JP3462683B2 - Backhoe - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a boom cylinder for driving a boom by connecting a boom, an arm, and a bucket to a machine base in a series, and an arm cylinder for driving an arm. ,
A backhoe having a bucket cylinder for driving a bucket, each of which has a boom sensor for measuring a swing angle of a boom with respect to a machine base, and a backhoe with each of an arm sensor for measuring a swing angle of an arm with respect to the boom. The present invention relates to a technique for operating a tip of an arm in a vertical direction, for example, when performing an operation of lifting an object. 2. Description of the Related Art As described above, when the tip of a backhoe apparatus is operated in a vertical direction, an operator operates a boom and an arm separately, and the operator visually positions the tip of the arm. The amount of operation between the boom and the arm was adjusted to operate vertically. [0003] However, when the operator artificially adjusts the amount of operation between the boom and the arm to operate the tip of the arm in the vertical direction, the operator cannot visually recognize the arm. Since the operation mode controls the boom and the arm at the same time while checking the position of the tip of the arm, there is a face that it is difficult for even a skilled worker to operate the arm tip vertically with high accuracy and there is room for improvement. is there. In particular, if the arm tip cannot be operated vertically vertically during the lifting operation, the lifting object may come into contact with an adjacent wall surface or a projecting object on the ground, etc., causing damage to each other, and conversely, using a backhoe device If the working direction of the tip of the arm deviates from the vertical direction when driving a sheet pile or a pile into the ground, there is a problem that the working efficiency is reduced. An object of the present invention is to rationally construct a backhoe capable of vertically operating an arm tip at an arbitrary position. [0005] A feature of the present invention is that a boom, an arm, and a bucket are connected to a machine base in series, and a boom cylinder for driving the boom, an arm cylinder, and a bucket for driving the arm are provided. A boom sensor for measuring a swing angle of the boom with respect to the machine base, comprising a bucket cylinder to be driven, and a boom control valve for controlling a boom cylinder in a backhoe having an arm sensor for measuring the swing angle of the arm with respect to the boom; And each of the arm control valves for controlling the arm cylinder is a pilot pressure operation type in which the cylinder is extended by applying the pilot pressure to one of the pair of pressure acting portions, and contracted by applying the pilot pressure to the other. A pilot valve and an arm control valve that operate the boom control valve. The pilot valve provided in the ilot oil passage is operated separately, and a boom and an arm are provided with a man-made operating tool that can be operated individually.In addition, the man-made operating device is operated in the boom raising direction in the pilot oil passage of the boom control valve. A pressure sensor for detecting the raising operation that detects that the operation has been performed, and a pressure sensor for detecting the lowering operation that detects that the operation has been performed in the boom lowering direction are provided. The boom sensor to raise or lower the tip position of the arm along a linear vertical trajectory orthogonal to the machine base in accordance with a specific operation of the artificial operation tool,
Boom cylinder based on the measurement from the arm sensor,
A vertical control unit for controlling an arm cylinder, wherein the vertical control unit operates a pilot valve on a boom side by a manual operation tool, and when a pressure sensor for detecting a boom raising detects the boom raising operation, the arm control is performed. Valve on arm
The pilot pressure is also supplied to the oil passage on the arm control valve side where the pilot valve on the arm side is not operated by the manual operation tool so that the operation is switched to the ascending side. When it is detected that the boom lowering operation has been performed, the arm control valve is moved to the arm scraping side.
The pilot pressure is also supplied to the oil passage on the side of the arm control valve so as to perform the switching operation, and the operations of the boom control valve and the arm control valve are controlled so that the tip of the arm moves up and down along the vertical trajectory. Control means to provide
The operation is as follows. [0008] According to the first feature, the operator operates the artificial operation tool in a specific direction with the boom and the arm each set to an arbitrary initial posture. The vertical control means alone raises or lowers the arm tip position along the vertical trajectory based on the measurement values from the boom sensor and the arm sensor. [0010] [0011] [0012] The arm is intended to along the vertical trajectory operates automatically only by operating the manual control device of the boom in the rising direction when raising the arm tip position, reverse In the case of lowering, the arm is automatically operated just by operating the artificial operation tool in the descending direction and follows the vertical trajectory, so there is no need to provide special operation equipment and the operation form is reasonable and erroneous operation Is unlikely to occur. Embodiments of the present invention will be described below with reference to the drawings. As shown in FIG.
A machine base 3 is provided so as to be rotatable around an axis Y in a vertical posture with respect to a rubber crawler type traveling device 2 having
Equipped with a hydraulic turning motor M for turning the
A backhoe device B is provided at a front position of the machine base 3 by connecting the boom 4, the arm 5, and the bucket 6 in series.
A backhoe is provided with a driving unit E having an engine 7 and a driving unit F having a driving seat 8 on the machine base 3. The dozer device 1 is constructed so as to be driven up and down by a dozer cylinder C1. The backhoe device B is composed of a boom 4 having a base member 4E, an intermediate member 4F and a distal member 4G. A hydraulic type that swingably drives the boom 4 with respect to the machine base 3 is configured so that the distal end member 4G can be freely moved in a horizontal direction with respect to the base end member 4E by being swingably connected around the core. A boom cylinder C4, a hydraulic arm cylinder C5 for oscillating the arm 5 with respect to the boom 4, and a hydraulic bucket cylinder C6 for oscillating the bucket 6 with respect to the arm 5;
Is provided with a hydraulic offset cylinder CS that drives the distal end member 4G to move laterally with respect to the base end member 4E. A potentiometer-type boom sensor 4S for measuring the amount of swing of the boom 4 with respect to the machine base 3 and a potentiometer-type arm sensor 5S for measuring the amount of swing of the arm 5 with respect to the boom 4 are provided.
And a potentiometer-type offset sensor 4GS for measuring a lateral offset amount of the distal end member 4G with respect to the base end member 4E. As shown in FIG. 2, a pair of left and right travel control levers 10 and 10 are located at a position in front of the driver's seat 8 of the driver F.
And a pair of left and right operation levers 11L as artificial operation tools,
A panel 16 having an operation pedal 13 at a step 12 of the driving section F, and a dozer elevating lever 14 at the right side of the driver's seat 8 and an accelerator lever 15 for setting the number of revolutions of the engine 7. Have. The traveling operation levers 10 and 10 independently control the driving speeds of the left and right crawlers of the traveling device 2 to set the traveling speed and perform steering control, and the right one of the left and right operation levers 11L and 11R. Boom cylinder C4 with 11R forward operation
To the raising side, and the boom cylinder C4
Is controlled to the lower side, and the bucket cylinder C
6 is controlled to the scraping side, the bucket cylinder C6 is controlled to the discharging side by operating to the right, and the operating levers 11L, 11L are controlled.
The arm cylinder C5 is controlled to the discharge side by operating the left side 11L of R in the forward direction, the arm cylinder C5 is controlled to the scraping side by operating backward, and the turning motor M is controlled to the right by operating the right side. Control to the turning side and turn the motor M
Is controlled to the left turning side, the offset cylinder CS is controlled to the right offset side by depressing the operation pedal 13 to the right, and the offset cylinder CS is controlled to the left offset side by the depressing operation to the left. ing. As shown in FIG. 3, this backhoe is configured to perform vertical control for raising and lowering the arm tip position along a linear vertical trajectory K in a posture orthogonal to the turning surface J of the machine base 3. The panel 16 is provided with a mode selection switch 17 for performing this control, and a mode indicator lamp 18 which is turned on when this control is selected. As shown in FIG. 4, a hydraulic control system for the boom 4 and the arm 5 is formed (other hydraulic control systems are not described in detail). In this control system, a hydraulic oil pump P1 driven by the engine 7 and a pilot pump P2, a pair of boom pilot valves PV4 and PV4 for adjusting the oil pressure from the pilot pump P2 by operating the right operation lever 11 in the front-rear direction, and the left operation lever 11
A pair of arm pilot valves P for adjusting the oil pressure from the pilot pump P2 by operating in the front-rear direction
V5 and PV5, and a boom control valve V4 for supplying and discharging hydraulic oil from a hydraulic oil pump P1 to a boom cylinder C4, and an arm for supplying and discharging hydraulic oil from a hydraulic oil pump P1 to an arm cylinder 5 Oil passages UL4, DL for applying pilot pressure from pilot valves PV4, PV4, PV5, PV5 to control valve V5 for
4, UL5, and DL5 are formed. As shown in the figure, the pilot oil passages UL4, DL4, UL5, and DL5 for the boom and the arm are UL4, UL5 for the up control side and D for the down control side.
L4, DL5, and a pair of pilot oil passages UL4, DL4, UL5, and DL5, each of which is provided with a pressure regulating valve 19 # whose opening is electromagnetically adjusted. A switching valve 20 for setting the pilot oil passage UL4 and the pilot oil passage UL5 for raising the pilot for the arm to be in communication with each other; a pilot oil passage DL4 for the boom lowering control side and a pilot for the arm lowering control side; A switching valve 20 for setting the oil passage DL5 in communication with the oil passage DL5;
Further, pressure sensors 21 and 21 are provided in pilot oil passages for boom raising and lowering control. A control system is formed as shown in FIG. 5, and the control system includes a control device 22 having a microprocessor.
An input system for signals from the mode selection switch 17, the two pressure sensors 21 and 21, the boom sensor 4S, the arm sensor 5S, and the offset sensor 4GS is formed for (an example of the vertical control means). An output system is formed for each of the mode display lamp 18, the four pressure regulating valves 19 #, and the two switching valves 20, 20, and the control operation of the control device 22 is as follows.
Note that the pressure regulating valve 19 is configured as an electromagnetic operation type that obtains an opening proportional to the supplied current value, and the control device 22 changes the duty ratio of the intermittent signal to change the supply current value to the pressure regulating valve 19 in a PWM manner. The required pilot pressure is applied to the control valves V4 and V5 by setting the opening degree of the valve by the change, and the switching valves 20 and 20 are configured to be opened by supplying a control current. As shown in the flow chart of FIG. 6, when the vertical control is started, if the flag is set to the initial value "0", the state of the mode selection switch 17 is determined and the operation is ON. , Mode display lamp 18
, And the boom sensor 4S at that time,
The vertical trajectory K is set based on signals from the arm sensor 5S and the offset sensor 4GS (# 101 to # 103).
Steps). As shown in FIG. 3, this vertical trajectory K is a bucket pin 6 for connecting the bucket 6 at the arm tip position.
The trajectory K is set at a position passing the position of P, and is set by calculation based on signals from the three sensors 4S, 5S, and 4GS. Next, when the pressure sensor 21 detects an increase in pilot pressure, the switching valve 20 on the detected side is opened and the pressure from the pilot oil passage for the boom is applied to the pilot oil passage for the arm. By supplying the power, the arm 5 is operated in conjunction with the operation of the boom 4 and the control of the lifting / lowering routine is started. Further, when the mode selection switch 17 is turned off, and when this control is interrupted. When the detection is performed based on the signal from the pressure sensor 21, the flag is set to the initial value “0”, and the processing is continued until the processing is reset (# 104). To # 106, # 200, # 107 steps). The processing of the raising / lowering routine (# 200 step) is configured as shown in the flow chart of FIG. 7. In this processing, when the flag is the initial value "0", each pressure regulating valve 19 on the side to which the pressure acts is used. , 19 are set to the initial opening, the flag is set to “1”, and when the flag is “1”, each pressure regulating valve 1 on the side where pressure acts as described later.
A process is performed to set 9, 19 as the target opening (# 201 to # 201).
# 204 step). Next, the boom sensor 4S and the arm sensor 5
The bucket pin 6P moves up and down trajectory K based on the signal from S.
The target opening of each pressure regulating valve 19, 19 is set to an appropriate value based on a signal from the boom sensor 4S or the arm sensor 5S when it is on the locus K, On the other hand, if it deviates from the trajectory K, the target opening of the pressure regulating valves 19, 19 is set to a corrected value corresponding to the deviation (steps # 205 to # 207). This target opening is a value for separately setting the opening of each of the pressure regulating valves 19, 19, and the proper target opening is the boom sensor 4
Based on S or the rate of change of the signal from the arm sensor 5S, the opening becomes necessary immediately after the bucket pin 6P exists on the vertical trajectory. In addition, the corrected target opening is based on a signal from the boom sensor 4S or the arm sensor 5S when the operation amount of the boom 4 or the arm 5 is excessive or insufficient, and This is a value of the opening for obtaining the operation amounts of the boom cylinder C4 and the arm cylinder C5 required to return to the vertical trajectory K. Next, the amount of change in the signal of the boom sensor 4S per unit time (boom swing speed) and the amount of change in the signal of the arm sensor 5S per unit time (arm swing speed) are preset. To determine whether the proper relationship maintained
Only when the respective relationships are not maintained (only when the relative speeds are not in the proper relationship), the respective pressure regulating valves 19, 19
Is set to the corrected value (# 208, # 2)
09 steps). Specifically, the boom sensor 4S, and
The signal from the arm sensor 5S is integrated to determine whether each integrated value maintains a preset relative relationship for each unit time, and if not, the boom 4 and the arm 5 This is a process of suppressing the speed as one of the operating speeds is too high, and obtaining an opening of the pressure regulating valve 19 suitable for increasing the speed if the one operating speed is too low. Since the processing mode is set in this manner, for example, when lifting a heavy object during work, the bucket pin 6P
The vertical control is performed by mounting the lifting bracket at the position of, or by setting the position of the bucket pin 6P to the vertical upper position of the lifting target with the lifting wire provided and then turning on the mode selection switch 17. In this state, the arm 5 is also moved upward by interlocking with the start of operation of the boom 4 upward by simply operating the right operation lever 11 forward by locking the heavy object to the bracket or the wire. At the time of the upward movement, the control device 22 maintains the position control of the position of the bucket pin 6P through the vertical trajectory K and the operating speed of the boom 4 and the arm 5 in an appropriate relationship. Control, a heavy object can be lifted vertically upward while maintaining a smooth operation state at an accurate position.
In 1, the operation speed of the boom 4 on the ascending side can be adjusted to adjust the ascending speed of the heavy object. Similarly, for example, when performing a pile driving operation, the bucket pin 6P is set at an upper position of the pile, and the posture of the bucket 6 is set so that the bottom of the bucket 6 is located at the lower position. Mode switch 17
N operation enables vertical control. In this state, simply operating the right operation lever 11 backward causes the arm 5 to move in the same direction as the operation of the boom 4 on the lower side. In this downward movement, the control device 22 maintains the position control of the position of the bucket pin 6P through the vertical trajectory K and the operation speed of the boom 4 and the arm 5 in an appropriate relationship. Stakeout while maintaining a smooth operation state at an accurate position.
In FIG. 1, the operating speed of the boom 4 on the descending side can be adjusted to adjust the pile driving speed. [Other Embodiments] In addition to the above-described embodiment, the present invention selects and controls data stored in a memory or the like in advance based on signals from two sensors to set up and down trajectories. The control operation can be set so as to set a target (valve opening degree). Similarly, a boom sensor and an arm sensor can be used to determine that the bucket pin is located on the vertical trajectory. Can be compared with data stored in a memory or the like in advance based on the above signal. In addition, it is possible to determine whether the boom and the arm are operating at an appropriate speed relationship by comparing the data with data stored in a memory or the like in advance. Thus, a backhoe capable of easily operating the tip of the arm in an arbitrary position in the vertical direction according to the operation of the artificial operation tool is rationally constructed . In addition, when raising and lowering the arm tip position, a conventional operating tool can be operated in a natural direction to enable operation in a state in which erroneous operation hardly occurs .

[Brief description of the drawings] FIG. 1 is an overall side view of a backhoe. FIG. 2 is a plan view of an operation unit. FIG. 3 is a side view showing a vertical trajectory. FIG. 4 is a hydraulic circuit diagram FIG. 5 is a block circuit diagram of a control system. FIG. 6 is a flowchart of a main control operation. FIG. 7 is a flowchart of a lifting / lowering routine. [Explanation of symbols] 3 machines 4 Boom 4S boom sensor 5 arm 5S arm sensor 6 buckets 11 Artificial operation tools 22 Vertical control means C4 boom cylinder C5 arm cylinder C6 bucket cylinder K vertical trajectory

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) E02F 3/43 E02F 9/22-9/24

Claims (1)

(57) [Claims 1] A boom cylinder for driving a boom, an arm cylinder for driving an arm, and a bucket cylinder for driving a bucket by connecting a boom, an arm, and a bucket in series to a machine base. A boom sensor including: a boom sensor for measuring a swing angle of a boom with respect to a machine base; and a backhoe including an arm sensor for measuring a swing angle of an arm with respect to the boom, a boom control valve for controlling a boom cylinder, and an arm. Each of the arm control valves for controlling the cylinder is configured as a pilot pressure operation type such that the cylinder is extended by applying pilot pressure to one of the pair of pressure acting portions and contracted by application of pilot pressure to the other. The pilot valve provided in the pilot oil passage for operating the boom control valve and the pilot valve provided in the pilot oil passage for operating the arm control valve Each of the pilot valves is individually operated to provide a boom and an arm that can be individually operated, and a boom control valve is provided in a pilot oil passage to detect that the boom and the boom are operated in the boom raising direction. A pressure sensor for detecting the raising operation and a pressure sensor for detecting the lowering operation that detects operation in the boom lowering direction are provided. The boom cylinder and the arm cylinder are controlled based on the measured values from the boom sensor and the arm sensor so that the tip end position of the arm is moved up or down along a linear vertical trajectory perpendicular to the machine base in accordance with the operation. Vertical control means is provided. The vertical control means operates a pilot valve on the boom side by an artificial operating tool to control a pressure sensor for detecting boom raising. When Sa detects the boom-up operation, A the arm control valve
The pilot pressure is also supplied to the oil passage on the arm control valve side where the arm-side pilot valve is not operated by the manual operation tool so that the operation is switched to the boom raising side , and the pressure sensor for detecting the boom lowering is manually operated. When it is detected that the boom lowering operation by ingredients is performed, scraping arm the arm control valve
The pilot pressure is also supplied to the oil passage on the side of the arm control valve so as to perform the switching operation to the retracted side, and the operation of the boom control valve and the arm control valve is performed so that the tip of the arm moves up and down along the vertical trajectory. Backhoe provided with control means for controlling the