JP2002046538A - Mounting structure for step - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a mounting structure for a step minimizing fracture damage in a collision. SOLUTION: In this mounting structure for the step, a plurality of pot bottom shaped mounting depressions 24 are formed in a face 22 of a step 2 rear part in parallel with a vehicular fore and aft direction. It has a mounting bolt hole 25 formed from a mounting bolt insertion hole part 24c with a diameter slightly larger than a diameter of a screw part of a mounting bolt 6 formed in a bottom part 24a of the mounting depression 24, a slit 24d passing a center of this bolt insertion hole part 24c, continuous with this bolt insertion hole part 24c and formed toward a vehicular front, and a drop hole 24e continuous with a front of this slit 24d and formed in a cylindrical part 24b of the mounting depression 24 with a size allowing passage of a head part of the mounting bolt 6.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mounting structure of a step for getting on and off a truck including a step hanger front, a step hanger rear, a step and a mounting bolt.

[0002]

2. Description of the Related Art FIG. 3 is a part of a side view of a truck, 8 is a cab, 7 is a front bumper, and 2 is a step. FIG. 2 is a diagram showing a configuration around the step and an attached state.

In FIG. 2, a step hanger front 1 is fastened to the front end of the left frame 5 by bolts or rivets. Step hanger front 1
A step hanger rear 3 is fixed to the frame 5 by bolts or rivets with a certain distance behind. The front part of the step is attached to the step hanger front 1 and the rear part is attached to the step hanger rear 3 and bolts 6. In the figure, 9 is a front cross member, 11 is a step hanger front 1
4 indicates mud from the front wheel to the headlamp side, mudguard to prevent water from scattering,
Reference numeral 21 denotes a step portion of Step 2, 22 denotes a step cover portion, 23 denotes a front mounting hole, and 25 denotes a rear mounting hole.

In the prior art, this mounting state is such that the mounting hole on the step 2 side is 0.5 mm to 1.
The structure was such that it could be firmly attached with a 0 mm large hole.
However, according to this mechanism, when the step hanger front 1 is deformed due to a collision, the step 2 is pushed backward as shown in FIG. 25, and the step hanger rear 3 firmly attached thereto is also deformed. There was a problem to say that. In FIG. 25, F is the impact force due to the collision, 1
Reference numerals a and 1a denote deformations generated on the step hanger front 1, and reference numerals 3a and 3a denote deformations generated on the step hanger rear 3.

[0005]

SUMMARY OF THE INVENTION The present invention has been made in view of the above, and an object of the present invention is to provide a mounting structure of a step for minimizing damage and damage at the time of collision.

[0006]

In order to achieve the above object, according to the present invention, in a step including a step hanger front, a step hanger rear, a step and a mounting bolt, a front portion of the step is connected to a side end of the step hanger front. The rear part of the step is a step mounting structure that is mounted to the side end of the step hanger rear with mounting bolts, and is configured such that the step comes off the step hanger rear when an impact is applied to the step hanger front side. .

A plurality of pot-shaped recesses are formed in a plane parallel to the front-rear direction of the vehicle at the rear of the step, and a mounting bolt insertion hole having a diameter slightly larger than the diameter of the screw portion of the mounting bolt formed at the bottom of the recess. And a slit passing through the center of the bolt insertion hole and connected to the bolt insertion hole and formed toward the front of the vehicle; and a slit connected to the front of the slit and formed in the cylindrical portion of the recess, and a head of the mounting bolt. It has a mounting bolt hole formed by a bolt relief hole large enough to allow the part to pass through.

In the step including the step hanger front, the step hanger rear, the step and the mounting bolt, the front part of the step is a side end of the step hanger front, and the rear part of the step is a side end of the step hanger rear by the mounting bolt. A step mounting structure to be mounted, wherein when an impact is applied to the front side of the step hanger, a fragile portion is provided around the mounting hole at the rear of the step, and the fragile portion is broken by an impact force.

A plurality of pot-bottom recesses are formed in a plane parallel to the front-rear direction of the vehicle at the rear of the step, and mounting holes are formed in the bottoms of the recesses. A plurality of holes for reducing the impact strength are provided in a row.

A plurality of pot-bottom recesses are formed in a plane parallel to the front-rear direction of the vehicle at the rear of the step, and mounting holes are formed in the bottoms of the recesses. A plurality of points for reducing impact strength are provided in a row.

A plurality of pot-bottom recesses are formed in a plane parallel to the front-rear direction of the vehicle at the rear of the step, and mounting holes are formed in the bottoms of the recesses. Notches are provided to reduce impact strength.

A groove is formed all around the notch.

According to the step mounting structure of the present invention,
Even if the impact load due to the collision acts on the step hanger front and the step is pushed backward, the mounting bolt at the rear of the step falls out of the escape hole connected to the bolt insertion hole through the slit, so the step hanger rear or There is no possibility of damaging mudguard etc. That is, damage can be minimized.

[0014]

Embodiments of the present invention will be described below with reference to the drawings. Since the configuration around the step is the same as that of the conventional technology, the description of the overlapping part is omitted.

FIGS. 1, 4 and 5 show a first embodiment of the present invention and are three-dimensional views of a step mounting portion in FIG. Referring also to FIG. 2, a recess 24 for attaching to the step hanger rear 3 is provided at a rear portion of the step cover portion 22.

As shown in FIG. 4 (front view) and FIG. 5, which is a view taken in the direction of the arrow in FIG. 4, the step mounting recess 24 has a pot-shaped bottom cross-section and comprises a bottom 24a and a cylindrical portion 24b, and the center of the bottom 24a. The mounting bolt 6 includes a mounting bolt insertion hole 24c having a diameter Db slightly larger than the diameter D of the threaded portion of the mounting bolt 6, and the center of the bolt insertion hole 24c.
a slit 2 connected to the front of the vehicle and formed toward the front of the vehicle
The mounting bolt hole 25 is formed by a bolt relief hole 24e which is formed in the cylindrical portion 24b, and which is formed in the cylindrical portion 24b and which can pass through the head of the mounting bolt.

Here, the diameter Db of the slightly larger diameter mounting bolt insertion hole is D + 0.5 m if the diameter of the bolt is D.
Generally, it is set to m to D + 1 mm. Further, the width L of the slit portion 24d is desirably 0.8D ≦ L ≦ 0.9D.

Next, a mechanism in which the mounting bolts fall off (fall out) from the step 2 when an impact load of F is received from the front due to a collision with the step hanger front 1 will be described with reference to FIGS. . FIG. 6 is a state diagram before the collision, and FIG. 7 is a sectional view of FIG.

FIG. 8 is a state diagram of the collision process, and FIG. 9 is a sectional view of FIG. At the time of the collision, an impact load of F acts on the step 2, and the position of the slit 24 d has moved to the position of the mounting bolt 6. At this time, the width L of the slit 24d, which was smaller than the diameter of the bolt 6 before the collision, is crushed and expanded.

FIG. 10 is a view showing a state in which the collision proceeds further and immediately before the collision is completed, and FIG. 11 is a sectional view of FIG. As the collision progresses, step 2 moves to the right in the drawing, and the bolt relief hole 24e passes through the head of the bolt 6, and then step 2 is completed by separating from the step hanger rear 3 to which the mounting bolt 6 is fixed. I do. That is, FIG.
In the state before the collision shown in FIG. 2, as shown in FIG. 13, the step hanger front 1 deforms 1 a and 1 a after the collision, but the bolt is disengaged from the step 2 at the rear mounting portion (mounting recess) 24. After the step hanger rear 3, there is no influence such as deformation.

Next, as a second embodiment, FIG. 14 shows an example in which a plurality of holes 24f (shear holes) for reducing impact strength are provided in a row at equal pitches on the entire circumference of the cylindrical portion 24b of the mounting recess. 15 (transverse sectional view of FIG. 14). In FIG. 14, when the impact force F due to the collision acts on the step 2, as shown in FIGS. 16 and 17 (transverse sectional view of FIG. 16), the cylinders 24b of the mounting recess 24 are provided in a line at an equal pitch. All of the plurality of holes (shear holes) 24f are sheared so as to be connected, and the step 2 and the step hanger rear 3 are separated, so that the step hanger rear 3 does not deform.

Next, as a third embodiment, an example in which a plurality of points 24g for reducing impact strength are provided in a line at equal pitches on the entire circumference of the cylindrical portion 24b of the mounting recess is shown in FIGS.
9 (transverse sectional view of FIG. 18). The result when the impact force F due to the impact acts on the step 2 is the same as that of the second embodiment (FIGS. 14 to 17). (Several points 24g provided in a row are sheared so as to be connected. )), So the explanation is omitted.

Next, as a fourth embodiment, an example in which a notch 24h for reducing impact strength is provided over the entire circumference of the cylindrical portion of the mounting recess is shown in FIGS. 20 and 21 (XX in FIG. 20).
(Cross-sectional view). In FIG. 20, the impact force F due to the collision is shown.
Acts on the step 2, shear fracture occurs from the weakest cross-sectional position of the notch 24h and the step hanger rear 3 is separated from the step hanger rear 3 so that the step hanger rear 3 is not deformed.

Next, as a fifth embodiment, there is shown a structure (an enlarged view) in which notches 24h provided over the entire circumference of the aforementioned cylindrical portion 24b are provided with shear grooves 24j over the entire circumference at equal intervals. 22. This is one that is more easily sheared than the fourth embodiment.

Next, as a sixth embodiment, an example in which a shearing groove 24j for reducing impact strength is provided at equal intervals over the entire circumference of the cylindrical portion 24b of the mounting recess is shown in FIG. FIG. 24 (an example of a groove elongated in the depth direction of the cylindrical portion). The mechanism leading to the fracture is basically the same as that of the second embodiment, and therefore the description is omitted.

[0026]

The effects of the present invention will be described below. (1) Only the step falls off in response to an impact from the front including the step collision, so that damage to components in other steps can be prevented. (2) It is possible to prevent the units attached to the step hanger rear from being damaged. (3) Since there is no contact with the tire due to damage after the step hanger rear, provisional running after the accident is possible.

[Brief description of the drawings]

FIG. 1 is a three-dimensional view of a step mounting portion according to a first embodiment of the present invention.

FIG. 2 is a configuration diagram around a step.

FIG. 3 is a side view of a front portion of a truck including a cab.

FIG. 4 is a front view of a step mounting recess according to the first embodiment of the present invention.

FIG. 5 is a view taken in the direction of arrows in FIG. 4;

FIG. 6 is a view showing a mechanism of detachment of a mounting bolt from a step in the first embodiment of the present invention. (State diagram before collision)

FIG. 7 is a sectional view of FIG. 6;

FIG. 8 is a view showing a mechanism of detachment of a mounting bolt from a step in the first embodiment of the present invention. (State diagram of the collision process)

FIG. 9 is a sectional view of FIG. 8;

FIG. 10 is a view showing a mechanism of detachment of a mounting bolt from a step in the first embodiment of the present invention. (State diagram immediately before completion of collision)

11 is a sectional view of FIG.

FIG. 12 is a state diagram around a step during a collision according to an embodiment of the present invention. (Before collision)

FIG. 13 is a state diagram around a step at the time of a collision according to the embodiment of the present invention. (After collision)

FIG. 14 is a three-dimensional view of a structure in which a plurality of shearing holes are provided in a row in a cylindrical portion of a mounting recess according to a second embodiment of the present invention.

FIG. 15 is a sectional view of FIG. 14;

FIG. 16 is a view showing a state where shearing is performed from a shearing hole by collision with respect to FIG. 14;

FIG. 17 is a sectional view of FIG. 16;

FIG. 18 is a three-dimensional view of a structure according to a third embodiment of the present invention, in which a plurality of points (indentations) are provided in a line on a cylindrical portion of a mounting recess.

FIG. 19 is a sectional view of FIG. 18;

FIG. 20 is a three-dimensional view of a structure in which a continuous notch is provided all around the cylindrical portion of the mounting recess according to the fourth embodiment of the present invention.

FIG. 21 is a sectional view taken along line XX of FIG. 21;

FIG. 22 is a partially enlarged view of a structure of a fifth embodiment of the present invention, in which grooves are provided at equal intervals in a notch in the fourth embodiment.

FIG. 23 is a three-dimensional view of a structure according to a sixth embodiment of the present invention, in which a long groove is provided in the circumferential direction over the entire circumference of the cylindrical portion of the mounting recess.

FIG. 24 is a three-dimensional view of a structure in which a longitudinal groove is provided in the depth direction all around the cylindrical portion of the mounting recess according to the sixth embodiment of the present invention.

FIG. 25 is a diagram showing a deformation of a step hanger caused by a collision in the related art.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Step hanger front 2 ... Step 3 ... Step hanger rear 5 ... Frame 6 ... Bolt 21 ... Step part 24 ... Mounting recess 24a ... Bottom part 24b ...・ Cylindrical part 24c ・ ・ ・ Bolt insertion part 24d ・ ・ ・ Slit part 24e ・ ・ ・ Bolt relief hole 24f ・ ・ ・ Shear hole 24g ・ ・ ・ Point 24h ・ ・ ・ Notch 24j ・ ・ ・ Shear groove

Claims (8)

[Claims] 1. A step including a step hanger front, a step hanger rear, a step, and a mounting bolt, wherein the front of the step is attached to a side end of the step hanger front, and the rear of the step is attached to a side end of the step hanger rear. A step mounting structure mounted by bolts, wherein the step is detached from the step hanger rear when an impact is applied to the step hanger front side. 2. A plurality of pot-bottom mounting recesses are formed in a plane parallel to the front-rear direction of the vehicle at the rear of the step, and the diameter of the screw portion of the mounting bolt formed at the bottom of the mounting recess is slightly larger than the diameter of the screw portion. A bolt insertion hole having a diameter, a slit passing through the center of the bolt insertion hole and connected to the bolt insertion hole and formed toward the front of the vehicle, and a cylinder connected to the front of the slit and having a cylindrical portion of the mounting recess. The step mounting structure according to claim 1, further comprising a mounting bolt hole formed and formed by a bolt escape hole having a size that allows a head of the mounting bolt to pass therethrough. 3. A step including a step hanger front, a step hanger rear, a step, and a mounting bolt, wherein a front portion of the step is attached to a side end of the step hanger front and a rear portion of the step is attached to a side end of the step hanger rear. A step mounting structure mounted by bolts, wherein when an impact is applied to the front side of the step hanger, a fragile portion is provided around a mounting hole at a rear portion of the step, and the fragile portion is broken by an impact force. Step mounting structure. 4. A plurality of pot-bottom mounting recesses are formed in a plane parallel to the front-rear direction of the vehicle at the rear of the step, and holes for mounting bolts are formed in the bottoms of the mounting recesses. 4. A plurality of holes for reducing impact strength are provided in a row on the entire circumference of the cylindrical portion.
Mounting structure for the described steps. 5. A plurality of pot-bottom mounting recesses are formed in a plane parallel to the front-rear direction of the vehicle at the rear of the step, and holes for mounting bolts are formed at the bottom of the mounting recesses. A plurality of points for reducing impact strength are provided in a row on the entire circumference of the cylindrical portion.
Mounting structure for the described steps. 6. A plurality of pan-bottom mounting holes are formed in a plane parallel to the front-rear direction of the vehicle at the rear of the step, and holes for mounting bolts are formed at the bottom of the mounting holes. 4. The step mounting structure according to claim 3, wherein a notch is provided on the cylindrical portion to reduce impact strength over the entire circumference. 7. The step mounting structure according to claim 6, wherein the notch has a groove formed over the entire circumference of the cylindrical portion. 8. A plurality of pot-bottom mounting recesses are formed in a plane parallel to the front-rear direction of the vehicle at the rear of the step, and holes for mounting bolts are formed at the bottom of the mounting recesses. 4. The step mounting structure according to claim 3, wherein a plurality of grooves for reducing impact strength are provided on the entire cylindrical portion.