A preheating device for the upper mold of a molding machine

Abstract

This application belongs to the technical field of molding machine equipment, specifically relating to a preheating device for the upper mold of a molding machine. It includes a second drive cylinder, a guide mechanism, a push rod, a cooling plate, and heating components. The second drive cylinder drives the push rod to move up and down along the guide mechanism. The lower end of the push rod is connected to the cooling plate, and two heating components are connected below the cooling plate. The two heating components are positioned at a predetermined angle α to fit and conform to the upper surface of the irregularly shaped mold. This solution addresses the pointed or inclined features of irregularly shaped prism molds by designing two heating components distributed at a predetermined angle α. This structure allows for simultaneous heating of both sides of the mold, significantly improving heat transfer efficiency compared to conventional single-sided top heating, and resulting in more uniform heating of the mold.

Description

[Technical Field] This application belongs to the technical field of molding machine equipment, specifically relating to a preheating device for the upper mold of a molding machine. [Background Technology] Existing conventional presses are equipped with preheating or cooling pressure heads that are designed for vertical downward pressure, and their heating surfaces are typically flat. This structure is mainly suitable for processing products with regular shapes, such as circular, annular, or square aspherical or spherical lenses. However, with the diversification of optical applications, the demand for irregularly shaped optical components such as prisms is increasing. These prism products typically have five faces, and their main working faces often have specific angles. To form such products, the mold design usually corresponds to a 90-degree distributed bevel or pointed structure. For such irregularly shaped molds, existing conventional flat heating methods cannot form good surface contact with the angled pointed upper mold, often only contacting the edge part of the mold, resulting in a very small contact area. Due to poor contact, heat cannot be quickly transferred to the entire mold, resulting in excessively long preheating time and severely uneven heating of the mold, which can easily cause quality problems such as poor surface accuracy or high internal stress in the formed prism products. This cannot meet the requirements for rapid heating or precise temperature control in the cooling station. [Utility Model Content] In order to solve the problem that the planar heating method of conventional molding presses in the prior art cannot effectively fit with the upper mold of irregular molds with angles such as prisms, resulting in low heating efficiency and uneven heating, this application provides a preheating device for the upper mold of a molding press.

[0001] This application is achieved through the following technical solution: A preheating device for an upper mold of a molding press includes a second drive cylinder, a guide mechanism, a push rod, a cooling plate, and heating components. The second drive cylinder drives the push rod to move up and down along the guide mechanism. The lower end of the push rod is connected to the cooling plate. Two heating components are connected below the cooling plate. The two heating components have a predetermined angle α between them to fit and conform to the upper surface of the irregular mold.

[0002] As described above, in the upper mold preheating device of the molding press, the bottom of the cooling plate is provided with two mounting surfaces for the heating components. The two heating components are respectively mounted on the two mounting surfaces so that the bottoms of the two heating components form a predetermined angle α that is adapted to fit and adhere to the upper surface of the irregular mold.

[0003] In the above-described molding press upper mold preheating device, the driving cylinder is a low-friction adjustable stroke cylinder, and the second driving cylinder is connected to an electric proportional valve for controlling the cylinder pressure.

[0004] In the preheating device for the upper mold of the molding machine described above, the control accuracy of the electro-proportional valve is 0.005 MPa.

[0005] As described above, the upper mold preheating device of the molding machine has a guiding mechanism consisting of four sets of cross roller guides.

[0006] As described above, the upper mold preheating device of the molding machine includes a transition plate, a heat insulation plate, a heating plate, and a heat spreader plate arranged sequentially downwards from the cooling plate.

[0007] In the above-described molding press upper mold preheating device, the second drive cylinder is a triple force cylinder, a double force cylinder, or a single force cylinder.

[0008] The preheating device for the upper mold of the molding press as described above also includes a conduit connected to the cooling plate and through which thermocouple wires pass. The heating plate is provided with multiple sets of heating tubes respectively connected to the thermocouple wires.

[0009] The preheating device for the upper mold of the molding press as described above also includes a cooling water pipe connected to the cooling plate. The cooling plate has a cooling water channel inside that communicates with the cooling water pipe and is used to prevent the heating component from heating too high or too low.

[0010] In the above-described molding press upper mold preheating device, a sealing silicone sealant is provided between the thermocouple wire and the opening of the conduit.

[0011] Compared with the prior art, this application has the following advantages: 1. To address the pointed or sloping features of irregularly shaped prism molds, two heating components distributed at a predetermined angle α were designed. This structure fits snugly against the mold, enabling simultaneous heating of both sides. Compared to conventional single-sided top heating, this significantly improves heat transfer efficiency and results in more uniform heating of the mold.

[0012] 2. This device can be used not only for rapid heating in preheating stations but also for gradual cooling stations. Through auxiliary regulation of the cooling water circuit, it can prevent the heating components from overheating, thus providing a precise and gradual cooling environment during the gradual cooling stage and preventing the product temperature from dropping too quickly.

[0013] 3. It adopts a low-friction adjustable stroke cylinder in conjunction with a high-precision electric proportional valve with a precision of 0.05MPa, which can fit the mold with extremely gentle or extremely precise pressure, avoiding displacement of the mold or glass preform due to excessive pressure during the preheating stage. [Attached Image Description] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0014] Figure 1This is the front view in an embodiment of this application; Figure 2 yes Figure 1 Side view; Figure 3 yes Figure 2 An internal top view.

Detailed Implementation Methods

[0015] Please see Figures 1 to 3 A preheating device for an upper mold of a molding press includes a second drive cylinder 311, a guide mechanism 312, a push rod 313, a cooling plate 314, and heating components 315. The second drive cylinder 311 drives the push rod 313 to move up and down along the guide mechanism 312. The lower end of the push rod 313 is connected to the cooling plate 314. Two heating components 315 are connected below the cooling plate 314. The two heating components 315 have a predetermined angle α between them to fit and conform to the upper surface of the irregular mold.

[0016] In this embodiment, the device uses a second drive cylinder 311 to drive a push rod 313 to move vertically up and down along a guide mechanism 312, thereby driving the heating component 315 below to move downwards to fit the mold. Its core improvement lies in breaking the limitation that the pressure heads of conventional presses are all planar and can only press vertically. By setting two heating components 315 below the cooling plate 314 and forming a predetermined angle α between them to fit the upper surface of the irregular mold, such as a 90° angle for a prism mold, a three-dimensional heating structure that can perfectly fit the upper mold of the irregular shape is constructed. This design transforms the traditional point or line contact into a large-area surface contact, which significantly improves the heat transfer efficiency and temperature uniformity. It solves the technical problem that conventional planar heating methods cannot quickly heat irregular molds or cause uneven heating. This device can be used in a preheating station for rapid heating or in a cooling station for controlled cooling.

[0017] Furthermore, as a preferred embodiment of this solution and not a limitation, the bottom of the cooling plate 314 is provided with two mounting surfaces 3141 for mounting the heating components 315. The two heating components 315 are respectively mounted on the two mounting surfaces 3141 so that the bottom of the two heating components 315 forms a predetermined angle α that is adapted to fit and adhere to the upper surface of the irregular mold.

[0018] In this embodiment, the bottom of the cooling plate 314 is processed or designed to have two specific inclined mounting surfaces 3141. These two mounting surfaces serve as the physical carriers of the heating components 315, allowing the two independent heating components 315 mounted on them to naturally construct an inverted V-shaped or concave heating cavity with an included angle of α in space. The geometry of this cavity closely matches the raised upper surface (such as a roof ridge) of the irregularly shaped mold such as a prism to be processed. Its significant advantage lies in the fact that this three-dimensional encapsulation structure can achieve a perfect shape fit with the irregularly shaped mold, transforming the extremely inefficient point or line contact between the traditional planar heating head and the irregularly shaped mold into a large-area surface contact. This greatly improves heat transfer efficiency, ensuring uniform heating on all sides of the mold and avoiding product surface accuracy reduction or internal stress problems caused by local temperature differences. In other possible embodiments, the predetermined angle α is usually set to 90° to adapt to standard total reflection prism molds, but it can also be adjusted between 45° and 135° according to the specific geometric characteristics of the mold. The cooling plate 314 usually integrates cooling water channels, which on the one hand block the high temperature of the heating component 315 from being conducted upward to protect the drive and guide mechanism above, and on the other hand can assist in temperature adjustment during the slow cooling process, realizing a multi-functional application from rapid heating to precise temperature control.

[0019] Furthermore, as a preferred embodiment of this solution and not a limitation thereof, the drive cylinder is a low-friction adjustable stroke cylinder, and the second drive cylinder 311 is connected to an electro-proportional valve for controlling the cylinder pressure.

[0020] Furthermore, as a preferred embodiment of this solution and not a limitation, the control accuracy of the electro-proportional valve is 0.005 MPa.

[0021] In this embodiment, an electro-proportional valve is used to precisely adjust the compressed air pressure entering the second drive cylinder 311 according to the control signal. Combined with the cylinder's low friction characteristics and adjustable stroke function, this achieves flexible and precise control over the downward pressing action of the heating component 315. The beneficial effect is that the high control accuracy of the electro-proportional valve can reach 0.005MPa, allowing the bonding pressure output by the cylinder to be adjusted extremely finely. Combined with the smooth, non-creeping motion of the low-friction cylinder, this ensures good heat conduction and tightness when the heating component contacts the irregular mold, while avoiding displacement or damage to the precision mold due to excessive pressure or impact. In other possible embodiments, the specific selection of the drive cylinder includes, but is not limited to, a triple-force cylinder, a double-force cylinder, or a single-force cylinder to adapt to the process requirements of different tonnages. Moreover, this pressure control system is not only suitable for rapid heating in the preheating station, but also for the slow cooling station. By precisely controlling the bonding pressure, it assists in adjusting the cooling rate of the mold, preventing cracks in the product due to excessive temperature change.

[0022] Furthermore, as a preferred embodiment of this solution and not a limitation thereof, the guiding mechanism 312 is four sets of cross roller guides 3121.

[0023] In this embodiment, the guiding mechanism employs a four-set cross roller guide rail structure. This structure utilizes the 90-degree cross arrangement of the internal rollers, combined with the circumferential layout of the four guide rails around the push rod, enabling it to simultaneously withstand radial, anti-radial, and tangential torque loads. This strictly constrains the push rod to move only in the vertical direction. Its significant advantages include providing extremely high motion rigidity and guiding accuracy, ensuring that the push rod maintains precise verticality during lifting and lowering under the drive cylinder. This effectively prevents the lower dual heating components from tilting or wobbling when fitting the irregular mold, thus ensuring the fit and uniform force distribution between the heating components and the mold surface. In other possible embodiments, this high-rigidity guiding structure is crucial for the rapid bonding heating of the preheating station and the precise conformal cooling of the cooling station. It effectively resists lateral forces that may arise from irregular mold shapes, extending equipment lifespan and ensuring the forming quality of optical glass.

[0024] Furthermore, as a preferred embodiment of this solution and not a limitation thereof, the heating assembly 315 includes a transition plate 3151, a heat insulation plate 3152, a heating plate 3153, and a heat spreader 3154 arranged sequentially downward from the cooling plate 314.

[0025] In this embodiment, heat energy is generated by the heating tube embedded in the heating plate 3153. This heat energy is diffused and homogenized downwards through the heat spreader 3154. The excellent thermal conductivity of the heat spreader eliminates local hot spots, ensuring a highly uniform temperature distribution on the surface in contact with the irregular mold, thereby preventing internal stress in the glass preform due to uneven heating. At the same time, the heat insulation plate 3152 above the heating plate forms a heat-blocking layer, effectively inhibiting the upward conduction of high temperature to the transition plate 3151 and the cooling plate 314 above it. Together with the cooling water channel in the cooling plate, it protects the temperature-sensitive precision components such as the second drive cylinder, guide mechanism, and electro-proportional valve. Its beneficial effect is that it achieves the thermal management goal of bottom heating and top cooling, ensuring both the efficiency and uniformity of mold preheating and the long-term accuracy and stability of the equipment's motion mechanism. In other preferred embodiments, the multi-layer heating components are usually arranged in pairs and installed on the inclined surface at the bottom of the cooling plate, thereby forming a three-dimensional heating cavity with a predetermined angle (such as 90°) to perfectly fit the irregular upper surface of the prism mold for rapid preheating or precise slow cooling.

[0026] Furthermore, as a preferred embodiment of this solution and not a limitation thereof, the second drive cylinder 311 is a triple-force cylinder, a double-force cylinder, or a single-force cylinder.

[0027] In this embodiment, pneumatic actuators with different thrust levels are flexibly selected according to different process requirements, such as the required bonding pressure, mold size, or glass softening point. Single-force cylinders are the standard configuration, while double-force or triple-force cylinders output multiple times the downward pressure under the same air source pressure through internal multi-piston series connection or force amplification mechanism. Its significant advantage is that it provides a wide pressure adaptation range for the device, so that sufficient bonding driving force can be obtained even above the space-constrained molding press, ensuring that the irregular mounting surface at the bottom of the heating component can be tightly pressed against the inclined surface of the prism mold with sufficient pressure, thereby overcoming contact thermal resistance and achieving efficient heat conduction.

[0028] Furthermore, as a preferred embodiment of this solution and not a limitation, it also includes a conduit 317 connected to the cooling plate 314 and through which the thermocouple wire 316 passes, and the heating plate 3153 is provided with multiple sets of heating tubes 3155 respectively connected to the thermocouple wire 316.

[0029] In this embodiment, multiple sets of heating tubes 3155 embedded in the heating plate 3153 generate heat to rapidly heat the irregularly shaped molds such as prisms that are attached below. At the same time, thermocouple wires 316 are used to collect temperature signals in real time by penetrating deep into the core heating area. These cables are guided out to the external control system through conduits 317 that are specially connected to the cooling plate 314, thereby forming a closed-loop temperature feedback control loop. Its significant advantage is that the conduits 317 provide robust physical protection and directional guidance for the fragile temperature-sensing cables, effectively preventing the cables from getting tangled, worn, pulled, or squeezed and broken by the moving mechanism during frequent vertical lifting and attaching actions, greatly improving the reliability and safety of the equipment in long-term operation.

[0030] Furthermore, as a preferred embodiment of this solution and not a limitation, it also includes a cooling water pipe 318 connected to the cooling plate 314, wherein the cooling plate 314 has a cooling water passage 3142 that communicates with the cooling water pipe 318 and is used to prevent the heating component 315 from heating too high or too low.

[0031] In this embodiment, circulating water is introduced into the cooling water channel 3142 inside the cooling plate 314 via an external cooling water pipe 318, forming a thermal barrier between the heating component 315 and the upper drive and guide mechanism. Its significant advantage lies in achieving active regulation and protection of the thermal environment of the heating component and the overall device: on the one hand, it effectively blocks the upward conduction of the high-temperature heat generated by the heating component 315, preventing precision components such as the second drive cylinder 311, guide mechanism 312, and electro-proportional valve from failing due to overheating, ensuring the equipment's operational accuracy and lifespan; on the other hand, the cooling water channel 3142 has an auxiliary temperature control function. Especially in the slow cooling process, through the synergistic effect of water-cooled heat exchange and the heating component's heat generation, it can prevent the heating component temperature from becoming too high due to excessive thermal inertia, or provide auxiliary cooling when cooling is required to prevent the temperature from deviating from the set value, thereby precisely maintaining the mold temperature within the process-set range, i.e., preventing the temperature from being too high or too low, ensuring that the glass product cools slowly according to a predetermined curve.

[0032] Furthermore, as a preferred embodiment of this solution and not a limitation thereof, a sealing silicone sealant is provided between the thermocouple wire 316 and the opening of the conduit 317.

[0033] In this embodiment, it serves to fix the cable, and more importantly, it achieves airtight sealing of the cable routing channel, strictly preventing the leakage of protective gases such as nitrogen in the fully sealed furnace cavity through the cable gaps, thus maintaining a low-oxygen process environment. In addition, the configuration of multiple sets of heating tubes 3155 ensures that the heating components have sufficient power density to meet the rapid heating requirements of the preheating station. Combined with the accurate feedback of thermocouples, it effectively ensures the temperature uniformity of the irregular heating surface.

[0034] The working principle of this embodiment is as follows: Using a second drive cylinder connected to an electro-proportional valve with a control precision of up to 0.005MPa as a power source, the drive rod moves up and down along a vertical path defined by four sets of intersecting roller guides, thereby causing the lower cooling plate and two heating components connected below the cooling plate to move downwards. To adapt to the special shapes of irregular molds such as prisms, the two heating components are respectively mounted on two inclined mounting surfaces at the bottom of the cooling plate, forming a predetermined angle α (e.g., 90°) between them to fit and conform to the upper surface of the irregular mold, thus enabling a three-dimensional wrapping fit of the upper mold. During operation, the heating components... The heating plate inside the component generates heat through heating tubes, which is then evenly transferred to the mold surface via a heat spreader. Thermocouple wires are led out through sealed conduits and provide temperature feedback signals to achieve closed-loop temperature control. At the same time, circulating water is introduced into the cooling water circuit inside the cooling plate. This serves two purposes: firstly, it acts as a heat insulation barrier, preventing the high temperature generated by the heating components from being conducted upwards to protect the cylinder and guide mechanism; secondly, it plays an auxiliary role in temperature control during the slow cooling process, preventing the heating temperature from being too high or too low, thus meeting the process requirements of rapid heating in the preheating station or precise cooling control in the slow cooling station.

[0035] The above are implementation methods provided in conjunction with specific content, and it is not intended that the specific implementation of this application is limited to these descriptions. Any methods or structures that are similar to those of this application, or any technical deductions or substitutions made based on the concept of this application, should be considered within the scope of protection of this application.

Claims

1. A preheating device for the upper mold of a molding machine, characterized in that, The device includes a second drive cylinder (311), a guide mechanism (312), a push rod (313), a cooling plate (314), and a heating assembly (315). The second drive cylinder (311) drives the push rod (313) to move up and down along the guide mechanism (312). The lower end of the push rod (313) is connected to the cooling plate (314). Two heating assemblies (315) are connected below the cooling plate (314). The two heating assemblies (315) have a predetermined angle α between them to fit and conform to the upper surface of the irregular mold.

2. The preheating device for the upper mold of the molding machine according to claim 1, characterized in that, The bottom of the cooling plate (314) is provided with two mounting surfaces (3141) for the heating components (315). The two heating components (315) are respectively mounted on the two mounting surfaces (3141) so that the bottom of the two heating components (315) forms a predetermined angle α that is adapted to fit the upper surface of the irregular mold.

3. The molding machine upper mold preheating device according to claim 1, characterized in that, The drive cylinder is a low-friction adjustable stroke cylinder, and the second drive cylinder (311) is connected to an electric proportional valve for controlling the cylinder pressure.

4. The molding machine upper mold preheating device according to claim 3, characterized in that, The control accuracy of the electro-proportional valve is 0.005 MPa.

5. The molding machine upper mold preheating device according to claim 1, characterized in that, The guiding mechanism (312) consists of four sets of cross roller guides (3121).

6. The molding machine upper mold preheating device according to claim 1, characterized in that, The heating assembly (315) includes a transition plate (3151), a heat insulation plate (3152), a heating plate (3153), and a heat spreader (3154) arranged sequentially downward from the cooling plate (314).

7. The molding machine upper mold preheating device according to claim 1, characterized in that, The second drive cylinder (311) is a triple force cylinder, a double force cylinder, or a single force cylinder.

8. The molding machine upper mold preheating device according to claim 6, characterized in that, It also includes a conduit (317) connected to the cooling plate (314) and through which the thermocouple wire (316) passes, and the heating plate (3153) is provided with multiple sets of heating tubes (3155) respectively connected to the thermocouple wire (316).

9. The molding machine upper mold preheating device according to claim 1, characterized in that, It also includes a cooling water pipe (318) connected to the cooling plate (314), and the cooling plate (314) has a cooling water channel (3142) inside that communicates with the cooling water pipe (318) and is used to prevent the heating component (315) from heating too high or too low.

10. The molding machine upper mold preheating device according to claim 8, characterized in that, A sealing silicone sealant is provided between the thermocouple wire (316) and the opening of the conduit (317).

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