Hybrid cockpit cross member and method for producing the same

Abstract

Hybrid cockpit cross member with: a metal tube (10); and a reinforcing material (20) inserted into the metal tube (10), wherein a rib (30) is provided inside the reinforcing material (20) to increase an ability to withstand injection pressure when the metal pipe (10) is overmolded and to ensure strength, characterized in that the reinforcing material (20) consists of at least one material selected from a synthetic resin and a composite material.

Description

Background of the invention 1. Field of the invention

[0001] The present invention relates to a hybrid cockpit cross member, and more particularly to a hybrid cockpit cross member having a structure having enhanced strength and a method having a simplified process for manufacturing the same. 2. Discussion of the state of the art

[0002] A cockpit cross member is a component of a vehicle cockpit module and serves to guide and support a variety of different cockpit components, such as a steering shaft, an instrument panel, an air conditioning system, an airbag, an audio system, etc. Furthermore, the cockpit cross member is a frame designed to prevent lateral bending or warping of a vehicle and increase the durability of a vehicle body. Furthermore, the cockpit cross member forms a guide surface on which the cockpit components are mounted and provides safe protection for the occupants in the event of a frontal collision.

[0003] A cockpit cross member is manufactured using a tube made of a metal such as aluminum, magnesium, or steel, or by injection molding a synthetic resin or composite material. In recent years, a cockpit cross member has been manufactured from a hybrid material that incorporates a composite material or a hybrid substance to reduce cost and weight.

[0004] Fig. Figure 1 shows an example of a hybrid cockpit cross member. A manufacturing process for the illustrated hybrid cockpit cross member is as follows: An aluminum tube is bent into a desired shape and inserted into a mold. Before a synthetic resin is injected onto the tube, the interior of the tube is expanded by applying hydraulic pressure (a process known as hydroforming). The applied hydraulic pressure is between approximately 600 and 900 bar. In this case, the exterior of the tube is insert-molded. The injection pressure is approximately 1300 bar.

[0005] In the manufacturing process described above, one reason for applying hydraulic pressure to the inside of the aluminum tube is to prevent dimensional change and injection leakage due to deformation of the aluminum tube caused by injection pressure during insert molding. Fig. 2 shows an example of a spray leak (left). Fig. 2 also shows an unevenness of pressure in respective areas of the pipe.

[0006] As described above, conventionally, due to the hydroforming process, the number of processes for manufacturing a cockpit cross member is increased, and it is necessary to construct molding devices capable of performing hydroforming, thereby causing excessive costs. On the other hand, excessive deformation occurs in a tube when hydraulic pressure is not applied. US 2015 / 0056428 A1 discloses a hybrid cockpit cross member having the features of the preamble of claim 1. DE 600 18 612 T2 discloses a hydroformed tube that is reinforced. US 5,755,486 A discloses another reinforced component. DE 10 2008 050 313 A1 discloses another cockpit cross member. Overview of the invention

[0007] The present invention relates to providing a cockpit cross member manufactured by an improved method in which insert molding is performed without applying hydraulic pressure to the interior of a metal tube during injection molding, so as to simplify a process for manufacturing a hybrid cockpit cross member and ensure the strength of the cockpit cross member, thereby solving the above-mentioned problems.

[0008] The invention is defined by the features of claim 1. According to the present invention, a hybrid cockpit cross member is provided in which a reinforcement material is inserted into a metal tube, which is a material of a cockpit cross member. The metal tube can be made of a material such as aluminum, magnesium, or steel, like a conventional cockpit cross member. The reinforcement material consists of at least one material selected from synthetic resin or a composite material (e.g., PP+GF50%) and can be produced, for example, by extrusion.

[0009] A rib is formed in the reinforcing material to increase the ability to withstand injection pressure when the metal pipe is insert-molded and to increase strength. The rib can be manufactured in numerous different shapes, such as cross-shaped, linear, polygonal, such as triangular or square, irregular, etc.

[0010] According to another aspect of the present invention, there is provided a method for manufacturing a hybrid cockpit cross member, the method comprising the steps of: providing a metal tube, providing a reinforcing material, inserting the reinforcing material into the provided metal tube to produce a semi-finished cockpit cross member, inserting the semi-finished cockpit cross member into a mold, and performing insert overmolding on the outside of the metal tube in the mold.

[0011] The reinforcement material can be manufactured by injection molding, extrusion casting, or cutting according to the internal shape of the pipe. Furthermore, the reinforcement material inserted into the metal pipe can be fixed using adhesive or other connecting parts.

[0012] The above-described configurations and operations of the present invention will become more apparent from embodiments described below with reference to the accompanying drawings. Brief description of the drawings

[0013] The above and other objects, features and advantages of the present invention will become more apparent to those skilled in the art from the detailed description of exemplary embodiments thereof with reference to the accompanying drawings, in which: Fig. 1 shows an exemplary view of a hybrid cockpit cross member; Fig. 2 shows views describing problems of a conventional hybrid cockpit cross member; Fig. 3 is an exploded view of a hybrid cockpit cross member according to the present invention; Fig. 4 is a cross-sectional view of a reinforcing material (20); Fig. 5 is a view showing an outer side of a semi-finished cockpit cross member in which the reinforcing material (20) is inserted into a metal tube (10); and Fig. 6 is an exemplary view of a hybrid cockpit cross member product manufactured and finally assembled in accordance with the present invention. Detailed description of exemplary embodiments

[0014] Exemplary embodiments of the present invention are described in more detail below with reference to the accompanying drawings.

[0015] Fig. 3 is an exploded view of a hybrid cockpit cross member according to the present invention.

[0016] A tubular or rod-shaped reinforcement material 20 is inserted into a metal tube 10. The metal tube 10 is made of a material such as aluminum, magnesium, or steel. The reinforcement material 20 is manufactured by extruding a synthetic resin or a composite material (e.g., PP+GF50%).

[0017] As described above, when the metal pipe 10 is manufactured with a multi-layer structure in which the reinforcing material 20 is inserted into the metal pipe 10, the thickness or diameter can be reduced compared with a metal pipe having the same specification as the metal pipe 10, thereby achieving the additional effects of cost reduction, weight reduction, and increased design flexibility.

[0018] Fig. 4 is a cross-sectional view of a reinforcing material 20.

[0019] By using a cross-shaped (“+”) rib 30 in an extruded tube, the ability to withstand injection pressure can be increased when the metal tube 10 is overmolded, and strength against vehicle collision and strength against sagging can be ensured when the cockpit cross member is used in an actual vehicle after manufacture.

[0020] The Fig. The rib 30 shown in Figure 4 is cross-shaped ("+"), but is not limited thereto. To achieve the goal of increasing the strength of the reinforcing material 20, the rib 30 can be formed in a variety of shapes, such as a simple linear ("-") shape, a polygonal shape such as a triangle or a square, an irregular shape (star or oval), or the like.

[0021] Fig. 5 shows a semi-finished cockpit cross member in a state where the reinforcement material 20 is inserted into the metal tube 10. Here, the term "semi-finished cockpit cross member" refers to a product before insert molding by placing the semi-finished cockpit cross member in a mold for insert molding. After placing the semi-finished cockpit cross member in the mold, insert molding with a synthetic resin is performed directly, without performing the hydroforming process using hydraulic pressure required in a conventional process.

[0022] Fig. Figure 6 is an exemplary view of a hybrid cockpit cross member product manufactured and finally assembled according to the present invention. Numerous different required brackets and supports are attached to an insert-molded cross member.

[0023] According to the present invention, the strength (A) against noise, vibration, harshness (NVH), the strength (B) against collision, and the strength (C) against sagging are all improved. However, to improve the strength, the cost is not increased and the process is not complicated; rather, the hydroforming process is eliminated. Thus, the cost is reduced and the process is simplified.

[0024] The following describes in detail a process for manufacturing the hybrid cockpit cross member by insert injection molding.

[0025] First, a metal tube 10 is provided. A material such as aluminum, magnesium, or steel can be used as the metal material.

[0026] A reinforcement material 20 is provided. The reinforcement material 20 may be made of a synthetic resin or a composite material (e.g., PP+GF50%) with high strength. The reinforcement material 20 may be manufactured by injection molding, extrusion molding, or cutting according to its internal shape.

[0027] The reinforcement material 20 is inserted into the provided metal tube 10. Cold or hot insertion is possible, and the dimensions of the metal tube 10 and the reinforcement material 20, and a gap between them, are determined according to the insertion method performed. Whether an adhesive or connecting parts (e.g., screws or the like) are used between the metal tube 10 and the reinforcement material 20 is further determined according to the design specifications of one skilled in the art.

[0028] A semi-finished cockpit cross member manufactured as described above is placed in a mold.

[0029] The outside of a tube in the mold is insert-molded. In this case, hydroforming to expand the inside of the tube using hydraulic pressure is not necessary. Therefore, the injection pressure is reduced from approximately 1300 bar, which is conventionally used, to a pressure of less than approximately 1000 bar, or to a pressure of several hundred bars, which is less than or equal to 1000 bar.

[0030] After performing a pressure holding process or the like, the mold is opened (mold opening) to remove a molded product, and necessary components such as a steering column, a bracket, and a stay are attached to the molded product. A final inspection is performed using a jig, such as a reject jig, to release a finished hybrid cockpit cross member.

[0031] According to the present invention, since a hydroforming process required for a conventional hybrid cockpit cross member is not provided, the number of manufacturing processes is reduced and hydroforming devices are not required, thereby increasing the strength of a cockpit cross member and improving NVH strength, collision strength, and sag strength.

Claims

[1] Hybrid cockpit cross member with: a metal tube (10); and a reinforcing material (20) inserted into the metal tube (10), wherein a rib (30) is provided inside the reinforcing material (20) to increase an ability to withstand injection pressure when the metal pipe (10) is overmolded and to ensure strength, characterized by , that the reinforcing material (20) consists of at least one material selected from a synthetic resin and a composite material. [2] Hybrid cockpit cross member according to claim 1, wherein the composite material is PP+GF50%. [3] Hybrid cockpit cross member according to claim 1, wherein the rib (30) is cross-shaped. [4] A method for producing a hybrid cockpit cross member according to any one of claims 1 to 3, the method comprising the following steps: Providing a metal tube (10) and a reinforcing material (20) to be inserted into the metal tube (10); Inserting the reinforcement material (20) into the provided metal tube (10) to produce a semi-finished cockpit cross member; Inserting the semi-finished cockpit cross member into a mold; and Performing insert molding on the outside of the metal tube (10) in the mold. [5] The method according to claim 4, wherein in providing the reinforcing material (20), the reinforcing material (20) is produced by one of the following methods: an injection molding method, a continuous casting method and a cutting machining method. [6] The method according to claim 4, wherein inserting the reinforcing material (20) into the provided metal pipe (10) comprises fixing the reinforcing material (20) inserted into the metal pipe (10) by means of a connecting part.

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