JP2009255665A - Cross member of vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce the whole weight of a chassis frame, while securing rigidity and strength of a vehicle body, regarding a cross member of a vehicle. <P>SOLUTION: This cross member 9b is fixed to a pair of right and left side rails 8 extending in the vehicle longitudinal direction, and forms the stepped chassis frame by connecting side rails 8 in the vehicle width direction. The cross member 9b is provided with a first cross member 6 of a closed section structure for bearing torsion torque between the side rails 8 and a second cross member 7 for bearing tensile force between the side rails 8. In the first cross member 6, a first member 1 is fixed to the one side rail 8 and a second member 2 is fixed to the other side rail 8, and the first member 1 and the second member 2 are mutually fitted to form a fitting part 5. In the fitting part 5, the first member 1 and the second member 2 are made slidable in the vehicle width direction and relative displacement in the peripheral direction is regulated. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a cross member constituting a chassis frame of a vehicle.

  Conventionally, as a chassis frame of a vehicle, a pair of left and right side rails extending in the vehicle front-rear direction and connected in the vehicle width direction by a cross member and formed in a ladder shape is widely used. Such a cross member of the chassis frame mainly has a function of maintaining a distance between the left and right side rails against the tensile force in the vehicle width direction, and a twist of the side rails against a moment about the cross member as a rotation axis. It has a function to suppress

  For example, in Patent Document 1, a cross member having a substantially U-shaped cross section is provided between a pair of side members (side rails) provided along the longitudinal direction of the vehicle body so as to open to one side in the longitudinal direction of the vehicle body. The arranged chassis frame structure is shown. In this technique, the side member and the cross member are connected via a gusset to increase the rigidity of the joint, particularly the torsional rigidity in the rotational direction about the cross member.

Patent Document 2 shows a structure in which a pipe-shaped cross member is installed between a pair of left and right side frames (side rails). In this technique, the cross-sectional shape of the cross member is a circular closed cross-section, thereby improving the cross-sectional performance and improving the member rigidity.
As described above, various shapes have been proposed for the cross member of the chassis frame in accordance with the use and purpose of use of the vehicle.
JP 2003-252235 A Japanese Patent Laid-Open No. 9-222102

Incidentally, the rigidity and strength required for the cross member are set according to the running performance of the vehicle body, for example, the allowable displacement in the vehicle width direction. Therefore, the size of the cross member has to be increased in order to increase the rigidity and strength of a vehicle that is expected to have a high load, and the vehicle body weight of the entire chassis frame increases.
In particular, since two types of load, tensile force in the vehicle width direction and torsional torque, act on the cross member as described above, considering the maximum load of both, the strength of the member is adjusted to one of the larger loads. And the shape must be designed. In the cross member, the torsional torque tends to be larger than the tensile force. Therefore, for example, when the cross member is designed based on the tensile force, the structure is insufficient in rigidity with respect to the torsion torque, or when the torsion torque is used as a reference, the structure becomes stronger than necessary with respect to the tensile force. Become.

Thus, in the cross member of a vehicle, the performance with respect to required rigidity and intensity | strength tends to become excessive, and there exists a subject that physical size and weight tend to increase.
The present invention has been made in view of such a problem, and an object of the present invention is to provide a vehicle cross member that can reduce the weight of the entire chassis frame while ensuring the rigidity and strength of the vehicle body.

  In order to achieve the above object, a cross member of a vehicle of the present invention according to claim 1 is a flange that extends in the vehicle front-rear direction and extends inwardly in the vehicle width direction from the upper and lower ends of a vertically oriented web. A cross member of a vehicle that is fixed to a pair of left and right side rails each having a U-shaped cross section and that connects the side rails in the vehicle width direction to form a ladder-type chassis frame, The first cross member (pipe cross) having a closed cross-sectional structure that bears the torsion torque between the pair of left and right side rails and suppresses the torsion of the side rails, and bears the tensile force between the pair of left and right side rails. A second cross member (plate cross) for maintaining the distance between the side rails, wherein the first cross member is formed of the web in one of the pair of left and right side rails. A first member (first pipe member) fixed to the surface, a second member (second pipe member) fixed to the inner surface of the web in the other of the pair of left and right side rails, and the first member And a portion formed by fitting the second member, the fitting connecting the first member and the second member slidably to each other in the vehicle width direction and restricting relative displacement in the circumferential direction. And a portion.

That is, the cross member is fixed to the pair of left and right side rails, and the side rails are connected in the vehicle width direction to form a ladder-type chassis frame. The side rail extends in the vehicle front-rear direction. Each of the left and right side rails has a U-shaped cross section composed of the web and the flange. The web is a vertically oriented portion, and the flange is a portion extending from the upper and lower ends of the web toward the inside in the vehicle width direction.
Note that the cross-sectional shape of the first cross member may be a closed cross-sectional shape excluding a circular shape.

  According to a second aspect of the present invention, the cross member of the vehicle according to the present invention has at least one of the first member and the second member in the fitting portion in addition to the configuration according to the first aspect. It is characterized by comprising a flange portion or a folded portion at the end edge.

  At the edge of the first member and the second member on the outer fitting side, the flange portion or the folded portion is formed so as to protrude outward of the first cross member. On the other hand, at the end edge on the fitting side, the flange portion or the folded portion is formed so as to protrude inward of the first cross member. The flange portion means an end edge projecting outward or inward of the first cross member, and the folded portion is a bent end portion of the first cross member in the axial direction of the first cross member. It means the part extended. Both the flange portion and the folded portion have a shape protruding in the thickness direction of the first cross member.

According to a third aspect of the present invention, the cross member of the vehicle according to the present invention has a collar member (collar) in which the first member is inserted and fixed inside the closed cross-sectional structure. And the fitting portion is formed by fitting the collar member and the second member.
According to a fourth aspect of the present invention, the cross member of the vehicle according to the present invention includes the first member, the second member, and the inner surface of the web in addition to the configuration according to any one of the first to third aspects. The bracket further includes a bracket interposed in the fixing portion. The bracket is formed to be short in the vertical direction and long in the vehicle front-rear direction, and is fastened and fixed to an intermediate portion in the vertical direction on the inner surface of the web of the side rail. It is characterized by that.

According to a fifth aspect of the present invention, in the vehicle cross member of the present invention, in addition to the structure according to any one of the first to fourth aspects, the second cross member is erected substantially vertically so that the left and right It has the substantially flat plane part which connects between a pair of side rails, It is characterized by the above-mentioned.
According to a sixth aspect of the present invention, the cross member of the vehicle according to the present invention is characterized in that, in addition to the configuration of the fifth aspect, the second cross member is formed by perforating a plurality of holes in the flat portion. Yes.

According to a seventh aspect of the present invention, in the vehicle cross member of the present invention, in addition to the structure according to any one of the first to sixth aspects, the second cross member is provided in each of the pair of left and right side rails. It has the fixing | fixed part fixed in the position of two places up and down adjacent to the said flange of the said web inner surface.
According to a eighth aspect of the present invention, in the vehicle cross member according to the eighth aspect of the present invention, in addition to the structure according to any one of the first to seventh aspects, the chassis frame is disposed at intervals in the vehicle front-rear direction. The first cross member and the second cross member are applied to a No. 2 cross member located second from the front among the plurality of cross members. It is said.

  Note that, in a vehicle including a cab and a body, among the plurality of cross members disposed below the cab, the foremost one is the No. 1 cross member, and the plurality of cross members disposed below the body. The No. 2 cross member is the foremost cross member. The No. 2 cross member is a cross member disposed at a position closest to the front axle of the vehicle.

According to the cross member (Claim 1) of the vehicle of the present invention, among the deformations that can occur between the left and right side rails, the function of resisting torsion and the function of resisting tension are separated into separate members. Thereby, the structure of each member can be simplified.
That is, the first cross member only needs to have a shape capable of bearing a torsional torque that can be generated between the left and right side rails, and thus the closed cross-sectional shape can be reduced. On the other hand, the second cross member only needs to have a shape that can bear the tensile force in the vehicle width direction, and has only the strength necessary for maintaining the distance between the side rails, so that the cross section of the member can be reduced. . These also make it possible to reduce the weight and material costs of the entire chassis frame.

Moreover, according to the cross member (Claim 2) of the vehicle of the present invention, the rigidity of the end edge of each fitting portion can be increased, the effect of suppressing the twist by the first cross member can be increased, and the reliability can be improved. Can be increased.
Moreover, according to the cross member of the vehicle of the present invention (Claim 3), the cross-sectional shapes of the first member and the second member can be made the same by the connection through the collar member. Thereby, a cross member can be formed symmetrically, and the rigidity balance of a vehicle width direction can be ensured easily. Moreover, a single pipe can be divided into two parts, which can be used as a first member and a second member, respectively, and the configuration can be further simplified.

According to the cross member of the vehicle of the present invention (Claim 4), even if vertical bending deformation or torsional deformation occurs in the side rail, stress generated by the deformation is small in the intermediate portion of the side rail web. Therefore, the load acting on the fastener that fastens and fixes the bracket is mainly a shearing force, and the bracket, the fastener, the web, and the like are advantageous in strength.
Further, according to the cross member of the vehicle of the present invention (Claim 5), since the shape of the second cross member is substantially flat, both the processing cost and the weight can be reduced, and the space can be saved. Can be planned. Further, since the orientation of the second cross member is vertical, it is difficult to interfere with other devices arranged in and around the chassis frame, and the restrictions on the design of the vehicle layout can be reduced.

Moreover, according to the cross member of the vehicle of the present invention (Claim 6), the weight of the second cross member can be reduced by providing the hole in the plane portion.
Further, according to the cross member (Claim 7) of the vehicle of the present invention, the portion of the inner surface of the web adjacent to the flange has high rigidity and is difficult to be deformed in the vehicle width direction. By joining the two cross members, it is possible to suppress the generation of high stress due to the deformation of the mounting portion. In addition, since the stress generated by tension is greater in the vicinity of the upper and lower ends near the flange than in the intermediate portion of the web, the second cross member can be effectively resisted against tensile deformation.

  According to the vehicle cross member of the present invention (Claim 8), the first cross member and the second cross member are applied to the No. 2 cross member that is most likely to bear the torsional torque among the cross members of the chassis frame. Therefore, the effect of separating the function of resisting torsion between the left and right side rails and the function of resisting tension is high, and the chassis frame can be effectively protected from deformation.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
1 to 6 are views for explaining a cross member of a vehicle according to an embodiment of the present invention, and FIG. 1 is a schematic perspective view showing an entire configuration of a chassis frame to which the cross member is applied. 2 is a perspective view showing the overall configuration of the cross member, FIG. 3 is a cross-sectional view of a pipe cross (first cross member) in the cross member, and FIG. 4 is a front view of a bracket for the cross member.

5A and 5B are views showing a plate cross (second cross member) in the cross member, wherein FIG. 5A is a front view thereof, FIG. 5B is a top view thereof, and FIG. 6 is a chassis to which the cross member is applied. It is a schematic diagram for demonstrating the behavior of the twist of a flame | frame.
7A and 7B are cross-sectional views of a first cross member of a vehicle cross member as a modified example of the present invention, and similarly, FIGS. 8A and 8B are modified examples of the present invention. It is a perspective view of the 2nd cross member in the cross member of the vehicle as.

[1. Constitution]
[overall structure]
The cross member according to the present invention is applied to a ladder-type chassis frame 10 as shown in FIG. The chassis frame 10 includes a side rail 8 and a cross member 9.

  The side rails 8 are members that extend in the vehicle front-rear direction, and two side rails 8 are provided so as to form a pair on the left and right sides at a predetermined interval in the vehicle width direction. Each cross-sectional shape is formed in a U-shaped channel shape, and a flange 8b extends from the upper and lower ends of the vertically oriented web 8a toward the inside in the vehicle width direction. That is, the side rails 8 are arranged so that the inner surfaces of the webs 8a face each other.

The cross member 9 is a member that connects the left and right side rails 8 in the vehicle width direction, and is disposed at a plurality of locations at intervals in the vehicle front-rear direction. These cross members 9 are, in order from the front of the vehicle, No. 1 cross member 9a, No. 2 cross member 9b, No. 3 cross member 9c, No. 4 cross member 9d, No. 5 cross member 9e, and end cross member 9f. is called.
In the present embodiment, the cross members 9 are provided at six locations on the chassis frame 10, but the number of locations of the cross members 9 to be provided is generally the length of the wheel base (WB) and the type of the bodywork. It depends on (flat body, dump, tank truck, etc.).

As shown in FIG. 1, the No. 1 cross member 9a is the cross member 9 located at the front end of the chassis frame 10, and is a member to which the front bumper of the vehicle is fixed. On the other hand, the end cross member 9 f is located at the rear end of the chassis frame 10.
The No. 2 cross member 9b to the No. 5 cross member 9e are provided between the No. 1 cross member 9a and the end cross member 9f. These cross members 9b to 9e are located below the body behind the cab 13 of the vehicle, and the one closest to the adjacent portion between the cab 13 and the body is the No. 2 cross member 9b.

  As schematically shown in FIG. 1, the front axle 14 to which the front wheel 12 of the vehicle is pivotally attached is fixed to the side rail 8 between the No. 1 cross member 9a and the No. 2 cross member 9b. The rear axle 15 is fixed to the side rail 8 between the No. 4 cross member 9d and the No. 5 cross member 9e. In addition, since the vehicle running engine and the transmission are mounted between the No. 1 cross member 9a and the No. 2 cross member 9b, the distance between the cross members 9a and 9b is different from that of the other cross members 9b. It is larger than the adjacent interval. Further, the No. 2 cross member 9b is closest to the fixed position of the front axle 14, and is most susceptible to the torsional deformation of the chassis frame 10 during traveling.

  The cross member according to the present invention is applied as No. 2 cross member 9b. Hereinafter, the No. 2 cross member 9b is also simply referred to as a cross member 9b. As shown in FIG. 2, the cross member 9 b is configured by arranging a pipe cross (first cross member) 6 and a plate cross (second cross member) 7 in parallel.

[Pipe cloth]
The pipe cloth 6 is a pipe-like member that spans between the left and right side rails 8 in the vehicle width direction. The pipe cloth 6 bears a function of suppressing torsional deformation by bearing a torsional torque acting between the side rails 8. The torsional torque referred to here is a torsional moment in the rotational direction about an arbitrary axis extending in the vehicle width direction, and is generated by the torsion of the chassis frame 10.

  As shown in FIG. 2, the pipe cloth 6 is formed in a closed cross section over its entire length, and includes a first pipe member (first member) 1, a second pipe member (second member) 2, and a collar (color member). ) 3. The first pipe member 1 is fixed to the inner surface of the web 8 a in one of the left and right side rails 8, and the second pipe member 2 is fixed to the inner surface of the web 8 a in the other side rail 8. The first pipe member 1 and the second pipe member 2 are both oval cylindrical members having the same cross-sectional shape, and are arranged so that the ends face each other in the vicinity of the center in the vehicle width direction. As shown in FIG. 3, the length of each member is set so that the distance between the first pipe member 1 and the second pipe member 2 is d (d ≧ 0) in a state where the side rail 8 is not deformed. Is set.

  The first pipe member 1 and the second pipe member 2 are connected via a collar 3. The collar 3 is an elliptic cylindrical member having an outer peripheral surface having the same shape as the inner peripheral surfaces of the first pipe member 1 and the second pipe member 2. The collar 3 is inserted and fixed to the first pipe member 1. The fixing method is arbitrary, and for example, various fixing methods such as plug welding fixing and fastening fixing may be used.

On the other hand, the collar 3 is slidably inserted into the second pipe member 2. That is, the outer peripheral surface of the collar 3 is in sliding contact with the inner peripheral surface of the second pipe member 2. Hereinafter, the surface on which the collar 3 and the second pipe member 2 are fitted together is referred to as a contact surface 5a.
In addition, by connecting the first pipe member 1 and the second pipe member 2 with the collar 3, the elliptical cylinder axes of the first pipe member 1 and the second pipe member 2 are positioned on the same straight line. Hereinafter, both of these elliptical cylinder axes are referred to as axes C.

  Since the outer peripheral surface of the collar 3 has the same shape as the inner peripheral surface of the second pipe member 2 and does not restrict movement in the vehicle width direction, tensile force in the direction along the axis C is transmitted at the contact surface 5a. Not. Further, by making the contact surface 5a between the second pipe member 2 and the collar 3 into an elliptical cylinder shape, the relative displacement of the collar 3 in the circumferential direction of the second pipe member 2 is constrained and the rigidity works. That is, relative displacement between the first pipe member 1 and the second pipe member 2 is restricted, and a torsion torque about the axis C is transmitted between the first pipe member 1 and the second pipe member 2. The

  Thus, the pipe cloth 6 functions to suppress deformation in the torsional direction between the side rails 8, but has a structure that does not restrain movement in the vehicle width direction. In this embodiment, the contact surface 5a formed by fitting the collar 3 and the second pipe member 2 connects the first pipe member 1 and the second pipe member 2 to each other so as to be slidable in the vehicle width direction. It functions as a fitting portion 5 that regulates relative displacement in the circumferential direction.

The first pipe member 1 and the second pipe member 2 are each fixed to the inner surface of the web 8 a in the side rail 8 via the bracket 4. As shown in FIG. 4, the shape of the bracket 4 is short in the vertical direction and long in the vehicle front-rear direction. As shown in FIG. 2, the bracket 4 is fastened and fixed to an intermediate portion in the vertical direction on the inner surface of the web 8 a of the side rail 8. That is, the fastening position of the bracket 4 is near the center in the vertical direction of the web 8a as shown in FIG.
A fastener such as a bolt or a nut is used for fastening the bracket 4 to the web 8a.

[Plate cloth]
The plate cloth 7 is a thin plate-like member, and bears the function of restraining deformation in the vehicle width direction by bearing the tensile force between the left and right side rails 8 as an in-plane force. As shown in FIG. 5, the plate cloth 7 includes a flat plate-like flat portion 7 a and fixed portions 7 c that are bent at both right and left ends.

The flat surface portion 7 a is a portion that stands vertically and connects the left and right side rails 8 in the vehicle width direction, and is arranged in parallel with the pipe cloth 6. In this embodiment, in order to reduce the weight of the member, a plurality of hole portions 7b are perforated in the flat portion 7a to form a ladder shape. The fixing part 7c is a part for fixing the plate cloth 7 and the left and right side rails 8.
Two fixing portions 7c are provided at both the upper and lower ends of each of the left and right ends of the flat portion 7a, and these fixing portions 7c are fixed to the inner surface of the web 8a. Moreover, the position where the fixing | fixed part 7c is fixed is a position close to the flange 8b in the inner surface of the web 8a (near the corner where the web 8a and the flange 8b enter).

As described above, since the plate cloth 7 is formed in a thin plate shape, the left and right side rails 8 are allowed to be twisted and deformed, while the movement in the vehicle width direction is restricted to maintain the distance between the side rails 8. It is functioning.
Further, as shown in FIG. 2, the plate cloth 7 supports the pipe cloth 6 with fixtures attached to a plurality of locations on the flat surface portion 7a. In this embodiment, a U-bolt (U-shaped metal fitting) 11 is fastened to the flat portion 7a as a fixture, and the pipe cloth 6 is loosely mounted between the U-bolt 11 and the flat portion 7a. The U-bolt 11 is provided as a so-called steady rest, and is attached slightly loosely so as not to transmit torsional torque, tensile force, and compressive force between the pipe cloth 6 and the plate cloth 7.

  In addition, at the left and right ends of the plate cloth 7, concave portions 7d that are recessed inward in the vehicle width direction are formed at intermediate portions of the fixed portions 7c that are provided above and below. As shown in FIG. 2, the recess 7 d is for preventing interference between the flat portion 7 a and the bracket 4 in the arrangement state of the pipe cloth 6 and the plate cloth 7. In the present embodiment, since the bracket 4 is extended in the vehicle front-rear direction, the vertical middle portions of the left and right ends of the plate cloth 7 are notched inward, and the upper and lower fixing portions 7 c are provided so as to straddle the bracket 4. .

[2. Action]
[Action on torsional deformation]
When some load is input to the chassis frame 10, as shown in FIG. 6, a tensile force and a torsional torque in the vehicle width direction act on the cross member 9b. The cross member 9b functions to suppress deformation caused by these forces.

First, the plate cloth 7 is formed in a thin plate shape and does not attempt to resist torsional deformation. That is, the plate cloth 7 does not bear torsional torque.
On the other hand, in the pipe cloth 6, since the contact surface 5a between the second pipe member 2 and the collar 3 has an elliptical cylindrical shape, the relative displacement between the first pipe member 1 and the second pipe member 2 is restricted, and the rigidity is reduced. Will work. That is, the pipe cloth 6 tries to resist torsional deformation. Therefore, the torsion torque generated between the left and right side rails 8 is borne by the pipe cloth 6.

  Further, since the pipe cloth 6 is fixed to the intermediate portion in the vertical direction of the inner surface of the web 8a, the torsional torque borne here is applied to the pipe cloth 6 via a fastening bolt that fastens the web 8a and the bracket 4. Transmitted as shear force. That is, a vertical shearing force is applied to the bracket 4 and the fastening bolt interposed between the pipe cloth 6 and the web 8a.

[Action on tensile deformation]
In addition, the pipe cloth 6 does not attempt to resist deformation in the pulling direction because the outer peripheral surface of the collar 3 and the inner peripheral surface of the second pipe member 2 are slidable. That is, the pipe cloth 6 does not bear a tensile force. Further, no tensile force is applied to the bracket 4 interposed between the pipe cloth 6 and the web 8 a of the side rail 8.

On the other hand, in the plate cloth 7, since the tensile force related to such deformation is borne as the in-plane force of the flat surface portion 7a, the deformation is restricted. That is, the plate cloth 7 tries to resist deformation in the tensile direction. Therefore, the tensile force generated between the left and right side rails 8 is borne by the plate cloth 7.
In the vicinity of the No. 2 cross member 9b, an engine, a transmission, and the like are mounted between the left and right side rails 8 via mounting stays. Hardly works.

[3. effect]
As described above, in the cross member 9b of the present embodiment, among the deformations generated between the left and right side rails 8, the function of resisting torsion and the function of resisting tension are respectively represented by the pipe cloth 6 and the plate cloth. 7 and can be separated. That is, the pipe cloth 6 only needs to have a shape that can bear even a torsional torque, so that the closed cross-sectional shape (for example, the thickness or thickness of the member) can be reduced. Similarly, since the plate cloth 7 only needs to have a shape that can bear even the tensile force in the vehicle width direction, the cross-sectional shape can be reduced. Therefore, the structure of each member can be simplified, the weight and material cost of the cross member 9b can be reduced, and the weight and cost of the entire chassis frame 10 can be reduced.

  Further, with respect to the pipe cloth 6, since the first pipe member 1 and the second pipe member 2 have the same cross-sectional shape, the first pipe member 1 and the second pipe member 2 are divided into two elliptical pipes. The configuration is simple. Moreover, since it is the structure which connects them with the color | collar 3, it can implement | achieve easily the pipe structure which accept | permits a slide movement, resisting torsion.

  In the present embodiment, both the first pipe member 1 and the second pipe member 2 are fastened and fixed to the side rail 8 via the bracket 4, and the fastening position of the bracket 4 is the vertical direction of the web 8 a of the side rail 8. Near the center. Therefore, even if vertical bending deformation or torsional deformation occurs in the chassis frame 10, the compressive tensile stress in the vehicle width direction in the vicinity of the bracket 4 is small, and it is possible to design a cross member 9b that is advantageous in strength. Furthermore, as shown in FIG. 4, since the shape of the bracket 4 is a horizontally long shape extending in the vehicle front-rear direction, the load acting on the fastener that fastens and fixes the bracket 4 is mainly a vertical shearing force. Become. That is, since the shear load is small with respect to the torsional torque generated in the fastener, a design that is advantageous in terms of strength is possible, and downsizing is easy.

  Further, since the plate cloth 7 bears only in-plane force, it can be made thin. And by making it thin, both processing cost and weight can be reduced, and space saving can be achieved. Further, since the orientation of the plate cloth 7 is vertical, other devices arranged in and around the chassis frame 10 as compared with a cross member extending in the horizontal direction such as an alligator cloth, for example. It is possible to reduce the restrictions on the vehicle layout.

  Furthermore, since the fixing portion 7c of the plate cloth 7 is fixed in the vicinity of the upper and lower end portions having relatively high rigidity on the inner surface of the web 8a, even if a tensile force in the vehicle width direction is transmitted, it is difficult to be deformed and effectively. Stress can be transmitted. Moreover, generation of high stress due to such deformation can be prevented.

  Since the distance between the No. 1 cross member 9a and the No. 2 cross member 9b on which the engine, transmission, etc. are mounted is larger than the adjacent interval of the other cross members 9, the No. 2 cross member A twisting torque and a tensile force in the vehicle width direction are likely to be generated on the member 9b. Furthermore, since the No. 2 cross member 9b is disposed at the position closest to the fixed position of the front axle 14, the load is the largest among the other cross members 9, and it is difficult to reduce the size and weight accordingly. On the other hand, in this embodiment, by separating the distance maintaining function and the twist suppressing function of the No. 2 cross member 9b into two members, the structure of each member can be simplified, so that the size can be effectively reduced. And weight can be reduced.

  Thus, according to the cross member 9b, the weight of the entire chassis frame 10 can be reduced while ensuring the required rigidity and strength.

[4. Others]
Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit of the present invention.

  That is, the gist of the present invention is to appropriately set the rigidity and strength of each member by separating the member that bears the tensile force caused by the torsional deformation of the chassis frame 10 and the member that bears the torsional torque. This is to prevent the cross member 9 from having excessive performance as a whole. Accordingly, at least the first cross member that bears the torsional torque and the second cross member that bears the tensile force are provided, and the first cross member regulates the relative displacement in the circumferential direction by fitting the two members together. However, it may be anything that can be slid in the vehicle width direction. Various specific shapes of the first cross member and the second cross member are conceivable.

  For example, in the above-described embodiment, the first pipe member 1 and the second pipe member 2 of the pipe cloth 6 are connected via the collar 3, but the collar 3 is omitted as shown in FIG. It is good also as a structure. That is, the first pipe member 1 may be directly inserted into the second pipe member 2. In this case, on the contact surface 5a 'between the outer peripheral surface of the first pipe member 1 and the inner peripheral surface of the second pipe member 2, both are connected so as to be slidable in the vehicle width direction, and relative displacement in the circumferential direction is performed. Will be regulated. Even in such a configuration, the same effect can be obtained with a simpler configuration than the above-described embodiment.

  Moreover, in the above-mentioned embodiment, although the 1st pipe member 1, the 2nd pipe member 2, and the collar 3 of the pipe cross 6 are elliptical cylinder shape, cross-sectional shape is not limited to this. Except for a cylindrical shape (a cross-sectional shape is a circle), any columnar member such as a quadrangular prism (square) or a hexagonal column can be used, or those columnar members (including a cylindrical shape) It is also possible to use a material provided with groove-like irregularities.

  Further, as shown in FIG. 7 (a), the end of the first pipe member 1 may be bent radially inward to form the flange portion 1a, or the end of the second pipe member 2 may be formed. A similar flange portion 2a may be provided on the edge so as to face radially outward. By increasing the rigidity of the end edge in the fitting portion 5, it is possible to increase the twist suppression effect by the pipe cloth 6. Further, by reinforcing the end edge, the member life can be extended, and the reliability can be continuously increased.

Alternatively, as shown in FIG. 7B, folded portions 1b and 2b may be formed instead of the flange portions 1a and 2a. That is, by folding back the end edge of the pipe cloth 6, the rigidity of the outer fitting side end edge and the fitting side end edge of the fitting portion 5 can be improved.
In the above-described embodiment, the thin plate-like plate cloth 7 is used as the member that bears the tensile force between the left and right side rails 8, but the member shape is not limited to this. It is sufficient if it can bear at least the tensile force between the left and right side rails 8. For example, as shown in FIG. The two cross members 7 'may be configured, or the second cross member 7 "may be configured using an angle member (L-shaped steel) as shown in FIG. In addition, the number of the angle members and the direction of the arrangement can be set as appropriate.

  In the above-described embodiment, the bracket 4 has a shape that is short in the vertical direction and long in the vehicle front-rear direction. This is due to the stress generated between the first pipe member 1 or the second pipe member 2 and the web 8a. It can be appropriately changed according to the size and the like. Note that a fixing method such as welding fixing may be used instead of the fixing by the fastener. Alternatively, the end portions of the first pipe member 1 and the second pipe member 2 may be directly fixed to the side rail 8 without using the bracket 4.

In the above-described embodiment, the cross member according to the present invention is applied as the No. 2 cross member 9b. However, it is of course possible to apply it as the other cross member 9.
The chassis frame 10 to which the cross member according to the present invention is applied can be applied to various vehicles such as trucks such as dump trucks and van type cars, tank trucks, large / medium-sized buses, special vehicles, and freight vehicles. .

1 is a schematic perspective view showing an overall configuration of a chassis frame to which a cross member of a vehicle according to an embodiment of the present invention is applied. 1 is a perspective view showing an overall configuration of a cross member of a vehicle according to an embodiment of the present invention. It is sectional drawing of the 1st cross member (pipe cross) in the cross member of the vehicle which concerns on one Embodiment of this invention. It is a front view of the bracket for cross members of the vehicle concerning one embodiment of the present invention. It is a figure which shows the 2nd cross member (plate cross) in the cross member of the vehicle which concerns on one Embodiment of this invention, (a) is the front view, (b) is the top view. It is a mimetic diagram for explaining the twisting behavior of the chassis frame to which the cross member of the vehicle concerning one embodiment of the present invention is applied. It is sectional drawing of the 1st cross member in the cross member of the vehicle as a modification of this invention, (a) is provided with the flange part, (b) is provided with the folding | turning part. It is a perspective view of the 2nd cross member in the cross member of the vehicle as a modification of this invention, (a) uses a round bar, (b) uses an angle material.

Explanation of symbols

1 First pipe member (first member)
1a Flange part 2 Second pipe member (second member)
2a Flange 3 Color (Color material)
4 Bracket 5 Fitting 6 Pipe cross (first cross member)
7 Plate cloth (second cross member)
7a Plane portion 7b Hole portion 7c Fixed portion 8 Side rail 8a Web 8b Flange 9 Cross member 9b No.2 cross member 10 Chassis frame

Claims (8)

Fixed to a pair of left and right side rails each having a U-shaped cross section with flanges extending in the longitudinal direction of the vehicle and extending from the upper and lower ends of the vertically oriented web toward the inner side in the vehicle width direction. A cross member of a vehicle that forms a ladder-type chassis frame by connecting the side rails in the vehicle width direction,
A first cross member having a closed cross-sectional structure that bears a torsion torque between the pair of left and right side rails and suppresses the torsion of the side rails;
A second cross member that bears the tensile force between the pair of left and right side rails and maintains the distance between the side rails;
The first cross member is
A first member fixed to the inner surface of the web in one of the pair of left and right side rails;
A second member fixed to the inner surface of the web in the other of the pair of left and right side rails;
A portion formed by fitting the first member and the second member, wherein the first member and the second member are slidably connected to each other in the vehicle width direction, and are displaced relative to each other in the circumferential direction. A vehicle cross member comprising: a fitting portion that regulates the fitting member. 2. The vehicle cross member according to claim 1, wherein at least one of the first member and the second member in the fitting portion includes a flange portion or a folded portion at an end edge thereof. . The first member has a collar member inserted and fixed inside the closed cross-sectional structure,
3. The vehicle cross member according to claim 1, wherein the fitting portion is formed by fitting the collar member and the second member. A bracket interposed between the first member and the second member and the inner surface of the web;
The bracket according to claim 1, wherein the bracket is short in the vertical direction and long in the vehicle front-rear direction, and is fastened and fixed to an intermediate portion in the vertical direction on the inner surface of the web of the side rail. The cross member of the vehicle according to any one of the preceding claims. The said 2nd cross member has a substantially flat plane part which stands up substantially perpendicularly and connects between the said left-right paired side rail, The any one of Claims 1-4 characterized by the above-mentioned. The cross member of the vehicle according to the item. 6. The vehicle cross member according to claim 5, wherein the second cross member has a plurality of holes formed in the flat portion. The said 2nd cross member has the fixing | fixed part fixed in the position of two upper and lower positions adjacent to the said flange of the said web inner surface in each of said left-right paired side rail. The vehicle cross member according to any one of? 6. The chassis frame includes a plurality of cross members disposed at intervals in the vehicle front-rear direction,
The first cross member and the second cross member are applied to a No. 2 cross member located second from the front among the plurality of cross members. The cross member of the vehicle according to any one of the preceding claims.

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