A mandrel internal heating and curing mold, apparatus and curing method suitable for composite material forming processes

Abstract

A kind of core shaft inner heating curing mould, device and curing method suitable for composite material forming process belong to composite material technical field, solve the problems of uneven heating, low heating efficiency, complex mould maintenance and low temperature control precision of inner heating curing device mould.The mould includes: mould barrel, front end shaft assembly, intermediate connecting pipe assembly, rear end shaft assembly, temperature measuring assembly, current collector ring, expansion sleeve, heating pipe and bolt;The mould barrel is sleeved on the outside of the intermediate connecting pipe assembly;The front end shaft assembly and rear end shaft assembly are connected with the two ends of intermediate connecting pipe assembly by bolt respectively;The temperature measuring assembly passes through the axis of rear end shaft assembly and is inserted into the pipe core of intermediate connecting pipe assembly;The current collector ring is sleeved on the rear end shaft assembly;The heating pipes are uniformly distributed around the intermediate connecting pipe;The expansion sleeve is used to fasten the rear end shaft assembly and the mould barrel.The present application is suitable for curing scene in composite material production.

Description

Technical Field

[0001] This invention belongs to the field of composite material technology, specifically relating to a composite material curing and molding technology. Background Technology

[0002] Current internal heating curing devices suffer from structural limitations. Only one heating tube can be inserted into each side of the mold, and the lack of internal convection leads to uneven heating and temperature differences on the mold surface. The low total heating power of only two heating tubes results in slow heating speed and low efficiency. The mold shaft is welded to the mold body, making replacement difficult and hindering mold maintenance. Temperature sensors cannot be installed, and heating temperature is controlled by heating time and thermal resistance. Temperature differences on the mold surface can cause inconsistent curing of fiber-wound composite materials, degrading product performance and potentially rendering the product unusable. Low total heating power also results in low production efficiency. Furthermore, the difficulty in mold maintenance hinders continuous production. The inability to install temperature sensors and reliance on heating time and thermal resistance for precise temperature control, coupled with the varying temperatures required at different curing stages, makes the device unsuitable for the required production processes. Summary of the Invention

[0003] This invention provides a mandrel-based internal heating curing mold, device, and method suitable for composite material molding processes. Its purpose is to solve the problems of uneven mold heating, low heating efficiency, complex mold maintenance, and low temperature control accuracy of existing internal heating curing devices.

[0004] The mandrel-in-heat curing mold suitable for composite material molding processes according to the present invention includes: Mold body, front shaft assembly, intermediate connecting pipe assembly, rear shaft assembly, temperature measuring assembly, slip ring, expansion sleeve, heating tube and bolts; The front end shaft assembly and the rear end shaft assembly are respectively connected to both ends of the intermediate connecting pipe assembly by bolts, and the three are coaxial. The mold cylinder is fitted over the outside of the intermediate connecting pipe assembly, and both ends of the mold cylinder extend and cover the positions where the front end shaft assembly and the rear end shaft assembly are connected to the intermediate connecting pipe assembly. The rear end shaft assembly and the mold cylinder are fastened together by the expansion sleeve. The temperature measuring component is inserted into the core of the intermediate connecting tube assembly through the axis of the rear shaft assembly, and is used to detect the temperature inside the core of the intermediate connecting tube assembly. The slip ring is sleeved on the rear shaft assembly; The heating tubes are evenly distributed on the outer wall of the intermediate connecting tube assembly.

[0005] Furthermore, a preferred embodiment is provided: the intermediate connecting pipe assembly includes: a connecting pipe and several fixing brackets, the several fixing brackets being sleeved on the connecting pipe for fixing the heating pipe.

[0006] Furthermore, a preferred embodiment is provided: several air guide holes are evenly provided in the area near both ends of the sidewall of the connecting pipe.

[0007] Furthermore, a preferred embodiment is provided: the fixing frame includes: a tripod, blades, and set screws; The tripod has a through hole at its center, and a heating tube mounting hole is provided at each of the three vertices of the tripod. Each heating tube mounting hole has a set screw hole on its side wall. There are three blades, which are fixed at the middle positions of the three sides of the tripod. The angle between the plane of the blade and the plane of the tripod is greater than 5° and less than 15°.

[0008] Furthermore, a preferred embodiment is provided: the number of heating tubes is 3, which are respectively installed in the three heating tube mounting holes of the tripod and fixed by the set screws.

[0009] Furthermore, a preferred embodiment is provided: the temperature measuring component includes a thermocouple and a fixing component, wherein the fixing component is used to fix the thermocouple.

[0010] Furthermore, a preferred embodiment is provided: the fixing component includes: a bearing sleeve, a thermocouple sleeve, a bearing, and an elastic retaining ring for the bore; The thermocouple sleeve is fitted onto the thermocouple, and a bearing is installed on each side of the thermocouple sleeve. The bearing sleeve is fitted onto the outside of the thermocouple sleeve, and the hole is secured with an elastic retaining ring.

[0011] Furthermore, a preferred embodiment is provided: the thermocouple is inserted into the intermediate connecting tube assembly to detect the temperature inside the intermediate connecting tube assembly.

[0012] The present invention proposes a mandrel internal heating and curing device suitable for composite material winding molding process, comprising: internal heating and curing mold, power supply and temperature control box; The internal heating and curing mold is the mandrel internal heating and curing mold suitable for composite material winding molding process described above; The thermocouple of the internal heating curing mold sends the collected temperature information to the temperature control box. The power source provides a working power signal to the slip ring of the internal heating and curing mold.

[0013] This invention proposes a mandrel-in-mold heating and curing method for composite material winding molding, which uses the aforementioned mandrel-in-mold heating and curing device suitable for composite material winding molding to perform curing. The steps include: The predetermined temperature of the internal heating curing mold is set by the power supply and temperature control box; Power is cut off when the temperature monitored by the thermocouple reaches the preset temperature.

[0014] Compared with existing technologies, the advantages of this invention are: The mandrel internal heating and curing device proposed in this invention solves the problems of uneven heating and low heating efficiency of internal heating and curing devices by using three conventional heating pipes and blades to circulate hot air. By using thermocouples and a temperature control box, the heating temperature is controlled in a closed loop, solving the problem of poor temperature control accuracy. By using an expansion sleeve to connect the cylinder body and the mold end shaft assembly, the maintenance of the entire device is more convenient, thereby improving the production efficiency and pass rate of the entire high-temperature curing fiber winding molding composite material, and also making it more conducive to equipment maintenance in the entire high-temperature curing fiber winding molding composite material production process.

[0015] This invention is applicable to curing scenarios during composite material production. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the internal heating mold described in Embodiment 1, wherein 1-1 is the mold cylinder, 1-2 is the front end shaft assembly, 1-3 is the intermediate connecting pipe assembly, 1-4 is the rear end shaft assembly, 1-5 is the temperature measuring assembly, 1-6 is the slip ring, 1-7 is the expansion sleeve, 1-8 is the heating pipe, and 1-9 is the bolt. Figure 2 This is a schematic diagram of the structure of the mold cylinder 1-1 as described in Embodiment 1; Figure 3 This is a schematic diagram of the structure of the mold front end shaft assembly 1-2 as described in Embodiment 1; Figure 4 This is a schematic diagram of the intermediate connecting pipe assembly 1-3 as described in Embodiment 2; Figure 5 This is a schematic diagram of the connecting pipe 1-3-1 as described in Embodiment 2; Figure 6 This is a schematic diagram of the structure of blade 1-3-2 as described in Embodiment 2; Figure 7 This is a schematic diagram of the installation position of the set screw 1-3-3 as described in Embodiment 2; Figure 8 This is a schematic diagram of the structure of the mold rear shaft assembly 1-4 as described in Embodiment 1; Figure 9 The diagram shows the structure of the temperature measuring component 1-5 as described in Embodiment 3. In the diagram, 1-5-1 is a thermocouple, 1-5-2 is a bearing sleeve, 1-5-3 is a thermocouple sleeve, 1-5-4 is a bearing, and 1-5-5 is an elastic retaining ring for the hole. Figure 10 This is a schematic diagram of the structure of the collector rings 1-6 as described in Embodiment 1; Figure 11 This is a schematic diagram of the structure of the expansion sleeve 1-7 as described in Embodiment 1; Figure 12 This is a schematic diagram of a mandrel-based internal heating and curing device suitable for composite material molding processes, as described in Embodiment 5. In this diagram, 1 is an internal heating and curing mold, 2 is a temperature control box, 3 is a thermocouple signal line, and 4 is a power supply line. Detailed Implementation

[0017] The technical solutions of the embodiments of the present invention will now be clearly and completely described with reference to the accompanying drawings. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0018] Implementation Method 1 Reference Figure 1 , Figure 2 , Figure 3 , Figure 8 , Figure 10 , Figure 11 This implementation method is described below.

[0019] The mandrel-in-mold heating and curing mold suitable for composite material winding molding process described in this embodiment includes: Mold cylinder 1-1, front end shaft assembly 1-2, intermediate connecting pipe assembly 1-3, rear end shaft assembly 1-4, temperature measuring assembly 1-5, slip ring 1-6, expansion sleeve 1-7, heating tube 1-8 and bolt 1-9; The mold cylinder 1-1 is fitted over the outside of the intermediate connecting pipe assembly 1-3; The front end shaft assembly 1-2 and the rear end shaft assembly 1-4 are respectively connected to the two ends of the intermediate connecting pipe assembly by bolts 1-9; The temperature measuring component 1-5 is inserted into the core of the intermediate connecting tube component 1-3 through the axis of the rear shaft component 1-4; The collector rings 1-6 are sleeved on the rear shaft assembly 1-4; The heating tube 1-8 is closely attached to the intermediate connecting tube assembly 1-3; The expansion sleeve 1-7 is used to fasten the rear shaft assembly 1-4 and the mold cylinder 1-1.

[0020] Specifically: such as Figure 1 As shown, the mold body 1-1 of the internal heating curing mold has an inner hole mating surface machined at both ends, and the inner hole mating surface is adapted to the inner hole of the expansion sleeve 1-7.

[0021] like Figure 3 , Figure 8 As shown, the front shaft assembly 1-2 and the rear shaft assembly 1-4 are machined with outer circular mating surfaces, which are used to fit with the inner hole of the expansion sleeve 1-7. The rear shaft assembly 1-4 is also machined with a keyway, which is used to connect with the slip ring 1-6 by a key.

[0022] Implementation Method 2 Reference Figure 4 , Figure 5 , Figure 6 , Figure 7 This implementation method is described below.

[0023] This embodiment is a further illustrative example of the intermediate connecting tube assembly 1-3 in a mandrel-in-heat curing mold suitable for composite material winding molding process as described in Embodiment 1.

[0024] The intermediate connecting pipe assembly 1-3 described in this embodiment includes: a connecting pipe 1-3-1 and several fixing brackets, which are sleeved on the connecting pipe 1-3-1 and used to fix the heating pipe 1-8.

[0025] The connecting pipe 1-3-1 has several air guide holes evenly distributed at both ends, and two mounting holes at the outermost end, which are used to connect the front shaft assembly 1-2 and the rear shaft assembly 1-4, respectively.

[0026] The fixing frame includes: a tripod, blade 1-3-2 and set screw 1-3-3; The tripod has a through hole in the center, three heating tube mounting holes around it, and three set screw holes on the side. There are three blades 1-3-2, which are evenly distributed on the tripod.

[0027] There are three heating tubes 1-8, which are installed in the three heating tube mounting holes of the tripod and fixed by the set screws 1-3-3.

[0028] Specifically: In this embodiment, the two ends of the connecting pipe 1-3-1 are respectively machined with multiple large-diameter air guide holes and two mounting holes; the tripod is machined with a large central hole, and three heating tube 1-8 mounting holes and three set screw holes arranged in an equilateral triangle are machined on the outer side. Three fan-shaped blades 1-3-2 are installed on the outermost side. The connecting pipe 1-3-1 and the four fixing brackets together form the intermediate connecting pipe assembly 1-3.

[0029] Implementation Method 3 Reference Figure 9 This implementation method is described below.

[0030] This embodiment is a further illustrative example of the temperature measuring components 1-5 in a mandrel-in-heat curing mold suitable for composite material winding molding process as described in Embodiment 1.

[0031] The temperature measuring components 1-5 described in this embodiment include: thermocouple 1-5-1 and fixing components.

[0032] The fixing assembly includes: bearing sleeve 1-5-2, thermocouple sleeve 1-5-3, bearing 1-5-4, and elastic retaining ring for the hole 1-5-5; The thermocouple sleeve 1-5-3 is fitted onto the thermocouple 1-5-1. A bearing 1-5-4 is installed on each side of the thermocouple sleeve 1-5-3. The bearing sleeve 1-5-2 is fitted onto the outside of the thermocouple sleeve 1-5-3. The hole is fixed with an elastic retaining ring 1-5-5. The working end of the thermocouple 1-5-1 is inserted into the intermediate connecting tube assembly (1-3).

[0033] Specifically: In this embodiment, a bearing 1-5-4 is installed on each side of the thermocouple sleeve 1-5-3, then the bearing sleeve 1-5-2 is installed, and then the elastic retaining ring 1-5-5 is used to fix it. Finally, the thermocouple 1-5-1 is installed to form the temperature measuring assembly 1-5.

[0034] Implementation Method 4 This embodiment is an example illustration of an installation method for a mandrel-in-heat curing mold suitable for composite material winding molding process, as described in any one of Embodiments 1 to 3.

[0035] When installing the internally heated curing mold: Step 1: Insert the three heating tubes 1-8 into the intermediate connecting tube assembly 1-3 and fix them with the set screw 1-3-3; Step 2: Install and fix the front end shaft assembly 1-2 and the rear end shaft assembly 1-4 at both ends of the intermediate connecting pipe assembly 1-3 using the bolts 1-9 respectively; Step 3: Insert the assembled components from Step 2 into the mold cylinder 1-1; Step 4: Use expansion sleeve 1-7 to install and fix the mold cylinder 1-1 to the front end shaft assembly 1-2 and the rear end shaft assembly 1-4, and adjust their coaxiality; Step 5: Install the slip rings 1-6 onto the rear shaft assembly 1-4; Step 6: Insert the temperature measuring components 1-5 into the end of the rear shaft assembly 1-4 to form an internal heating and curing mold.

[0036] Implementation Method 5 Reference Figure 12This implementation method is described below.

[0037] The mandrel internal heating and curing device for composite material winding molding process described in this embodiment includes: internal heating and curing mold 1, power supply, temperature control box 2, thermocouple signal line 3 and power line 4. The internal heating and curing mold 1 is a mandrel internal heating and curing mold suitable for composite material winding molding process, as described in any one of Embodiments 1 to 3. The thermocouple 1-5-1 of the internal heating curing mold 1 is connected to the power supply and temperature control box 2 through the thermocouple signal line 3; The collector rings 1-6 of the internal heating curing mold 1 are connected to the power source via the power line 4.

[0038] The following is a detailed introduction to the usage of this device: When using this device, the predetermined temperature of the internal heating curing mold 1 is first set through the power supply and temperature control box 2. The internal heating curing mold 1 rotates to increase its temperature. The thermocouple 1-5-1 on the mold, because it is equipped with double bearings, does not rotate with the mold, thus preventing the thermocouple signal wire 3 from being twisted. As the mold rotates, the blades 1-3-2 on its internal fixed frame begin to drive the hot air between the mold cylinder 1-1 and the connecting pipe 1-3-1, transporting it from one end to the other. The hot air then enters the connecting pipe 1-3-1 through the air guide hole at one end of the connecting pipe 1-3-1. Under the action of the air pressure difference, the hot air circulates to the other end of the connecting pipe 1-3-1 and is discharged, ultimately forming circulating hot air. This ensures that the mold cylinder 1-1 is heated evenly and minimizes the surface temperature difference of the mold cylinder 1-1, with a maximum temperature difference not exceeding 5°C. When the temperature monitored by the thermocouple 1-5-1 reaches the preset temperature, the power is cut off, and the heating tube 1-8 stops heating.

[0039] The original internal heating mold has a maximum heating power of 8KW, a heating rate of 2~3℃ / min, and takes about 50 minutes to reach the operating temperature. The temperature control accuracy is ±15℃.

[0040] This embodiment uses three 8-meter-long heating tubes 1-8, with a maximum heating power of 24KW and a heating rate of 8~10℃ / min. Furthermore, due to the use of thermocouples 1-5-1 and a closed-loop temperature control system (power supply and temperature control box 2), the temperature control accuracy can reach ±5℃. After the winding process is complete, the mold can also be used as a regular mold in a curing oven for further curing of the product.

[0041] Implementation Method Six The mandrel-in-curing method for composite material winding molding described in this embodiment uses the mandrel-in-curing device suitable for composite material winding molding described in Embodiment 5 for curing, and the steps include: The predetermined temperature of the internal heating curing mold 1 is set by the power supply and temperature control box 2; Power is cut off when the temperature monitored by thermocouple 1-5-1 reaches the preset temperature.

Claims

1. A mandrel-in-mold for heating and curing suitable for composite material winding molding processes, characterized in that, The mold includes: mold body (1-1), front end shaft assembly (1-2), middle connecting pipe assembly (1-3), rear end shaft assembly (1-4), temperature measuring assembly (1-5), slip ring (1-6), expansion sleeve (1-7), heating tube (1-8), and bolt (1-9); The front end shaft assembly (1-2) and the rear end shaft assembly (1-4) are respectively connected to both ends of the intermediate connecting pipe assembly (1-3) by bolts (1-9), and the three are coaxial; The mold cylinder (1-1) is fitted over the outside of the intermediate connecting pipe assembly (1-3), and both ends of the mold cylinder (1-1) extend and cover the positions where the front end shaft assembly (1-2) and the rear end shaft assembly (1-4) are connected to the intermediate connecting pipe assembly (1-3). The rear end shaft assembly (1-4) and the mold cylinder (1-1) are fastened together by the expansion sleeve (1-7). The temperature measuring component (1-5) is inserted into the core of the intermediate connecting tube assembly (1-3) through the axis of the rear shaft assembly (1-4) to detect the temperature inside the core of the intermediate connecting tube assembly (1-3). The slip ring (1-6) is sleeved on the rear shaft assembly (1-4); The heating tubes (1-8) are evenly distributed on the outer side wall of the intermediate connecting tube assembly (1-3); The intermediate connecting pipe assembly (1-3) includes a connecting pipe (1-3-1) and several fixing brackets, which are sleeved on the connecting pipe (1-3-1) and used to fix the heating pipe (1-8). The sidewall of the connecting pipe (1-3-1) near both ends is provided with several air guide holes evenly distributed; The fixing frame includes: a tripod, a blade (1-3-2), and a set screw (1-3-3). The tripod has a through hole at its center, and a heating tube mounting hole is provided at each of the three vertices of the tripod. Each heating tube mounting hole has a set screw hole on its side wall. There are three blades (1-3-2), which are fixed at the middle positions of the three sides of the tripod. There are three heating tubes (1-8), which are installed in the three heating tube mounting holes of the tripod and fixed by the set screw (1-3-3).

2. The mandrel-in-mold heating and curing mold suitable for composite material winding molding process according to claim 1, characterized in that, The angle between the plane containing the blade (1-3-2) and the plane containing the tripod is greater than 5° and less than 15°.

3. A mandrel-in-mold for heating and curing in composite material winding molding process according to claim 1, characterized in that, The temperature measuring component (1-5) includes a thermocouple (1-5-1) and a fixing component, wherein the fixing component is used to fix the thermocouple (1-5-1).

4. A mandrel-in-mold for heating and curing in a composite material winding process according to claim 3, characterized in that, The fixing components include: bearing sleeve (1-5-2), thermocouple sleeve (1-5-3), bearing (1-5-4), and elastic retaining ring for the hole (1-5-5). The thermocouple sleeve (1-5-3) is fitted onto the thermocouple (1-5-1). A bearing (1-5-4) is installed on each side of the thermocouple sleeve (1-5-3). The bearing sleeve (1-5-2) is fitted onto the outside of the thermocouple sleeve (1-5-3). The hole is secured with an elastic retaining ring (1-5-5) to fix the bearing sleeve (1-5-2).

5. A mandrel-in-mold for heating and curing in composite material winding molding process according to claim 3, characterized in that, The thermocouple (1-5-1) is inserted into the intermediate connecting tube assembly (1-3) to detect the temperature inside the intermediate connecting tube assembly (1-3).

6. A mandrel-in-mold heating and curing device suitable for composite material winding molding process, characterized in that, The device includes: an internal heating curing mold (1), a power supply and a temperature control box (2); The internal heating curing mold (1) is a mandrel internal heating curing mold suitable for composite material winding molding process according to any one of claims 1-5; The thermocouple (1-5-1) of the internal heating curing mold (1) sends the collected temperature information to the temperature control box (2); The power source provides a working power signal to the collector ring of the internal heating curing mold (1).

7. A method for in-mandrel heating and curing in a composite material winding molding process, characterized in that, The curing process is carried out using a mandrel-in-mold heating and curing device as described in claim 6, which is suitable for composite material winding molding. The steps include: The predetermined temperature of the internal heating curing mold (1) is set by the power supply and temperature control box (2); Power is cut off when the temperature monitored by thermocouple (1-5-1) reaches the preset temperature.

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