Rear gate reinforcement structure
The rear gate reinforcement structure uses overlapping metal plate members to maintain rigidity and reduce weight, addressing the inefficiency of traditional reinforcement methods by optimizing plate thickness distribution.
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- NISSAN MOTOR CO LTD
- Filing Date
- 2024-11-05
- Publication Date
- 2026-05-15
AI Technical Summary
Existing rear gate reinforcement structures increase weight due to the need for thicker metal plates to ensure rigidity, compromising mass efficiency.
A reinforcement structure for the rear gate using two overlapping metal plate members forming a hat-shaped protrusion, where the top surface and side walls of the protrusion are composed of different plate members, ensuring rigidity at the required areas while reducing thickness elsewhere, thereby maintaining mass efficiency.
The structure enhances rigidity and bending resistance without increasing weight, allowing for efficient reinforcement of the rear gate by optimizing the plate thickness distribution.
Smart Images
Figure JP2024039297_15052026_PF_FP_ABST
Abstract
Description
Rear gate reinforcement structure
[0001] The present invention relates to a reinforcement structure for a rear gate.
[0002] In Patent Document 1 below, the structure of a rear gate (back door) at the rear of a vehicle is disclosed. This vehicle is a hatchback type vehicle, and the rear gate is formed so as to bend downward in a side view of the vehicle in the vicinity of the lower end of the glass holding frame portion. And a reinforcing member provided with a protruding strip portion having a substantially hat-shaped cross section on the indoor side is attached to this bent portion to reinforce the rear gate.
[0003] Japanese Patent No. 4712854
[0004] In the bent portion of the rear gate described in Patent Document 1 above, since a bending stress that extends the bend acts, it is widely practiced to reinforce this bent portion. As described above, the reinforcing member having a protruding strip portion having a substantially hat-shaped cross section is generally formed by bending a single metal plate member into a hat shape. However, in order to ensure the rigidity of the protruding strip portion, the plate thickness of the metal plate member forming the reinforcing member is required, and as a result, the weight of the reinforcing member increases, so there is room for improvement in terms of mass. An object of the present invention is to provide a rear gate reinforcement structure capable of efficiently reinforcing the rear gate in terms of mass.
[0005] One aspect of the present invention is a reinforcement structure for a rear gate provided with a glass holding frame portion at the upper part, a lock member attachment portion at the lower part, and a bent portion provided so that the whole bends downward in a side view of the vehicle in the vicinity of the lower end of the glass holding frame portion. A reinforcing member having a protruding strip portion having a substantially hat-shaped cross section protruding to the indoor side and having a flange portion joined to the rear gate panel is provided at the bent portion, and the top surface portion of the protruding strip portion of the reinforcing member and one side wall portion connected from the top surface portion are composed of a first plate member, and the top surface portion of the protruding strip portion and the other side wall portion connected from the top surface portion are composed of a second plate member, and the gist is that the first plate member and the second plate member are joined in a state where they are overlapped with a predetermined width on the hat-shaped top surface portion.
[0006] According to one aspect of the present invention, the rigidity of hat-shaped protrusions where rigidity is required can be ensured, while the plate thickness of plate members constituting flanges and other portions where high rigidity is not required can be reduced, thereby enabling efficient reinforcement of the rear gate in terms of mass. The objectives and advantages of the present invention are embodied and achieved using the elements and combinations thereof set forth in the claims. Both the above general description and the following detailed description are merely illustrative and explanatory and should be understood not to limit the present invention as in the claims.
[0007] This is a three-view drawing showing the panel components of the rear gate. This is a detailed view of the reinforcing member in Figure 1. This is a cross-sectional view taken along line A-A in Figure 2.
[0008] Embodiments of the present invention will be described below with reference to the drawings. Note that the drawings are schematic and may differ from actual ones. Figure 1 shows, as an example, the panel elements of a rear gate 1 used in a hatchback type vehicle, with Figure 1a being a front view and Figure 1b being a right side view. The rear gate 1 is a lift-up door, i.e., a hatch, that covers the rear end of the passenger compartment (cargo compartment) of the vehicle. In a hatchback type vehicle, when viewed from the side of the vehicle, the entire rear gate is formed to be angled downward from the front to the rear of the vehicle, and a glass retaining frame portion 11 for fitting a rear glass window (not shown) is provided at the top. Furthermore, the lower rear portion of the rear gate 1 is formed to be approximately vertically downward relative to the glass retaining frame portion 11, which is angled downward toward the rear of the vehicle when viewed from the side of the vehicle. Therefore, the lower portion of the rear gate 1 is bent downward relative to the upper portion, and a bent portion 1a is formed at the boundary. Furthermore, a locking member mounting portion 12 is provided in the center of the lower part (lower end) of the rear gate 1 in the vehicle width direction, and a locking member (not shown) for fixing the lower end of the rear gate 1 to the vehicle body is attached to this locking member mounting portion 12.
[0009] In the bent portion 1a of the rear gate 1, a force acting diagonally upward and towards the rear of the vehicle, such as a bending stress that straightens the bend, acts in the right side view of Figure 1b. Therefore, protruding portions 3 are provided on both sides of the bent portion 1a in the vehicle width direction, projecting towards the interior of the vehicle and extending in the vertical direction of the vehicle, as a reinforcing structure for the rear gate 1. The protruding portion 3 has a roughly hat-shaped cross-section, with a top surface portion 3b that constitutes the top surface of the hat and side wall portions 3a connected to both sides thereof. This protruding portion 3 is provided on a reinforcing member 5, to which a roughly flat (flat plate) flange portion 4 other than the protruding portion 3 is joined (connected) to the rear gate panel 2, and this reinforcing member 5 is attached to the rear gate panel 2, thereby providing the rear gate 1. As shown in Figure 2, this reinforcing member 5 is composed of two metal plate members 6 and 7. These plate members are a plate member 6 on the outside in the vehicle width direction (hereinafter referred to as the first plate member) and a plate member 7 on the inside in the vehicle width direction (hereinafter referred to as the second plate member), and the two plate members form a projection 3 with a roughly hat-shaped cross-section. Specifically, as shown in the cross-sectional view of Figure 3, the inside end of the first plate member 6 in the vehicle width direction forms one side wall portion 3a (outside in the vehicle width direction) and the top surface portion 3b of the hat-shaped projection 3, and the outside end of the second plate member 7 in the vehicle width direction forms the other side wall portion 3a (outside in the vehicle width direction) and the top surface portion 3b of the hat-shaped projection 3. At the hat-shaped top surface portion 3b, the first plate member 6 and the second plate member 7 are joined (connected) in a state where they overlap by a predetermined width. For example, welding is used to join the two.
[0010] The flange portion 4 of the reinforcing member 5 is the portion of the first plate member 6 and the second plate member 7 other than the portion where the hat-shaped projection 3 is formed. For example, the flange portion 4 of the first plate member 6 is hemmed to the rear gate panel 2 at its outer edge in the vehicle width direction. On the other hand, the inner flange portion 4 of the second plate member 7 in the vehicle width direction is welded to the rear gate panel 2 at a location not shown in the figure. The centroid G of the cross-section of the reinforcing member 5, composed of the first plate member 6 and the second plate member 7, is located at the position shown in Figure 3, that is, near the bottom of the cross-section of the hat-shaped projection 3 (the base end side of the side wall portion 3a). The top surface portion 3b of the hat-shaped projection 3, where the first plate member 6 and the second plate member 7 are joined, has high rigidity because the plate members are overlapped. The rigidity required in this reinforcing member 5 is in the hat-shaped protrusion 3. By joining the two metal plate members, the first plate member 6 and the second plate member 7, at the top surface 3b of the protrusion 3, the rigidity of the protrusion 3, including the top surface 3b, can be efficiently ensured while suppressing an increase in the weight of the reinforcing member 5. Furthermore, by increasing the rigidity of the top surface 3b, which is far from the cross-sectional center G located near the bottom of the hat shape, the second moment of area of the reinforcing member 5 can be increased, thereby efficiently increasing the overall bending rigidity while suppressing an increase in the weight of the reinforcing member 5. On the other hand, the parts of the first plate member 6 and the second plate member 7 other than the protrusion 3, where the flange portion 4 is joined to the rear gate panel 2, do not require such high rigidity. In other words, since the rigidity of the hat-shaped protrusion 3 can be increased without increasing the plate thickness of the first plate member 6 and the second plate member 7, it is possible to reduce the mass of the reinforcing member 5.
[0011] Of the two metal plate members that constitute the reinforcing member 5, the first plate member 6, which is positioned on the outer side in the vehicle width direction, has multiple circular holes 9 formed in the outer side wall portion 3a of the hat-shaped protrusion 3 in the vehicle width direction, and nuts (weld nuts) 8 are fixed to the inner part of the hat shape of each circular hole 9. For example, the two upper circular holes 9 shown in Figure 3 are for attaching brackets for gas stays (dampers), and the two lower circular holes 9 are for attaching brackets for bump rubbers. As shown in Figure 3, the nuts 8 are welded inside the hat-shaped protrusion 3. This is possible because the nuts 8 are welded to the first plate member 6 on the inside of the side wall portion 3a of the hat-shaped protrusion 3 before the first plate member 6 and the second plate member 7 are joined (welded) at the top surface portion 3b of the hat-shaped protrusion 3 to form the reinforcing member 5. For example, if the hat-shaped protrusion 3, i.e., the reinforcing member 5, is formed by bending a single metal plate, it would be difficult to weld the nut 8 inside the protrusion 3, and it could only be attached to the outside of the protrusion 3 (flange portion 4). In other words, in this embodiment, since various parts can be attached to the highly rigid protrusion 3, it is possible to ensure the mounting rigidity of the attached parts.
[0012] Furthermore, in this embodiment, the thickness of the first plate member 6 and the thickness of the second plate member 7 are the same, but it is also possible to make their thicknesses different. For example, as mentioned above, if a component is attached to the first plate member 6 but not to the second plate member 7, it is possible to increase the thickness of the first plate member 6 to ensure the rigidity for attaching the component to the first plate member 6, and set the thickness of the second plate member 7 to be smaller. On the other hand, if the reinforcing member 5 is formed by bending a single metal plate, it is disadvantageous in terms of mass because it is necessary to use a plate member equivalent to the first plate member 6 with a larger thickness for the portion of the second plate member 7. In other words, in this embodiment, it is also possible to optimize the thickness of the reinforcing member 5.
[0013] The rear gate reinforcement structure of the embodiment has been described above, but the present invention is not limited to the configuration described in the above embodiment, and various modifications are possible within the scope of the gist of the present invention. For example, in the above embodiment, a protruding portion 3 with a substantially hat-shaped cross-section is provided on both outer sides in the vehicle width direction at the lower end of the glass holding frame portion 11 of the rear gate 1, protruding inward and extending in the vehicle vertical direction. However, this protruding portion 3 may be provided at any position in the bent portion 1a of the rear gate 1. However, since the bending stress acting on this bent portion 1a causes large bending deformation of the rear gate 1 on both outer sides in the vehicle width direction, it is efficient to provide the protruding portion 3 in this portion.
[0014] In this embodiment, to reinforce a rear gate 1 which has a glass retaining frame portion 11 at the top and a locking member mounting portion 12 at the bottom, and a bent portion 1a near the lower end of the glass retaining frame portion 11 that bends downward when viewed from the side of the vehicle, a reinforcing member 5 is provided at the bent portion 1a, which has a projection portion 3 with a substantially hat-shaped cross-section that protrudes inward and a flange portion 4 that is joined to the rear gate panel 2. The top surface portion 3b of the hat-shaped projection portion 3 of the reinforcing member 5 and one side wall portion 3a connected thereto are made of a first plate member 6, and the top surface portion 3b of the hat-shaped projection portion 3 and the other side wall portion 3a connected thereto are made of a second plate member 7, and the first plate member 6 and the second plate member 7 are joined at the hat-shaped top surface portion 3b. As a result, the rigidity of the hat-shaped projection portion 3, which requires rigidity, can be ensured, and the plate thickness of the plate members that make up the flange portion 4, etc., which do not require high rigidity can be reduced, so that the rear gate 1 can be reinforced efficiently in terms of mass. Furthermore, because the hat-shaped protrusions 3 are continuous in the vertical direction of the vehicle at both ends of the rear gate 1 in the vehicle width direction, the rear gate 1 can be reliably reinforced against bending stress that would stretch the bent portion 1a.
[0015] 1... Rear gate, 2... Rear gate panel, 3... Protruding section, 3a... Side wall section, 3b... Top surface section, 4... Flange section, 5... Reinforcement member, 6... First plate member (first plate member), 7... Second plate member (second plate member), 8... Nut, 9... Circular hole, 11... Glass retaining frame section, 12... Lock member mounting section
Claims
1. A rear gate reinforcing structure having a glass retaining frame at the top and a locking member mounting portion at the bottom, and a bent portion near the lower end of the glass retaining frame that bends downward when viewed from the side of the vehicle, wherein a reinforcing member is provided at the bent portion having a projection with a substantially hat-shaped cross-section that protrudes toward the interior and a flange portion that is joined to the rear gate panel, wherein the top surface of the projection of the reinforcing member and one side wall portion connected thereto are made of a first plate member and the top surface of the projection and the other side wall portion connected thereto are made of a second plate member, and the first plate member and the second plate member are joined at the hat-shaped top surface in a state where they overlap by a predetermined width.
2. The rear gate reinforcing structure according to claim 1, characterized in that the hat-shaped protrusions are continuous in the vertical direction of the vehicle at both ends of the rear gate in the vehicle width direction.