JP3848009B2 - Construction equipment working equipment - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a working device for a construction machine having an angle sensor that measures a relative rotation angle between members connected to each other such as a boom and an arm of a hydraulic excavator.
[0002]
[Prior art]
A construction machine working apparatus having the angle sensor described above is disclosed in, for example, Japanese Utility Model Laid-Open No. 3-106406. In a conventional apparatus, a relative angle between a boom and an arm that are rotatably connected to each other via a pin is detected by an angle sensor attached to a side surface of the boom. The angle sensor includes an input shaft, a sensor unit that detects a rotation angle of the input shaft, and a case that accommodates them. The input shaft is connected to the arm by a lever. When the arm is rotated with respect to the pin, the input shaft is rotated by a lever that interlocks with the rotation of the arm. The rotation angle of the input shaft is detected by the sensor unit, and the relative angle of the arm is obtained based on the detected value. And the detection signal detected by the sensor part is transmitted to the controller of the hydraulic excavator through a connection cable such as a harness.
[0003]
[Problems to be solved by the invention]
By the way, the angle sensor may be provided with a protective cover. However, since the protective cover is provided with a hole through which the above-mentioned lever penetrates, the waterproof property for the internal angle sensor is incomplete, and the connection cable for the angle sensor is provided. There is a risk that water or the like may enter the inside of the main body from the take-out portion or the like and cause a failure.
[0004]
An object of the present invention is to provide a working device for a construction machine that improves the waterproofness of an angle sensor.
[0005]
[Means for Solving the Problems]
An embodiment of the invention will be described with reference to FIGS.
(1) The invention of claim 1 includes the first member 4, the second member 3 to which the first member 4 is rotatably connected via the integrally provided connecting member 22, and the connecting member. The angle sensor 21 having a built-in sensor portion 21c for detecting the rotation angle of the input shaft 21b in the case 21a fixed to the 22nd, and the input shaft 21b is driven to rotate in conjunction with the rotation of the first member 4. 1 is applied to a working device of a construction machine including a member 4 and a transmission member 23 for connecting the input shaft 21b. (A) A recess 22a is formed on the end surface in the axial direction of the connecting member 22, and a case 21a is formed in the recess 22a. (B) The above-described object is achieved by providing the seal member 28 that seals the inside of the recess by sealing between the outer peripheral surface 217 of the case 21a and the inner peripheral surface 221 of the recess 22a.
(2) According to the invention of claim 2, in the working device according to claim 1, a hole 28c penetrating in the axial direction of the input shaft 21b is provided in the seal member 28, and the cable 216 from the sensor portion 21c is connected to the hole 28c. Through the recess 22a.
[0006]
In the section of the means for solving the above-described problems for explaining the configuration of the present invention, the drawings of the embodiments of the invention are used for easy understanding of the present invention. The form is not limited.
[0007]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to FIGS. FIG. 9 is a diagram showing a schematic configuration of the hydraulic excavator, and the upper traveling body 2 is provided on the lower traveling body 1 via a turning mechanism. The upper swing body 2 is provided with a front working device 6 constituted by a boom 3, an arm 4 and a bucket 5. The boom 3, the arm 4, and the bucket 5 are connected so as to be rotatable with respect to the pins 12, 22, and 32, respectively.
[0008]
FIG. 1 is a view for explaining a mounting state of an angle sensor in a working device according to the present invention, and is a cross-sectional view of a principal part taken along line II in FIG. As described above, the boom 3 and the arm 4 are connected to each other by a front pin (hereinafter referred to as a front pin) so as to be rotatable. The front pin 22 is fixed to the boom 3, and the arm 4 is rotatably connected to the front pin 22. A concave portion 22a having a circular cross section is formed coaxially with the axial center of the end surface of the front pin 22, and the angle sensor 21 is accommodated in the concave portion 22a. The angle sensor 21 has a case 21a, an input shaft 21b, and a sensor portion 21c. The case 21a is accommodated in the recess 22a so that the input shaft 21b protrudes from the end surface of the front pin 22.
[0009]
A flange 218 protrudes from the end surface of the case 21 a, and the angle sensor 21 is attached to the front pin 22 by fixing the flange 218 to the end surface 22 b of the front pin 22 using a bolt 25. Reference numeral 26 denotes a protective cover for protecting the input shaft 21b from the collision of earth and sand or rocks, and is attached to the front pin 22 integrally with the angle sensor 21 by the bolt 25 described above.
[0010]
One end of a lever 23 is connected to the input shaft 21 b protruding from the end surface of the front pin 22, and the other end of the lever 23 is fixed to the arm 4 by a bracket 27. Therefore, when the angle of the arm 4 is changed, that is, when the arm 4 is rotated about the front pin 22 as a fulcrum, the input shaft 21 b of the angle sensor 21 is rotationally driven by the lever 23 fixed to the arm 4.
[0011]
The concave portion 22a is preferably formed so as to be coaxial with the front pin 22, from the viewpoint of detection accuracy, but the accuracy with which the coaxiality between the input shaft 21b of the angle sensor 21 disposed in the concave portion 22a and the front pin 22 is allowed. The recess 22a may not be strictly coaxial with the front pin 22 as long as it is within the guaranteed range.
[0012]
FIG. 2 is a cross-sectional view showing details of the angle sensor 21. The input shaft 21b is attached to the case 21a via a bearing 212. A seal 213 for preventing intrusion of water, oil, mud or the like in the case is provided at the upper part of the bearing 212 in the figure. Reference numeral 214 denotes a resistor that is fixed to the input shaft and rotates integrally with the input shaft. A wiper 215 is disposed at a position facing the resistor 214. The sensor unit 21c described above includes a resistor 214 and a wiper 215. When the input shaft 21b is rotationally driven by the lever 23, the resistor 214 rotates, the relative position between the resistor 214 and the wiper 215 changes, and the output voltage of the resistor 214 changes. This output voltage change is transmitted to the controller 29 of the hydraulic excavator via the cable 216 connected to the wiper 215, and the angle change of the arm 4 with respect to the boom 3 is calculated.
[0013]
The case 21a is provided with a seal member 28, which seals between the side wall surface 221 of the recess 22a and the side surface 217 of the case 21a. As a result, it is possible to prevent water or the like from entering the bottom of the case 21a in which the resistor 214 and the wiper 215 as the sensor unit 21c are housed, that is, the bottom of the recess 22a. In addition, intrusion of water from the input shaft 21b portion can be substantially prevented by the seal 213.
[0014]
The cable 216 penetrates the inside of the case 21 a and the seal member 28, is drawn out of the sensor from the flange 218, and is connected to the controller 29. 3A and 3B are diagrams showing details of the seal member 28 shown in FIG. 2, wherein FIG. 3A is a plan view and FIG. 3B is a cross-sectional view. The seal member 28 includes an O-ring portion 28a and a cable penetration portion 28b, and is integrally formed. A hole 28c through which the cable 216 passes is formed in the cable penetration part 28b.
[0015]
4A and 4B are diagrams showing the case 21a to which the seal member 28 is attached, in which FIG. 4A is a perspective view and FIG. 4B is a cross-sectional view showing a groove portion in detail. The case 21a is formed in a substantially cylindrical shape, and a housing portion 211a of the seal 213, housing portions 211b and 211c of the bearing 212, a housing portion 211d of the resistor 214, and a housing portion 211e of the wiper 215 are formed therein. ing. The case 21a is formed with an O-ring groove 41 in which the O-ring portion 28a of the seal member 28 is disposed, and a groove 40 in which the cable penetration portion 28b and the cable 216 are disposed. The groove 40 is formed in the axial direction on the side surface of the case 21a and in the radial direction of the case 21a (the left-right direction in FIG. 4B) on the lower surface of the flange 218.
[0016]
The cable 216 is disposed along the groove 40 from the bottom portion of the case 21a, passes through the hole 28c of the cable penetration portion 28b, and is drawn upward. The gap between the cable 216 and the hole 28c is sealed with a molding material or the like. As described above, the resistor 214 and the like can be waterproofed by sealing with the seal member 28 and passing the cable 216 through the hole 28c of the seal member 28 and applying a molding material to the gap between the cable 216 and the hole 28c. .
[0017]
Further, instead of the sealing member 28 in which the O-ring portion 28a and the cable penetration portion 28b are integrally formed as shown in FIG. 3, a member 30 having a hole 30a through which the cable 216 passes as shown in FIG. It is good also as a structure which arrange | positions in case 21a and uses an O-ring as a sealing member on the outer side. FIG. 5B is a view showing a cross section of the member 30 attached to the case 21a. The case 21 a has the same shape as that shown in FIG. 4, and the member 30 is disposed in the groove 40. The member 30 is made of an elastic material such as rubber. The contact portion between the member 30 and the groove 40 is sealed by the surfaces 30c, 30d, and 30e, and the seal surface 30b with the O-ring has an arcuate cross section. The gap between the hole 30a and the cable 216 is sealed with a molding material or the like. The cross-sectional shape of the seal surface 30b may be a rectangle like a normal O-ring groove.
[0018]
FIG. 6 is a view showing another example of the case 21a, and a normal O-ring is used as a sealing member. 6A is a front view of the case 21a, FIG. 6B is a view of the case 21a as viewed from the bottom, and FIG. 6C is a cross-sectional view taken along the line CC in FIG. Each accommodating part 211a-211e formed inside case 21a is the same as that of case 21a shown in FIG. An axial groove 51 is formed at each of vertical positions sandwiching the O-ring groove 50, and a hole 52 that communicates with the upper and lower grooves 51 is formed so as to pass inside the O-ring groove 50. The upper groove 51 is formed not only on the side surface of the case 21a but also on the lower surface portion of the flange 218. The cable 216 is disposed from the lower groove 51 to the upper groove 51 through the hole 52 as indicated by a two-dot chain line, and after being pulled out from the flange 218, is connected to the controller 29 as shown in FIG.
[0019]
FIGS. 7A and 7B are diagrams for explaining another sealing method, in which FIG. 7A is a perspective view of a case 21a to which a sealing member is attached, and FIG. The case 21a is the same as that shown in FIG. 4. After the cable 216 is disposed in the groove 40, a portion of the groove 40 where the O-ring is applied is filled with a molding material 60 such as resin. By filling the molding material 60 in this manner, the lower portion of the figure (the portion where the sensor portion 21c such as the resistor 214 is disposed) is waterproofed than the O-ring.
[0020]
FIG. 8 is a view showing still another sealing method. In the sealing method shown in FIG. 8, a sealing member 80 (square ring) having a rectangular cross-sectional shape is attached around the main body 21 a, and the cable 216 passes through a hole 80 a formed in the sealing member 80. 8A is a view showing a seal structure of the case 21a housed in the recess 22a, and FIG. 8B is a sectional view taken along the line DD of FIG. 8A. In this case, the cable 216 drawn out from the bottom of the case 21a is disposed upward along the side surface of the case 216, and is taken out of the recess 22a through the radial groove 70 formed on the lower surface of the flange 218. . A gap between the hole 80a and the cable 216 is sealed with a molding material. In this example, it is necessary to provide a centering member (not shown) so that the axis of the input shaft 21 b does not deviate from the axis of the front pin 22.
[0021]
In the above-described embodiment, the angle sensor that detects the relative angle between the boom 3 and the arm 4 has been described. However, the boom angle that is the relative angle between the upper swing body 1 of the excavator and the boom 3, or the arm 4. This is also an angle sensor that detects a bucket angle, which is a relative angle between the bucket 5 and the bucket 5, or an angle sensor that detects an angle of a boom or jib of various cranes, an angle detection sensor of an articulated arm of an articulated work machine, or the like. The invention can be applied.
[0022]
In the correspondence between the embodiment described above and the elements of the claims, the arm 4 is the first member, the boom 3 is the second member, the front pin 22 is the connecting member, and the lever 23 is the transmitting member. Configure each.
[0023]
【The invention's effect】
As described above, according to the present invention, the case of the angle sensor is disposed in the recess provided in the connecting member, and the case is sealed by sealing between the case outer peripheral surface and the recess inner peripheral surface with the seal member. Since the inside of the recessed part accommodated is sealed, the waterproofness of an angle sensor can be improved easily. In addition, as in the second aspect of the invention, the cable portion can be reliably waterproofed by taking out the cable from the sensor portion to the outside through a hole provided in the seal member.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view for explaining an attachment state of an angle sensor in a working device according to the present invention.
FIG. 2 is a cross-sectional view showing details of the angle sensor 21 shown in FIG.
3A and 3B are diagrams showing details of a seal member 28, wherein FIG. 3A is a plan view and FIG. 3B is a cross-sectional view.
4A and 4B are diagrams showing a case 21a to which a seal member 28 is attached, in which FIG. 4A is a perspective view and FIG. 4B is a cross-sectional view showing a groove portion in detail.
5A and 5B are diagrams for explaining the member 30, in which FIG. 5A is a plan view of the member 30, and FIG. 5B is a cross-sectional view of the member 30 attached to the case 21a;
6A and 6B are diagrams showing another example of the case 21a, in which FIG. 6A is a front view, FIG. 6B is a view of the case 21a as viewed from the bottom, and FIG. .
7A and 7B are diagrams for explaining another sealing method, in which FIG. 7A is a perspective view of a case 21a fitted with a seal member, and FIG. 7B is a partial cross-sectional view showing a seal groove portion in detail.
8A and 8B are diagrams illustrating a seal member 80, in which FIG. 8A is a diagram illustrating a seal structure of a main body portion 21a accommodated in a recess 22a, and FIG. 8B is a cross-sectional view taken along line DD in FIG.
FIG. 9 is a diagram showing a schematic configuration of a hydraulic excavator.
[Explanation of symbols]
3 Boom 4 Arm 21 Angle sensor 21a Case 21b Input shaft 21c Sensor part 22 Front pin 22a Recess 23 Lever 28, 80 Seal member 218 Flange

Claims (2)

The rotation angle of the input shaft is set to a first member, a second member that is pivotally coupled to the first member via a coupling member that is integrally provided, and a case that is fixed to the coupling member. Construction comprising an angle sensor incorporating a sensor unit for detection, and a transmission member for connecting the first member and the input shaft so as to rotationally drive the input shaft in conjunction with the rotation of the first member. In machine working equipment,
(A) forming a recess in the axial end surface of the connecting member and disposing the case in the recess;
(B) A construction machine working apparatus comprising a seal member for sealing between the outer peripheral surface of the case and the inner peripheral surface of the recess to seal the inside of the recess. The working device according to claim 1,
A working device for a construction machine, wherein a hole penetrating in the axial direction of the input shaft is provided in the seal member, and a cable from the sensor unit is drawn out of the recess through the hole.

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