JP7362537B2 - frame structure - Google Patents

Description

TECHNICAL FIELD This disclosure relates to frame structures.

As a conventional frame structure, for example, there is a frame structure used in an underfloor storage type lifting device described in Patent Document 1. In this frame structure, a suspension region on which a retractable tailgate is suspended is provided at a rear end portion of a main frame extending in the front-rear direction of a vehicle such as a truck. The tailgate includes a slide guide attached to the rear end portion of the main frame, and can be driven between a retracted position and a raised/lowered position by engaging a slidable runner with the slide guide. There is.

Japanese Patent Application Publication No. 2012-040896

In vehicles where a retractable tailgate is suspended on the rear end of the main frame, the shape of the rear end of the main frame is adjusted to avoid interference between the main frame and the tailgate, and a certain amount of space is placed in the suspension area of the tailgate. It is necessary to secure space. In conventional frame structures, for example, the rear end of the main frame is cut off at a portion corresponding to the suspension area of the tailgate, and another frame narrower than the main frame is joined to the upper end of the main frame. A structure is adopted in which a reinforcing member is joined to the joint part.

However, in such a frame structure, since another frame is connected to the main frame, the frame cross section becomes discontinuous. For this reason, in order to ensure the strength and rigidity of the frame, it has become necessary to significantly reinforce the joint between the main frame and another frame, resulting in an increase in the weight and cost of the frame structure.

The present disclosure has been made to solve the above problems, and an object of the present disclosure is to provide a frame structure that is lightweight and can construct a suspension area of a retractable tailgate at low cost.

A frame structure according to one aspect of the present disclosure is a frame structure applied to a main frame extending in the front-rear direction of a vehicle, and a retractable tailgate is suspended from a rear end portion of the main frame. A suspension area is provided, and in the suspension area, the lower side of the rear end portion of the main frame is cut out to form a narrow part whose vertical width is smaller than the main body of the main frame. A reinforcing member is coupled to the reinforcing member extending in the longitudinal direction of the vehicle over the narrow portion.

In this frame structure, the lower side of the rear end portion of the main frame is cut out to form a narrow portion that is smaller in vertical width than the main body portion of the main frame. By providing the narrow portion, a certain amount of space can be secured in the suspension area of the main frame, and interference between the main frame and the tailgate can be avoided. Further, in this frame structure, the continuity of the frame cross section is maintained at the rear end portion of the main frame, unlike a structure in which the rear end portion of the main frame is cut and another frame is connected. A reinforcing member that extends from the main body to the narrow part in the longitudinal direction of the vehicle is connected to the main frame. Since a certain level of strength and rigidity can be ensured, reinforcement by reinforcing members can be simplified. Therefore, with this frame structure, the suspension area of the retractable tailgate can be constructed at a lightweight and low cost.

The rear end of the reinforcing member may coincide with the rear end of the main frame. In this case, the strength and rigidity of the rear end portion of the main frame can be further increased by the reinforcing member. Further, by extending the reinforcing member to the rear end of the main frame, it is possible to provide flexibility in the fastening position of the reinforcing member to the main frame. Therefore, it is possible to adjust the fastening position of the reinforcing member to the main frame according to the attachment position of the retractable tailgate suspended in the suspension area, and the ease of mounting the retractable tailgate is improved.

The lower end of the reinforcing member may coincide with the lower end of the main frame in the narrow portion. In this case, it is possible to both improve the strength and rigidity of the rear end portion of the main frame by the reinforcing member and secure sufficient space in the suspension area.

An inner member extending in the longitudinal direction of the vehicle is coupled to the main body of the main frame, and the front end of the reinforcing member is provided with a notch corresponding to the shape of the rear end of the inner member. The rear end may abut against the front end portion of the reinforcing member at the notch. In this case, local cross-sectional changes of the frame can be reduced at the abutting portion between the front end portion of the reinforcing member and the rear end portion of the inner member. Therefore, local stress concentration on the main frame between the inner member and the reinforcing member can be suppressed, and an increase in size and weight of the reinforcing member can be avoided.

According to the present disclosure, a suspension area of a retractable tailgate can be constructed with light weight and low cost.

FIG. 3 is a side view of the frame structure on which the tailgate is suspended. FIG. 1 is a perspective view of a frame structure according to an embodiment of the present disclosure. 3 is a side view of the frame structure shown in FIG. 2. FIG. 4 is a sectional view taken along the line IV-IV in FIG. 3. FIG. 4 is a sectional view taken along the line VV in FIG. 3. FIG. FIG. 3 is an enlarged view of a main part showing a connecting portion between an inner member and a reinforcing member. 4 is a sectional view taken along the line VII-VII in FIG. 3. FIG. FIG. 3 is a side view showing an example of fastening the tailgate. FIG. 7 is a side view showing another example of fastening the tailgate.

Hereinafter, preferred embodiments of a frame structure according to one aspect of the present disclosure will be described in detail with reference to the drawings.

FIG. 1 is a side view of a frame structure on which a tailgate is suspended. A frame structure 1 shown in FIG. 1 is a structure applied to the lower rear part of a vehicle such as a truck having a container, for example.

The retractable tailgate T includes a base part 3 fixed to a frame structure 1, a telescoping rod 4 connected to the base part 3, and a gate panel 5 connected to the tip of the telescoping rod 4 in a bifold state. and a lift arm 6 connected to the gate panel 5. The tailgate T also includes a slide guide 8 attached to the frame structure 1 and a runner (not shown) that is slidable along the slide guide 8. The lift arm 6 and the gate panel 5 can be driven in the longitudinal direction of the vehicle as the runner slides.

As shown in the figure, the tailgate T is suspended in a suspension area B (described later) provided in the frame structure 1. When loading cargo, etc., the telescopic rod 4 extends toward the rear of the vehicle, and after the gate panel 5 advances to the rear of the container, the gate panel 5 is driven upward by the operation of the lift arm 6. After loading the cargo, etc., the gate panel 5 is driven downward by the operation of the lift arm 6, and then the telescopic rod 4 is shortened to its original position, so that the gate panel 5 is retracted to the suspension area B. The bi-fold gate panel 5 may be opened and closed electrically or manually. Further, the gate panel 5 is not limited to a bifold one, and various types can be used.

FIG. 2 is a perspective view of a frame structure according to an embodiment of the present disclosure. 3 is a side view thereof, and FIG. 4 is a sectional view taken along the line IV-IV in FIG. 3. As shown in FIGS. 2 to 4, the frame structure 1 includes a main frame 2 and an inner member 21. As shown in FIGS.

The main frame 2 is a pair of left and right members that constitute the chassis of the vehicle, and extends in the longitudinal direction of the vehicle (only one main frame is shown in FIGS. 2 to 4). The main frame 2 is constructed of a metal profile having a substantially C-shaped cross section, for example. The main body portion 23 of the main frame 2 has a side surface portion 2a, and a top surface portion 2b and a bottom surface portion 2c extending from the upper and lower ends of the side surface portion 2a in the same direction and perpendicular to the side surface portion 2a. The side surface portion 2a is provided with a through hole 2d used for coupling the main frame 2 with other members. In this embodiment, a plurality of through holes 2d are arranged in the extending direction of the main frame 2 in the upper and lower parts of the side surface portion 2a.

The inner member 21 is a member that reinforces the main body part 23 of the main frame 2, and extends along the longitudinal direction of the main body part 23. The inner member 21 is configured, for example, by a metal profile having a substantially L-shaped cross section. The inner member 21 has, for example, a side surface portion 21a and a side surface portion 21b having approximately the same width as the upper surface portion 2b of the main frame 2. Similar to the main frame 2, the side surface portion 21b is provided with a through hole 21d used for coupling the inner member 21 with other members. The side surface portion 21a extends from one end of the side surface portion 21b in the width direction in a direction perpendicular to the side surface portion 21b.

In this embodiment, the inner member 21 is arranged at the upper and lower parts of the side surface portion 2a of the main body portion 23 in the main frame, respectively. In the upper inner member 21, the side surface portion 21b is in contact with the side surface portion 2a of the main body portion 23, and the side surface portion 21a is in contact with the upper surface portion 2b of the main body portion 23. Further, in the lower inner member 21, the side surface portion 21b is in contact with the side surface portion 2a of the main body portion 23, and the side surface portion 21a is in contact with the bottom surface portion 2c of the main body portion 23. The upper and lower inner members 21 are firmly connected to the main body portion 23 of the main frame 2, for example, by bolt-nut fastening using through holes 2d and 21d.

Next, the configuration of the rear end portion of the main frame 2 will be described in detail.

The rear end portion of the main frame 2 is provided with a suspension region B for the above-mentioned retractable tailgate T. A narrow portion 24 having a smaller vertical width than the main body portion 23 of the main frame 2 is formed at the rear end portion of the main frame 2 in correspondence with the suspension region B. The narrow portion 24 is formed by cutting out the lower side of the rear end portion of the main frame 2 . In this embodiment, the notch F1 formed on the lower side of the rear end portion of the main frame 2 has a substantially rectangular shape when the main frame 2 is viewed from the side.

The dimensions of the cutout portion F1 may be appropriately designed in consideration of the strength and dimensions of the main frame 2, the weight and dimensions of the tailgate T, and the height of the vehicle above the ground with the tailgate T placed in a flower arrangement. In the present embodiment, the length of the notch F1 in the front-rear direction is larger than the length of the tailgate T suspended in the suspension area B in the retracted state, and the length of the cut-out part F1 in the vertical direction is larger than the length of the tailgate T in the stored state. is approximately half or less of the vertical width of the side surface portion 2a of the main frame 2.

In the cutout portion F1, the lower portion of the side surface portion 2a of the main frame 2 and the bottom surface portion 2c are cut out. Therefore, in the narrow portion 24, as shown in FIG. It extends to the rear end 2e of the frame 2. Note that the corners and corner portions formed in the side surface portion 2a of the main frame 2 by the notch portion F1 may be chamfered or chamfered.

In forming the narrow portion 24, a reinforcing member 25 is coupled to the main frame 2 and extends from the main body portion 23 to the narrow portion 24 in the longitudinal direction of the vehicle. The reinforcing member 25 is a member that supplements the strength and rigidity of the narrow portion 24 of the main frame 2, and is made of, for example, a metal profile having a substantially C-shaped cross section. Specifically, the reinforcing member 25 has a side surface portion 25a having a width corresponding to the vertical width of the narrow portion 24, an upper surface portion 25b having a width approximately equal to the upper surface portion 2b of the main frame 2, and a bottom surface portion of the main frame 2. 2c and a bottom portion 25c having approximately the same width. Similar to the main frame 2, a through hole 25d used for coupling the reinforcing member 25 to other members is provided in the upper part of the side surface portion 25a. The top surface portion 25b and the bottom surface portion 25c extend from the upper and lower ends of the side surface portion 25a in the same direction and perpendicular to the side surface portion 25a.

When connecting the reinforcing member 25 to the main frame 2, the side surface portion 25a is in contact with the side surface portion 2a of the main frame 2, and the top surface portion 25b is in contact with the top surface portion 2b of the main frame 2 (see FIG. 5). . The reinforcing member 25 is firmly connected to the narrow portion 24 of the main frame 2 by, for example, bolt-nut fastening using the through holes 2d and 25d.

The longitudinal dimension of the reinforcing member 25 can be appropriately designed in consideration of securing the strength and rigidity of the narrow portion 24, securing the space of the suspension region B, reducing the weight of the frame structure 1, etc. In this embodiment, as shown in FIG. 3, the rear end 25e side of the reinforcing member 22 extends to the position of the rear end 2e of the main frame 2, and the rear end 25e of the reinforcing member 25 and the rear end of the main frame 2 2e matches. Further, in the present embodiment, the sum of the vertical width of the side surface portion 25a of the reinforcing member 25 and the thickness of the top surface portion 25b and the bottom surface portion 25c is equal to the vertical width of the side surface portion 2a of the main frame 2 in the narrow width portion 24. We are doing so. As a result, the lower end 25f of the reinforcing member 25 and the lower end 2f of the main frame 2 in the narrow portion 24 are aligned.

Further, as shown in FIG. 6, the front end portion 25g side of the reinforcing member 25 is located forward of the boundary portion between the main body portion 23 and the narrow portion 24. The front end portion 25g of the reinforcing member 25 is provided with a cutout portion F2 corresponding to the shape of the rear end portion 21e of the inner member 21 in side view. In this embodiment, the notch F2 is formed into a rectangular shape in side view by cutting out the upper side of the front end portion 25g of the reinforcing member 25. The length of the notch F2 in the vertical direction is approximately equal to the vertical width of the inner member 21. The length of the notch F2 in the front-rear direction is not particularly limited, but is such that, for example, the front end portion 25g of the reinforcing member 25 is located between the upper and lower inner members 21 over a certain length.

Such a notch F2 functions as a relief part for the rear end portion 21e of the inner member 21 when the reinforcing member 25 is arranged. In this embodiment, the rear end portion 21e of the upper inner member 21 is located in the region cut out by the cutout portion F2, and abuts against the front end portion 25g of the reinforcing member 25. In the rear end portion 21e of the inner member 21 and the front end portion 25g of the reinforcing member 25, the side surface portion 21b of the inner member 21 and the side surface portion 25a of the reinforcing member 25 are continuous, as shown in FIGS. The side surface portion 21a of the reinforcing member 21 and the upper surface portion 25b of the reinforcing member 25 are continuous. Therefore, compared to the case where the rear end portion 21e of the inner member 21 and the front end portion 25g of the reinforcing member 25 are spaced apart, local cross-sectional changes of the frame are reduced.

As explained above, in this frame structure 1, by cutting out the lower side of the rear end portion of the main frame 2, a narrow portion 24 having a smaller vertical width than the main body portion 23 of the main frame 2 is formed. There is. By providing the narrow portion 24, a certain amount of space can be secured in the suspension region B of the main frame 2, and interference between the main frame 2 and the tailgate T can be avoided. Furthermore, in this frame structure 1, unlike a structure in which the rear end portion of the main frame 2 is cut and another frame is connected, the continuity of the L-shaped cross-sectional portion 50 is maintained at the rear end portion of the main frame 2. Ru. A reinforcing member 22 extending in the longitudinal direction of the vehicle from the main body portion 23 to the narrow portion 24 is coupled to the main frame 2. Since constant strength and rigidity of the rear end portion can be ensured by maintaining the above, reinforcement by the reinforcing member 22 can be simplified. Therefore, with this frame structure 1, the suspension region B of the tailgate T can be constructed with light weight and low cost.

Furthermore, in this frame structure 1, since the upper surface portion 2b of the main body portion 23 and the upper surface portion 2b of the narrow width portion 24 are a continuous body of the main frame 2, there is a gap between the main frame portion 23 and the narrow width portion 24. The upper surface portion 2b is designed to be flat. Therefore, there is no need to provide a new member (such as an outer member) for flattening the upper surface portion 2b.

Further, in this embodiment, the rear end 25e of the reinforcing member 25 is aligned with the rear end 2e of the main frame 2. Thereby, the strength and rigidity of the rear end portion of the main frame 2 can be further increased by the reinforcing member 25. Further, by extending the reinforcing member 25 to the rear end 2e of the main frame 2, the position of fastening the reinforcing member 25 to the main frame 2 can be provided with a degree of freedom. Therefore, it is possible to adjust the fastening position of the reinforcing member 25 to the main frame 2 according to the fixing area X of the tailgate T suspended in the suspension area B, and the ease of mounting the tailgate T is improved. .

In the example of FIG. 8 , the tailgate T is coupled to the narrow portion 24 at a fixed region X located in front of the narrow portion 24 . Further, in the example of FIG. 9, the tailgate T is coupled to the narrow portion 24 at a plurality of fixed regions X located in front of the narrow portion 24, behind the narrow portion 24, and in the middle thereof. For these various types of tailgates T, the rear end 25e of the reinforcing member 25 extends to the rear end 2e of the main frame 2, so that even if the through hole 2d is blocked in the fixing region X, The main frame 2 and the reinforcing member 25 can be fastened at any position other than the fixed area X.

Furthermore, in the present embodiment, the lower end 25f of the reinforcing member 25 coincides with the lower end 2f of the main frame 2 in the narrow portion 24. Therefore, it is possible to both improve the strength and rigidity of the rear end portion of the main frame 2 by the reinforcing member 25 and secure sufficient space in the suspension region B.

Further, in this embodiment, the inner member 21 extending in the longitudinal direction of the vehicle is coupled to the main body portion 23 of the main frame 2, and the rear end portion 21e of the inner member 21 is connected to the front end portion 25g of the reinforcing member 25. A notch F2 corresponding to the shape is provided. The rear end portion 21e of the inner member 21 is abutted against the front end portion 25g of the reinforcing member 25 at the cutout portion F2. With this configuration, it is possible to reduce local cross-sectional changes of the frame at the abutting portion between the front end portion 25g of the reinforcing member 25 and the rear end portion 21e of the inner member 21. Therefore, it is possible to suppress local stress concentration from occurring in the main frame 2 between the inner member 21 and the reinforcing member 25, and it is possible to avoid increasing the size and weight of the reinforcing member 25.

Although preferred embodiments of the present disclosure have been described above, the present disclosure is not necessarily limited to the embodiments described above, and various changes can be made without departing from the gist thereof. For example, in the above embodiment, the rear end 25e of the reinforcing member 25 is aligned with the rear end 2e of the main frame 2, but the rear end 25e of the reinforcing member 25 does not necessarily extend to the position of the rear end 2e of the main frame 2. It doesn't have to be. Further, in the embodiment described above, the lower end 25f of the reinforcing member 25 coincides with the lower end 2f of the narrow part 24 of the main frame 2, but the lower end 25f of the reinforcing member 25 does not necessarily correspond to the lower end 2f of the narrow part 24 of the main frame 2. It does not have to coincide with the lower end 2f in . That is, the lower end 25f of the reinforcing member 25 may be located below the lower end 2f of the narrow portion 24 of the main frame 2, or may be located above the lower end 2f.

Furthermore, in the embodiment described above, the front end portion 25g of the reinforcing member 25 is provided with the notch portion F2 corresponding to the shape of the rear end portion 21e of the inner member 21, but the notch portion F2 is not necessarily provided. It's okay. In this case, the front end portion 25g of the reinforcing member 25 without the notch portion F2 may be directly abutted against the rear end portion 21e of the inner member 21.

DESCRIPTION OF SYMBOLS 1... Frame structure, 2... Main frame, 2e, 25e... Rear end, 2f, 25f... Lower end, 21... Inner member, 21e... Rear end part, 25... Reinforcement member, 25g... Front end part, 23... Main body part, 24... Narrow portion, B... Suspension area, F2... Notch, T... Tailgate (retractable tailgate).

Claims (4)

A frame structure applied to a main frame extending in the longitudinal direction of a vehicle,
A suspension area on which a retractable tailgate is suspended is provided at a rear end portion of the main frame,
In the suspension region, the lower side of the rear end portion of the main frame is cut out to form a narrow portion having a vertical width smaller than the main body portion of the main frame,
A frame structure in which a reinforcing member extending in the longitudinal direction of the vehicle from the main body portion to the narrow width portion is coupled to the main frame. The frame structure according to claim 1, wherein a rear end of the reinforcing member is coincident with a rear end of the main frame. The frame structure according to claim 1 or 2, wherein a lower end of the reinforcing member is coincident with a lower end of the main frame in the narrow portion. An inner member extending in the longitudinal direction of the vehicle is coupled to the main body portion of the main frame,
A notch portion corresponding to the shape of the rear end portion of the inner member is provided in the front end portion of the reinforcing member,
4. The frame structure according to claim 1, wherein the rear end of the inner member abuts against the front end portion of the reinforcing member at the notch.

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