A rapid vacuum drying system for precision casting

Abstract

To solve the problems in the prior art, the application provides a rapid vacuum drying system for precision casting, which comprises a vacuum drying cavity, a vacuum pump and a control system. The vacuum pump performs vacuumizing treatment on the vacuum drying cavity. A drying rack is arranged in the vacuum drying cavity, and a to-be-dried ceramic shell is arranged on the drying rack to perform drying treatment. At least two groups of fans with different air directions are arranged around the drying rack in the vacuum drying cavity. The control system comprises a vacuum drying control module and a fan group control module. The vacuum drying control module controls vacuumizing and / or recovery of the chamber pressure of the vacuum drying cavity, and the fan group control module controls the start / stop and / or control parameters of all the fan groups, so that the drying time of each part of the to-be-dried ceramic shell tends to be consistent. The application can effectively balance the drying time of deep holes and surfaces and obtain optimal results.

Description

Technical Field

[0001] This invention relates to the field of precision casting technology, specifically to a rapid vacuum drying system for precision casting. Background Technology

[0002] Precision casting is a casting method relative to traditional casting processes, which can achieve relatively accurate shapes and high casting precision. The precision casting process is as follows: First, a wax model is made, which matches the size and shape of the product to be cast. Then, a ceramic shell is formed on the surface of the wax model. Subsequently, the ceramic shell is dewaxed (the wax model inside is melted and removed). Finally, metal material is poured into the dewaxed ceramic shell. After the metal material cools and solidifies, the ceramic shell is broken and removed, and the resulting casting is the desired product.

[0003] In the aforementioned process, the fabrication of the ceramic shell is crucial, as its quality determines the quality of the casting. Currently, the commonly used method for ceramic shell fabrication is the shell mold method, specifically the water-soluble silica sol shell-making method. This method involves using refractory materials to prepare different slurries and sands, layering the slurry and sand layer by layer onto the surface of the wax model to create a ceramic shell of the required thickness. Therefore, the ceramic shell can be structurally divided into a surface layer, a transition layer (two layers), a support layer (back layer), and a sealing layer. The surface layer, transition layer, and sealing layer are each a single layer, while the support layer typically has multiple layers.

[0004] Based on the concentration of the ceramic shell slurry during the preparation process, ceramic shells are generally classified into thick slurry ceramic shells and thin slurry ceramic shells. As the name suggests, thick slurry ceramic shells have a higher concentration of ceramic shell slurry. Compared to thin slurry ceramic shells, the main advantages of thick slurry ceramic shells are: 1. Each layer of ceramic shell is relatively thick and has high support strength. Therefore, fewer layers of thick slurry ceramic shell can achieve the same support strength as thin slurry ceramic shell, which would require more layers, thus reducing the complexity of the process.

[0005] 2. The ceramic shell surface layer has a high density, and the problem of casting penetration is rare.

[0006] However, the main reason why thin-slurry ceramic shells are still chosen in most cases when preparing ceramic shells using existing technologies is that thick-slurry ceramic shells have the following insurmountable problems: Although the moisture content of thick slurry ceramic shell is low, the resistance to the movement of water molecules is greater. Therefore, its drying time is even longer than that of thin slurry. When castings with deep holes are involved, it is difficult to make the drying time of different parts of the ceramic shell tend to be consistent. Often, when the ceramic shell in the deep hole is dried, the other parts of the ceramic shell may have already become over-dried, causing the ceramic shell to crack.

[0007] However, due to the limitation of single-layer thickness expansion in thin-film ceramic shells, when the breaking strength coefficient is low, it is necessary to increase the thickness of the ceramic shell by increasing the number of layers to provide sufficient support. This requires multiple slurry application processes, increasing the complexity of the process. The drying time of the ceramic shell increases with the number of layers, significantly reducing the production efficiency. Furthermore, when dealing with deep-hole castings, ensuring that the drying time of different parts of the thin-film ceramic shell is consistent and can be completed in a shorter time remains a technical challenge. Summary of the Invention

[0008] This invention addresses the problems of existing technologies by providing a rapid vacuum drying system for precision casting, comprising: a vacuum drying chamber, a vacuum pump, and a control system. The vacuum pump evacuates the vacuum drying chamber. A drying rack is installed inside the vacuum drying chamber, and the ceramic shell to be dried is placed on the drying rack for drying. At least two sets of fans with different airflow directions are arranged around the drying rack inside the vacuum drying chamber.

[0009] The control system includes a vacuum drying control module and a fan unit control module. The fan unit control module controls the start-up and / or control parameters of all fans, so that the drying time of each part of the ceramic shell to be dried tends to be consistent.

[0010] The vacuum drying chamber is equipped with a three-dimensional detection mechanism. The three-dimensional detection mechanism drives the scanning device to move along the X-axis, Y-axis, and Z-axis.

[0011] The scanning device includes at least one camera device. The camera device is used to acquire image data of the ceramic shell to be dried.

[0012] The control system includes a ceramic shell analysis module. This module acquires image data of the ceramic shell to be dried and performs model structure analysis to obtain the location, orientation, and depth of the deep holes in the ceramic shell, which is then sent to the fan unit control module. Based on the location, orientation, and depth of the deep holes in the ceramic shell, the fan unit control module performs fan unit control analysis and controls the start / stop and / or control parameters of each fan unit according to the analysis results.

[0013] Furthermore, the vacuum pump is connected to the vacuum drying chamber via a first connecting pipe, and a first electrically controlled switching valve is installed on the first connecting pipe. The vacuum drying chamber is connected to an air pipe, and a second electrically controlled valve is installed on the air pipe. The vacuum drying control module controls the opening and closing of the vacuum pump, the first electrically controlled switching valve, and the second electrically controlled valve.

[0014] Furthermore, the drying rack is detachably installed inside the vacuum drying chamber. The ceramic shell to be dried is detachably mounted on the drying rack.

[0015] Furthermore, the vacuum drying chamber has a first blower unit at the top of the drying rack, a second blower unit at the bottom of the drying rack, a third blower unit on the opening and closing door of the vacuum drying chamber along the cross-section of the drying rack, and a fourth blower unit and a fifth blower unit on both sides of the drying rack along the axial direction of the vacuum drying chamber.

[0016] Furthermore, an adjustable component is provided inside the vacuum drying chamber on the opposite side of the third blower unit. The adjustable component is either a condenser or a sixth blower unit.

[0017] Furthermore, the three-dimensional detection mechanism includes: two parallel X-axis guide rails horizontally arranged along the axial direction of the vacuum drying chamber and located on both sides of the drying rack; and a Y-axis guide rail horizontally arranged along the cross-section of the vacuum drying chamber. Each of the two X-axis guide rails is equipped with a first displacement device capable of displacement along the X-axis guide rail. The Y-axis guide rail is fixed between the two first displacement devices and is driven by the two first displacement devices to move along the X-axis guide rail. The Y-axis guide rail is equipped with a second displacement device capable of displacement along the Y-axis. The second displacement device is vertically equipped with an electrically controlled telescopic device that extends and retracts along the Z-axis. A scanning device is fixed to the telescopic end of the electrically controlled telescopic device via an electrically controlled pan-tilt unit. The first displacement device, the second displacement device, the electrically controlled telescopic device, and the electrically controlled pan-tilt unit are all signal-connected to the control system.

[0018] Furthermore, the control system includes a scanning device control module. The scanning device control module controls the movement of two first displacement devices, a second displacement device, an electrically controlled telescopic device, and an electrically controlled pan-tilt unit, so that the scanning device can perform omnidirectional imaging / scanning of the ceramic shell to be dried, obtaining images / scanning data of the ceramic shell.

[0019] Furthermore, the model structure analysis includes image analysis: First, obtain the outer contour model data, deep hole location data, and deep hole depth data of the ceramic shell to be dried.

[0020] Then, the acquired image data is compared with the outer contour model data to determine the spatial orientation of the ceramic shell to be dried suspended in the vacuum drying chamber.

[0021] Finally, the current position and orientation of the deep hole in the ceramic shell to be dried are determined based on the spatial orientation of the shell, and the position, orientation, and depth data of the deep hole are output.

[0022] Furthermore, the scanning device also includes a scanning distance measuring device. The scanning distance measuring device is used to measure the distance between the ceramic shell to be dried and the scanning device in real time.

[0023] The model structure analysis includes: Step 1.1 The scanning distance measuring device performs an all-around scan of the surface n of the ceramic shell to be dried along a preset line, and obtains the distance measurement data set G of all scanning points on surface n relative to the scanning distance measuring device. n .

[0024] Step 1.2 G of the ranging data set n Connect the endpoints to obtain the numerical surface m of the ceramic shell surface n to be dried.

[0025] Step 1.3 Combine the image data to perform graphic analysis on the digital surface m of the ceramic shell to be dried, and determine the basic surface, raised surface and groove surface of the digital surface m.

[0026] Step 1.4 Calculate the difference C between each measuring point within the groove surface and each measuring point on the adjacent basic surface of the groove. mk-b , where mk is the groove numbered k on the digital surface m, and b is a separate number for the measuring point inside the groove mk.

[0027] Step 1.5 Take C mk-b >K2 is a deep hole, take C mk-b >K3 is a through hole. Wherein, K2 is the preset deep hole judgment threshold, and K3 is the model width, model length, or model height corresponding to the surface n of the ceramic shell to be dried.

[0028] Step 1.6 Count the positions of all deep holes (m) on the digital surface of the ceramic shell to be dried (W). mc The depth H corresponding to each deep hole mc , where c is the natural number of the deep hole on the digital surface m.

[0029] Step 1.7 Repeat steps 1.1 to 1.6 until all deep holes on the surface of the ceramic shell to be dried can be scanned. mc Depth H mc Statistics completed. The orientation X of the deep hole is determined based on the surface n where the deep hole is located. mc .

[0030] Step 1.8 Output the locations W of all deep holes on the surface of the ceramic shell to be dried. mc Depth H mc Orientation X mc data.

[0031] Furthermore, the method for obtaining the basic surface, raised surface, and grooved surface described in step 1.3 includes: Step 1.3.1 Obtain the image data corresponding to the digital surface m of the ceramic shell to be dried, and obtain the image surface R by stitching the image data.

[0032] Step 1.3.2 Perform feature identification on the image surface R to obtain the feature region rn-m on the image surface R, where rn is the sequential number of the feature region in the digital surface m.

[0033] Step 1.3.3 Adjust the digital surface m to have the same orientation and similar size as the image surface R.

[0034] Step 1.3.4 Take the feature region rc-m with the largest continuous area as the basic surface, where rc-m belongs to rn-m.

[0035] Step 1.3.5 Obtain the distance measurement point data for each non-fundamental surface feature region. The distance measurement points of the feature region that are greater than the distance measurement points of the adjacent fundamental surface are called groove points, and the distance measurement points of the feature region that are less than the distance measurement points of the adjacent fundamental surface are called convex points.

[0036] Step 1.3.6 Using the feature area as the boundary, connect adjacent groove points and convex points to form groove surfaces and convex surfaces.

[0037] Furthermore, the three-dimensional detection mechanism is equipped with an electrically controlled telescopic device, and a scanning device is fixed to the telescopic end of the device via an electrically controlled pan-tilt unit. The pan-tilt unit includes: a fixed platform fixed to the telescopic device, and a rotating platform rotatably connected to and rotating relative to the fixed platform along a vertical axis. The rotating platform is rotatably connected to the fixed end of the second electrically controlled telescopic device via a reducer, and the reducer controls the second telescopic device to rotate along a horizontal axis. The scanning device is fixed to the telescopic end of the second electrically controlled telescopic device.

[0038] Furthermore, the model structure analysis also includes: Step 2.1 Based on the location of the deep hole, control the scanning ranging device to move to the location of the deep hole.

[0039] Step 2.2 By adjusting the orientation of the scanning ranging device relative to the deep hole, multiple deep hole depth measurement data are obtained.

[0040] Step 2.3 Correct the original deep hole depth data H using the deepest depth measurement data. m-c The corrected data H is obtained. m-c `.

[0041] Furthermore, the scanning device also includes an infrared temperature measuring device. The control system includes a drying process analysis module, which acquires the measurements from the infrared temperature measuring device to analyze the drying process and determine whether the ceramic shell to be dried has been completely dried.

[0042] The drying process analysis includes: periodically or continuously measuring the internal temperature T of the deep hole. The deep hole temperature T is measured. v - Curve Q of drying time t v When Qv When curve segments conforming to the preset curve pattern appear, it indicates that the drying of the ceramic shell is complete. Here, v represents the natural number of all the deep pores in the ceramic shell to be dried.

[0043] Furthermore, the preset curve pattern includes: the internal temperature T of the deep hole gradually decreases from the initial drying temperature T1 to temperature T2 with drying time, and then gradually increases to the drying ambient temperature T3 with drying time. When the temperature T of the deep hole of the ceramic shell to be dried goes through T1-T2-T3 and is maintained at the drying ambient temperature T3 for a preset time U, it is judged that drying is complete. The initial drying temperature T1 is 22-26℃, the temperature T2 is 5-7℃ lower than the initial drying temperature T1, and the drying ambient temperature T3 is 24±1℃.

[0044] Furthermore, when there are multiple ceramic shells to be dried in the same batch, the temperature of each deep hole of each ceramic shell is tested individually. When more than L% of the ceramic shells to be dried have been dried, the entire batch of ceramic shells is considered to be dried successfully. L% = (L g-d ) / (L 0-d ) 100%, of which L g-d L represents the number of ceramic shells to be dried after batch d has finished drying. 0-d This represents the total number of ceramic shells to be dried in batch d. The value of L% is: 100% ≥ L% ≥ E%. Here, E is the preset threshold for the minimum percentage of dried ceramic shells in batch d.

[0045] Furthermore, the wind turbine control analysis includes: For all fan units p with deep pores on the ceramic shell surface to be dried, the following method is adopted: Step 3.1 Obtain the total number of deep holes D0 on the surface of the ceramic shell to be dried facing the fan unit p. p p represents the fan unit number located on different sides of the vacuum drying chamber.

[0046] Step 3.2 Calculate k S-p %=D p / D0 100%, the k S-p % represents the control parameter of the wind turbine unit p.

[0047] Step 3.3 Repeat steps 3.1 to 3.2 until you obtain k for all wind turbine units. S-p %.

[0048] For all fan units p whose ceramic shell surfaces to be dried do not have deep pores, the following method is adopted: Calculate k F-p %=[1-D0 / (D0+1)] 100%, the k F-p % represents the control parameter of the wind turbine unit p.

[0049] The wind turbine control module will obtain k from all wind turbines. S-p % and k F-p % is sent to the corresponding wind turbine unit p to control wind turbine unit p to operate at full load k S-p % or k F-p % to run.

[0050] Furthermore, the wind turbine control analysis includes: For all fan units p with deep pores on the ceramic shell surface to be dried, the following method is adopted: Step 4.1 Obtain the total number of deep holes D0 on the surface of the ceramic shell to be dried facing the fan unit p. p p represents the fan unit number located on different sides of the vacuum drying chamber.

[0051] Step 4.2 Based on D0 and D p The quantity, k, is obtained from the self-control parameter database. S-p %. The k S-p % represents the control parameter of the wind turbine unit p.

[0052] Step 4.3 Repeat steps 4.1 to 4.2 until you obtain k for all wind turbine units. S-p %.

[0053] For all fan units p whose ceramic shell surfaces to be dried do not have deep pores, the following method is adopted: Based on the total number of deep pores D0 in the ceramic shell to be dried, k is obtained from the self-control parameter database. F-p %. The k F-p % represents the control parameter of the wind turbine unit p.

[0054] The wind turbine control module will obtain k from all wind turbines. S-p % and k F-p % is sent to the corresponding wind turbine unit p to control wind turbine unit p to operate at full load k S-p % or k F-p % to run.

[0055] Furthermore, k is entered into the control parameter database. S-p % and k F-p The methods include: Step 5.1 Simulate the same fan unit position and orientation as the target vacuum drying chamber in the simulation equipment.

[0056] Step 5.2 Preset drying training for different pore distributions of the ceramic shells to be dried, and determine the control parameter k of each fan unit p relative to full load for the optimal drying time under each pore distribution. S-p % and k F-p The percentage refers to the distribution of deep holes, including their orientation and number. The optimal drying time is the shortest time required for the deep holes and surface layer of the ceramic shell to dry to dry synchronously.

[0057] Step 5.3 Repeat step 5.2 until the deep hole distribution under normal conditions is trained, and construct D0-D p -k S-p % - k F-p The deep hole-control parameter relationship group is set and stored in the control parameter database.

[0058] Furthermore, at least two fans are arranged and installed within the fan unit. The fan unit control module performs synchronous control or individual control of the fans within each fan unit.

[0059] Furthermore, the wind turbine control analysis also includes: Step 6.1 Construct a three-dimensional coordinate system based on the scanning starting point preset by the scanning device.

[0060] Step 6.2 Record the three-dimensional coordinate points in space during the displacement of the scanning device, and mark the three-dimensional coordinate points of the deep hole position, orientation and depth of the obtained ceramic shell to be dried during the model structure analysis.

[0061] Step 6.3 Obtain the coordinate system range U covered by the blowing direction of each fan in the fan unit p. p-e , where e is the natural number of the fan in fan unit p.

[0062] Step 6.4 Statistical analysis of U p-e Number of deep holes D within the coverage area up-e And the number of deep holes D within the overall coverage area of ​​the wind turbine unit p. up .

[0063] Step 6.5 Calculate k up-e %=(D up-e / D up ) k S-p %.

[0064] The wind turbine control module will obtain the k values ​​of each wind turbine within wind turbine unit p. up-e % is sent to the corresponding wind turbine to control the corresponding wind turbine to operate at full load k up-e % to run. For D up-e The fan corresponding to =0 operates at the lowest power.

[0065] Furthermore, the wind turbine control analysis includes: Step 7.1 Construct a three-dimensional coordinate system based on the scanning starting point preset by the scanning device.

[0066] Step 7.2 Record the three-dimensional coordinate points in space during the displacement of the scanning device, and mark the three-dimensional coordinate points of the deep hole position, orientation and depth of the obtained ceramic shell to be dried during the model structure analysis.

[0067] Step 7.3 Obtain the coordinate system range U covered by the blowing direction of each fan in the fan unit p. p-e , where e is the natural number of the fan in fan unit p.

[0068] Step 7.4 Statistical analysis of U p-e Number of deep holes D within the coverage area up-e And the number of deep holes D within the overall coverage area of ​​the wind turbine unit p. up .

[0069] Step 7.5 According to D up and D up-e Retrieve the corresponding fan's k value from the control parameter database. up-e %, the k up-e % represents the control parameter of fan number e within fan unit p.

[0070] The wind turbine control module will obtain the k values ​​of each wind turbine within wind turbine unit p. up-e % is sent to the corresponding wind turbine to control the corresponding wind turbine to operate at full load k up-e % to run.

[0071] Furthermore, k is entered into the control parameter database. up-e The methods include: Step 8.1 Simulate the same fan unit position and orientation as the target vacuum drying chamber in the simulation equipment.

[0072] Step 8.2 Preset drying training for different pore distributions of the ceramic shells to be dried, and determine the operating ratio k of each fan in each fan group p at relative full load corresponding to the optimal drying time under each pore distribution. up-e The percentage refers to the distribution of deep holes, including their orientation and number. The optimal drying time is the shortest time required for the deep holes and surface layer of the ceramic shell to dry to dry synchronously.

[0073] Step 8.3 Repeat step 8.2 until the deep hole distribution under normal conditions is trained, and construct D. up - D up-e -k up-e The deep hole-control parameter relationship group is set and stored in the control parameter database.

[0074] Furthermore, the rapid vacuum drying system includes: a first data transmission module, a local database module, and a remote system module.

[0075] The first data transmission module is connected to the remote system module via a signal line or a wireless network.

[0076] The local database module serves as a control parameter database to store relevant deep hole-control parameter relationship sets and operation result data.

[0077] The remote system module collects the deep-hole-control parameter relationship groups and operating result data of each rapid vacuum drying system through the first data transmission module, and selects the deep-hole-control parameter relationship group corresponding to the best operating result from the same deep-hole relationship. Based on authorization and / or command and / or automatic synchronization, the deep-hole-control parameter relationship group corresponding to the best operating result is centralized through the remote system module and then synchronized to the local database module of each rapid vacuum drying system through the first data transmission module, or directly synchronized to the local database module of each rapid vacuum drying system through the first data transmission module.

[0078] When the rapid vacuum drying system retrieves the deep hole-control parameter relationship group from the local database module, if a new optimal deep hole-control parameter relationship group exists, it will retrieve that new optimal deep hole-control parameter relationship group first.

[0079] Furthermore, the rapid vacuum drying system also includes a second data transmission module.

[0080] The remote system module is connected to the control system of the rapid vacuum drying system via a signal line connection or a wireless network connection through the second data transmission module, so as to send remote control commands to the control system and / or obtain control commands issued by the control system and / or obtain the operating status parameters of various electrical control devices in the rapid vacuum drying system.

[0081] The execution priority of remote control commands issued by the remote system module is higher than that of control commands issued by the control system.

[0082] Furthermore, the drying rack includes a ceramic shell hanger for suspending the ceramic shells to be dried. The ceramic shell hanger has several hook slots. The ceramic shells to be dried are hooked into the hook slots by hooks. A hanger support plate is fixed to the bottom of the ceramic shell hanger. Several rollers that can slide along a guide rail are provided at the bottom of the hanger support plate. The guide rail is fixed to the bottom surface inside the vacuum drying chamber.

[0083] Furthermore, a limiting block is provided on the guide rail on the side away from the opening and closing door of the vacuum drying chamber.

[0084] Furthermore, the scanning device includes a thermal imager. The method for making the drying time of all parts of the ceramic shell to be dried tend to be consistent includes: Step 9.1 During the drying process of the ceramic shell to be dried, the thermal imager, along with the scanning device, takes real-time thermal images of the ceramic shell to be dried and sends them to the control system.

[0085] Step 9.2 Based on the heat distribution in the thermal imaging image, when the drying time exceeds the preset first drying time, the control system determines whether there is a region T where the high and low temperature difference exceeds the preset temperature difference threshold. If region T exists, the following determination and operation are performed: When the temperature in the low-temperature zone of region T is lower than the preset low-temperature threshold, the operating power of the corresponding fan unit in region T is reduced.

[0086] When the temperature in the high-temperature zone of region T exceeds the preset high-temperature threshold, the operating power of the corresponding fan unit in region T is increased.

[0087] When the time of existence of region T exceeds the preset time threshold, and the temperature of the low-temperature region of region T is higher than the preset low-temperature threshold and the temperature of the high-temperature region of region T is lower than the preset high-temperature threshold, the operating power of the wind turbine unit corresponding to region T is increased.

[0088] Furthermore, the preset low temperature threshold is 12-15℃, the preset high temperature threshold is 26-28℃, the preset first drying time is 1-3 minutes, and the preset time threshold is 30-60 seconds.

[0089] Furthermore, the rapid vacuum drying system also includes a vacuum tank. One end of the vacuum tank is connected to a vacuum pump via a second connecting pipe, and a third electrically controlled valve is installed on the second connecting pipe. The other end of the vacuum tank is connected to a vacuum drying chamber via a third connecting pipe, and a fourth electrically controlled valve is installed on the third connecting pipe.

[0090] This invention has at least one of the following beneficial effects: 1. This invention uses automatic analysis and control to make the drying time of different parts of the ceramic shell more consistent. Especially when dealing with deep-pore structures where uniform drying is difficult, it can effectively balance the drying time of deep pores and the surface and obtain the optimal result.

[0091] 2. This invention has remote control and remote sharing capabilities, which can synchronize the best fan control method to the entire vacuum drying system, significantly reducing the trial and error costs for enterprises when drying various types of ceramic shells and improving enterprise efficiency. Attached Figure Description

[0092] Figure 1 The diagram shown is a structural schematic of the rapid vacuum drying system of the present invention. Figure 2 The diagram shown is a schematic diagram of a portion of the internal structure of the vacuum drying chamber of this invention; Figure 3 The diagram shown is a partial structural diagram of the three-dimensional detection mechanism of the present invention; Figure 4 The diagram shown is a schematic diagram of the Z-axis portion of the three-dimensional detection mechanism of the present invention. Figure 5 The diagram shown is a schematic of the electronically controlled gimbal structure of the present invention. Figure 6 The diagram shown is a schematic representation of the scanning device of the present invention. Figure 7 The diagram shown is an exemplary ceramic shell structure. Figure 8 The image shows the scanning device of the present invention. Figure 7 A schematic diagram showing the scanning of the ceramic shell; Figure 9 The figure shown is a schematic diagram of the temperature-time curve for determining whether drying is complete according to the preset curve pattern of the present invention. Figure 10 The diagram shown is another exemplary ceramic shell structure; In the diagram: 1. Vacuum drying chamber; 101. First blower unit; 102. Second blower unit; 103. Third blower unit; 104. Fourth blower unit; 105. Fifth blower unit; 106. Air pipe; 107. Second electrically controlled valve; 108. Adjustable component; 2. Three-dimensional detection mechanism; 201. X-axis guide rail; 202. Y-axis guide rail; 203. First displacement device; 204. Second displacement device; 205. Electrically controlled telescopic device; 206. Electrically controlled pan-tilt unit; 2061. Fixed platform; 2062. Rotating platform; 2063. Reduction gear. 1. Machine; 2064. Second electrically controlled telescopic device; 207. Scanning device; 2071. Camera device; 2072. Thermal imager; 2073. Scanning distance measuring device; 2074. Infrared temperature measuring device; 3. Drying rack; 301. Guide rail; 302. Hanging bracket plate; 303. Roller; 304. Ceramic shell hanging rack; 305. Hook hanging groove; 4. Ceramic shell to be dried; 401. Deep hole; 402. Handling part; 5. Vacuum tank; 6. Fourth electrically controlled valve; 7. Third connecting pipe; 8. Vacuum pump; 9. Third electrically controlled valve; 10. First electrically controlled switch valve; 11. Hook. Detailed Implementation

[0093] The invention will now be described in further detail with reference to the accompanying drawings. It is important to note that these descriptions are exemplary only and are not intended to limit the scope of the invention. Furthermore, descriptions of well-known structures and techniques are omitted in the following description to avoid unnecessarily obscuring the concept of the invention.

[0094] This invention provides an exemplary rapid vacuum drying system for precision casting, comprising: a vacuum drying chamber 1, a vacuum pump 8, and a control system. The vacuum pump 8 evacuates the vacuum drying chamber 1. A drying rack 3 is provided inside the vacuum drying chamber 1, and the ceramic shell 4 to be dried is placed on the drying rack 3 for drying. At least two sets of fans with different airflow directions are provided around the drying rack 3 inside the vacuum drying chamber 1.

[0095] The control system includes a vacuum drying control module and a fan unit control module. The fan unit control module controls the start and stop of all fan units and the control parameters during the operation of the fan units. By controlling at least two sets of fan units with different airflow directions through the fan unit control module, the drying time of each part of the ceramic shell to be dried tends to be consistent.

[0096] The vacuum drying chamber 1 is equipped with a three-dimensional detection mechanism 2. The three-dimensional detection mechanism 2 drives the scanning device 207 to move along the X-axis, Y-axis, and Z-axis. As needed, the three-dimensional detection mechanism 2 can be a displacement system with three degrees of freedom (X, Y, and Z), or it can be a collection system composed of displacement systems with at least one degree of freedom set in the X-axis, Y-axis, and Z-axis respectively.

[0097] The scanning device 207 includes a camera device 2071. The camera device 2071 is used to acquire image data of the ceramic shell 4 to be dried.

[0098] The control system includes a ceramic shell analysis module. This module acquires image data of the ceramic shell 4 to be dried and performs model structure analysis to obtain the location, orientation, and depth of the deep holes in the ceramic shell 4, which is then sent to the fan unit control module. Based on the location, orientation, and depth of the deep holes in the ceramic shell 4, the fan unit control module performs fan unit control analysis and controls the start / stop and / or control parameters of each fan unit according to the analysis results.

[0099] Existing vacuum drying systems typically use fixed-speed fan units. To achieve uniform drying, existing technologies, such as the applicant's prior patent CN 201610416881.4, employ two sets of fans operating in opposite directions and a rotating ceramic shell device. This allows the ceramic shell to continuously rotate and receive airflow during the drying process, thus improving the uniformity of the drying process. However, this method has the following drawbacks: 1. When drying complex components with deep holes, the problem of relatively uniform drying time between deep holes and other parts cannot be overcome. That is, when drying complex components with deep holes, the ceramic shell of the deep hole part may have already been over-dried when it is completely dried.

[0100] 2. The ceramic shell has a certain centrifugal force during rotation, which can easily cause the sand inside the ceramic shell to shift centrifugally, especially when the viscosity of the slurry is low.

[0101] 3. The ceramic shell needs to be rotated continuously during the drying process, which introduces the possibility of relative slippage of the ceramic shell to be dried. This could lead to the ceramic shell colliding with or slipping off the turntable, causing damage to the ceramic shell.

[0102] The rapid vacuum drying system for precision casting of this invention firstly uses image data analysis to quickly determine the basic structure of the ceramic shell, including the presence, location, and orientation of deep holes. This allows for the selection of the fan unit facing the deep holes, enabling appropriate fan operation ratio control. Secondly, the fan unit control module can control the fan units inside the vacuum drying chamber 1, providing different lateral wind intensities to vary the degree of airflow on different parts of the ceramic shell. The wind force is stronger on the windward side of the ceramic shell containing deep holes, facilitating rapid evaporation of moisture from the deep holes, while the wind force is weaker on the windward side of the ceramic shell without deep holes, preventing that part of the ceramic shell from drying too quickly. This ensures that the drying time for all parts of the ceramic shell tends to be consistent.

[0103] Analyzing image data can relatively quickly determine the basic structure of the ceramic shell, as well as the presence, location, and orientation of deep holes. This allows for the identification of fan units facing the deep holes, enabling appropriate fan operating ratio control.

[0104] This invention provides an exemplary connection structure between a vacuum pump 8 and a vacuum drying chamber 1, specifically including: the vacuum pump 8 is connected to the vacuum drying chamber 1 via a first connecting pipe, and a first electrically controlled switching valve 10 is provided on the first connecting pipe. The vacuum drying chamber 1 is connected to an air pipe 106, and a second electrically controlled valve 107 is provided on the air pipe 106. The vacuum drying control module controls the opening and closing of the vacuum pump 8, the first electrically controlled switching valve 10, and the second electrically controlled valve 107.

[0105] This invention provides an exemplary method for installing a drying rack 3 and a ceramic shell 4 to be dried, comprising: the drying rack 3 being detachably installed inside a vacuum drying chamber 1; and the ceramic shell 4 to be dried being detachably mounted on the drying rack 3.

[0106] Due to the limited internal space of the vacuum drying chamber 1 under conventional settings, it is very inconvenient to install or place the ceramic shell 4 to be dried inside the vacuum drying chamber 1. By making the drying rack 3 detachable, the ceramic shell 4 to be dried can be installed or placed on the drying rack 3 in an open or easily accessible location outside the vacuum drying chamber 1, and then the drying rack 3 with the ceramic shell 4 installed or placed can be installed into the vacuum drying chamber 1. This effectively overcomes the inconvenience of installing or placing the ceramic shell 4 to be dried inside the vacuum drying chamber 1.

[0107] This invention provides an exemplary configuration for a wind turbine unit, specifically as follows: Figure 1 and Figure 3 As shown: Inside the vacuum drying chamber 1, a first blower unit 101 is provided at the top of the drying rack 3, a second blower unit 102 is provided at the bottom of the drying rack 3, a third blower unit 103 is provided on the opening and closing door of the vacuum drying chamber 1 along the cross section of the drying rack 3, and a fourth blower unit 104 and a fifth blower unit 105 are provided on both sides of the drying rack 3 along the axial direction of the vacuum drying chamber 1, respectively.

[0108] The present invention provides an example of an additional component, such as... Figure 1 As shown: Inside the vacuum drying chamber 1, an adjustable component 108 is provided on the opposite side of the third blower unit 103. The adjustable component 108 is either a condenser or a sixth blower unit.

[0109] This invention provides an exemplary three-dimensional detection mechanism 2, comprising: two parallel X-axis guide rails 201 horizontally arranged along the axial direction of a vacuum drying chamber 1 and located on opposite sides of a drying rack 3; and a Y-axis guide rail 202 horizontally arranged along the cross-section of the vacuum drying chamber 1. Each of the two X-axis guide rails 201 is provided with a first displacement device 203 capable of displacement along the X-axis guide rail 201. The Y-axis guide rail 202 is fixed between the two first displacement devices 203 and is driven by the two first displacement devices 203 to move along the X-axis guide rail 201. The Y-axis guide rail 202 is provided with a second displacement device 204 capable of displacement along the Y-axis guide rail 202. The second displacement device 204 is provided with an electrically controlled telescopic device 205 that extends and retracts along the Z-axis direction in the vertical direction. A scanning device 207 is fixed to the telescopic end of the electrically controlled telescopic device 205 via an electrically controlled pan-tilt unit 206. The first displacement device 203, the second displacement device 204, the electrically controlled telescopic device 205, and the electrically controlled pan-tilt unit 206 are respectively connected to a control system signal.

[0110] The scanning device control module can control the three-dimensional detection mechanism of the present invention to drive the scanning device 207 to move in three dimensions: X-axis, Y-axis and Z-axis, so as to perform a full-range scan of the front, back, left, right and top of the ceramic shell 4 to be dried, and to perform a side scan of the bottom, so as to obtain the main structure image of the ceramic shell 4 to be dried, thereby more accurately determining the position and orientation of the deep hole of the ceramic shell 4 to be dried.

[0111] This invention provides an exemplary control system, which includes a scanning device control module. The scanning device control module controls the movement of two first displacement devices 203, a second displacement device 204, an electrically controlled telescopic device 205, and an electrically controlled pan-tilt unit 206, so that the scanning device 207 performs omnidirectional imaging / scanning of the ceramic shell 4 to be dried, obtaining images / scanning data of the ceramic shell 4 to be dried.

[0112] This invention provides an exemplary method for model structure analysis, specifically including image analysis: First, obtain the outer contour model data, deep hole location data, and deep hole depth data of the ceramic shell 4 to be dried.

[0113] Then, the acquired image data is compared with the outer contour model data to determine the spatial orientation of the ceramic shell 4 to be dried suspended in the vacuum drying chamber 1.

[0114] Finally, the current position and orientation of the deep hole in the ceramic shell 4 to be dried are determined based on the spatial orientation of the ceramic shell 4 to be dried, and the current position, orientation and depth data of the deep hole in the ceramic shell 4 to be dried are output.

[0115] Due to the rapid development of digital technology in recent years, it has become possible to design the ceramic shell to be dried through digital modeling. The ceramic shell to be dried obtained by digital model design has detailed structural data. Therefore, this invention compares the image data of the ceramic shell to be dried in the actual environment with the digital model, thereby quickly determining the position and orientation of the deep hole in the ceramic shell through the image data of the ceramic shell to be dried, and then obtaining the depth of the corresponding deep hole from the digital model. Thus, the position, orientation and depth data of the deep hole of the ceramic shell 4 to be dried can be obtained.

[0116] The present invention provides, by way of example, a scanning device 207, such as Figure 6 As shown, the scanning device 207 also includes a scanning distance measuring device 2073. The scanning distance measuring device 2073 is used to measure the distance between the ceramic shell 4 to be dried and the scanning device 207 in real time.

[0117] This invention provides an exemplary method for model structure analysis, comprising: Step 1.1 The scanning distance measuring device 2073 performs an all-around scan of the surface n of the ceramic shell 4 to be dried according to a preset line, and obtains the distance measurement data set G of all scanning points on the surface n relative to the scanning distance measuring device 2073. n .

[0118] Step 1.2 G of the ranging data set n Connect the end points to obtain the digital surface m of the surface n of the ceramic shell 4 to be dried.

[0119] Step 1.3 Combine the image data to perform graphic analysis on the digital surface m of the ceramic shell 4 to be dried, and determine the basic surface, raised surface and groove surface of the digital surface m.

[0120] Step 1.4 Calculate the difference C between each measuring point within the groove surface and each measuring point on the adjacent basic surface of the groove. mk-b , where mk is the groove numbered k on the digital surface m, and b is a separate number for the measuring point inside the groove mk.

[0121] Step 1.5 Take C mk-b >K2 is a deep hole, take C mk-b >K3 is a through hole. Among them, K2 is the preset deep hole judgment threshold, and K3 is the model width, model length or model height corresponding to the surface n of the ceramic shell 4 to be dried.

[0122] Step 1.6 Count the positions W of all deep holes on the digital surface m of the ceramic shell to be dried. mc The depth H corresponding to each deep hole mc , where c is the natural number of the deep hole on the digital surface m.

[0123] Step 1.7 Repeat steps 1.1 to 1.6 until all deep holes W on the surface of the ceramic shell 4 to be dried can be scanned. mc Depth H mc Statistics completed. The orientation X of the deep hole is determined based on the surface n where the deep hole is located. mc .

[0124] Step 1.8 Output the location W of all deep holes on the surface of the ceramic shell 4 to be dried. mc Depth H mc Orientation X mc data.

[0125] This invention provides an exemplary method for obtaining the basic surface, raised surface, and grooved surface mentioned in step 1.3, comprising: Step 1.3.1 Obtain the image data corresponding to the digital surface m of the ceramic shell 4 to be dried, and obtain the image surface R by stitching the image data.

[0126] Step 1.3.2 Perform feature identification on the image surface R to obtain the feature region rn-m on the image surface R, where rn is the sequential number of the feature region in the digital surface m.

[0127] Step 1.3.3 Adjust the digital surface m to have the same orientation and similar size as the image surface R.

[0128] Step 1.3.4 Take the feature region rc-m with the largest continuous area as the basic surface, where rc-m belongs to rn-m.

[0129] Step 1.3.5 Obtain the distance measurement point data for each non-fundamental surface feature region. The distance measurement points of the feature region that are greater than the distance measurement points of the adjacent fundamental surface are called groove points, and the distance measurement points of the feature region that are less than the distance measurement points of the adjacent fundamental surface are called convex points.

[0130] Step 1.3.6 Using the feature area as the boundary, connect adjacent groove points and convex points to form groove surfaces and convex surfaces.

[0131] like Figure 7The image shows a ceramic shell 4 containing a deep hole 401 that needs to be dried. Taking the left-facing front view (n=1) of the six front views of the ceramic shell 4 as an example, the above method is as follows: Step 1.1 The scanning distance measuring device 2073 performs an all-round scan of the surface n=1 of the ceramic shell 4 to be dried according to a preset line, and obtains the distance measurement data set G1 of all scanning points on the surface n=1 relative to the scanning distance measuring device 2073.

[0132] Step 1.2 as follows Figure 8 As shown, by connecting the end points of the ranging data set G1, we can obtain the digital surface m=1 of the surface n=1 of the ceramic shell 4 to be dried.

[0133] Step 1.3 Combine the image data to perform graphic analysis on the digital surface m=1 of the ceramic shell 4 to be dried, and determine the basic surface, raised surface and groove surface of the digital surface m=1.

[0134] Step 1.4 Calculate the difference C between each measuring point within the groove surface and each measuring point on the adjacent basic surface of the groove. mk-b Where mk is the groove numbered k on the digital surface m, and b is a separate number for the distance measuring point within groove mk. Since there are two grooves k=1 and k=2 at position m=1 on the digital surface, and the distance measuring point within k=1 includes five points from b=8 to b=12, C needs to be calculated. mk-b =C 11-8 =| (L 11-8 )-(L 11-13 ) |,C mk-b =C 11-9 =| (L 11-9 )-(L 11-13 ) |,C mk-b =C 11-10 =| (L 11-10 )-(L 11-13 ) |,C mk-b =C 11-11 =| (L 11-11 )-(L 11-13 ) |,C mk-b =C 11-12 =| (L 11-12 )-(L 11-13 The internal ranging points of k=2 include the four ranging points from b=18 to b=21, therefore C needs to be calculated. mk-b =C 11-18 =| (L 11-18 )-(L 11-13 ) |,C mk-b =C 11-19 =| (L 11-19 )-(L 11-13 ) |,Cmk-b =C 11-20 =| (L 11-20 )-(L 11-13 ) |,C mk-b =C11-21=| (L 11-21 )-(L 11-13 ) |.

[0135] Step 1.5 Take C mk-b >K2 is a deep hole, take C mk-b >K3 is a through hole. Wherein, K2 is a preset deep hole judgment threshold, and K3 is the model width, model length, or model height corresponding to surface n of the ceramic shell 4 to be dried. For example, C mk-b =C 11-10 >K2, therefore the groove at m=1 on the digital surface with k=1 is a deep hole.

[0136] Step 1.6 Count the positions W of all deep holes on the digital surface m=1 of the ceramic shell to be dried. mc =W 11 The depth H corresponding to each deep hole mc =H 11 Where c=1 is the natural number of the deep hole m=1 on the digital surface. Where W mc =W 11 The positions are the locations corresponding to ranging points 8 to 12, and the depth H corresponds to the deep hole. mc =H 11 C mk-b =C 11-10 The calculated value.

[0137] Step 1.7 Repeat steps 1.1 to 1.6 until all deep holes W on the surface of the ceramic shell 4 to be dried can be scanned. mc Depth H mc Statistics completed. The orientation X of the deep hole is determined based on the surface n where the deep hole is located. mc .

[0138] Step 1.8 Output the location W of all deep holes on the surface of the ceramic shell 4 to be dried. mc Depth H mc Orientation X mc data.

[0139] In existing technologies, not all ceramic shells 4 to be dried are obtained using digital model design, or the digital models of the ceramic shells 4 obtained using digital model design are incompatible with the rapid vacuum drying system. In such cases, the rapid vacuum drying system cannot determine whether the shadows in the image data are deep holes using the digital model, nor can it determine the depth of the deep holes using the image data. Using the method described above in this invention, the location W of all deep holes on the surface of the ceramic shell 4 to be dried can be confirmed automatically through scanning and analysis.mc Depth H mc Orientation X mc Data. This allows the rapid vacuum drying system to obtain the location W of all deep pores on the surface of the ceramic shell 4 to be dried. mc Depth H mc Orientation X mc The data is used for wind turbine control analysis.

[0140] This invention provides an exemplary three-dimensional detection mechanism 2, which is equipped with an electrically controlled telescopic device 205. A scanning device 207 is fixed to the telescopic end of the electrically controlled telescopic device 205 via an electrically controlled pan-tilt unit 206. The electrically controlled pan-tilt unit 206 includes: a fixed platform 2061 fixed to the electrically controlled telescopic device 205, and a rotating platform 2062 rotatably connected to the fixed platform 2061 and rotating relative to the fixed platform 2061 along a vertical axis. The rotating platform 2062 is rotatably connected to the fixed end of a second electrically controlled telescopic device 2064 via a reducer 2063, and the reducer 2063 controls the second electrically controlled telescopic device 2064 to rotate along a horizontal axis. The scanning device 207 is fixed to the telescopic end of the second electrically controlled telescopic device 2064.

[0141] It is difficult to scan the bottom of the ceramic shell 4 to be dried using a conventional gimbal. Therefore, the present invention improves the gimbal structure. On the one hand, the scanning device 207 can scan the bottom of the ceramic shell 4 to be dried by means of the second electronically controlled telescopic device 2064. On the other hand, the rotation direction of the scanning device 207 can be changed by means of the reducer 2063, increasing the degree of freedom of scanning motion, so that the scanning device 207 can adapt to scanning more complex ceramic shells 4 to be dried.

[0142] This invention provides an exemplary model structure analysis method, which, based on the above-described model structure analysis, further includes: Step 2.1 Based on the location of the deep hole, control the scanning ranging device 2073 to move to the location of the deep hole.

[0143] Step 2.2 By adjusting the orientation of the scanning ranging device 2073 relative to the deep hole, multiple deep hole depth measurement data are obtained.

[0144] Step 2.3 Correct the original deep hole depth data H using the deepest depth measurement data. m-c The corrected data H is obtained. m-c `.

[0145] When designing the ceramic shell 4 to be dried, the deep hole structure is generally designed on the axis of the model, so that the deep holes of the ceramic shell are distributed along the axis. In this way, during the scanning and ranging process, the ranging laser can penetrate into the deep hole to measure the distance data of the deep hole, thereby obtaining the depth of the deep hole. However, in actual work, not all the deep holes of the ceramic shell are designed along the axis, and not all the ceramic shells 4 to be dried are placed upright or hooked during drying. Therefore, the orientation of the deep hole will be deflected relative to the running axis of the scanning device 207. At this time, the laser emitted by the scanning and ranging device 2073 cannot penetrate into the deep hole, and the measured depth of the deep hole will be inaccurate, thus affecting the accuracy of the wind turbine control analysis. This results in a large difference between the actual drying speed of the deep hole part of the ceramic shell 4 to be dried and the designed drying speed, affecting the uniformity of drying of various parts of the ceramic shell 4 to be dried.

[0146] By employing the model structure analysis method supplemented by this invention, at the deep hole location, by adjusting the orientation of the scanning ranging device 2073 relative to the deep hole, the scanning ranging device 2073 can obtain multiple ranging data points with different orientations relative to the deep hole. These data points include ranging data points where the orientation of the scanning ranging device 2073 is consistent with or similar to the hole axis of the deep hole. This ranging data has a high degree of consistency or similarity with the depth of the deep hole, which can significantly improve the accuracy of the fan unit control analysis and significantly reduce the difference between the actual drying rate and the designed drying rate of the deep hole portion of the ceramic shell 4 to be dried.

[0147] The present invention provides, by way of example, a scanning device 207, such as Figure 6 As shown, the scanning device 207 described above also includes an infrared temperature measuring device 2074. The control system includes a drying process analysis module, which acquires the measurements from the infrared temperature measuring device 2074 to analyze the drying process and determine whether the ceramic shell 4 to be dried has been completely dried.

[0148] This invention provides an exemplary method for analyzing a drying process, including: periodically or continuously measuring the internal temperature T of a deep borehole. The deep borehole temperature T is measured. v - Curve Q of drying time t v When Q v When curve segments conforming to the preset curve pattern appear, it indicates that the drying of the ceramic shell 4 is complete. Here, v represents the natural number of all the deep pores in the ceramic shell 4.

[0149] This invention provides, by way of example, a preset curve pattern, such as... Figure 9As shown, the process includes: the internal temperature T of the deep hole gradually decreases from the initial drying temperature T1 to temperature T2 over time, and then gradually increases to the ambient drying temperature T3 over time. When the temperature T of the deep hole of the ceramic shell 4 to be dried experiences T1-T2-T3 and remains at the ambient drying temperature T3 for a preset time U, the drying is considered complete. The initial drying temperature T1 is 22-26℃, the temperature T2 is 5-7℃ lower than the initial drying temperature T1, and the ambient drying temperature T3 is 24±1℃.

[0150] Existing technologies primarily rely on experience or multiple tests to determine the drying completion of the ceramic shell 4 under specific drying conditions. Once the required drying time is reached, the drying is considered complete. However, this method is ineffective when dealing with multiple batches of varying ceramic shells 4. Since the structures of each batch are inconsistent, the drying time needs to be adjusted accordingly, necessitating advance drying time testing, which significantly impacts overall drying efficiency.

[0151] Through research, the applicant discovered that during the drying process of the ceramic shell 4, moisture evaporation is an endothermic process. In the initial stage of drying, due to the high moisture content in the ceramic shell slurry, a large amount of moisture evaporates, causing a significant drop in the temperature of the ceramic shell. As the moisture evaporates to a certain extent, the evaporation rate decreases due to the reduced moisture content in the ceramic shell slurry, and the temperature of the ceramic shell gradually approaches the ambient drying temperature. When the temperature of the ceramic shell is maintained at the ambient drying temperature, it indicates that almost no moisture has evaporated, signifying that drying is complete. Therefore, the method of determining the completion of drying of the ceramic shell 4 using this invention is solely related to the temperature change curve during the drying process and is independent of the structure of the ceramic shell 4. This allows for precise drying of each batch of ceramic shells 4, effectively overcoming the problems of existing drying time control methods.

[0152] Meanwhile, the applicant's research indicates that during the drying process, the ceramic shell slurry cools down as moisture evaporates, and this evaporation also causes the ceramic shell to shrink (even with sand support). In the initial drying stage, the wax model also shrinks due to the cooling effect of the ceramic shell, causing it to adhere to the shrunken wax model surface. As the ceramic shell warms up, the wax model expands with the temperature increase; however, the shrinkage and expansion of the wax model due to temperature changes are slower than the changes in the ceramic shell. Therefore: If the cooling time for the ceramic shell is too long (i.e., the cooling range is small and the drying time is too long), the wax model will completely shrink under prolonged low temperatures. This will cause the ceramic shell to adhere to the significantly shrunken wax model, resulting in significant spatial deformation in the final casting and affecting casting accuracy. Furthermore, when the wax model expands upon reheating, the excessive shrinkage-expansion ratio can easily break the solidified ceramic shell that adheres to the shrunken wax model surface, leading to ceramic shell failure or irregular protrusions on the casting surface, further affecting casting accuracy. Moreover, excessively long drying times also reduce the efficiency of ceramic shell preparation.

[0153] If the cooling time of the ceramic shell is too short, that is, the cooling range is too large and the drying time is too short, the deep holes will not be completely dried while the surface is already over-dried. In other words, the window period for adjusting the drying time is very short, which is not conducive to adjusting the drying time of each part of the ceramic shell 4 to be dried, and increases the difficulty of controlling the drying uniformity of the ceramic shell 4 to be dried.

[0154] Because thin-film ceramic shells have a lower slurry concentration and higher moisture content, less slurry can be applied during coating, resulting in a thinner layer of ceramic shell and better thermal conductivity. This makes thin-film ceramic shells prone to various adverse problems caused by excessively long or short cooling times. Therefore, the control precision required for the drying process is too high, making it difficult to achieve.

[0155] Compared to thin-slurry ceramic shells, thick-slurry ceramic shells have a higher slurry concentration and lower moisture content, allowing for more slurry to adhere during application. This results in thicker layers and poorer thermal conductivity. Under the invention-defined condition where T2 is 5-7°C lower than T1, the ceramic shell achieves a more suitable drying rate. This ensures efficient drying while preventing excessively rapid drying in different parts of the shell, which would make adjusting the drying process difficult. Furthermore, drying can be completed before the wax mold has fully shrunk, allowing both the wax mold and the ceramic shell to return to room temperature, thus avoiding the problem of the wax mold cracking the ceramic shell.

[0156] This invention provides an exemplary method for determining the drying completion of a plurality of ceramic shells 4 to be dried, comprising: sequentially detecting the temperature of each deep hole of each ceramic shell 4 to be dried; and determining that the entire batch of ceramic shells 4 to be dried is dried when more than L% of the number of ceramic shells 4 to be dried are all dried. The L% = (L g-d ) / (L 0-d ) 100%, of which L g-d L represents the number of ceramic shells 4 to be dried after batch d has finished drying. 0-d This represents the total number of ceramic shells 4 to be dried in batch d. The value of L% is: 100% ≥ L% ≥ E%. Here, E is the preset threshold for the minimum percentage of dried ceramic shells 4 in batch d.

[0157] To improve the drying efficiency of ceramic shells, multiple ceramic shells 4 with the same structure are often dried simultaneously in a single batch. Due to variations in the placement or hanging methods of these multiple shells, the degree of air exposure varies, resulting in differences in drying time. Therefore, a certain margin is needed for control. Vacuum rapid drying is stopped once the majority of the shells are dried to avoid over-drying of most shells while waiting for those with less air exposure to finish drying. The percentage preset threshold is determined based on the air exposure differences among the shells, generally set at no less than 98%. This ensures that even if some shells are not completely dry after drying, their moisture content will not be too high, allowing them to continue drying in subsequent processes until completion.

[0158] This invention provides an exemplary wind turbine control analysis method A, comprising: For all fan units p with deep pores on the surface of the ceramic shell 4 to be dried, the following method is adopted: Step 3.1 Obtain the total number of deep holes D0 on the surface of the ceramic shell 4 to be dried facing the fan unit p. p p represents the fan unit number located on different sides of the vacuum drying chamber 1.

[0159] Step 3.2 Calculate k S-p %=D p / D0 100%, the k S-p % represents the control parameter of the wind turbine unit p.

[0160] Step 3.3 Repeat steps 3.1 to 3.2 until you obtain k for all wind turbine units. S-p %.

[0161] For all fan units p whose ceramic shell 4 surface does not have deep pores and is to be dried, the following method is adopted: Calculate k F-p %=[1-D0 / (D0+1)] 100%, the k F-p % represents the control parameter of the wind turbine unit p.

[0162] The wind turbine control module will obtain k from all wind turbines. S-p % and k F-p % is sent to the corresponding wind turbine unit p to control wind turbine unit p to operate at full load k S-p % or k F-p % to run.

[0163] For example: the total number of deep holes on the surface of the ceramic shell 4 to be dried is D0=4; the total number of deep holes on the surface of the ceramic shell 4 to be dried facing fan group p=1 is D1=1; the total number of deep holes on the surface of the ceramic shell 4 to be dried facing fan group p=2 is D2=1; the total number of deep holes on the surface of the ceramic shell 4 to be dried facing fan group p=3 is D3=2; the remaining ceramic shells 4 to be dried have no deep holes and are provided with corresponding fan groups p=4, p=5, and p=6.

[0164] At this point, the calculation yields: k S-1 %=D1 / D0 100% = (1 / 4) 100% = 25%.

[0165] k S-2 %=D2 / D0 100% = (1 / 4) 100% = 25%.

[0166] k S-3 %=D3 / D0 100% = (2 / 4) 100% = 50%.

[0167] k F-4 %=k F-5 %=k F-6 %=[1-D0 / (D0+1)] 100% = (1 - 4 / 5) 100% = 20%.

[0168] The fan unit control and analysis method of this invention can automatically and adaptively adjust the operation of each fan unit based on the obtained distribution of deep holes in the ceramic shell 4 to be dried. This increases the airflow to the parts of the ceramic shell 4 with more deep holes, resulting in faster drying and facilitating rapid drying inside the deep holes. Conversely, the airflow to the parts with fewer or no deep holes decreases, slowing down the drying process and synchronizing the drying time with the parts with deep holes. This achieves drying in a shorter time while ensuring that the drying degree of each part of the ceramic shell 4 is consistent.

[0169] Moreover, this method is only related to the number and location of the deep holes in the ceramic shell 4 to be dried. For various types of structures, such as standard or non-standard structures, the method can achieve better drying control with shorter drying time and more uniform drying time for each part of the ceramic shell.

[0170] This invention provides an exemplary wind turbine control analysis method B, comprising: For all fan units p with deep pores on the surface of the ceramic shell 4 to be dried, the following method is adopted: Step 4.1 Obtain the total number of deep holes D0 on the surface of the ceramic shell 4 to be dried facing the fan unit p. p p represents the fan unit number located on different sides of the vacuum drying chamber 1.

[0171] Step 4.2 Based on D0 and D p The quantity, k, is obtained from the self-control parameter database. S-p %. The k S-p % represents the control parameter of the wind turbine unit p.

[0172] Step 4.3 Repeat steps 4.1 to 4.2 until you obtain k for all wind turbine units. S-p %.

[0173] For all fan units p whose ceramic shell 4 surface does not have deep pores and is to be dried, the following method is adopted: Based on the total number of deep pores D0 in the ceramic shell 4 to be dried, k is obtained from the self-control parameter database. F-p %. The k F-p % represents the control parameter of the wind turbine unit p.

[0174] The wind turbine control module will obtain k from all wind turbines. S-p % and k F-p % is sent to the corresponding wind turbine unit p to control wind turbine unit p to operate at full load k S-p % or k F-p % to run.

[0175] This invention provides an exemplary method for entering k into a control parameter database. S-p % and k F-p The methods include: Step 5.1 Simulate the same fan unit position and orientation as the target vacuum drying chamber 1 in the simulation equipment.

[0176] Step 5.2 Preset drying training for different pore distributions of the ceramic shell 4 to be dried, and determine the control parameter k of each fan unit p relative to full load for the optimal drying time under each pore distribution. S-p % and k F-p The percentage refers to the distribution of deep holes, including their orientation and number. The optimal drying time is the shortest time required for the deep holes and surface layer of the ceramic shell 4 to dry to dry synchronously.

[0177] Step 5.3 Repeat step 5.2 until the deep hole distribution under normal conditions is trained, and construct D0-D. p -k S-p % - k F-pThe deep hole-control parameter relationship group is set and stored in the control parameter database.

[0178] Using the fan unit control analysis method of this invention, a large number of comprehensive sets of deep hole-control parameter relationships under optimal conditions can be prepared in the database of the vacuum drying system through pre-experimentation. Thus, when the total number of deep holes D0 of the ceramic shell 4 to be dried is obtained, the total number of deep holes D on the surface of the ceramic shell 4 facing the fan unit p to be dried can also be obtained. p Then, based on the deep hole-control parameter relationship set pre-stored in the control parameter database, it can theoretically be matched with D0-D p The best related k S-p % and k F-p % Control the corresponding fan units.

[0179] Since the optimal results of the experiment are reflected in: at a specific D0 - D p Under the deep hole relationship group, with k S-p % - k F-p Controlling the fan unit's operation using % of the control parameters can minimize the drying time while ensuring that the drying degree of each part of the ceramic shell 4 is consistent. Since the drying time is closely related to the volume, surface area, and surface structure of the ceramic shell 4, this method needs to be combined with a digital model of the ceramic shell 4 for evaluation. Standard ceramic shells 4 are commonly used components and can be simulated in advance. Non-standard ceramic shells 4, being irregularly shaped parts designed according to requirements, have diverse structural forms that may not be covered in advance experiments. Furthermore, the control parameter database lacks the corresponding D0-D values ​​for these irregularly shaped ceramic shells 4. p - k S-p % - k F-p When considering the deep hole-control parameter relationship group, the example wind turbine control analysis method B cannot obtain the required D0-D0 values. p - k S-p % - k F-p The deep hole-control parameter relationship group should be analyzed using the fan unit control analysis method A provided in the example to obtain the D0-D corresponding to the irregular ceramic shell 4 to be dried. p - k S-p % - k F-p % of the deep hole-control parameter relationship group.

[0180] Example wind turbine control analysis method B and example wind turbine control analysis method A can be used separately or in combination.

[0181] This invention provides an exemplary wind turbine unit, which includes at least two wind turbines arranged in a row. The wind turbine unit control module performs synchronous control or individual control on the wind turbines within each wind turbine unit.

[0182] This invention provides, by way of example, a wind turbine control analysis method C based on a wind turbine unit having at least two wind turbines. This method, in addition to the aforementioned wind turbine control analysis method A or wind turbine control analysis method B, further includes: Step 6.1 Construct a three-dimensional coordinate system based on the preset scanning starting point of the scanning device 207.

[0183] Step 6.2 During the displacement process of the scanning device 207, the three-dimensional coordinate points in space are recorded, and during the model structure analysis process, the position, orientation and depth of the deep hole of the obtained ceramic shell 4 to be dried are marked with three-dimensional coordinate points.

[0184] Step 6.3 Obtain the coordinate system range U covered by the blowing direction of each fan in the fan unit p. p-e , where e is the natural number of the fan in fan unit p.

[0185] Step 6.4 Statistical analysis of U p-e Number of deep holes D within the coverage area up-e And the number of deep holes D within the overall coverage area of ​​the wind turbine unit p. up .

[0186] Step 6.5 Calculate k up-e %=(D up-e / D up ) k S-p %.

[0187] The wind turbine control module will obtain the k values ​​of each wind turbine within wind turbine unit p. up-e % is sent to the corresponding wind turbine to control the corresponding wind turbine to operate at full load k up-e % to run. For D up-e The fan corresponding to =0 operates at the lowest power.

[0188] For example, a fan unit p contains two fans, numbered p-1 and p-2 respectively. Since the fans are at a fixed position relative to the preset scanning starting point of the scanning device 207, the coordinate positions of fans p-1 and p-2 in the three-dimensional coordinate system constructed in step 6.1 are also fixed. At this time, fan p-1 can form a cylindrical air duct p-1 with the fan shaft axis as the central axis and a diameter R=100cm in the three-dimensional coordinate system. The intersection of this cylindrical air duct p-1 and the corresponding surface of the ceramic shell 4 to be dried is the coordinate system range U covered by fan p-1. p-1 Statistics U p-1 The number of deep holes Dup-1 For example, D up-1 =1、D up-2 =2, and the number of deep holes D within the overall coverage area of ​​the wind turbine unit p. up For example, D up =3. Therefore, we can calculate: k up-1 %=(D up-1 / D up ) k S-p % = (1 / 3) k S-p %.

[0189] k up-2 %=(D up-2 / D up ) k S-p % = (2 / 3) k S-p %.

[0190] That is, within the fan unit p, fan 1 is (1 / 3) k S-p The fan is operating at % capacity, with fan 2 at (2 / 3) capacity. k S-p The system is running in a % state.

[0191] Using the fan unit control analysis method C of this invention, the individual control parameters of each fan in the fan unit p can be obtained through calculation, thereby enabling individual control of multiple fans in the fan unit p. This method makes the air blown by the fan unit p onto the ceramic shell 4 to be dried more targeted, resulting in a more consistent drying time for different parts of the ceramic shell 4, especially the deep-pore distribution area and the non-deep-pore distribution area.

[0192] This invention provides an exemplary wind turbine control analysis method D based on a wind turbine unit having at least two wind turbines. This method, in addition to the aforementioned wind turbine control analysis method A or wind turbine control analysis method B, further includes: Step 7.1 Construct a three-dimensional coordinate system based on the preset scanning starting point of the scanning device 207.

[0193] Step 7.2 During the displacement process of the scanning device 207, the three-dimensional coordinate points in space are recorded, and during the model structure analysis process, the position, orientation and depth of the deep hole of the obtained ceramic shell 4 to be dried are marked with three-dimensional coordinate points.

[0194] Step 7.3 Obtain the coordinate system range U covered by the blowing direction of each fan in the fan unit p. p-e , where e is the natural number of the fan in fan unit p.

[0195] Step 7.4 Statistical analysis of U p-e Number of deep holes D within the coverage area up-e And the number of deep holes D within the overall coverage area of ​​the wind turbine unit p. up .

[0196] Step 7.5 According to D up and D up-e Retrieve the corresponding fan's k value from the control parameter database. up-e %, the k up-e % represents the control parameter of fan number e within fan unit p.

[0197] The wind turbine control module will obtain the k values ​​of each wind turbine within wind turbine unit p. up-e % is sent to the corresponding wind turbine to control the corresponding wind turbine to operate at full load k up-e % to run.

[0198] This invention provides an exemplary method for entering k into a control parameter database. up-e The methods include: Step 8.1 Simulate the same fan unit position and orientation as the target vacuum drying chamber 1 in the simulation equipment.

[0199] Step 8.2 Preset drying training for different pore distributions of the ceramic shell 4 to be dried, and determine the operating ratio k of each fan in each fan group p at relative full load corresponding to the optimal drying time under each pore distribution. up-e The percentage refers to the distribution of deep holes, including their orientation and number. The optimal drying time is the shortest time required for the deep holes and surface layer of the ceramic shell 4 to dry to dry synchronously.

[0200] Step 8.3 Repeat step 8.2 until the deep hole distribution under normal conditions is trained, and construct D. up - D up-e -k up-e The deep hole-control parameter relationship group is set and stored in the control parameter database.

[0201] Using the fan unit control analysis method of this invention, a large number of optimal conditions involving various scenarios can be prepared in the database of vacuum drying systems through pre-experimentation. up - D up-e - k up-e The deep hole-control parameter relationship group. Thus, when determining the coordinate system range U covered by the blowing direction of each fan within the fan unit p. p-e and U p-e Number of deep holes D within the coverage area up-e And the number of deep holes D within the overall coverage area of ​​the wind turbine unit p.up At that time, the D parameter can be pre-stored in the control parameter database. up - D up-e - k up-e The deep hole-control parameter relationship set is theoretically related to D. up - D up-e The best related k up-e Each fan is individually controlled according to the corresponding fan control parameters.

[0202] Similar to the example wind turbine control analysis method B, the example wind turbine control analysis method D is mainly applicable to the ceramic shell 4 to be dried, whose model structure is covered by the pre-simulation experiment. For the ceramic shell 4 to be dried, whose model structure is not covered by the pre-simulation experiment, the example wind turbine control analysis method C is used to obtain D. up - D up-e - k up-e % of the deep hole-control parameter relationship group.

[0203] The present invention provides an exemplary rapid vacuum drying system, comprising: a first data transmission module, a local database module, and a remote system module.

[0204] The first data transmission module is connected to the remote system module via a signal line or a wireless network.

[0205] The local database module serves as a control parameter database to store relevant deep hole-control parameter relationship sets and operation result data.

[0206] The remote system module collects the deep-hole-control parameter relationship groups and operating result data of each rapid vacuum drying system through the first data transmission module, and selects the deep-hole-control parameter relationship group corresponding to the best operating result from the same deep-hole relationship. Based on authorization and / or command and / or automatic synchronization, the deep-hole-control parameter relationship group corresponding to the best operating result is centralized through the remote system module and then synchronized to the local database module of each rapid vacuum drying system through the first data transmission module, or directly synchronized to the local database module of each rapid vacuum drying system through the first data transmission module.

[0207] When the rapid vacuum drying system retrieves the deep hole-control parameter relationship group from the local database module, if a new optimal deep hole-control parameter relationship group exists, it will retrieve that new optimal deep hole-control parameter relationship group first.

[0208] For example: Each rapid vacuum drying system is connected to a remote system module via the Internet. At this time, the local database module of each rapid vacuum drying system is targeting the D recorded in model A. up - D up-e- k up-e The optimal result corresponding to the deep hole-control parameter relationship group is B; at this time, a certain enterprise or equipment manufacturer discovers through experiments or accident that D... up - D up-e - k up-e The control parameter in the %deep hole-control parameter relationship group is adjusted to k. up-e %`, which yields a better result C than the optimal result B. At this point, the new D for model A records... up - D up-e - k up-e The deep hole-control parameter relationship group, and the corresponding optimal result C, are collected centrally through the remote system module of this invention, and then synchronized to the local database module of each rapid vacuum drying system through the first data transmission module, or directly synchronized to the local database module of each rapid vacuum drying system through the first data transmission module.

[0209] The data synchronization method described above in this invention can synchronize the optimal control parameters for a specific model obtained by a company or equipment manufacturer to all other networked rapid vacuum drying systems, thereby improving the performance of that model in D... up - D up-e The degree of optimization of control parameters under certain conditions improves drying efficiency. Therefore, this invention allows for continuous optimization and improvement of the control parameters of the fan unit and its individual fans during actual operation, thereby increasing overall drying efficiency and maximizing enterprise benefits.

[0210] The present invention provides an exemplary rapid vacuum drying system, which further includes a second data transmission module.

[0211] The remote system module is connected to the control system of the rapid vacuum drying system via a signal line connection or a wireless network connection through the second data transmission module, so as to send remote control commands to the control system and / or obtain control commands issued by the control system and / or obtain the operating status parameters of various electrical control devices in the rapid vacuum drying system.

[0212] The execution priority of remote control commands issued by the remote system module is higher than that of control commands issued by the control system.

[0213] This example of a rapid vacuum drying system can operate with the intervention of a remote system module, enabling remote control of the system. This approach exemplifies how suppliers can facilitate remote equipment adjustment and self-testing for users, improving the efficiency of both initial equipment adjustments and subsequent maintenance.

[0214] This invention provides an exemplary drying rack 3, comprising: a ceramic shell hanger 304 for suspending ceramic shells 4 to be dried. The ceramic shell hanger 304 has several hook grooves 305. The ceramic shells 4 to be dried are hooked onto the hook grooves 305 by hooks 11. A hanger support plate 302 is fixed to the bottom of the ceramic shell hanger 304. Several rollers 303 that can slide along a guide rail 301 are provided at the bottom of the hanger support plate 302. The guide rail 301 is fixed to the bottom surface inside the vacuum drying chamber 1.

[0215] Since the ceramic shell preparation process involves multiple sizing and corresponding drying operations, a convenient detachable fixing method is required between the ceramic shell 4 to be dried, the ceramic shell hanger 304, and the vacuum drying chamber 1. This invention provides a detachable fixing method between the ceramic shell 4 to be dried, the ceramic shell hanger 304, and the vacuum drying chamber 1. Specifically, the ceramic shell 4 to be dried can be hooked onto the hook groove 305 using a hook 11, allowing for convenient detachable fixing of the ceramic shell 4 to be hung / removed from the ceramic shell hanger 304. Furthermore, the ceramic shell hanger 304 slides into / out of the guide rail 301, achieving convenient detachable fixing between the ceramic shell 4 to be dried and the vacuum drying chamber 1.

[0216] The present invention provides an exemplary guide rail 301, on which a limiting block is provided on the side away from the opening and closing door of the vacuum drying chamber 1. For example... Figure 1 As shown, the guide rail 301 has a limiting block on the side near the adjustable component 108. This setting allows the ceramic shell hanger 304 to slide into a relatively fixed position in the vacuum drying chamber 1, so that the number of ceramic shells 4 to be dried facing the fan unit is approximately the same in each drying process, thus improving the stability of drying.

[0217] This invention provides an exemplary scanning device 207, which includes a thermal imager 2072. The method for making the drying time of each part of the ceramic shell to be dried tend to be consistent includes: Step 9.1 During the drying process of the ceramic shell 4 to be dried, the thermal imager 2072, along with the scanning device 207, performs real-time thermal imaging of the ceramic shell 4 to be dried and sends the images to the control system.

[0218] Step 9.2 Based on the heat distribution in the thermal imaging image, when the drying time exceeds the preset first drying time, the control system determines whether there is a region T where the high and low temperature difference exceeds the preset temperature difference threshold. If region T exists, the following determination and operation are performed: When the temperature in the low-temperature zone of region T is lower than the preset low-temperature threshold, the operating power of the corresponding fan unit in region T is reduced.

[0219] When the temperature in the high-temperature zone of region T exceeds the preset high-temperature threshold, the operating power of the corresponding fan unit in region T is increased.

[0220] When the time of existence of region T exceeds the preset time threshold, and the temperature of the low-temperature region of region T is higher than the preset low-temperature threshold and the temperature of the high-temperature region of region T is lower than the preset high-temperature threshold, the operating power of the wind turbine unit corresponding to region T is increased.

[0221] The present invention provides an example of a preset low temperature threshold, which is 12-15℃.

[0222] The present invention provides an example of a preset high temperature threshold, which is 26-28℃.

[0223] The present invention provides an exemplary first drying time of 1-3 minutes.

[0224] The present invention provides an example of a preset time threshold, which is 30-60 seconds.

[0225] One of the main problems this invention aims to solve is to ensure that the drying degree and drying time of each part of the ceramic shell 4 are consistent. The method described in this invention, which aims to make the drying time of each part of the ceramic shell 4 more consistent, allows for dynamic adjustment of the control parameters of each fan unit based on the temperature changes of each part in the overall thermal imaging of the ceramic shell 4 during the drying process, thus making the drying time of each part of the ceramic shell 4 more consistent.

[0226] This invention provides an exemplary rapid vacuum drying system, which further includes a vacuum tank 5. One end of the vacuum tank 5 is connected to a vacuum pump 8 via a second connecting pipe, and a third electrically controlled valve 9 is provided on the second connecting pipe. The other end of the vacuum tank 5 is connected to a vacuum drying chamber 1 via a third connecting pipe 7, and a fourth electrically controlled valve 6 is provided on the third connecting pipe 7.

[0227] At this point, the added vacuum tank 5 can achieve instantaneous pressure reduction, specifically including: First, before depressurization, close the fourth electronic control valve 6 and pre-evacuate the vacuum tank 5 to a low vacuum state.

[0228] Then, during the depressurization, the fourth electrically controlled valve 6 is opened, connecting the vacuum drying chamber 1 with the vacuum tank 5, and instantly reducing the pressure to a balanced low pressure within 0.5 seconds.

[0229] Finally, the vacuum pump 8 simultaneously extracts the gaseous components from the vacuum tank 5 and the vacuum drying chamber 1. After the vacuum level in the vacuum drying chamber 1 meets the preset target, the fourth solenoid valve 6 and the first solenoid valve 10 are closed. At the same time, the vacuum pump 8 continues to extract the gaseous components from the vacuum tank 5 until the vacuum tank 5 reaches a low vacuum state.

[0230] By combining existing continuous and stable pressure reduction technology with specific instantaneous pressure reduction operations, the drying time of the slurry shell film can be further shortened, the breaking strength coefficient can be further reduced, and the average thickness of the ceramic shell support layer can be further increased. This achieves the goal of maintaining sufficient support while ensuring that the slurry ceramic shell also has an excellent breaking strength coefficient, thus expanding the application range of slurry ceramic shells in precision casting.

[0231] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A rapid vacuum drying system for precision casting, characterized in that, include: Vacuum drying chamber (1), vacuum pump (8) and control system; the vacuum pump (8) performs vacuum treatment on the vacuum drying chamber (1); the vacuum drying chamber (1) is equipped with a drying rack (3), and the ceramic shell (4) to be dried is placed on the drying rack (3) for drying treatment; The vacuum drying chamber (1) is equipped with at least two sets of fans with different airflow directions around the drying rack (3); The control system includes a vacuum drying control module and a fan unit control module; the fan unit control module controls the start and stop of all fans and / or control parameters, so that the drying time of each part of the ceramic shell to be dried tends to be consistent. The vacuum drying chamber (1) is equipped with a three-dimensional detection mechanism (2); the three-dimensional detection mechanism (2) drives the scanning device (207) to move along the X-axis, Y-axis and Z-axis; The scanning device (207) includes at least: a camera device (2071); the camera device (2071) is used to acquire image data of the ceramic shell (4) to be dried; The control system includes: a ceramic shell analysis module; the ceramic shell analysis module acquires image data of the ceramic shell (4) to be dried and performs model structure analysis to obtain the position, orientation and depth of the deep hole of the ceramic shell (4) to be dried, and sends it to the fan unit control module; the fan unit control module performs fan unit control analysis based on the position, orientation and depth of the deep hole of the ceramic shell (4) to be dried, and controls the start and stop and / or control parameters of each fan unit according to the analysis results.

2. The rapid vacuum drying system for precision casting according to claim 1, characterized in that, The vacuum pump (8) is connected to the vacuum drying chamber (1) through a first connecting pipe, and a first electrically controlled switch valve (10) is provided on the first connecting pipe; the vacuum drying chamber (1) is connected to an air pipe (106), and a second electrically controlled valve (107) is provided on the air pipe (106); the vacuum drying control module controls the opening and closing of the vacuum pump (8), the first electrically controlled switch valve (10), and the second electrically controlled valve (107).

3. The rapid vacuum drying system for precision casting according to claim 1, characterized in that, The drying rack (3) is detachably installed inside the vacuum drying chamber (1); the ceramic shell (4) to be dried is detachably installed on the drying rack (3).

4. The rapid vacuum drying system for precision casting according to claim 1, characterized in that, The three-dimensional detection mechanism (2) includes: two parallel X-axis guide rails (201) arranged horizontally along the axial direction of the vacuum drying chamber (1) and located on both sides of the drying rack (3); and a Y-axis guide rail (202) arranged horizontally along the cross section of the vacuum drying chamber (1); each of the two X-axis guide rails (201) is provided with a first displacement device (203) that can move along the X-axis guide rail (201); the Y-axis guide rail (202) is fixed between the two first displacement devices (203) and is driven by the two first displacement devices (203) to move along the X-axis guide rail (201). 201) Displacement; The Y-axis guide rail (202) is provided with a second displacement device (204) that can be displaced along the Y-axis guide rail (202); The second displacement device (204) is provided with an electrically controlled telescopic device (205) that can extend and retract along the Z-axis in the vertical direction; The telescopic end of the electrically controlled telescopic device (205) is fixed with a scanning device (207) through an electrically controlled gimbal (206); The first displacement device (203), the second displacement device (204), the electrically controlled telescopic device (205), and the electrically controlled gimbal (206) are respectively connected to the control system signal.

5. The rapid vacuum drying system for precision casting according to claim 4, characterized in that, The control system includes a scanning device control module; the scanning device control module is used to control the movement of two first displacement devices (203), a second displacement device (204), an electrically controlled telescopic device (205), and an electrically controlled gimbal (206), so that the scanning device (207) can take pictures / scan the ceramic shell (4) to be dried from all directions to obtain the image / scanning data of the ceramic shell (4) to be dried.

6. The rapid vacuum drying system for precision casting according to claim 1, characterized in that, The model structure analysis includes image analysis: First, obtain the outer contour model data, deep hole location data, and deep hole depth data of the ceramic shell (4) to be dried; Then, the acquired image data is compared with the outer contour model data to determine the spatial orientation of the ceramic shell (4) to be dried in the vacuum drying chamber (1); Finally, the current position and orientation of the deep hole of the ceramic shell (4) to be dried are determined according to the spatial orientation of the ceramic shell (4), and the current position, orientation and depth data of the deep hole of the ceramic shell (4) to be dried are output.

7. The rapid vacuum drying system for precision casting according to claim 4, characterized in that, The scanning device (207) further includes a scanning distance measuring device (2073); the scanning distance measuring device (2073) is used to measure the distance between the ceramic shell (4) to be dried and the scanning device (207) in real time; The model structure analysis includes: Step 1.1 The scanning distance measuring device (2073) performs an all-round scan of the surface n of the ceramic shell (4) to be dried according to a preset line, and obtains the distance measurement data set G of all scanning points on the surface n relative to the scanning distance measuring device (2073). n ; Step 1.2 G of the ranging data set n Connect the end points to obtain the digital surface m of the surface n of the ceramic shell (4) to be dried; Step 1.3 Combine the image data to perform graphic analysis on the digital surface m of the ceramic shell (4) to be dried, and determine the basic surface, raised surface and groove surface of the digital surface m; Step 1.4 Calculate the difference C between each measuring point within the groove surface and each measuring point on the adjacent basic surface of the groove. mk-b , where mk is the groove numbered k on the digital surface m, and b is the additional number of the measuring point inside the groove mk; Step 1.5 Take C mk-b >K2 is a deep hole, take C mk-b >K3 is a through hole; where K2 is the preset deep hole judgment threshold, and K3 is the model width, model length or model height corresponding to the surface n of the ceramic shell (4) to be dried; Step 1.6 Statistically determine the location W of all deep holes on the digital surface m of the ceramic shell to be dried (4). mc The depth H corresponding to each deep hole mc , where c is the natural number of the deep hole in the digital surface m; Step 1.7 Repeat steps 1.1 to 1.6 until the location of the deep holes W on the entire surface of the ceramic shell (4) to be dried is scanned. mc Depth H mc Statistics completed. The orientation X of the deep hole is determined based on the surface n where the deep hole is located. mc ; Step 1.8 Output the location W of all deep holes on the surface of the ceramic shell (4) to be dried. mc Depth H mc Orientation X mc data.

8. The rapid vacuum drying system for precision casting according to claim 7, characterized in that, The method for obtaining the basic surface, raised surface, and grooved surface described in step 1.3 includes: Step 1.3.1 Obtain the image data corresponding to the digital surface m of the ceramic shell (4) to be dried, and obtain the image surface R by stitching the image data; Step 1.3.2 Perform feature recognition on the image plane R to obtain the feature region rn-m on the image plane R, where rn is the sequential number of the feature region in the digital surface m; Step 1.3.3 Adjust the digital surface m to have the same orientation and similar size as the image surface R; Step 1.3.4 Take the feature region rc-m with the largest continuous area as the basic surface, where rc-m belongs to rn-m; Step 1.3.5 Obtain the distance measurement point data for each non-fundamental surface feature region. The distance measurement points of the feature region that are greater than the distance measurement points of the adjacent fundamental surface are called groove points, and the distance measurement points of the feature region that are less than the distance measurement points of the adjacent fundamental surface are called convex points. Step 1.3.6 Using the feature area as the boundary, connect adjacent groove points and convex points to form groove surfaces and convex surfaces.

9. The rapid vacuum drying system for precision casting according to claim 7, characterized in that, The three-dimensional detection mechanism (2) is equipped with an electrically controlled telescopic device (205), and a scanning device (207) is fixed at the telescopic end of the electrically controlled telescopic device (205) via an electrically controlled gimbal (206).

10. The rapid vacuum drying system for precision casting according to claim 9, characterized in that, The model structure analysis also includes: Step 2.1 Based on the location of the deep hole, control the scanning ranging device (2073) to move to the location of the deep hole; Step 2.2 By adjusting the orientation of the scanning ranging device (2073) relative to the deep hole, multiple deep hole depth measurement data are obtained; Step 2.3 Correct the original deep hole depth data H using the deepest depth measurement data. m-c The corrected data H is obtained. m-c `.

11. The rapid vacuum drying system for precision casting according to claim 1, characterized in that, The scanning device (207) further includes an infrared temperature measuring device (2074); the control system includes a drying process analysis module, which acquires the measurement quantity of the infrared temperature measuring device (2074) to perform drying process analysis in order to determine whether the ceramic shell (4) to be dried has been dried. The drying process analysis includes: periodically or continuously measuring the internal temperature T of the deep hole; and measuring the deep hole temperature T. v - Curve Q of drying time t v When Q v When curve segments that conform to the preset curve pattern appear, it indicates that the drying of the ceramic shell (4) to be dried is completed; where v is the natural number of all the deep holes of the ceramic shell (4) to be dried.

12. The rapid vacuum drying system for precision casting according to claim 11, characterized in that, The preset curve pattern includes: the temperature T inside the deep hole gradually decreases from the initial drying temperature T1 to the temperature T2 with the drying time, and then gradually increases to the drying environment temperature T3 with the drying time. When the temperature T of the deep hole of the ceramic shell (4) to be dried goes through T1-T2-T3 and is maintained at the drying environment temperature T3 for a preset time U, it is judged that the drying is complete. The initial drying temperature T1 is 22-26℃, the temperature T2 is 5-7℃ lower than the initial drying temperature T1, and the drying environment temperature T3 is 24±1℃.

13. The rapid vacuum drying system for precision casting according to claim 12, characterized in that, When there are multiple ceramic shells (4) to be dried in the same batch, the temperature of each deep hole of each ceramic shell (4) to be dried is tested one by one. When more than L% of the ceramic shells (4) to be dried have been dried, it is determined that the entire batch of ceramic shells (4) to be dried has been dried; the L% = (L g-d ) / (L 0-d ) 100%, of which L g-d L represents the number of ceramic shells (4) to be dried after batch d has finished drying. 0-d The quantity of all ceramic shells (4) to be dried in batch d; where L% is 100%≥L%≥E; where E is the preset threshold for the minimum percentage of drying completion of all ceramic shells (4) to be dried in batch d.

14. The rapid vacuum drying system for precision casting according to claim 1, characterized in that, The wind turbine control analysis includes: For all fan units p with deep pores on the surface of the ceramic shell (4) to be dried, the following method is adopted: Step 3.1 Obtain the total number of deep holes D0 on the ceramic shell (4) to be dried, and obtain the total number of deep holes D on the surface of the ceramic shell (4) to be dried facing the fan unit p. p ; p is the number of the fan unit set on different sides of the vacuum drying chamber (1); Step 3.2 Calculate k S-p %=D p / D0 100%, the k S-p % represents the control parameter of the wind turbine unit p; Step 3.3 Repeat steps 3.1 to 3.2 until you obtain k for all wind turbine units. S-p % For all fan units p whose ceramic shells (4) do not have deep pores on their surfaces to be dried, the following method is adopted: Calculate k F-p %=[1-D0 / (D0+1)] 100%, the k F-p % represents the control parameter of the wind turbine unit p; The wind turbine control module will obtain k from all wind turbines. S-p % and k F-p % is sent to the corresponding wind turbine unit p to control wind turbine unit p to operate at full load k S-p % or k F-p % to run.

15. The rapid vacuum drying system for precision casting according to claim 1, characterized in that, The wind turbine control analysis includes: For all fan units p with deep pores on the surface of the ceramic shell (4) to be dried, the following method is adopted: Step 4.1 Obtain the total number of deep holes D0 on the ceramic shell (4) to be dried, and obtain the total number of deep holes D on the surface of the ceramic shell (4) to be dried facing the fan unit p. p ; p is the number of the fan unit set on different sides of the vacuum drying chamber (1); Step 4.2 Based on D0 and D p The quantity, k, is obtained from the self-control parameter database. S-p % % The k S-p % represents the control parameter of the wind turbine unit p; Step 4.3 Repeat steps 4.1 to 4.2 until you obtain k for all wind turbine units. S-p % For all fan units p whose ceramic shells (4) do not have deep pores on their surfaces to be dried, the following method is adopted: Based on the total number of deep holes D0 in the ceramic shell (4) to be dried, k is obtained from the self-control parameter database. F-p % % The k F-p % represents the control parameter of the wind turbine unit p; The wind turbine control module will obtain k from all wind turbines. S-p % and k F-p % is sent to the corresponding wind turbine unit p to control wind turbine unit p to operate at full load k S-p % or k F-p % to run.

16. The rapid vacuum drying system for precision casting according to claim 15, characterized in that, Enter k into the control parameter database S-p % and k F-p The methods include: Step 5.1 Simulate the same fan unit position and orientation as the target vacuum drying chamber (1) in the simulation equipment; Step 5.2 Preset drying training for different pore distributions of the ceramic shell (4) to be dried, and determine the control parameter k of each fan unit p relative to full load for the optimal drying time under each pore distribution. S-p % and k F-p %; The distribution of deep holes includes: the orientation and number of deep holes; The optimal drying time is the shortest time for the deep holes and surface layer of each surface of the ceramic shell (4) to be dried to be dried synchronously completed; Step 5.3 Repeat step 5.2 until the deep hole distribution under normal conditions is trained, and construct D0-D p - k S-p % -k F-p The deep hole-control parameter relationship group is set and stored in the control parameter database.

17. The rapid vacuum drying system for precision casting according to any one of claims 14 or 15, characterized in that, The fan unit has at least two fans installed in a row; the fan unit control module can control the fans in each fan unit synchronously or individually.

18. The rapid vacuum drying system for precision casting according to claim 17, characterized in that, The wind turbine control analysis also includes: Step 6.1 Construct a three-dimensional coordinate system based on the preset scanning starting point of the scanning device (207); Step 6.2 During the displacement process of the scanning device (207), the three-dimensional coordinate points in space are recorded, and during the model structure analysis process, the position, orientation and depth of the deep hole of the obtained ceramic shell (4) to be dried are marked with three-dimensional coordinate points; Step 6.3 Obtain the coordinate system range U covered by the blowing direction of each fan in the fan unit p. p-e , where e is the natural number of the fan in fan group p; Step 6.4 Statistical analysis of U p-e Number of deep holes D within the coverage area up-e And the number of deep holes D within the overall coverage area of ​​the wind turbine unit p. up ; Step 6.5 Calculate k up-e %=(D up-e / D up ) k S-p % The wind turbine control module will obtain the k values ​​of each wind turbine within wind turbine unit p. up-e % is sent to the corresponding wind turbine to control the corresponding wind turbine to operate at full load k up-e % to run; for D up-e The fan corresponding to =0 operates at the lowest power.

19. The rapid vacuum drying system for precision casting according to claim 17, characterized in that, The wind turbine control analysis includes: Step 7.1 Construct a three-dimensional coordinate system based on the preset scanning starting point of the scanning device (207); Step 7.2 During the displacement process of the scanning device (207), the three-dimensional coordinate points in space are recorded, and during the model structure analysis process, the position, orientation and depth of the deep hole of the obtained ceramic shell (4) to be dried are marked with three-dimensional coordinate points; Step 7.3 Obtain the coordinate system range U covered by the blowing direction of each fan in the fan unit p. p-e , where e is the natural number of the fan in fan group p; Step 7.4 Statistical analysis of U p-e Number of deep holes D within the coverage area up-e And the number of deep holes D within the overall coverage area of ​​the wind turbine unit p. up ; Step 7.5 According to D up and D up-e Retrieve the corresponding fan's k value from the control parameter database. up-e %, the k up-e % represents the control parameter of fan number e within fan unit p; The wind turbine control module will obtain the k values ​​of each wind turbine within wind turbine unit p. up-e % is sent to the corresponding wind turbine to control the corresponding wind turbine to operate at full load k up-e % to run.

20. The rapid vacuum drying system for precision casting according to claim 19, characterized in that, Enter k into the control parameter database up-e The methods include: Step 8.1 Simulate the same fan unit position and orientation as the target vacuum drying chamber (1) in the simulation equipment; Step 8.2 Preset drying training for different pore distributions of the ceramic shell (4) to be dried, and determine the operating ratio k of each fan in each fan group p under each pore distribution condition corresponding to the optimal drying time. up-e %; The distribution of deep holes includes: the orientation and number of deep holes; The optimal drying time is the shortest time for the deep holes and surface layer of each surface of the ceramic shell (4) to be dried to be dried synchronously completed; Step 8.3 Repeat step 8.2 until the deep hole distribution under normal conditions is trained, and construct D. up - D up-e -k up-e The deep hole-control parameter relationship group is set and stored in the control parameter database.

21. The rapid vacuum drying system for precision casting according to any one of claims 15 or 19, characterized in that, The rapid vacuum drying system includes: a first data transmission module, a local database module, and a remote system module; The first data transmission module is connected to the remote system module via a signal line or a wireless network. The local database module serves as a control parameter database to store relevant deep hole-control parameter relationship sets and operation result data; The remote system module collects the deep-hole-control parameter relationship groups and operation result data of each rapid vacuum drying system through the first data transmission module, and selects the deep-hole-control parameter relationship group corresponding to the best operation result from the same deep-hole relationship; and, based on authorization and / or instructions and / or automatic synchronization, centralizes the deep-hole-control parameter relationship group corresponding to the best operation result through the remote system module and then synchronizes it to the local database module of each rapid vacuum drying system through the first data transmission module, or directly synchronizes it to the local database module of each rapid vacuum drying system through the first data transmission module; When the rapid vacuum drying system retrieves the deep hole-control parameter relationship group from the local database module, if a new optimal deep hole-control parameter relationship group exists, it will retrieve that new optimal deep hole-control parameter relationship group first.

22. The rapid vacuum drying system for precision casting according to claim 21, characterized in that, The rapid vacuum drying system also includes a second data transmission module; The remote system module is connected to the control system of the rapid vacuum drying system via a signal line connection or a wireless network connection through the second data transmission module, so as to send remote control commands to the control system and / or obtain control commands issued by the control system and / or obtain the operating status parameters of various electrical control devices in the rapid vacuum drying system. The execution priority of remote control commands issued by the remote system module is higher than that of control commands issued by the control system.

23. The rapid vacuum drying system for precision casting according to claim 1, characterized in that, The drying rack (3) includes: a ceramic shell hanger (304) for hanging ceramic shells (4) to be dried; the ceramic shell hanger (304) is provided with several hook grooves (305); the ceramic shells (4) to be dried are hooked at the hook grooves (305) by hooks (11); a hanging bracket plate (302) is fixed at the bottom of the ceramic shell hanger (304); the bottom of the hanging bracket plate (302) is provided with several rollers (303) that can slide along the guide rail (301); the guide rail (301) is fixed on the bottom surface inside the vacuum drying chamber (1).

24. The rapid vacuum drying system for precision casting according to claim 1, characterized in that, The scanning device (207) includes: a thermal imager (2072); the method for making the drying time of each part of the ceramic shell to be dried tend to be consistent includes: Step 9.1 During the drying process of the ceramic shell (4) to be dried, the thermal imager (2072) along with the scanning device (207) takes real-time thermal images of the ceramic shell (4) to be dried and sends them to the control system; Step 9.2 Based on the heat distribution in the thermal imaging image, when the drying time exceeds the preset first drying time, the control system determines whether there is a region T where the high and low temperature difference exceeds the preset temperature difference threshold. If region T exists, the following judgment and operation are performed: When the temperature in the low-temperature zone of zone T is lower than the preset low-temperature threshold, reduce the operating power of the corresponding fan unit in zone T. When the temperature in the high-temperature zone of zone T exceeds the preset high-temperature threshold, the operating power of the corresponding fan unit in zone T is increased. When the time of existence of region T exceeds the preset time threshold, and the temperature of the low-temperature region of region T is higher than the preset low-temperature threshold and the temperature of the high-temperature region of region T is lower than the preset high-temperature threshold, the operating power of the wind turbine unit corresponding to region T is increased.

25. The rapid vacuum drying system for precision casting according to claim 24, characterized in that, The preset low temperature threshold is 12-15℃, the preset high temperature threshold is 26-28℃, the preset first drying time is 1-3 minutes, and the preset time threshold is 30-60 seconds.

26. The rapid vacuum drying system for precision casting according to claim 2, characterized in that, The rapid vacuum drying system further includes: a vacuum tank (5); one end of the vacuum tank (5) is connected to the vacuum pump (8) through a second connecting pipe, and a third electrically controlled valve (9) is provided on the second connecting pipe; the other end of the vacuum tank (5) is connected to the vacuum drying chamber (1) through a third connecting pipe (7), and a fourth electrically controlled valve (6) is provided on the third connecting pipe (7).

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