JP3676181B2 - Motor grader blade support structure - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention supports a rail fixed to a back portion of a blade so as to be reciprocally movable by a support surface of a rail guide fitted to a support portion of a guide bracket attached to a vehicle body, and the excavation load of the blade is transmitted to the rail. And a blade support structure for a motor grader configured to be received by a guide bracket via a rail guide.
[0002]
[Prior art]
FIG. 6 is a side view of the motor grader, and FIG. 7 is a side view of the blade and the support portion of the blade in the motor grader.
In FIG. 6, 100 is a motor grader, 17 is a wheel of the motor grader, 19 is an engine compartment, 18 is a cabin, 1 is a blade for excavation, 2 is a guide bracket that is fixed to the vehicle body and supports the blade 1. is there. Two sets of the blades 1 are provided on the left and right sides of the vehicle body so as to be movable in the vehicle width direction.
[0003]
In FIG. 7 showing the blade and the support portion of the blade, a bracket 16 is welded to the back portion of the blade 1, and a rail 3 is fixed to the top and bottom of the bracket 16 by welding. The rail 3 slides along the rail guide 4 fixed to the guide bracket 2 so that it can reciprocate in the width direction of the vehicle. 6 is a flange for fixing the rail guide 4 and 5 is a fixing bolt.
FIG. 8 is a perspective view showing a structure of the rail guide 4 shown in FIG. 7. As shown in the figure, the rail guide 4 has a “U” -shaped cross section, and a sliding surface inside thereof. The rail 3 is slidably fitted on the (support surface). A flange 6 is fixed to the outer end portion of the rail guide 4 and is fastened to the side surface of the guide bracket 2 by a bolt 5 inserted into a bolt hole 05 of the flange 6.
[0004]
9 to 11 show other examples of the mounting structure of the rail guide 4. FIG. 9 is a side view of the rail guide mounting portion, FIG. 10 is a perspective view of the rail guide, and FIG. 11 is a perspective view of the cover plate. FIG. 9 to 11, the rail guide 4 is fitted in the support groove 2 b of the guide bracket 2. 8 is a plate for preventing the rail guide 4 from coming off, and is fixed to the side surfaces 2a and 2a of the guide bracket 2 together with the guide bracket 2 by bolts 15 inserted into the bolt holes 015 thereof. .
[0005]
[Problems to be solved by the invention]
However, this conventional technique has the following problems.
That is, in the prior art shown in FIG. 7 and FIG. 8, the rail guide 4 is formed by tightening the flange 6 fixed to the outer end of the rail guide 4 to the side surface of the guide bracket 2 with the bolt 5. It is fixed to the bracket 2. For this reason, when the perpendicularity between the upper surface of the rail guide 4, that is, the support surface 7 and the tightening surface of the flange 6 is not properly maintained, the blade 1 transmits to the rail guide 4 via the rail 3. Due to the thrust from the blade 1 due to the excavating force, an excessive bending stress is generated in the vicinity of the connection portion between the rail guide 4 and the flange 6, and a local excessive surface pressure is generated on the pressure receiving surface of the rail guide 4. Occurring, and the occurrence of cracks in the vicinity of the connecting portion is observed.
In order to prevent the occurrence of such problems, it is necessary to increase the processing accuracy of the rail guide 4 and the flange 6 and to correctly manage the perpendicularity between the support surface 7 of the rail guide 4 and the tightening surface of the flange 6. This increases the processing time and processing cost.
[0006]
Further, in the prior art shown in FIGS. 9 to 11, since the rail guide 4 is fitted in the support groove 2b of the guide bracket 2, the rail guide from the blade 1 through the rail 3 is used. 4, the length of the rail support surface 4c, which is the pressure receiving surface of the excavation force transmitted to 4, that is, the bottom surface of the support groove 4d of the rail guide 4, is determined by the width E of the guide bracket 2, and the length cannot be adjusted. If the excavation force increases, it is necessary to increase the width E of the guide bracket 2 or the width of the rail guide 4 in order to keep the pressure of the pressure receiving surface below a predetermined value. The commonality of the molds is hindered, resulting in an increase in component costs and a decrease in component compatibility.
[0007]
In view of the problems of the prior art, the present invention prevents an increase in surface pressure between the rail and the rail guide and an increase in the bending stress of the rail guide due to excavation force while maintaining the commonality of the guide bracket mold. An object of the present invention is to provide a motor grader blade support structure having high durability and low cost.
[0008]
[Means for Solving the Problems]
Since the present invention is to solve the above problems, the rails fixed to the back of the blade, reciprocate in the supporting surface of the rail and fitted on parallel support portion engaged the rail guide of the guide bracket attached to the vehicle body In the blade support structure of the motor grader configured to receive the excavation load of the blade by the guide bracket via the rail and the rail guide,
A rail guide provided with a groove on the outer peripheral upper portion of the projecting portion are made to protrude from the width of its from the guide said support greater to than the width of the support portion of the bracket,
A cover member fixed to a side surface of the guide bracket ;
The cover member is a plate-like cover member provided with a fitting convex portion at a portion corresponding to the groove portion of the rail guide,
Suggest blade support structure of the motor grader, characterized by locking the moving groove of fitted so to the rail guide in the fitting convex portion of the projecting portion of the rail guide of the cover member.
[0009]
[0010]
According to this invention, the upper surface of the rail is pressed against the support surface of the rail guide by the excavation force transmitted from the blade to the rail, and a surface pressure is generated between the upper surface of the rail and the support surface of the rail guide.
However, in this invention, since the rail guide is formed to have a width larger than the width of the support portion of the guide bracket and protruded from the support portion, the area of the pressure receiving surface that receives the surface pressure due to the excavation force is formed. Increases and the increase in surface pressure is suppressed.
Further, the cover member fixed to the side surface of the guide bracket is engaged with the engaging portion provided on the protruding portion of the rail guide whose pressure receiving surface is enlarged as described above, and the rail guide is moved in the width direction. Since the rail guide is locked, the rail guide is stably held in the guide bracket, and the rail guide is prevented from being damaged by the pushing-up by the excavating force transmitted from the blade to the rail.
Further, the rail guide does not have a flange as in the prior art, and the pressure receiving surface is formed by a single plane extending in the width direction of the guide bracket, so that the processing accuracy of the pressure receiving surface is improved, and the prior art The generation of bending stress and the occurrence of local surface pressure increase are avoided.
[0011]
According to this invention, the width of the guide bracket is the same as that of the prior art, and the rail guide is provided with a protrusion from the width of the guide bracket to increase the area of the pressure receiving surface and reduce the surface pressure. Therefore, even when the excavating force is different, the surface pressure can be suppressed to an allowable value or less by adjusting the width of the rail guide by using a common guide bracket mold. As a result, even when the excavation force is different, the guide bracket mold can be made common, the parts cost is reduced, and the compatibility range of the parts is expanded.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described in detail with reference to the embodiments shown in the drawings. However, the dimensions, materials, shapes, relative arrangements, and the like of the component parts described in this example are not intended to limit the scope of the present invention only to specific examples unless otherwise specified. Only.
[0013]
1 is a side view of a blade support structure of a motor grader according to a first example of the present invention, FIG. 2 is a view taken along the arrow A in FIG. 1, and FIG. 3 is a sectional view taken along line BB in FIG. 4 is a perspective view of the rail guide, and FIG. 5 is a perspective view of the plate. FIG. 6 is a side view of a motor grader to which the present invention is applied, and FIG. 7 is a side view showing a prior art of blades and supporting portions of the blades in the motor grader.
[0014]
In FIG. 6, 100 is a motor grader, 17 is a wheel of the motor grader, 19 is an engine compartment, 18 is a cabin, 1 is a blade for excavation, 2 is a guide bracket fixed to the vehicle body and supporting the blade 1. is there. Two sets of the blades 1 are provided on the left and right sides of the vehicle body so as to be movable in the width direction of the vehicle.
[0015]
In FIG. 7, a bracket 16 is welded to the back of the blade 1, and a rail 3 is fixed to the top and bottom of the bracket 16 by welding. The blade 1 is fixed to the guide bracket 2. By sliding along the rail guide 4, it is possible to reciprocate in the width direction of the vehicle.
The above configuration is the same as that of the prior art. In the present invention, the flange 6 and the bolt 5 in FIG. 7 are removed, and the support structure of the rail guide to the guide bracket is improved.
[0016]
That is, in FIGS. 1 to 5, 2 is a guide bracket, 4 is a rail guide, and the rail guide 4 is fitted in the support groove 2 b of the guide bracket 2. The rail guide 4 has a “U” -shaped cross section, and the rail 3 is slidably fitted on an inner sliding surface, that is, a rail support surface 4c.
When the rail guide 4 is assembled to the guide bracket 2, as shown in FIG. 1, the rail guide 4 is formed in a vertically long shape having a protruding portion 4 a protruding in the longitudinal direction from the side surface 2 a of the guide bracket 2. Further, as shown in FIG. 4, the rail guide 4 has a groove 04 having a width and an interval at which the later-described plate 8 can be fitted with no gap in the longitudinal direction of the rail guide 4 at four locations on the outer periphery. Is formed.
[0017]
8 is a plate for preventing the rail guide 4 from coming off. As shown in FIG. 5, the plate 8 has a thickness that can be fitted into the groove 04 of the rail guide 4 and is fitted into the groove 04 on the inner periphery. fitting protrusion 8a for is projected inwardly.
Then, the plate 8, as shown in FIG. 1, this fitting protrusion 8a after having fitted into the groove 04 of the rail guides 4, a plurality of penetrating the guide bracket 2 (in this case 3) It is fastened and fixed to the side surface 2a of the guide bracket 2 by a bolt 15.
[0018]
When the motor grader having the blade support structure having such a configuration is operated, the upper surface of the rail 3 is pressed against the rail support surface 4c of the rail guide 4 by the excavation force transmitted from the blade 1 to the rail 3. A surface pressure is generated between the upper surface of the rail and the rail support surface 4c.
However, in this embodiment, projecting portions 4a projecting from the side surface 2a of the guide bracket 2 are formed on both sides of the rail guide 4, and the width of the rail guide 4 is set to the width of the support groove 2b of the guide bracket 2. Since it is formed larger than E, the area of the pressure-receiving surface responsible for the surface pressure due to the excavation force is increased by an amount corresponding to the protrusion 4a, thereby suppressing an increase in surface pressure.
The excavation force transmitted to the rail guide 4 is transmitted from the upper surface of the rail guide 4, that is, the support surface 4 b to the guide bracket 2 and received by the guide bracket 2.
[0019]
In this embodiment, the plate 8 fixed to the side surface 2a of the guide bracket 2 is engaged with the groove 04 provided in the protruding portion 4a of the rail guide 4 in which the rail support surface 4c as the pressure receiving surface is enlarged. Thus, the rail guide 4 is locked from moving in the width direction of the guide bracket 2. Thereby, it is avoided that the rail guide 4 is damaged by the pushing-up by the excavating force transmitted from the blade 1 to the rail 3.
Further, the rail guide 4 does not have a flange as in the prior art, and is a single flat surface extending in the width direction of the guide bracket 2 and forms a rail support surface 4c that is a pressure receiving surface for the excavation force. The processing accuracy of the pressure-receiving surface can be kept high, and the occurrence of bending stress and local increase in surface pressure due to the perpendicularity failure between the rail guide and the flange as in the prior art can be avoided.
[0020]
Further, according to this embodiment, the width of the guide bracket 2 is the same as that of the prior art, and the rail guide 4 is provided with the protruding portion 4a from the width of the guide bracket 2 so that the area of the pressure receiving surface is increased. Since the surface pressure can be expanded and the surface pressure can be reduced, the surface pressure can be suppressed to an allowable value or less by adjusting the width of the rail guide 4 with the same type of the guide bracket 2 even when the excavation force is different. As a result, even when the excavation force is different, the guide bracket 2 can be shared, and the range of compatibility of the parts is expanded.
[0021]
【The invention's effect】
As described above, according to the present invention, the rail guide is formed to have a width larger than the width of the support portion of the guide bracket and protrude from the support portion. The area of the pressure receiving surface is increased, and an increase in surface pressure is suppressed.
Further, the cover member fixed to the side surface of the guide bracket is engaged with the groove provided in the protruding portion of the rail guide whose pressure receiving surface is enlarged as described above via the fitting convex portion, so that the rail guide Since the movement in the width direction is locked, the rail guide is prevented from being damaged by the pushing-up by the excavating force transmitted from the blade to the rail.
Furthermore, since the rail guide forms the pressure receiving surface with a single plane extending in the width direction of the guide bracket, the processing accuracy of the pressure receiving surface can be kept high, and the occurrence of bending stress as in the prior art and local As described above, an increase in surface pressure between the rail and the rail guide and an increase in bending stress of the rail guide are prevented, and high durability is improved.
[0022]
In addition, the guide bracket width can be expanded and the surface pressure can be reduced while maintaining the same width of the guide bracket as in the conventional technology. Thus, the cost of parts is reduced, and the range of compatibility of parts is expanded.
[Brief description of the drawings]
FIG. 1 is a side view of a blade support structure of a motor grader according to an embodiment of the present invention.
FIG. 2 is a view taken in the direction of arrow A in FIG.
3 is a cross-sectional view taken along the line BB in FIG.
FIG. 4 is a perspective view of a rail guide.
FIG. 5 is a perspective view of a plate.
FIG. 6 is a side view of a motor grader to which the present invention is applied.
FIG. 7 is a side view showing a conventional technique of a blade and a supporting portion of the blade in a motor grader.
FIG. 8 is a perspective view showing a structure of a rail guide 4 according to a conventional technique.
FIG. 9 is a side view of a rail guide mounting portion according to the prior art.
FIG. 10 is a perspective view of a rail guide according to a conventional technique.
FIG. 11 is a perspective view of a cover plate according to the prior art.
[Explanation of symbols]
1 Blade 2 guide bracket 2a side 2b supporting grooves 3 rail 4 rail guide 4a projecting portion 4b supporting surface 4c rail support surface 04 groove 8 plates 8a fitting projection 15 volts 100 motor grader

Claims (1)

A rail fixed to the back portion of the blade is supported so as to be reciprocally movable by a support surface of a rail guide fitted to a support portion parallel to the rail of the guide bracket attached to the vehicle body, and the excavation load of the blade is In the blade support structure of the motor grader configured to be received by the guide bracket via the rail and the rail guide,
A rail guide provided with a groove on the outer peripheral upper portion of the projecting portion are made to protrude from the width of its from the guide said support greater to than the width of the support portion of the bracket,
A cover member fixed to a side surface of the guide bracket ;
The cover member is a plate-like cover member provided with a fitting convex portion at a portion corresponding to the groove portion of the rail guide,
Blade support structure of the motor grader, characterized in that locking grooves movement fitted so to the rail guide in the fitting convex portion of the projecting portion of the rail guide of the cover member.

Images