JPH11324006A - Rise and fall device of blade - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rise and fall device of a blade which can securely prevent a hydraulic cylinder or a hydraulic pipe from being damaged by sand and soil. SOLUTION: The basal end of a lower side cover plate 33 is rotatably pivoted at the lower part of a bracket 32 and the basal end of an upper side cover plate 35 is rotatably pivoted at the upper part of the bracket 32. Blades 37 are rotatably pivoted at the tip of the lower side cover plate 33 and the upper side cover plate 35 respectively. These lower and upper side cover plates 33, 35 are formed to have a U-shaped section and the opened sides of the U-shaped section are arranged to face each other. A hydraulic cylinder 43 for rise and fall of the blade and hydraulic pipe 44 to feed hydraulic oil to the hydraulic cylinder 43 or extract the oil therefrom are built in between the lower and upper side cover plates 33, 35.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a blade elevating device for moving a blade up and down by a hydraulic cylinder.

[0002]

2. Description of the Related Art As shown in FIG. 3, for example, in a hydraulic shovel, an upper revolving structure 12 is rotatably provided on a lower traveling structure 11, and a cab 13 for protecting an operator is provided on one side of the upper revolving structure 12. The upper working body 12 is provided with a front working device 14 at a substantially central portion thereof.

[0003] The front working device 14 includes an upper revolving unit 12.
A boom 15 pivoted vertically by a boom cylinder 15a is pivotally supported, and an offset boom pivoted left and right by an offset cylinder 16a above the boom 15.
An arm 17 rotated by an arm cylinder 17a is pivotally supported at the tip of the offset boom 16,
A bucket 18 that is rotated by a bucket cylinder 18a is pivotally supported at the tip of the arm 17.

In a hydraulic shovel or the like having such an offset boom 16, a blade 20 used for earth discharging work is provided on the lower traveling body 11 so as to be able to move up and down.

[0005] As shown in FIG. 4, a conventional blade elevating device 21 for elevating and lowering the blade 20 includes a traveling frame 22.
A bracket 23 is integrally attached to the bracket 23 by welding or the like. The hydraulic cylinder 26 for raising and lowering the blade arranged on the blade raising and lowering arm 24 is rotatably connected to a shaft support 27, and the blade 20 is integrated with the tip of the blade raising and lowering arm 24 by welding or the like. Installed.

A guard cover 28 for guarding the hydraulic cylinder 26 is mounted on the cylinder body of the hydraulic cylinder 26. A hydraulic pipe 29 for supplying and discharging hydraulic oil to and from the hydraulic cylinder 26 is provided outside the blade elevating device 21 between the traveling frame 22 and the hydraulic cylinder 26.

[0007]

As described above, the blade
The mounting position of the hydraulic cylinder 26 that is used to raise and lower the hydraulic cylinder 20 is located above the blade lifting arm 24.Therefore, the hydraulic cylinder 26
There is a risk of damaging 26 and hydraulic piping 29. Further, the guard cover 28 provided partially does not reliably prevent the above-mentioned fear.

Further, in the conventional blade lifting / lowering device 21, the blade lifting / lowering arm 24 is rotated about the pivot 25 by the expansion and contraction of the hydraulic cylinder 26 to change the height position of the blade 20, but the height of the blade 20 is changed. Depending on the position, the blade tip angle α also changes.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a blade lifting device capable of reliably preventing a hydraulic cylinder and a hydraulic pipe from being damaged by earth and sand. In addition, it is another object of the present invention to provide a blade elevating device capable of maintaining a constant blade tip angle.

[0010]

According to a first aspect of the present invention, there is provided a mounting base, a lower cover plate having a base end rotatably supported by the mounting base, and an upper side of the lower cover plate. An upper cover plate whose base end is rotatably supported by the mounting base, a blade rotatably supported by the lower cover plate and a distal end of the upper cover plate, and a lower cover plate. Blade lifting / lowering provided with a hydraulic cylinder for raising / lowering a blade provided between the upper and lower cover plates, and a hydraulic pipe provided between the lower and upper cover plates to supply and discharge hydraulic oil to and from the hydraulic cylinder Device.

Thus, the upper cover plate protects the hydraulic cylinder and the hydraulic piping from, for example, spilled earth and sand, and the lower cover plate protects the hydraulic cylinder and the hydraulic piping from, for example, rocks protruding from the ground.

According to a second aspect of the present invention, in the blade elevating device according to the first aspect, a concave portion is formed on the lower cover plate and the upper cover plate on mutually opposing sides.

Thus, the hydraulic cylinders and the hydraulic piping arranged in the recesses of the lower cover plate and the upper cover plate can be protected not only from the vertical direction but also from obstacles colliding from the left and right sides, and the concave shape can be used. Structural strength can be ensured.

According to a third aspect of the present invention, in the blade elevating device according to the first or second aspect, the lower cover plate and the upper cover plate are provided to be parallel and equal in length.

[0015] This makes it possible to maintain the blade angle of the blade with good working efficiency and perform efficient blade work regardless of the height of the blade.

According to a fourth aspect of the present invention, in the blade elevating device according to any one of the first to third aspects, the hydraulic cylinder is formed on a diagonal line of four shaft supporting portions of a lower cover plate and an upper cover plate. Are pivotally supported between the pivotal support portions.

[0017] Thus, the shaft support of the lower cover plate and the upper cover plate can be used as the shaft support of the hydraulic cylinder, and the shaft support structure is simplified.

[0018]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIG.
This will be described with reference to FIG.

As shown in FIG. 1, a bracket 32 as an attachment base is integrally attached to a traveling frame 31 such as a hydraulic excavator, a backhoe or a bulldozer by welding or the like, and a lower cover plate 33 is attached to a lower portion of the bracket 32. The base end is rotatably supported by a shaft support 34.

A base end of an upper cover plate 35 located above the lower cover plate 33 is rotatably supported by a shaft support 36 on the upper portion of the bracket 32.

A bracket 38 projecting from the lower portion of the back surface of the blade 37 is provided at the tip of the lower cover plate 33 and the upper cover plate 35.
And a bracket 39 protruding from the upper part of the back of the blade 37
Are rotatably supported by the respective shaft support portions 41 and 42.

Since the lower cover plate 33 and the upper cover plate 35 are provided in parallel with each other and have the same length, the bracket 32, the lower cover plate 33, the upper cover plate 35, and the blade 37 A parallel movement mechanism (parallel crank mechanism) using parallel links is configured.

Between the lower cover plate 33 and the upper cover plate 35,
A hydraulic cylinder 43 for raising and lowering the blade, and the hydraulic cylinder 43
A hydraulic pipe 44 for supplying and discharging hydraulic oil is provided at 43.

The hydraulic cylinder 43 includes a cylinder body between the four supporting portions 34, 36, 41, and 42 of the lower covering plate 33 and the upper covering plate 35, which are located on one diagonal line. And the distal end of the piston rod 43a are pivotally supported. Note that the hydraulic cylinder 43 may be supported between the shaft supports 34 and 42 located on the other diagonal line.

As shown in FIG. 2, the lower cover plate 33 and the upper cover plate 35 are each formed in a U-shaped cross section by a horizontal plate portion 45 and a vertical plate portion 46, and concave portions are formed on opposing sides. 47
Are formed, and the hydraulic cylinder 43 and the hydraulic pipe 44 are built in the recess 47. The concave portion 47 may be formed in a plate member having an arc-shaped cross section.

Next, the operation of the embodiment shown in FIGS. 1 and 2 will be described.

When the piston rod 43a of the hydraulic cylinder 43 is actuated in the contracting direction, as shown by a two-dot chain line in FIG. The upper cover plate 35 is rotated upward while the shaft supports 34 and 36 are parallel to the fulcrum, and the blade 37 is raised.

On the other hand, the piston rod 43 of the hydraulic cylinder 43
When a is actuated in the direction in which a is extended, as shown by the solid line in FIG. 1, the space between the diagonally supported shafts 36, 41 is enlarged, so that the lower cover plate 33 and the upper cover plate 35 connect the shaft supports 34, 36 to each other. The blade 37 is lowered while rotating in parallel with the fulcrum.

When the blade 37 is moved up and down, the lower cover plate 33 and the upper cover plate 35 are parallel links provided in parallel and of equal length.
The blade tip angle α with good soil removal efficiency can be maintained and the blade
Efficient blade work can be performed regardless of the height position of 37.

Since the hydraulic cylinder 43 and the hydraulic pipe 44 are provided between the lower cover plate 33 and the upper cover plate 35, the upper cover plate
Hydraulic cylinder from earth and sand dropped from above by 35
43 and the hydraulic pipe 44 can be protected, and the lower cover plate 33 can protect the hydraulic cylinder 43 and the hydraulic pipe 44 from being pushed up by rocks or the like protruding from the ground.

Further, by enclosing the hydraulic cylinder 43 and the hydraulic piping 44 with the lower cover plate 33 and the upper cover plate 35, the appearance becomes clearer and the appearance becomes better.

The hydraulic cylinder 43 is rotatably supported between the diagonal bearing portions 36, 41 of the four bearing portions 34, 36, 41, 42 of the lower cover plate 33 and the upper cover plate 35. The shaft supports 36 and 41 of the lower cover plate 33 and the upper cover plate 35 can also serve as the shaft support of the hydraulic cylinder 43, thereby simplifying the shaft support structure.

The lower cover plate 33 and the upper cover plate 35 are arranged as shown in FIG.
As shown in FIG. 3, each of the concave portions 47 has a U-shaped cross section, and the concave portions 47 are arranged so as to face each other, so that the horizontal portions forming the concave portions 47 of the lower cover plate 33 and the upper cover plate 35 are formed. The plate portion 45 and the vertical plate portion 46 can protect the hydraulic cylinder 43 and the hydraulic pipe 44 not only from the upper and lower portions but also from obstacles colliding from the left and right sides. In addition, structural strength can be ensured by the concave portion 47 having the U-shaped cross section.

The present invention can be applied not only to a hydraulic excavator but also to a backhoe or a bulldozer.

[0035]

According to the first aspect of the present invention, since the hydraulic cylinder and the hydraulic piping are built in between the lower cover plate and the upper cover plate, the hydraulic cylinder can be removed from the spilled soil and the like by the upper cover plate. And the hydraulic pipes can be protected, and the lower cover plate can protect the hydraulic cylinders and the hydraulic pipes from rocks and the like that protrude from the ground, and can reliably prevent their breakage.

According to the second aspect of the present invention, since the lower cover plate and the upper cover plate have recesses formed on the sides facing each other, the hydraulic pressure disposed in the recesses of the lower cover plate and the upper cover plate is formed. Cylinders and hydraulic piping can be protected not only from the vertical direction but also from obstacles colliding from the left and right sides,
Due to the concave shape, the structural strength of the lower cover plate and the upper cover plate can be secured.

According to the third aspect of the present invention, since the lower cover plate and the upper cover plate are provided in parallel and equal in length, the blade tip angle can be kept constant, and the blade tip with good working efficiency can be maintained. The angle can be maintained, and efficient blade work can be performed regardless of the height position of the blade.

According to the fourth aspect of the present invention, the hydraulic cylinder is pivotally supported between the diagonally supported ones of the four support portions of the lower cover plate and the upper cover plate. In addition, the shaft supporting portion of the upper cover plate and the shaft supporting portion of the hydraulic cylinder can also be used, and the shaft supporting structure can be simplified.

[Brief description of the drawings]

FIG. 1 is a front view showing an embodiment of a blade lifting device according to the present invention.

FIG. 2 is a sectional view taken along line II-II of FIG.

FIG. 3 is a front view of a hydraulic shovel to which the present invention is applied.

FIG. 4 is a front view showing a conventional blade elevating device.

[Explanation of symbols]

 32 Bracket as mounting base 33 Lower cover plate 34, 36, 41, 42 Shaft support 35 Upper cover plate 37 Blade 43 Hydraulic cylinder 44 Hydraulic piping 47 Recess

Claims (4)

[Claims] 1. A mounting base, a lower cover plate whose base end is rotatably supported by the mounting base, and a base end rotatably mounted on the mounting base above the lower cover plate. A supported upper cover plate, a blade rotatably supported at the tip of the lower cover plate and the upper cover plate, respectively, and a blade lift provided between the lower cover plate and the upper cover plate A hydraulic cylinder provided between the lower cover plate and the upper cover plate for supplying and discharging hydraulic oil to and from the hydraulic cylinder. 2. The blade lifting device according to claim 1, wherein the lower cover plate and the upper cover plate have recesses formed on the sides facing each other. 3. The blade lifting device according to claim 1, wherein the lower cover plate and the upper cover plate are provided in parallel and equal length. 4. The hydraulic cylinder according to claim 1, wherein the hydraulic cylinder is rotatably supported between diagonally positioned ones of the four support portions of the lower cover plate and the upper cover plate. A blade lifting / lowering device according to any one of the above.