JP4023645B2 - Hydraulic excavator offset angle sensor protective mounting structure - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a protective mounting structure that protects an offset angle sensor from being damaged by interference with an obstacle during operation of the working machine in a hydraulic excavator equipped with a working machine having an offset boom configuration.
[0002]
[Prior art]
2. Description of the Related Art A hydraulic excavator is known in which an upper turning vehicle body is turnably attached to a lower vehicle body provided with a traveling body, and an operating machine having a cab and an offset boom structure is mounted on the upper turning vehicle body. The working machine of the offset boom configuration includes a base boom attached to the upper turning vehicle body so as to be swingable up and down, an offset boom connected to the base boom so as to be swingable left and right, and an arm connected to the offset boom so as to be swingable up and down. And a bucket or the like attached to the arm so as to be swingable up and down.
[0003]
In a hydraulic excavator equipped with a boom having the offset configuration described above, an offset angle sensor is installed in order to prevent the offset boom from swinging toward the side where the operator cab is located in an area that may interfere with the operator cab. It is provided at the swing point of the offset boom or the pivot point of the offset drive link means.
For example, as shown in Japanese Utility Model Laid-Open No. 2-5439, an offset angle sensor is attached to an upper position of an offset swing fulcrum pin that connects a base boom and an offset boom so as to freely swing left and right.
[0004]
In the above-described offset angle sensor mounting structure, the offset angle sensor protrudes upward from the upper surface of the offset boom.
Therefore, when the base boom is swung upward and the offset boom is lifted upward, and there is an obstacle at the upper position of the offset boom, the aforementioned offset angle sensor is May collide. If the offset angle sensor collides with an obstacle, the offset angle sensor may be damaged.
[0005]
In order to solve this problem, the offset angle sensor is covered with a cover to prevent the cover from interfering with the obstacle when the offset boom is lifted upward so that the offset angle sensor does not interfere with the obstacle. It has been proposed.
[0006]
[Problems to be solved by the invention]
Since the base boom swings upward by the base boom cylinder, the offset boom is lifted upward by the hydraulic pressure of the base boom cylinder.
For this reason, the upward lifting force of the offset boom is large, and when the cover interferes with an obstacle as described above, the cover is pressed against the obstacle with a strong force, and the cover itself is deformed to interfere with the offset angle sensor. There is a risk of damage.
[0007]
Therefore, an object of the present invention is to provide a protective mounting structure for an offset angle sensor of a hydraulic excavator that can solve the above-described problems.
[0008]
[Means for solving the problems and actions / effects]
A first invention is a hydraulic excavator in which a work machine 6 having an offset boom structure in which an offset boom 8 is connected to a base boom 7 so as to be swingable in the left-right direction is mounted.
An offset boom connecting bracket portion 32 composed of an upper bearing portion 30 and a lower bearing portion 31 is formed at the tip of the base boom 7,
A first laterally projecting lateral piece 25 and a second laterally projecting lateral piece 26 are integrally provided on the left and right sides of the upper bearing portion 30 with a space in the vertical direction, and the offset stay 13 is attached. Forming an offset stay mounting bracket 38;
An offset angle sensor 50 is attached to the upper surface of the first laterally projecting horizontal piece 25 on the upper side of the offset stay mounting bracket portion 38 ,
The offset angle sensor protection means 60 is provided on the upper surface of the bearing portion 30 above the offset boom connection bracket portion 32, and the upper end surface of the offset angle sensor protection means 60 protrudes higher than the offset angle sensor 50. This is an offset angle sensor protective mounting structure for a hydraulic excavator.
[0009]
According to the first invention, since the upper end surface of the offset angle protection sensor 60 that prevents the offset angle sensor 50 from interfering with an obstacle projects higher than the offset angle sensor 50, the work implement 6 is swung upward. When the offset boom 8 is lifted upward by moving and there is an obstacle at the height position of the offset boom 8, the offset angle sensor protection means 60 interferes with the obstacle first to offset it. It is possible to prevent the angle sensor 50 from interfering with an obstacle.
[0010]
In addition, even if the offset angle sensor protection means 60 is pressed against an obstacle with a strong force and deformed, the offset angle sensor 50 is located at a remote position, so that no damage is caused.
[0011]
According to a second invention, in the first invention, the vertical pin 40 for connecting the offset stay 13 for connecting the offset stay 13 is inserted from the lower surface of the offset stay mounting bracket portion 38 and protrudes from the upper surface of the offset stay mounting bracket portion 38. The vertical pin 40 and the rotation axis 53 of the offset angle sensor 50 are concentric positions,
A lever link 54 is provided between the rotating shaft 53 and the offset stay 13 to transmit the left-right swinging motion of the offset stay 13 to the rotating shaft 53, and the lever link 54 is lower than the upper end surface of the offset angle sensor protection means 60. It is an offset angle sensor protective mounting structure of a hydraulic excavator at a position.
[0012]
According to the second invention, the offset stay connecting vertical pin 40 can be inserted and removed from the lower surface of the offset stay mounting bracket portion 38, and the vertical pin 40 does not interfere with the offset angle sensor 50. The offset stay 13 can be coupled and separated while the offset angle sensor 50 is attached to the upper surface of the portion 38, and the offset stay 13 can be easily coupled and separated.
[0013]
Further, since the lever link 54 that rotates the rotation shaft 53 of the offset angle sensor 50 by the left and right swing of the offset stay 13 is at a position lower than the upper end surface of the offset angle sensor protection means 60, the lever link 54 becomes an obstacle. Interference can be prevented.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
As shown in FIG. 1, an upper turning vehicle body 3 is attached to a lower vehicle body 2 having a traveling body 1 by a turning mechanism 4 so as to be turnable. A driver's cab 5 is attached to the upper turning vehicle body 3 and a work machine 6 is mounted so as to be swingable up and down.
[0015]
The working machine 6 includes a base boom 7 attached to the upper turning body 3 so as to be swingable up and down, an offset boom 8 connected to the base boom 7 so as to be swingable left and right, and connected to the offset boom 8 so as to be swingable left and right. A swing bracket 9, an arm 10 connected to the swing bracket 9 so as to swing up and down, and a bucket 11 attached to the arm 10 so as to swing up and down. The work machine 6 has an offset boom configuration. .
[0016]
A base boom cylinder 12 is connected across the upper turning vehicle body 3 and the base boom 7. An offset stay 13 is connected to the base boom 7 and the swing bracket 9, and an offset cylinder 14 is connected to the offset boom 8 and the swing bracket 9. On the other hand, the offset boom 8 swings left and right, and the arm 10 translates left and right.
An arm cylinder 15 is connected across the swing bracket 9 and the arm 10. The bucket 11 swings up and down by a bucket cylinder 16.
[0017]
The base boom 7 has a shape in which a bracket member 18 is fixed to a distal end portion of a long boom body 17.
The bracket member 18 has a main body 20 having a predetermined width (horizontal dimension), thickness (front-rear dimension) and length (vertical dimension), and a front surface of the main body 20 spaced in the vertical direction. The first, second, third, and fourth forward projecting lateral pieces 21, 22, 23, and 24 that are integrally provided toward the front and the first and second forward projecting lateral pieces that are closer to the upper side. The first and second laterally projecting lateral pieces 25 and 26 that are integrally provided on the left and right side surfaces of 21 and 22 toward the left and right sides, and the lowermost fourth front projecting lateral piece 24 First and second projecting vertical pieces 27 and 28 are provided integrally on the left and right sides of the lower surface and the main body 20 toward the front.
[0018]
The first, second, third, and fourth forward projecting horizontal pieces 21, 22, 23, and 24 are formed with concentric vertical holes 29 that open in the upper and lower surfaces, and the first front projecting lateral pieces. An upper bearing portion 30 having an U-shaped cross section is formed by the piece 21, the second front protruding horizontal piece 22 and the main body portion 20, and the third front protruding horizontal piece 23, the fourth front protruding horizontal piece 24 and the main body are formed. A lower bearing portion 31 having a U-shaped cross section is formed at the portion 20, and an offset boom connecting bracket portion 32 is formed by the upper bearing portion 30 and the lower bearing portion 31.
[0019]
The upper mounting leg portion 33 of the offset boom 8 is fitted into the upper bearing portion 30, the lower mounting leg portion 34 of the offset boom 8 is fitted into the lower bearing portion 31, and each vertical hole 29 and the mounting leg portion are fitted. A vertical pin 36 for connecting an offset boom in the vertical direction is fitted into the vertical holes 35 of 32 and 33 to connect the offset boom 8 to the offset boom connection bracket portion 32 so as to be swingable in the left-right direction.
[0020]
The first and second laterally projecting horizontal pieces 25 and 26 are formed with vertical holes 37 that are opened in the upper and lower surfaces and directed in the vertical direction to form offset stay mounting bracket portions 38.
One end portion of the offset stay 13 is fitted into an offset stay mounting bracket 38, and a vertical hole 39 formed in the one end portion and a vertical pin 40 for connecting an offset stay in the vertical direction are inserted and offset. One end portion of the offset stay 13 is attached to the stay mounting bracket portion 38 so as to be able to swing left and right.
[0021]
A horizontal hole 41 is formed concentrically in the first and second protruding vertical pieces 27 and 28 to form a base boom cylinder connecting bracket portion 42.
The piston rod 12a of the base boom cylinder 12 is connected to the base boom cylinder connection bracket portion 42 by a lateral pin 43.
[0022]
The main body 51 of the offset angle sensor 50 is attached to the upper surface of the first laterally projecting horizontal piece 25 (the upper surface of the offset stay mounting bracket portion 38) with a bolt 52, and the rotating shaft 53 of the offset angle sensor 50 is the vertical pin 40. The upper part of the rotating shaft 53 protrudes from the upper surface of the main body 51, and one end of the lever link 54 is fixed to the protruding part.
A long hole 55 is formed at the other end of the lever link 54, and a bolt 56 inserted through the long hole 55 is screwed into a nut member 57 fixed to the upper surface of the offset stay 13.
[0023]
As a result, when the offset stay 13 swings left and right around the vertical pin 40, the lever link 54 swings left and right and the rotating shaft 53 rotates, so that the offset amount (left and right swing angle) of the offset frame 8 is offset. It can be detected by the angle sensor 50.
[0024]
The vertical pin 40 is inserted upward from the lower surface of the second laterally projecting horizontal piece 26 (the lower surface of the offset stay mounting bracket portion 38), and the vertical pin 40 is located above the upper surface of the first laterally projected horizontal piece 25. Is not protruded so as not to interfere with the offset angle sensor 50. Reference numeral 40a denotes a bolt which prevents falling off.
[0025]
The upper surface of the first front protruding horizontal piece 21 (the upper surface of the upper bearing portion 30) is higher than the upper surface of the first side protruding horizontal piece 25 (the upper surface of the offset stay mounting bracket portion 38). The offset angle sensor protection means 60 is integrally provided at a position closer to the first side protruding horizontal piece 25 than the vertical pin 36 of the protruding horizontal piece 21 (that is, a position close to the offset angle sensor 50).
The offset angle sensor protection means 60 is a rigid projection having a predetermined width, thickness and length, and its upper end surface protrudes higher than the offset angle sensor 50 and the lever link 54. The offset angle sensor protection means 60 is at the same position in the front-rear direction as the offset angle sensor 50 (that is, a position parallel to the offset angle sensor 50).
[0026]
Thus, the piston rod 12a of the base boom cylinder 12 is extended and operated to swing the work implement 6 upward, and when the offset boom 8 is lifted upward, the offset boom 8 is moved in the height direction. When there is an obstacle at the position, the offset angle sensor protection means 60 interferes with the obstacle.
Even if the offset angle sensor protection means 60 is pressed against the obstacle by the hydraulic pressure of the base boom cylinder 12, the offset angle sensor protection means 60 is not deformed, so that the offset angle sensor 50 does not interfere with the obstacle. .
[0027]
Even if the offset angle protection means 60 is deformed or the like, the offset angle sensor 50 exerted by an obstacle will not be damaged because the offset angle protection means 60 and the offset angle sensor 50 are located at a distance.
[0028]
Moreover, since the offset angle sensor protection means 60 does not get in the way when the offset angle sensor 50 is replaced, the replacement work is easy.
[0029]
In addition, since the bracket member 18 having a complicated shape is manufactured by casting, the boom body 17 is made of sheet metal, and the bracket member 18 is fixed to the boom body 19 by welding or the like, the base boom 7 can be manufactured. is there.
[0030]
The bracket member 18 may be integrated with the boom body 17. That is, the brackets described above may be formed at the tip of the base boom 7.
[Brief description of the drawings]
FIG. 1 is a front view of a hydraulic excavator.
FIG. 2 is an enlarged detailed front view of a connecting portion between a base boom and an offset boom.
3 is a left side view of FIG.
4 is a plan view of FIG. 2. FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Running body 3 ... Upper turning vehicle body 5 ... Driver's cab 6 ... Working machine 7 ... Base boom 8 ... Offset boom 9 ... Swing bracket 10 ... Arm 11 ... Bucket 12 ... Base boom rinser 13 ... Offset stay 14 ... Offset cylinder DESCRIPTION OF SYMBOLS 15 ... Arm cylinder 16 ... Bucket cylinder 17 ... Boom main body 18 ... Offset boom 21 ... 1st front protrusion horizontal piece 22 ... 2nd front protrusion horizontal piece 23 ... 3rd front protrusion horizontal piece 24 ... 4th front protrusion horizontal piece 25 ... 1st side protrusion horizontal piece 26 ... 2nd side protrusion horizontal piece 27 ... 1st protrusion vertical piece 28 ... 2nd protrusion vertical piece 30 ... Upper bearing part 31 ... Lower bearing part 32 ... Offset boom connection bracket Part 36: Vertical pin 38 for offset boom connection ... Offset stay mounting bracket part 40: Vertical pin 42 for offset stay connection ... Base boom cylinder connection block Socket 50 ... offset angle sensor 53 ... rotating shaft 54 ... lever link 60 ... offset angle sensor protection means

Claims (2)

In a hydraulic excavator in which a working machine (6) having an offset boom structure in which an offset boom (8) is connected to a base boom (7) so as to be swingable in the left-right direction is mounted.
Forming an offset boom connecting bracket portion (32) comprising an upper bearing portion (30) and a lower bearing portion (31) at the tip of the base boom (7);
A first laterally projecting lateral piece (25) and a second laterally projecting lateral piece (26) are integrally provided on the left and right side portions of the upper bearing portion (30) with a space in the vertical direction. Forming an offset stay mounting bracket portion (38) for mounting the offset stay (13);
An offset angle sensor (50) is mounted on the upper surface of the first laterally projecting lateral piece (25) on the upper side of the offset stay mounting bracket portion ( 38 ) ,
An offset angle sensor protection means (60) is provided on the upper surface of the bearing part (30) on the upper side of the offset boom connection bracket part (32), and the upper end surface of the offset angle sensor protection means (60) is connected to the offset angle sensor (50). ) A mounting structure for protecting the offset angle sensor of a hydraulic excavator, wherein the offset angle sensor is protruded higher than. A vertical pin (40) for connecting the offset stay ( 13 ) is inserted from the lower surface of the offset stay mounting bracket portion (38) and fixed so as not to protrude from the upper surface of the offset stay mounting bracket portion (38). Then, the vertical pin (40) and the rotation axis (53) of the offset angle sensor (50) are concentric,
A lever link (54) is provided between the rotating shaft (53) and the offset stay (13) to transmit the left-right swinging motion of the offset stay (13) to the rotating shaft (53). The offset angle sensor protection mounting structure for a hydraulic excavator according to claim 1, wherein the offset angle sensor protection means (60) is positioned lower than the upper end surface of the offset angle sensor protection means (60).

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