molten metal needs to be filled into the pressure chamber and the liquid lifting chamber again. The conditions under which the piston returns to the original position include but are not limited to the insufficient amount of molten metal and the need to ensure that the molten metal in the pressure chamber maintains a set temperature. The advantage of this way is that the quantitative supply and the pressure filling are completed at the same time, and the piston remains in the original position after each quantitative supply and pressure filling, waiting for the next quantitative supply and pressure filling. In this way, the running efficiency of the whole system is high, and the control of the control system is simple and reliable. Since batch production is generally used in actual production, the amount of molten metal needed for the same batch of castings is certain. Therefore, the position of the piston is more accurate, the amount of quantitative supply is more accurate, and the molten metal raw material can be effectively saved.Moreover, the molten metal surface is kept stable without returning of the piston each time, which is more beneficial to the stability of liquid flow during filling, and is beneficial to the improvement of product quality. In this case, the liquid level of the molten metal in the holding chamber needs to be higher than or equal to the height of the lower end surface of the piston when the piston is at the original position. In the second case, the piston returns to the original position after each quantitative feeding and pressure filling, and then moves downward from the original position for quantitative feeding and pressure filling. Thus, the stopper of the holding furnace needs to move correspondingly to make the holding chamber and the pressure chamber communicate with each other when the piston returns, so that the molten metal enters the pressure chamber and the liquid lifting chamber, and reaches the lower end surface of the piston. In the above case, the working principle of the communicating vessel is adopted, and the liquid level in the holding chamber needs to be always higher than or equal to the height of the lower end surface of the piston when the piston is at the original position, so as to ensure that the molten metal reaches the lower end surface of the piston after each return of the piston. There are two measures to maintain the liquid level in the holding chamber. One is to set the holding chamber at a high position, so as to maintain the liquid level in the holding chamber higher than or equal to the height of the lower end surface of the piston when the piston is at the original position. The other is to monitor or calculate the liquid level in the holding chamber, and add molten metal into the holding chamber when the liquid level is lower than the height of the lower end surface of the piston when the piston is at the original position. This can be realized by automatic device or manual monitoring and adding of molten metal, which will not be described herein. The other measure is to add inert gas above the liquid level in the holding chamber, so as to add a certain gas pressure to the liquid level in the holding chamber. When the molten metal is added into the pressure chamber, the molten metal can reach the lower end surface of the piston at the original position even if the liquid level in the holding chamber is lower than the height of the lower end surface of the piston at the original position. When this measure is adopted, the structure of the equipment becomes slightly complex due to the inert gas in the holding chamber and the certain pressure. The way of return of the piston is selected according to the type of the casting machine. The holding furnace adopting the structure of the present application has the following advantages. When the pressure is reduced, the liquid outlet of the holding chamber is closed, so that the molten metal after pressure reduction will not flow back into the holding chamber, and will not impact the molten metal in the holding chamber, and the phenomenon of backflow of the molten metal will not occur, and the phenomenon of turbulence of the molten metal in the holding chamber will not occur. When the piston returns, the pressure is released uniformly, so that the molten metal in the liquid lifting chamber, the communicating passage and the pressure chamber is withdrawn uniformly, and the liquid level is stable, and the liquid in the holding furnace will not be turbulent. Thus, the molten metal filled into the cavity is pure, and the phenomenon that the metal impurities caused by turbulence of the molten metal are filled into the cavity can be prevented.

[0042] The utility model discloses a quantitative provision of aluminum liquid to the cavity of low pressure metal casting machine is taken as an example to carry out the working process explanation. The basic structure of low pressure casting machine adopts the structure of prior art, including upper mould and lower mould, the internal cavity of upper mould and lower mould constitutes the cavity after closing, is provided with the pouring gate 504 at the bottom of lower mould, is provided with the sprue bushing 505 below the pouring gate, and the sprue bushing is sealed with the ascending liquid channel outlet channel intercommunication, is provided with the mould shunt cone 506 on the upper mould and the position opposite the sprue bushing, when needing to fill in the molten metal to the casting machine cavity, quantitative pressurization drive arrangement drives quantitative piston to move from the original position of quantitative piston to the set distance, quantitative delivery and pressurization to the molten metal, and the molten metal is filled into the mould cavity again through the pouring gate after passing through the sprue bushing in the ascending liquid channel outlet channel, and the area between the sprue bushing and the pouring gate constitutes the nozzle, and the molten metal that the nozzle sprays is guided and shunted into the mould cavity through the mould shunt cone, and the mould shunt cone guides the molten metal liquid from the die casting machine nozzle to each part of the mould cavity, ensures that the metal liquid can uniformly, quickly fill the cavity, reduces the defect in the filling process, simultaneously plays the shunt effect and divides the metal liquid into multiple streams, makes it more evenly distributed to the cavity, thereby improves the quality and performance of the casting, and the shunting of the metal liquid through the mould shunt cone can reduce the turbulence, effectively reduces the turbulence degree in the metal liquid flow process, reduces the generation of bubbles, inclusions. When filling is finished, the position of quantitative piston remains unchanged, and the quantitative, pressurization drive arrangement and piston continuously provide pressure for the molten metal liquid, when the molten metal in the mould cavity solidifies, quantitative pressurization drive arrangement drives quantitative piston to make partial return according to the pre-set displacement, that is, when returning, does not reset to the original position of quantitative piston but returns below the original position, makes the molten metal suspend, waits for the next quantitative delivery, repeats quantitative, pressurization, and each time return is partial return, keeps the molten metal suspended in the ascending liquid chamber, until when needing to supplement the molten metal to the pressurization chamber, quantitative pressurization drive arrangement drives quantitative piston to return to the original position, and the heat preservation furnace stopper makes corresponding action, so that when quantitative piston returns or after returning, the chamber and the pressurization chamber are communicated, and the molten metal enters into the pressurization chamber and the ascending liquid chamber, fills the pressurization chamber, and repeats the above quantitative, pressurization process.

[0043] In the utility model, in order to guarantee the high temperature resistance and service life of the quantitative piston cylinder and quantitative piston, the quantitative piston and quantitative piston cylinder inner cavity are preferably made of high temperature resistant ceramic material and other high temperature resistant materials, such as silicon nitride ceramic, and are movably connected in clearance fit with the inner cavity wall of the piston cylinder body, preferably movably connected in clearance fit self-sealing of molten metal liquid, since the molten metal liquid itself has certain surface tension, when the piston cylinder body and the piston are in clearance fit, the molten metal liquid can form liquid seal between the clearance of the two, therefore, the molten metal liquid below the piston is prevented from entering the piston cylinder inner cavity above the piston or the metal liquid in the piston cylinder inner cavity is very little, and at the same time, the smooth movement of the two is ensured.

[0044] The quantitative holding furnace with the structure of the utility model has the following advantages due to the adoption of the three-chamber structure of the holding chamber, the pressurizing chamber and the liquid lifting chamber: 1. Good temperature uniformity: through reasonable partition design, the aluminum liquid can be uniformly heated in different chambers, and the temperature difference is reduced, thereby ensuring the stability of the aluminum liquid quality. 2. Improved production efficiency: since the holding chamber is only used for containing the metal liquid, the holding chamber is closed when quantitative and pressurized feeding is performed, therefore, the metal liquid has sufficient heating and holding time in the holding chamber, the aluminum liquid can be continuously supplied, the production interruption caused by waiting for the aluminum liquid to warm up is reduced, thereby improving the overall production efficiency. 3. Reduced oxidation and slag inclusion: the holding chamber is closed when no metal liquid is added, providing a relatively stable environment, reducing the contact of the aluminum liquid with air, reducing the generation of oxidation and slag inclusion, and improving the purity of the aluminum liquid. 4. Easy to control and adjust: each chamber can be independently controlled in temperature and flow, and it is convenient to flexibly adjust according to production requirements.

Claims

1. A quantitative feeding device for a heat preservation furnace, characterized in that: The device includes a metering piston, a metering piston cylinder, a metering and pressurizing control system, and a metering and pressurizing drive device. The metering piston is located inside the piston cylinder and is slidably connected to the inner cavity surface of the piston cylinder with a clearance fit. The area below the metering piston in the inner cavity of the piston cylinder forms a pressurizing chamber, which is used to contain molten metal. The output end of the metering and pressurizing drive device is located inside the piston cylinder, and the upper surface of the metering piston is fixedly connected to the output end of the metering and pressurizing drive device. The metering and pressurizing control system is electrically connected to the metering and pressurizing drive device. The metering and pressurizing control system controls the metering and pressurizing drive device to drive the metering piston to move a set stroke inside the piston cylinder, thereby metering and pressurizing the molten metal from the pressurizing chamber. The pressurizing chamber receives the input molten metal. The metering and pressurizing drive device is a servo drive device, and the metering and pressurizing control system is a servo control system.

2. The quantitative feeding device for a heat preservation furnace as described in claim 1, characterized in that: The servo drive device is one of a servo hydraulic system, a servo electric cylinder, or a servo motor; or the pressurization chamber is used to communicate with the molten metal lifting device and the holding chamber set inside the furnace. The holding chamber is used to contain and keep the refined molten metal at a suitable temperature. Molten metal is supplied from the holding chamber to the pressurization chamber, and the molten metal output from the pressurization chamber is quantitatively and pressurized and output to the molten metal lifting device.

3. The quantitative feeding device for a heat preservation furnace as described in claim 1, characterized in that: The aforementioned metering piston and the gap between the piston cylinder cavity are fitted with a liquid-sealed movable connection.

4. A quantitative heat preservation furnace, characterized in that, The device includes a molten metal holding device, a holding furnace quantitative supply device, and a molten metal lifting device. The molten metal holding device includes a holding chamber furnace body, a holding furnace stopper rod, a holding furnace stopper rod driving device, a holding chamber heating device, and a holding chamber temperature detection device. A holding chamber outlet is provided at the bottom of the holding chamber furnace body, communicating with the inner cavity of the holding chamber. A holding furnace stopper rod passage is provided at the top of the holding chamber furnace body, through which the holding furnace stopper rod passes and is movably connected in a sealing fit with the holding furnace stopper rod. The center line of the holding furnace stopper rod passage is collinear with the center line of the holding chamber outlet. One end of the holding furnace stopper rod is located inside the holding chamber, and the other end is fixedly connected to the output end of the holding furnace stopper rod driving device. Under the drive of the holding furnace stopper rod driving device, the holding furnace stopper rod can close the holding chamber outlet or leave the holding chamber outlet. The holding chamber is used to contain molten metal and keep it at a constant temperature. The quantitative feeding device for the heat preservation furnace adopts the structure of the quantitative feeding device for the heat preservation furnace as described in any one of claims 1-3; The molten metal lifting device includes a lifting furnace, within which a lifting chamber is provided. The molten metal enters the mold cavity of the casting machine through the lifting chamber. The liquid-lifting chamber, pressurizing chamber, and holding chamber are interconnected below through a chamber communication channel. The liquid-lifting chamber and pressurizing chamber are freely connected, and the chamber communication channel is connected to the holding chamber through the liquid outlet of the holding chamber. When the quantitative supply device of the heat preservation furnace supplies liquid quantitatively and pressurized, the stopper rod of the heat preservation furnace enters the liquid outlet of the holding chamber and closes the liquid outlet of the holding chamber.

5. A quantitative heat preservation furnace as described in claim 4, characterized in that, The liquid lifting chamber is cylindrical in shape and includes a liquid lifting channel and a liquid lifting channel constriction section. A liquid lifting channel outlet channel is provided at the liquid lifting channel outlet end of the liquid lifting channel constriction section. The liquid lifting channel constriction section is connected to the liquid lifting channel outlet end through its small diameter end.

6. A quantitative heat preservation furnace as described in claim 4, characterized in that, The holding chamber, pressurizing chamber, and liquid-lifting chamber are arranged side by side. The liquid-lifting chamber is cylindrical in shape, and the liquid outlet of the liquid-lifting channel opens upward.

7. A quantitative heat preservation furnace as described in claim 4, characterized in that, A metering and pressurizing drive device drives a metering piston to move a predetermined distance downwards from its original position, pressurizing and metering the molten metal in the pressurizing chamber. The metering and pressurizing control system controls the stroke of the metering piston in one of the following ways: After metering and pressurizing are completed, the metering and pressurizing drive device remains stationary, keeping the metering piston in its original position after filling and pressurizing. When the next filling is required, the piston continues to move downwards a predetermined distance from its original position after filling and pressurizing, repeating this downward movement multiple times until the piston returns to its original position. The holding furnace stopper is then opened, and molten metal is introduced from the holding chamber into the pressurizing chamber and the rising chamber, suspending the molten metal in the rising chamber. When the next pressurizing and filling is required, the piston moves downwards from its original position as per the metering and pressurizing drive device... Driven to move down a set distance again until, after multiple filling and pressurization cycles, when molten metal needs to be added to the rising and pressurizing chambers, the metering and pressurizing drive device drives the piston back to the origin position. Then, the furnace stopper opens again, allowing the molten metal in the chamber to flow back into the pressurizing chamber, rising chamber, and connecting channel to reach the preset height. The furnace stopper then closes the outlet of the holding chamber again, and the metering and pressurizing drive device drives the piston down in segments according to the set stroke until molten metal needs to be added to the pressurizing and rising chambers again. This metering and pressurization process is repeated. When the metering piston returns to the origin position, the level of molten metal in the holding chamber must be higher than or equal to the height of the lower end face of the metering piston when it is at the origin position. Alternatively, after each metered supply and pressurized filling is completed, the piston returns to its original position and then moves downward from the original position to metered supply and pressurized filling. At the same time, the stopper rod of the holding furnace makes corresponding movements so that when the piston returns, the holding chamber and the pressurizing chamber are connected, allowing the molten metal to enter the pressurizing chamber and the rising chamber, reaching the bottom of the piston and contacting the piston. When the metered piston returns to its original position, the liquid level of the molten metal in the holding chamber must be higher than or equal to the height of the lower end face of the metered piston when it is at the original position. Alternatively, the metering and pressurizing drive device moves the metering piston down a set distance from its origin position, metering and pressurizing the molten metal. The molten metal enters the mold cavity from the liquid outlet channel of the rising liquid channel. After filling, the metering piston remains stationary, and the metering and pressurizing drive device and the metering piston continuously provide pressure to the molten metal. When the molten metal in the mold cavity solidifies, the metering and pressurizing drive device drives the metering piston to partially return to a pre-set displacement, returning the metering piston to below its origin position, causing the molten metal to suspend in the rising liquid chamber, awaiting the next metering delivery. This metering and pressurizing process is repeated multiple times. The pressurization process involves partial return strokes each time, keeping the molten metal suspended in the rising chamber until the pressurization chamber needs additional molten metal. At this point, the metering and pressurization drive device returns the metering piston to its original position, and the furnace stopper rod performs the corresponding action. This ensures that the chamber and the pressurization chamber are connected when the piston returns to its original position or afterward, allowing the molten metal to enter both chambers. This metering and pressurization process is repeated multiple times, with each return stroke being a partial return stroke, keeping the molten metal suspended in the rising chamber until the pressurization chamber needs additional molten metal again. At this point, the metering and pressurization drive device returns the metering piston to its original position, and the cycle repeats continuously.

8. A quantitative heat preservation furnace as described in claim 7, characterized in that, Molten metal is added to the holding chamber when the liquid level of the molten metal in the holding chamber is equal to or lower than the height of the lower end face of the metering piston when it is in the origin position.

9. A metal casting system, characterized in that, It includes a casting machine and a quantitative holding furnace, wherein the quantitative holding furnace adopts the quantitative holding furnace with the structure described in any one of claims 4-8.

10. A metal casting system as described in claim 9, characterized in that, The casting machine is one of a low-pressure casting machine, a high-pressure casting machine, a differential pressure casting machine, or a squeeze casting machine, and is connected to the mold cavity of the casting machine through a liquid riser chamber.

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