JPH04366236A - Inclination controller for construction equipment - Google Patents

Abstract

PURPOSE:To prevent the lift-up more than required of the whole structure section by detecting the actual inclination angular velocity of a construction equipment provided with a flow control means controlling the drive of a hydraulic boom actuator and actual inclination angular velocity and outputting a controlled variable to the flow control means on the basis of a deviation with a target inclination. CONSTITUTION:The inclination controller of a construction equipment having a flow control means 22 controlling the drive of a hydraulic boom actuator 7 is provided with an actual inclination angular velocity detecting means 18, an actual inclination detecting means 19 and a target inclination setting means 20. The deviation of an actual inclination detected during excavation and a target inclination and a command value to the pressure control valve 22 on the basis of an actual inclination angular velocity detected are arithmetically operated and the hydraulic actuator 7 is driven, and the boom is driven in the direction that jack-up is reduced on jack-up. Accordingly, even when the front end of working structure encounters a hard section and jack-up is generated, jack-up is prevented, and a shock due to falling can be obviated.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an inclination angle control device for a construction machine used for preventing excessive jacking up of a construction machine for excavation work.

0002

2. Description of the Related Art Construction machines such as hydraulic excavators are used for works such as excavating the ground and removing rocks. This hydraulic excavator will be explained with reference to the drawings. FIG. 5 is an external side view of the hydraulic excavator during excavation work. In general, hydraulic excavators are
Upper rotating body 3 having an operator room 2 on the lower traveling body 1
a main body structure on which is rotatably mounted, and an upper revolving body 3
A boom 4, an arm 5, and a bucket 6, which rotate vertically with one end as a fulcrum, are sequentially connected to the boom 4, an arm 5, and a bucket 6, and a boom hydraulic actuator 7, an arm hydraulic actuator 8,
The working mechanism section 10 includes a bucket hydraulic actuator 9. By appropriately driving the boom hydraulic actuator 7, the arm hydraulic actuator 8, and the bucket hydraulic actuator 9, the ground or the like is excavated with the bucket 6 as shown in the figure.

0003

[Problems to be Solved by the Invention] By the way, during excavation work using the hydraulic excavator, if the excavation reaction force becomes excessive due to various reasons such as the presence of rocks, the entire main body structure will collapse into the lower traveling body 1 as shown in FIG. There are cases where the vehicle is lifted up and tilted (jacked up) using one end as a fulcrum. In general, when the work mechanism section 10 performs excavation work, if the work mechanism section 10 is under the required pressing force against the excavated object, the excavation work can be performed efficiently. If the entire main body structure is lifted up by a predetermined amount or more due to the reaction force and becomes in the jacked-up state, no further pressing force can be generated and excavation efficiency will not improve. On the other hand, when the excavation is carried out as shown by the broken line in the jacked-up state shown in the figure and the excavation point reaches point A shown in Fig. 5, the excavation reaction force immediately disappears, so that the main body that was in the inclined state The entire structure falls to the ground due to gravity, but the impact of this fall is greater as the main structure rises higher. If such jacking up and dropping continues, various problems will occur, such as damage to the crawler tracks and failure of the electrical circuit system due to continuous impact on the electrical circuit system.

An object of the present invention is to solve the above-mentioned problems of the prior art, and to prevent the entire main body structure from lifting more than necessary while maintaining the pressing force of the working mechanism part necessary for obtaining high excavation efficiency in excavation work. An object of the present invention is to provide a tilt angle control device for a construction machine that can prevent the impact caused by the entire body structure falling to the ground.

[0005]

[Means for Solving the Problems] In order to achieve the above object, the present invention provides a main body structure, a boom attached to the main body structure, a boom hydraulic actuator for driving the boom, and a boom hydraulic actuator for driving the boom. An inclination angle control device for a construction machine including a working mechanism section having a flow rate control means for controlling the drive of an actuator, an actual inclination angular velocity detection means for detecting an actual inclination angular velocity of the main body structure; an actual inclination angle detection means for detecting an inclination angle; a target inclination angle setting means for determining a target value of the inclination angle of the main body structure; and an actual inclination angular velocity detected by the actual inclination angular velocity detection means and the actual inclination angle detection. and calculation control means for calculating and outputting a control amount for the flow rate control means based on both the deviation between the actual tilt angle detected by the means and the target tilt angle set by the target tilt angle setting means. It is characterized by

[0006]

[Operation] During excavation work, the calculation control means detects the deviation between the actual inclination angle detected by the actual inclination angle detection means and the target inclination angle set by the target inclination angle setting means, and the deviation detected by the actual inclination angular velocity detection means. A command value for the flow rate control means is calculated based on the actual inclination angular velocity, and the flow rate control means drives the boom hydraulic actuator in accordance with the command value. This causes the boom to be driven in a direction that reduces jacking up when jacking up.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be explained below based on the illustrated embodiments. FIG. 1 is a system diagram of a tilt angle control device for construction machinery according to an embodiment of the present invention. In the figure, 7 is the same boom hydraulic actuator as shown in FIG. 5, 11A is a hydraulic pump, 11B is a pilot circuit hydraulic pump, 12 is a relief valve, 13 is a pilot circuit relief valve, 14 is a boom hydraulic actuator 7 This is a flow control valve that controls the flow rate of pressure oil supplied to the pump and switches the flow direction of the pressure oil. Reference numerals 15 and 16 indicate operating valves operated by an operator, which selectively supply pressure oil to the pilot port of the flow control valve 14. Reference numeral 18 denotes an actual tilt angular velocity detection means, which is configured using, for example, an optical fiber laser gyro utilizing the Zagnac effect, and detects the tilt angular velocity of the main body structure. Reference numeral 19 denotes an actual inclination angle detection means, which is constructed using, for example, an inclination measuring device using a weight, and detects the inclination angle of the main body structure from the horizontal line. Reference numeral 20 denotes a target inclination angle setting command means, which is composed of, for example, an automatic return type switch that can be operated by an operator. Reference numeral 21 denotes an arithmetic control means, which is composed of a microcomputer, and is configured to control the actual inclination angular velocity detected by the actual inclination angular velocity detection means 18, the actual inclination angle detected by the actual inclination angle detection means 19, and the target inclination angle setting command means. The control amount of the pressure control valve, which will be described later, is calculated based on the target inclination angle commanded in step 20. A pressure control valve 22 generates pilot pressure according to a control command signal from the calculation control means 21. A shuttle valve 23 selects the higher pressure between the pressure from the pressure control valve 22 and the pressure from the operation valve 16.

FIG. 2 is a block diagram illustrating the functions of the calculation control means 21. 25 is a first coefficient unit that multiplies the actual tilt angular velocity signal θ' by a correction value K; 26 is a mixer 27 that applies a correction value to the deviation Δθ obtained as a result of subtracting the actual tilt angle θ from the target tilt angle signal θr; This is a second coefficient multiplier that multiplies Kp. A calculation system 28 calculates a command signal T to the pressure control valve 22 based on the signal S output from the mixer 29. The command signal T calculated by the calculation system 28 is a signal proportional to the added signal obtained as a result of adding the value based on the actual tilt angular velocity signal θ' and the value based on the deviation Δθ, or proportional to the square of the added signal. The added signal may be a signal with predetermined characteristics corresponding to the added signal. 30
is a control system including a pressure control valve 22, a shuttle valve 23, a flow rate control valve 14, and an actual inclination angle detection means 19, which drives the boom hydraulic actuator 7 based on the command signal T, and further controls the new The actual tilt angle signal θ is detected and fed back to the mixer 27.

FIG. 3 is a flowchart showing the operation of the calculation control means 21. The arithmetic control means 21 calculates the inclination angular velocity signal detected by the actual inclination angular velocity detection means 18, the inclination angle signal detected by the actual inclination angle detection means 19, and the target inclination set by the target inclination angle setting command means 20 during excavation. The angle setting command signal is read (step 301). Here, the reason for employing the actual tilt angular velocity signal and the actual tilt angle signal in this embodiment will be explained. During excavation, if the tip of the working mechanism section 10 suddenly encounters a hard part such as rock, jacking up occurs rapidly. By the way, for example, if only the actual inclination angle signal is used to prevent jack-up, no action will be taken to prevent jack-up unless the jack-up reaches the target inclination angle or more. Therefore, the working mechanism section 10 was damaged before measures were taken to prevent jacking.
When the tip reaches point A shown in FIG. 5, falling of the main body structure cannot be avoided. However, if the actual tilt angular velocity signal is used in addition to the actual tilt angle signal to prevent jacking up as in this embodiment, regardless of the jacking angle, measures to prevent jacking up can be taken based on the tilt angular velocity. Therefore, the working mechanism section 10
When the tip of the machine suddenly encounters a hard part of the ground, it is possible to predict that an excessive jack-up will occur and take prompt action. Next, it is determined whether the target inclination angle setting command signal is on or off (step 302). Here, if the target tilt angle setting command signal is on,
That is, when the operator closes the switch of the target inclination angle setting means 20, the actual inclination angle signal read this time is stored in a storage device (not shown), and a process is executed to use this as the target inclination angle signal ( Step 303). Next, a predetermined correction signal is added to the target tilt angle signal set in step 303, and the deviation between this added value and the actual tilt angle signal read this time is determined (step 304).
. Here, the correction signal is a value determined for the following reason. That is, when performing excavation work with a construction machine, when the excavation force is maximized, the main body structure is tilted by a very small angle (approximately 1° to 5°) compared to a non-excavating state. Therefore, if the jack-up is held down to 0, there is a risk that excavation efficiency will be impaired. Therefore,
The above-mentioned disadvantage is avoided by determining the above-mentioned angle as a correction signal and adding this to the target inclination angle signal. If there is a deviation (that is, in a jacked-up state), a command signal to the pressure control valve 22 is determined according to the deviation and the tilt angular velocity signal (step 305). By outputting the calculated command signal to the pressure control valve 46 (step 306), the pressure control valve 46 supplies pressure oil proportional to this command signal to the pilot port of the switching valve 34 via the shuttle valve 48. Output to
The boom hydraulic actuator 7 is driven to rotate the boom 14 vertically upward, lowering the main body structure and eliminating jack-up. On the other hand, if the operator turns off the target inclination angle setting means 42 in step 302, the already set target inclination angle is used as is, and the processes of steps 304, 305, and 306 are subsequently performed.

FIG. 4 is a flowchart showing the operation of another embodiment of the calculation control means 21. In this embodiment, the target inclination angle setting means 20 is not required, and the target inclination angle is automatically set. The calculation control means 21 is
First, the actual tilt angle signal from the actual tilt angle detection means 18 and the actual tilt angular velocity signal from the actual tilt angular velocity detection means 19 are read (step 401). Next, it is determined whether the difference between the actual tilt angle signal read this time and the actual tilt angle signal read a predetermined time ago is less than or equal to a predetermined value (step 402). If it is less than a predetermined value, that is, if the hydraulic excavator is not moving, a process is executed in which the read value of the actual inclination angle signal a predetermined time ago is used as the target inclination angle signal (
Step 403). Below, steps 404, 405, 4
The process of step 06 includes steps 304, 305, and 30 shown in FIG.
This is the same as the process in step 6. However, although addition of correction signals is not described, it is of course possible to add correction signals. On the other hand, in step 402, if it is determined that the difference between the actual inclination angle signal read this time and the actual inclination angle signal read a predetermined time ago is greater than or equal to a predetermined value, that is, if it is determined that the hydraulic excavator has moved. Step 4
The process of step 03 becomes unnecessary, and the process of step 404 and subsequent steps will be performed. In this case, the target inclination angle signal determined in step 403 last time is maintained as it is.

As described above, in this embodiment, the actual inclination angle signal and the actual inclination angular velocity signal are used, and the command signal to be output to the pressure control valve 22 is determined from the results of predetermined calculations. Excessive jacking up of the main body structure can occur in either case where the tip of the working mechanism section 10 suddenly encounters a hard part of the ground and jacking up occurs rapidly, or where jacking up occurs gradually. It is possible to prevent the impact caused by the fall of the device. In addition, in the description of the above embodiment, an example was explained in which the actual inclination angular velocity detection means 18 is used to obtain the actual inclination angular velocity.
It can also be obtained by detecting the actual inclination angle in step 9 and differentiating the detected value.

0012

According to the present invention, the actual inclination angular velocity detected by the actual inclination angular velocity detection means, the actual inclination angle detected by the actual inclination angle detection means, and the target inclination angle set by the target inclination angle setting means. The operation of the flow rate control means is appropriately controlled based on both the deviation from the In any case where the main body structure is lifted up, it is possible to reliably prevent the main body structure from being excessively jacked up, and furthermore to prevent the shock caused by the sudden fall of the main body structure to the ground.

[Brief explanation of drawings]

FIG. 1 is a block diagram of a tilt angle control device for construction machinery according to an embodiment of the present invention.

FIG. 2 is a schematic system diagram of the calculation control means of this embodiment.

FIG. 3 is a flowchart showing the operation of the arithmetic control means.

FIG. 4 is a flowchart showing the operation of another embodiment of the calculation control means.

FIG. 5 is an external side view of the hydraulic excavator during excavation work.

[Explanation of symbols]

7 Hydraulic actuator for boom 11A, 11B Hydraulic pump 14 Flow control valve 15, 16 Operation valve 18 Actual tilt angular velocity detection means 19 Actual inclination angle detection means 20 Target inclination angle setting means 21 Arithmetic control means 22 Pressure control valve 23 Shuttle valve

Claims (5)

[Claims] Claim 1: A work mechanism unit comprising a main body structure, a boom attached to the main body structure, a boom hydraulic actuator for driving the boom, and a flow rate control means for controlling the drive of the boom hydraulic actuator. In the inclination angle control device for construction machinery, an actual inclination angular velocity detection means for detecting an actual inclination angular velocity of the main body structure;
an actual inclination angle detection means for detecting an actual inclination angle of the main body structure; a target inclination angle setting means for determining a target value of the inclination angle of the main body structure; and an actual inclination angular velocity detected by the actual inclination angular velocity detection means. and a calculation for calculating and outputting a control amount for the flow rate control means based on both the deviation between the actual inclination angle detected by the actual inclination angle detection means and the target inclination angle set by the target inclination angle setting means. An inclination angle control device for construction machinery, characterized by comprising a control means. 2. The inclination angle control device for a construction machine according to claim 1, wherein the actual inclination angular velocity detection means comprises a gyro. 3. The inclination angle control device for a construction machine according to claim 1, wherein the actual inclination angular velocity detection means is a means for determining a differential value of the actual inclination angle obtained by the actual inclination angle detection means. . 4. The target inclination angle setting means includes target inclination angle setting command means for outputting a signal according to the operation amount;
2. The tilt angle control device for construction machinery according to claim 1, further comprising a storage means for storing the actual tilt angle signal from the target tilt angle setting command means. 5. The target inclination angle setting means sets the actual inclination angle signal as the target before the elapse of a predetermined time when the amount of change in the actual inclination angle signal within a predetermined time is less than or equal to a predetermined value. 2. The inclination angle control device for a construction machine according to claim 1, further comprising means for setting the inclination angle.