Quick-change mold system for carbon fiber steering wheel compression molding

Abstract

This invention relates to a carbon fiber steering wheel compression molding die, specifically a quick-change die system for carbon fiber steering wheel compression molding. It includes a heating module and a molding module. The molding module comprises multiple molding sub-dies, the number of which is the same as the number of parts of the steering wheel to be molded. Each molding sub-die only covers the parts of the steering wheel to be molded, with the remaining parts of the steering wheel extending from their ports. Each port of the molding sub-die has a limiting clip for fixing the steering wheel frame. The heating module includes multiple heating elements spaced apart. Each heating element has a cavity into which the molding sub-dies can be embedded. Each heating element includes a heating base and a heating cover. The heating module also includes a positioning module for fixing the steering wheel. The quick-change die system for carbon fiber steering wheel compression molding using this solution has the advantages of low die replacement cost, high productivity, and good product quality.

Description

Technical Field

[0001] This invention relates to a carbon fiber steering wheel compression molding die, and more specifically to a quick-change die system for carbon fiber steering wheel compression molding. Background Technology

[0002] Currently, carbon fiber steering wheels for ordinary passenger vehicles typically use genuine leather / suede at the 3 and 9 o'clock positions (grip area), and carbon fiber at the 6 o'clock (lower rim) and 12 o'clock (upper rim). The mainstream molding processes for carbon fiber steering wheels include compression molding, autoclave molding, hot press molding, and hand lay-up molding.

[0003] Among the existing mainstream molding processes: Compression molding: (1) The upper and lower molds usually have built-in heating mechanisms or are heated by the press itself. After the mold completes the curing cycle of a product, it needs to be cooled as a whole before it can be opened and the part removed. Then, a new part is put into the mold and the whole is heated to the high temperature required for the next molding cycle. The typical molding heat preservation time is 45 minutes, of which heating and cooling each account for about 15-20 minutes, and the effective molding time accounts for only about half. This repeated heating and cooling process consumes a lot of time and energy, which seriously restricts productivity. (2) A new mold must be designed for a new steering wheel, which prolongs the new product launch cycle and requires a large capital investment. (3) Since the mold is fixed to the press, when the mold is closed, yarn is easily caught at the parting surface, which causes the carbon fiber texture at the parting line to be damaged.

[0004] Autoclave process: (1) After the autoclave is put into the mold, the molding time usually takes more than 2 hours to allow the carbon fiber prepreg to cure completely, resulting in low production efficiency. (2) Autoclave equipment is expensive, energy-intensive, has a long cycle time per piece, and requires a lot of auxiliary materials. It is suitable for complex curved surfaces and large parts, but not suitable for large-volume, low-priced small parts. (3) For some steering wheel body foam products that are not resistant to high temperatures, due to the overall heating characteristics of the autoclave, the foam or rubber and other base materials in the area not covered by the mold will undergo secondary expansion or deformation, resulting in product scrap.

[0005] Hand lay-up molding (also known as "wet carbon") is commonly used in the aftermarket, but its overall weight, appearance, production efficiency, and surface quality are entirely dependent on the worker's skills and cannot be adapted to large-scale production by enterprises. Summary of the Invention

[0006] The present invention aims to provide a quick-change mold system for molding carbon fiber steering wheels, which can avoid the energy waste and low efficiency caused by repeated heating and cooling in the existing process.

[0007] The quick-change mold system for carbon fiber steering wheel compression molding in this solution includes a heating module and a molding module. The molding module comprises multiple sets of molding sub-molds, the number of which is the same as the number of parts of the steering wheel to be molded. Specifically, if there are two parts of the steering wheel to be molded, there are also two sets of molding sub-molds. Each molding sub-mold only covers the parts of the steering wheel to be molded, with the rest of the steering wheel extending from the port of the molding sub-mold. A limiting card is provided at the port of the molding sub-mold to ensure that a closed cavity is formed after the molding sub-mold is closed. Since the molding sub-mold only processes the parts of the steering wheel that need to be processed, the molding sub-mold is small in size and can be individually applied and closed; moreover, the mold closing line can be visually inspected to ensure that no yarn is caught during mold closing, resulting in high production flexibility. The heating module includes multiple heating sections spaced apart to avoid areas of the steering wheel with low heat resistance. Each heating section has a cavity that can be embedded in the molding sub-mold, and each heating section includes a heating base and a heating cover. As a high-value, universal component, the heating module can be shared with multiple molding modules. Different steering wheel models only differ in the mold cavity of the molding sub-mold. Therefore, the heating module eliminates the need for a molding cooling cycle, significantly increasing production capacity while reducing heat loss; it also improves energy efficiency, aligning with the principles of green manufacturing. The heating module also includes a positioning module for fixing the steering wheel, thereby fixing the relative position of the steering wheel and the molding sub-mold, ensuring a high product yield.

[0008] Furthermore, it also includes a heat insulation panel that covers the exterior of the heating module. This further reduces heat loss and improves energy efficiency.

[0009] Furthermore, the cavity is located on the heating base, and the sidewalls of the cavity are angled, with the cavity gradually widening from the bottom to the opening. The outer wall of the molding sub-mold is angled to match the cavity, facilitating the replacement and placement of the molding sub-mold.

[0010] Furthermore, both the heating cover and the heating base are equipped with heating oil circuits; the heating oil circuits of the multiple heating covers are connected by external oil pipes; and the heating oil circuits of the multiple heating bases are interconnected loops.

[0011] Furthermore, the heating cover is connected and fixed via a connecting plate; the heating module also includes a pressure boosting module, one end of which is fixedly connected to the connecting plate, and the other end can abut against the steering wheel. The design of the limiting module, combined with the downward pressure of the pressure boosting module, ensures that the position and quality of each molded product are highly consistent, significantly improving the product qualification rate and quality stability.

[0012] Furthermore, a slot is provided at the port of the forming sub-mold, and the limiting card is engaged in the slot. Because some workpiece structures have narrow reserved gaps, the limiting card is relatively thin and easily damaged during installation and removal. Therefore, it is designed as a replaceable structure with a slot connection.

[0013] Furthermore, it also includes a handle, which is disposed on the heating module.

[0014] Furthermore, the heating cover is also provided with a relief groove corresponding to the spokes.

[0015] The advantages of this invention are: 1) It uses replaceable molding sub-molds, and the heating module is kept at the working temperature for a long time without the need for heating or cooling, achieving near-continuous production. Compared with traditional processes, energy consumption is reduced by 30-40%, significantly improving production efficiency and energy utilization; 2) Since the molding sub-mold only covers the steering wheel to be molded, it is small and lightweight, and can be easily replaced manually or with a regular robotic arm, avoiding the problems of traditional molds requiring forklifts or other large equipment for transportation and cumbersome operation due to their heavy weight; 3) The clearance between molding sub-molds and heating parts prevents excessive heat radiation to the foaming area during molding, eliminating the problem of secondary expansion or deformation of the foam layer; 4) There is no yarn trapping, the carbon fiber texture at the mold parting line is complete, and the appearance after molding is aesthetically pleasing; 5) The heating base, as a high-value universal component, can be shared by multiple low-cost molding modules. When developing new products, only molding and positioning modules matching the new product need to be designed and manufactured, reducing mold development costs by more than 50%. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the quick-change mold system for carbon fiber steering wheel compression molding according to the present invention. Figure 2 This is an internal structural diagram of the quick-change mold system for molding carbon fiber steering wheels according to the present invention; Figure 3 This is a schematic diagram of the structure of the heating cover in the quick-change mold system for molding carbon fiber steering wheels according to the present invention. Figure 4 This is a schematic diagram illustrating the use of the molding sub-mold in the quick-change mold system for carbon fiber steering wheel compression molding according to the present invention. Figure 5 This is a schematic diagram of the heating base in the quick-change mold system for molding carbon fiber steering wheels according to the present invention; Figure 6 This is a structural diagram of the molding sub-mold in the quick-change mold system for molding carbon fiber steering wheels according to the present invention.

[0017] In the diagram, 1-1 is the forming sub-mold, 1-11 is the upper mold, 1-12 is the lower mold, 1-2 is the slot, 1-3 is the limiting card, 2 is the heating part, 2-1 is the heating base, 2-2 is the heating cover, 2-3 is the cavity, 2-4 is the connecting plate, 2-5 is the heating oil circuit, 3 is the positioning block, 4 is the elastic rubber, 5 is the heat insulation plate, 6 is the handle, 7 is the steering wheel, and 7-1 is the steering wheel frame. Detailed Implementation

[0018] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments: according to Figures 1 to 6 As shown, this solution provides a quick-change mold system for molding carbon fiber steering wheels, including a heating module and a molding module. The molding module includes multiple molding sub-molds 1-1, the number of which is the same as the number of areas to be molded on the steering wheel 7. Since the carbon fiber steering wheels 7 of ordinary passenger vehicles typically use a six-point (lower rim) and twelve-point (upper rim) carbon fiber structure, meaning the steering wheel 7 has two areas to be molded, this embodiment has two sets of molding sub-molds 1-1. The molding sub-mold 1-1 only covers the six-point (lower rim) and twelve-point (upper rim) areas of the steering wheel; the remaining part of the steering wheel 7 extends from the port of the molding sub-mold 1-1. A limiting card 1-3 is provided at the port of the molding sub-mold 1-1. This limiting card 1-3 has a locking slot adapted to the steering wheel frame, so that after the molding sub-mold 1-1 is closed, its mold cavity is a closed cavity.

[0019] The number of heating elements 2 is the same as the number of molding sub-molds 1-1, such as... Figure 2 , Figure 3 As shown, the heating module includes two heating sections 2, spaced apart to avoid the foam layers at the three o'clock and nine o'clock positions (hand grip areas) of the steering wheel. Each heating section 2 has a cavity 2-3 into which a molding sub-mold 1-1 can be embedded. Specifically, each heating section 2 includes a heating base 2-1 and a heating cover 2-2. The cavity 2-3 is located on the heating base 2-1, and its sidewalls are angled, gradually widening from the bottom upwards. The outer wall of the molding sub-mold 1-1 has an angle adapted to match the cavity 2-3, facilitating the pulling out and insertion of the molding sub-mold 1-1.

[0020] The heating module also includes a positioning module for fixing the steering wheel frame. In this embodiment, positioning block 3 is preferably used to position the steering wheel frame 7-1, such as... Figure 5 As shown, the combination is as follows Figure 2 The positioning method shown, in which the molding sub-mold 1-1 is embedded in the heating unit 2, accurately positions the steering wheel relative to the molding sub-mold 1-1. The positioning module can also use methods such as pin positioning, tapered positioning, or magnetic positioning to position parts of the steering wheel frame, such as spokes and center base.

[0021] To facilitate the opening and closing of the heating module, the two heating covers 2-2 are connected and fixed by a connecting plate 2-4, and the two heating bases 2-1 are integrated into one structure. The heating module also includes a pressure boosting module, which in this embodiment is preferably elastic rubber 4. This elastic rubber 4 is installed on the lower part of the connecting plate 2-4 and can abut against the steering wheel when the heating module is closed, applying appropriate downward pressure to the steering wheel frame. Specifically, as shown... Figure 3 As shown, the elastic adhesive 4 presses the steering wheel frame firmly onto the positioning block 3, maintaining the stability of the steering wheel frame 7-1 during the molding process and ensuring that the position and quality of each molded product are highly consistent. Preferably, the pressure boosting module can also be replaced by a pneumatic spring, hydraulic cylinder, or disc spring, as long as it can apply appropriate downward pressure to the steering wheel frame during mold closing.

[0022] Both the heating cover 2-2 and the heating base 2-1 are equipped with heating oil passages 2-5, employing a heat transfer oil circulation heating method. The heating oil passages 2-5 of the two heating covers 2-2 are connected via external oil pipes; the heating oil passages 2-5 of the two heating bases 2-1 form a continuous loop. Specifically, the heating oil passages 2-5 within the heating base 2-1 are designed in a three-dimensional, surrounding manner at the bottom and periphery of the cavity 2-3, working in conjunction with the heating cover 2-2 to achieve full-encirclement heating of the forming sub-mold 1-1, resulting in extremely high heating efficiency. Electric heating rods, electromagnetic induction heating, or steam heating can also be used as alternatives. However, the heat transfer oil circulation heating method provides the best heating efficiency and temperature uniformity for the forming sub-mold 1-1. The heating cover 2-2 also features clearance grooves corresponding to the spokes.

[0023] To further reduce heat loss and improve energy efficiency, the heating module is covered with a heat insulation plate 5. The heat insulation plate 5 is preferably made of a material with low thermal conductivity, such as bakelite. The heat insulation plate 5 not only ensures operational safety and prevents employee burns, but also forms a heat insulation layer around the heating module, reducing heat loss to the surrounding environment and lowering energy consumption.

[0024] The molding sub-mold 1-1 includes an upper mold 1-11 and a lower mold 1-12. The upper mold 1-11 and lower mold 1-12 are designed for quick disassembly, and are preferably connected by bolts after mold assembly. A slot 1-2 is provided at the port of the molding sub-mold 1-1, and a limiting card 1-3 engages within this slot 1-2. For example, the gap between the foam structure at the 3 o'clock and 9 o'clock positions (hand grip area) of the steering wheel and the carbon fiber structure at the 6 o'clock position (lower wheel rim) and 12 o'clock position (upper wheel rim) is relatively small. Specifically, the upper mold 1-11 has an upper slot 1-2, and the lower mold 1-12 has a lower slot 1-2; the limiting card 1-3 includes an upper card and a lower card, which are inserted into the upper slot 1-2 and the lower slot 1-2, respectively. Preferably, both the upper and lower cards are fixedly connected to the upper mold 1-11 and the lower mold 1-12 respectively by locking blocks 1-4. One end of the upper slot 1-2 is provided with a groove 1-5, and the locking block 1-4 is placed in the groove 1-5 and connected to the upper mold 1-11 by bolts; one end of the lower slot 1-2 is provided with a groove 1-5, and the locking block 1-4 is placed in the groove 1-5 and connected to the lower mold 1-12 by bolts; at this time, the locking block 1-4 clamps the upper and lower cards together. The fixing hole on the limiting card 1-3 is adapted to the cross-sectional shape of the steering wheel frame (workpiece) to fix the steering wheel frame.

[0025] The heating module is equipped with a handle 6, which is connected by a screw-in screw. This allows for easy manual pulling out or pushing back of the heating base 2-1. Preferably, a snap-on quick-release handle 6, a magnetic handle 6, or a sliding rail handle 6 can also be used, as long as it allows for quick pulling out of the heating base 2-1 by a single person. To facilitate quick replacement of the molding sub-mold 1-1, multiple sets of screw holes can be pre-set on the molding sub-mold 1-1. With the detachable handle screwed into the screw holes, quick replacement by a single person is possible, suitable for small and micro-sized enterprises with low production volumes. Alternatively, with the magnetic handle, quick replacement can be achieved via a robotic arm, suitable for medium and large enterprises with high production volumes. This reduces the difficulty of operation and the reliance on large auxiliary equipment such as forklifts.

[0026] The workflow is as follows: Step 1: In the pre-molding area (cleanroom), the first molding module is covered with yarn and molded, and then transferred to the molding area; while the yarn is being covered and pre-molded, the mold temperature controller is turned on to preheat the master mold; after the temperature reaches the preset temperature, the heating cover is ready to be opened. Step 2: Place the first molding module into the heating base and start the press to press the mold; Step 3: Once the predetermined curing time is reached, open the heating module, remove the first molding module and place the next molding module in; after the first molding module cools down, open the mold and remove the workpiece, and the first molding module is transferred to the pre-forming area.

[0027] In this invention: I. Quick-change split sub-mold design: The mold system is divided into two parts: a "common heating module" and an "interchangeable molding module." The heating module, as a high-value, universal component, maintains a high temperature for extended periods. Due to the wide variety of steering wheel structures on the market, the molding sub-mold 1-1, as a low-value consumable, can be quickly replaced. This design offers the following technical advantages: ① Molding module replacement eliminates the need to wait for cooling, reducing switchover time from 20-30 minutes in traditional processes to 5-10 minutes; ② One heating module can be used with multiple molding modules, significantly reducing mold development costs; ③ The heating module maintains a constant operating temperature, greatly improving energy efficiency.

[0028] II. Insulation Plate and Targeted High-Efficiency Heating Design: The insulation plate reduces heat loss and improves heating efficiency; the heating base 2-1 has a U-shaped cross-section, supplemented by the heating cover 2-2, achieving full-enclosed heating of the molding sub-mold 1-1, resulting in extremely high heating efficiency. Targeted clearance design protects heat-sensitive components (such as the foam layer at the three and nine o'clock positions). This design solves the common heat-affected zone problem in autoclave processes, preventing product scrap due to overheating.

[0029] III. Rapid and Precise Positioning System with Positioning Block and Cavity Engagement: The precise engagement of positioning block 3 and molding sub-mold 1-1 within the cavity 2-3 ensures accurate positioning after each replacement of molding sub-mold 1-1. This positioning system features: ① Molding sub-mold 1-1 employs a quick-plug design for easy operation; ② High repeatability (±0.05mm), guaranteeing consistent product quality; ③ Positioning block 3 can be quickly replaced to adapt to different product models; ④ Simple, reliable structure and low cost.

[0030] IV. Detachable Handle and Lightweight Sub-mold: The lightweight design and detachable handle of the molding sub-mold 1-1 enable quick single-person replacement. This reduces operational difficulty, decreases reliance on large auxiliary equipment such as forklifts, and improves the flexibility of production scheduling.

[0031] The above descriptions are merely embodiments of the present invention, and common knowledge regarding specific structures and characteristics in the solutions is not described in detail here. It should be noted that those skilled in the art can make various modifications and improvements without departing from the structure of the present invention, and these should also be considered within the scope of protection of the present invention. These modifications and improvements will not affect the effectiveness of the implementation of the present invention or the practicality of the patent.

Claims

1. A quick-change mold system for molding carbon fiber steering wheels, characterized in that: Includes heating module and molding module, The molding module includes multiple molding sub-molds, the number of which is the same as the number of parts of the steering wheel to be molded. Each molding sub-mold only covers the parts of the steering wheel to be molded, and the rest of the steering wheel extends out from the port of the molding sub-mold. The port of the molding sub-mold is provided with a limiting card for fixing the steering wheel frame. The heating module includes multiple heating sections spaced apart; each heating section has a cavity into which a molding sub-mold can be embedded; each heating section includes a heating base and a heating cover. The heating module also includes a positioning module, which is used to fix the steering wheel.

2. The quick-change mold system for molding carbon fiber steering wheels according to claim 1, characterized in that: It also includes a heat insulation plate that covers the outside of the heating module.

3. The quick-change mold system for molding carbon fiber steering wheels according to claim 1, characterized in that: The cavity is located on the heating base, and the side wall of the cavity is provided with an inclination angle; the outer wall of the molding sub-mold is provided with an inclination angle that matches the cavity.

4. The quick-change mold system for molding carbon fiber steering wheels according to claim 3, characterized in that: Both the heating cover and the heating base are equipped with heating oil circuits; the heating oil circuits of the multiple heating covers are connected by external oil pipes; the heating oil circuits of the multiple heating bases are interconnected loops.

5. The quick-change mold system for molding carbon fiber steering wheels according to claim 1, characterized in that: The heating cover is connected and fixed by a connecting plate; the heating module is also equipped with a pressurization module, one end of which is fixedly connected to the connecting plate, and the other end can abut against the steering wheel.

6. The quick-change mold system for molding carbon fiber steering wheels according to claim 1, characterized in that: The molded sub-mold has a slot at its port, and the limiting card is engaged in the slot.

7. The quick-change mold system for molding carbon fiber steering wheels according to claim 1, characterized in that: It also includes a handle, which is mounted on the heating module.

8. The quick-change mold system for molding carbon fiber steering wheels according to claim 1, characterized in that: The heating cover is also provided with relief grooves corresponding to the spokes.

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