Gas pressure control system, 3D printing device, and material conveying system

Abstract

Provided in the present application are a gas pressure control system, a 3D printing device and a material conveying system. The gas pressure control system comprises: a cylinder, having a bottom and a sidewall provided around the bottom; a piston, having a rod portion and a head portion, the head portion of the piston being slidingly connected to the side wall of the cylinder, so as to move in the direction close to or away from the bottom of the cylinder, and a first chamber used for containing a gas being formed between the head portion of the piston and the bottom of the cylinder; a load module, which is installed on the rod portion of the piston, and the load module applying a pressure to the gas in the first chamber on the basis of the weight of the load module, so as to form a gas having a target pressure; and a pressure tapping opening, communicated with the first chamber so as to provide the gas having the target pressure for an external chamber. By means of the load module connected to the piston and the movement of the piston inside the cylinder, said system provides the gas having the target pressure, and said system has simple structure and implementation mode, involves low cost, and achieves a high precision for controlling the pressure value of gases.

Description

Gas pressure control system, 3D printing device and material conveying system Technical Field

[0001] The present application relates to the field of 3D printing, and specifically to a gas pressure control system, a 3D printing device, and a material conveying system. Background Art

[0002] A gas pressure control system is a system that controls the pressure of the gas that provides the driving force. Gas pressure control systems are used in a wide range of processing equipment to provide a stable gas pressure. For example, gas pressure control systems are very common in 3D printing devices that use material extrusion.

[0003] However, when using the gas pressure control system in the related art to provide stable gas pressure, the gas pressure control system needs to have high detection accuracy, precise control algorithm and fast action response speed, which is not only costly but also difficult to implement.

[0004] Summary of the Invention

[0005] The present application provides a gas pressure control system, a 3D printing device, and a material conveying system. The following describes various aspects of the embodiments of the present application.

[0006] In a first aspect, a gas pressure control system is provided, comprising: a cylinder having a bottom and a side wall arranged around the bottom; a piston having a rod and an end, the end of the piston being slidably connected to the side wall of the cylinder to move toward or away from the bottom of the cylinder, a first chamber for accommodating gas being provided between the end of the piston and the bottom of the cylinder; a load module mounted on the rod of the piston, the load module pressurizing the gas in the first chamber based on the weight of the load module to form gas with a target pressure; and a pressure taking interface connected to the first chamber to provide the gas with the target pressure to an external chamber.

[0007] According to a second aspect, a 3D printing device is provided, comprising a gas pressure control system and a material extrusion part; the gas pressure control system comprises: a cylinder having a bottom and a side wall arranged around the bottom; a piston having a rod and an end, the end of the piston being slidably connected to the side wall of the cylinder to move toward or away from the bottom of the cylinder, and a first chamber for accommodating gas is provided between the end of the piston and the bottom of the cylinder; a load module is installed on the rod of the piston, and the load module pressurizes the gas in the first chamber based on the weight of the load module to form a gas with a target pressure; a pressure taking interface is connected to the first chamber; the material extrusion part comprises: a material accommodating chamber, the material accommodating chamber is used to accommodate molten material, the material accommodating chamber is connected to the pressure taking interface to receive the gas with the target pressure output by the pressure taking interface; an extrusion port, the extrusion port is used to extrude the molten material.

[0008] According to a third aspect, a material conveying system is provided, comprising a gas pressure control system and a feeding device; the gas pressure control system comprises: a cylinder having a bottom and a side wall arranged around the bottom; a piston having a rod and an end, the end of the piston being slidably connected to the side wall of the cylinder to move toward or away from the bottom of the cylinder, and a first chamber for accommodating gas being provided between the end of the piston and the bottom of the cylinder; a load module being installed on the rod of the piston, the load module pressurizing the gas in the first chamber based on the weight of the load module to form a gas with a target pressure; a pressure taking interface being connected to the first chamber; the feeding device comprising: a feeding chamber, the feeding chamber comprising a feed port and a discharge port, the feed port being used to receive material; a power source, the power source being used to push the material to the discharge port to transport the material to the outside; wherein, the feed port or the discharge port is connected to the pressure taking interface to receive the gas with the target pressure output by the pressure taking interface.

[0009] The gas pressure control system in the embodiment of the present application provides gas with target pressure through a load module connected to the piston and the movement of the piston in the cylinder. The structure and implementation method are relatively simple, low-cost, and the control accuracy of the gas pressure value is high. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] FIG1 is a schematic structural diagram of a gas pressure control system provided in an embodiment of the present application.

[0011] FIG2 is a schematic structural diagram of a gas pressure control system provided in yet another embodiment of the present application.

[0012] FIG3 is a schematic structural diagram of a gas pressure control system provided in yet another embodiment of the present application.

[0013] FIG4 is a schematic structural diagram of a 3D printing device provided in an embodiment of the present application.

[0014] FIG5 is a schematic structural diagram of a 3D printing device provided in yet another embodiment of the present application.

[0015] FIG6 is a schematic structural diagram of a material conveying system provided in an embodiment of the present application.

[0016] FIG7 is a schematic structural diagram of a material conveying system provided in yet another embodiment of the present application.

[0017] FIG8 is a schematic structural diagram of a 3D printing device provided in yet another embodiment of the present application. DETAILED DESCRIPTION

[0018] The following will be combined with the accompanying drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the embodiments described are only part of the embodiments of the present application, not all of the embodiments. It should be understood that the same or similar reference numerals are used in the drawings to represent the same or similar components.

[0019] A gas pressure control system is a system that controls gas pressure to provide a stable pressure. Gas pressure control systems can be used in a wide range of processing equipment. For example, they can be used in material extrusion 3D printing devices or material conveying systems.

[0020] For example, material extrusion 3D printing devices are widely used in the 3D printing field because they can accommodate a wide variety of printing materials and can produce a wide range of printed parts. This type of 3D printing device requires molten material to be extruded through its extrusion port (or discharge port) onto a forming table, where the molten material is deposited and solidified layer by layer to form a 3D printed part.

[0021] To facilitate the conveying or extrusion of molten materials, pneumatic drive can be used in 3D printing devices to provide the driving force for the extrusion of molten materials. Precisely controlling the extrusion speed of the molten material requires a pneumatic pressure source with high control accuracy and stability. A gas pressure control system is used to ensure the control accuracy and stability of the pneumatic pressure source, thereby providing a stable pressure gas to the 3D printing device over a long period of time.

[0022] As another example, a material conveying system can be understood as a device that provides molten material to the outside world (for example, a 3D printing device). The material conveying system discharges the molten material from the discharge port of its feeding chamber through the power source therein to convey the molten material to the outside world. In order to control the discharge speed of the molten material to ensure the stability of the material conveying system, a gas pressure control system is usually used in the material conveying system to cooperate with the power source, or to become the power source to work. For example, the gas pressure control system can be used to communicate with the feed port or the discharge port to cooperate with the power source (screw or piston) to discharge the molten material stably. For another example, the gas pressure control system can be used to communicate with the feeding chamber to become a pneumatic power source to stably discharge the molten material in the feeding chamber. In the related art, the gas pressure control system usually includes a pressure sensor installed on the gas storage chamber, a gas inlet / outlet component installed on the gas storage chamber, and a controller. The operating principle of this gas pressure control system is as follows: a pressure sensor measures the pressure within the gas storage chamber, and a controller controls the operation of the gas introduction and discharge components based on the deviation between the measured pressure and the target pressure. Specifically, when the measured pressure is lower than the target pressure, the gas introduction component is controlled to introduce gas into the gas storage chamber until the pressure measured by the pressure sensor matches the target pressure. When the measured pressure is higher than the target pressure, the gas discharge component is controlled to discharge gas from the gas storage chamber until the pressure measured by the pressure sensor matches the target pressure.

[0023] The accuracy of this type of gas pressure control system depends on the detection accuracy of the pressure sensor, the control algorithm of the controller, and the response speed of the entire system. Therefore, the implementation of a high-precision gas pressure source is not only costly but also difficult.

[0024] In view of this, an embodiment of the present application provides a gas pressure control system, which provides gas with a target pressure through a load module connected to a piston and the movement of the piston in a cylinder. Its structure and implementation method are relatively simple, low-cost, and have high control accuracy for the gas pressure value.

[0025] The gas pressure control system 10 in the embodiment of the present application is described in detail below with reference to FIG. 1 .

[0026] As shown in FIG. 1 , the gas pressure control system 10 may include a cylinder 11 , a piston 12 , a load module 13 , and a pressure interface 14 .

[0027] The cylinder 11 has a bottom 111 and a side wall 112 disposed around the bottom 111. The cylinder 11 can be disposed in a vertical direction, in which case the side wall 112 forms a vertical sliding track so that the load module 13 below can work based on its weight.

[0028] The piston 12 has a rod 121 and an end 122. The end 122 is located at one end 123 of the rod 121 and is slidably connected to the side wall 112 of the cylinder. In other words, the side wall 112 of the cylinder forms a motion track for the end 122, and the end 122 can move along the side wall 112 of the cylinder toward or away from the bottom 111 of the cylinder 11. A first chamber 113 for accommodating gas is provided between the end 122 of the piston 12 and the bottom 111 of the cylinder 11. In other words, the end 122 of the piston 12, the bottom 111 of the cylinder 11, and the side wall 112 between the end 122 and the bottom 111 form the first chamber 113 for accommodating gas. The first chamber 113 is used to accommodate gas received from the outside to facilitate pressure stabilization control of the gas. In some embodiments, the first chamber 113 can also be referred to as a lower chamber.

[0029] The load module 13 can be understood as a weight of a specific weight. The load module 13 can be mounted on the other end 124 of the rod 121 of the piston 12 and can be detachably connected to the other end 124 of the rod 121. In other words, the load module 13 can be both fixedly connected to the other end 124 of the rod 121 and detachably connected thereto. The load module 13 can slide as the piston 12 slides up and down.

[0030] The load module 13 can apply pressure to the gas in the first chamber 113 based on its weight to form a gas having a target pressure (the target pressure can be marked as P). Specifically, the load module 13 can apply pressure to the gas in the first chamber 113 based on its own weight, the weight of the piston 12, and the area of ​​the first surface 124 of the end 122 of the piston 12 to form a gas having a target pressure. It should be noted that the first surface 124 is the surface of the end 122 facing the bottom 111 of the cylinder 11. In other words, the first surface 124 is the surface of the end 122 used to form the first chamber 113. In this embodiment of the present application, the weight of the load module 13 and / or the area of ​​the first surface 124 of the end 122 can change according to the change of the target pressure.

[0031] The target pressure P is calculated as: P = G / S. G is the sum of the weights of the load module 13 and the piston 12, and S is the area of ​​the first surface 124 of the end 122. It should be noted that G = Mg, where M is the sum of the masses of the load module 13 and the piston 12, and g is a constant. G can be 9.8 N / kg or 10 N / kg.

[0032] Taking g as 10N / kg as an example, if the area of ​​the first surface 124 is 0.001m 2 When the sum of the mass of the load module 13 and the mass of the piston 12 is 10 kg, P = 10 (kg) * 10 (N / kg) / 0.001 (m 2 ), by calculating the target pressure P is 10 5 Pa (i.e. 0.1 MPa). If the area of ​​the first surface 124 is 0.0008 m 2 When the sum of the mass of the load module 13 and the mass of the piston 12 is 24 kg, P = 10 (kg) * 10 (N / kg) / 0.001 (m 2 ), by calculating the target pressure P is 3*10 5 Pa (i.e. 0.3M Pa).

[0033] The embodiment of the present application does not impose any specific restrictions on the location of the load module 13, as long as the load module 13 can slide with the piston 12 and can pressurize the gas in the first chamber 113 through its weight. As an example, the load module 13 can be located in the interior 14 of the cylinder 11 and above the first chamber 113. As another example, as shown in Figure 1, the load module 13 can be located outside the cylinder 11 and above the first chamber 113. Placing the load module 13 outside the cylinder 11 makes it easier to remove or replace the load module 13.

[0034] The embodiment of the present application does not specifically limit the structural form of the load module 13. For example, the load module 13 can be formed by a load unit having a weight. For another example, the load module 13 can be formed by a plurality of load units having a weight, and the weights of the plurality of load units can be the same or different. For example, as shown in Figure 1, the load module 13 includes a load unit 131 and a load unit 132, wherein the weight of the load unit 132 can be less than the weight of the load unit 131. Setting the load module 13 to multiple load units can more conveniently adjust the weight of the load module 13 according to the value of the target pressure.

[0035] Continuing to refer to Figure 1, the pressure-taking interface 14 is communicated with the first chamber 113. On the one hand, the pressure-taking interface 14 can be used to introduce the gas of the external chamber (not shown in Figure 1) into the first chamber 113, so that the gas pressure control system 10 can perform pressure stabilization control on the gas in the external chamber to form a gas with a target pressure. On the other hand, the pressure-taking interface 14 can be used to provide the gas with the target pressure to the external chamber. That is to say, the pressure-taking interface 14 is formed as a passage between the external chamber and the first chamber 113 to communicate the gas in the external chamber with the gas in the first chamber 113. In view of this, the load module 13 pressurizes the gas in the first chamber 113 to form a gas with a target pressure, which is equivalent to pressurizing the gas in the external chamber to form a gas with a target pressure.

[0036] It should be noted that the external chamber in the embodiments of the present application may refer to another chamber other than the first chamber. For example, when the gas pressure control system is applied to a 3D printing device, the external chamber may be a material chamber for molten material, a control chamber for controlling the extrusion of molten material, or a molten material conveying pipeline, etc., where air pressure is required. For another example, when the gas pressure control system is applied to a material conveying system, the external chamber may be a feeding chamber.

[0037] The working principle of the gas pressure control system in the embodiment of the present application is as follows: the weight of the load module 13, the weight of the piston 12 and the first surface 124 can all be set to match the target pressure value. When the pressure value of the gas in the external chamber is lower than the target pressure, the force exerted by the gas in the first chamber 113 on the first surface 124 will be less than the force exerted by the weight of the load module 13 and the piston 12 on the first surface 124. At this time, the weight of the load module 13 and the piston 12 will apply a compressive force to the gas in the first chamber 113, so that the first chamber 113 will shrink (i.e., the piston 12 moves downward) until the force exerted by the gas in the first chamber 113 on the first surface 124 is equal to the force exerted by the weight of the load module 13 and the piston 12 on the first surface 124; when the pressure value of the gas in the external chamber is higher than the target pressure, the force exerted by the gas in the first chamber 113 on the first surface 124 will be greater than the force exerted by the weight of the load module 13 and the piston 12 on the first surface 124. At this time, The load module 13 and the piston 12 are subjected to a counterforce by the gas in the first chamber 113, causing the first chamber 113 to expand (i.e., the piston 12 moves upward) until the force exerted by the gas in the first chamber 113 on the first surface 124 equals the force exerted by the weight of the load module 13 and the piston 12 on the first surface 124. By adjusting the force exerted by the gas in the first chamber 113 on the first surface 124 to equal the force exerted by the weight of the load module 13 and the piston 12 on the first surface 124, the pressure of the gas in the first chamber 113 and the external chamber can be adjusted to the target pressure value.

[0038] In addition, when the target pressure value needs to be adjusted, it is only necessary to remove the current load module 13 and replace it with a load module 13 that matches the adjusted target pressure value.

[0039] By implementing the embodiments of the present application, gas with target pressure can be provided through the load module 13 connected to the piston 12 and the movement of the piston 12 in the cylinder 11. The structure and implementation method are relatively simple, low-cost and have high control accuracy for the gas pressure value.

[0040] The embodiment of the present application does not specifically limit the source of the gas in the external chamber.

[0041] As an implementation method, the gas in the external chamber can be directly provided by the gas source device, that is, the gas source device and the gas pressure control system 10 are directly connected to the external chamber, the gas source device provides gas pressure to the external chamber, and the gas pressure control system 10 controls the gas pressure provided by the gas source device to be the target pressure value.

[0042] As another implementation, the gas in the external chamber can be provided by a gas pressure control system. As shown in FIG1 , the gas pressure control system 10 includes a gas supply interface 15 . The gas supply interface 15 is in communication with the first chamber 113 and can be used to communicate with a gas source device (not shown in FIG1 ). After obtaining the air pressure source provided by the gas source device through the gas supply interface 15 , the air pressure source is stabilized and then provided to the external chamber through the pressure sampling interface 14 .

[0043] In some embodiments, the gas supply interface 15 can also obtain gas from the gas source device to ensure that the gas pressure control system 10 can work normally when the gas in the first chamber 113 is insufficient. Specifically, when there is a gas leak in the first chamber 113 or the external chamber or when the gas volume of the external chamber changes significantly (for example, when the gas pressure control system is used in a 3D printing device, since the size of the pneumatic material extrusion print head can change with the printing trajectory, the volume of the molten material extruded at certain moments will suddenly become much larger than the volume of the material extruded at the previous moment, thereby causing the gas volume of the external chamber to suddenly increase), the end 122 will slide toward the bottom 111 to the first limit position (or downward limit position). At this point, the force exerted by the gas in first chamber 113 on first surface 124 may be less than the force exerted by the weight of load module 13 and piston 12 on first surface 124. However, because piston 12 is in the first limit position, the weight of load module 13 can no longer provide compressive force on the gas in first chamber 113, thus causing pressure control system 10 to fail to provide normal pressure stabilization. To avoid this phenomenon, when piston 12 is in the first limit position, air can be replenished through air replenishment port 15 to allow the pressure of the gas in first chamber 113 to continue to rise to the target pressure value, thereby ensuring the normal operation of pressure control system 10.

[0044] The embodiments of the present application do not specifically limit the gas source device. For example, the gas source device can be an air pump or a high-pressure gas cylinder. In some embodiments, when the gas source device is a high-pressure gas cylinder, a pressure reducing valve can also be matched with the high-pressure gas cylinder.

[0045] As can be seen from the foregoing, the sealing of the first chamber 113 is crucial to the pressure stabilization performance of the gas pressure control system 10. To ensure the sealing of the first chamber 113, in some embodiments, as shown in FIG1 , the gas pressure control system 10 may further include a sealing element 16. The sealing element 16 is positioned between the end 122 of the piston 12 and the sidewall 112 of the cylinder 11 to prevent gas leakage from the first chamber 113.

[0046] As an implementation method, the end portion 122 of the piston 12 may have a mounting groove (not shown in FIG1 ) around its periphery, and the sealing element 16 may be disposed within the mounting groove. The present embodiment does not specifically limit the type and number of the sealing elements 16 , and these may be selected and adjusted as needed. For example, the sealing element 16 may be a V-ring, an O-ring, a sealing strip, or the like. The number of sealing elements 16 may be one or more.

[0047] In order to control the size of the gas pressure control system 10 or the sliding stroke of the piston 12, in some embodiments, as shown in Figure 1, the cylinder 11 also includes a top 116. The top 116 is located at the end of the cylinder 11 away from the bottom 111 and the top 116 can be located between the end 122 of the piston 12 and the load module 13. In view of this, the position of the top 116 can simultaneously define the above-mentioned first limit position and the second limit position. The first limit position is the limit position of the piston 12 sliding in the direction close to the bottom 111, and the second limit position is the limit position of the piston 12 sliding in the direction away from the bottom 111 (the second limit position can also be called the upward limit position).

[0048] Specifically, a side 117 of the top 116 close to the load module 13 can prevent the load module 13 and the piston 12 from sliding downward, and a side 118 of the top 116 close to the end 122 of the piston 13 can prevent the piston 12 and the load module 13 from sliding upward.

[0049] The top 116 can form a second chamber 119 with the end 122 of the piston 12. In some embodiments, the second chamber 119 can also be called an upper chamber. In order to prevent the air pressure of the second chamber 119 from affecting the pressure stabilization performance of the gas pressure control system 10, the second chamber 119 can be connected to the outside of the cylinder 11, that is, the air pressure in the second chamber 119 is the same as the air pressure in the space where the load module 13 is located. In some embodiments, the outside of the cylinder 11 is the atmospheric environment, so the air pressure in the second chamber 119 and the air pressure in the space where the load module 13 is located are both atmospheric pressure. By setting the second chamber 119 to be connected to the atmosphere, the current ambient pressure reference value can be clearly determined without the aid of a pressure measuring tool.

[0050] As previously mentioned, the gas pressure control system 10 can provide gas supply via the gas supply interface 15. To precisely control the gas supply, in some embodiments, as shown in FIG1 , the gas pressure control system 10 may further include a start-up gas supply switch 17 and a stop-up gas supply switch 18. The start-up gas supply switch 17 activates gas supply via the gas supply interface 15 when the piston 12 is in the first limit position. For example, when the piston 12 is in the first limit position, the start-up gas supply switch 17 may activate the gas source device connected to the gas supply interface 15 to provide gas supply. The stop-up gas supply switch 18 deactivates gas supply via the gas supply interface 15 when the piston 12 is in the second limit position. For example, when the piston 12 is in the second limit position, the start-up gas supply switch 17 may deactivate the gas source device connected to the gas supply interface 15 to provide gas supply. It should be understood that when the piston 12 is in the first limit position, the volume of gas in the first chamber 113 is the smallest, and when the piston 12 is in the second limit position, the volume of gas in the second chamber 113 is the largest.

[0051] In some embodiments, when the piston 12 is at the second extreme position, air can also be exhausted through the air supply interface 15 .

[0052] The embodiment of the present application does not impose any specific limitation on the position of the start-up gas supply switch 17 and the close-up gas supply switch 18 and the switch type, as long as the above functions can be achieved.

[0053] As an implementation, as previously described, in FIG1 , a side 117 of the top portion 116 near the load module 13 defines the first limit position of the piston 12, and a side 118 of the top portion 116 near the end 122 of the piston 13 defines the second limit position of the piston 12. Accordingly, the start-up air supply switch 17 can be located on the side 117 of the top portion 116 facing the load module 13, and the stop-up air supply switch 18 can be located on the side 118 of the top portion 116 facing the end 122 of the piston. Furthermore, the start-up air supply switch 17 and the stop-up air supply switch 18 can be configured as contact switches. When the piston 13 is in the first limit position, the load module 13 contacts the start-up air supply switch 17 to initiate air supply via the air supply interface 15. When the piston 13 is in the second limit position, the end 122 of the piston contacts the stop-up air supply switch 18 to terminate air supply via the air supply interface 15. This air supply structure is relatively simple to implement and its execution is relatively concise, achieving low-cost air supply control.

[0054] As another implementation, the start-up air supply switch 17 can also be located near the bottom 111 of the cylinder 11, and the stop-up air supply switch 18 can be located near the top 116 of the cylinder 11. When the end 122 of the piston 12 slides to the position of the start-up air supply switch 17, it can contact the start-up air supply switch 17 to start the air supply operation. When the end 122 of the piston 12 moves to the position of the stop-up air supply switch 18, it can contact the stop-up air supply switch 18 to stop the air supply operation. It should be understood that the start-up air supply switch 17 and the stop-up air supply switch 18 can also be displacement detectors or other detection devices.

[0055] In some scenarios, the sudden drop of piston 12 in the gas pressure control system or the aforementioned air replenishment action can cause fluctuations in the gas within the external chamber, which can affect the pressure stabilization performance of the gas pressure control system 10. For example, when the gas pressure control system 10 in the embodiments of the present application is applied to a 3D printing system, if the print head is a variable-size print head, because the size of the pneumatic material extrusion print head can change along the printing trajectory, the volume of the molten material extruded at certain moments can suddenly increase significantly compared to the volume of the material extruded at the previous moment, resulting in a sudden increase in the gas volume of the external chamber. This sudden change can cause the piston 12 of the gas pressure control system to suddenly drop, causing the gas within the first chamber to fluctuate. Furthermore, the piston 12 of the gas pressure control system may drop to its limit and be unable to continue to drop to compensate for the change in the gas volume of the external chamber. Alternatively, when using the aforementioned gas source device to replenish gas through the air replenishment port 15, the gas injected by the gas source device through the air replenishment port 15 may cause fluctuations in the gas pressure within the first chamber 113 or the external chamber. How to make the gas pressure control system 10 still provide stable pressure stabilization performance in these scenarios has become a further problem that needs to be solved.

[0056] One feasible implementation is to increase the volume of the cylinder, thereby increasing the volume of the first chamber 113, to form a larger chamber to accommodate and compensate for the sudden change in the gas volume of the external chamber. However, this approach increases costs and makes the design of the cylinder's cross-sectional area and piston stroke more difficult.

[0057] In view of this, in some embodiments, as shown in FIG2 , the gas pressure system 10 may further include a gas reservoir 19. The gas reservoir 19 is in communication with the first chamber 113 and the pressure port 14, respectively. The gas reservoir 19 is used to form an extension of the first chamber 113, creating a larger gas storage space than the gas volume of the first chamber 113. In other words, the first chamber 113 and the gas reservoir 19 can form a new first chamber, the volume of which is the sum of the volume of the original first chamber 113 and the volume of the gas reservoir 19. This new first chamber can accommodate and compensate for sudden changes in the volume of the external chamber without requiring major modifications to the cylinder 11. Thus, while maintaining the pressure stabilization performance of the gas pressure system 10, it also reduces costs and the design difficulty of the cylinder's cross-sectional area and piston stroke. Furthermore, the presence of the gas reservoir 19 can also smooth the drop of the piston 12 and / or the transient pressure caused by the gas source device supplying gas through the gas supply port 15, thereby providing long-term, high-precision pressure stabilization. It should be noted that in the embodiment of the present application, the volume of the gas reservoir 19 should be significantly larger than the volume of the first chamber 113, so as to effectively smooth out pressure fluctuations. For example, the volume of the gas reservoir 19 can be 5 times, 10 times, or 20 times the volume of the first chamber 113.

[0058] As mentioned above, the stroke of the piston 12 and / or the cross-sectional area of ​​the cylinder 11 can be adjusted. The embodiment of the present application does not impose any specific limitation on the stroke of the piston 12 and / or the cross-sectional area of ​​the cylinder 11, as long as the stroke of the piston 12 and / or the cross-sectional area of ​​the cylinder 11 can achieve dynamic tracking and pressure stabilization of the gas in the external chamber when the volume of the external chamber changes.

[0059] In some embodiments, as shown in FIG3 , cylinder 11 may not include a top or bottom. Therefore, to facilitate control of the stroke of piston 12, it can be customized to the distance between position x and position y as shown in FIG3 . The connection between air reservoir 19 and cylinder 11 forms the bottom of cylinder 11.

[0060] The present embodiment does not specifically limit the shape of piston 12. As one implementation, it may include a rod portion 121 and an end portion 122, as shown in Figures 1-2. As another implementation, as shown in Figure 3, piston 12 may include only rod portion 121, without the aforementioned end portion 122. The bottom portion 126 of rod portion 121 may be formed as the aforementioned force-bearing surface.

[0061] For the gas pressure system 10 shown in Figures 2 and 3, taking the external chamber as the material holding chamber for molten material in the 3D printing device as an example, when the gas volume of the material holding chamber increases, the piston 12 descends downward under the action of the load module 13 so that the gas in the material holding chamber has a target pressure. When the gas volume of the material holding chamber decreases, the piston 12 rises upward under the action of the load module 13 so that the gas in the material holding chamber has a target pressure. In addition, due to the provision of the gas storage portion 19, regardless of whether the piston 12 descends or rises under the action of the load module 13, the gas in the external chamber and the gas pressure system 10 can maintain a reasonable gas volume.

[0062] As mentioned above, the gas pressure system 10 may also include a gas supply interface 15 to obtain gas from the gas source device when the gas in the first chamber 113 is insufficient to ensure that the piston 12 in the gas pressure system 10 can enter a reasonable stroke range. The embodiment of the present application does not specifically limit the setting position of the gas supply interface 15. As one implementation method, as shown in Figure 1, the gas supply interface 15 is located in the first chamber 113. As another implementation method, as shown in Figures 2 and 3, the gas supply interface 15 is located in the gas storage part 19.

[0063] In order to more intuitively display the gas pressure and further ensure the pressure stabilization performance of the gas pressure system 10, in some embodiments, as shown in Figures 2 and 3, the gas storage portion 19 is further provided with a pressure detection unit 191. The embodiments of the present application do not specifically limit the type of pressure detection unit 191, as long as it can be used to detect the gas pressure value in the gas storage portion 19. As an implementation method, the pressure detection unit 191 can be a pressure sensor.

[0064] On the one hand, the pressure detection unit 191 can assist the load module 13 to make the gas in the first chamber 113 and the gas storage section 19 have a target pressure, and on the other hand, it can display the value of the target pressure so that the user can know the pressure stability. For example, the load module 13 may be damaged during use, so its actual weight may be different from the calibrated weight. Therefore, when the load module 13 is used to pressurize the gas in the first chamber 113 and the gas storage section 19 according to its weight, the pressure value of the gas formed may not reach the target pressure value. At this time, the pressure value of the gas in the current gas storage section 19 can be detected by the pressure detection unit 191, and the difference between the pressure value and the target pressure value can be used to determine whether gas replenishment or degassing is needed.

[0065] As mentioned above, any of the aforementioned gas pressure systems 10 can be applied to a 3D printing device, and the pressure interface 14 in the gas pressure system 10 can be connected to any chamber in the 3D printing device that requires gas pressure control.

[0066] For ease of understanding, the following schematically illustrates how the gas pressure system 10 is applied to a 3D printing device, in conjunction with Figures 4 and 5 . It should be understood that the 3D printing device referred to in the embodiments of this application refers to a device used for 3D printing. The 3D printing device may refer to the entire 3D printing system or to a portion of the components within the 3D printing system. For example, the 3D printing device may refer to a 3D print head.

[0067] As shown in Figure 4 , a 3D printing device 40 may include a material extrusion unit 41, a gas pressure system 10, and a sheet switch 42. The gas pressure system 10, as detailed in Figures 1-3 , may include the aforementioned cylinder 11, piston 12, load module 13, and pressure port 14. A detailed description is provided above and will not be repeated here.

[0068] The material extrusion portion 41 includes a material receiving cavity 411 and an extrusion port 412 .

[0069] The material chamber 411 may be provided with a material inlet 413. The material chamber 411 may receive and hold molten material through the material inlet 413. The material chamber 411 may be in communication with the pressure port 14 to receive gas at a target pressure outputted by the pressure port 14. The gas at the target pressure is used to provide an extrusion force for the molten material, facilitating its extrusion from the extrusion port 412.

[0070] The extrusion port 412 may be a continuously adjustable width extrusion port. For example, the width of the extrusion port 412 may vary with the contour of the material filling area.

[0071] The embodiment of the present application does not specifically limit the structure of the extrusion port 412 .

[0072] As an example, the extrusion port 412 may include a first end and a second end, and the first end and the second end may change positions as the slider slides to change the width of the extrusion port 412 defined by the first end and the second end.

[0073] As another example, the extrusion port 412 may include multiple channels 414, or be divided into multiple channels 414 (each channel may be a square hole or a round hole). The multiple channels 414 are connected to the material chamber 411 and are used to extrude the molten material into the current printing layer. The opening and closing of each channel of the multiple channels 414 can be controlled, so that the number of channels in the multiple channels 414 capable of extruding material can be dynamically changed to achieve the change of the width of the extrusion port 412.

[0074] Multiple switches 42 may be provided, and these switches 42 may be positioned outside the material chamber 411. The switches 42 may be used to control the opening and closing of the passage 414. As one implementation, the switches 42 may be sheet-shaped switches. Sheet-shaped switches may deform under temperature and / or voltage control. For example, the sheet-shaped switches may include one or more of the following: a piezoelectric bimorph, a bimetallic strip, a metal resistor that expands when heated, or a memory alloy.

[0075] The multiple switches 42 can be respectively connected to the multiple transmission members 421 to control the on and off of the multiple channels 414 through the transmission members 421. The transmission member 421 can be a blocking block, which can be set above the channel 414 and can move up and down according to the deformation of the switch 42. One end of the transmission member 421 is fixedly connected to the switch 42, and the other end can abut or move away from the channel 414. The embodiment of the present application does not specifically limit the shape and material of the transmission member 421. For example, the transmission member 421 can be a square or cylindrical blocking block, and its material can be metal, ceramic or other materials that can withstand high temperatures and have sufficient strength.

[0076] In some embodiments, as shown in FIG5 , the 3D printing device 40 may further include a feeding system 43. The feeding system 43 is connected to the material chamber 411 via a material inlet 413 and is used to heat the molten material and transfer the molten material to the material chamber 411. The feeding system 43 may be, for example, a pneumatic feeding system.

[0077] As shown in FIG5 , the pneumatic feeding system 43 is typically provided with a pneumatic delivery pipeline 431 and a material storage tank 432 connected to the pneumatic delivery pipeline 431. The material storage tank 432 is used to store heated molten material, and the pneumatic delivery pipeline 431 is used to deliver pressurized gas (e.g., high-pressure gas) into the material storage tank 432 to apply a compressive force to the molten material, thereby facilitating the extrusion of the highly viscous molten material from the extrusion port 412. The pressurized gas can be provided, for example, by a gas source device or a gas pressure control system 10.

[0078] Given this, pressure generated by the pressurized gas also exists within the material chamber 411. This pressure affects the control of the switch 42 via the transmission member 421. For example, when the switch 42 is located outside the material chamber 411, as the deformation of the control switch 42 drives the transmission member 421 downward to close the corresponding channel 414, this pressure creates an upward resistance to the transmission member 421. This requires a high pressure to close the switch 42, thus creating certain difficulties in controlling the opening and closing of the channel.

[0079] To address the above issues, as shown in FIG5 , the 3D printing device 40 in the embodiment of the present application further includes a control chamber 44. Multiple switches 42 are located within the control chamber 44, and a pneumatic delivery line 431 can be configured to be in pneumatic communication with the control chamber 44. This configuration allows the aforementioned pressurized gas to be delivered to the control chamber 44, thereby creating a pneumatic pressure within the control chamber 44. This pneumatic pressure is the same as the pneumatic pressure within the material chamber 411, meaning that the pneumatic pressure delivered to the material chamber 411 by the pneumatic feeding system 4 is balanced with the pneumatic pressure within the control chamber 44.

[0080] In this embodiment of the present application, switches 42 for controlling the on / off operation of multiple channels 414 are disposed within a control chamber 44. This control chamber 44 is then placed in pneumatic communication with a pneumatic delivery line 431 within a pneumatic feeding system 43, thereby allowing the switches 42 and the molten material to be exposed to the same air pressure. This allows the multiple switches 42 within the control chamber 44 to be controlled on / off by the air pressure provided by the pneumatic feeding system 43, thereby reducing the pressure required by the switch components themselves and simplifying control.

[0081] In the 3D printing device shown in FIG5 , since the material chamber 411 is connected to both the pneumatic feeding system 43 and the control chamber 44, in order to more freely set the position of the gas pressure control system 10, the material chamber 411 can be connected to the pressure interface 14 through the pneumatic feeding system 43 or the control chamber 44 to receive the gas at the target pressure output by the pressure interface 14. It should be understood that FIG5 only illustrates the example of the material chamber 411 being connected to the pressure interface 14 through the material storage tank 432. In actual applications, the material chamber 411 can be connected through any one of the material storage tank 432, the pneumatic delivery pipeline 431, or the control chamber 44.

[0082] As mentioned above, any of the aforementioned gas pressure systems 10 can also be applied to a material conveying system. For ease of understanding, the following exemplary description of how the gas pressure system 10 is applied to a material conveying system is provided with reference to FIG6-FIG7.

[0083] As shown in Figures 6 and 7 , the material conveying system 60 may include a feeding chamber 61, a gas pressure system 10, and a power source 62. As shown in Figures 1-3 , the gas pressure system 10 may include the aforementioned cylinder 11, piston 12, load module 13, and pressure port 14. A detailed description is provided above and will not be repeated here.

[0084] The feeding chamber 61 includes a feed port 611 and a discharge port 612. The feed port 611 is used to receive material. In some embodiments, the material may be, for example, solid material. Optionally, as shown in FIG6 , the feeding chamber 61 may be provided with a heating device 63 that can be used to heat the solid material into a molten state. In this case, the feed port 611 may also be referred to as a hopper. In other embodiments, the material may be a molten material.

[0085] The power source 62 can be used to push the material to the discharge port 612 to transport the material to the outside.

[0086] The embodiment of the present application does not impose any specific limitation on the power source 62 , as long as the power source 62 can cause the material to be discharged from the discharge port 612 .

[0087] As an implementation method, as shown in Figure 6, the power source 62 can be a screw, which converts the solid material into a molten material by rotating and moving in the feeding chamber, and pushes the molten material to the discharge port 612. Based on this, the pressure interface 14 of the gas pressure system 10 can be connected to the discharge port 612 to output gas with a target pressure to the space near the discharge port 612 in the feeding chamber 61, thereby ensuring that the screw continuously and stably discharges the material outward. Optionally, as shown in Figure 8, when the power source 62 is a screw, the material conveying system 60 can also include a drive motor 64 and a transmission system 65. The transmission system 65 can be, for example, a transmission gear or a transmission belt.

[0088] As another implementation, as shown in FIG7 , the power source 62 may also be air pressure capable of providing driving force, which can provide an extruding force on the material to push the material to the discharge port 612. Based on this, the pressure interface 14 of the gas pressure system 10 can be connected to the feed port 611 to output gas with a target pressure to the space near the feed port 611 in the feeding chamber 61. The gas with the target pressure forms the power source 62 to provide a stable driving force for material discharge.

[0089] It is understandable that the power source 62 may also be a piston or other device that can provide driving force to discharge the material, which will not be described in detail here.

[0090] The embodiment of the present application does not specifically limit the exterior, and the exterior may be related to the application scenario of the material conveying system.

[0091] As an example, when the material delivery system 60 is applied to the 3D printing device described above, as shown in FIG8 , the exterior portion may be a print head 50. The print head 50 may include a material chamber 51 and an extrusion port 52. The material chamber 51 is used to hold molten material for 3D printing. The extrusion port 52 is used to extrude the molten material onto the printing table. The extrusion port 52 may be any of the continuously adjustable width extrusion ports described above.

[0092] As shown in FIG8 , the material delivery system 60 may form part of a 3D printing device 80 . For example, the discharge port 612 in the material delivery system 60 may be connected to the material chamber 51 in the print head 50 , which contains the molten material. The material chamber 51 in the print head 50 is also connected to the gas pressure system 10 to provide stable pressurized gas to the material chamber. Specifically, the material chamber 51 is connected to the pressure port 14 , which provides high-precision, stabilized pressure gas to the material chamber 51 via the pressure port 14 , thereby ensuring that the print head 50 of the 3D printing device 80 can stably extrude material, thereby ensuring the print quality of the printed part.

[0093] Optionally, as shown in Figure 8, the gas pressure system 10 may further include a gas storage unit 19, which is consistent with the above description and will not be described in detail here. By using a gas pressure system 10 with a gas storage unit 19 in a 3D printing device 80, a long-term high-precision voltage stabilization performance can be provided for the print head 50. Those of ordinary skill in the art will appreciate that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this application.

[0094] In the several embodiments provided in this application, it should be understood that the disclosed system can be implemented in other ways. For example, the device embodiments described above are merely illustrative. For example, the division of the units is merely a logical function division. In actual implementation, there may be other division methods, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0095] The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed across multiple network units. Some or all of these units may be selected to achieve the purpose of this embodiment according to actual needs.

[0096] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit.

[0097] The above description is merely a specific embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in this application should be included in the scope of protection of this application. Therefore, the scope of protection of this application should be based on the scope of protection of the claims.

Claims

1. A gas pressure control system, characterized in that: include: A cylinder having a bottom and a side wall disposed around the bottom; A piston having a rod and an end, wherein the end of the piston is slidably connected to the side wall of the cylinder to move toward or away from the bottom of the cylinder, and a first chamber for containing gas is provided between the end of the piston and the bottom of the cylinder; a load module is installed on the rod of the piston, and the load module pressurizes the gas in the first chamber based on the weight of the load module to form gas with a target pressure; The pressure-taking interface is communicated with the first chamber to provide the gas with the target pressure to the external chamber.

2. The gas pressure control system according to claim 1, characterized in that: Also includes: The air storage part, the pressure taking interface is connected with the first chamber through the air storage part.

3. The gas pressure control system according to claim 1 or 2, characterized in that: Also includes: The air supply interface is connected to the first chamber.

4. The gas pressure control system according to any one of claims 1 to 3, characterized in that: The load module is located outside the cylinder, and the load module is detachably connected to the rod.

5. The gas pressure control system according to claim 3, characterized in that: Also includes: Starting the air supply switch, wherein the air supply switch starts the air supply action based on the air supply interface when the piston is at the first limit position; The air supply switch is closed, and the air supply switch closes the air supply action based on the air supply interface when the piston is at the second limit position.

6. The gas pressure control system according to claim 5, characterized in that: The cylinder also includes a top, which is located between the load module and the end, the start air supply switch is located on the side of the top facing the load module, and the close air supply switch is located on the side of the top facing the end of the piston, when the piston is in a first extreme position, the load module contacts the start air supply switch to start the air supply action based on the air supply interface, and when the piston is in a second extreme position, the end of the piston contacts the close air supply switch to close the air supply action based on the air supply interface.

7. The gas pressure control system according to any one of claims 1 to 6, characterized in that: Also includes: A sealing element is located between an end of the piston and a side wall of the cylinder.

8. The gas pressure control system according to any one of claims 1 to 7, wherein the cylinder further comprises a top portion, wherein the top portion and the end portion of the piston form a second chamber, and the second chamber is connected to the outside of the cylinder.

9. A 3D printing device, characterized in that: Including gas pressure control system and material extrusion part; The gas pressure control system comprises: A cylinder having a bottom and a side wall disposed around the bottom; A piston having a rod and an end, wherein the end of the piston is slidably connected to the side wall of the cylinder so as to move toward or away from the bottom of the cylinder, and a first chamber for containing gas is provided between the end of the piston and the bottom of the cylinder; a load module mounted on the rod portion of the piston, the load module pressurizing the gas in the first chamber based on the weight of the load module to form the gas with a target pressure; A pressure taking interface, connected to the first chamber; The material extrusion unit comprises: A material containing chamber, the material containing chamber being used to contain molten material, the material containing chamber being in communication with the pressure taking interface to receive the gas having the target pressure outputted by the pressure taking interface; An extrusion port is used to extrude the molten material.

10. The 3D printing device according to claim 9, characterized in that: The extrusion port is an extrusion port with continuously adjustable width.

11. The 3D printing device according to claim 9 or 10, characterized in that: The extrusion port includes a first end and a second end. The first end and the second end change positions as the slider slides, so as to change a width of the extrusion port defined by the first end and the second end.

12. The 3D printing device according to any one of claims 9 to 11, characterized in that: The extrusion port includes a plurality of channels connected to the material chamber, and the plurality of channels are used to extrude the molten material. The 3D printing device also includes: A control chamber, wherein a plurality of switches are disposed in the control chamber, and the plurality of switches are coupled with the plurality of channels to perform on-off control on the plurality of channels; A pneumatic feeding system is connected to the material chamber to convey the molten material to the material chamber, wherein the pneumatic feeding system comprises a pneumatic conveying pipeline and a material storage tank connected to the pneumatic conveying pipeline, and the pneumatic conveying pipeline is connected to the control chamber by gas; The material containing chamber is communicated with the pressure taking interface through the air pressure feeding system or the control chamber to receive the gas with the target pressure outputted by the pressure taking interface.

13. A material conveying system, characterized in that: include: Gas pressure control system and feeding device; The gas pressure control system comprises: A cylinder having a bottom and a side wall disposed around the bottom; The piston has a rod and an end, wherein the end of the piston is slidably connected to the side wall of the cylinder to move toward or toward the cylinder. The piston moves in a direction away from the bottom of the cylinder, and a first chamber for containing gas is provided between the end of the piston and the bottom of the cylinder; a load module mounted on the rod portion of the piston, the load module pressurizing the gas in the first chamber based on the weight of the load module to form the gas with a target pressure; A pressure taking interface, connected to the first chamber; The feeding device comprises: A feeding chamber, the feeding chamber comprising a feeding port and a discharging port, the feeding port being used to receive materials; A power source, the power source is used to push the material to the discharge port to transport the material to the outside; Wherein, the feed port or the discharge port is communicated with the pressure taking interface to receive the gas with the target pressure output by the pressure taking interface.

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