JP2012254663A - Instrument panel reinforcement material structure for automobile made of aluminum alloy - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an instrument panel reinforcement material structure for an automobile formed of an aluminum alloy which can satisfy a structural requirement which is different at a driver's seat side and at a front passenger seat side, and unique to the instrument panel reinforcement material structure for the automobile by a configuration manufacturable at a low cost.SOLUTION: The instrument panel reinforcement material structure formed of the aluminum alloy is provided with a main member 10 which is extended in the width direction of a vehicle body and whose both axial ends are attached to a vehicle body frame directly or via a bracket. The main member 10 has a driver's seat side hollow cross section 11 formed of a hollow extruded shape material formed of an aluminum alloy and constituting the driver's seat side, and a front passenger seat side open cross section 12 formed to be integrally continuous to the driver's seat side hollow cross section 11 by cutting off a part of the hollow extruded shape material formed of the aluminum alloy, and constituting the front passenger seat side.

Description

  The present invention relates to an instrument panel reinforcement structure for automobiles made of aluminum alloy.

  In a vehicle body such as an automobile, an instrument panel reinforcing material structure for supporting a steering column is provided in the vehicle body width direction in front of the vehicle interior. As is well known, this instrument panel reinforcing member structure includes a main member (also referred to as an instrument panel reinforcement, a steering support beam, a steering humber beam, a cross car beam, etc.) that is an instrument panel reinforcing member main body, and a connecting stay.

  The main member extending in the vehicle body width direction is attached to the side frame of the vehicle body, either directly or via a bracket, at both ends in the axial direction, and is installed near the center of the vehicle body to move downward or forward of the vehicle body. It is connected to a vehicle body floor or a dash panel (cowl) by a connecting stay extending to the front. For such a main member, various cross-sectional shapes are selected. Further, in order to avoid interference with other parts (other members), bending, swaging, or the like may be performed in the longitudinal direction (axial direction). Furthermore, various materials, such as a steel plate, aluminum, and magnesium, are selected from the viewpoint of cost and performance.

  The main member is required to have high rigidity in order to prevent steering vibration during traveling. High strength is also required for the load from the front of the vehicle through the steering in the frontal collision to the rear of the vehicle, the load from the front of the vehicle due to the occupant's forward movement, and the axial load of the main member in a side collision. Is done. In recent years, from the viewpoint of reducing the weight of automobiles, it has been desired to further reduce the weight while securing these strengths and rigidity.

  Since the aluminum alloy material is lighter than conventionally used steel plates, application to frame parts (frame parts) such as main members is also expected. Up to now, aluminum alloy main members made of aluminum alloy sheets, aluminum alloy casts, or aluminum alloy extruded shapes formed by press molding or roll molding have been studied or put into practical use. However, since the main member made of an aluminum alloy has a higher material cost than that made of a steel plate, it is a problem to suppress processing or joining cost as much as possible.

  In a frame component (frame member) such as a main member, it is desirable to adopt a structure having a hollow closed cross-section in order to reduce the weight while satisfying the requirements of rigidity and strength. For this reason, when manufacturing an aluminum alloy main member using an aluminum alloy plate material, members are often joined after pressing or roll processing to form a cross-sectional structure having a hollow closed cross-section. However, the main member having such a structure has a problem that the welding cost is high because the weld line length is long.

  Further, in the case of manufacturing an aluminum alloy main member by casting, there is an advantage that it is difficult to form a hollow closed cross-section portion, although there is an advantage that an attachment portion with other parts can be integrally formed. . For this reason, it is common to adopt a U-shaped cross-sectional shape and to provide reinforcing ribs to ensure strength and rigidity, but such a main member is compared with the one having the hollow closed cross section. There is a problem that the weight is heavy.

  On the other hand, according to the extruded shape of aluminum alloy, there is a great advantage that a linear member having a hollow closed cross section can be formed in advance without welding. Since the main member is desired to be provided linearly over substantially the entire length in the vehicle width direction in order to reduce weight and load in the vehicle width direction, it can be said that the main member is a part (member) to which the aluminum alloy extruded shape is easily applied. Thus, as represented by Patent Document 1 and the like, several main members (steering support beams in Patent Document 1) using an aluminum alloy extruded profile having the same cross section in the longitudinal direction have been proposed.

  However, in a main member using an aluminum alloy extruded shape, the shape restriction is often a problem because the aluminum alloy extruded shape has a substantially uniform cross section in the longitudinal direction (axial direction). For this reason, a main member having a structure in which a variable cross section is provided, for example, by pressing a part of an aluminum alloy extruded shape has been proposed (Patent Document 2). In addition, as a method of changing the cross-sectional shape in the longitudinal direction in a complicated manner, hydraulic forming or the like has been proposed. However, these proposals often have a problem of cost increase due to long processing time.

  Further, in the passenger seat side portion (passenger seat side region) of the main member, the required values of rigidity and strength are relatively low compared to the driver seat side portion (driver seat side region) to which the steering column is connected. On the other hand, there is a relationship such as the arrangement of the storage box, and the shape restriction is stricter, and a small-diameter thin wall tube is desired as compared with the driver side portion. For this reason, in the conventional steel pipe main member, the passenger seat side portion is generally reduced in diameter and thickness by swaging. However, when using an aluminum alloy material that is inferior in formability compared to a steel plate, it is very difficult to obtain a similar shape by swaging or the like.

  Therefore, a machine using a plurality of members having different cross sections for the driver's seat side portion and the passenger's seat side portion, welding them together, or caulking joints using plastic deformation such as contraction pipes, or using bolts, pins, etc. Many main members made of aluminum alloy have been proposed (Patent Documents 3 to 6). However, these main members often have a problem of cost increase due to an increase in the number of parts. In addition, in the case of using melt welding at the time of manufacture, there is a problem that the joining cost itself is higher in the aluminum alloy material than in the case of using a steel plate. Furthermore, since the coefficient of thermal expansion is high, it is necessary to solve production problems such as suppression of thermal deformation during welding, and it takes time to start up the product.

  To summarize the above, in the main member (instrument panel reinforcement body), the driver's seat side part to which the steering column is joined has a strong demand for high strength and high rigidity, and a high-strength material large-diameter section frame is required. The passenger seat side portion satisfies the shape constraints and requires a small-diameter thin frame in order to reduce the weight, and it can be said that a structure (configuration) capable of manufacturing these at low cost is required. In particular, in an aluminum alloy material having a higher joining cost than steel, a structure that shortens the joining length as much as possible is necessary to reduce the cost.

JP 2003-34266 A JP 2010-52487 A Japanese Patent No. 3734651 JP 2004-189040 A Japanese Patent No. 4496592 Japanese Patent No. 4487366

  Therefore, the subject of the present invention is to be able to meet the structural requirements peculiar to the instrument panel reinforcing material structure for automobiles that the driver seat side portion and the passenger seat side portion are different from each other by a configuration that can be manufactured at a low cost. Another object of the present invention is to provide an instrument panel reinforcement structure for automobiles made of aluminum alloy.

  In order to solve the above problems, the present invention takes the following technical means.

  According to a first aspect of the present invention, there is provided an automotive instrument panel reinforcing material structure made of an aluminum alloy, comprising: a main member that extends in a vehicle body width direction and that has both axial ends attached to a vehicle body frame directly or via brackets. Is formed of an aluminum alloy hollow extruded section and forms a driver seat side portion, a driver seat side hollow cross section, and a part of the aluminum alloy hollow extruded section is cut away to form the driver seat side hollow cross section. An instrument panel reinforcing material structure for an automobile made of an aluminum alloy, characterized in that it has a passenger-seat-side open cross-section portion that is formed integrally with the passenger-seat side portion.

  According to a second aspect of the present invention, in the instrument panel reinforcing material structure for an automobile made of aluminum alloy according to the first aspect, one end is joined to a stepped portion between the driver-side hollow cross-section and the passenger-side open cross-section. The other end is provided with a connecting stay made of aluminum alloy connected to the vehicle body floor.

  According to a third aspect of the present invention, in the instrument panel reinforcing material structure for an automobile made of aluminum alloy according to the second aspect, the one end of the connecting stay has the driver side hollow cross section and the passenger side open cross section. In the step part with the part, it is joined so as to close the hollow opening part of the step part.

  According to a fourth aspect of the present invention, in the instrument panel reinforcing material structure for an automobile made of aluminum alloy according to any one of the first to third aspects, the main member has an opening section on the passenger seat side in a vehicle body height direction. It is attached to the said vehicle body frame so that it may become an upward convex attitude | position.

  According to a fifth aspect of the present invention, in the instrument panel reinforcing material structure for an automobile made of aluminum alloy according to any one of the first to fourth aspects, the cross-sectional shape of the main member is a point-symmetric cross-sectional shape centered on the axis. It is characterized by being.

  According to a sixth aspect of the present invention, in the instrument panel reinforcing material structure for an automobile made of aluminum alloy according to any one of the first to fifth aspects, a cross-sectional shape of the driver side hollow cross-section of the main member is substantially circular. The cross-sectional shape of the passenger seat side open cross-section is substantially semicircular.

  The invention of claim 7 is an aluminum instrument panel reinforcement structure for an automobile according to any one of claims 1 to 6, wherein the aluminum alloy hollow extruded shape has an outer periphery centered on an axis. Groove-shaped concave portions are formed in two equal parts at a predetermined length in the axial direction, and both end portions of the peripheral wall extending in the axial direction of the open section on the passenger seat side of the main member are the two concave portions. Is formed by press shearing along the axial direction of a predetermined length.

  According to an eighth aspect of the present invention, in the instrument panel reinforcing material structure for an automobile made of aluminum alloy according to any one of the first to seventh aspects, the front cross section of the front side of the main member has an axial direction. Folded portions directed toward the axial center are formed at both ends of the extending peripheral wall.

  The invention of claim 9 is the instrument panel reinforcing material structure made of aluminum alloy according to any one of claims 1 to 8, wherein the aluminum alloy material used is 5000 series aluminum alloy material, 6000 series aluminum alloy material or It is a 7000 series aluminum alloy material.

  The instrument panel reinforcing material structure for automobiles made of aluminum alloy according to claim 1 (hereinafter also referred to simply as “aluminum alloy instrument panel reinforcing material structure”) has a driver-seat-side hollow cross-sectional portion having a hollow cross-sectional shape. Since it is configured, high deformation strength, rigidity, and vibration characteristics required for the driver side portion of the main member can be ensured. In addition, the passenger seat side part, which has lower requirements for rigidity and deformation strength than the driver side part and has severe shape constraints, has an open cross-sectional part whose cross section is smaller in diameter than the driver side part. Therefore, it is possible to satisfy the small diameter (small space) and light weight required for the passenger seat side portion of the main member. In addition, the aluminum alloy instrument panel reinforcing member structure has a main-member-side hollow section of the driver's seat formed by a predetermined axial length portion of the aluminum alloy hollow extruded section, and is integrated with the driver-side hollow section. Since the open cross section on the passenger seat side that is connected to is formed by cutting a part of the aluminum alloy hollow extruded section, the number of components can be reduced, and the main member can be manufactured without welding. The cost can be reduced and the shape accuracy can be improved. Therefore, according to the instrument panel reinforcing material structure made of aluminum alloy according to claim 1, the structural requirement unique to the instrument panel reinforcing material structure for automobiles that the driver seat side portion and the passenger seat side portion are different due to the structure that can be manufactured at low cost. Can be met.

  According to the instrument panel reinforcing member structure made of aluminum alloy according to claim 2, one end is joined to a step (boundary portion) between the driver side hollow cross section and the passenger side open cross section, and the other end. Has a connecting stay made of aluminum alloy that is connected to the vehicle body floor, and by transmitting the load to the vehicle body floor side by the stay, the rigidity is lower than that on the driver's seat side due to the open cross-sectional structure. Load transmission to the passenger side can be suppressed. Further, since the main member is a member (integrated member) integrally including the driver side hollow cross section and the passenger side open cross section, the connecting stay can be easily positioned at the stepped portion. There is an advantage that the weld length in the weld joint can be shortened (half the cross-sectional circumference).

  According to the instrument panel reinforcing member structure made of aluminum alloy according to claim 3, one end is joined to the stepped portion between the driver side hollow cross section of the main member and the passenger seat side open cross section, and the other end is The connecting stay made of an aluminum alloy connected to the vehicle body floor has an opening in the step portion (hollow opening portion) at the step portion between the driver seat side hollow cross section and the passenger seat side open cross section. Therefore, the deformation of the driver side hollow cross-section can be more efficiently suppressed. In addition, since the load is transmitted to the vehicle body floor side while suppressing the load transmission to the passenger seat side open section, the deformation strength and rigidity of the main member can be increased.

  According to the instrument panel reinforcing member structure made of aluminum alloy according to claim 4, the main member is required to have a high deformation strength against the collision load in the longitudinal direction of the vehicle body. Since the seat-side open cross-section portion is configured to have an upwardly convex posture in the vehicle body height direction (a posture that opens downward in the vehicle body height direction), the passenger-side open cross-section portion is Compared to a rearwardly convex posture (a posture in which the rear side or front side of the vehicle body is open), the cross-sectional secondary moment with respect to the bending load of the main member increases, and the main member accordingly The strength and rigidity of 10 can also be increased. Further, the rigidity of the main member against the load transmitted through the steering column can be increased. Further, in the case of the structure connected to the vehicle body floor via the connection stay as in claims 2 and 3, the connection stay is resistant to deformation in the vertical direction of the vehicle body, so that the rigidity against the bending load in the vertical direction of the vehicle body is obtained. The decrease can also be suppressed.

  Moreover, according to the instrument panel reinforcing member structure made of aluminum alloy according to claim 5, the cross-sectional shape of the main member (the cross-sectional shape of the aluminum alloy hollow extruded shape forming the main member) is a point-symmetric cross-sectional shape centering on the axis. As a result, two parts can be obtained by cutting the open cross-sectional shape of the passenger seat side portion, and the cost can be reduced by reducing the yield. The cross-sectional shape of the main member is conveniently selected according to the shape constraints, the required performance for the parts, and the necessity of forming a joint surface with other parts.

  Further, according to the instrument panel reinforcing member structure made of aluminum alloy according to claim 6, the cross-sectional shape of the driver side hollow cross-section of the main member is made substantially circular, and the cross-sectional shape of the passenger side open cross-section is made substantially corresponding to this. By adopting a semi-circular shape and thus a circular cross-sectional shape with little anisotropy as a cross-sectional shape, the instrument panel reinforcement is provided with high rigidity against deformation in any direction in the driver's seat side portion. Good vibration characteristics can be secured for the natural frequency, which is one of the required performances in the material structure. The cross-sectional shape does not have to be completely circular, and may be a substantially circular cross-sectional shape in which a flat seat surface or the like for joining to other parts is formed in advance.

  According to the aluminum alloy instrument panel reinforcing material structure of claim 7, the aluminum alloy hollow extruded shape forming the main member has groove-shaped recesses at two locations that divide the outer periphery of the shaft center into two equal parts. Since it is formed over a predetermined length in the axial direction, the two recesses are press-sheared along the predetermined length axial direction and cut into a slit shape, and this press-sheared portion is integrated with the driver side hollow cross-section. By cutting the aluminum alloy hollow extruded section so as to be both ends of the peripheral wall extending in the axial direction of the passenger seat side open cross-section connected to the driver seat side hollow cross section and the passenger seat side open cross section The main member can be easily manufactured without performing welding joining. In addition, since both end portions of the peripheral wall of the open side section of the passenger seat are formed by press-shearing the concave portion, it is difficult for an operator to touch both end portions of the peripheral wall that become the concave portion when the main member is attached, etc. It is possible to prevent a cut by contact. Further, since the concave portion acts as a reinforcing rib, it is possible to increase the load resistance against the axial load in the main member and to make it difficult to cause a cross-sectional deformation against the bending load.

  Further, according to the instrument panel reinforcing member structure made of aluminum alloy according to claim 8, the passenger member side open cross section of the main member is formed with a folded portion toward the axial center at both end portions of the circumferential wall extending in the axial direction. It is difficult for an operator to touch the tip of the folded portion at the time of attaching the main member, and it is possible to prevent a cut from being caused by the contact.

  According to the instrument panel reinforcing member structure made of aluminum alloy according to claim 9, the aluminum alloy material used is a 5000 series aluminum alloy material, a 6000 series aluminum alloy material, or a 7000 series aluminum alloy material, and the aluminum alloy material suitable as a material is used. An instrument panel reinforcement structure made of aluminum alloy can be used.

1 is a perspective view schematically showing an instrument panel reinforcement structure made of an aluminum alloy according to an embodiment of the present invention. It is a perspective view which shows roughly the structure of the main member in FIG. FIG. 2 is a perspective view schematically showing a structure of a connecting stay for a vehicle body floor in FIG. 1. It is a perspective view which shows schematically the instrument panel reinforcement structure made from aluminum alloy by another embodiment of this invention. It is sectional drawing which shows the cross section of the aluminum alloy cylindrical tubular extrusion shape with a recessed part which is an example of the aluminum alloy hollow extrusion shape material which forms the main member which concerns on the aluminum alloy instrument panel reinforcement material structure of this invention. It is a perspective view which shows roughly the principal part of the main member formed with the aluminum alloy circular tubular extruded shape with a recessed part shown in FIG. FIG. 7 is an explanatory view schematically showing an example of a method of manufacturing a main member according to an instrument panel reinforcing material structure made of an aluminum alloy of the present invention, in which (a) shows a press shearing process, and (b) Is a diagram showing a saw cutting step, (c) is a diagram showing the two parts (main member) obtained. It is the sectional view on the AA line in (a) of FIG. It is explanatory drawing which shows schematically another example of the method of manufacturing the main member which concerns on the instrument panel reinforcement material structure made from aluminum alloy of this invention, Comprising: (a) is a figure which shows a press shear process, The (b) is The figure which shows a saw cutting process, (c) is a figure which shows two parts obtained by the saw cutting process, The (d) is two parts (main member) in which the folding | turning part by the folding process was formed. FIG. It is the BB sectional view taken on the line of (a) of FIG. It is sectional drawing which shows the folding | returning part formed in the peripheral wall edge part of the passenger seat side open cross-section part of a main member.

  Embodiments of the present invention will be described below with reference to the drawings. 1 is a perspective view schematically showing an instrument panel reinforcing member structure made of aluminum alloy according to an embodiment of the present invention, FIG. 2 is a perspective view schematically showing a structure of a main member in FIG. 1, and FIG. 3 is a vehicle body in FIG. It is a perspective view which shows roughly the structure of the connection stay for floors.

  As shown in FIG. 1, an aluminum alloy instrument panel reinforcing material structure 1 according to this embodiment has a main member 10 extending in the vehicle body width direction and one end portion welded to the main member 10 to show the main member 10. The connecting stay 20 for connecting to the vehicle body floor not to be connected is connected to the cowl for connecting the main member 10 to a cowl (COWL) on the front side of the vehicle body (not shown). And a stay 30.

  The main member 10 is formed of an aluminum alloy hollow extruded section, and the driver seat side hollow cross-section 11 constituting the driver seat side portion and a part of the aluminum alloy hollow extruded section are cut off to perform the operation. It is formed integrally with the seat-side hollow cross-section portion 11 and has a passenger-seat-side open cross-section portion 12 that constitutes a passenger seat-side portion (see FIG. 2). In this embodiment, an aluminum alloy tubular extruded shape is used as the aluminum alloy hollow extruded shape, and the driver side hollow cross-sectional portion 11 has a substantially cylindrical shape, and the passenger seat side opening is opened. The cross section 12 has a substantially semi-cylindrical shape. In this embodiment, as an example, the cross-sectional shape of the driver-seat-side hollow cross-sectional portion 11 is substantially circular, and the cross-sectional shape of the passenger-seat-side open cross-sectional portion 12 is substantially semicircular. The cross-sectional shape of 11 is selected for convenience from the viewpoint of shape restrictions, product requirement specifications, and joining with other components, such as a rectangular cross section and a circular cross section with a flat portion.

  A plate-like bracket 40a made of aluminum alloy is welded to the end of the main member 10 on the passenger seat side open cross section (passenger seat side semi-cylindrical portion) 12 side. An annular bracket 40b is formed at the end of the main member 10 on the driver seat side hollow cross section (driver seat side cylindrical portion) 11 side by pipe expansion processing. The bracket 40a is formed with a bolt hole for connecting the main member 10 to a side frame on one side of the vehicle body with a bolt. The bracket 40b is formed with a bolt hole for connecting the main member 10 to the other side frame of the vehicle body with a bolt. Note that the processing method for connecting the end of the main member 10 to the vehicle body may be selected as necessary. The processing method for expanding the end portion may include press expansion or electromagnetic forming. You may apply.

  The connecting stay 20 (see FIG. 3) made of aluminum alloy for connecting the main member 10 to a vehicle body floor (not shown) has an upper end portion (one end portion) 20a at the driver side hollow cross section 11 and the passenger seat side. It is welded and joined to a step part (boundary part) with the open cross-section part 12, and a lower end part (the other end part) 20b is connected to the vehicle body floor by welding joining.

  When the connecting stay 20 is connected to the vehicle body floor, the passenger seat side open cross-section 12 of the main member 10 has an upwardly convex posture in the vehicle body height direction (a posture that opens downward in the vehicle body height direction). The upper end portion 20a is weld-joined to the step portion so as to be positioned with respect to the passenger seat side open cross-section portion 12 so as to be. In this case, the upper end 20a of the connecting stay 20 is welded and joined to the inner peripheral surface of the passenger seat side end of the driver seat side hollow cross section 11 so as to close the substantially circular opening of the end.

  Further, the connecting stay 30 made of aluminum alloy for connecting the main member 10 to the cowl is such that the passenger seat side open section 12 of the main member 10 protrudes upward in the vehicle body height direction when connected to the cowl. Positioned with respect to the passenger seat side open section 12 so as to be in a posture, one end thereof is welded to the passenger seat side open section 12 and the other end is coupled to the cowl. It has become.

  The main member 10 is configured such that the passenger seat side open cross-sectional portion 12 has an upwardly projecting posture in the vehicle body height direction when attached to the vehicle body frame. Although it is preferable to have a vertically upward posture as shown, the main member 10 has an open section 12 with respect to a vertical line extending in the vertical direction so that the connecting stay 20 is easily welded to the main member 10. May be configured to be inclined in a range of about ± 30 ° in the longitudinal direction of the vehicle body.

  And as a material of the member (component) which comprises this instrument panel reinforcement material structure 1 made from an aluminum alloy, it is good that it is a 5000 series, 6000 series, or 7000 series aluminum alloy material. Such an aluminum alloy material can ensure the strength and rigidity necessary for the instrument panel reinforcement structure for automobiles as a material. In consideration of the requirement for high strength in an indoor space that is not a corrosive environment, the main member 10 formed of an extruded profile is made of a plate material bracket such as a 7000 series aluminum alloy material and connection stays 20 and 30. It is optimal to apply a 5000 series aluminum alloy material that can easily ensure the strength of the welded portion.

  Note that the method of welding joining between the main member 10 and the connecting stays 20 and 30 or the bracket 40a may be conveniently selected as required, such as MIG welding or laser welding.

  Thus, in the instrument panel reinforcing member structure 1 made of aluminum alloy according to this embodiment, the driver seat side portion is constituted by the driver seat side hollow cross-sectional portion 11, so that the driver seat side portion of the main member 10 is required. High deformation strength, rigidity, and vibration characteristics can be ensured. Further, since the passenger seat side portion, which is less demanded of rigidity and deformation strength than the driver seat side portion and has a strict shape constraint requirement, is constituted by the passenger seat side open section 12, the assistant of the main member 10 It is possible to satisfy the reduction in diameter (reduction in space) and the reduction in weight required for the seat side portion.

  Further, in this aluminum alloy instrument panel reinforcement member structure 1, the driver seat side hollow cross section 11 of the main member 10 is formed by a predetermined axial length portion of the aluminum alloy hollow extruded section, and this driver seat side hollow cross section. Since the passenger seat side open cross-sectional portion 12 integrally connected to the portion 11 is formed by cutting a part of the aluminum alloy hollow extruded shape, unlike the conventional case, the number of components can be reduced. The cost can be reduced and the shape accuracy can be improved because the main member 10 can be manufactured without welding.

  Therefore, according to the instrument panel reinforcing material structure 1 made of aluminum alloy, the structural requirement unique to the instrument panel reinforcing material structure for an automobile, which is different between the driver's seat side portion and the passenger seat side portion, can be satisfied due to the structure that can be manufactured at a low cost. be able to.

  Further, according to the instrument panel reinforcing material structure 1 made of aluminum alloy, one end 20a is joined to a step (boundary portion) between the driver side hollow cross section 11 and the passenger side open cross section 12, and the other end Since the portion 20b includes a connection stay 20 made of aluminum alloy that is connected to the vehicle body floor, the load is transmitted to the vehicle body floor side by the connection stay 20, so that the rigidity is higher than that of the driver seat side due to the open cross-sectional structure. It is possible to suppress the load transmission to the passenger seat side where is low. Further, since the main member 10 is a member (integrated member) integrally including the driver side hollow cross section 11 and the passenger side open cross section 12, the connecting stay 20 is easily positioned at the stepped portion. In addition, there is an advantage that the weld length in the weld joint can be shortened (half the circumferential length of the cross section).

  Further, according to the instrument panel reinforcing material structure 1 made of aluminum alloy, the stepped portion of the connecting stay 20 is formed at one end portion of the stepped portion with the passenger seat side open sectional portion 12 of the driver seat side hollow sectional portion 11. Therefore, the deformation of the driver's seat side cylindrical portion 11 can be more efficiently suppressed. In addition, the deformation strength and rigidity of the main member 10 can be increased by suppressing the load transmission to the passenger seat side open cross section 12 and transmitting the load to the vehicle body floor side.

  Further, according to the instrument panel reinforcing material structure 1 made of aluminum alloy, the main member 10 that requires high deformation strength against the collision load in the longitudinal direction of the vehicle body is an assistant when the main member 10 is attached to the vehicle body frame. Since the seat-side open cross section 12 is configured to have an upwardly convex posture in the vehicle body height direction, the passenger seat-side open cross-section portion 12 is configured to have a convex posture in the front or rear direction of the vehicle body. Compared to the above (see FIG. 4), the secondary moment of inertia with respect to the bending load of the main member 10 is increased, and the strength and rigidity of the main member 10 can be increased accordingly. Further, the rigidity of the main member 10 against the load transmitted through the steering column can be increased.

  FIG. 4 is a perspective view schematically showing an aluminum alloy instrument panel reinforcement structure according to another embodiment of the present invention.

  As shown in FIG. 4, the difference from the aluminum alloy instrument panel reinforcing material structure 1 shown in FIG. 1 is that the main member 10 of the aluminum alloy instrument panel reinforcing material structure 1 ′ has an opening section on the passenger seat side. 12 is configured to have a posture that protrudes forward of the vehicle body. That is, the connecting stay 20 ′ is provided on the passenger seat side so that the passenger seat side open section 12 of the main member 10 is in a posture protruding forward of the vehicle body (posture of opening to the rear of the vehicle body) when connected to the vehicle body floor. Positioned with respect to the semi-cylindrical portion 12, the upper end 20 a ′ is the outer periphery of the end of the driver-seat-side hollow cross-section 11 at the step between the driver-seat-side hollow cross-section 11 and the passenger-seat-side open cross-section 12. It is welded to the part. Further, the coupling stay 30 ′ for the cowl is positioned with respect to the passenger seat side open cross section 12 so that the passenger seat side open cross section 12 has a convex posture toward the front of the vehicle body when coupled to the cowl. One end thereof is welded and joined to the passenger seat side open cross section 12.

  The aluminum alloy instrument panel reinforcing material structure 1 ′ configured in this way also has a structure that can be manufactured at a low cost, similar to that shown in FIG. It can meet the structural requirements unique to instrument panel reinforcement structures.

  FIG. 5 is a cross-sectional view showing a cross section of an aluminum alloy tubular extruded shape with a recess, which is an example of an aluminum alloy tubular extruded shape forming a main member according to the aluminum alloy instrument panel reinforcement structure of the present invention. is there.

  As an aluminum alloy hollow extruded shape forming the main member 10 of the aluminum alloy instrument panel reinforcing material structure of the present invention, an aluminum alloy tubular extruded shape with recesses (hereinafter simply referred to as “circular shaped extruded shape with recesses”). Also referred to as 100). As shown in FIG. 5, groove-shaped recesses 100 a, 100 a are formed over substantially the entire length in the axial direction at two locations obtained by equally dividing the outer periphery centered on the shaft center. Yes. In the following, the manufacturing method will be described by taking as an example a structure in which two groove-shaped recesses are provided at positions that are point-symmetric with respect to the axis of the cross section. When processing is performed, it is preferable because two parts can be obtained, which is advantageous for cost reduction due to yield reduction.

  FIG. 6 is a perspective view schematically showing a main part of the main member formed of the aluminum alloy circular tubular extruded shape with recesses shown in FIG.

  In this way, in the case where the main member 10 is formed by the tubular extruded shape member 100 with the recesses, the two recesses 100a, 100a are press-sheared along the predetermined length axial direction and cut into a slit shape. The cylindrical extruded shape member 100 with the recess is sawed so that the press shear portion becomes the peripheral wall end portions 12a, 12a extending in the axial direction of the passenger seat side open cross section 12 integrally connected to the driver side hollow cross section 11. By cutting, the main member 10 having the driver side hollow cross section 11 and the passenger side open cross section 12 can be easily manufactured without welding.

  In addition to the point symmetry with respect to the axial center, the following effects obtained by providing the recesses 100a and 100a as shown will be described. In the case of this structure, the peripheral wall end portions 12a, 12a of the passenger seat side open cross section are formed by press-shearing the concave portions 100a, 100a. Therefore, it is difficult to touch the peripheral wall end portions 12a and 12a, and it is possible to prevent a cut from being caused by the contact. In addition, since the concave portions 100a and 100a function as reinforcing ribs, it is possible to increase the load resistance with respect to the axial load in the main member 10 and to prevent the cross-sectional deformation with respect to the bending load.

  Next, a method for manufacturing a main member according to the instrument panel reinforcing material structure made of an aluminum alloy of the present invention will be described. FIG. 7 is an explanatory view schematically showing an example of a method of manufacturing a main member according to an instrument panel reinforcing material structure made of an aluminum alloy of the present invention, in which (a) shows a press shearing process, and (b) Is a diagram showing a saw cutting step, (c) is a diagram showing the two parts (main member) obtained. FIG. 8 is a cross-sectional view taken along line AA in FIG.

  In this main member manufacturing method, a cylindrical extruded shape member 100 with a recess is used. First, the press shearing process (trimming process) shown in FIG. 7A will be described. In the central part in the axial direction (longitudinal direction) of the cylindrical extruded shape 100 with recesses, the recesses 100a and 100a have predetermined length axes. Press shear along the direction and cut into slits (see FIG. 8). W1 indicates a press sheared part cut into a slit shape.

  Next, the saw cutting step shown in FIG. 7 (b) will be described. Both ends of the press shearing portion (trim portion) W1 are saw cut along the half circumference of the cylindrical extruded shape member 100 with the recess. . W2 represents a saw cutting part.

  As a result, as shown in FIG. 7 (c), so-called double-cutting can be performed in which two main members 10 having the driver-seat-side hollow cross-section 11 and the passenger-seat-side open cross-section 12 are obtained simultaneously. Product yield can be improved.

  Next, another method for manufacturing the main member according to the instrument panel reinforcing member structure made of an aluminum alloy of the present invention will be described. FIG. 9 is an explanatory view schematically showing another example of a method of manufacturing a main member according to an instrument panel reinforcing material structure made of an aluminum alloy of the present invention, in which (a) shows a press shearing process, (b) is a diagram showing a saw cutting process, (c) is a diagram showing two parts obtained in the saw cutting process, and (d) is two parts (main) in which a folded portion is formed by the folding process. It is a figure which shows a member. FIG. 10 is a cross-sectional view taken along line BB in FIG. 9A, and FIG. 11 is a cross-sectional view showing a folded portion formed at the end of the peripheral wall of the passenger seat-side open cross-section portion of the main member.

  In this main member manufacturing method, an aluminum alloy circular tubular extruded shape 100 ′ having a normal circular shape with no recess 100a is used as the aluminum alloy circular tubular extruded shape forming the main member. It is done. First, the press shearing step shown in FIG. 9A will be described. The central portion in the axial direction of the tubular extruded shape 100 ′ is press-sheared along a predetermined length axial direction and cut into a slit shape (FIG. 9). 10). In this case, the press shearing is performed so that the edge-cutting portions for facilitating the processing of the folded portion described later are formed at both ends. W1 'indicates the cut press sheared part.

  Next, the saw cutting process shown in FIG. 9 (b) will be described. Both ends of the press shearing part (trim part) W1 ′ are saw cut along the half circumference of the tubular extruded shape member 100 ′. . W2 represents a saw cutting part. Then, by this saw cutting step, two parts (members) can be obtained at the same time as shown in FIG.

  Next, by performing a folding process for bending the portion of the press shearing portion W ′ inward, as shown in FIG. 9D, the driver side hollow cross-sectional portion 11 and the end portion of the peripheral wall extending in the axial direction are formed. The main member 10 having the passenger seat side open section 12 (see FIG. 11) in which the folded portion 12b is formed is obtained. Thus, the passenger seat side open section 12 of the main member 10 is formed with the folded portion 12b toward the axial center at the end of the peripheral wall extending in the axial direction. For example, it is difficult for an operator to touch the tip of the folded portion 12b, and it is possible to prevent a cut from being caused by the contact. It should be noted that a folded portion may be formed at the end of the peripheral wall of the main member on the passenger seat side open cross-section formed by the recessed tubular extruded shape member 100.

1, 1 '... Aluminum alloy instrument panel reinforcement structure 10 ... Main member
DESCRIPTION OF SYMBOLS 11 ... Driver seat side hollow cross-section part 12 ... Passenger seat side open cross-section part 12a ... Peripheral wall edge part 12b ... Folding part 20, 20 '... Connection stay 20a, 20a' ... Upper end part 20b, 20b '... Lower end part 30, 30' ... Connecting stays 40a, 40b ... Brackets 100, 100 '... Aluminum alloy circular tubular extrusions 100a ... Recesses W1, W1' ... Press shearing parts W2 ... Saw cutting parts

Claims (9)

  An instrument panel reinforcing member structure for an automobile made of aluminum alloy, comprising a main member that extends in the vehicle body width direction and has both axial ends attached to the vehicle body frame directly or via a bracket, the main member being a hollow extrusion made of aluminum alloy Formed integrally with the driver-seat-side hollow cross-section formed by cutting a part of the driver-seat-side hollow cross-section that forms the driver-seat-side portion and the aluminum alloy hollow extruded profile. An instrument panel reinforcing material structure for an automobile made of aluminum alloy, characterized in that it has a passenger seat side open cross-section constituting a passenger seat side portion.   One end portion is joined to a step portion between the driver side hollow cross-section portion and the passenger seat side open cross-section portion, and the other end portion is provided with a connecting stay made of aluminum alloy that is connected to the vehicle body floor. 2. The instrument panel reinforcement structure for automobiles made of aluminum alloy according to claim 1.   The one end of the connecting stay is joined so as to block the hollow opening of the stepped portion at the stepped portion of the driver seat side hollow cross section and the passenger seat side open cross section. The instrument panel reinforcing material structure for automobiles made of aluminum alloy according to claim 2.   The said main member is attached to the said vehicle body frame so that the said passenger seat side open cross-section part may become the attitude | position which protrudes upwards in a vehicle body height direction, The any one of Claims 1-3 characterized by the above-mentioned. Instrument panel reinforcing material structure for automobiles made of the described aluminum alloy.   The instrument panel reinforcing material structure for an automobile made of aluminum alloy according to any one of claims 1 to 4, wherein the cross-sectional shape of the main member is a point-symmetric cross-sectional shape centered on an axis.   The cross section of the driver seat side hollow cross section of the main member is substantially circular, and the cross section of the front passenger side open cross section is substantially semicircular. An instrument panel reinforcement structure for automobiles made of an aluminum alloy according to claim 1.   The hollow extruded shape made of an aluminum alloy has groove-shaped recesses formed in two axially-divided outer peripheries at a predetermined length in two axial directions, and the assistant of the main member. The both end portions of the peripheral wall extending in the axial direction of the seat-side open cross section are formed by press-shearing the two concave portions along a predetermined length axial direction. 2. An instrument panel reinforcing material structure for an automobile made of an aluminum alloy according to item 1.   8. The folded portion that is directed to the axial center side is formed at both end portions of the peripheral wall extending in the axial direction of the open cross-section portion of the main member on the passenger seat side. An instrument panel reinforcing material structure for automobiles made of an aluminum alloy as described in 1.   The aluminum instrument material for automobiles according to any one of claims 1 to 8, wherein the aluminum alloy material used is a 5000 series aluminum alloy material, a 6000 series aluminum alloy material, or a 7000 series aluminum alloy material. Reinforcement structure.

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