JPH0237871Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to an excavation depth detection device for a hydraulic excavator equipped with a backhoe type working machine.

Next, an example of a hydraulic excavator equipped with a conventional excavation depth detection device for a backhoe type work machine will be explained with reference to FIGS. 1 and 2.

A driver's cab 2 is installed at the front of the shovel body 1, and a boom 3, which is raised and lowered by a boom cylinder 4, is supported by a first pin (foot pin) 5. An arm 6 that is swung by an arm cylinder 7 is attached to a second pin 8 at the tip of the boom 3.
At the tip of the arm 6, a bucket cylinder 10 and a bucket 9, which is swung by a link, are supported by a third pin 11. A boom angle scale plate 12 is provided on the side of the boom 3.
is attached, and an arm angle scale plate 14 is attached to the side surface of the arm 6, and the scale plates 12, 1
Angle pointers 13 and 15 for detecting the angle relative to the ground are supported on rotating shafts 16 and 17, respectively.

In this hydraulic excavator, the angle of the boom 3 and arm 6 relative to the ground in any position of the work equipment is detected by the boom angle scale plate 12 and angle indicator needle 13, arm angle scale plate 14 and angle indicator needle 15,
Check the excavation depth using a numerical table of work machine angle vs. excavation depth prepared in advance. In such a detection means, in addition to the operator, angle indicator needles 13 and 15
A worker is required to read the angle indicated by
Moreover, if the arm 6 is submerged under the water surface, it becomes impossible to detect the excavation depth. Therefore, work efficiency is poor,
For example, accurate excavation work can only be performed up to a certain depth within a range where the arm angle scale plate 14 does not submerge in water.

The object of this invention is to provide a detection device that can easily confirm the excavation depth during operation and can detect the angle of the working machine even when the shovel body is tilted.

The excavation depth detection device of this invention has a boom supported by a first pin at the front of the shovel body, an arm connected to the tip of the boom by a second pin, and a third pin connected to the tip of the arm. In a hydraulic excavator that supports a bucket bucket, a first link with the first pin as a support link pin and a second link with the second pin as a support link pin are provided on the side of the boom. A common link is provided with a pin located between the pin and the second pin as a support link pin, and one end of the third link and the fourth link are connected by pins to the end of the opposite support link pin of the common link. , the other end of the third link is connected to the end of the first link next to the anti-support link pin by a pin, and the other end of the fourth link is fixed to the end of the fixed link near the connecting part of the arm. and connected to the end of the anti-support link pin of the second link by a pin, the first link;
The third link, common link, fourth link, and second link constitute two parallel link mechanisms, and a vertical maintenance weight is provided between the operator's cab on the excavator body and the boom, and the angle scale plate is concentric with the first pin. The boom indicator needle is rotatably supported by the boom, the arm indicator needle is provided integrally with the first link, and the boom indicator needle is fixed to the side of the boom so as to rotate together with the boom about the first pin. do.

The excavation depth detection device of this invention reads the angle indicated by the arm indicator needle and the boom indicator needle according to changes in the posture of the work equipment, and uses the angles indicated by the boom,
The excavation depth can be detected by applying the excavation depth to a numerical table calculated from the angle of the arm.

An example of this invention is shown below in Figures 3 and 4.
This will be explained using figures. In both figures, the same reference numerals as in FIG. 1 represent the same things.

On the side of the boom 3, there are a first pin 5 and a second pin 8.
with a support pin along the end, and a common link 1 in the middle.
Two parallel linkages are constructed with support link pins 19 forming 8. That is, the pin 2 is attached to the end of the common link 18 opposite to the support pin.
0 connects one end of the third link 21 and the fourth link 22, and the other end of the third link 21 is connected to the end of the first link 23 with the first pin 5 as a support pin by a pin 25. The other end of the four links 22 is connected by a pin 26 to the end of a second link 24 whose support pin is the second pin 8 and to the end of a fixed link 27 fixed near the connecting part of the arm 6. The pin 26 is supported at the end of the fixed link 27. The straight line connecting the first link 23, the third link 21, the common link 18, the first pin 5 and the support link pin 19 forms one parallelogram, and the second link 24, the fourth link 22, the common link 18 , the straight line connecting the support link pin 19 and the second pin 8 forms another parallelogram. In this embodiment, since the center line of the second link 24 is aligned with the extension of the straight line connecting the second pin 8 and the third pin 11, the center line of the first link 23 is aligned with the second pin 8. and the third pin 11.

Between the operator's cab 2 and the boom 3 on the shovel body 1, an angle scale plate 28 equipped with a vertical holding weight 28a is rotatably supported concentrically with the first pin 5. An arm indicator 29 and a boom indicator 30 are provided. The arm support needle 29 has a second pin 8 and a third pin 1.
The boom indicator needle 30 is located on the straight line connecting the second pin 8 and the first pin 5, and is provided integrally with the first link 23 with the first pin 5 as a support pin, parallel to the straight line connecting the second pin 8 and the first pin 5. It is fixed to the side surface of the boom 3 and rotates together with the boom 5 about the first pin 5. The angle scale plate 28 may be attached to the end of the first pin 5, or may be attached to the shovel body 1 concentrically with the first pin 5, and the indicator needles 29, 3
In order to read the 0 position, it is preferable to use a transparent material.

In the embodiment of this invention described above, as shown in FIG. Assuming that a portion of A is displaced to a position A' indicated by a chain line, the boom indicator needle 30 rotating around the first pin 5 is displaced to a position indicated by a chain line 30', and the arm indicator needle 29 is moved to a position indicated by a chain line 30'. The pin 26, which forms a parallel link as the
20, 19, 8 and 20, 19, 25 are at the dashed line positions 26', 20', 19', 8' and 20', 1
9' and 25', it moves to the position 29' indicated by the chain line. That is, the swinging of the arm indicator needle 29 and the boom indicator needle 30 is the same as the swinging of the arm 6 and boom 3. Therefore, the operator can confirm the angle indicated by the arm indicator needle 29 and the boom indicator needle 30 in any position of the working machine, which is read through the angle scale plate 28, while remaining in the operator's cab 2.
Since the X and Y coordinates of the first pin 5, the distance between the second pin 8 and the third pin 11, and the distance between the first pin 5 and the second pin 8 are known values, the angles of the boom 3 and arm 6 can be used for excavation. If you prepare a numerical table that calculates the depth (the depth from the ground surface of the crawler to the bottom of the bucket on the trajectory of the tip of the bucket), you can perform excavation work while checking the digging depth during operation. Because it can be done, it is efficient and economical.
In addition, since the angle scale plate 28 is a pendulum type, it can detect the angle relative to the ground, and even if the shovel body 1 is tilted, the angle of the work equipment can be detected regardless of that, so the detection function will not be affected in any way even in a work place on rough ground. .
In addition, since the X coordinate of the third pin 11, that is, the radius from the center of rotation of the shovel body, can be detected at the same time, when the shovel is used as a crane, the crane capacity at any working radius can be confirmed from the operator's cab. .

In the embodiment, in order to make this invention easier to understand, the center line of the second link 24 is provided on the extension of the straight line connecting the second pin 8 and the third pin 11, and the center line of the first link 23 is provided on the extension of the straight line connecting the second pin 8 and the third pin 11. Second pin 8 and third pin 11
However, if the two parallel link mechanisms described above are configured, the center line of the second link 24 is aligned with the second pin 8 and the third pin 11.
on the extension of the straight line connecting them, that is, the first link 2
It is not necessary to set the center line of 3 parallel to the straight line connecting the second pin 8 and the third pin 11.

Further, although the arm indicator needle 29 is arranged on an extension of the first link 23 and the center line, it is also provided integrally with the first link 23, for example, when the hydraulic excavator is installed on the horizontal ground, the second pin 8 and the third pin 11 The reference position may be the position of the arm indicator needle 29 when the straight line connecting these lines becomes perpendicular. Similarly, the boom indicator needle 30
is placed on the straight line connecting the first pin 5 and the second pin 8, but it does not need to be placed on the line if the first pin 5 is made concentric and rotates to follow the rotation of the boom 3. .

As explained above, according to this invention, the excavation depth of the work machine can be detected at all times, and work efficiency can be improved.

[Brief explanation of the drawing]

Fig. 1 is a side view showing an example of a hydraulic excavator equipped with a conventional backhoe-type excavation depth detection device, Fig. 2 is an enlarged side view showing the boom angle scale plate and angle indicator needle of Fig. 1; FIG. 3 is a side view showing an embodiment of this invention, and FIG. 4 is an enlarged explanatory view showing the parallel links in FIG. 3. 1... Shovel body, 2... Operator's cab, 3... Boom, 5... First pin, 6... Arm, 8... Second pin, 9... Bucket, 11... Third pin, 1
8...Common link, 19...Support link pin, 2
0...Pin, 21...Third link, 22...Fourth link, 23...First link, 24...Second link, 25...Pin, 26...Pin, 27...Fixed link, 28 ... Angle scale plate, 28a ... Vertical holding weight, 29 ... Arm indicator needle, 30 ... Boom support needle.

Claims (1)

[Scope of utility model registration request] In a hydraulic excavator, a boom is supported by a first pin at the front of the excavator body, an arm is connected to the tip of the boom by a second pin, and a backhoe type bucket is supported by a third pin at the tip of the arm. A first link in which the first pin serves as a support link pin and a second link in which the second pin serves as a support link pin are provided on the side of the boom, and a pin located between the first pin and the second pin serves as a support link. A common link is provided as a pin, one end of the third link and the fourth link are connected to the opposite end of the common link by a pin, and the other end of the third link is connected to the opposite end of the first link. The end of the fixed link connected to the end of the support link pin by a pin, and the other end of the fourth link fixed near the connection part of the arm, and the end of the second link opposite the support link pin. The first link, third link, common link, fourth link, and second link constitute two parallel link mechanisms, and are used for vertical maintenance between the operator's cab on the excavator body and the boom. An angle scale plate equipped with a weight is rotatably supported concentrically with the first pin, an arm indicator needle is provided integrally with the first link, and a boom indicator needle is configured to rotate together with the boom around the first pin. An excavation depth detection device for a working machine, characterized in that it is fixed to the side of a boom.