Array type electrohydraulic shock wave demolding method and device

Abstract

An array type liquid-electric shock wave demolding method and device, the method comprising: 1) fixing multiple shock wave generators at different positions on the surface of a mold to be demolded; 2) connecting the different shock wave generators to different channels of a high-voltage pulse generator through cables, and setting the discharge parameters of each channel; 3) filling the liquid medium into the liquid injection port of the shock wave generator, and sealing the liquid injection port; 4) the high-voltage pulse generator discharges based on the discharge parameters of each channel, and drives the electrode device of the corresponding shock wave generator to generate a shock wave, so that the casting sand on the cast workpiece falls off; 5) observing the demolding condition of the cast workpiece to determine whether it is completely demolded, if yes, entering step 6), if not, resetting the discharge parameters and returning to step 4); 6) cutting off the output of all channels, and discharging the remaining energy in the high-voltage pulse generator; 7) disassembling and cleaning the cast workpiece, and completing the demolding. The device comprises a high-voltage pulse generator, multiple shock wave generators, a mold to be demolded, casting sand, a cast workpiece, and several cables. The present application proposes an array type liquid-electric shock wave demolding method, which can set multiple shock wave generators at different positions according to the geometric structure of complex molds and castings. By applying voltage pulses with different time sequences and intensities to each generator, shock waves with different directions and intensities can be generated, and different demolding forces can be applied to different parts of the mold, so that the castings with complex structures can be effectively demolded. Compared with the traditional scheme, the present application has the characteristics of fast demolding speed, concentrated impact force, partition demolding, no damage to the mold and casting, flexible control, and high efficiency and environmental protection. It can be widely used in complex casting processes in the fields of aerospace, automobiles, etc.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of casting workpiece demolding, in particular to an array type liquid-electric shock wave demolding method and device. BACKGROUND

[0002] In the process of metal casting, a series of steps such as model making, injecting metal liquid into the model, metal liquid condensation forming, demolding, and casting treatment are generally required. The demolding process as one of the processes may affect the quality of the casting and the length of the casting cycle if not properly handled.

[0003] Traditional demolding techniques include the draw hook type demolding method and the separation type demolding method. However, the draw hook type demolding method is only suitable for relatively simple castings, and the separation type demolding method is only suitable for castings with depth and inclination. It is difficult to avoid damaging the castings when using these two methods to demold complex castings.

[0004] Compared with the traditional demolding technology, the liquid-electric shock wave demolding technology generates a powerful shock wave in the mold through liquid-electric effect, rapidly removing the solidified casting from the mold or making the casting sand fall off the casting. The liquid-electric shock wave demolding technology has faster demolding speed, cleaner demolding, higher efficiency, and does not cause damage to the mold and the surface of the casting.

[0005] The current liquid-electric shock wave demolding equipment mostly adopts a single generator structure, i.e., a shock wave generator is arranged at a position of the mold. This structure has good effect on simple molds and castings, but for complex structures or large-sized workpieces, the shock wave of the single generator often cannot completely remove the solidified casting, and other demolding measures are needed. SUMMARY

[0006] The purpose of the present application is to provide an array type liquid-electric shock wave demolding method and device.

[0007] The technical solution adopted to achieve the purpose of the present application is as follows: an array type liquid-electric shock wave demolding method, comprising the following steps:

[0008] 1) fixing a plurality of shock wave generators at different positions on the surface of a mold to be demolded.

[0009] 2) connecting the different shock wave generators to different channels of a high-voltage pulse generator through cables, and setting the discharge parameters of each channel.

[0010] 3) filling the liquid medium into the liquid injection port of the shock wave generator, and sealing the liquid injection port.

[0011] 4) discharging the high-voltage pulse generator based on the discharge parameters of each channel, and driving the electrode device of the corresponding shock wave generator to generate a shock wave, so that the casting sand on the casting workpiece falls off.

[0012] 5) observe the demolding condition of the casted workpiece, determine whether it is completely demolded, if yes, go to step 6), if no, reset the discharge parameters, and return to step 4).

[0013] 6) cut off the output of all channels, and discharge the remaining energy in the high-voltage pulse generator.

[0014] 7) disassemble and clean the casted workpiece, and complete the demolding.

[0015] Further, the number of the shock wave generators is set according to actual conditions.

[0016] The position of the shock wave generator is placed according to the structure of the casted workpiece and the mold to be demolded.

[0017] Further, the material of the bottom contact surface of the shock wave generator includes silica gel.

[0018] Further, the material of the electrode device of the shock wave generator includes tungsten copper.

[0019] Further, each channel of the high-voltage pulse generator is independently controlled.

[0020] Further, each channel of the high-voltage pulse generator includes a driving module, a charging circuit, a discharge circuit, an optoelectronic isolation module, and an output end.

[0021] The driving module controls the output timing through the driving switch, so that the energy stored in the high-voltage pulse generator is quickly released to form a high-voltage pulse output.

[0022] The charging circuit is used to charge the storage capacitor of the high-voltage pulse generator.

[0023] The discharge circuit is used to discharge the energy in the high-voltage pulse generator.

[0024] The optoelectronic isolation module is used to isolate the input and output signals, and protect the equipment from high-voltage damage.

[0025] The output end is used to output the high-voltage pulse.

[0026] Further, the discharge parameters of each channel include the start and end time of the output of each channel, the pulse amplitude, the pulse width, the pulse frequency, and the number of pulses.

[0027] Further, the factors for determining whether it is completely demolded include the residual condition of the casting sand inside the mold to be demolded.

[0028] Further, step 6) further includes cooling the equipment.

[0029] A device based on the above array type liquid-electric shock wave demolding method, comprising a high-voltage pulse generator, a plurality of shock wave generators, a mold to be demolded, casting sand, a cast workpiece, and a plurality of cables.

[0030] The high-voltage pulse generator is used to generate high-voltage pulses.

[0031] The shock wave generator is connected with the high-voltage pulse generator through the cable.

[0032] The shock wave generator is fixed at different positions on the surface of the mold to be demolded.

[0033] The shock wave generator receives the high-voltage pulse of the high-voltage pulse generator and emits a shock wave to the mold to be demolded.

[0034] The mold to be demolded is internally provided with the casting sand and the cast workpiece.

[0035] After the mold to be demolded receives the shock wave of the shock wave generator, the mold to be demolded and the cast workpiece vibrate, the casting sand falls off, and the demolding is completed.

[0036] The technical effect of the present application is self-evident. The present application provides an array type liquid-electric shock wave demolding method and device. According to the geometric structure of complex molds and castings, a plurality of shock wave generators can be arranged at different positions. By applying voltage pulses of different time sequences and intensities to each generator, shock waves of different directions and intensities can be generated to exert different demolding forces on different parts of the mold, thereby effectively removing the castings with complex structures. Compared with the traditional scheme, the present application has the characteristics of fast demolding speed, concentrated impact force, partition demolding, no damage to the mold and the casting, flexible control and high efficiency and environmental protection. It can be widely applied to complex casting processes in the fields of aerospace, automobiles and the like.

[0037] The present application provides a novel array type liquid-electric shock wave demolding method, which can provide multi-directional, time-sequential, size and frequency controllable liquid-electric shock waves. The discharge parameters of the present application can be controlled by a high-voltage pulse source, the shock wave intensity of different regions can be flexibly adjusted, the precise demolding of complex structure cast workpieces can be realized, the mold and the workpiece are maximally protected, and the demolding quality and efficiency of the cast workpiece are significantly improved.

[0038] The present application provides a novel array type liquid-electric shock wave demolding method, which can provide multi-directional, time-sequential, size and frequency controllable liquid-electric shock waves. The discharge parameters of the present application can be controlled by a high-voltage pulse source, the shock wave intensity of different regions can be flexibly adjusted, the precise demolding of complex structure cast workpieces can be realized, the mold and the workpiece are maximally protected, and the demolding quality and efficiency of the cast workpiece are significantly improved. BRIEF DESCRIPTION OF DRAWINGS

[0039] Figure 1 is a liquid-electric shock wave array demolding technology workflow diagram;

[0040] Figure 2 is a schematic diagram of an array liquid-electric shock wave demolding device;

[0041] Figure 3 is a cross-sectional view of a shock wave generator;

[0042] Figure 4 is a high-voltage pulse generator module diagram;

[0043] Figure 5 is a cross-sectional view of a liquid-electric shock wave generator;

[0044] Figure 6 is a schematic diagram of a liquid-electric shock wave array demolding technology;

[0045] In the figure, high-voltage pulse generator 1, shock wave generator 2, mold to be demolded 3, cast workpiece 4, serial port screen 5, charge-discharge channel 6, air vent 7, pouring gate 8, cable interface 9, sealing ring 10, electrode device 11, discharge electrode 12, liquid injection port 13, focal point 14, parabolic insulating shell 15, positioning hole 16, contact surface 17, casting sand 18. DETAILED DESCRIPTION

[0046] The application will be further described below in conjunction with examples, but should not be understood as limiting the above-mentioned subject matter of the application to the following examples. Various substitutions and modifications can be made according to ordinary technical knowledge and conventional means in the art without departing from the above-mentioned technical idea of the application, and all should be included in the protection scope of the application.

[0047] Example 1:

[0048] Reference Figures 1 to 6 An array liquid-electric shock wave demolding method, comprising the following steps:

[0049] 1) Fix multiple shock wave generators at different positions on the surface of the mold to be demolded.

[0050] 2) Connect different shock wave generators to different channels of the high-voltage pulse generator through cables, and set the discharge parameters of each channel.

[0051] 3) Fill the liquid medium into the liquid injection port of the shock wave generator, and seal the liquid injection port.

[0052] 4) The high-voltage pulse generator discharges based on the discharge parameters of each channel, and drives the electrode device of the corresponding shock wave generator to generate a shock wave, so that the casting sand on the cast workpiece falls off.

[0053] 5) Observe the demolding condition of the cast workpiece, determine whether it is completely demolded, if yes, go to step 6), if no, reset the discharge parameters and return to step 4).

[0054] 6) Cut off the output of all channels and discharge the remaining energy in the high-voltage pulse generator.

[0055] 7) Disassemble and clean the cast workpiece, complete demolding.

[0056] Example 2:

[0057] An array type of liquid-electric shock wave demolding method, the main technical content is seen in any one of examples 1 to 3, further, the material of the electrode device of the shock wave generator includes tungsten copper.

[0058] The position of the shock wave generator is placed according to the structure of the cast workpiece and the mold to be demolded.

[0059] Example 3:

[0060] An array type of liquid-electric shock wave demolding method, the main technical content is seen in any one of examples 1 to 2, further, the material of the bottom contact surface of the shock wave generator includes silica gel.

[0061] Example 4:

[0062] An array type of liquid-electric shock wave demolding method, the main technical content is seen in any one of examples 1 to 3, further, the material of the electrode device of the shock wave generator includes tungsten copper.

[0063] Example 5:

[0064] An array type of liquid-electric shock wave demolding method, the main technical content is seen in any one of examples 1 to 4, further, each channel of the high-voltage pulse generator is independently controlled.

[0065] Example 6:

[0066] An array type of liquid-electric shock wave demolding method, the main technical content is seen in any one of examples 1 to 5, further, each channel of the high-voltage pulse generator includes a drive module, a charging circuit, a discharge circuit, an optoelectronic isolation module and an output end.

[0067] The drive module controls the output timing through the drive switch, so that the energy stored in the high-voltage pulse generator is quickly released to form a high-voltage pulse output.

[0068] The charging circuit is used to charge the storage capacitor of the high-voltage pulse generator.

[0069] The discharge circuit is used to discharge the energy in the high-voltage pulse generator and discharge.

[0070] The photoelectric isolation module is used for isolating input and output signals and protecting equipment from high voltage damage.

[0071] The output end is used for outputting high voltage pulses.

[0072] Embodiment 7:

[0073] An array type liquid-electric shock wave demolding method, the main technical content of which is seen in any one of embodiments 1 to 6, further, the discharge parameters of each channel include the output start and end time, pulse amplitude, pulse width, pulse frequency, and pulse number of each channel.

[0074] Embodiment 8:

[0075] An array type liquid-electric shock wave demolding method, the main technical content of which is seen in any one of embodiments 1 to 7, further, the factors for judging whether the demolding is complete include the residual state of the casting sand inside the mold to be demolded.

[0076] Embodiment 9:

[0077] An array type liquid-electric shock wave demolding method, the main technical content of which is seen in any one of embodiments 1 to 8, further, the step 6) further includes heat dissipation of the equipment.

[0078] Embodiment 10:

[0079] A device based on the array type liquid-electric shock wave demolding method of any one of embodiments 1 to 9, comprising a high voltage pulse generator 1, a plurality of shock wave generators 2, a mold to be demolded 3, casting sand 18, a cast workpiece 4, and a plurality of cables.

[0080] The high voltage pulse generator 1 is used for generating high voltage pulses.

[0081] The shock wave generator 2 is connected to the high voltage pulse generator 1 through the cable.

[0082] The shock wave generator 2 is fixed at different positions on the surface of the mold to be demolded 3.

[0083] The shock wave generator 2 receives the high voltage pulses of the high voltage pulse generator 1 and emits shock waves to the mold to be demolded 3.

[0084] The mold to be demolded 3 is internally provided with the casting sand 18 and the cast workpiece 4.

[0085] After receiving the shock waves of the shock wave generator 2, the mold to be demolded 3 vibrates with the cast workpiece 4, so that the casting sand 18 falls off, and the demolding is completed.

[0086] Embodiment 11:

[0087] Referring toFigures 1 to 6 An array type electrohydraulic shock wave demolding method, comprising the following steps:

[0088] 1) Fix three shock wave generators at different positions on the surface of the mold to be demolded. Fix the three shock wave generators on the mold shell through bolts.

[0089] 2) Connect the different shock wave generators to different channels of the high-voltage pulse generator through cables, and set the discharge parameters of each channel.

[0090] 3) Fill the liquid medium into the liquid injection port of the shock wave generator, and seal the liquid injection port.

[0091] 4) The high-voltage pulse generator discharges based on the discharge parameters of each channel, and drives the electrode device of the corresponding shock wave generator to generate a shock wave, so that the casting sand on the cast workpiece falls off.

[0092] First, close the output switch of all channels of the high-voltage pulse generator, start the serial communication program to establish a connection with the generator, send control instructions for system initialization. According to the pre-set time sequence table, input it to the serial screen or mobile phone APP, and send the discharge parameters to the FPGA.

[0093] Then turn on the power supply switch of the drive circuit, start the pre-charge program channel by channel, monitor the charging voltage of each channel, and enter standby state after confirming that the preset value is reached. According to the time sequence set by the time sequence table, the pulse output signal is transmitted to the drive module through the opto-isolator module, and the high-voltage pulse is output to each channel by the discharge loop, driving the electrode device to discharge to generate a strong shock wave, which is gathered by the inner wall of the shock wave generator and transmitted to the mold and the casting. The shock wave pressure can destroy the bonding force between the sand particles, causing the sand to fall off, causing the casting and the sand to vibrate, using the inherent frequency difference to remove the sand attached to the casting, achieving demolding.

[0094] The voltage range of the high-voltage pulse generator based on the discharge parameters of each channel is 1kV-15kV, and the frequency range is DC-1Hz.

[0095] 5) Observe the demolding condition of the cast workpiece, determine whether it is completely demolded, if yes, go to step 6), if not, reset the discharge parameters and return to step 4).

[0096] If the demolding is not complete, check whether the corresponding parameters of the time sequence table need to be adjusted, such as increasing the number of pulses in a certain area, increasing the pulse amplitude, etc., and optimize the parameters in real time to achieve precise demolding control. Output the pulses in turn, and immediately send a stop output command when it is observed that the casting has completely separated from the mold.

[0097] 6) cut off the output of all channels, and release the remaining energy in the high-voltage pulse generator.

[0098] 7) disassemble and clean the cast workpiece, complete demolding.

[0099] The control mode of the liquid-electric shock wave array demolding technology can choose to write a timing table in advance to automatically control the liquid-electric shock wave demolding, or can choose to manually control the demolding according to the actual demolding effect.

[0100] Example 12:

[0101] An array type liquid-electric shock wave demolding method, the main technical content is seen in example 11, further, the number of said shock wave generator is set according to the actual situation.

[0102] The position of said shock wave generator is placed according to the structure of the cast workpiece and the mold to be demolded.

[0103] The number of shock wave generators is generally not more than 10, and if the number is too large, it is easy to cause the high-voltage source to be large in size, which is not convenient to carry.

[0104] As shown in Figure 6 , the shock wave generator is placed on the outer surface of the demolding mold when working, and the shock wave generator can be fixed through the threaded hole reserved on the surface of the mold.

[0105] As shown in Figure 2 , there is casting sand between the cast workpiece and the mold to be demolded, which is the object to be demolded.

[0106] Example 13:

[0107] An array type liquid-electric shock wave demolding method, the main technical content is seen in any one of examples 11 to 12, further, the material of the bottom contact surface of said shock wave generator includes silica gel.

[0108] Example 14:

[0109] An array type liquid-electric shock wave demolding method, the main technical content is seen in any one of examples 11 to 13, further, the material of the electrode device of said shock wave generator includes tungsten copper.

[0110] Example 15:

[0111] An array type liquid-electric shock wave demolding method, the main technical content is seen in any one of examples 11 to 14, further, each channel of said high-voltage pulse generator is independently controlled.

[0112] Example 16:

[0113] An array type electrohydraulic shock wave demolding method, the main technical content is seen in any one of embodiments 11 to 15, further, the high-voltage pulse generator module comprises a serial port screen, a Bluetooth module, a voltage and current detection module, an energy release discharge circuit, a heat dissipation module and a plurality of independently controllable charge and discharge channels. The main body is controlled by a field programmable gate array (FPGA), which can be connected to a mobile phone APP through a serial port screen or a Bluetooth module to set and adjust the discharge parameters.

[0114] Each channel of the high-voltage pulse generator comprises a driving module, a charging circuit, a discharge circuit, an optoelectronic isolation module and an output end.

[0115] The driving module controls the output timing by driving the switch, so that the energy stored in the high-voltage pulse generator is quickly released to form a high-voltage pulse output.

[0116] The charging circuit is used to charge the storage capacitor of the high-voltage pulse generator.

[0117] The discharge circuit is used to release the energy in the high-voltage pulse generator for discharge.

[0118] The optoelectronic isolation module is used to isolate the input and output signals and protect the equipment from high-voltage damage.

[0119] The output end is used to output high-voltage pulses.

[0120] Embodiment 17:

[0121] An array type electrohydraulic shock wave demolding method, the main technical content is seen in any one of embodiments 11 to 16, further, the discharge parameters of each channel include the output start and end time, pulse amplitude, pulse width, pulse frequency and pulse number of each channel.

[0122] Embodiment 18:

[0123] An array type electrohydraulic shock wave demolding method, the main technical content is seen in any one of embodiments 11 to 17, further, the factors for judging whether the demolding is complete include the residual state of the casting sand inside the mold to be demolded.

[0124] For example, for sand casting, the sign of complete demolding is that the surface of the casting is smooth, without residual sand particles or only a small amount of sand marks that are easy to handle (the area / number of sand marks is less than a preset threshold).

[0125] Generally, the parameters are set according to experience, and slight adjustment is made after observing the actual demolding condition after discharge.

[0126] Embodiment 19:

[0127] An array type of electrohydraulic shock wave demolding method, the main technical content is seen in any one of embodiments 11 to 18, further, the step 6) also includes cooling the device.

[0128] Embodiment 20:

[0129] An array type of electrohydraulic shock wave demolding method based on any one of embodiments 11 to 19, comprising a high-voltage pulse generator 1, a plurality of shock wave generators 2, a mold to be demolded 3, casting sand 18, a cast workpiece 4, and a plurality of cables.

[0130] The high-voltage pulse generator 1 is used to generate high-voltage pulses.

[0131] The shock wave generator 2 is connected to the high-voltage pulse generator 1 through the cable.

[0132] The shock wave generator 2 is fixed at different positions on the surface of the mold to be demolded 3.

[0133] The shock wave generator 2 receives the high-voltage pulses from the high-voltage pulse generator 1 and emits shock waves to the mold to be demolded 3.

[0134] The mold to be demolded 3 is internally provided with the casting sand 18 and the cast workpiece 4.

[0135] After receiving the shock waves from the shock wave generator 2, the mold to be demolded 3 vibrates with the cast workpiece 4, causing the casting sand 18 to fall off, and the demolding is completed.

[0136] Embodiment 21:

[0137] Referring to Figures 1 to 6 An array type of electrohydraulic shock wave demolding method and device, mainly including the following contents:

[0138] As Figure 2 and Figure 3 shown, it includes a plurality of shock wave generators 2, cables, a high-voltage pulse generator 1, a mold to be demolded 3, casting sand 18, and a cast workpiece 4. The purpose is to separate the cast workpiece 4 from the mold and the sand by electrohydraulic shock waves of different directions, intensities, and quantities. The shock wave generator 2 involved in the present application includes discharge electrode structure, material, gap distance, shock wave device structure, material, etc., which are all prior art and will not be described here. The device of the present application has universal applicability. The liquid inside the shock wave generator is used as the discharge medium. After the discharge electrode 12 applies high voltage, the liquid medium is broken down and forms a plasma channel, and then the plasma channel expands outward sharply and squeezes the surrounding liquid to produce a powerful shock wave. The present application mainly describes the layout of multiple shock wave generators, the timing control of the high-voltage pulse generator, and the advantages over a single shock generator.

[0139] Figure 2 It is a schematic diagram of an array type electrohydraulic shock wave demolding device, including a plurality of shock wave generators 2, cables, a high-voltage pulse generator 1, a mold to be demolded 3, casting sand 18, a cast workpiece 4, air vents 7, and a pouring gate 8, etc. The mold is a complex structure of a metal mold, which contains a pouring system, a cooling air permeation system, etc. The mounting position of the shock wave generator can be set on the surface of the mold according to the geometric structure of the cast workpiece to be demolded. The contact surface of the generator is tightly attached to the surface of the mold. The specific layout of the generator can be placed according to the specific structure of the workpiece and the mold, and the number of generators can be set as needed.

[0140] Figure 3 It is a sectional view of the shock wave generator, including a cable interface 9, an electrode device 11, a parabolic insulating shell 15, a liquid injection port 13, a positioning hole 16, a contact surface 17, and a sealing ring 10, etc. The liquid medium can be injected and discharged through the liquid injection port 13 of the side insulating layer of the parabolic insulating shell 15. The bottom contact surface 17 can be a silica gel material with a certain thickness and elasticity. The electrode device 11 is placed inside the generator, which is composed of two vertically placed tungsten-copper rod electrodes. The upper end of the electrode is a cable interface, which is connected to each channel of the high-voltage pulse generator through a cable. The discharge center is located at the focal point 14 of the parabolic surface. The electrohydraulic shock wave can propagate along the direction parallel to the opening of the parabolic surface after being reflected by the parabolic surface. Each generator is provided with a positioning hole 16 fixed to the mold for precise positioning, and the contact surface 17 at the bottom of the generator can be fixed through the positioning thread hole and tightly attached to the surface of the mold.

[0141] Figure 4 It is a high-voltage pulse generator module, which contains a serial port screen 5, a Bluetooth module, a voltage and current detection module, an energy discharge circuit, a heat dissipation module, and a plurality of independently controllable charging and discharging channels 6. The main body is controlled by a field programmable gate array (FPGA), which can be connected to a mobile phone APP through the serial port screen 5 or the Bluetooth module to set and adjust the discharge parameters. The high-voltage pulse generator contains multiple independently controllable channels, each channel including an independent drive module, a charging circuit, a discharge circuit, an optical isolation module, and an output end. The charging circuit charges the storage capacitor; the drive circuit drives the switch to control the output timing, and quickly releases the stored energy to form a high-voltage pulse output. The pulse voltage, pulse width, pulse frequency, pulse number, etc. of each channel can be set individually. Each channel is independently numbered and connected to a shock wave generator. The high-voltage pulse source is connected to the shock wave generator through a high-voltage cable. Before demolding, the shock wave timing table is prepared in advance according to the structure of the castings and the mold, and the output parameters of each channel are set.

[0142] The control mode of the liquid-electric shock wave array demolding technology can be selected to automatically control the liquid-electric shock wave demolding by pre-writing a timing table, or can be selected to manually control the demolding according to the actual demolding effect.

[0143] The automatic demolding by writing a timing table is that, according to the shape and size of the mold and the workpiece, the shock wave timing table can be prepared in advance by experience, which contains the output start and end time, pulse number, pulse amplitude and other parameters of each channel, and is set through the serial screen 5 or the mobile phone APP. The demolding process is also divided into three stages of start, middle and late in the timing table, and the parameters of each channel are adjusted in each stage to gradually increase the shock wave intensity. In the start stage of demolding, a small shock wave pressure is applied to the weak area to play a slow-release role; in the middle stage, the shock wave intensity and pulse number are gradually increased, and the static friction between the mold, the casting sand 18 and the workpiece is gradually reduced; in the late stage, a large shock wave is applied to the key area to finally realize complete demolding. The manual demolding is to manually control the pulse parameters of each channel according to the actual demolding effect, and finally realize complete demolding.

[0144] By using the technology, the shock wave intensity of different areas can be flexibly adjusted to realize accurate demolding of complex structure castings, maximize the protection of the mold and the workpiece, and improve the demolding quality and efficiency.

[0145] Embodiment 22:

[0146] Referring to Figures 1 to 6 An array type liquid-electric shock wave demolding method and device mainly includes the following contents:

[0147] Figure 4 It is a high-voltage pulse generator module diagram. Figure 5 It is a liquid-electric shock wave generator cross-sectional view. Figure 6 It is a schematic diagram of the liquid-electric shock wave array demolding technology. The specific structure has been described in the summary. Figure 1 It is a work flow chart of the liquid-electric shock wave array demolding technology.

[0148] Specific working process:

[0149] a. First, fix three shock wave generators (which can be set according to needs) on the mold shell by bolts. Fill the liquid medium in the three generators, and seal the liquid injection port. Connect each shock wave generator with the corresponding three independent channels of the high-voltage pulse generator through the cable, and check whether the cable connection of each interface is normal. Close the output switch of all channels of the high-voltage pulse generator, start the serial communication program to establish connection with the generator, send control instructions for system initialization. According to the pre-set timing table, input it into the serial screen or mobile phone APP, and send the discharge parameters to the FPGA.

[0150] b. Then open the driving circuit power switch, start pre-charge program, monitor the charging voltage of each channel, and enter standby state after reaching the preset value. According to the time sequence set by the time sequence table, the pulse output signal is transmitted to the driving module through the photoelectric isolation module in time sequence, and the high-voltage pulse is output to each channel by the discharge circuit, the electrode device is driven to discharge to generate strong shock wave, and the shock wave is gathered by the inner wall of the shock wave generator and transmitted to the mold and the casting. The shock wave pressure can destroy the binding force between the sand particles, make the sand fall off, make the casting and the sand vibrate, and use the inherent frequency difference to remove the sand attached to the casting, so as to realize demolding.

[0151] c. During the discharging process, the change of the gap between the casting, the casting sand 18 and the mold is observed constantly, if the demolding is not complete, whether the corresponding parameters of the time sequence table need to be adjusted, such as increasing the pulse number of a certain area, increasing the pulse amplitude, etc., the parameters are optimized in real time to realize accurate demolding control. Output the pulse in sequence, when it is observed that the casting has completely separated from the mold, immediately send the stop output command, cut off the high-voltage connection of all channels, and run the heat dissipation and pressure reduction program to discharge the remaining energy of the energy storage capacitor.

[0152] d. Finally, according to the use instruction, disassemble the casting, clean the equipment, and prepare for the next round of demolding.

Claims

1. An arrayed electrohydraulic shock wave demolding method, characterized by, The method comprises the following steps: 1) fixing a plurality of shock wave generators at different positions on the surface of a mold to be demolded; the material of the bottom contact surface of the shock wave generator comprises silica gel; 2) connecting the different shock wave generators to different channels of a high-voltage pulse generator through cables, and setting the discharge parameters of each channel; each channel of the high-voltage pulse generator is independently controlled; the discharge parameters of each channel include the start and end time, pulse amplitude, pulse width, pulse frequency and pulse number of each channel; 3) filling the liquid medium into the liquid injection port of the shock wave generator, and sealing the liquid injection port; 4) the high-voltage pulse generator discharges based on the discharge parameters of each channel, and drives the electrode device of the corresponding shock wave generator to generate a shock wave, so that the casting sand on the cast workpiece falls off; 5) observing the demolding condition of the cast workpiece to determine whether it is completely demolded, if yes, entering step 6); if not, resetting the discharge parameters and returning to step 4); 6) cutting off the output of all channels and discharging the remaining energy in the high-voltage pulse generator; 7) disassembling and cleaning the cast workpiece to complete the demolding.

2. A method of arrayed electrohydraulic impact wave demolding according to claim 1, characterized in that, The number of shock wave generators is set according to the actual situation; The position of the shock wave generator is placed according to the structure of the cast workpiece and the mold to be demolded.

3. The arrayed electrohydraulic shock wave demolding method according to claim 1, characterized in that, The material of the electrode device of the shock wave generator comprises tungsten copper.

4. The arrayed electrohydraulic shock wave demolding method according to claim 1, characterized in that, Each channel of the high-voltage pulse generator comprises a driving module, a charging circuit, a discharge circuit, an optoelectronic isolation module and an output end; The driving module controls the output time sequence through the driving switch, so that the energy stored in the high-voltage pulse generator is quickly released to form a high-voltage pulse output; The charging circuit is used for charging the storage capacitor of the high-voltage pulse generator; The discharge circuit is used for discharging the energy in the high-voltage pulse generator to discharge; The optoelectronic isolation module is used for isolating the input and output signals to protect the equipment from high-voltage damage; The output end is used for outputting high-voltage pulse.

5. The arrayed electrohydraulic shock wave demolding method according to claim 1, characterized in that, For sand casting, the factors for determining whether it is completely demolded include the residual condition of the casting sand inside the mold to be demolded.

6. The arrayed electrohydraulic impact wave demolding method according to claim 1, characterized in that, In step 6), the equipment is also cooled.

7. A device for electrohydraulic shock wave demolding based on the array method according to any of claims 1 to 6, characterized in that, It comprises a high-voltage pulse generator (1), a plurality of shock wave generators (2), a mold to be demolded (3), casting sand (18), a cast workpiece (4) and a plurality of cables; The high-voltage pulse generator (1) is used for generating high-voltage pulses; The shock wave generator (2) is connected to the high-voltage pulse generator (1) through a cable; The shock wave generator (2) is fixed at different positions on the surface of the mold to be demolded (3); The shock wave generator (2) receives the high-voltage pulse of the high-voltage pulse generator (1) and emits a shock wave to the mold to be demolded (3); The mold to be demolded (3) is internally provided with casting sand (18) and a cast workpiece (4); After receiving the shock wave of the shock wave generator (2), the mold to be demolded (3) and the cast workpiece (4) vibrate, so that the casting sand (18) falls off and the demolding is completed.

Images