Back frame

Abstract

To disclose an example of a back frame capable of restraining reduction in strength, while reducing joining failure of a side frame and a lower frame.SOLUTION: The back frame includes a first flange portion 31 provided at a rear end of the first side frame 3 and extending toward the second side frame 5, the first flange portion 31 being joined to the lower frame 9, a second flange portion 32 extending from an outer edge of the first side frame 3 located forward of the first flange portion 31 toward the second side frame 5, the second flange portion 32 being joined to the lower frame 9, and a third flange portion 33 extending from an outer edge of the first side frame 3 in a range from the first flange portion 31 to the second flange portion 32 toward the lower frame 9, the third flange portion 33 extending continuously over the entire range toward the lower frame 9.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present disclosure relates to a back frame for a vehicle seat. [Background technology]

[0002] For example, in the back frame described in Patent Document 1, a frame-like frame is formed by two side frames, an upper frame, a lower frame, etc. The frames are joined to each other by welding or the like. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2022-167380 Summary of the Invention [Problem to be solved by the invention]

[0004] The present disclosure discloses an example of a back frame that can suppress a decrease in strength while reducing poor joints between a side frame and a lower frame. [Means for solving the problem]

[0005] It is desirable that the back frame of the vehicle seat have at least one of the following constituent features, for example. That is, the constituent elements are a first side frame (3) extending in the vertical direction, a second side frame (5) disposed at a position offset in the seat width direction with respect to the first side frame (3), the second side frame (5) extending in the vertical direction, an upper frame (7) extending in the seat width direction and connecting the upper end side of the first side frame (3) with the upper end side of the second side frame (5), a lower frame (9) extending in the seat width direction and connecting the lower end side of the first side frame (3) with the lower end side of the second side frame (5), and a first frame (9) provided at the rear end side of the first side frame (3) and extending toward the second side frame (5). a second flange portion (32) extending from an outer edge of the first side frame (3) located forward of the first flange portion (31) toward the second side frame (5), the second flange portion (32) being joined to the lower frame (9); and a third flange portion (33) extending from an outer edge of the first side frame (3) in a range from the first flange portion (31) to the second flange portion (32) toward the lower frame (9), the third flange portion (33) extending continuously over the entire range toward the lower frame (9).

[0006] As a result, in this back frame, compared to a configuration in which the first side frame and the lower frame are joined at three or more locations, it may be possible to join the first flange portion (31) and the second flange portion (32) while they are securely in contact with the lower frame (9).

[0007] That is, for example, if there are three joint surfaces, it is difficult to join the three joint surfaces in a state of contact without any gaps due to the accumulation of dimensional variations in the first side frame (3) and the lower frame (9).

[0008] In contrast, in the back frame, the first side frame (3) is joined to the lower frame (9) at the first flange portion (31) and the second flange portion (32), so that the influence of dimensional variations is reduced.

[0009] Therefore, it is possible to reliably bring each of the first flange portion 31 and the second flange portion 32 into contact with the lower frame 9. As a result, it is possible to reliably join each of the first flange portion 31 and the second flange portion 32 to the lower frame 9.

[0010] However, if the first side frame (3) is joined to the lower frame (9) at the first flange portion (31) and the second flange portion (32), there is a risk that the rigidity and strength will be reduced compared to a configuration in which they are joined at three points.

[0011] In contrast, the back frame is provided with a third flange portion 33 that is continuous from the first flange portion 31 to the second flange portion 32. This makes it possible to ensure necessary rigidity and strength even in a configuration in which the first side frame 3 is joined to the lower frame 9 at the first flange portion 31 and the second flange portion 32.

[0012] The back frame may have the following configuration. That is, it is desirable that the extension dimension of the first flange portion 31 and the extension dimension of the second flange portion 32 are larger than the extension dimension of the third flange portion 33. It is desirable that the joint surface between the first flange portion 31 and the lower frame 9 and the joint surface between the second flange portion 32 and the lower frame 9 are flat surfaces. Note that the joint portion between the second side frame 5 and the lower frame 9 may have the same configuration as the joint portion between the first side frame 3 and the lower frame 9.

[0013] Incidentally, the symbols in each of the parentheses above are examples showing the correspondence with the specific configurations, etc. described in the embodiments described below, and the present disclosure is not limited to the specific configurations, etc. shown by the symbols in the parentheses above. [Brief explanation of the drawings]

[0014] [Figure 1]FIG. 2 is a diagram showing a back frame according to the first embodiment. [Figure 2] 4 is a view showing a joint between a first side frame and a lower frame. FIG. [Figure 3] FIG. [Figure 4] FIG. 2 is a view showing a first side frame according to the first embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0015] The following "embodiments of the invention" are examples of embodiments that fall within the technical scope of the present disclosure. In other words, the invention-specific matters described in the claims are not limited to the specific configurations and structures shown in the following embodiments.

[0016] This embodiment is an example in which the back frame according to the present disclosure is applied to a seat (hereinafter referred to as a vehicle seat) mounted on a vehicle such as a car. Arrows and diagonal lines indicating directions are added to each figure to make it easier to understand the relationship between the figures and the shapes of components or parts.

[0017] Therefore, the back frame is not limited to the direction indicated in each drawing. The direction indicated in each drawing is the direction when the vehicle seat according to the present embodiment is assembled to a vehicle. Drawings indicated with diagonal lines do not always represent cross-sectional views.

[0018] At least one member or part that is described with a reference numeral is provided unless otherwise specified, such as "one." In other words, unless otherwise specified, such as "one," the member may be provided in two or more pieces. The back frame shown in the present disclosure is provided in at least one piece. The components, such as the parts or portions, are also numbered and described, and at least one of the structural portions shown.

[0019] (First embodiment) <1.Back frame overview> 1, the back frame 1 is a frame-like frame that constitutes the framework of the seat back 2. The seat back 2 is a portion that supports the back of a seated occupant.

[0020] The back frame 1 includes at least a first side frame 3, a second side frame 5, an upper frame 7, and a lower frame 9. The first side frame 3 and the second side frame 5 are strength members that extend substantially in the vertical direction.

[0021] The second side frame 5 is disposed at a position offset in the seat width direction (to the left in FIG. 1) with respect to the first side frame 3. The upper frame 7 is a strength member that extends in the seat width direction and connects the upper end sides of the first side frame 3 and the second side frame 5.

[0022] The lower frame 9 is a strength member that extends in the seat width direction and connects the lower end sides of the first side frame 3 and the second side frame 5. In this embodiment, the first side frame 3, the second side frame 5, the upper frame 7, and the lower frame 9 are made of metal, and these frames are joined by laser welding.

[0023] <2. Structure of the joint between the side frame and the lower frame> The configuration of the joint between the first side frame 3 and the lower frame 9 is the same as the configuration of the joint between the second side frame 5 and the lower frame 9.

[0024] That is, the two components are substantially symmetrical with respect to an imaginary line that crosses the center in the extension direction of the lower frame 9. The following description will be given of the configuration of the joint portion (part A in FIG. 1) between the first side frame 3 and the lower frame 9.

[0025] The first side frame 3 and the lower frame 9 are joined to each other at least at two locations as shown in Fig. 2. Note that the thick solid lines W1 and W2 shown in Fig. 2 indicate weld marks caused by laser welding.

[0026] As shown in FIG. 3, a first flange portion 31, a second flange portion 32, a third flange portion 33, etc. are provided on the lower end side of the first side frame 3, i.e., the portion of the first side frame 3 that is joined to the lower frame 9.

[0027] The first flange portion 31 is provided at the rear end of the first side frame 3 and extends toward the second side frame 5 (to the left in this embodiment). The first flange portion 31 is joined to a first joined portion 91 of the lower frame 9.

[0028] The second flange portion 32 is a portion that extends toward the second side frame 5 (to the left in this embodiment) from an outer edge of the first side frame 3 that is located further forward than the first flange portion 31. The second flange portion 32 is joined to a second joined portion 92 of the lower frame 9.

[0029] As shown in Figure 4, the third flange portion 33 is a portion that extends from the outer edge of the range C of the outer edge of the first side frame 3, which range extends from the first flange portion 31 to the second flange portion 32, toward the lower frame 9 (to the left in this embodiment).

[0030] The third flange portion 33 extends continuously toward the lower frame 9 (to the left in this embodiment) throughout the entire range C. Note that the extension dimension L1 of the first flange portion 31 and the extension dimension L2 of the second flange portion 32 are greater than the extension dimension L3 of the third flange portion 33.

[0031] The joint surface between the first flange portion 31 and the lower frame 9 and the joint surface between the second flange portion 32 and the lower frame 9 are configured as flat surfaces. The first flange portion 31, the second flange portion 32, and the third flange portion 33 are integrally formed with the first side frame 3 by applying plastic processing such as press working to steel plates.

[0032] 3. Features of the back frame according to this embodiment In the back frame 1 of this embodiment, compared to a configuration in which the first side frame 3 and the lower frame 9 are joined at three or more locations, for example, it may be possible to join the first flange portion 31 and the second flange portion 32 while ensuring that they are in contact with the lower frame 9.

[0033] That is, for example, if there are three joint surfaces, it is difficult to join the three joint surfaces in a state of contact without any gaps due to the accumulation of dimensional variations in the first side frame 3 and the lower frame 9.

[0034] In contrast to this, in the back frame 1, the first side frame 3 is joined to the lower frame 9 at the first flange portion 31 and the second flange portion 32, so the influence of dimensional variations is reduced.

[0035] Therefore, it may be possible to reliably bring each of the first flange portion 31 and the second flange portion 32 into contact with the lower frame 9. As a result, it may be possible to reliably join each of the first flange portion 31 and the second flange portion 32 to the lower frame 9.

[0036] However, if the first side frame 3 is joined to the lower frame 9 at the first flange portion 31 and the second flange portion 32, there is a risk that the rigidity and strength will be reduced compared to a configuration in which they are joined at three points.

[0037] In contrast, the back frame 1 is provided with a third flange portion 33 that is continuous over a range C from the first flange portion 31 to the second flange portion 32. This makes it possible to ensure the necessary rigidity and strength even in a configuration in which the first side frame 3 is joined to the lower frame 9 at the first flange portion 31 and the second flange portion 32.

[0038] (Other embodiments) In the above-described embodiment, the first side frame 3 and the lower frame 9 are joined by laser welding. However, the present disclosure is not limited to this. That is, the present disclosure may also be configured such that the first side frame 3 and the lower frame 9 are joined by an adhesive, for example.

[0039] In the above-described embodiment, the vehicle seat according to the present disclosure is applied to a vehicle. However, the application of the invention disclosed in this specification is not limited thereto. That is, the present disclosure can also be applied to seats used in vehicles such as railway cars, ships, and aircraft, as well as stationary seats used in theaters, homes, etc.

[0040] Furthermore, the present disclosure is not limited to the above-described embodiments as long as it is consistent with the spirit of the disclosure described in the above-described embodiments. Therefore, a configuration in which at least two of the above-described embodiments are combined, or a configuration in which the illustrated Any of the constituent elements or constituent elements described with reference numerals may be eliminated. [Explanation of symbols]

[0041] 1... Back frame 2... Seat back 3... First side frame 5... Second side frame 7... Upper frame 9... Lower frame 31... First flange 32... Second flange 33... Third flange 91... 1st joined part 92…Second joined part

Claims

1. In a back frame of a vehicle seat, a first side frame extending in the vertical direction; a second side frame disposed at a position offset in a seat width direction relative to the first side frame and extending in a vertical direction; an upper frame extending in the seat width direction and connecting an upper end side of the first side frame and an upper end side of the second side frame; a lower frame extending in a seat width direction and connecting a lower end side of the first side frame and a lower end side of the second side frame; a first flange portion provided on a rear end side of the first side frame, extending toward the second side frame, and joined to the lower frame; a second flange portion extending from an outer edge of the first side frame that is positioned forward of the first flange portion toward the second side frame, the second flange portion being joined to the lower frame; a third flange portion extending from an outer edge of the first side frame in a range from the first flange portion to the second flange portion toward the lower frame, the third flange portion extending continuously toward the lower frame over the entire range; A back frame with.

2. The back frame according to claim 1 , wherein the extension dimension of the first flange portion and the extension dimension of the second flange portion are larger than the extension dimension of the third flange portion.

3. The back frame according to claim 1 or 2, wherein a joint surface between the first flange portion and the lower frame and a joint surface between the second flange portion and the lower frame are flat surfaces.

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