Pressure differential hot bending forming system and hot bending forming method

Abstract

The present invention discloses a pressure differential hot bending forming system and a hot bending forming method. By using the pressure differential hot bending forming principle, it only needs to set a forming mold below the workpiece to be processed, and the workpiece to be processed can be bent and deformed by forming an air pressure difference on both sides of the workpiece to be processed to achieve a profiling effect, and no mold is needed above the workpiece to be processed, thereby reducing the use cost of the mold, reducing the contact between the workpiece to be processed and other solid surfaces, reducing damage to the surface of the workpiece to be processed during the forming process, and avoiding the problem of mold damage caused by the traditional upper mold-workpiece-lower mold pressing form, extending the service life of the mold, and further reducing the use cost of the mold. Therefore, the above-mentioned pressure differential hot bending forming system and hot bending forming method can reduce production costs and improve product quality, and are not limited to hot bending forming of 2D glass to 3D glass, and have a wide range of application value.

Description

Technical Field

[0001] The invention relates to the field of glass processing, and in particular to a pressure difference type hot bending forming system and a hot bending forming method. Background Art

[0002] 3D glass has become increasingly popular as a display panel for mobile terminals. It is a future industry development trend to match it with glass, ceramic or microcrystalline glass back covers that are compatible with new technologies such as 5G communications and wireless charging. Different 3D glass material index requirements are different, but the production process is basically the same: starting from 2D flat glass, using double-sided basic profiling graphite molds to hot-bend and form a 3D hyperbolic or quadrilateral shape, and then performing double-sided polishing and chemical tempering, and then going through multiple post-processes suitable for curved glass to obtain the finished curved glass panel and back cover.

[0003] In the process of 3D glass forming, hot bending is a key step. The traditional hot bending process generally includes three stages: preheating, forming, and cooling. Specifically, the 2D flat glass is placed in two upper and lower graphite molds, gradually softened by heat in the preheating section, then pressurized in the forming section, and finally annealed in the cooling section.

[0004] The main problems of traditional hot bending process are as follows:

[0005] 1. Compared with 2D and 2.5D glass, the cost of 3D glass products increases the cost of graphite molds, hot bending machines and other supporting equipment, such as surface polishing machines, screen printers, pad printers and laminating machines. The cost of hot bending machines is the main one, because the hot bending machine has a complex structure, many workstations, and requires high control accuracy for temperature, pressure and position, which results in a high cost for the machine. Another major product cost of 3D glass products is the direct consumption caused by the loss of a large number of graphite molds. Due to the softness of graphite, it is not easy to maintain the surface polishing degree during the hot pressing process after it meets the requirements. The molds near the corners and other places that are subjected to the greatest force during the pressing process are more likely to wear and dent, resulting in the life of general graphite molds not exceeding a few thousand pressing actions. The molds have a high scrap rate and a low lifespan, resulting in high mold consumption costs. Therefore, the cost of traditional 3D glass products is relatively high.

[0006] 2. The forced unification of the three different physical processes of heating, bending and cooling in the hot bending process of glass within the structure and rhythm of the hot bending machine will also cause non-ideal operation of the glass process and the formation of various special defects, leading to increased processing pressure and costs in the later stages.

[0007] 3. Various defects on the mold surface will be transferred to the glass surface during the hot pressing process, forming indentations or burns, etc., which will increase the difficulty and cost of the subsequent concave and convex surface polishing process and even lead to defective products. Summary of the invention

[0008] Based on this, it is necessary to provide a pressure differential hot bending forming system and a hot bending forming method that can reduce product costs and improve product quality.

[0009] A pressure differential hot bending forming system comprises an air supply mechanism, a vacuum pumping mechanism and a forming mechanism; the forming mechanism comprises a working chamber, a lower mold assembly, an upper cover assembly, a heating assembly and a driving device; the air supply mechanism is connected to the working chamber to provide protective gas to the working chamber, the lower mold assembly, the upper cover assembly and the heating assembly are located in the working chamber, the lower mold assembly has a vacuum chamber and is provided with a mold mounting position for mounting the mold on the upper portion, the vacuum chamber is respectively connected to the lower portion of the mold mounting position and the vacuum pumping mechanism, the upper cover assembly is located above the lower mold assembly and can be sealed with the lower mold assembly to form a positive pressure chamber, the mold mounting position is exposed in the positive pressure chamber, the air supply mechanism is connected to the upper cover assembly to provide positive pressure gas to the positive pressure chamber through the upper cover assembly, and the heating assembly is used to heat the workpiece to be processed from above the workpiece to be processed in the mold; the driving device is connected to the upper cover assembly to drive the upper cover assembly to move toward or away from the lower mold assembly.

[0010] In one embodiment, the lower mold assembly includes a lower mold support and a lower mold air guide tube mold arranged on the lower mold support, the lower mold support is sealedly connected to the bottom surface of the working chamber, the mold mounting position is provided above the lower mold air guide tube mold, the lower part of the lower mold air guide tube mold cooperates with the lower mold support and the bottom surface of the working chamber to form the vacuum chamber, the vacuum chamber is connected to the lower part of the mold mounting position through the air guide holes on the lower mold air guide tube mold, and the lower mold air guide tube mold is used to seal and cooperate with the upper cover assembly.

[0011] In one of the embodiments, the lower mold assembly is provided with a heat preservation assembly for heating and keeping the workpiece to be processed from below the workpiece to be processed.

[0012] In one of the embodiments, the thermal insulation component includes a plurality of infrared heating tubes, and the plurality of infrared heating tubes of the thermal insulation component are distributed in the lower mold air guide tube mold.

[0013] In one embodiment, the upper cover assembly includes an upper cover air guide tube mold and an air guide tube, one end of the air guide tube is connected to the air supply mechanism, and the other end is connected to the positive pressure chamber through an air guide hole on the upper cover air guide tube mold;

[0014] The driving device is connected to the upper cover air guide tube mold, and the upper cover air guide tube mold and the lower mold assembly can be sealed and matched to enclose the positive pressure cavity.

[0015] In one of the embodiments, the upper cover assembly also includes an upper cover bracket, the upper part of the upper cover bracket is provided with a guide hole, the upper cover air guide tube mold is fixed below the upper cover bracket, a buffer gap is provided between the upper cover air guide tube mold and the upper cover bracket, the air guide tube is a corrugated tube arranged in the buffer gap and one end of the air guide tube is connected to the air supply mechanism through the guide hole; the driving device is connected to the upper cover bracket.

[0016] In one of the embodiments, the heating assembly includes a plurality of infrared heating tubes, and the plurality of infrared heating tubes of the heating assembly are distributed in the upper cover air guide tube mold.

[0017] In one of the embodiments, the driving device is connected to the upper cover assembly via a guide rod movably provided above the working chamber, one end of the guide rod passes through the working chamber and is connected to the output shaft of the driving device, and the other end is connected to the upper cover assembly within the working chamber; an air guide hole is provided in the guide rod, and the air supply mechanism is connected to the upper cover assembly via the air guide hole of the guide rod.

[0018] In one of the embodiments, the pressure differential hot bending forming system also includes a porous air guide component, which is arranged below the upper cover assembly and opposite to the mold mounting position, and the air supply mechanism is connected to the porous air guide component through the upper cover assembly to provide positive pressure gas to the positive pressure chamber through the porous air guide component.

[0019] In one embodiment, the porous air-conducting component includes a porous contact heating plate and a honeycomb-type laminate. The porous contact heating plate is a porous flat-plate structure, and the honeycomb-type laminate has a honeycomb-shaped columnar pore structure. There are multiple porous contact heating plates, and adjacent porous contact heating plates are separated by the honeycomb-type laminate. The outermost two layers of the porous air-conducting component are both the porous contact heating plates.

[0020] In one embodiment, the gas supply mechanism includes a gas supply pipeline and a gas regulating component arranged on the gas supply pipeline, one end of the gas supply pipeline is used to connect to the gas source equipment, and the other end is connected to the working chamber and the upper cover assembly, and the gas regulating component is used for gas supply regulation.

[0021] In one embodiment, the gas supply pipeline includes a main gas supply pipeline, an upper cover gas supply pipeline and a working chamber gas supply pipeline. The upper cover gas supply pipeline has multiple gas supply pipelines to provide positive pressure gas with different air pressures and flow rates. One end of the main gas supply pipeline is used to connect to the gas source equipment, and the other end is connected to multiple upper cover gas supply pipelines and the working chamber gas supply pipeline. Multiple upper cover gas supply pipelines are respectively connected to the upper cover assembly, and the working chamber gas supply pipeline is connected to the working chamber.

[0022] In one of the embodiments, along the gas flow direction in the gas pipeline, the gas regulating assembly on the main gas supply pipeline includes a main control valve and a gas source filter connected in series in sequence, the gas regulating assembly on each of the upper cover gas supply pipelines includes a pressure regulating valve, a flow control valve and a main control valve connected in series in sequence, a buffer tank is further connected between the pressure regulating valve and the flow control valve on each of the upper cover gas supply pipelines, and the gas regulating assembly on the working chamber gas supply pipeline includes a flow control valve and a main control valve connected in series in sequence.

[0023] In one of the embodiments, the air inlet end of the working chamber air supply pipeline is connected to the upper cover air supply pipeline for providing the minimum air pressure, and the connection point is located between the pressure regulating valve and the flow control valve.

[0024] In one of the embodiments, an air pressure monitoring element is provided on the main air supply pipeline, an air pressure monitoring element is also provided on each of the upper cover air supply pipelines between the pressure regulating valve and the flow control valve and between the main control valve and the upper cover assembly, and an air pressure monitoring element is also provided on the working chamber air supply pipeline or the working chamber.

[0025] In one embodiment, the vacuum mechanism has a vacuum pipeline and a vacuum regulating component arranged on the vacuum pipeline. One end of the vacuum pipeline is used to connect with the vacuum equipment, and the other end is connected with the vacuum chamber. The vacuum regulating component includes a main control valve and a vacuum filter connected in series.

[0026] In one embodiment, the pressure differential hot bending forming system also includes a first feedback pipeline, one end of which is connected to the working chamber, and the other end is connected to the vacuum pipeline, and the connection point is located between the main control valve and the vacuum filter on the vacuum pipeline, and a main control valve is also provided on the first feedback pipeline.

[0027] In one embodiment, the pressure differential hot bending forming system also includes a second feedback pipeline, one end of which is connected to the working chamber, and the other end is connected to the vacuum pipeline, and the connection point is located between the connection point between the first feedback pipeline and the vacuum pipeline and the main control valve on the vacuum pipeline, a main control valve is also provided on the second feedback pipeline, and a buffer tank and another main control valve are also provided between the connection point between the vacuum pipeline and the first feedback pipeline and the connection point between the vacuum pipeline and the second feedback pipeline.

[0028] In one embodiment, the vacuum pumping pipeline is divided into three sections according to the connection points of the vacuum pumping pipeline with the first feedback pipeline and the connection points of the vacuum pumping pipeline with the second feedback pipeline, and each section is independently provided with an air pressure monitoring element.

[0029] In one of the embodiments, a pressure-limiting pipeline is provided on the working chamber, and a positive pressure-limiting valve is provided on the pressure-limiting pipeline.

[0030] In one of the embodiments, the pressure differential hot bending forming system further includes a pushing component, which is disposed on the working chamber and is used to push the mold to the mold installation position or pull it out from the mold installation position.

[0031] A pressure differential hot bending forming method, using the pressure differential hot bending forming system described in any of the above embodiments, the pressure differential hot bending forming method comprising the following steps:

[0032] Open the gas supply mechanism to introduce protective gas into the working chamber, place the workpiece to be hot-bent into the mold, and place the mold on the mold installation position;

[0033] Controlling the driving device to make the upper cover assembly move downward and cooperate with the lower mold assembly to enclose the positive pressure chamber;

[0034] Turning on the heating component to heat the workpiece from above;

[0035] The air supply mechanism and / or the vacuum mechanism are turned on to form an air pressure difference between the upper and lower sides of the workpiece to be processed, and non-contact hot bending is performed through the air pressure difference.

[0036] In one embodiment, the protective gas introduced into the working chamber needs to make the pressure in the working chamber not exceed 500Pa.

[0037] In one embodiment, the mold is a porous graphite mold.

[0038] In one embodiment, during the hot bending process, the air supply mechanism and / or the vacuum mechanism are opened and closed multiple times to repeatedly perform pressure differential hot bending on the workpiece until the expected requirements are met.

[0039] In one of the embodiments, during the hot bending forming process, the step of controlling and adjusting the air supply mechanism and / or the vacuum mechanism is further included so as to form different air pressure differences on both sides of the workpiece at different time periods of the hot bending forming.

[0040] Because the original state of the surface of the workpiece to be processed is a sufficient condition for its strength to reach the ideal value, any surface damage during the hot bending process, including scratches, contact, marks, etc., will produce microcracks on the surface, thereby causing its fracture strength to decline. Therefore, reducing the contact between the workpiece to be processed and the external environment and tools, including molds, can truly and effectively reduce the surface defects of the workpiece to be processed. Compared with the traditional press molding method that uses solid-solid surface contact pressure to act on the upper and lower molds, the above-mentioned pressure differential hot bending forming system and hot bending forming method use the pressure differential hot bending forming principle. It only needs to set a lower mold for molding below the workpiece to be processed. By forming an air pressure difference on both sides of the workpiece to be processed, the workpiece to be processed can be bent and deformed to achieve a profiling effect, and no mold is required above the workpiece to be processed, thereby reducing the cost of using the mold. Since only the lower mold is needed, non-contact hot bending can reduce the contact between the workpiece and other solid surfaces, reduce damage to the surface of the workpiece during the forming process, reduce indentations, and improve the yield rate. It can also avoid the problem of mold damage caused by the traditional upper mold-workpiece-lower mold pressing form, extend the service life of the mold, and further reduce the cost of mold use.

[0041] The pressure differential hot bending forming system and the hot bending forming method heat the top of the workpiece to be processed, and perform hot bending forming through heat conduction of the workpiece to be processed itself during the air pressure profiling process, so that the local temperature of the workpiece to be processed after the profiling action is completed is reduced through heat conduction and is no longer affected by the pressure difference of the air pressure profiling, thereby reducing the problem of scalding of the lower surface of the workpiece to be processed due to lower heating in traditional forming methods, and the lower surface temperature can also prevent the mold from transferring surface defects to the surface of the workpiece to be processed, which can reduce the difficulty and cost of subsequent cold processing and improve product quality.

[0042] Therefore, the pressure differential hot bending forming system and the hot bending forming method can reduce production costs and improve product quality. They are not limited to hot bending forming of 2D glass to 3D glass and have wide application value. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1 It is a schematic structural diagram of a pressure differential hot bending forming system according to one embodiment;

[0044] Figure 2 A schematic structural diagram of a porous gas guide component in one embodiment;

[0045] Figure 3 for Figure 2 A partially exploded schematic diagram of a porous gas guide component;

[0046] Figure 4 For use Figure 1Schematic diagram of different working modes of the pressure differential hot bending forming method of the pressure differential hot bending forming system shown;

[0047] Figure 5 It is a schematic diagram of the process of convex surface air pressure pressing profiling;

[0048] Figure 6 It is a schematic diagram of the process of concave surface air pressure pressing profiling. DETAILED DESCRIPTION

[0049] In order to facilitate the understanding of the present invention, the present invention will be described more fully below with reference to the relevant drawings. The preferred embodiments of the present invention are given in the drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the understanding of the disclosure of the present invention more thorough and comprehensive.

[0050] It should be noted that when an element is referred to as being "fixed to" another element, it may be directly on the other element or there may be an intermediate element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be an intermediate element at the same time.

[0051] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those generally understood by those skilled in the art of the present invention. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more related listed items.

[0052] like Figure 1 As shown, a pressure differential hot bending forming system 10 of one embodiment includes a forming mechanism 100, an air supply mechanism 200 and a vacuum pumping mechanism 300. The pressure differential hot bending forming system 10 can be used for, but not limited to, hot bending forming of glass.

[0053] In this embodiment, the molding mechanism 100 includes a working chamber 110, a lower mold assembly 120, an upper cover assembly 130, a heating assembly and a driving device 150. The gas supply mechanism 200 is connected to the working chamber 110 to provide protective gas to the working chamber 110. The lower mold assembly 120, the upper cover assembly 130 and the heating assembly are located in the working chamber 110. The lower mold assembly 120 has a vacuum chamber (VC) 121 and is provided with a mold mounting position (not shown in the figure) for mounting the mold 20 on the upper part. The vacuum chamber 121 is connected to the lower part of the mold mounting position and to the vacuum pumping mechanism 300 respectively. The upper cover assembly 130 is located above the lower mold assembly 120 and can be sealed with the lower mold assembly 120 to enclose a positive pressure chamber (PC) 131 (the figure shows the state where the positive pressure chamber 131 is open). When the upper cover assembly 130 cooperates with the lower mold assembly 120 to form a closed positive pressure chamber 131, the mold mounting position is exposed in the positive pressure chamber 131. The gas supply mechanism 200 is connected to the upper cover assembly 130 to provide positive pressure gas to the positive pressure chamber 131 through the upper cover assembly 130. The heating assembly is used to heat the workpiece 30 to be processed from above the workpiece 30 in the mold 20. The driving device 150 is connected to the upper cover assembly 130 to drive the upper cover assembly 130 to move toward or away from the lower mold assembly 120. When the upper cover assembly 130 moves toward the lower mold assembly 120, a positive pressure chamber 131 can be formed; when the upper cover assembly 130 moves away from the lower mold assembly 120, the positive pressure chamber 131 opens and communicates with the working chamber 110.

[0054] Specifically, in one embodiment, the lower mold assembly 120 includes a lower mold support 122 and a lower mold air guide tube mold 123 disposed on the lower mold support 122. The lower mold support 122 is generally a hollow cylindrical structure with openings at both ends. The lower portion of the lower mold support 122 is sealedly connected to the bottom surface of the working chamber 110, and a sealing ring 124 may be provided between the two for sealing. The lower mold air guide tube mold 123 has a plurality of air guide holes in the axial direction to form an air guide channel with a porous structure. The mold mounting position is provided above the lower mold air guide tube mold 123. The lower portion of the lower mold air guide tube mold 123 cooperates with the lower mold support 122 and the bottom surface of the working chamber 110 to form a vacuum chamber 121. The vacuum chamber 121 is connected to the lower part of the mold installation position through the air guide holes on the lower mold air guide tube mold 123. When the vacuum chamber 121 is evacuated, negative pressure can be formed below the workpiece 30 through the air guide holes on the lower mold air guide tube mold 123 and the porous mold 20, so that the workpiece 30 is tightly adsorbed in the mold 20. The lower mold air guide tube mold 123 is used to seal and cooperate with the upper cover assembly 130 to form a positive pressure chamber 131.

[0055] Further, in one embodiment, a heat preservation component for heating and keeping the workpiece 30 warm from below the workpiece 30 is provided on the lower mold assembly 120. In a specific embodiment, the heat preservation component includes a plurality of infrared heating tubes 161. The plurality of infrared heating tubes 161 of the heat preservation component are distributed in the lower mold air guide tube mold 123. Preferably, the plurality of infrared heating tubes 161 are far-infrared heating tubes and are evenly distributed in the lower mold air guide tube mold 123.

[0056] In one embodiment, the upper cover assembly 130 includes an upper cover air guide tube mold 132 and an air guide tube 133. The upper cover air guide tube mold 132 has a plurality of air guide holes to form an air guide channel with a porous structure. One end of the air guide tube 133 is connected to the air supply mechanism 200, and the other end is connected to the positive pressure chamber 131 through the air guide holes on the upper cover air guide tube mold 132. The driving device 150 is connected to the upper cover air guide tube mold 132. The upper cover air guide tube mold 132 and the lower mold assembly 120 can be sealed and matched to form a positive pressure chamber 131. As shown in the embodiment shown in the figure, the positive pressure chamber 131 is formed by the upper cover air guide tube mold 132 and the lower mold air guide tube mold 123, wherein the lower end of the upper cover air guide tube mold 132 has a sealing protrusion, and the upper end of the lower mold air guide tube mold 123 has a sealing groove, and the upper cover air guide tube mold 132 and the lower mold air guide tube mold 123 can be sealed and matched through the sealing protrusion and the sealing groove.

[0057] Further, in one embodiment, the upper cover assembly 130 further includes an upper cover bracket 134. A guide hole is provided above the upper cover bracket 134. The upper cover air guide tube mold 132 is fixed below the upper cover bracket 134. A buffer gap 135 is provided between the upper cover air guide tube mold 132 and the upper cover bracket 134. The air guide tube 133 is preferably a corrugated tube provided in the buffer gap 135, which is used to softly conduct the positive pressure airflow, and one end of the air guide tube 133 is connected to the air supply mechanism 300 through the guide hole on the upper cover bracket 134. The driving device 150 is connected to the upper cover bracket 134.

[0058] In one embodiment, the heating assembly includes a plurality of infrared heating tubes 141. The plurality of infrared heating tubes 141 of the heating assembly are distributed in the upper cover air duct mold 132. Preferably, the plurality of infrared heating tubes 141 are far-infrared heating tubes and are evenly distributed in the upper cover air duct mold 132.

[0059] In one embodiment, the driving device 150 is connected to the upper cover assembly 130 through a guide rod 151 that is movably arranged above the working chamber. One end of the guide rod 151 passes through the working chamber 110 and is connected to the output shaft of the driving device 150, and the other end is connected to the upper cover assembly 130 inside the working chamber 110. Preferably, a vacuum sealing flange 152 is sleeved on the guide rod 151. The vacuum sealing flange 152 is sealed with the outer wall of the guide rod 151 and the working chamber 110 by sealing rings 153 and 154 respectively. An air guide hole (not shown in the figure) is provided in the guide rod 151. The air supply mechanism 200 is connected to the upper cover assembly 130 through the air guide hole in the guide rod 151. As shown in the embodiment shown in the figure, the air supply mechanism 200 is connected to the air guide hole of the upper cover air guide tube mold 132 through the air guide hole in the guide rod 151 and the air guide tube 133 in turn, so as to apply positive pressure to the top of the workpiece 30 to be processed through these components.

[0060] In a specific embodiment, the driving device 150 is a telescopic cylinder, which can control the upper cover assembly 130 to move toward or away from the lower mold assembly 120 by controlling the extension and retraction of its output shaft.

[0061] Further, in an optional embodiment, if Figure 2 and Figure 3 As shown, the pressure differential hot bending forming system 10 also includes a porous air guide component 400. The porous air guide component 400 is used to be arranged below the upper cover assembly 130 and opposite to the mold installation position. The air supply mechanism 200 is connected with the porous air guide component 400 through the upper cover assembly 130 to provide positive pressure gas to the positive pressure chamber 131 through the porous air guide component 400. By arranging the porous air guide component 400 between the upper cover assembly 130 and the workpiece 30 to be processed, the hot air flow passing through the upper cover assembly 130 can be evenly blown to the surface of the workpiece 30 to be processed, avoiding surface warping caused by the contact between the cold air caused by convection and the glass surface.

[0062] In a specific embodiment, the porous gas-conducting component 400 includes a porous contact heating plate 410 and a honeycomb laminate 420. The porous contact heating plate 410 is a porous flat plate structure, and the honeycomb laminate 420 has a honeycomb columnar hole structure, such as but not limited to hexagonal columnar holes. There are multiple porous contact heating plates 410, and adjacent porous contact heating plates 410 are separated by honeycomb laminates 420. The outermost two layers of the porous gas-conducting component 400 are both porous contact heating plates 410. During hot bending, the porous contact heating plate 410 below the porous gas-conducting component 400 can contact the surface of the workpiece 30 to be processed to ensure the stability of the temperature above the workpiece 30 to be processed. More specifically, the length of the porous gas-conducting component 400 can be made according to the atmospheric pressure with a compression ratio of 15:1 to ensure that the gas temperature at a height of at least 10 times the thickness of the workpiece 30 to be processed remains unchanged.

[0063] Furthermore, in an optional embodiment, the differential pressure hot bending forming system 10 further includes a pushing assembly (not shown). The pushing assembly is disposed on the working chamber 110 and is used to push the mold 20 to the mold installation position or pull it out from the mold installation position.

[0064] In one embodiment, the gas supply mechanism 200 includes a gas supply pipeline and a gas regulating assembly disposed on the gas supply pipeline. One end of the gas supply pipeline 210 is used to connect to the gas source device 40 , and the other end is connected to the working chamber 110 and the upper cover assembly 130 .

[0065] In a specific embodiment, the gas supply pipeline includes a main gas supply pipeline 211, an upper cover gas supply pipeline 212, and a working chamber gas supply pipeline 213. The upper cover gas supply pipeline 212 has multiple positive pressure gas with different air pressures and flow rates. One end of the main gas supply pipeline 211 is used to connect to the gas source device 40, and the other end is connected to multiple upper cover gas supply pipelines 212 and the working chamber gas supply pipeline 213. Multiple upper cover gas supply pipelines 212 are respectively connected to the upper cover assembly 130, and the working chamber gas supply pipeline 213 is connected to the working chamber 110.

[0066] More specifically, in one embodiment, according to the different air pressures provided, there are three upper cover air supply pipelines 212, which are used to provide positive pressure gas of high pressure, medium pressure and low pressure respectively. The three upper cover air supply pipelines 212 can be connected to the upper cover assembly 130 respectively, or can be connected to the upper cover assembly 130 as shown in FIG. Figure 1 As shown, a common pipeline is set up in the rear section and connected to the upper cover assembly 130 through a common pipeline.

[0067] The gas regulating assembly is used for gas supply regulation. In one embodiment, the gas regulating assembly on the main gas supply pipeline 211 includes a main control valve 2111 and a gas source filter 2112 connected in series according to the gas flow direction. The gas regulating assembly on each upper cover gas supply pipeline 212 includes a pressure regulating valve 2121, a flow control valve 2122 and a main control valve 2123 connected in series according to the gas flow direction. A buffer tank 2124 is further connected between the pressure regulating valve 2121 and the flow control valve 2122 on each upper cover gas supply pipeline 212. The gas regulating assembly on the working chamber gas supply pipeline 213 includes a flow control valve 2131 and a main control valve 2132 connected in series according to the gas flow direction. Each main control valve can be a main control valve mainly used to control the on or off of the pipeline, each flow control valve can be a variety of throttle valves, such as a needle valve, each pressure regulating valve is used to maintain the gas pressure in the corresponding pipeline stable, and the pressure regulating valve can cooperate with the buffer tank to achieve a good pressure regulation and stabilization effect.

[0068] Furthermore, in one embodiment, the air inlet end of the working chamber air supply pipeline 213 is connected to the upper cover air supply pipeline 212 for providing the lowest air pressure, and the connection point is located between the corresponding pressure regulating valve 2121 and the flow control valve 2122 .

[0069] Preferably, the working chamber gas supply pipeline 213 is used to provide low-pressure protective gas, such as low-pressure nitrogen, into the working chamber 110. Preferably, the pressure in the working chamber 110 does not exceed 500 Pa after the introduction of protective gases such as nitrogen, that is, the working chamber 110 is ensured to be in a vacuum nitrogen-deficient state. In this way, on the one hand, a large amount of protective gas does not need to be consumed. Compared with the traditional positive pressure high nitrogen protection, the mold 20 in the working chamber 110 is not easily damaged by high-temperature oxidation. On the other hand, heat conduction can be reduced, and heat loss to the outside of the working chamber 110 is reduced, thereby reducing the consumption of nitrogen and electric thermal energy.

[0070] Furthermore, in one embodiment, a pressure monitoring element 2113 is provided on the main gas supply pipeline 211, and each upper cover gas supply pipeline 212 is also provided with pressure monitoring elements 2125 and 2126 between the pressure regulating valve 2121 and the flow control valve 2122 and between the main control valve 2123 and the upper cover assembly 130, and a pressure monitoring element 2133 is also provided on the working chamber gas supply pipeline 213 or the working chamber 110. By providing pressure monitoring elements on the corresponding pipelines, the gas pressure in each section of the pipeline can be effectively monitored, which is convenient for timely feedback and adjustment.

[0071] The gas source device 40 may be a high-pressure nitrogen tank or other nitrogen source, the normal pressure of which is preferably not less than 15 MPa, and the purity of which is preferably above 99%.

[0072] In one embodiment, the vacuum pumping mechanism 300 has a vacuum pumping pipeline 310 and a vacuum pumping adjustment component arranged on the vacuum pumping pipeline 310. One end of the vacuum pumping pipeline 310 is used to connect with the vacuum pumping device 50, and the other end is connected with the vacuum chamber. The vacuum pumping adjustment component includes a main control valve 321 and a vacuum filter 322 connected in series. The vacuum filter 322 is closer to the vacuum chamber 121. The vacuum pumping device 50 can be a roots vacuum pump 510 or a mechanical vacuum pump 520. In the embodiment shown in the figure, the vacuum pumping device 50 is a combination of a roots vacuum pump 510 and a mechanical vacuum pump 520, wherein the mechanical vacuum pump 520 is located at the end. The vacuum pumping device 50 can also be a part of the vacuum pumping mechanism 300.

[0073] Furthermore, in one embodiment, the vacuum pumping mechanism 300 further includes a first feedback pipeline 330. One end of the first feedback pipeline 330 is in communication with the working chamber 110, and the other end is connected to the vacuum pumping pipeline 310, and the connection point is located between the main control valve 321 and the vacuum filter 322 on the vacuum pumping pipeline. The first feedback pipeline 330 is also provided with a main control valve 331.

[0074] Furthermore, in one embodiment, the vacuum pumping mechanism 300 further includes a second feedback pipeline 340. One end of the second feedback pipeline 340 is in communication with the working chamber 110, and the other end is connected to the vacuum pumping pipeline 310, and the connection point is located between the connection point between the first feedback pipeline 330 and the vacuum pumping pipeline 310 and the main control valve 321 on the vacuum pumping pipeline 310. The second feedback pipeline 340 is also provided with a main control valve 341. A buffer tank 323 and another main control valve 324 are also provided between the connection point between the vacuum pumping pipeline 310 and the first feedback pipeline 330 and the connection point between the vacuum pumping pipeline 310 and the second feedback pipeline 340.

[0075] Furthermore, in one embodiment, the vacuum pumping line 310 is divided into three sections according to the connection points between the vacuum pumping line 310 and the first feedback line 330 and the connection points between the vacuum pumping line 310 and the second feedback line 340, and each section is independently provided with an air pressure monitoring element, namely, an air pressure monitoring element 325, an air pressure monitoring element 326 and an air pressure monitoring element 327.

[0076] The above-mentioned air pressure monitoring elements can be various types of pressure gauges, which can be mechanical pressure gauges or electronic digital pressure gauges. Some air pressure monitoring elements are preferably composite pressure measuring devices according to their setting positions, such as air pressure monitoring element 2133, air pressure monitoring element 325 and air pressure monitoring element 326.

[0077] Since the working chamber 110 preferably needs to be controlled in a nitrogen protective atmosphere, in one embodiment, a pressure limiting pipeline 111 is further provided on the working chamber 110. A positive pressure limiting valve 112 is provided on the pressure limiting pipeline 111 to control the positive pressure in the working chamber 110.

[0078] In addition, in one embodiment, a sensing device is provided in the working chamber 110 to sense whether the profiling of the workpiece 30 to be processed is completed, and a display device can be provided to monitor the profiling effect of the workpiece 30 to be processed in real time.

[0079] In one embodiment, the pressure differential hot bending forming system also includes a control mechanism, which is electrically connected to the heating component 140, the driving device 150, and at least one of the main control valves, pressure regulating valves, flow control valves and pressure monitoring elements of the air supply mechanism 200, as well as corresponding components of the vacuum mechanism 300, so as to automatically control the actions of each mechanism, reduce manual operation errors, and improve production efficiency.

[0080] This embodiment also provides a pressure differential hot bending forming method, which uses the pressure differential hot bending forming system 10 of any of the above embodiments, and the pressure differential hot bending forming method includes the following steps:

[0081] The gas supply mechanism 200 is turned on to introduce protective gas into the working chamber 110, the workpiece 30 to be hot-bent is placed in the mold 20, and the mold 20 is placed on the mold installation position;

[0082] The driving device 150 is controlled to move the upper cover assembly 130 downward, and cooperates with the lower mold assembly 120 to enclose a positive pressure chamber 131;

[0083] Turning on the heating component to heat the workpiece 30 from above;

[0084] The air supply mechanism 200 and / or the vacuum mechanism 300 are turned on to form an air pressure difference between the upper and lower sides of the workpiece 30 to be processed, and non-contact hot bending is performed through the air pressure difference.

[0085] The mold 20 is preferably a porous graphite mold. The mold 20 has a specific prefabricated shape, such as Figure 5 and Figure 6 As shown, the mold 20 may have a structure such as a protrusion or a groove to obtain products with different shapes. Preferably, the lower surface of the mold 20 has a heat-conducting contact surface through which a coolant such as air or water can pass, so as to timely cool the mold 20 and the workpiece 30 or finished product thereon.

[0086] The workpiece 30 to be processed may be, but is not limited to, glass.

[0087] Preferably, before placing the mold 20, the pressure differential hot bending forming system 10 needs to be adjusted to its initial state, such as preheating the upper cover assembly 130 and the lower mold assembly 120, filling the working chamber 110 with nitrogen protection at a suitable pressure, and adjusting each main control valve, flow control valve and pressure regulating valve according to preset requirements. Preferably, after the protective gas is introduced, the pressure in the working chamber 110 does not exceed 500Pa, that is, the working chamber 110 is guaranteed to be in a vacuum nitrogen-deficient state. In this way, on the one hand, a large amount of protective gas does not need to be consumed. Compared with the traditional positive pressure high nitrogen protection, the mold 20 in the working chamber 110 is not easily damaged by high-temperature oxidation. On the other hand, heat conduction can be reduced, and the heat loss outside the working chamber 110 is reduced, thereby reducing the consumption of nitrogen and electric heat energy.

[0088] Air pressure differential hot bending generally only has an effect on the part of the workpiece 30 that has not yet been completed. Figure 4 In one embodiment, during the hot bending process, the air supply mechanism 200 and / or the vacuum mechanism 300 are opened and closed multiple times to repeatedly perform hot bending on the workpiece 30 until the expected requirements are met. Figure 4In the embodiment, the vacuuming-deflating-vacuuming action can be repeated many times according to the working mode of curve 1, the constant pressure air pressure-deflating-air pressure action can be repeated many times according to the mode of curve 2, the gradually increasing pressure air pressure-deflating-air pressure action can be repeated many times according to the mode of curve 3, or the vacuuming-air pressure-vacuuming action can be repeated many times according to the mode of curve 4. That is, the pressure differential hot bending forming system 10 can realize the application of positive pressure through the air supply mechanism 200 above the workpiece 30 to be processed, and can also be vacuumed through the vacuum mechanism 300 below the workpiece 30, or a pressure difference can be formed on the upper and lower sides of the workpiece 30 to be processed by combining the positive pressure applied by the air supply mechanism 200 with the vacuuming by the vacuum mechanism 300, so as to perform pressure differential profiling.

[0089] In addition, during the hot bending process, the air supply mechanism 200 and / or the vacuum mechanism 300 can be controlled and adjusted to form different air pressure differences on both sides of the workpiece 30 during different periods of the hot bending process. By controlling the air pressure difference on both sides of the workpiece 30 during the process, the hot bending process can be finely adjusted to further improve the quality of the product.

[0090] The pressure differential hot bending forming system 10 and the hot bending forming method use the pressure differential hot bending forming principle, and only need to set the lower mold for forming below the workpiece 30 to be processed, and form an air pressure difference on both sides of the workpiece 30 to be processed so as to bend and deform the workpiece 30 to achieve the profiling effect, while no mold is needed above the workpiece 30 to be processed, thereby reducing the use cost of the mold 20. Since only the lower mold is used, the contact between the workpiece 30 to be processed and other solid surfaces can be reduced, and the damage to the surface of the workpiece 30 to be processed during the forming process can be reduced. In addition, the problem of damage to the mold 20 caused by the traditional pressing form of upper mold-workpiece-lower mold can be avoided, thereby extending the service life of the mold 20 and further reducing the use cost of the mold 20.

[0091] The pressure differential hot bending forming system 10 and the hot bending forming method heat the top of the workpiece 30 to be processed. During the air pressure profiling process, the hot bending forming is performed through the heat conduction of the workpiece 30 to be processed itself, so that the local temperature of the workpiece 30 to be processed after the profiling action is completed is reduced through heat conduction and is no longer affected by the pressure difference of the air pressure profiling, thereby reducing the problem of scalding of the lower surface of the workpiece 30 to be processed due to lower heating in traditional forming methods. In addition, the lower surface temperature is low, which can also prevent the mold 20 from transferring surface defects to the surface of the workpiece 30 to be processed, thereby reducing the difficulty and cost of subsequent cold processing and improving the quality of the product.

[0092] Therefore, the pressure differential hot bending forming system 10 and the hot bending forming method can reduce production costs and improve product quality. They are not limited to hot bending forming of 2D glass to 3D glass and have wide application value.

[0093] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0094] The above-mentioned embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A pressure differential hot bending forming system, characterized in that: It includes an air supply mechanism, a vacuum pumping mechanism and a molding mechanism; the molding mechanism includes a working chamber, a lower mold assembly, an upper cover assembly, a heating assembly and a driving device; the air supply mechanism is connected to the working chamber to provide protective gas to the working chamber, the lower mold assembly, the upper cover assembly and the heating assembly are located in the working chamber, the lower mold assembly has a vacuum chamber and is provided with a mold mounting position for mounting the mold on the upper portion, the vacuum chamber is respectively connected to the lower portion of the mold mounting position and the vacuum pumping mechanism, the upper cover assembly is located above the lower mold assembly and can be sealed with the lower mold assembly to form a positive pressure chamber, the mold mounting position is exposed in the positive pressure chamber, the air supply mechanism is connected to the upper cover assembly to provide positive pressure gas to the positive pressure chamber through the upper cover assembly, and the heating assembly is used to heat the workpiece to be processed from above the workpiece to be processed in the mold; the driving device is connected to the upper cover assembly to drive the upper cover assembly to move toward or away from the lower mold assembly.

2. The differential pressure hot bending forming system according to claim 1, characterized in that: The lower mold assembly includes a lower mold bracket and a lower mold air guide tube mold arranged on the lower mold bracket, the lower mold bracket is sealed and connected to the bottom surface of the working chamber, the mold mounting position is arranged above the lower mold air guide tube mold, the lower part of the lower mold air guide tube mold cooperates with the lower mold bracket and the bottom surface of the working chamber to form the vacuum chamber, the vacuum chamber is connected with the lower part of the mold mounting position through the air guide holes on the lower mold air guide tube mold, and the lower mold air guide tube mold is used to seal and cooperate with the upper cover assembly.

3. The differential pressure hot bending forming system according to claim 2, characterized in that: The lower mold assembly is provided with a heat preservation assembly for heating and keeping the workpiece to be processed from below the workpiece to be processed.

4. The differential pressure hot bending forming system according to claim 3, characterized in that: The heat preservation component comprises a plurality of infrared heating tubes, and the plurality of infrared heating tubes of the heat preservation component are distributed in the lower mold air guide tube mold.

5. The differential pressure hot bending forming system according to claim 1, characterized in that: The upper cover assembly comprises an upper cover air guide tube mold and an air guide tube, one end of the air guide tube is connected to the air supply mechanism, and the other end is connected to the positive pressure chamber through the air guide hole on the upper cover air guide tube mold; The driving device is connected to the upper cover air guide tube mold, and the upper cover air guide tube mold and the lower mold assembly can be sealed and matched to enclose the positive pressure cavity.

6. The differential pressure hot bending forming system according to claim 5, characterized in that: The upper cover assembly also includes an upper cover bracket, which has a guide hole on the top, the upper cover air guide tube mold is fixed below the upper cover bracket, and a buffer gap is provided between the upper cover air guide tube mold and the upper cover bracket. The air guide tube is a corrugated tube arranged in the buffer gap and one end of which is connected to the air supply mechanism through the guide hole; the driving device is connected to the upper cover bracket.

7. The differential pressure hot bending forming system according to claim 5, characterized in that: The heating assembly comprises a plurality of infrared heating tubes, and the plurality of infrared heating tubes of the heating assembly are distributed in the upper cover air guide tube mold.

8. The differential pressure hot bending forming system according to claim 1, characterized in that: The driving device is connected to the upper cover assembly via a guide rod movably arranged above the working chamber, one end of the guide rod passes through the working chamber and is connected to the output shaft of the driving device, and the other end is connected to the upper cover assembly inside the working chamber; An air guide hole is provided in the guide rod, and the air supply mechanism is communicated with the upper cover assembly through the air guide hole of the guide rod.

9. The differential pressure hot bending forming system according to any one of claims 1 to 8, characterized in that: It also includes a porous air guide component, which is arranged below the upper cover assembly and opposite to the mold mounting position. The air supply mechanism is connected with the porous air guide component through the upper cover assembly to provide positive pressure gas to the positive pressure chamber through the porous air guide component.

10. The differential pressure hot bending forming system according to claim 9, characterized in that: The porous air-conducting component includes a porous contact heating plate and a honeycomb-type laminate. The porous contact heating plate is a porous flat-plate structure, and the honeycomb-type laminate has a honeycomb-shaped columnar pore structure. There are multiple porous contact heating plates, and adjacent porous contact heating plates are separated by the honeycomb-type laminate. The outermost two layers of the porous air-conducting component are both the porous contact heating plates.

11. The differential pressure hot bending forming system according to any one of claims 1 to 8, characterized in that: The gas supply mechanism includes a gas supply pipeline and a gas regulating component arranged on the gas supply pipeline. One end of the gas supply pipeline is used to connect to the gas source equipment, and the other end is connected to the working chamber and the upper cover assembly. The gas regulating component is used for gas supply regulation.

12. The differential pressure hot bending forming system according to claim 11, characterized in that: The gas supply pipeline includes a main gas supply pipeline, an upper cover gas supply pipeline and a working chamber gas supply pipeline. The upper cover gas supply pipeline has multiple pipelines to provide positive pressure gas with different air pressures and flow rates. One end of the main gas supply pipeline is used to connect to the gas source equipment, and the other end is connected to the multiple upper cover gas supply pipelines and the working chamber gas supply pipeline. The multiple upper cover gas supply pipelines are respectively connected to the upper cover assembly, and the working chamber gas supply pipeline is connected to the working chamber.

13. The differential pressure hot bending forming system according to claim 12, characterized in that: Along the gas flow direction in the gas supply pipeline, the gas regulating component on the main gas supply pipeline includes a main control valve and an air source filter connected in series in sequence, the gas regulating components on each of the upper cover gas supply pipelines include a pressure regulating valve, a flow control valve and a main control valve connected in series in sequence, and a buffer tank is further connected between the pressure regulating valve and the flow control valve on each of the upper cover gas supply pipelines, and the gas regulating component on the working chamber gas supply pipeline includes a flow control valve and a main control valve connected in series in sequence.

14. The differential pressure hot bending forming system according to claim 13, characterized in that: The air inlet end of the working chamber air supply pipeline is connected to the upper cover air supply pipeline for providing the minimum air pressure, and the connection point is located between the pressure stabilizing valve and the flow control valve.

15. The differential pressure hot bending forming system according to claim 13, characterized in that: An air pressure monitoring element is provided on the main air supply pipeline, and an air pressure monitoring element is also provided on each upper cover air supply pipeline between the pressure regulating valve and the flow control valve and between the main control valve and the upper cover assembly. An air pressure monitoring element is also provided on the working chamber air supply pipeline or the working chamber.

16. The differential pressure hot bending forming system according to any one of claims 1 to 8, characterized in that: The vacuum pumping mechanism comprises a vacuum pumping pipeline and a vacuum pumping regulating component arranged on the vacuum pumping pipeline. One end of the vacuum pumping pipeline is used to be connected to the vacuum pumping equipment, and the other end is communicated with the vacuum chamber. The vacuum pumping regulating component comprises a main control valve and a vacuum filter connected in series, and the vacuum filter is closer to the vacuum chamber.

17. The differential pressure hot bending forming system according to claim 16, characterized in that: It also includes a first feedback pipeline, one end of which is connected to the working chamber, and the other end is connected to the vacuum pipeline, and the connection point is located between the main control valve and the vacuum filter on the vacuum pipeline. The first feedback pipeline is also provided with a main control valve.

18. The differential pressure hot bending forming system according to claim 17, characterized in that: It also includes a second feedback pipeline, one end of which is connected to the working chamber, and the other end is connected to the vacuum pipeline, and the connection point is located between the connection point between the first feedback pipeline and the vacuum pipeline and the main control valve on the vacuum pipeline, a main control valve is also provided on the second feedback pipeline, and a buffer tank and another main control valve are also provided between the connection point between the vacuum pipeline and the first feedback pipeline and the connection point between the vacuum pipeline and the second feedback pipeline.

19. The differential pressure hot bending forming system according to claim 18, characterized in that: The vacuum pumping pipeline is divided into three sections according to the connection points between the vacuum pumping pipeline and the first feedback pipeline and the connection points between the vacuum pumping pipeline and the second feedback pipeline, and each section is independently provided with an air pressure monitoring element.

20. The differential pressure hot bending forming system according to any one of claims 1 to 8, characterized in that: A pressure-limiting pipeline is provided on the working chamber, and a positive pressure-limiting valve is provided on the pressure-limiting pipeline.

21. The differential pressure hot bending forming system according to any one of claims 1 to 8, characterized in that: It also includes a pushing component, which is arranged on the working chamber and is used to push the mold to the mold installation position or pull it out from the mold installation position.

22. A pressure differential hot bending forming method, characterized in that: Using the pressure differential hot bending forming system as described in any one of claims 1 to 21, the pressure differential hot bending forming method comprises the following steps: Open the gas supply mechanism to introduce protective gas into the working chamber, place the workpiece to be hot-bent into the mold, and place the mold on the mold installation position; Controlling the driving device to make the upper cover assembly move downward and cooperate with the lower mold assembly to enclose the positive pressure chamber; Turning on the heating component to heat the workpiece from above; The air supply mechanism and / or the vacuum mechanism are turned on to form an air pressure difference between the upper and lower sides of the workpiece to be processed, and non-contact hot bending is performed through the air pressure difference.

23. The differential pressure hot bending forming method according to claim 22, characterized in that: The protective gas introduced into the working chamber must ensure that the pressure in the working chamber does not exceed 500Pa.

24. The differential pressure hot bending forming method according to claim 22 or 23, characterized in that: During the hot bending process, the air supply mechanism and / or the vacuum mechanism are opened and closed multiple times to repeatedly perform pressure differential hot bending on the workpiece until the expected requirements are met.

25. The differential pressure hot bending forming method according to claim 24, characterized in that: The hot bending forming process also includes a step of controlling and adjusting the air supply mechanism and / or the vacuum pumping mechanism to form different air pressure differences on both sides of the workpiece at different time periods of the hot bending forming.

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