JPH1151628A - Height measuring instrument for industrial machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a height measuring device for industrial machine which can measure the height position of the base-side end of the bucket of a power shovel with a simple constitution. SOLUTION: A liquid-pressure pipe 20 filled in with silicone oil is provided so as to connect the front end and base-side end of the height adjusting mechanism 124 (a boom 106 and an arm 108) of a power shovel 100 to each other. When the pipe 20 is provided, one end of the pipe 20 is constituted as a closed end by connecting the end to a liquid-pressure sensor unit 18 and the other end is constituted as an opened end opened to the atmospheric pressure by connecting the end to a tank 16. Then the liquid pressure in the pipe 20 is detected by means of the sensor chip of the sensor unit 18. Therefore, the height difference (h) between the liquid level in the tank 16 and the sensor chip can be measured directly.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a height measuring device for industrial machines, that is, a device for measuring a height position of a tip end of the height adjusting mechanism in an industrial machine having a height adjusting mechanism. It is.

[0002]

2. Description of the Related Art Many industrial machines are provided with a height adjusting mechanism, such as cranes, aerial work vehicles, and ladder vehicles. In such industrial machines, it is often convenient to know the height position of the tip of the height adjustment mechanism.
For example, if the height position of the tip of the height adjustment mechanism is known in the aerial work vehicle, it is possible to perform wiring at a desired height during the wiring work by the aerial work vehicle.

In industrial machines such as power shovels and bulldozers, buckets, blades, and the like are rotatably connected to the machine body via booms, arms, push arms, and the like. A push arm or the like functions as a kind of height adjustment mechanism. In this type of industrial machine, it is often convenient to know the height position of the tip of the height adjustment mechanism. For example, in the case of power shovels, it is often required to maintain a constant excavation depth from the viewpoint of preventing damage to underground pipes. In such a case, if the height position of the bucket is known, excavation is performed. Work can be performed easily.

For this reason, conventionally, with respect to a power shovel, a device for measuring a height position of a bucket has been devised as follows.

That is, a stake (a thread stretched horizontally) is applied in advance to a position near the excavation surface, and during excavation work, an operator of a power shovel first places a bucket on the stake. And lightly abut on it to set the reference position in this state. In this reference position setting operation,
Front-rear tilt angle sensor and left-right tilt angle sensor provided on the power shovel body, boom angle sensor provided on a joint between the power shovel body and the boom, arm angle sensor provided on a joint between the boom and the arm , And reset the rotation angle position data of the bucket angle sensor provided in the bucket rotation hydraulic cylinder.
During the excavation work, the amount of rotation of the boom, the arm, and the bucket from the reference position is detected by the five angle sensors, and a geometric calculation is performed based on the detection result. The position is measured.

[0006]

However, in such a conventional bucket height position measuring method, two tilt angle sensors are provided on the power shovel body and angle sensors are provided for each of the boom, arm and bucket. And an arithmetic unit for performing arithmetic processing based on the detection result is also required. In addition, the height position data obtained in this manner has a problem that accuracy is lacking because detection errors of the angle sensors are accumulated.

[0007] Such a problem can occur in industrial machines other than power shovels when the height position of the tip of the height adjusting mechanism is to be measured.

The present invention has been made in view of such circumstances, and a height for an industrial machine capable of accurately measuring the height position of the tip of the height adjustment mechanism with a simple configuration. It is an object of the present invention to provide a position measuring device.

[0009]

According to the present invention, the above object is achieved by utilizing a hydraulic pressure as a state quantity for detecting a height position.

That is, an industrial machine height position measuring apparatus according to the present invention is an industrial machine provided with a height adjusting mechanism. An apparatus for measuring a position, wherein a hydraulic pipe filled with a liquid therein is provided so as to communicate a distal end portion and a proximal end portion of the height adjustment mechanism, and one end of the hydraulic pressure pipe is provided. The liquid pressure pipe is configured as a closed end, and the other end of the hydraulic pipe is configured as an open end that is opened to the atmospheric pressure. A pressure sensor is provided.

The "industrial machine" is not limited to a specific machine as long as it is a machine used in the industrial world, but includes machines in various fields such as construction machines, machine tools, and vehicles.

The above-mentioned "height adjustment mechanism" may or may not be adjusted with respect to other directions as long as the mechanism can adjust at least the component in the height direction. It may be.

The type of the "liquid" is not particularly limited, and for example, silicon oil, water, antifreeze, alcohol and the like can be used.

The "one end" of the hydraulic pipe may be located on either side of the distal end and the proximal end of the height adjusting mechanism. However, if the “one end” is located at a position that is too high with respect to the “other end”, the inside of the hydraulic pipe is evacuated at the “one end” so that it becomes impossible to perform hydraulic pressure detection. In the case of an industrial machine (e.g., a power shovel) in which the distal end of the height adjusting mechanism is often located below the base end, the "one end" is connected to the distal end of the height adjusting mechanism. On the other hand, in the case of an industrial machine (for example, an aerial work vehicle, etc.) in which the distal end of the height adjustment mechanism is often located above the base end, the above-mentioned “one end” Is preferably located on the base end side of the height adjusting mechanism.

The "hydraulic pressure sensor" is not limited to a specific sensor as long as it can detect the hydraulic pressure in the hydraulic pressure pipe. For example, a strain gauge, a semiconductor pressure sensor, etc. Etc. can be adopted.

[0016]

As described above, according to the present invention, a hydraulic pipe filled with a liquid therein is provided so as to connect the distal end portion and the proximal end portion of the height adjusting mechanism. In addition, one end of the hydraulic pipe is configured as a closed end, and the other end of the hydraulic pipe is configured as an open end that is opened to the atmospheric pressure. Since the hydraulic pressure sensor for detecting the hydraulic pressure in the hydraulic piping is provided, the following operation and effect can be obtained.

That is, the hydraulic pressure detected by the hydraulic pressure sensor is equal to the height difference between one end and the other end of the hydraulic pipe,
That is, a value corresponding to the height difference between the distal end side and the proximal end side of the height adjusting mechanism is obtained. Therefore, by reading the detected hydraulic pressure, the height position of the tip of the height adjustment mechanism can be directly measured. Moreover, such an operation and effect can be obtained with an extremely simple configuration in which only the hydraulic pipe is provided so as to connect the distal end portion and the proximal end portion of the height adjusting mechanism.

Since one end of the hydraulic pipe is formed as a closed end, even if the hydraulic pipe is arranged so that its middle part is higher than the other end, Also, the liquid in the hydraulic pipe does not flow out from the open end of the other end, and does not adversely affect the hydraulic pressure detection accuracy of the hydraulic pressure sensor.

As described above, according to the present invention, the height position of the tip of the height adjusting mechanism can be accurately measured with a simple configuration.

The height measuring device for industrial machines according to the present invention can of course be incorporated in an industrial machine in an industrial machine manufacturing line, but has a very simple configuration as described above. It can be easily mounted on industrial machines.

According to a second aspect of the present invention, in addition to the above configuration, if a configuration is provided that includes a detection result notifying unit for notifying the detection result of the hydraulic pressure sensor, the operator can perform an operation in accordance with the content of the notification. By doing so, more accurate work can be performed.

Here, the "detection result notifying means" is not limited to a specific type of notifying means as long as it can appeal to the senses of the operator or the like. Display, when the height position exceeds a predetermined set value, or when it enters a preset area, the fact is displayed by a pilot lamp, or in place of these displays or In addition to these displays, a device that emits an alarm sound or gives vibration can be used.

According to a third aspect of the present invention, in addition to the above-mentioned configuration, a configuration is provided in which operation limiting means for limiting the operation of the height adjusting mechanism based on the detection result of the hydraulic pressure sensor is provided. With this operation restricting means, it is possible to prevent the height adjustment mechanism from inadvertently operating and impairing the work accuracy.

As described above, the type of the industrial machine is not particularly limited. However, when the industrial machine is a power shovel, the height adjustment mechanism is provided. Is an articulated mechanism, and
Since it is important to accurately measure the height position of the distal end portion of the height adjusting mechanism in order to smoothly perform the operation, it is particularly effective to employ the configuration of the present invention.

[0025]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is an overall configuration diagram showing an industrial machine height measuring apparatus according to an embodiment of the present invention, and FIG.
It is a side view which shows the power shovel (industrial machine) in which this height measuring device was mounted.

As shown in FIG. 1, a height measuring device 10 for an industrial machine according to this embodiment comprises a hydraulic piping unit 12 and
And a monitor unit 14.

First, the hydraulic piping unit 12 will be described.

The hydraulic piping unit 12 includes a tank 16
And a hydraulic pressure sensor unit 18, and a hydraulic pressure pipe 20 connecting the tank 16 and the hydraulic pressure sensor unit 18.

The tank 16 includes a tank body 16A,
The tank body 16A has a cap 16B which is screwed with the upper end opening 16Aa. An air communication passage 16Ab is formed in the upper end opening 16Aa of the tank body 16A, so that even when the cap 16B is screwed into the tank body 16A, the atmosphere communication passage 16Ab is formed through the air communication passage 16Ab. Atmospheric pressure can be introduced into the tank 16.

The hydraulic pipe 20 has an end (one end) on the hydraulic pressure sensor unit 18 side as a closed end (this will be described later) and the tank 1 thereof.
The end (the other end) on the sixth side is configured as an open end that is open to the atmospheric pressure as described above. The inside of the hydraulic pipe 20 is filled with silicone oil S. This silicon oil S is supplied to the liquid level W inside the tank 16.
L is formed.

The hydraulic pressure sensor unit 18 includes a hydraulic pressure sensor 22, a drain cock 24, and a cylindrical casing 26 for accommodating them. The hydraulic pressure sensor 22 is fixed at one end to the casing 26 via a T-tube 28, and the T-tube 28 is connected to an elbow pipe 30 outside the casing 26, Further, the hydraulic pipe 20 is connected to the elbow pipe 30. Thus, the silicon oil S in the hydraulic pipe 20 is introduced into the hydraulic sensor 22.

The other end of the T-tube 28 is connected to the drain cock 24. By turning the lever 24a of the drain cock 24, the silicon oil S in the hydraulic pipe 20 is drained by the drain pipe 32.
It is configured to be discharged to the outside of the casing 26 through (only a part is shown).

A cord 34 is connected to the other end of the hydraulic pressure sensor 22. The cord 34 extends to the outside of the casing 26 via a bushing 36.

FIG. 3 is a sectional perspective view showing a main part of the hydraulic pressure sensor 22. As shown in FIG.

As shown in FIG.
Is composed of a semiconductor pressure sensor utilizing the piezo effect.

That is, the hydraulic pressure sensor 22 includes a sensor chip 42 via a pedestal 40 on a header 38 that separates a hydraulic chamber in which the hydraulic pressure of the silicon oil S acts and an atmospheric pressure chamber in which the atmospheric pressure acts. It has been attached. The sensor chip 42 is formed by forming four bridge-connected diffusion resistors 46 and a pair of electrode films 48 on a silicon substrate 44 having a pressure-receiving diaphragm structure. It is connected to the lead pin 52 via the same. The pair of lead pins 52 is connected to the cord 34.

The sensor chip 42 receives the liquid pressure of the silicon oil S from the front side, and the atmospheric pressure from the back side through the air introduction holes 38a, 40a formed in the header 38 and the base 40. Is to receive. Therefore, the sensor chip 42 is bent and deformed from the state shown by the two-dot chain line in FIG. 4 to the state shown by the solid line in accordance with the magnitude of the hydraulic pressure of the silicone oil S. Due to this bending deformation, distortion occurs in the four diffusion resistors 46, and the resistance values change due to the piezo effect. Since the four diffused resistors 46 are bridge-connected,
The bending deformation appears as a voltage change between the pair of electrode films 48. That is, the hydraulic pressure of the silicon oil S is detected as a voltage value.

The hydraulic pressure of the silicone oil S detected by the hydraulic pressure sensor 22 is
Since the pressure is generated by the height difference h between the liquid level WL in 6 and the sensor chip 42, the voltage output as the detected hydraulic pressure of the silicon oil S corresponds to the height difference h. This output voltage is input to the monitor unit 14 via the cord 34. Although the height difference h and the output voltage do not strictly have a linear relationship, as shown in FIG. 5, the height difference h and the output voltage when the height difference h is set to 10 m in full scale. Is substantially linear (even with a maximum error of 0.5% or less).

In order to accurately measure the height difference h by the hydraulic pressure sensor unit 18, it is important that no bubbles or the like exist inside the hydraulic pressure pipe 20. To realize this, the drain cock 2
By rotating the lever 24a of No. 4 to discharge the silicon oil S in the hydraulic pipe 20, the silicon oil S may be continuously supplied into the tank body 16A of the tank 16 for a predetermined time.

Next, the monitor unit 14 will be described.

As shown in FIG. 1, the monitor unit 1
Reference numeral 4 denotes a unit for notifying the detection result of the hydraulic pressure sensor 22, which includes a monitor panel 54, a power cord 56 for connecting the monitor panel 54 to a DC power supply (24V battery power supply), The cord 34 extends from the cable 22 and is connected to the monitor panel 54.

The monitor panel 54 includes a panel body 58
In addition, a reset button 60, a height display section 62, pilot lamps 64 and 66, setting display sections 68 and 70, and a speaker 72 are provided.

The reset button 60 is a button for resetting various notification contents on the monitor panel 54 and setting a notification reference state. The height display section 6
Numeral 2 digitally displays a value obtained by converting the output voltage of the hydraulic pressure sensor 22 into the height difference h. The pilot lamp 64 is a green lamp that is turned on when the height difference h reaches a first set value, and the pilot lamp 66 is turned on when the height difference h reaches a second set value. Red lamp. The setting display section 6
Numerals 8 and 70 display the first and second set values. These first and second setting values are set by operating buttons 68a, 68b and 70a, 70b provided on the right side of the setting display sections 68 and 70. The above speaker 72
Emits a notification sound when the height difference h reaches a first set value, and emits an alarm sound when the height difference h reaches a second set value. It has become.

As shown in FIG. 1, the hydraulic piping 20 and the cord 34 have flexibility, and the portions other than both ends of the hydraulic piping 20 and the cord 34 have flexibility. It is covered by a protection tube 74.

Next, the height measuring device 10 according to this embodiment
A power shovel equipped with is described.

As shown in FIG. 2, this power shovel 1
Reference numeral 00 denotes a general power shovel in which a boom 106, an arm 108, and a bucket 110 are sequentially connected to a cab 104 rotatably provided on an endless track 102. The boom 106, the arm 108, and the bucket 1
10 are hydraulic cylinders 112, 114 and 116, respectively.
By the operation of, the joint shafts 118, 120 and 122 are vertically rotated about respective axes thereof. In the power shovel 100, the boom 106,
Arm 108 and hydraulic cylinders 112 and 114
However, a height adjustment mechanism 124 that adjusts the height of the bucket 110 with respect to the cab 104 is configured.

The height measuring device 10 is mounted on the power shovel 100 as follows.

That is, the hydraulic pressure sensor unit 18 of the height measuring device 10 is provided on a joint shaft 122 between the arm 108 and the bucket 110. At this time, the hydraulic pressure sensor unit 18 is provided such that the cylindrical casing 26 is accommodated in the cylindrical space of the joint shaft 112. The tank 16 and the monitor panel 54 of the height measuring device 10 are provided in the cockpit 126 of the cab 104. At this time, the monitor panel 54 is arranged at a place where the operator can easily see it. Further, the height measuring device 10
The hydraulic pipe 20 and the cord 34 are covered with the protection tube 74, and the boom 106 and the arm 1 are
08.

Next, the operation of the present embodiment will be described.

In FIG. 2, the power shovel 100
However, it is assumed that a trench having a depth D (for example, D = 3 m) from the siding R is excavated. At this time, if the operator can know the height position of the tip of the bucket 110,
It becomes possible to excavate the groove at the depth D accurately.

In such a case, the excavation depth can be measured by the height measuring device 10 as follows.

First, as shown by a two-dot chain line in FIG. 2, the bucket 110 is set in substantially the same posture as when excavating, and its tip is lightly abutted against the stub R. In this state, the monitor panel 54 is reset. Pressing the button 60 resets various notification contents. At this time, the hydraulic pressure sensor unit 18
Although the liquid pressure according to the height difference h between the liquid level WL in the tank 16 and the sensor chip 42 is being detected,
The detected value is adjusted to zero by the reset operation.
In addition, when the ground surface G is leveled on a flat surface, the tip of the bucket 110 may abut on the ground surface G instead of abutting on the stake R.
In such a case, the ground surface G serves as a reference for the excavation depth, so that the towing R is not required.

When the bucket 110 is lowered for excavation work, the lowered amount is displayed on the height display section 62. When the bucket 110 descends and the tip approaches the depth D with the progress of the excavation work, the pilot lamp 64 is turned on when the depth D ′ becomes slightly smaller than the depth D (for example, D ′ = 2.7 m). Lights green and emits a notification sound to notify that the speaker 72 has approached the depth D.

When the tip of the bucket 110 reaches the depth D by further lowering the bucket 110 to perform the excavation work, the pilot lamp 66 lights up in red and the speaker 72 notifies that the depth has reached the depth D. Emit an audible alarm.

The values of the depths D 'and D are set by the setting display sections 68 and 70 to the first and second values.
Is set and displayed in advance as the set value of.

The operator operates the pilot lamp 64
Excavation work is performed without paying special attention to the excavation depth until the green light is turned on or the speaker 72 emits an alarm sound. When the excavation work is performed so that the pilot lamp 66 lights up in red or the speaker 72 emits an alarm sound so that the depth does not exceed the depth, the groove can be approximately accurately set at the depth D. Can be drilled.

As described in detail above, in the present embodiment, the hydraulic pipe 20 filled with the silicon oil S is used.
Is provided so as to connect the distal end portion and the proximal end portion of the height adjusting mechanism 124 of the power shovel 100, and one end of the hydraulic pressure pipe 20 is connected to the hydraulic pressure sensor 22. The other end of the hydraulic pipe 20 is connected to the tank 16 and is configured as an open end that is opened to the atmospheric pressure, and the hydraulic pressure sensor 22 detects the hydraulic pressure. Since the liquid pressure in the pipe 20 is detected, the liquid pressure sensor 22 detects the liquid level WL in the tank 16 and the sensor chip 4.
2 can be directly measured, and thereby the height position of the tip of the height adjustment mechanism 124 can be measured directly.

Further, such an operation and effect can be obtained with a very simple configuration in which the hydraulic pipe 20 is provided so as to connect the distal end portion and the proximal end portion of the height adjusting mechanism 124. .

As described above, according to the present embodiment, the height position of the tip of the height adjusting mechanism 124 can be accurately measured with a simple configuration.

In order to accurately measure the excavation depth of the excavator 100, it is necessary to consider the height between the base end (ie, the joint shaft 122) and the tip of the bucket 110. Regarding this point, as described above, the reset button 60 of the monitor panel 54 is pressed by pressing the reset button 60 of the monitor panel 54 with the bucket 110 in the substantially same posture as that at the time of excavation and the tip thereof lightly abutting on the stake R. By resetting the contents, the excavation depth can be measured in consideration of the height between the base end (i.e., the joint shaft 122) and the front end of the bucket 110. In this case, the excavation posture of the bucket 110 has a different inclination angle depending on the nature of the excavated ground, etc.
It is desirable that the reset operation be performed every time the excavation work is performed.

In this embodiment, since the pilot lamps 64 and 66 for visually informing the detection result of the hydraulic pressure sensor 22 and the speaker 72 for informing audibly are provided, the operator can be notified of the contents of the notification. , The digging operation can be performed at a substantially accurate digging depth even if the digging depth is not so nervous.

Note that, as shown in FIG.
0 is the tank 16 at the boom 106.
Although it is arranged at a position higher than the liquid level WL in the inside, since the end of the hydraulic pressure pipe 20 on the side of the hydraulic pressure sensor unit 18 is configured as a closed end, the inside of the hydraulic pressure pipe 20 is The silicon oil S does not overflow from the tank 16 and does not adversely affect the hydraulic pressure detection accuracy of the hydraulic pressure sensor 22.

In the present embodiment, the casing 26 of the hydraulic pressure sensor unit 18 is formed in a cylindrical shape, and the casing 26 is connected to the joint shaft 1 between the arm 108 and the bucket 110.
The liquid pressure sensor unit 18 is provided on the joint shaft 122 by being accommodated in the cylindrical space 12.
A bracket (not shown) may be fixed to the end of the casing 12, and the casing 26 may be attached to the bracket. In this case, the bracket can be fixed to the joint shaft 112 by fastening the bracket together with a bolt used for connecting the arm 108 and the bucket 110 at the joint shaft 112. In this case, the casing 2
6 may be formed in a shape other than the cylindrical shape (for example, a rectangular parallelepiped).

Instead of the operator controlling the excavation depth in accordance with the notification of the detection result of the hydraulic pressure sensor 22 as in the present embodiment, the height adjusting mechanism 124 is controlled based on the detection result of the hydraulic pressure sensor 22. May be limited to the excavation depth range between the depths D 'and D. In this way, it is possible to prevent the height adjustment mechanism 124 from being carelessly operated and the accuracy of the excavation work from being impaired. In this case, the hydraulic cylinders 112, 114
The depths D 'and D are stored in advance in an operation control device (not shown) of the
Then, the detection result of the hydraulic pressure sensor 22 may be output to the operation control device.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram showing an industrial machine height measuring apparatus according to an embodiment of the present invention.

FIG. 2 is a side view showing a power shovel on which the height measuring device is mounted.

FIG. 3 is a sectional perspective view showing a main part of a liquid pressure sensor of the height measuring device.

FIG. 4 is a front view of a sensor chip showing an operation of the above-mentioned hydraulic pressure sensor.

FIG. 5 is a graph showing characteristics of the hydraulic pressure sensor.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Height measuring device for industrial machines 12 Hydraulic piping unit 14 Monitor unit 16 Tank 18 Hydraulic sensor unit 20 Hydraulic piping 22 Hydraulic pressure sensor 26 Casing 34 Code 42 Sensor chip 54 Monitor panel 56 Power cord 58 Panel body 60 Reset button 62 Height display part (detection result notifying means) 64, 66 Pilot lamp (detection result notifying means) 68, 70 Setting display part 72 Speaker 74 Protective tube 100 Power shovel (Industrial machine) 104 Driver's cab 106 Boom 108 Arm 110 Bucket 112 , 114, 116 Hydraulic cylinders 118, 120, 122 Articulated shaft 126 Pilot cabin h Height difference S Silicon oil WL Liquid level

Claims (4)

[Claims] 1. An industrial machine provided with a height adjusting mechanism, which is a device for measuring a height position of a tip portion of the height adjusting mechanism, wherein a hydraulic pipe filled with a liquid therein is provided with a hydraulic pipe. The hydraulic control device is provided so as to connect a distal end portion and a proximal end portion of the adjusting mechanism. One end of the hydraulic piping is configured as a closed end, and the other end of the hydraulic piping is open to the atmospheric pressure. A height measuring device for industrial machinery, wherein the height measuring device is configured as a closed end, and a hydraulic pressure sensor for detecting a hydraulic pressure in the hydraulic pressure pipe is provided at the one end. 2. The height measuring device for an industrial machine according to claim 1, further comprising detection result notifying means for notifying the detection result of the hydraulic pressure sensor. 3. The height for an industrial machine according to claim 1, further comprising an operation restricting means for restricting an operation of the height adjusting mechanism based on a detection result of the hydraulic pressure sensor. measuring device. 4. The industrial machine is a power shovel,
The height measuring device for industrial machines according to any one of claims 1 to 3, wherein