Fully automatic production process for battery pack boxes

Abstract

The present invention discloses a fully automatic production process for a battery pack box, comprising the following steps: smelting - die casting - trimming - shot blasting - machining - cleaning - packaging and storage. The present invention strictly controls the feed ratio of aluminum ingots and waste materials in the smelting raw materials, and performs slag removal on the molten metal aluminum liquid, effectively reducing the impurity content of the metal aluminum liquid, ensuring the subsequent product quality, and during die casting, the mold is temperature-controlled and vacuumed in advance, and the temperature control is used to ensure that the mold reaches a suitable temperature before the metal aluminum liquid is injected into the mold, thereby improving the quality and surface finish of the box, and the vacuum treatment in the mold can realize high-speed filling and high-pressure solidification molding of the die-casting machine, effectively eliminating gas defects in the box, such as bubbles, pores and air gaps, and further improving the quality and surface finish of the box.

Description

Technical Field

[0001] The present invention belongs to the technical field of battery pack case processing, and in particular relates to a fully automatic production process for a battery pack case. Background Art

[0002] The battery pack shell is the main carrier of the battery pack system of new energy vehicles. Its main function is to provide a mounting structure for each system component inside the battery pack and to protect each component. In addition, the battery pack shell is also the main structural component in the battery pack system. After carrying the entire battery pack system, it is installed with the vehicle body to meet the requirements of providing electricity for new energy vehicles. In the prior art, the battery pack shell is formed by die casting. However, during the die casting process, there are many impurities in the molten aluminum metal, which affects the subsequent product quality. After the aluminum metal is hydraulically cast, the casting has many cold shuts and pores, resulting in a low product qualification rate, affecting processing efficiency and increasing processing costs. Moreover, the castings after die casting are generally cooled by natural air cooling, which takes a long time to cool and has poor cooling effect, which prolongs the production cycle and affects production efficiency. Summary of the invention

[0003] The purpose of the present invention is to provide a technical solution for a fully automatic production process of a battery pack case in view of the shortcomings of the prior art. The design is ingenious and reasonable, the feed ratio of aluminum ingots and scrap in the smelting raw materials is strictly controlled, and the molten metal aluminum liquid is subjected to slag removal treatment, so as to effectively reduce the impurity content of the metal aluminum liquid and ensure the subsequent product quality. During die-casting, the mold is temperature-controlled and vacuum-treated in advance. The temperature control is used to ensure that the mold reaches a suitable temperature before the metal aluminum liquid is injected into the mold, thereby improving the quality and surface finish of the case. The vacuum treatment in the mold can realize high-speed filling and high-pressure solidification molding of the die-casting machine, effectively eliminate gas defects in the case, such as bubbles, pores and air gaps, and further improve the quality and surface finish of the case.

[0004] In order to solve the technical problem, the present invention adopts the following technical solution:

[0005] The fully automatic production process of battery pack box includes the following steps:

[0006] Step 1: Smelting: Add the raw materials into the melting furnace to melt, and put the aluminum ingots and scraps into the melting furnace at a feed ratio of 7:3 to melt and form aluminum liquid;

[0007] Step 2: Die Casting:

[0008] (1) Add the molten aluminum liquid to the quantitative furnace for heat preservation. The quantitative pump in the quantitative furnace transports the aluminum liquid to the die-casting machine material pipe through the heating chute according to the set value. The quantitative accuracy of the quantitative furnace is ≤±1%, and the quantitative speed is 8-10kg / s. Then, the aluminum liquid is transported to the pressure chamber of the die-casting machine through the die-casting machine material pipe, and then injected into the mold cavity after the mold is closed through the pressure chamber. During the die-casting process, the casting pressure of the die-casting machine is 70-100Mpa;

[0009] The dosing furnace is used to control the closed constant temperature of the metal aluminum liquid, and transport the metal aluminum liquid to the mold through the heating chute and the die-casting machine material pipe under a certain pressure (30-60MPa); the dosing furnace is a fully sealed new type of insulation furnace that combines the insulation furnace and the air pressure dosing device. It has the characteristics of high degree of automation, low energy consumption for insulation, excellent heat conduction efficiency, dosing accuracy of ±1%, perfect aluminum liquid quality, and easy operation.

[0010] (2) Before injecting the aluminum liquid into the mold cavity, the temperature of the mold is adjusted by a mold temperature controller, which includes an oil temperature controller and a water temperature controller. Both the oil temperature controller and the water temperature controller are connected to the mold pipeline through pipelines. The thermal oil delivery pump in the oil temperature controller delivers the thermal oil to the mold pipeline, and the pure water delivery pump in the water temperature controller delivers the heated pure water to the mold pipeline. The mold is temperature-controlled by the thermal oil and the heated pure water, and the mold temperature is monitored by a temperature detection imager until the mold temperature reaches the set temperature value;

[0011] The mold temperature can be adjusted by heat-conducting oil or high-temperature pure water to achieve rapid heating or cooling of the mold. The mold can be heated to the desired temperature or cooled to a suitable temperature in a short time. At the same time, it has the ability to quickly heat up and cool down, and can accurately control the temperature of the mold to ensure that the metal material reaches a suitable temperature before being injected into the mold, thereby improving the quality and surface finish of the box. Through the design of the oil temperature machine and the water temperature machine, not only can the temperature in the mold be well controlled to improve the die-casting efficiency, but also the cost can be greatly reduced, thereby reducing energy consumption. In addition, in the present application, multiple oil temperature machines and water temperature machines are provided, and the mold temperature is controlled by multiple oil temperature machines and water temperature machines to ensure the mold temperature adjustment rate.

[0012] (3) Before the aluminum liquid is injected into the mold cavity, the mold is vacuumed by a vacuum machine;

[0013] By vacuuming the mold, the porosity inside the box is reduced, the internal structure of the box is made dense, the mechanical properties of the die-casting are improved, and gas defects such as bubbles, pores and air gaps are effectively eliminated, thereby improving the quality and surface finish of the box.

[0014] (4) Demolding: The pick-up robot takes out the die-cast box and puts it into the machine-side cooling station for cooling. The machine-side cooling station uses a spray or jet method to supply water, and the cooling water evenly wets the surface of the box to cool the surface of the box. Then, the spray system is used to spray the surface of the movable mold and the fixed mold after the mold is opened;

[0015] The high-pressure castings are cooled by the machine-side cooling station, and the high-pressure castings after forming are cooled by spraying or injection. At the same time, the machine-side cooling station adopts a coil internal cooling design, and the cooling water circuit booster pump accelerates the flow rate to achieve rapid cooling of the product and improve the mechanical performance.

[0016] A spraying system is used to spray the release agent onto the surface of the movable mold and the fixed mold after mold opening, so as to facilitate the demoulding process of the high-pressure casting and to cool the movable mold and the fixed mold after mold opening.

[0017] Step 3: trimming: the die-casting trimming machine is used to trim the box body after demoulding and cooling. The die-casting trimming machine uses a plasma beam to trim the box body;

[0018] Step 4: Shot blasting: Grind the box after trimming, put the box into the shot blasting machine for shot blasting, spray 0.15-0.5mm steel shot in the shot blasting machine, shot blast the box for 3-5 minutes, and turn the box synchronously in the shot blasting machine during the shot blasting process;

[0019] Step 5: Machining: transport the shot blasted box to the machining workshop for machining;

[0020] Step 6: Cleaning: transport the machined box to the cleaning workshop and perform ultrasonic cleaning on the box;

[0021] Step 7: Packing and warehousing: Inspect the surface of the box after cleaning, then pack and warehousing.

[0022] Furthermore, in the above step one, before the metal aluminum liquid is transported to the quantitative furnace, a slag remover is added to the metal aluminum liquid, stirred for 2-3 minutes, and then allowed to stand for 12-20 minutes, and then solid-liquid separation is performed to remove the solid slag, leaving the metal aluminum liquid after slag removal.

[0023] Furthermore, the molten aluminum is tested after slag removal to ensure that the density equivalent of the molten aluminum is ≤±3%.

[0024] Furthermore, in step (4) of the above step 2, before the pickup robot takes out the box and puts it into the machine-side cooling station, it first performs a laser integrity inspection on the box. The inspection process is as follows:

[0025] a. The boxes that have passed the inspection enter the machine side cooling station for cooling, and then undergo edge trimming. After edge trimming, the subsequent processing steps are carried out in sequence;

[0026] b. The boxes that fail the inspection are sent to the machine side cooling station for cooling, and then the trimming operation is carried out. After the trimming operation, the unqualified boxes are sent to the unloading trolley by the robot.

[0027] Further, in step (4) of the above step 2, the spraying operation of the spraying system is as follows:

[0028] a. The spraying system includes a release agent proportioning device, a water-gas distribution cabinet, a gas storage tank and a robot spray head assembly. The release agent proportioning device and the gas storage tank are connected to the water-gas distribution cabinet, the water-gas distribution cabinet is connected to the robot spray assembly, a flow meter is provided on the pipeline between the water-gas distribution cabinet and the robot spray assembly, and the robot spray head assembly includes a first spray robot and a second spray robot;

[0029] b. The first spraying robot corresponds to the movable mold in the mold, and the second spraying robot corresponds to the fixed mold in the mold. The first spraying robot and the second spraying robot are both provided with spraying heads. The release agent proportioning device conveys the release agent to the water-gas distribution cabinet, and the gas storage tank conveys the gas to the water-gas distribution cabinet. The water-gas distribution cabinet distributes the release agent and gas to the first spraying robot and the second spraying robot, and then sprays them out from the spraying heads in the form of droplets to spray the surfaces of the movable mold and the fixed mold;

[0030] c. Distribute the release agent and gas to the first spray robot and the second spray robot in the water-gas distribution cabinet, and control the distribution flow rate through a flow meter.

[0031] Furthermore, the spray head includes a liquid separation plate, an air blowing pipe and a nozzle, and the air blowing pipe and the nozzle are distributed on the liquid separation plate. It can realize fast linkage spraying of the moving mold and the fixed mold, and integrate multiple modes such as mixed spraying, micro spraying, and in-film spraying to meet various process requirements.

[0032] Furthermore, in the above step 2, an exhaust gas purification system is arranged above the die-casting machine. The exhaust gas purification system cover is arranged above the die-casting machine, and the exhaust gas generated during the die-casting process is collected and treated by the exhaust gas purification system.

[0033] Furthermore, in step (3) of the above step 2, the vacuuming step of the vacuum machine is as follows:

[0034] a. The vacuum machine includes a front-stage vacuum pump and a vacuum tank. The front-stage vacuum pump is connected to the vacuum tank through a vacuum pipeline. A filter is provided at the inlet of the front-stage vacuum pump. A vacuum interface is connected to the vacuum pipeline. The vacuum interface is connected to the mold cavity through a vacuum channel. A pneumatic butterfly valve and a mechanical vacuum gauge are provided on the vacuum pipeline. A manual butterfly valve is provided on the vacuum interface. A vacuum sensor is provided on the vacuum tank.

[0035] b. Open the pneumatic butterfly valve and start the fore vacuum pump. The fore vacuum pump evacuates the vacuum tank and measures the pressure value in the vacuum tank through the vacuum sensor. When the pressure value in the vacuum tank reaches the set value, close the pneumatic butterfly valve and the fore vacuum pump. The vacuum tank reaches a vacuum state and forms a negative pressure. During the process of the fore vacuum pump evacuating the vacuum tank, the air must be filtered by the filter before entering the fore vacuum pump.

[0036] c. Open the manual butterfly valve, and the air in the mold cavity will diffuse into the vacuum tank along the vacuum channel, vacuum interface, and vacuum pipeline until the vacuum in the mold pipeline is lower than 3mbar and the vacuum in the mold cavity is lower than 40mbar. Then close the manual butterfly valve and the vacuum process stops.

[0037] The vacuum machine can be used to evacuate the mold to achieve high-speed filling and high-pressure solidification molding of the die-casting machine. The vacuum machine has a fast collection speed and good vacuum exhaust effect, which reduces the back pressure in the cavity, which is beneficial to extend the life of the die-casting mold, and reduces the porosity inside the box, making the internal structure of the box dense, improving the mechanical properties of the die-casting, and effectively eliminating gas defects such as bubbles, pores and air gaps, thereby improving the quality and surface finish of the box. The vacuum machine can evacuate the mold pipeline to less than 3mbar, and the mold cavity to less than 40mbar. The vacuum parameters of the process detection can be measured, detected and visualized. The vacuum machine can provide a stable and pulsation-free vacuum, and only needs regular maintenance under normal operation. It is easy and simple to use.

[0038] Furthermore, in step (1) of the above step 2, during the die-casting process, the casting pressure of the die-casting machine is 70-100 MPa.

[0039] Furthermore, in step (1) of the above step 2, the quantitative accuracy of the quantitative furnace is ≤±1%, and the quantitative speed is 8-10 kg / s.

[0040] The present invention has the following beneficial effects due to the adoption of the technical solution:

[0041] The present invention is cleverly and reasonably designed, strictly controls the feed ratio of aluminum ingots and scrap in the smelting raw materials, and performs slag removal on the molten aluminum liquid, effectively reducing the impurity content of the aluminum liquid and ensuring the quality of subsequent products. During die-casting, the mold is temperature-controlled and vacuumed in advance, and the temperature control is used to ensure that the mold reaches a suitable temperature before the aluminum liquid is injected into the mold, thereby improving the quality and surface finish of the box. The vacuum treatment in the mold can realize high-speed filling and high-pressure solidification molding of the die-casting machine, effectively eliminating gas defects in the box, such as bubbles, pores and air gaps, and further improving the quality and surface finish of the box. Compared with the traditional battery pack that uses aluminum profile welding processing technology, the production process of this application can omit the welding process and greatly improve the airtightness qualification rate of the product.

[0042] The present invention adopts an aluminum alloy quantitative furnace of 6T or above, and the quantitative speed can reach 10kg / s, and the quantitative accuracy is within ±1%, which can quickly and accurately quantify, and continuously and stably output, while the density equivalent of aluminum liquid is controlled within ±3%. The quantitative furnace has extremely high energy efficiency, extremely low metal burning loss and excellent heat conduction performance, and saves energy by up to 80% compared with traditional quantitative furnaces. At the same time, it adopts a fully sealed structure to reduce oxidation.

[0043] The present invention adopts a dual-concentration mixed ratio spraying system. The system realizes dual-proportion concentration release agent output. The ratio of release agent to water is adjustable in the range of 1:0 to 1:500. The maximum output pressure of the release agent can reach 1.2Mpa. The dual robots are equipped with contoured spray heads for operation. The dual spray heads can realize fast linkage spraying of dynamic and fixed molds, and integrate multiple modes such as mixed spraying, micro-spraying, and in-membrane spraying to meet various process requirements. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] The present invention will be further described below in conjunction with the accompanying drawings:

[0045] Figure 1 This is a flow chart of the fully automatic production process of the battery pack box of the present invention;

[0046] Figure 2 It is a schematic diagram of the installation position structure between the dosing furnace and the die-casting machine in the present invention;

[0047] Figure 3 It is a structural schematic diagram of the die-casting machine in the present invention;

[0048] Figure 4 for Figure 3 Schematic diagram of the structure in the AA direction;

[0049] Figure 5 It is a structural schematic diagram of the oil temperature machine in the present invention;

[0050] Figure 6for Figure 5 Schematic diagram of the structure in the B direction;

[0051] Figure 7 It is a structural schematic diagram of the spraying system in the present invention;

[0052] Figure 8 This is a rendering of the vacuum machine in the present invention;

[0053] Fig. 9 It is the effect diagram of the quantitative furnace in the present invention.

[0054] In the figure: 1-dosing furnace; 101-heating chute; 102-track; 2-die casting trimming machine; 3-piece picking robot; 4-die casting machine; 401-waste gas purification system; 402-mold; 5-oil temperature machine; 501-machine casing; 502-PLC controller; 503-hot oil inlet; 504-hot oil outlet; 6-water temperature machine; 7-machine side cooling station; 8-vacuum machine; 801-front vacuum pump; 802-vacuum tank; 803-filter; 804- Vacuum interface; 805-pneumatic butterfly valve; 806-mechanical vacuum gauge; 807-manual butterfly valve; 808-vacuum sensor; 809-drain outlet; 9-spraying system; 901-release agent proportioning equipment; 902-water and gas distribution cabinet; 903-gas storage tank; 904-first spraying robot; 905-second spraying robot; 906-spraying head; 907-liquid separation plate; 908-air blowing pipe; 909-nozzle; 910-flow meter; 911-shock-absorbing base. DETAILED DESCRIPTION

[0055] like Figures 1 to 9 As shown, the fully automatic production process of the battery pack box of the present invention includes the following steps:

[0056] Step 1: Smelting: Add the raw materials into the melting furnace to melt, and put the aluminum ingots and scraps into the melting furnace at a feed ratio of 7:3 to melt and form aluminum liquid;

[0057] Step 2, die casting: an exhaust gas purification treatment system 401 is arranged above the die casting machine 4, and the exhaust gas purification treatment system 401 cover is arranged above the die casting machine 4, and the exhaust gas generated during the die casting process is collected and treated by the exhaust gas purification treatment system 401; the exhaust gas purification treatment system 401 can wrap the die casting machine 4 through columns, square tubes, sheet metal, dust curtains, and covers, and is used to treat the exhaust gas, such as smoke, water vapor, aluminum alloy dust, carbon dioxide, etc., generated during the casting process, which may pollute the environment;

[0058] Die casting includes the following steps:

[0059] (1) Add the molten aluminum liquid to the quantitative furnace 1 for heat preservation. The quantitative pump in the quantitative furnace 1 delivers the aluminum liquid to the die casting machine material pipe through the heating chute 101 according to the set value, and then delivers it to the pressure chamber of the die casting machine 4 through the die casting machine material pipe. Then, the aluminum liquid is injected into the mold cavity of the mold 402 after the mold is closed through the pressure chamber. The quantitative accuracy of the quantitative furnace 1 is ≤±1%, and the quantitative speed is 8-10kg / s. Before the aluminum liquid is delivered to the quantitative furnace 1, a slag remover is added to the aluminum liquid, stirred for 2-3 minutes, and then left for 12-20 minutes, and then solid-liquid separation is performed to remove the solid slag and leave the aluminum liquid after slag removal. By adding the slag remover and stirring, the gas and metal impurities in the aluminum liquid are removed, the purity of the aluminum liquid is improved, and the subsequent box quality is improved. After slag removal, the aluminum liquid after slag removal is further tested to ensure that the density equivalent of the aluminum liquid is ≤±3%, thereby ensuring the cleanliness of the aluminum liquid.

[0060] The dosing furnace 1 is used to control the closed constant temperature of the metal aluminum liquid, and transport the metal aluminum liquid to the mold 402 through the heating chute 101 and the die casting machine material pipe under a certain pressure (30-60MPa); the dosing furnace 1 is a fully sealed new type of insulation furnace that combines the insulation furnace and the air pressure dosing device together, and has the characteristics of high degree of automation, low energy consumption for insulation, excellent heat conduction efficiency, dosing accuracy ±1%, perfect aluminum liquid quality, and easy operation. Using 6T and above aluminum alloy dosing furnace 1, the dosing speed can reach 10kg / s, and the dosing accuracy is within ±1%. It can dosing quickly and accurately, and continuously and stably output, and the density equivalent of aluminum liquid is controlled within ±3%. The dosing furnace 1 has extremely high energy efficiency, extremely low metal burning loss and excellent heat conduction efficiency. Compared with the traditional dosing furnace 1, it saves energy by up to 80%, and adopts a fully sealed structure to reduce oxidation.

[0061] The dosing furnace 1 degasses and insulates the molten aluminum metal, and transports it to the pressure chamber of the die-casting machine 4 through the heating chute 101 and the die-casting machine material pipe according to the set value through the dosing pump inside the dosing furnace 1. The vacuum machine 8 evacuates the mold 402, and the die-casting machine 4 injects the aluminum metal liquid into the mold 402 through the pressure chamber. The aluminum metal liquid cools and condenses under high pressure to form a high-pressure casting. The dosing furnace 1 is equipped with a track 102, and the dosing furnace 1 can move along the track 102, thereby meeting the transportation requirements of the aluminum metal liquid.

[0062] The die-casting machine 4 is used to hydraulically inject molten aluminum metal into the mold 402 to form the required high-pressure castings. The die-casting machine 4 in the present invention adopts a direct-pressure clamping column frame structure and is combined with the latest generation of high-dynamic response injection system of Lijin. The biggest feature of this system is fast injection response, short filling time, strong injection performance, larger injection capacity and clamping force, and stronger pressure and more stable control system. It can handle larger-sized molds 402 and larger volumes of metal materials, thereby improving production capacity and achieving higher injection accuracy and better part consistency. This application uses a 6,600-ton Lijin die-casting machine 4 with a clamping force of 6,600 tons, a casting pressure of 70 to 100 MPa, a template size of more than 3,500 mm, and a maximum casting area of ​​up to 15,000 cm 2 The die-casting machine 4 is connected to the double closed-loop real-time control system of the injection unit, which meets the requirements of the battery pack, front cabin and rear body of new energy vehicles, and can realize an efficient casting process.

[0063] (2) Before injecting the molten aluminum into the cavity of the mold 402, the temperature of the mold 402 is adjusted by a mold temperature controller. The mold temperature controller includes an oil temperature controller 5 and a water temperature controller 6. The oil temperature controller 5 and the water temperature controller 6 are both connected to the pipeline of the mold 402 through a pipeline. The thermal oil delivery pump in the oil temperature controller 5 delivers the thermal oil to the pipeline of the mold 402, and the pure water delivery pump in the water temperature controller 6 delivers the heated pure water to the pipeline of the mold 402. The mold 402 is temperature-controlled by the thermal oil and the heated pure water, and the temperature of the mold 402 is monitored by a temperature detection imager until the temperature of the mold 402 reaches the set temperature value. A hot oil inlet 503 and a hot oil outlet 504 are provided on the housing 501 of the oil temperature controller 5. A PLC controller 502 is provided on the housing 501 of the oil temperature controller 5 and the water temperature controller 6. The PLC controller 502 has high stability, reliability, simple operation, and is easy to maintain.

[0064] The temperature of the mold 402 can be adjusted by heat-conducting oil or high-temperature pure water to achieve rapid heating or cooling of the mold 402. The mold 402 can be heated to the desired temperature or cooled to a suitable temperature in a short time. At the same time, it has the ability to quickly heat up and cool down, and can accurately control the temperature of the mold 402 to ensure that the metal material reaches a suitable temperature before being injected into the mold 402, thereby improving the quality and surface finish of the box. Through the design of the oil temperature machine 5 and the water temperature machine 6, not only can the temperature in the mold 402 be well controlled to improve the die-casting efficiency, but also the cost can be greatly reduced, thereby reducing energy consumption. In addition, in the present application, multiple oil temperature machines 5 and water temperature machines 6 are provided, and the temperature of the mold 402 is controlled by multiple oil temperature machines 5 and water temperature machines 6 to ensure the temperature adjustment rate of the mold 402. The oil temperature machine 5 preferably uses 10 dual-circuit oil temperature machines 5, with a total oil storage capacity of 80L, an output thermal oil temperature of up to 320°C, independent dual-circuit control, a maximum flow of 100L / min, a maximum head of 100m, and a temperature control accuracy of up to ±1°C, which meets the requirements of rapid heating and continuous constant temperature of the new energy super-large mold 402. The water temperature machine 6 preferably uses 30 dual-circuit water temperature machines 6, and the output mold 402 pipeline circulating water temperature can reach 180°C, independent dual-circuit control, a maximum flow of 120L / min, a maximum head of 100m, and a temperature control accuracy of up to ±1°C, which meets the requirements of rapid heating and continuous constant temperature of the new energy super-large mold 402.

[0065] (3) Before the aluminum liquid is injected into the mold cavity of the mold 402, the mold 402 is vacuumed by a vacuum machine 8;

[0066] The steps of vacuuming the vacuum machine 8 are as follows:

[0067] a. The vacuum machine 8 includes a front-stage vacuum pump 801 and a vacuum tank 802. The front-stage vacuum pump 801 is connected to the vacuum tank 802 through a vacuum pipeline. A filter 803 is provided at the inlet of the front-stage vacuum pump 801. A vacuum interface 804 is connected to the vacuum pipeline. The vacuum interface 804 is connected to the mold cavity 402 through a vacuum channel. A pneumatic butterfly valve 805 and a mechanical vacuum gauge 806 are provided on the vacuum pipeline. A manual butterfly valve 807 is provided on the vacuum interface 804. A vacuum sensor 808 is provided on the vacuum tank 802. A sewage outlet 809 is also provided at the bottom of the vacuum tank 802 to facilitate regular sewage discharge and cleaning of the inside of the vacuum tank 802.

[0068] b. Open the pneumatic butterfly valve 805 and start the fore vacuum pump 801. The fore vacuum pump 801 evacuates the vacuum tank 802 and measures the pressure value in the vacuum tank 802 through the vacuum sensor 808. When the pressure value in the vacuum tank 802 reaches the set value, close the pneumatic butterfly valve 805 and the fore vacuum pump 801. The vacuum tank 802 reaches a vacuum state and forms a negative pressure. During the process of the fore vacuum pump 801 evacuating the vacuum tank 802, the air must be filtered by the filter 803 before entering the fore vacuum pump 801, thereby protecting the interior of the fore vacuum pump 801 and extending its service life.

[0069] c. Open the manual butterfly valve 807, and the air in the mold cavity of the mold 402 diffuses into the vacuum tank 802 along the vacuum channel, vacuum interface 804, and vacuum pipeline until the vacuum in the pipeline of the mold 402 is lower than 3 mbar and the vacuum in the mold cavity of the mold 402 is lower than 40 mbar. Then close the manual butterfly valve 807 and the vacuum process stops.

[0070] By vacuuming the mold 402, the porosity inside the box is reduced, the internal structure of the box is made dense, the mechanical properties of the die casting are improved, and gas defects such as bubbles, pores and air gaps are effectively eliminated, thereby improving the quality and surface finish of the box. The vacuum machine 8 vacuums the mold 402 to achieve high-speed filling and high-pressure solidification molding of the die-casting machine 4. The vacuum machine 8 has a fast acquisition speed and a good vacuum exhaust effect, which reduces the back pressure in the cavity, which is conducive to extending the life of the die-casting mold 402, and reduces the porosity inside the box, making the internal structure of the box dense, improving the mechanical properties of the die casting, and effectively eliminating gas defects such as bubbles, pores and air gaps, thereby improving the quality and surface finish of the box. The vacuum machine 8 can make the mold 402 pipeline vacuum less than 3mbar, the mold cavity of the mold 402 vacuum less than 40mbar, and the vacuum parameters of the process detection can be measured, detected and visualized, which is more convenient for actual operation. The vacuum machine 8 can provide a stable and pulsating vacuum, and only needs regular maintenance under normal operation, which is convenient and simple to use.

[0071] The vacuum machine 8 of the present invention adopts a 6000L ultra-high multi-channel vacuum machine 8, with a suction capacity of up to 2000m³ / h, a static vacuum degree ≤5mbar, a dynamic vacuum degree ≤50mbar, and a system response time ≤35ms. The equipment is equipped with 1 set of barrel vacuum channels, 8 sets of mold 402 vacuum channels and 4 sets of hydraulic valve control units to meet the vacuum requirements of new energy super-large molds 402.

[0072] (4) Demolding: The pick-up robot 3 takes out the die-cast box and puts it into the machine-side cooling station 7 for cooling. The machine-side cooling station 7 supplies water by spraying or jetting, and evenly wets the surface of the box with cooling water to cool the surface of the box. Rapid cooling is achieved through water cooling to avoid deformation or unevenness of the box caused by excessive temperature differences, thereby improving production efficiency. The pick-up robot 3 grabs and carries the box, making the entire process highly automated. Then, the spraying system 9 is used to spray the surfaces of the movable mold and the fixed mold after mold opening;

[0073] Before the picking robot 3 takes out the box and puts it into the machine-side cooling station 7, the box is first subjected to integrity laser inspection. The inspection process is as follows:

[0074] a. The box body that has passed the inspection enters the machine side cooling station 7 for cooling, and then performs the edge trimming operation after cooling, and then performs the subsequent processing steps in sequence after the edge trimming operation;

[0075] b. The unqualified boxes are sent to the machine side cooling station 7 for cooling, and then the edge trimming operation is performed. After the edge trimming operation, the unqualified boxes are sent to the unloading trolley by the manipulator.

[0076] The high-pressure casting is cooled by the machine-side cooling station 7, and the high-pressure casting after forming is cooled by spraying or jetting. At the same time, the machine-side cooling station 7 adopts a coil internal cooling design, and the cooling water booster pump accelerates the flow rate to achieve the effect of rapid cooling of the product and improving the mechanical performance. The machine-side cooling station 7 is simple in design and easy to install and maintain. At the same time, the cooling water is recycled and can be recycled through equipment such as cooling towers or heat exchangers, reducing water consumption and drainage.

[0077] The spraying system 9 is used to spray the release agent onto the surface of the movable mold and the fixed mold after the mold is opened, which is convenient for the demoulding process of the high-pressure casting, and the movable mold and the fixed mold after the mold is opened are cooled. The spraying system 9 sprays the release agent onto the surface of the mold 402 in the form of high-speed spray, effectively locally cools the mold 402, and quickly reduces the temperature of the surface of the mold 402. This spraying method has the characteristics of fast, uniform and efficient. At the same time, it is equipped with an advanced control device, which can monitor and adjust the spray volume, spray angle, spray pressure and other parameters in real time to achieve accurate spraying control. At the same time, the spraying system 9 is equipped with an automatic air pressure adjustment unit, and atomization and drying use different air pressure modules for accurate profiling. The spraying system 9 also has force, flow, and alarm functions, all of which are shared with the die-casting machine 4 and the surrounding automation, can be viewed remotely, and the operation is simple and convenient, which greatly reduces the labor intensity of manual operation, and the whole system has high control accuracy.

[0078] The spraying operation of the spraying system 9 is as follows:

[0079] a. The spraying system 9 includes a release agent proportioning device 901, a water-gas distribution cabinet 902, a gas storage tank 903 and a robot spray head assembly. The release agent proportioning device 901 and the gas storage tank 903 are both connected to the water-gas distribution cabinet 902, and the water-gas distribution cabinet 902 is connected to the robot spray assembly. A flow meter 910 is provided on the pipeline between the water-gas distribution cabinet 902 and the robot spray assembly. The robot spray head assembly includes a first spray robot 904 and a second spray robot 905; the first spray robot 904 and the second spray robot 905 are both provided with a shock-absorbing base 911 to facilitate the installation and fixation of the first spray robot 904 and the second spray robot 905;

[0080] b. The first spraying robot 904 corresponds to the movable mold in the mold 402, and the second spraying robot 905 corresponds to the fixed mold in the mold 402. The first spraying robot 904 and the second spraying robot 905 are both provided with a spraying head 906. The mold release agent proportioning device 901 delivers the mold release agent to the water-gas distribution cabinet 902, and the gas storage tank 903 delivers the gas to the water-gas distribution cabinet 902. The water-gas distribution cabinet 902 distributes the mold release agent and gas to the first spraying robot 904 and the second spraying robot 905, and then sprays them from the spraying head 906 in the form of droplets to spray the surfaces of the movable mold and the fixed mold; the spraying head 906 includes a liquid separation plate 907, an air blowing pipe 908 and a nozzle 909, and the air blowing pipe 908 and the nozzle 909 are distributed on the liquid separation plate 907. It can realize fast linkage spraying of the movable and fixed molds, and integrate multiple modes such as mixed spraying, micro-spraying, and in-film spraying to meet various process requirements.

[0081] c. In the water-gas distribution cabinet 902 , the release agent and gas are distributed to the first spraying robot 904 and the second spraying robot 905 , and the distribution flow is controlled by the flow meter 910 .

[0082] Step 3, trimming: The die-casting trimming machine 2 is used to trim the box body after demolding and cooling. The die-casting trimming machine 2 uses a plasma beam to trim the box body; the trimming operation is used to remove the material cake, runner, slag bag and exhaust of the high-pressure casting, and the high energy density and instantaneous high temperature of the plasma are used to melt the metal material, thereby realizing the cutting, welding and other processes, with fast cutting speed, high efficiency and good effect. Plasma cutting is not limited by the type of material and can be used to cut various metal and non-metal materials, such as steel, aluminum, copper, stainless steel, glass, plastic, etc., and has a wide range of adaptability. The tooling of the die-casting trimming machine 2 in this application adopts 4-point support, belt in-place detection, 1-point in-place detection, and uses Miyi ILD1320-100 distance sensor to detect product deformation. The use of an automated control system can complete the automated operation of the entire trimming process. By setting appropriate parameters and programs, stable and efficient trimming operations can be achieved.

[0083] Step 4: Shot blasting: Grind the box after trimming, put the box into the shot blasting machine for shot blasting, spray 0.15-0.5mm steel shot in the shot blasting machine, shot blast the box for 3-5 minutes, and turn the box synchronously in the shot blasting machine during the shot blasting process; remove the oxide layer on the surface of the box by shot blasting, making the surface of the box denser and better looking.

[0084] Step 5: Machining: The box body after shot blasting is transported to the machining workshop for machining. In the machining workshop, the box body is further processed by drilling, cutting, etc., and the cutting fluid is used for cooling and lubrication during cutting.

[0085] Step 6. Cleaning: Move the machined box to the cleaning workshop and perform ultrasonic cleaning on the box. Ultrasonic cleaning of the box has high cleaning efficiency, good cleaning effect and good cleanliness.

[0086] Step 7: Packing and warehousing: Inspect the surface of the box after cleaning, then pack and warehousing.

[0087] The present invention is cleverly and reasonably designed, strictly controls the feed ratio of aluminum ingots and scrap in the smelting raw materials, and performs slag removal on the molten aluminum liquid, effectively reducing the impurity content of the aluminum liquid and ensuring the quality of subsequent products. During die-casting, the mold is temperature-controlled and vacuumed in advance, and the temperature control is used to ensure that the mold reaches a suitable temperature before the aluminum liquid is injected into the mold, thereby improving the quality and surface finish of the box. The vacuum treatment in the mold can realize high-speed filling and high-pressure solidification molding of the die-casting machine, effectively eliminating gas defects in the box, such as bubbles, pores and air gaps, and further improving the quality and surface finish of the box. Compared with the traditional battery pack that uses aluminum profile welding processing technology, the production process of this application can omit the welding process and greatly improve the airtightness qualification rate of the product.

[0088] The above are only specific embodiments of the present invention, but the technical features of the present invention are not limited thereto. Any simple changes, equivalent replacements or modifications made based on the present invention to achieve basically the same technical effects are all included in the protection scope of the present invention.

Claims

1. The fully automatic production process of battery pack box is characterized by: The steps include: Step 1: Smelting: Add the raw materials into the melting furnace to melt, and put the aluminum ingots and scraps into the melting furnace at a feed ratio of 7:3 to melt and form aluminum liquid; Step 2, die casting: an exhaust gas purification treatment system is arranged above the die casting machine, and the exhaust gas purification treatment system cover is arranged above the die casting machine, and the exhaust gas generated during the die casting process is collected and treated by the exhaust gas purification treatment system; Die casting includes the following steps: (1) Add the molten aluminum metal into the quantitative furnace for heat preservation. The quantitative pump in the quantitative furnace transports the aluminum metal into the die-casting machine material pipe through the heating chute according to the set value, and then transports it into the pressure chamber of the die-casting machine through the die-casting machine material pipe. Then, the aluminum metal is injected into the mold cavity after the mold is closed through the pressure chamber; (2) Before injecting the aluminum liquid into the mold cavity, the temperature of the mold is adjusted by a mold temperature controller, which includes an oil temperature controller and a water temperature controller. Both the oil temperature controller and the water temperature controller are connected to the mold pipeline through pipelines. The thermal oil delivery pump in the oil temperature controller delivers the thermal oil to the mold pipeline, and the pure water delivery pump in the water temperature controller delivers the heated pure water to the mold pipeline. The mold is temperature-controlled by the thermal oil and the heated pure water, and the mold temperature is monitored by a temperature detection imager until the mold temperature reaches the set temperature value; (3) Before the aluminum liquid is injected into the mold cavity, the mold is vacuumed by a vacuum machine; (4) Demolding: The pick-up robot takes out the die-cast box and puts it into the machine-side cooling station for cooling. The machine-side cooling station uses spraying or jetting to supply water, and the cooling water evenly wets the surface of the box to cool the surface of the box. Then, the spraying system is used to spray the surface of the movable mold and the fixed mold after the mold is opened. The spraying operation of the spraying system is as follows: a. The spraying system includes a release agent proportioning device, a water-gas distribution cabinet, a gas storage tank and a robot spray head assembly. The release agent proportioning device and the gas storage tank are connected to the water-gas distribution cabinet, the water-gas distribution cabinet is connected to the robot spray assembly, a flow meter is provided on the pipeline between the water-gas distribution cabinet and the robot spray assembly, and the robot spray head assembly includes a first spray robot and a second spray robot; b. The first spraying robot corresponds to the movable mold in the mold, and the second spraying robot corresponds to the fixed mold in the mold. The first spraying robot and the second spraying robot are both provided with spraying heads. The release agent proportioning device conveys the release agent to the water-gas distribution cabinet, and the gas storage tank conveys the gas to the water-gas distribution cabinet. The water-gas distribution cabinet distributes the release agent and gas to the first spraying robot and the second spraying robot, and then sprays them out from the spraying heads in the form of droplets to spray the surfaces of the movable mold and the fixed mold; c. Distribute the release agent and gas to the first spraying robot and the second spraying robot in the water and gas distribution cabinet, and control the flow rate through the flow meter; Before the picking robot takes out the box and puts it into the machine-side cooling station, it first performs a laser inspection on the box for integrity. The inspection process is as follows: a. The boxes that have passed the inspection enter the machine side cooling station for cooling, and then undergo edge trimming. After edge trimming, the subsequent processing steps are carried out in sequence; b. The unqualified boxes are cooled in the machine side cooling station, and then trimmed after cooling. After trimming, the unqualified boxes are sent to the unloading trolley by the manipulator; Step 3, trimming: the die-casting trimming machine is used to trim the boxes after demolding and cooling. The die-casting trimming machine uses a plasma beam to trim the boxes; Step 4, shot blasting: the box after trimming is polished, and the box is placed in the shot blasting machine for shot blasting. The shot blasting machine sprays 0.15-0.5mm steel shots, and the box is shot blasted for 3-5min. During the shot blasting process, the box is synchronously turned over in the shot blasting machine; Step 5, machining: the box after shot blasting is transported to the machining workshop for machining; Step 6, cleaning: the machined box is transported to the cleaning workshop, and the box is ultrasonically cleaned; Step 7, packaging and warehousing: the surface of the cleaned box is inspected and then packaged for warehousing.

2. The fully automatic production process for battery pack box according to claim 1, characterized in that: In the above step 1, before the metal aluminum liquid is transported to the capacity furnace, a slag remover is added to the metal aluminum liquid, stirred for 2-3 minutes, and then allowed to stand for 12-20 minutes, and then solid-liquid separation is performed to remove the solid slag, leaving the metal aluminum liquid after slag removal.

3. The fully automatic production process for battery pack box according to claim 2, characterized in that: The molten aluminum after slag removal is tested to ensure that the density equivalent range of the molten aluminum fluctuates within plus or minus three percent.

4. The fully automatic production process for battery pack box according to claim 1, characterized in that: The spray head comprises a liquid separation plate, an air blowing pipe and a nozzle, and the air blowing pipe and the nozzle are distributed on the liquid separation plate.

5. The fully automatic production process for battery pack box according to claim 1, characterized in that: In step (3) of the above step 2, the steps of vacuuming by the vacuum machine are as follows: a. The vacuum machine includes a front-stage vacuum pump and a vacuum tank. The front-stage vacuum pump is connected to the vacuum tank through a vacuum pipeline. A filter is provided at the inlet of the front-stage vacuum pump. A vacuum interface is connected to the vacuum pipeline. The vacuum interface is connected to the mold cavity through a vacuum channel. A pneumatic butterfly valve and a mechanical vacuum gauge are provided on the vacuum pipeline. A manual butterfly valve is provided on the vacuum interface. A vacuum sensor is provided on the vacuum tank. b. Open the pneumatic butterfly valve and start the fore vacuum pump. The fore vacuum pump evacuates the vacuum tank and measures the pressure value in the vacuum tank through the vacuum sensor. When the pressure value in the vacuum tank reaches the set value, close the pneumatic butterfly valve and the fore vacuum pump. The vacuum tank reaches a vacuum state and forms a negative pressure. During the process of the fore vacuum pump evacuating the vacuum tank, the air must be filtered by the filter before entering the fore vacuum pump. c. Open the manual butterfly valve, and the air in the mold cavity will diffuse into the vacuum tank along the vacuum channel, vacuum interface, and vacuum pipeline until the vacuum in the mold pipeline is lower than 3mbar and the vacuum in the mold cavity is lower than 40mbar. Then close the manual butterfly valve and the vacuum process stops.

6. The fully automatic production process for battery pack box according to claim 1, characterized in that: In step (1) of the above step 2, during the die-casting process, the casting pressure of the die-casting machine is 70-100 MPa.

7. The fully automatic production process for battery pack cases according to claim 1, characterized in that: In step (1) of the above step 2, the quantitative accuracy of the quantitative furnace fluctuates within plus or minus 1%, and the quantitative speed is 8 to 10 kg / s.

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