JPH0655950U - Vehicle ladder frame - Google Patents

Abstract

(57) [Abstract] [Purpose] In a ladder frame of a vehicle consisting of a combination of two side rails and several cross members, a bent portion of the cross member that is connected to the web surface of the side rail (both ends are L-shaped). It is effectively prevented from cracking from both ends to form a fastening surface with the web surface). [Structure] Both ends of a cross member 1 are bent into an L shape to form a fastening surface 3 for a web surface 2a of a side rail 2, and bent portions 4 are formed on both sides of the fastening surface 3.
A plurality of bent shape portions 5 are provided in the widthwise direction before and after the.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 This invention relates to a ladder frame of a vehicle.

[0002]

[Prior art]

 Conventionally, the most common type of truck frame is a ladder type, which is a combination of two side rails and several cross members. As such a frame, there is known a frame in which both ends of a cross member are bent inwardly in an L shape to form a fastening surface, and the fastening surface is joined to the web surface of the side rail by rivets or bolts ( (Application No. Sho 63-155950).

However, in such a conventional example, when the frame is deformed by an external force, a high stress is generated on the fastening surface of the cross member, in particular, the bent portion thereof, and both ends (edges) in the plate width direction extend along the bent portion. There was a problem that cracks tended to occur. For this reason, there are some cases where a reinforcing material is attached to the back side of the bent portion, but this is disadvantageous in terms of manufacturing cost.

[0006] Therefore, there has been proposed a cross member upper gazette in which reinforcing webs that are bent inward are formed on both sides of the web fastening surface so as to bend to the bent portions (Japanese Utility Model Laid-Open No. 4-51871).

[0005]

[Problems to be solved by the device]

 However, in that case, the rib bends in an L-shape so as to extend the bent portion of the fastening surface when viewed from the side, so that the stress concentration due to the deformation of the frame causes cracks from the bent end surface (edge), When it crossed the rib and reached the fastening surface, there was a possibility that it would proceed at a stretch along the bent portion. In other words, the rib alone exerts a high stress on the bent end surface, so that there is a problem that cracks on both sides of the fastening surface cannot be sufficiently prevented.

An object of the present invention is to effectively prevent the occurrence of cracks at the web fastening surface of the cross member, especially at both ends of the bent portion thereof by a simple countermeasure.

[0007]

[Means for Solving the Problems]

 Therefore, in this invention, in a ladder frame of a vehicle including a combination of two side rails and several cross members, both end portions of the cross members are bent into L-shapes, and the fastening surface to the web surface of the side rails. In addition to forming the ridges, several folds are formed in the lateral width direction on both sides of these fastening surfaces in front of and behind the folds.

[0008]

[Action]

 As the frame is deformed, a high stress is generated on the web fastening surface of the cross member, especially on the bent part.However, the stress is suppressed at these bend lines due to the bending shape of several steps, and Since the outer end surface (edge) is not reached, as a result, it is possible to effectively prevent cracking from both ends in the bent portion forming the web fastening surface of the cross member.

[0009]

【Example】

 1 and 2 show an example of application to a channel-type cross member 1 (composition member of a ladder-type frame), in which both ends of the web of the side rail 2 are bent inward in an L-shape. A fastening surface 3 for the surface 2a is formed. Reinforcing edges 5 (fold-shaped portions) are provided on the fastening surface 3 by bending the both sides forward and backward of the bent portion 4 in two steps toward the back and the outside. Then, the cross member 1 abuts the fastening surfaces 3 at both ends against the web surface 2a of the side rail 2 and is joined by rivets or bolts.

With such a structure, when the ladder frame is deformed by an external force, a high stress is generated on the web fastening surface 3 of the cross member 1, particularly the bent portion 4, but the stress is a two-fold bent shape 5. Therefore, the bending line portions are suppressed and do not reach the outer end surface 5a (edge) of the bending shape portion 5. In other words, since the outer end surface 5a is separated from the high stress working range, it is possible to effectively prevent the bent portion 4 of the cross member 1 from cracking from both ends as a result. The fastening surface 3 of the cross member 1 may be bent as shown in FIG.

FIG. 4 shows an example of application to the arugator type cross member 6. The upper and lower ends of the aggregator type cross member 6 are bent in the same direction in an L-shape to fasten the side rail 2 to the web surface 2a. A surface 7 is formed, and a two-fold bent shape portion 9 is provided from both sides of the fastening surface 7 to the bent portion 8.

The cross member 9 has the fastening surfaces 8 at both ends abutted against the web surface 2a of the side rail 2 and is joined by a rivet or a bolt. In this example, the cross member 9 is also generated due to the deformation of the frame. Since the stress stops at these bending line portions due to the two-fold bent shape and does not reach the outer end surface 9a (edge) of the bent shape portion 9, it is possible to effectively prevent cracks from entering the bent portion 8 from both ends.

FIGS. 5 and 6 show an application example in which the cross member 10 has the gusset 12 forming the web fastening surface 11 for the side rail 2, and the upper gusset 12 a and the lower gusset 12 b respectively have tips. By bending the sides in the same direction to form an L-shape, fastening surfaces 11 for the web surface 2a of the side rail 2 are formed, and from both sides of these fastening surfaces 11 to the bent portion 13, the end face 14a (edge) has a turtle. A two-stage bent shape portion 14 that prevents the occurrence of cracks is provided.

In this case, the fastening surface 11 of the upper gusset 12a and the lower gusset 12b may be bent as shown in FIG. 7, and the entire gusset 12 including the fastening surface 11 as shown in FIG. It may be formed in.

The bent shapes 5, 9 and 14 are the bent portions 4 to the fastening surfaces 3, 7 and 11 as shown in FIG. 9 in any of the application examples to the channel type, the arugator type and the gusset. , 8 and 13 may be used, and the cross-sectional shape as shown in FIG.

[0016]

[Effect of device]

 In summary, according to the present invention, in a ladder frame of a vehicle including a combination of two side rails and several cross members, both ends of the cross members are bent into L-shapes to tighten the side rails against the web surface. Along with forming the attachment surface, several steps of bending shape were provided in the lateral width direction on both sides of these fastening surfaces before and after the bending part, so that the stress generated due to the deformation of the frame is due to the two-step bending shape. Since it does not extend to the outer edge (edge) of the bent shape, it is possible to effectively prevent cracks from entering from both ends in the bent portion, and it is possible to obtain the effect of improving frame durability.

[Brief description of drawings]

FIG. 1 is a partial perspective view of a channel type cross member.

FIG. 2 is a fastening state diagram of the same with a side rail.

FIG. 3 is an explanatory view illustrating a method of bending the web fastening surface.

FIG. 4 is a partial perspective view of an alligator-type cross member.

FIG. 5 is a front view of a cross member with a gusset.

FIG. 6 is a perspective view of the same gusset.

FIG. 7 is an explanatory view illustrating the method of bending the gusset as well.

FIG. 8 is an explanatory view showing a modified example of the gusset.

FIG. 9 is an explanatory diagram illustrating a modification of a bent shape.

FIG. 10 is an explanatory view illustrating a modification of the bent shape.

[Explanation of symbols]

 1,6,10 Cross member 2 Side rail 2a Side rail Web surface 3,7,11 Fastening surface 4,8,13 Bending part 5,9,14 Bending shape part

Claims (1)

[Scope of utility model registration request] 1. A ladder frame for a vehicle comprising a combination of two side rails and several cross members, wherein both ends of the cross members are bent in an L shape so that a fastening surface of the side rails with respect to a web surface is fastened. As it forms
A ladder frame for a vehicle, characterized in that a folded shape portion having several steps in the lateral width direction is provided on both sides of these fastening surfaces before and after the bent portion.