JPS5844490B2 - dump truck - Google Patents

Description

[Detailed description of the invention] The present invention relates to a dump truck.

In conventional dump trucks, a subframe is mounted on the chassis frame, a support shaft is inserted through the rear end of the subframe, and a hinge bracket that protrudes downward from the longitudinal girder on the bottom surface of the deck of the loading box is attached to the support shaft. The cargo box was attached to the subframe so that it could tilt freely around the support axis.

By the way, when loading earth and sand into a dump truck,
There is a desire to lower the height of the center of gravity above the ground as much as possible to improve driving stability during cornering and the like.

Therefore, if the deck of the cargo box is lowered and the height of the subframe is made smaller in order to lower the height of the center of gravity above the ground while maintaining the conventional structure described above, it is possible to reduce the height of the subframe by lowering the height of the subframe. In addition to the frame becoming unable to withstand the load, when the load is tilted to near the maximum angle, the rear lower end of the cargo box and the lower end of the tailgate become embedded in the discharged soil that is piled up on the ground, and the undischarged dirt that remains inside the cargo box becomes embedded. There was a problem in that the earth and sand could not be completely discharged unless the dump truck was moved forward, and the earth and sand discharge performance of the dump truck deteriorated.

The present invention has been made in view of these points,
In addition to lowering the height of the cargo box deck above the ground to improve driving performance, it also maintains a large ground height at the rear lower end of the cargo box and the lower end of the tailgate when the cargo box is tilted to the maximum angle, improving soil discharge performance. The present invention is characterized in that a recess is formed by cutting out the upper corners of the rear ends of the left and right vertical frames of the chassis frame, and a cross member is formed to bridge the left and right vertical frames. The left and right ends of the cross member are welded and fixed in the recess, and a hinge bracket is fixed to the upper protrusion of the cross member, and a support shaft pivoted to the upper top of the hinge bracket penetrates the longitudinal beam of the cargo box. It is considered as an insert,
The cargo box is attached to the chassis frame so as to be tiltable about the support shaft.

The present invention will be explained in detail below based on the illustrated embodiments.

In Fig. 1, 1 is a dump truck, 2 is a chassis, and 3 is a dump truck.
is a front wheel, 4 is a rear wheel, and a cargo box 6 is mounted on a chassis frame 5 of this chassis 2.

Further, the chassis frame 5 has a pair of left and right vertical frames 7.7 as shown in FIG.
... is provided to form a ladder shape or the like, and furthermore, the cross-sectional shape of the vertical frame 7 is box-shaped by combining two U-shaped members as shown in FIG. A spacer frame 9 having a height dimension B smaller than the width dimension A of this cross section is attached along the upper surface of the vertical frame 7 as shown in FIGS. An abutment timber 10 is attached to the abutment timber 10, and the lower surface 12 of the longitudinal beam 11 of the packing box 6 shown in FIGS. 3 and 4 abuts against this abutment timber 10 in a resting manner during traveling.

Note that the height dimension B of the spacer frame 9 is equal to the above-mentioned dimension A.
The following may be sufficient, and depending on the case, the spacer frame 9 may be made into a strip-like shape, or may be omitted altogether.

Therefore, in FIG. 1, a multi-stage telescopic cylinder 15 is used as the dump mechanism 13, and this cylinder 15 is arranged in front of the front wall 14 of the cargo box 6. The chassis frame 5 is pivotally connected to the front position of the chassis frame 5 by shafts 16 and 17.

Reference numeral 18 denotes a support shaft to which the rear part of the cargo box 6 is directly pivotally connected to the chassis frame 5 so that the rear part of the cargo box 6 can be tilted and dumped. A cylindrical boss 20 is fixed to a pair of left and right box-shaped vertical beams 11 connected to each other, and the support shaft 18 is fitted into the hole 21 of the cylindrical boss 20 in a penetrating manner. Free to move.

As shown in FIGS. 2, 3 and 4, approximately rectangular recesses 22.degree. is,
The cross member 23 is fitted into this recess 22.22, and the left and right ends 24.24 of the cross member 23 are fitted into this recess 22.
By welding at 22, the left and right ends 24.24 of the cross member 23 are fixedly integrated with the vertical frame 7.7.

In this way, the pair of left and right vertical frames 7.7 are bridged.

A hinge bracket 26.26 is fixed to the cross member 23 in an upwardly projecting manner, and extends in parallel to the outer and inner surfaces of the longitudinal beam 11 to both the outer and inner openings of the hole 21.

The upper apex 27.27 of this hinge bracket 26.26
The support shaft 18 is inserted into the holes 28, 28,
Specifically, two hinge brackets 26 are provided on each of the left and right vertical beams It and 11 of the cargo box 6, and the support shaft 18 is inserted into the holes 28, 21, and 28 in a skewer-like manner. inserted,
It is supported as a double-sided beam.

Specifically, as shown in FIGS. 5 and 6, the cross member 23 has an L-shaped member 29 and a 7-shaped member 30 in cross section.
Together, it has a rectangular box shape and has a rear extending part 31 whose lower side extends rearward, and as shown in FIG. The cross member 23 is in contact with.

Additionally, a cover plate 3 is provided on both end surfaces 32 and 32 of the cross member 23.
3 is fixed in a lid-like manner, and both end surfaces 32.32
protrudes outward by a dimension E from the outer surface of the vertical frame γ, as shown in FIG.

Therefore, the reinforcing member 34 can be attached by connecting the cross member 23 and the outer surface of the vertical frame 7.

In addition, the hinge bracket 26 is exemplified as having a welded integral structure of the bracket body 35 and ribs 36, 37, etc., but the bracket body 35 of the outer bracket 26 is a flat plate without any bending press processing, and is cross-shaped. It becomes possible to attach the member 23 to a protruding portion that protrudes by the above-mentioned dimension E.

This means that if there is no cross member 23 or no protrusion, it will be necessary to bend the length F by a press or the like, which is the difference from the outer surface of the vertical frame 7, making manufacturing and processing complicated. However, it is clear that the examples shown in FIGS. 4 and 6 are superior because the bracket main body 35 is weakened in terms of strength and other disadvantages.

Further, even if the bracket main body 35 of the inner bracket 26 is similarly flat, it can be fixed to the middle part of the cross member 23.

Reference numeral 38 denotes a reinforcing member attached to the inside corresponding to the reinforcing member 34, which further strengthens the welding and fixing of the vertical frame 7 and the cross member 23 together.

Further, as is clear from FIGS. 5 and 6, the front end portion 39 of the bracket main body 35 is tapered, and
Welding 41 is carried out in a holding manner from the upper side of the cross member 23 to the upper part of the front side 40, resulting in a connection structure that avoids stress concentration and effectively prevents cracking.

Further, the rib 36 is connected to the upper side of the cross member 23.

The rib 3γ has a substantially vertical shape and is connected to the rear extension portion 31, transmits the external force due to the weight of the load of the cargo box 6 acting on the support shaft 18 to the rear extension portion 31, and further strengthens the reinforcing member 34. etc. or immediately thereafter to the vertical frame 7.

In the dump mechanism 13 as shown in FIG. 1, the external force acting on the bracket 26 via the support shaft 18 during dump cutting is in the vertically downward direction, so it can be said that the vertical rib 3γ is particularly effective.

Therefore, as shown in FIGS. 3 and 5, the depth C of the recess 22 is preferably 7 to 100 times the height H1 of the vertical frame 7, but the upper side of the cross member 23 is
As close as possible to the lower surface 12 of the longitudinal girder 11 of the loading box 6, and from the upper side of the cross member 23 to the support shaft 1.
By keeping the height dimension K up to 8 small, as shown by arrow M in FIG. 6, the moment when the hinge bracket 26 falls to the left or right is suppressed as much as possible.

Further, in order to more reliably prevent the pair of brackets B6, 26 from falling to the left and right, the left and right brackets 26.2 are vertically protruded from the rear extending portion 31 of the cross member 23,
6 is provided, and the reinforcing member 42
As shown by the imaginary line in FIG. 5, the height dimension N is set to the maximum within a range where the lower surface 12 does not interfere with the upper edge of the reinforcing member 42 during maximum dumping.

Note that the upper edge of the reinforcing member 42 may be bent toward the cross member 23 to form an inverted shape.

Next, as shown in FIGS. 3 and 5, the hinge bracket 26
When viewed from the side, it is most preferable that the vertical rib 37 be asymmetrical, with the front width dimension P being long and large and the rear width dimension Q being short and small.

By making the projecting and front width dimension P long, the welding length with the cross member 23 can be made sufficiently large, and the connection can be made with sufficient strength.Furthermore, during maximum dumping, the lower surface 12 of the vertical row In order to avoid interference with
is cut into a short slanted shape so that the lower surface 12 of the longitudinal beam 11 comes into contact with it during dumping, so increasing the dimension Q will not contribute to the strength.

It should be noted that the present invention is not limited to the above-mentioned embodiments and is free to make various design changes, and the cutout shape of the recess 22 can be made into a stepped shape or a curved shape, and the shape of the cross member 23 can also be changed freely. The spacer frame 9 may be omitted, and the dump mechanism 13 may also be placed in the middle of the cargo box 6 to form a single-stage type, or other link types may be used.

Further, the hinge bracket 26 may be press-formed without using any or almost no welding.

The dump truck of the present invention is constructed as described in detail above, and has effectively achieved the intended purpose.

And there is no subframe at all, chassis frame 5
Even if the spacer frame 9 having the height dimension B which is less than the width dimension A of the vertical frame 7 is attached to the vertical frame 7 using a weak fixing device, there is no problem because no large external force is applied.
Accordingly, the weight can be reduced accordingly.

Furthermore, since the hinge bracket 26 is made to project upwardly and the support shaft 18 is attached to the vertical beam 11 of the cargo box 6 in a penetrating manner, the ground clearance of the tilting axis of the cargo box 6 is maintained at a certain level while the cargo box 6 This made it possible to lower the deck plate 19 of the dump truck, thereby achieving the contradictory goals of improving the running performance of the dump truck and improving the dirt discharge performance during dumping.

Furthermore, even if the upper corner of the rear end of the vertical frame 7.7 of the chassis frame 5 is cut out, the cross member 23 is embedded and fixed in the recesses 22, 22, so that it is sufficiently reinforced and the strength is reduced. There isn't.

Further, since the hinge bracket 26 is fixed to the cross member 23, the external force acting on the hinge bracket 26 is indirectly transmitted to the vertical frame 7, which is preferable from the viewpoint of protecting the chassis frame 5.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, and FIG. 1 is an overall side view, FIG.
4 is a sectional view taken along T-T in FIG. 3, FIG. 5 is an enlarged side sectional view of the main part, and FIG. 6 is a rear view of the same. 5... Chassis frame, 6... Loading box,
γ・・・Vertical frame, 11・・・Vertical girder, 1
8... Support shaft, 22... Recess, 23...
...Cross member, 24... End, 2G.
...Hinge bracket, 27...Upper top.

Claims (1)

[Claims] 1. Recesses 22.22 are formed by cutting out the upper corners of the rear ends of the pair of left and right vertical frames 7.7 of the chassis frame 5, and the left and right ends of the cross member 23 are used to bridge the left and right vertical frames 7.7. 24, 24 are welded and fixed in the recesses 22.22, and a hinge bracket 26.26 is fixed to the cross member 23 in an upwardly projecting manner, and the hinge bracket 26. supporting shaft 1
8 is a dump truck characterized in that the longitudinal beam 11 of the cargo box 6 is inserted into the longitudinal beam 11 of the cargo box 6, and the cargo box 6 is attached to the chassis frame 5 so as to be tiltable about the child shaft 18.