JPH0351696Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Application of the Invention] The present invention relates to an angle detection device that is attached to a connecting portion of two rotating bodies and detects a relative rotation angle of both rotating bodies.

[Background of the idea]

The boom and arm connection part that makes up the front of a hydraulic excavator, and the joint part of a robot's arm. Alternatively, in the contact area of each link of a link type crane, an angle detection device is installed at the connecting part of two rotating bodies that rotate relative to each other, and the relative rotation angle of both rotating bodies is detected. Various controls are performed based on the relative angle of the moving object.

Hereinafter, an angle detection device disposed at a connecting portion between a boom and an arm that constitutes the front of a hydraulic excavator will be described as an example.

FIG. 4 is a sectional view showing a first example of a conventionally known angle detection device of this type, and in this figure, 1 is a boom, 2 is an arm, and 3 is the boom 1.
4 is an angle detector provided on the surface of the boom 1; 5 is a connecting pin rotatably connecting the arm 2 and
is the rotation axis of the angle detector 4. Reference numeral 6 indicates the axis of the connecting pin 3, and the angle detector 4 is provided so that the axis of its rotating shaft 5 coincides with the axis 6. Here, a rotary encoder or the like is used as the angle detection device. 7 is a rotation transmission shaft disposed coaxially with the rotation axis 5 of the angle detector 4;
is a flexible joint that integrates this rotation transmission shaft 7 and the rotation shaft 5 of the angle detector 4. Reference numeral 9 denotes a rod erected on the arm 2, which is erected substantially parallel to the rotation shaft 5, and rotates integrally with the rotation of the arm 2. A transmission lever 10 transmits the rotational movement of the rod 9 to the rotating shaft 5, and one end is integrally connected to the distal end of the rod 9 by a nut 11. Reference numeral 12 denotes a joint to which the rotation transmission shaft 7 is provided and the transmission lever 10 is coupled.

In the above-mentioned angle detection device, when the arm 2 rotates about the connecting pin 3 with respect to the boom 1, the rod 9, the transmission lever 10, the joint 12, the rotation transmission shaft 7, and the flexible joint 8 rotate by the rotation angle. Then, the rotation axis 5 of the angle detector 4 fixed to the boom 1 is
The arm 2 rotates by the rotation angle relative to the boom 1. As a result, a signal corresponding to the amount of rotation of the rotary shaft 5 is output from the angle detector 4, and various controls such as excavation control of the hydraulic excavator can be performed based on this signal.

However, the angle detection device shown in FIG. 4 has the following drawbacks.

As shown in FIG. 4, a gap δ is provided between the boom 1 and the arm 2 to ensure smooth rotation between the boom 1 and the arm 2.
The arm 2 moves relative to the boom 1 in the illustrated y direction by this gap δ. In the conventional angle detection device described above, the arm 2 and the transmission lever are fixed via the rod 9, so that the arm 2
When the rod moves in this direction, an incorrect tensile or compressive force is applied to the rod 9, transmission lever 10, joint 12, flexible joint 8, and angle detector 4 depending on the amount of movement, which causes an error in the output signal. Otherwise, various parts of the device including the angle detector 4 may be damaged.

The axis 6 of the connecting pin 3 and the axis of the rotating shaft 5 of the angle detector 4 are strictly aligned in order to prevent improper force from acting on each part of the device and to prevent angle detection errors. However, the above-mentioned conventional angle detection device has
There is no means provided to precisely align the axes of the two, and it is difficult to achieve this with high precision. The deviation of the axes between the connecting pin 3 and the rotating shaft 5 can be absorbed to some extent by the flexible joint 8, but if the amount of deviation of the axes exceeds the allowable amount, the arm 2
With the rotation of the rod 9, the transmission lever 10,
Unauthorized forces may act on the joint 12, the rotation transmitting shaft 7, and the angle detector 4, resulting in errors in the output signal or damage to various parts of the device including the angle detector 4, which may cause problems.

Since the rotation shaft 5 of the angle detector 4 is mounted with the main body of the angle detector 4 inside facing the opposite side of the boom 1 and the arm 2, members such as the rod 9 and the transmission lever 10 are attached to the boom 1 and the arm 2. 2, and is easily damaged by colliding with external obstacles during use.

FIG. 5 is a sectional view showing a second example of a conventionally known angle detection device of this type. In this figure, the boom 1, arm 2, angle detector 4, rotating shaft 5, and flexible joint 8 are shown. , is the same as that shown in FIG. 13 is a connecting pin that rotatably connects the boom 1 and the arm 2; 14 is a transmission lever having one end fixed to the arm 2;
The tip of this transmission lever 14 is connected to the connecting pin 13.
The connecting pin 13 is fixed to the boom 1 as the arm 2 rotates.
Rotate by the relative rotation angle of . Reference numeral 15 denotes a housing, which is attached to the protruding end of the connecting pin 13 that protrudes outward from the boom 1 and the arm 2 so as to be slidable only in the circumferential direction of the connecting pin 13. 16
is an engagement pin that prevents the housing 15 and the connecting pin 13 from sliding in the y direction, and its tip end is fitted into a groove 17 formed in the circumferential surface of the connecting pin 13. 18 is a circle interposed between the housing 15 and the connecting pin 13. Reference numeral 19 denotes a fixture for the angle detector 4 fixed to the inner circumferential surface of the tip end of the housing 15, and a positioning part 4a formed on the protruding side of the rotating shaft of the angle detector 4 is fitted in the center part somewhat tightly. A through hole 20 is opened to The angle detector 4 is constructed by tightly fitting the positioning portion 4a into the through hole 20 from the outer surface of the fixture 19 and protruding the rotating shaft 5 toward the connecting pin 13. It is arranged at a position that coincides with the axis 21 of. 22 is a rotation transmission shaft that transmits the rotation of the connecting pin 13 to the rotation shaft 5 of the angle detector 4; 23 is a holding plate that holds this rotation transmission shaft 22; It penetrates the center of the plate 23 at right angles. This rotation transmission shaft 22 connects the connecting pin 1 with an end portion 22a protruding toward the back side of the holding plate 23.
Positioning hole 24 recessed in the center of the tip surface of 3
By fitting the holding plate 23 and the connecting pin 13 together with the bolts 25, the holding plate 23 and the connecting pin 13 are arranged on the axis 21 of the connecting pin 13. 26 is a bracket for fixing the housing 15 to the boom 1.

Such an angle detection device includes a locking pin 16 between a connecting pin 13 and a housing 15 that holds the angle detector 4.
The angle detector 4 is provided at the center of the housing 15 that is attached to the connecting pin 13 itself so that the axis 21 of the connecting pin 13 coincides with the axis 21 of the connecting pin 13. By setting , the axes of the connecting pin 13 and the angle detector 4 can be precisely aligned, and the rod 9 provided in the conventional example shown in FIG. 3 is omitted, and the arm 2 and the transmission lever are 14 close to each other, the above-mentioned drawbacks of the conventional example shown in FIG. 3 can be overcome.

However, on the other hand, since all related members are set on the connecting pin 13, the connecting pin 13
When replacing the bolts that connect the arm 2 and the connecting pin 13, the bolts that connect the boom 1 and the housing 15, the engagement pin 16 that engages the connecting pin 13 and the housing 15, and the retaining plate 23 and the connecting pin 13. The disadvantage is that the bolts to be fastened must be removed, making work extremely difficult. In addition, as the connecting pin 13 and the housing 15 are disassembled, the airtightness of the housing 15 in which the angle detector 4 is installed is lost, so foreign objects are likely to enter the angle detector 4, which may have an adverse effect on the angle detector 4. There is a risk of giving. Especially when this disassembly work is carried out at a civil engineering work site, sewage,
There is a disadvantage that foreign matter such as dust easily enters, and special consideration and equipment are required to prevent these foreign matter from entering the angle detector 4.

[Purpose of invention]

SUMMARY OF THE INVENTION An object of the present invention is to eliminate the drawbacks of the conventional angle detecting devices described above, and to provide an angle detecting device that allows easy positioning of the detector and has excellent workability, durability, and performance.

[Summary of the idea]

In order to achieve the above object, the present invention fixes the rotation axis of the angle detector and the rotation transmission shaft to a housing so that the rotation axis of the angle detector and the rotation transmission axis are located on the same axis. A positioning means having a pair of coaxially formed fitting parts is provided between the tip of the protruding rotation transmission shaft and a connecting pin that rotatably connects the first rotation body and the second rotation body. , a connecting means is provided between the second rotating body and the transmission lever for movably connecting the second rotating body to the transmission lever only in a direction parallel to the axis of the connecting pin. That is.

[Example of idea]

An embodiment of the present invention will be described below with reference to FIGS. 1 and 2.

FIG. 1 is a cross-sectional view showing the overall configuration of the angle detection device of the present invention, and FIG. 2 is a cross-sectional view taken along the line AA in FIG.

In these figures, the boom 1, arm 2, angle detector 4, and rod 9 are the same as those shown in FIGS. 4 and 5. Reference numeral 30 is a connecting pin between the boom 1 and the arm 2, and a groove 31 is formed in the circumferential surface of one end of the pin. 32 is formed. The connecting pin 30 is passed through the connecting portion of the boom 1 and the arm 2 from the groove 31 side, and is fixed to the connecting portion by fitting the locking piece 33 into the groove 31 protruding from the other end of the boom 1. be done. 34 is a housing fixed to the boom 1, which includes a detector mounting plate 35 and a rotation transmission shaft mounting plate 36.
are formed parallel to each other with a hollow portion 37 in between, and a detector mounting hole 38 is formed in this detector mounting plate 35.
and a rotation transmission shaft through hole 3 in the rotation transmission shaft mounting plate 36.
9 are installed on the same axis. The rotation shaft 5 of the angle detector 4 is configured by tightly fitting the positioning portion 4a of the angle detector 4 into the detector mounting hole 38.
It is arranged on the axis of the detector mounting hole 38. 4
0 is a rotation transmission shaft, and the rotation transmission shaft 40 is arranged on the axis of the rotation transmission shaft through hole 39 via a bearing 41. 42 is a flexible joint that connects the rotation shaft 5 of the angle detector 4 and the rotation transmission shaft 40; 43 is a cover attached to the housing 34;
4, 44a is the rotation transmission shaft through hole 3 of the housing 34.
9 and the rotation transmission shaft 40, and the housing 34.
This is a circle interposed between the cover 43 and the cover 43. 45 is a transmission lever, and the connecting portion 45
In a, a concave portion 46 into which the flange body 32 formed on the connecting pin 30 is fitted somewhat tightly, and a concave portion 47 into which the tip of the rotation transmission shaft 40 protruding from the housing 34 is fitted somewhat tightly. are formed coaxially. The transmission lever 45 is connected to the rotation transmission shaft 4 in the concave portion 47.
It is fixed to the rotation transmitting shaft 40 by fitting the tip of the screw 48 and screwing the screw 48. Reference numeral 49 is a through hole of the rod 9 opened at the other end side of the transmission lever 45, and is formed to have a diameter sufficiently larger than the diameter of the rod 9. 50 is a spring, and as shown in FIG. 2, a winding portion 50a formed in the center is fixed on a spring hook 51 erected on the transmission lever 45, and one end 50b of this spring is fixed.
is engaged with the side surface of the transmission lever 45, and the other end 50c is engaged with the rod 9 passed through the rod through hole 49, so that the transmission lever 45 and the rod 9 are always abutted in a constant positional relationship. I have to.

Next, the operation of the angle detection device of this embodiment will be explained.

When the arm 2 rotates about the connecting pin 30 with respect to the boom 1, the rod 9 and the transmission lever 4
5 also rotates around the connecting pin 30 together with this. The rotation of this transmission lever 45 is caused by the rotation transmission shaft 4
0 is transmitted to the rotating shaft 5 of the angle detector 4 via the flexible joint 42, and the rotating shaft 5 is connected to the boom 1 and the arm 2.
Rotate by the relative rotation angle of . This allows the angle detector 4 to output a signal proportional to this rotation angle. In this case, the connecting pin 30 and the rotation transmission shaft 40 are arranged such that the flange 32 formed at one end of the connection pin 30 and the tip of the rotation transmission shaft 40 are inserted into the concave portions 46 and 47 formed in the transmission lever 45. By fitting, they are set on the same axis, and since the rotation transmission shaft 40 and the rotation axis 5 of the angle detector 4 are set on the same axis on the housing 34, the axis of the rotation shaft 5 The center is precisely aligned with the axis of the connecting pin 30. Furthermore, since the rod through hole 49 through which the rod 9 is inserted is formed to be sufficiently larger than the diameter of the rod 9, even if the boom 1 and the arm 2 move relative to each other in the y direction shown in the figure, the transmission lever 45 will not move. Only the frictional force based on the pressing force of the spring 50 is applied, and the transmission lever 45, the rotation transmission shaft 40,
No illegal force is applied to the flexible joint 42 or the angle detector 4. On the other hand, since the spring 50 is stretched between the rod 9 and the transmission lever 45, the rod 9
The transmission lever 40 and the transmission lever 40 are always abutted against each other in a constant positional relationship, and even when the arm 2 rotates in the normal direction with respect to the boom 1, and even when the arm 2 rotates in the reverse direction, an error will not occur in the output signal of the angle detector 4. do not have.

In addition, in the above embodiment, as a positioning means for aligning the axial center of the connecting pin 30 with the axial center of the rotation transmission shaft 40, a positioning means is formed at the distal end of the connecting pin 30 in the connecting portion 45a of the transmission lever 45. A concave part 46 into which the collar body 32 of the connecting pin 30 is fitted, and a concave part 47 into which the tip of the rotation transmission shaft 40 is fitted are coaxially formed, and the collar body 32 of the connecting pin 30 is fitted into the concave parts 46 and 47, respectively. The main point of the present invention is to form a pair of fitting parts coaxially between the two members to be connected, and to connect the fitting parts to the top end of the rotation transmission shaft 40. This is characterized in that the two are positioned by fitting, and is not limited to the above embodiment. For example, as shown in FIG. 3, a positioning protrusion 52 is provided protrudingly at the center of the tip of the rotation transmission shaft 40, and this is fitted somewhat tightly into the center of the tip of the connecting pin 30 facing the positioning protrusion 52. It is also possible to provide a sufficient number of recessed portions 53 and arrange both of them coaxially.

Further, in the above embodiment, a rod 9 provided on the transmission lever 45 is provided as a connecting means for connecting the rod 9 erected on the arm 2 to the transmission lever 45 so as to be movable only in a direction parallel to the axial direction of the connecting pin 30. The rod 9 passes through the rod through hole 49, and the transmission lever 4
Spring 5 wound around spring hook 51 of 5
The spring 51 is wound around the rod 9, and both ends of the spring 51 are engaged with the transmission lever 45 and the rod 9, respectively. However, the gist of the present invention is not limited to this. It is also possible to engage the transmission lever 45 and the rod 9.

Further, in the above embodiment, only the angle detection device disposed at the joint between the boom and the arm that constitutes the front of the hydraulic excavator was described, but the application of the present invention is not limited to this, and is applicable to robots. It can be applied to various rotating bodies, such as arm joints and link connections of link cranes.

[Effect of idea]

As mentioned above, the angle detection device of the present invention has a first
A positioning means is provided between the connecting pin that connects the rotating body and the second rotating body and the rotating shaft of the angle detector to align the axes of both, so that the axes of both can be precisely aligned. This prevents any improper force from acting on the angle detector or other parts of the device due to the rotation of the first rotating body and the second rotating body.
Therefore, it is possible to prevent accidents such as damage to the angle detector due to this improper force, and to perform highly accurate angle detection.

Further, since a connecting means is provided between the second rotating body and the transmission lever to connect the second rotating body to the transmission lever so that the second rotating body can move only in a direction parallel to the axis of the connecting pin, Even if the first rotating body and the second rotating body move relative to each other within the range of the gap δ formed between the first rotating body and the second rotating body, the transmission lever, the flexible joint, the angle Unauthorized force will not be applied to the detector etc. Therefore, it has excellent durability and can perform highly accurate angle detection.

Furthermore, when replacing the first rotating body, the second rotating body, or the connecting pin, loosen the bolts that fix the housing to the first rotating body and the bolts that fix the locking piece of the connecting pin. Since the connecting pin can be pulled out with just one step, work efficiency can be greatly improved. In addition, even during these disassembly operations, the angle detector is sealed within the housing, so foreign matter such as dust will not enter the angle detector without the need for special dust prevention equipment as in the past.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing an embodiment of the angle detection device according to the present invention, FIG. 2 is a sectional view taken along line A-A in FIG.
Fig. 3 is a sectional view showing another embodiment of the angle detection device according to the present invention, Fig. 4 is a sectional view showing an example of the conventional angle detection device, and Fig. 5 is another example of the conventional angle detection device. FIG. 1: Boom, 2: Arm, 4: Angle detector,
5: Rotating shaft, 6: Axial center, 9: Rod, 30: Connecting pin, 31: Concave groove, 32: Flange body, 33: Locking piece,
34: Housing, 35: Detector mounting plate, 36: Rotation transmission shaft mounting plate, 37: Hollow part, 38: Detector mounting hole, 39: Rotation transmission shaft through hole, 40: Rotation transmission shaft, 41: Bearing, 42: Flexible joint, 4
3: Cover, 44: ○-ring, 45: Transmission lever, 46, 47: Recessed part, 48: Screw, 49: Rod through hole, 50: Spring, 51: Spring hook, 52: Button, 53: concavity.

Claims (1)

[Claims for Utility Model Registration] 1. A first rotating body and a second rotating body that are rotatably connected to each other using a connecting pin; an angle detector that detects a relative rotation angle between the rotating body and the second rotating body; a transmission lever connected to the second rotating body; In an angle detection device including a rotation transmission shaft that transmits data to a rotation shaft provided in a detector, the angle detection is performed such that the rotation axis of the angle detector and the rotation transmission shaft are coaxially located. a positioning means in which the rotation transmitting shaft is fixed to a housing, and a pair of fitting portions are coaxially formed between the tip of the rotation transmitting shaft protruding from the housing and the connecting pin. and connecting means for connecting the second rotating body to the transmission lever so as to be movable only in a direction parallel to the axis of the connecting pin, between the second rotating body and the transmission lever. An angle detection device characterized by being provided. 2. Utility model registration Claim 1, wherein the means for positioning the distal end of the rotation transmission shaft and the connecting pin includes a recessed portion sufficient to fit the distal end of the rotation transmission shaft somewhat tightly; An angle detection device characterized in that the transmission lever is coaxially provided with a concave portion sufficient to fit the tip of the connecting pin somewhat tightly. 3 Utility model registration In claim 1, the means for positioning the distal end of the rotation transmission shaft and the connecting pin comprises a protrusion protruding from the center of the distal end of the rotation transmission shaft and the connecting pin. An angle detection device, characterized in that the recess is provided in the center of the tip and is sufficient to fit the protrusion somewhat tightly. 4. In claim 1 of the utility model registration claim, the means for positioning the tip of the rotation transmission shaft and the connection pin comprises a protrusion protruding from the center of the tip of the connection pin, and a projection of the rotation transmission shaft. An angle detection device, characterized in that the recess is provided in the center of the tip and is sufficient to fit the protrusion somewhat tightly. 5 Utility model registration Claim 1, wherein the means for connecting the second rotating body and the transmission lever includes a rod that is erected on the second rotating body;
It is composed of a transmission lever having a rod insertion hole having a diameter larger than the diameter of the rod, and an elastic body stretched between the transmission lever and the rod inserted into the rod insertion hole. An angle detection device featuring: