JPH1077659A - Movement controlling mechanism of deep digging excavator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the damage in an expansion arm having a plurality of stages expanded by combining them in a telescopic-shape. SOLUTION: A movement controlling mechanism of a deep digging excavator is equipped with an extension sensor 47 mounted to an expansion arm body 22 and detecting a state of expansion, a hydraulic motor 41 mounted to a swiveling base and rotating the swiveling base to the body, a driving oil supply mechanism 86 for conveying driving oil and an oil controlling mechanism 57 provided between the hydraulic motor 41 and driving oil supply mechanism and capable of controlling driving oil to be supplied. Then, it is constituted of an operation controlling mechanism provided between the extension sensor 47 and oil controlling mechanism 57, reducing flow of driving oil to the oil controlling mechanism 57 in the case the expansion arm body 22 is in a state of expansion to lower the revolution speed of the motor 41 and making the revolution speed of the swiveling base slow.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to, for example, civil engineering,
Regarding a deep excavator used for excavating a hole whose depth is extremely deep compared to its diameter in building construction, etc., it is particularly possible to prevent damage to a multi-stage telescopic arm body that expands and contracts in a telescopic shape. The present invention relates to a mechanism for restricting the operation of a deep excavator.

[0002]

2. Description of the Related Art Conventionally, in civil engineering work, construction work, and the like, it has often been necessary to excavate a hole whose depth is extremely deep as compared with its diameter. For example, holes for anchors for supporting steel towers, holes for embedding septic tanks, foundation works for buildings, well digging works and the like can be mentioned. In such a deep digging operation, an extremely deep hole having a depth of 15 to 20 meters has to be digged while the diameter of the hole is about 5 meters.

In such a deep excavation work, conventionally, a plurality of arms are assembled in a telescopic shape, and a deep excavator using a telescopic arm body which can expand and contract in its length direction (both arm excavators). Called) was actively used. This deep excavator has a structure in which the upper arm of the telescopic arm is connected to the boom of the excavator, and the lower end of the lower arm is connected to the clamshell bucket. The feature is that the clamshell bucket can be hung to the bottom of the deep hole by extending and contracting the arm body.

In such a deep excavator, the clamshell bucket can be hung to a deeper position than a general excavator (also called a backhoe) which excavates earth and sand by moving the bucket up and down. It was possible to excavate a deep hole in the vertical direction. However, in this deep digging excavator, the telescopic arm body for suspending the clamshell bucket has a structure in which a cylindrical arm is combined, and is extremely weak against impact and stress from the side direction. For this reason, when the extensible arm is swung back and forth or the excavator is swung in the hole dug down, the tip or side surface of the extensible arm comes into contact with the inner wall surface of the hole, and the extensible arm is deformed. Was a cause of failure. This telescopic arm has a structure in which the hollow arms are combined in the longitudinal direction so that they can slide with each other. Was unable to expand and contract. As described above, when digging a deep hole using a deep digging machine, when the telescopic arm body or boom is swung back and forth, or when the swivel is turned, the telescopic arm body and the wall surface of the deep hole come into contact with each other. The work could not be continued, and the operation required attention. For this reason, when the telescopic arm is inserted into the deep hole, it is preferable to perform only the operation of expanding and contracting the telescopic arm in the length direction of the excavated deep hole.

However, in the conventional deep excavator, the mechanism for swinging the telescopic arm and the boom and the mechanism for turning the swivel table are independent of each other, and the telescopic arm is extended and inserted into a deep hole. Even in the state, it was possible to swing the telescopic arm and the boom and to turn the swivel. For this reason, if the telescopic arm or the boom is swung or the swivel is rotated while the telescopic arm is inserted into the deep hole, the telescopic arm will be deformed by the driver's carelessness. , Which immediately caused a failure. Such an erroneous operation must be prevented beforehand. However, conventionally, the erroneous operation is controlled by the skill of the operator and the can, and the erroneous operation is affected by the experience of the operator.

[0006]

As described above, when the telescopic arm body collides with the inner wall surface of the dug deep hole and is deformed or bent, the arm of each step constituting the telescopic arm body slides. It will no longer work and will need repair. However, the arms of each step are formed in a straight line so as to be slidable, and it is difficult to repair the bending and deformation. For this reason, when operating a deep excavator using a telescopic arm, it is desirable to automatically regulate the operation in a specific state and prevent erroneous operation due to carelessness of the driver. . In view of this point, the invention of the present application automatically restricts the front and rear swing of the telescopic arm and the boom when the telescopic arm is inserted into the deep hole and the telescopic arm is extended. Further, at the same time, it is an object of the present invention to provide a motion control mechanism for a deep excavator capable of restricting the rotation of the swivel table and preventing the occurrence of failure of the telescopic arm body. Also, if one side of the clamshell bucket makes contact with the inner wall of the deep hole
An object of the present invention is to provide a motion control mechanism for a deep digging machine that can automatically restrict the swinging movement in the contact direction even if the swinging movement in the opposite direction is allowed.

[0007]

[MEANS FOR SOLVING THE PROBLEMS] For such a request,
The present invention provides a movable vehicle body, a swivel table mounted so as to be rotatable in the horizontal direction on the upper surface of the vehicle body, and a boom coupled to the upper surface of the swivel table so as to be swingable up and down, It is connected to the end of the boom so as to be able to swing up and down, and has a plurality of arms inside that can be expanded and contracted in length. In a deep digging machine consisting of a bucket connected to grab earth and sand, an extension sensor attached to the telescopic arm body to detect the expansion / contraction state, and a hydraulic motor attached to the swivel base to rotate the swivel base relative to the vehicle body And a drive oil supply mechanism for pumping the drive oil, an oil amount control mechanism interposed between the hydraulic motor and the drive oil supply mechanism to control the amount of drive oil supplied, an extension sensor and an oil amount control mechanism. Between When the telescopic arm body is in the extended state, the oil amount control mechanism comprises an operation regulating mechanism that reduces the flow rate of the drive oil to reduce the rotation speed of the hydraulic motor and reduces the rotation speed of the swivel base. The present invention provides a motion control mechanism for a deep excavator, characterized in that it is performed.

Further, the present invention provides a movable vehicle body, a swivel mounted on the upper surface of the vehicle body so as to be rotatable in a horizontal direction, and connected to the upper surface of the swivel so as to be vertically swingable. Boom, a telescopic arm that is connected to the end of the boom so that it can swing up and down, and that can store and extend multiple arms within it, and a lowermost stage of the telescopic arm In a deep excavator consisting of a bucket connected to the tip of an arm and grabbing earth and sand, an extension sensor attached to the telescopic arm body to detect the state of expansion and contraction, and attached to the telescopic arm body to detect the tilt angle Angle sensor, a hydraulic cylinder interposed between the swivel base and the boom to swing the boom up and down, and a hydraulic oil interposed between the boom and the telescopic arm to swing the telescopic arm up and down A cylinder, a hydraulic cylinder provided inside the telescopic arm body to expand and contract the telescopic arm body, a driving oil supply mechanism for pumping driving oil to each hydraulic cylinder, and a hydraulic oil supply mechanism interposed between each hydraulic cylinder and the driving oil supply mechanism. Input the detection signal from the extension sensor and the angle sensor to control the driving oil to be supplied and extend the telescopic arm, and the telescopic arm is tilted at a certain angle with respect to the vertical During the operation, the control signal is output to the oil amount control mechanism to restrict the telescopic arm body to swing only in the vertical direction, and further to restrict the telescopic arm body to be allowed only in the direction in which the telescopic arm body is reduced. The present invention provides a motion control mechanism for a deep excavator, comprising an operation control mechanism.

Further, the present invention relates to a movable vehicle body, a swivel mounted on the upper surface of the vehicle body so as to be rotatable in a horizontal direction, and connected to the upper surface of the swivel so as to be vertically swingable. Boom, a telescopic arm that is connected to the end of the boom so that it can swing up and down, and that can store and extend multiple arms within it, and a lowermost stage of the telescopic arm A deep excavator, which is connected to the tip of an arm and has a bucket for catching earth and sand, an elongation sensor attached to the telescopic arm for detecting the state of expansion and contraction, and excavation of the telescopic arm attached to the telescopic arm A lower bending moment sensor that detects the stress applied to the side of the machine, a hydraulic cylinder interposed between the swivel and the boom to swing the boom up and down, and a boom and telescopic arm A hydraulic cylinder interposed between the hydraulic cylinders to swing the telescopic arm up and down, a driving oil supply mechanism for pumping the driving oil to each hydraulic cylinder, and a driving oil interposed between each hydraulic cylinder and the driving oil supply mechanism Input the detection signals from the elongation sensor and the lower bending moment sensor to control the oil amount, and when the telescopic arm is extended and stress is applied to the lower side of the telescopic arm, the oil A motion control mechanism for a deep excavator, comprising: a control signal that outputs a control signal to a quantity control mechanism to restrict the telescopic arm body to swing only in a vertical direction. (The invention according to claim 3).

According to the present invention, a movable vehicle body, a revolving base mounted on the upper surface of the vehicle body so as to be rotatable in a horizontal direction, and a vertically movable swingably connected to the upper surface of the revolving base. Boom, a telescopic arm connected to the end of the boom so that it can swing up and down, and a plurality of arms can be housed inside the telescopic arm so that the length can be expanded and contracted. A deep excavator comprising a bucket connected to the tip of an arm and gripping earth and sand, an elongation sensor attached to the telescopic arm body for detecting the state of expansion and contraction, and an excavation of the telescopic arm body attached to the telescopic arm body An upper bending moment sensor that detects the stress applied to the side opposite to the machine, a hydraulic cylinder interposed between the swivel and the boom to swing the boom up and down, and a boom and telescopic arm. A hydraulic cylinder interposed between the hydraulic cylinders to swing the telescopic arm up and down, a driving oil supply mechanism for pumping the driving oil to each hydraulic cylinder, and a hydraulic oil supply mechanism interposed between each hydraulic cylinder and the driving oil supply mechanism. Input the detection signal from the oil amount control mechanism that controls the supplied drive oil and the elongation sensor and the upper bending moment sensor, and when the telescopic arm is extended and the stress is applied to the upper side of the telescopic arm, And a control mechanism for outputting a control signal to the oil quantity control mechanism to control the telescopic arm body to swing only in the vertical direction. It is provided (the invention according to claim 4).

Further, the present invention provides the above-mentioned telescopic arm body,
2. A base arm connected to a tip of a boom, a middle arm slidably inserted into the former arm, and a tip arm slidably inserted into the middle arm. The present invention provides a motion control mechanism for a deep excavator according to any one of claims 2, 3 and 5.

According to the present invention, the telescopic arm body includes a base arm connected to the tip of the boom, a middle arm slidably inserted into the base arm, and a slidably inserted into the middle arm. The extension sensor is fixed to the original arm, and the extension sensor outputs a detection signal when the middle arm or the extension arm is extended from the original arm, wherein the extension sensor outputs a detection signal. 2, 3, and 5
It is intended to provide a motion control mechanism for the deep digging machine according to the above (claim 6).

[0013]

Embodiments of the present invention will be described below with reference to the drawings. In the present embodiment, a deep excavator used for digging a hole deeper than its diameter in the direction perpendicular to the ground from the ground surface and deeper than its diameter is used. A description will be given by applying the form.

FIG. 1 is a perspective view showing the appearance of the entire deep excavator according to the present embodiment. The body 1 of this deep excavator
Crawlers 12 are wound around the left and right sides of the vehicle 1 in parallel with each other. By driving the crawler 12, the vehicle body 11 can be freely moved in the front-rear direction. A swivel 13 capable of turning 360 degrees in the horizontal direction is mounted on the upper part of the vehicle body 11. It is pivoted so that it can be done. This boom 14
A hydraulic cylinder 15 for raising and lowering the boom 14 is interposed between the center of the rotary table 13 and the front surface of the swivel 13.
A holder 23 is connected to the tip of the boom 14 by a pin 17 so as to be able to swing up and down. And hydraulic cylinder 1
The cylinder rod 8 and the holder 23 are connected by a pin 19.

The holder 23 has an elongated original arm 16.
Is fixed, and the holder 23 and the former arm 16 can swing vertically in an integrated manner. This former arm 16
Has, for example, an elongated shape in which a cross section of an inner hollow portion is formed by bending a thin steel plate. An elongated middle arm 20 is inserted through the lower end opening of the original arm 16 so as to be slidable in the length direction. The inner arm 20 has, for example, an elongated shape formed by bending a thin steel plate and having a hollow inner cross section having a rectangular shape. From the opening at the lower end of the middle arm 20, a slender tip arm 21
Are inserted so as to be slidable in the length direction.
The tip arm 21 is formed, for example, by bending a thin steel plate, and has an elongated shape with a hollow inner cross section being rectangular. The former arm 16, the middle arm 20, and the tip arm 21 constitute a telescopically assembled telescopic arm body 22 that can expand and contract in its length direction.
A hydraulic cylinder (not shown) for linearly extending and contracting the middle arm 20 and the front arm 21 from the lower end opening of the boom 14 is housed inside the telescopic arm body 22. Middle arm 2
0, The tip arm 21 can be expanded and contracted to an appropriate length.

A connecting unit 30 is fixed to the end of the above-mentioned tip arm 21, and the upper end of the connecting unit 31 is connected to the end of the connecting unit 30 by a pin 32. Therefore, the connection unit 31 is connected to the connection unit 3
It is suspended so that it can swing freely at the lower part of the zero. The lower end of the connection unit 31 is connected to the upper end of a suspension shaft 33, and a pair of shell buckets 36, 37 are connected to the left and right of the lower end of the linear suspension shaft 33. A hydraulic cylinder 34 as a hydraulic drive mechanism for operating the shell bucket 36 is interposed between the upper side surface of the suspension shaft 33 and the rear surface of the shell bucket 36. The upper side surface of the suspension shaft 33 and the shell bucket 37
A hydraulic cylinder 35 as a hydraulic drive mechanism for operating the shell bucket 37 is interposed between the rear surface and the rear surface. These suspension shaft 33, shell bucket 3
6, 37 and the hydraulic cylinders 34 and 35 maintain the pin 32 as its center of rotation so that it always faces vertically by its own weight. By extending and contracting the hydraulic cylinders 34, 35 simultaneously, the left and right shell buckets 36, 37
Can open and close its downwardly facing opening, and the shell buckets 36, 37 allow earth and sand to be dug from the bottom of the deep hole. The work of excavating earth and sand by the shell buckets 36 and 37 is the same as the function of a conventionally known clamshell bucket.

Next, FIG. 2 shows the use of this deep excavator.
The operation of digging a deep hole W will be specifically described. In the configuration of the deep excavator described with reference to FIG. 1, the vehicle body 11 can be moved above the side wall of the deep hole W by driving the crawler 12 and can be arranged at a work position. By extending and retracting the hydraulic cylinder 15, the boom 14 can be swung up and down.
The holder 23 and the former arm 16
Can be swung up and down. By operating these hydraulic cylinders 15 and 18 in cooperation, the elongated telescopic arm 22 can be inserted vertically into the deep hole W. In this insertion operation, the telescopic arm 22-b, the telescopic arm 22-a, and the telescopic arm 22 are performed in this order in FIG.

When the telescopic arm body 22 is inserted into the deep hole W in this manner, the middle arm 20 and the front arm 2
1 is extended in its length direction, and the lower end of the tip arm 21 is lowered to the bottom of the deep hole W. Then, the shell buckets 36 and 37 suspended from the lower end of the tip arm 21 come into contact with the bottom of the deep hole W. In this state, the hydraulic cylinders 34 and 35 are operated to respectively move the shell buckets 36 and 37 right and left. And then both shell buckets 3
By closing 6, 37, the earth and sand at the bottom of the deep hole W can be dug. Then, the shell buckets 36 and 37 that have seized the earth and sand are retracted by a hydraulic cylinder (not shown) housed inside the telescopic arm body 22 so that the middle arm 20 and the front arm 21 are housed inside the former arm 16. It can be lifted upward. Conversely, by operating the hydraulic cylinders 15 and 18 in cooperation with each other, the telescopic arm 22 is pulled out from the upper end opening of the deep hole W, and the shell buckets 36 and 37 are simultaneously drawn out of the deep hole W. Can be. The state where the shell buckets 36 and 37 are pulled out is indicated by shell buckets 36-b and 37-b in FIG. When the shell buckets 36-b and 37-b are lifted high as described above, the swivel base 13 is swiveled in the horizontal direction with respect to the vehicle body 11, and the shell buckets 36-b and 37-b are raised above the loading bed of the waiting truck. b, 37-b are moved. By operating the hydraulic cylinders 34 and 35, the left and right shell buckets 36-b and 37-b are opened, so that the excavated earth and sand can be discharged to a truck bed or the like. By such a procedure, a deep hole W can be sequentially dug down, and this operation is conventionally known.

As shown in FIG. 2, when the telescopic arm 22 is in the vertical position, the forearm 21 and the telescopic arm 22 are extended from the original arm 16, respectively, so that the shell buckets 36 and 37 are extended. Even when the load collides with the bottom of the deep hole W, the load acts only in the length direction of the telescopic arm body 22, so that the telescopic arm body 22 is not likely to be deformed. However, when the hydraulic cylinders 15 and 18 are erroneously operated and the boom 14 and the former arm 16 are swung up and down while the telescopic arm body 22 is extended, the shell buckets 36 and 37 are attached to the inner wall surface of the deep hole W. Will come in contact. This contact state is shown in FIG.
-A, 37-a. When the shell buckets 36-a and 37-a collide with the inner wall surface of the deep hole W, a load is applied to the tip of the extended telescopic arm body 22 from the lateral direction, and the extended middle arm 20-a and the front arm are extended. 21-a are respectively applied with stress, and the middle arm 2
0-a, the tip arm 21-a is deformed in a direction perpendicular to its length.

As described above, the middle arm 2 is
0. When the extensible arm 22 is extended by pulling out the tip arm 21, the strength is weak. By erroneously operating the hydraulic cylinders 15 and 18 as they are, the original arm 16-a, the middle arm 20-a, and the tip arm 21-a
As described above, when the entire telescopic arm 22-a is inclined obliquely with the deep hole W, an impact is applied to the side surface of the telescopic arm 22-a. When a stress is applied to the elongated telescopic arm 22-a from the lateral direction, the middle arm 20-a and the tip arm 21-a are naturally deformed and lose linearity. Even if the telescopic arm 22-a is reduced by the hydraulic cylinder, the middle arm 20-a and the leading arm 21-a cannot be retracted into the former arm 16-a. Further, if the turntable 13 is turned without operating the hydraulic cylinders 15 and 18, the side face of the deep hole W collides with the side face of the extending telescopic arm body 22, causing the same trouble. In the present invention, such a state is detected and the hydraulic cylinders 15, 1
8 and the operation of the swivel base 13 are automatically regulated.

Next, FIG. 3 is an explanatory diagram showing a positional relationship in which a main hydraulic drive mechanism and various sensors of the deep excavator in this embodiment are arranged.

Inside the turning table 13 described above, there is a vehicle body 11.
A hydraulic motor 41 for turning the swivel table 13 in the horizontal direction is stored. When the hydraulic motor 41 is driven, its rotational force is reduced by a gear (not shown) or the like, so that the swivel base 13 can be turned horizontally with respect to the vehicle body 11 fixed on the ground. And the swivel 13
The base of the hydraulic cylinder 15 is connected to the front side of
At the tip of this hydraulic cylinder 15 is a cylinder rod 4
2 is inserted so as to be able to expand and contract in its length direction, and the tip of the cylinder rod 42 is connected to the center of the boom 14. The hydraulic cylinder 1 is located at the center of the back of the boom 14.
8, a cylinder rod 43 is inserted at the tip of the hydraulic cylinder 18 so as to be extendable and contractible in the longitudinal direction thereof, and the tip of the cylinder rod 43 is connected to the rear upper portion of the holder 23. is there. Although not shown in FIG. 1 described above, a hydraulic cylinder 44 is housed inside the original arm 16 constituting the telescopic arm body 22 so as to be parallel to its length direction. Has a cylinder rod 45 inserted so as to be extendable and contractible in its length direction. The base of the hydraulic cylinder 44 is connected to the inner upper end of the former arm 16, and the lower end of the cylinder rod 45 is connected to the inner lower end of the tip arm 21. The structure in which the hydraulic cylinder 44 and the cylinder rod 45 are connected in the telescopic arm body 22 (for example, a double-speed winding with a wire and a pulley) is the same as a conventionally known structure. Detailed description is omitted.

At the upper end of the former arm 16, an angle sensor 46 which constantly detects the angle position of the former arm 16 with respect to the vertical direction and outputs an electric signal.
Is fixed. An extension sensor 47 that determines whether the middle arm 20 and the front arm 21 are extended from the original arm 16 and outputs the electric signal is fixed to the lower end of the original arm 16. This extension sensor 47
Has a structure like a proximity switch, for example. If the middle arm 20 extends beyond a predetermined length (for example, 30 cm) from the original arm 16, the telescopic arm 22 becomes It has a function of determining that it is in the extended state and outputting a signal. In addition, before and after the tip of the original arm 16, a lower bending moment sensor 48 which constantly detects how much bending moment is applied to the telescopic arm body 22 and outputs an electric signal, an upper bending moment The sensor 49 is fixed (in FIG. 3, the right side of the telescopic arm 22 is the lower side, and the left side is the upper side).

Next, FIG. 4 schematically shows a mechanism for controlling the function of the deep excavator by the hydraulic path system and the electric signal system in this embodiment.

In FIG. 4, the hydraulic system includes an operating unit 55, a driving unit 56, and a regulating unit 57. A hydraulic pilot signal system is provided between the operating unit 55, the driving unit 56, and the regulating unit 57. It is tied at 58. And the drive unit 5
6 and each hydraulic drive of the deep excavator (hydraulic cylinder 1
5, 18, and 44 and the hydraulic motor 41) are independently connected via a drive hydraulic system 59. That is, the hydraulic motor 41 and the hydraulic cylinders 15, 18 are directly connected to the drive unit 56, respectively, and the hydraulic cylinder 44 is connected to the drive unit 56 via the extension / restriction section 65. In addition, the above-described angle sensor 4
6. Elongation sensor 47, lower bending moment sensor 4
8. The upper bending moment sensor 49 is connected to the situation determination unit 66 by an electric signal cable for the detection signal system 60, respectively. Then, the situation determination unit 66
The control output of the control signal system 61 becomes a control signal system 61.
Reference numeral 1 denotes a connection between the restriction unit 57 and the expansion / contraction restriction unit 65.

Next, FIG. 5 shows the operation unit 55 described above.
Of FIG. 1 is described in detail. The operation unit 55 is installed in a cabin mounted on the swivel table 13, and is manually operated by an operator sitting in the cabin. The operation unit 55 outputs a pilot signal for control, and proportionally controls the main valve to control the hydraulic cylinders 15, 18, 44,
The hydraulic motors 41 can be operated simultaneously or independently. The operation unit 55 includes a boom operation unit 72 for swinging the boom 14 and a former arm 1.
An arm operating section 73 for swinging the telescopic arm 6 up and down, a telescopic operating section 74 for extending and retracting the telescopic arm body 22, and a turning operating section 75 for turning the swivel base 13 horizontally with respect to the vehicle body 11 are housed. Have been.

A hydraulic pump 86, which is a hydraulic source for generating a pilot signal, is driven by an engine 87 housed inside the swivel table 13. An oil tank filled with pressure oil is provided on the suction side of the hydraulic pump 86. Reference numeral 88 is connected, and a line of a pressure oil supply passage 89 is connected to the discharge side of the hydraulic pump 86. In parallel with the pressure oil supply passage 89, a drain passage 90 for collecting the returned pressure oil is provided.
The end of the drain path 90 is connected to the oil tank 8.
8 is connected. The pressure oil supply passage 89 and the drain passage 90 are also connected to another hydraulic device other than the operation unit 55, but the connection is omitted in FIG.

A pilot valve 77 and a pilot valve 7 for outputting a pilot signal are provided inside the boom operating section 72.
8, a pilot valve 79 and a pilot valve 80 for outputting a pilot signal are provided inside the arm operating section 73, and a pilot valve for outputting a pilot signal is provided inside the telescopic operating section 74. A pilot valve 81 and a pilot valve 82 for outputting a pilot signal are provided inside the turning operation unit 75. Only one of the pilot valve 77 and the pilot valve 78 can be selectively operated, and can be operated alternately. The pilot valve 79 and the pilot valve 80 can be selectively operated only one of them. It can be activated and can operate alternately. Further, only one of the pilot valve 81 and the pilot valve 82 can be selectively operated, and can be operated alternately.
Only one of the pilot valve 83 and the pilot valve 84 can be selectively operated, and can be operated alternately. A pressure oil supply passage 89 is connected to the normally closed sides of the pilot valves 77 and 79 inside the boom operating section 72, and a normally open side of the pilot valves 77 and 78 is connected to the drain passage 90. . Arm operation unit 7
The pressure oil supply passage 89 is connected to the normally closed side of the pilot valves 79 and 80 inside the pilot valve 3.
A drain path 90 is connected to the normally open side of the drains 9 and 80.
Inside the telescopic operation section 74, the pilot valve 8
A pressure oil supply passage 89 is connected to the normally closed side of the pilot valves 1 and 82, and a drain passage 9 is connected to the normally open side of the pilot valves 81 and 82.
0 is connected. A pressure oil supply passage 89 is connected to the normally closed sides of the pilot valves 83 and 84 inside the turning operation unit 75, and a drain passage 90 is connected to the normally opened sides of the pilot valves 83 and 84. is there.

A pilot signal can be output by the pilot valves 77 to 84. The pilot signal of the pilot valve 77 is E-1 and the pilot signal of the pilot valve 78 is E-2. The pilot signal of the valve 79 is F-1, the pilot signal of the pilot valve 80 is F-2, the pilot signal of the pilot valve 81 is G-1, and the pilot valve 8 is
2 is G-2 and the pilot valve 83
Is H-1 and the pilot signal of the pilot valve 84 is H-2. Among these pilot signals, E-1 sets the telescopic arm 22 to the boom 1
E-2 swings the telescopic arm 22 downward with respect to the boom 14. F-1 is for swinging the boom 14 downward with respect to the vehicle body 11, and F-2 is for swinging the boom 14 upward with respect to the vehicle body 11.
G-1 is for reducing the length of the telescopic arm 22, and G-2 is for extending the telescopic arm 22. Further, H-1 is for turning the swivel 13 to the right with respect to the vehicle body 11, and H-2 is used.
Is for turning the swivel base 13 to the left with respect to the vehicle body 11.

Next, FIG. 6 illustrates the internal structure of the drive unit 56 in detail. Inside the drive unit 56, there are four proportional control valves 95, 96, which can slide the spool by the pilot oil pressure signal and output drive oil proportional to the pressure of the pilot signal.
97 and 98 are arranged. These proportional control valves 95,
96, 97 and 98 each have three blocks,
It can be switched to three positions of "neutral", "tangent" and "reverse connection", and the flow rate of output pressure oil can be proportionally controlled by the position of the block switched to "tangent" or "reverse connection". it can. A hydraulic pump 86, which is a hydraulic source for supplying pressure oil to the drive unit 56, is disposed outside the operation unit 55 of the drive unit 56. The hydraulic pump 86 is an engine 87 housed inside the swivel 13. Is driven by This hydraulic pump 86
An oil tank 88 filled with pressure oil is connected to the suction side, and a line of a pressure oil supply path 99 is connected to the discharge side of the hydraulic pump 86. The pressure oil supply passage 99 is guided to the inside of the drive unit 56, and each proportional control valve 95, 96,
The ports 97, 98 are connected linearly to ports that are always in conduction in the "neutral" block, and the ends thereof are in communication with the oil tank 88.

The pressure oil supply path 99 is connected to the drive unit 5.
6, one of which is an adjustment path 100. The end of the adjustment path 100 is connected to a relief valve 101, and the other end of the relief valve 101 is connected to an oil tank 88.
Connected to An adjustment path 100 is connected to one normally closed port of the proportional control valve 95 via a check valve 103, and one normally closed port of the proportional control valve 96 is connected to the normally closed port via a check valve 104. Adjustment path 100 is connected,
One normally closed port of the proportional control valve 97 has a check valve 10
5 is connected to the regulating path 100 via the proportional control valve 9
The regulating path 100 is connected to one normally closed port 8 via a check valve 106. Also, the proportional control valves 95, 9
The drain path 102 is connected in common to the other normally closed ports of the ports 6 and 97.
Is connected to an oil tank 88.

The above-mentioned proportional control valve 95 is connected to the telescopic arm 22.
The hydraulic fluid is supplied to the hydraulic cylinder 44 in order to expand and contract the hydraulic cylinder 44. Oil ports A-1 and A-2 are connected to ports on the discharge side of the proportional control valve 95. The proportional control valve 96 supplies drive oil to the hydraulic cylinder 18 to swing the telescopic arm 22. Oil ports B-1 and B-2 are connected to ports on the discharge side of the proportional control valve 96. I have.
The proportional control valve 97 supplies drive oil to the hydraulic cylinder 15 to swing the boom 14, and the discharge-side ports of the proportional control valve 97 have oil passages C- 1 and C- 2.
Is connected. The proportional control valve 98 is connected to the swivel 13
The hydraulic fluid is supplied to the hydraulic motor 41 to rotate the hydraulic motor 41 left and right, and oil passages D-1 and D-2 are connected to ports on the discharge side of the proportional control valve 98.

Next, a pilot signal G-1 is connected to one pilot port of the proportional control valve 95, and a pilot signal G-2 is connected to the other pilot port. Then, the proportional control valve 9
5 is switched to a block of "tangent", the hydraulic cylinder 44 performs a reducing operation, and when the pilot signal G-2 is inputted, the proportional control valve 95 switches to a block of "reverse connection" and the hydraulic cylinder 44 is extended. Work. Further, a pilot signal K is connected to one pilot port of the proportional control valve 96, and a pilot signal L is connected to the other pilot port. Switch to block,
The hydraulic cylinder 18 is extended, and when the pilot signal L is input, the proportional control valve 96 is switched to the block of "reverse connection", and the hydraulic cylinder 18 performs a reducing operation. A pilot signal P is connected to one pilot port of the proportional control valve 97, and a pilot signal J is connected to the other pilot port. When the pilot signal P is input, the proportional control valve 97 has a “tangent”. When the pilot signal J is inputted, the proportional control valve 97 is switched to the block of "reverse connection", and the hydraulic cylinder 15 is extended.
Performs a reduction operation. Further, a pilot signal M is connected to one pilot port of the proportional control valve 98, and a pilot signal N is connected to the other pilot port. When the pilot signal M is input, the proportional control valve 98 becomes "tangent". When the pilot signal N is input, the proportional control valve 98 switches to the block of "reverse connection", and the hydraulic motor 41 switches the turntable 13 to the left. Direction.

Next, FIG. 7 explains in detail the circuit configuration inside the above-mentioned regulating unit 57. The regulating unit 57 has six electromagnetic switching valves 111 to 116 which are activated by electric signals. These electromagnetic switching valves 111 to 116 have the same structure, and each can switch between two blocks. In the blocks in the normal state of each of the electromagnetic switching valves 111 to 116, one port is always conductive and the other port is closed, and the ports of the blocks switched by an electric signal are connected in opposite directions. It has a structure. A drain path 110 that can be used in common is disposed inside the regulating unit 57, and the end of the drain path 110 communicates with the oil tank 88.

A drain path 110 is connected to one port of the electromagnetic switching valve 111 which is always conducting, and a pilot signal J is connected to the other port. The pilot signal F-1 is connected to the port which is connected. A drain path 110 is connected to one port of the electromagnetic switching valve 112 which is always conducting, and a pilot signal K is connected to the other port. Is connected to a pilot signal E-2. Further, a drain path 110 is connected to one port of the electromagnetic switching valve 113 which is always conducting, and a pilot signal L is connected to the other port, and the electromagnetic switching valve 113 is always closed. A pilot signal E-1 is connected to the port. Further, a drain path 110 is connected to one port of the electromagnetic switching valve 116 which is always conducting, and a pilot signal P is connected to the other port, and the electromagnetic switching valve 116 is always closed. A pilot signal F-2 is connected to the port.

Next, the drain passage 110 is connected to one port of the electromagnetic switching valve 114 which is always conductive, and the check valve 123 is connected to the other port which is always conductive.
Is connected to the pilot signal M via the. The pilot signal H is supplied to the normally closed port of the electromagnetic switching valve 114.
-1 is connected, a check valve 124 is interposed between the pilot signals H-1 and M, and a check valve 122 and a relief valve 1 are provided between the pilot signal M and the drain passage 110.
18 are connected in series. A throttle 120 having a narrow flow path is interposed between the connection point between the check valve 122 and the relief valve 118 and the pilot signal H-1.

The hydraulic circuit of the electromagnetic switching valve 115 has the same configuration as that of the electromagnetic switching valve 114. The aforementioned electromagnetic switching valve 1
The drain path 1 is connected to one of the 15 normally conducting ports.
The pilot signal N is connected via a check valve 126 to the other port which is connected to and is always on. A pilot signal H-2 is connected to a normally closed port of the electromagnetic switching valve 115, and the pilot signal H
-2 and N, there is a check valve 127 interposed between the pilot signal N and the drain path 110.
And a relief valve 119 are connected in series. A throttle 121 having a narrow flow path is interposed between the connection point between the check valve 125 and the relief valve 119 and the pilot signal H-2.

Each of these electromagnetic switching valves 111 to 116 is operated by an electric signal. A regulating signal Q is supplied to a solenoid SOL7 of the electromagnetic switching valve 111, a regulating signal R is supplied to a solenoid SOL6 of the electromagnetic switching valve 112, and
The control signal S is supplied to the solenoid SOL5 of the electromagnetic switching valve 113.
However, the restriction signal T is connected to the solenoid SOL4 of the electromagnetic switching valve 114, the restriction signal U is connected to the solenoid SOL3 of the electromagnetic switching valve 115, and the restriction signal V is connected to the solenoid SOL2 of the electromagnetic switching valve 116, respectively. is there.

Next, FIG. 8 shows the internal structure of the expansion / contraction regulating section 65 described above. An electromagnetic switching valve 130 and a relief valve 131 are connected in series inside the expansion / contraction regulating portion 65, an oil passage A-1 is connected to the electromagnetic switching valve 130, and an oil passage A is connected to the relief valve 131. -3 is connected.
The electromagnetic switching valve 130 is capable of alternately switching between two blocks of conduction and closing by a control signal X.
There is always a closed block. A check valve 132 is connected in parallel between both ends of the electromagnetic switching valve 130, and a check valve 133 is provided between both ends of the relief valve 131.
Are connected in parallel. The control signal X is connected to the solenoid SOL1 of the electromagnetic switching valve 130. In this circuit, the directions of the check valves 132 and 133 are set so that the drive oil flows from the oil passages A-1 to A-3, and the relief valve 131 is connected to the oil passage A-3. The characteristics are set so as to open at the pressure of.

FIG. 9 shows the internal structure of the situation determination unit 66 described above. This situation determination unit 6
Numeral 6 is for grasping the state of the telescopic arm body 22, comparing the value with a preset value according to the condition, and outputting a signal for regulating the operation of the deep excavator. The status determination unit 66 is configured by combining a nonvolatile storage element (for example, a ROM) and a central processing element (for example, a CPU), and includes a lower overload determination circuit 135 and an upper Overload discrimination circuit 1
36, expansion / contraction determination circuit 137, position / angle determination circuit 138,
A central control circuit 139 and a regulation signal generation circuit 140 are housed therein.

The output of the lower bending moment sensor 48 fixed to the telescopic arm 22 is input to the lower overload discriminating circuit 135,
The output of the upper bending moment sensor 49 fixed to 2 is input to an upper overload determining circuit 136. The output of the extension sensor 47 fixed to the telescopic arm 22 is input to an expansion / contraction determining circuit 137, and the output of the angle sensor 46 fixed to the telescopic arm 22 is input to a position / angle determining circuit 138. ing. The signals from the lower bending moment sensor 48, the upper bending moment sensor 49, the extension sensor 47, and the angle sensor 46 form a detection signal system 60.

The above-mentioned lower overload discriminating circuit 135 outputs a discrimination signal to the central control circuit 139 when the load becomes equal to or more than a preset load, based on a signal from the lower bending moment sensor 48. Similarly, the upper overload discrimination circuit 136 outputs a discrimination signal to the central control circuit 139 based on a signal from the upper bending moment sensor 49 when the load exceeds a preset load. Further, the expansion / contraction judging circuit 137 includes the extension sensor 47.
And outputs to the central control circuit 139 a signal indicating whether or not the telescopic arm 22 has expanded or contracted. The position / angle discriminating circuit 138 discriminates, based on a signal from the angle sensor 46, whether or not the angle is equal to or larger than a preset angle (for example, 20 degrees) and outputs the discrimination signal to the central control circuit 139. The central control circuit 139 contains a non-volatile memory, and can compare with a program in which a combination of various signals is stored and determine so that an optimal regulation signal can be output. . The central control circuit 139 outputs a judgment signal as a bus to the regulation signal generation circuit 140 based on the input signals. This regulation signal generation circuit 14
At 0, the control signals Q, R, S, T, U, V, and X can be output independently.

Next, the operation of this embodiment will be described. In the description of this operation, its operation will be described together with the truth table shown in FIG.

In this embodiment, the hydraulic cylinders 15, 18, and 44 and the hydraulic motor 4 in the deep excavator are used.
1 will be described, and the description of the operation for operating other mechanisms will be omitted. However, the operation of the other mechanisms is the same as the operation procedure of the conventionally known deep excavator, and does not change at all.

An outline of the operation will be described with reference to FIG. When each of the pilot valves of the operation unit 55 inside the cabin of the swivel base 13 is operated, a pilot signal for control is generated from the operation unit 55. These signals flow through the hydraulic pilot signal system 58 and are transmitted to the drive unit 56 and the regulating unit 57. The main valve of the drive unit 56 is operated by the hydraulic pilot signal flowing through the hydraulic pilot signal system 58, and the hydraulic cylinders 15, 18, 44 and the hydraulic motor 41 provided in the deep excavator can be freely controlled. In this case, depending on the situation of the deep excavator, the restricting unit 57 functions, and the operation is not restricted to the pilot signal output from the operation unit 55 as it is, but the operation may be restricted.

When the main valve of the drive unit 56 is switched, the pressure oil is transmitted from the drive hydraulic system 59, and the drive oil is supplied to the hydraulic cylinders 15, 18, 44 and the hydraulic motor 41, respectively. Then, the hydraulic motor 41 rotates to turn the swivel base 13 in the horizontal direction with respect to the vehicle body 11, and the swivel direction of the swivel base 13 follows the operation direction of the operation unit 55. When the drive oil is supplied to the hydraulic cylinder 15, the boom 14 moves to the turntable 13.
In the vertical direction to change the elevation angle. When the driving oil is supplied to the hydraulic cylinder 18, the original arm 16 (that is, the telescopic arm body 22) swings up and down at the tip of the boom 14, and the elevation angle thereof can be changed. Further, when the driving oil is supplied to the hydraulic cylinder 44, the hydraulic cylinder 44 expands and contracts, whereby the middle arm 20 and the front arm 21 are extended from the inside of the original arm 16, and the entire telescopic arm body 22 is extended or contracted. Will be.

<When the telescopic arm 22 is contracted>

When the telescopic arm 22 is contracted and the middle arm 20 and the front arm 21 are housed inside the former arm 16, the operation of the deep excavator is not restricted at all. That is, the middle arm 20 and the tip arm 21 are housed inside the former arm 16 and the telescopic arm body 2
When 2 is contracted, the telescopic arm 22 is in a state of high strength. For this reason, there is little possibility that each member constituting the telescopic arm body 22 is deformed even when a slight impact is applied. When the total length of the telescopic arm 22 is reduced to a minimum, the entire telescopic arm 22-b is pulled out from the deep hole W as shown in FIG. This is because it is not preferable to regulate each operation. The operation of each mechanism when the telescopic arm 22 is completely contracted will be described.

The extension sensor 47 shown in FIGS.
For example, it is a proximity switch or the like, and the extension sensor 47 is fixed to the outer surface of the former arm 16. A metal piece to be detected is fixed on the side surface of the tip of the middle arm 20 (the lower end in FIGS. 3 and 4), and the extension sensor 47 detects the presence or absence of this metal piece. Arm 20
It is possible to determine the state in which is extended from the former arm 16. When the middle arm 20 is housed inside the former arm 16, the extension sensor 47 is close to the metal piece,
The expansion sensor 47 detects the contracted signal by the expansion / contraction determination circuit 1
Tell 37. The expansion / contraction determination circuit 137 determines that the middle arm 20 is housed inside the original arm 16 and the expansion / contraction arm body 22 is completely reduced, and outputs a determination signal to the central control circuit 139. The central control circuit 139 compares the stored reference with the input signal, and outputs a control signal from the detection signal system 60 to the regulation signal generation circuit 140. Then, the regulation signal generation circuit 140 outputs the regulation signals Q, R, S, T, U, V, and X, respectively, and is transmitted to the solenoids SOL1 to SOL7, respectively.

That is, the regulation signal X is the solenoid SOL
1 to open the electromagnetic switching valve 130, and the restriction signal V is transmitted to the solenoid SOL2 to
The control signal U is transmitted to the solenoid SOL3 to switch the electromagnetic switching valve 115, and the control signal T
Is transmitted to the solenoid SOL4 to switch the electromagnetic switching valve 114, the regulation signal S is transmitted to the solenoid SOL5 to switch the electromagnetic switching valve 113, and the regulation signal R is transmitted to the solenoid SOL6 to switch the electromagnetic switching valve 112. , The restriction signal Q is transmitted to the solenoid SOL7 to switch the electromagnetic switching valve 111. In such a switched state, the hydraulic cylinders 15, 18, 44 and the hydraulic motor 41 are operated by operating the pilot valves 77 to 78 provided in the operation unit 55, and the deep excavator can be freely operated. Can work. No restrictions are imposed on this operation.

<< Operation for swinging the telescopic arm body 22 >>
>

In order to swing the telescopic arm 22 up and down with respect to the boom 14, the pilot valves 77 and 78 are operated. When the pilot valve 77 is opened (the pilot valve 78 is closed and not opened at the same time), the pressure oil from the hydraulic pump 86 passes through the pilot valve 77 from the pressure supply line 89 and becomes a pilot signal E-1 in FIG. Is output. The pilot signal E-1 passes through the electromagnetic switching valve 113 in FIG. 7 and is output as a pilot signal L. Then, the pilot signal E-1 is input to one port of the proportional control valve 96 in FIG. Switch to the block. Then, the pressure oil fed from the hydraulic pump 86 is supplied to the pressure oil supply path 99, the adjustment path 100, and the check valve 10.
4 and is output from the proportional control valve 96 to the oil passage B-2. The drive oil output to the oil passage B-2 is transmitted to the discharge chamber side of the hydraulic cylinder 18 in FIG. 3, so that the cylinder rod 43 is drawn into the hydraulic cylinder 18. For this reason, the holder 23 connected to the tip of the boom 14 by the pin 17 is rotated clockwise in FIG. Can be When the telescopic arm 22 is swung to an appropriate angle, the pilot valve 7
7, the output of the pilot signal E-1 is stopped, the proportional control valve 96 returns to the "neutral" block, the cylinder rod 43 is no longer retracted into the hydraulic cylinder 18, and the telescopic arm 22 is Stop at that position.

Next, when the pilot valve 78 is opened (the pilot valve 77 is closed and not opened at the same time),
The pressure oil from the hydraulic pump 86 passes through the pilot valve 78 from the pressure supply passage 89, and the pilot signal E-2 in FIG.
Is output as The pilot signal E-2 passes through the electromagnetic switching valve 112 in FIG. 7 and is output as a pilot signal K. Then, the pilot signal E-2 is input to the other port of the proportional control valve 96 in FIG. Switch to the block. Then, the pressure oil fed from the hydraulic pump 86 flows through the pressure oil supply passage 99, the adjustment passage 100, and the check valve 104, and is output from the proportional control valve 96 to the oil passage B-1. Since the drive oil output to the oil passage B-1 is transmitted to the pressure chamber side of the hydraulic cylinder 18 in FIG. 3, the cylinder rod 43 is pushed out from the hydraulic cylinder 18.
Therefore, the holder 23 connected to the tip of the boom 14 by the pin 17 is rotated counterclockwise in FIG.
3 (that is, the telescopic arm body 2).
2) is swung downward. When the telescopic arm 22 is swung to an appropriate angle, when the pilot valve 78 is closed and the output of the pilot signal E-2 is stopped, the proportional control valve 96 returns to the "neutral" block, and the cylinder rod 43 Is no longer pushed out of the hydraulic cylinder 18, and the telescopic arm 22 stops at that position.

<< Operation for Swinging Boom 14 >>

In order to swing the boom 14 up and down with respect to the swivel table 13, the pilot valves 79 and 80 are operated. When the pilot valve 79 is opened (the pilot valve 80 is closed and not opened at the same time), the pressure oil from the hydraulic pump 86 passes through the pilot valve 79 from the pressure supply passage 89 and becomes a pilot signal F-1 in FIG. Is output. The pilot signal F-1 passes through the electromagnetic switching valve 111 in FIG. 7 and is output as a pilot signal J. Then, the pilot signal F-1 is input to one port of the proportional control valve 97 in FIG. Switch to the block. Then, the pressure oil fed from the hydraulic pump 86 is supplied to the pressure oil supply path 99, the adjustment path 100, and the check valve 10.
5 and is output from the proportional control valve 97 to the oil passage C-2. Since the driving oil output to the oil passage C-2 is transmitted to the discharge chamber side of the hydraulic cylinder 15 in FIG. 3, the cylinder rod 42 is drawn into the hydraulic cylinder 18. Therefore, the boom 1 connected to the swivel 13
4 is rotated counterclockwise in FIG. 3, and the boom 14 is swung downward. When the boom 14 is swung to an appropriate angle, when the pilot valve 79 is closed and the output of the pilot signal F-1 is stopped, the proportional control valve 97 becomes "neutral".
, The cylinder rod 42 can no longer be driven into the hydraulic cylinder 15, and the boom 14 stops at that position.

Next, when the pilot valve 80 is opened (the pilot valve 79 is closed and not opened at the same time),
The pressure oil from the hydraulic pump 86 passes through the pilot valve 79 from the pressure supply path 89 and the pilot signal F-2 in FIG.
Is output as The pilot signal F-2 passes through the electromagnetic switching valve 116 in FIG. 7 and is output as a pilot signal P. Then, the pilot signal F-2 is input to the other port of the proportional control valve 97 in FIG. Switch to the block. Then, the pressure oil pressure-fed from the hydraulic pump 86 flows through the pressure oil supply path 99, the adjustment path 100, and the check valve 105, and is output from the proportional control valve 97 to the oil path C-1. The drive oil output to the oil passage C-1 is transmitted to the pressure chamber side of the hydraulic cylinder 15 in FIG. 3, so that the cylinder rod 42 is pushed out from the hydraulic cylinder 18.
For this reason, the boom 14 connected to the swivel 13 is rotated clockwise in FIG. 3, and the boom 14 is swung upward. When the boom 14 is swung to an appropriate angle, when the pilot valve 80 is closed and the output of the pilot signal F-2 is stopped, the proportional control valve 97 returns to the "neutral" block and the cylinder rod 42 The above is not pushed out from the hydraulic cylinder 15, and the boom 14 stops at that position.

<< Expansion / Retraction Operation of Telescopic Arm 22 >>

Next, when the telescopic arm 22 is operated to extend and contract, the pilot valves 81 and 82 are operated. As will be described later, the expansion and contraction operation of the telescopic arm body 22 is restricted by its angular position (for example, whether it is at least 20 degrees with respect to the vertical).
Depending on the situation, it may not operate even if the operation of decompression is performed. Further, in this state, the telescopic arm body 22 is reduced to the minimum, and an operation from this position should only be able to perform the operation of extending the telescopic arm body 22. However, for the purpose of explaining the outline of the operation, the description will be made under the setting that the telescopic arm body 22 can be expanded and contracted. It will be described later that the operation is restricted when the telescopic arm body 22 is extended and other conditions overlap.

First, the pilot valve 82 is operated to extend the telescopic arm body 22 and push out the middle arm 20 and the front arm 21 from the former arm 16.
When the pilot valve 82 is opened (the pilot valve 81 is closed and not opened at the same time), the pressure oil from the hydraulic pump 86 passes through the pilot valve 82 from the pressure supply passage 89 and becomes a pilot signal G-2 in FIG. Is output.
This pilot signal G-2 is input to one port of the proportional control valve 95 in FIG. 6, and switches the proportional control valve 95 to the block of "reverse connection". Then, the pressure oil fed from the hydraulic pump 86 flows through the pressure oil supply path 99, the adjustment path 100, and the check valve 103, and is output from the proportional control valve 95 to the oil path A-2. Since the drive oil output to the oil passage A-2 is transmitted to the pressure chamber side of the hydraulic cylinder 44 in FIG. 3, the cylinder rod 45 is pushed out from the inside of the hydraulic cylinder 44. For this reason, the middle arm 20 and the front arm 21 connected to the lower end of the cylinder rod 45 are pushed downward from the former arm 16 in FIG. 3, and the total length of the telescopic arm body 22 becomes longer. When the cylinder rod 45 slides inside the hydraulic cylinder 44, the driving oil on the discharge chamber side of the hydraulic cylinder 44 is discharged and output to the oil passage A-3. The drive oil discharged from the oil passage A-3 opens the relief valve 131 shown in FIG. 8 and passes as it is, passes through the electromagnetic switching valve 130 (opened), and flows into the oil passage A-1. . Then, the drive oil flowing through the oil passage A-1 passes through the proportional control valve 95 in FIG.
3 and is collected in the oil tank 88. (Note that, when the middle arm 20 and the tip arm 21 are pushed out of the former arm 16 in this way, the above-described extension sensor 47 detects the extension and shifts to the regulation system, but the operation of this regulation will not be described here. )

Next, the pilot valve 81 is operated to reduce the telescopic arm body 22 and retract the middle arm 20 and the front arm 21 into the inside of the former arm 16. When the pilot valve 81 is opened (pilot valve 8
2 is closed and not opened at the same time), hydraulic pump 8
6 from the pressure supply passage 89 through the pilot valve 81
And is output as a pilot signal G-1 in FIG. This pilot signal G-1 is input to the other port of the proportional control valve 95 in FIG. 6 to switch the proportional control valve 95 to a block of "tangent". Then, the hydraulic pump 86
From the pressure oil supply passage 99 and the adjustment passage 10
0, the fluid flows through the check valve 103, and the oil passage A
-1 is output. The drive oil output to the oil passage A-1 passes through the check valves 132 and 133 shown in FIG. 8 as it is and flows to the oil passage A-3. Then, since the driving oil is transmitted from the oil passage A-3 to the discharge chamber side of the hydraulic cylinder 44 in FIG. 3, the cylinder rod 45 is drawn into the hydraulic cylinder 44. Therefore, the middle arm 20 and the leading arm 21 connected to the lower end of the cylinder rod 45 are retracted into the former arm 16, and the total length of the telescopic arm body 22 becomes shorter. When the cylinder rod 45 slides inside the hydraulic cylinder 44, the driving oil on the pressure chamber side of the hydraulic cylinder 44 is discharged to the oil passage A-2. The drive oil discharged to the oil passage A-2 passes through the proportional control valve 95 in FIG. 6, flows through the drain passage 103, and is collected in the oil tank 88.

<< Operation for Turning the Turntable 13 >>

Next, when the swivel base 13 is rotated in the horizontal direction with respect to the vehicle body 11, it can be operated by operating the pilot valves 83 and 84. That is, when the pilot valve 83 is opened (the pilot valve 84 is closed and not opened at the same time), the pressure oil from the hydraulic pump 86 passes through the pilot valve 83 from the pressure supply passage 89 and the pilot signal H- in FIG. Output as 1. This pilot signal H-1 passes through the electromagnetic switching valve 114 and the check valve 123 in FIG.
Next, an input is made to one port of the proportional control valve 98 in FIG. 6, and the proportional control valve 98 is switched to a block of "tangent". Then, the pressure oil pressure-fed from the hydraulic pump 86 flows through the pressure oil supply path 99, the adjustment path 100, and the check valve 106, and is output from the proportional control valve 98 to the oil path D-1. The driving oil output to the oil passage D-1 is supplied to one port of the hydraulic motor 41 in FIG.
1 to drive the turntable 13 to turn rightward.

At this time, the pilot signal H-1
Passes through the opened electromagnetic switching valve 114 as it is, and passes through the check valve 123 in the forward direction, so that the flow rate of the pilot signal H-1 is unchanged since the flow rate of the output pilot signal M is not limited at all. It is output as pilot signal M. Therefore, the spool of the proportional control valve 98 switched to the “tangent” block by the pilot signal M is fully opened, and the pressure oil from the hydraulic pump 86 is output from the oil passage D-1 with the maximum amount of oil, and Motor 41
Rotates at normal speed.

Further, the pilot valve 84 is opened (the pilot valve 83 is closed and not opened at the same time). The signal is output as a signal H-2. This pilot signal H-2 passes through the electromagnetic switching valve 115 and the check valve 126 in FIG. 7 and is output as a pilot signal N, and then the proportional control valve 98 in FIG.
And the proportional control valve 98 is switched to the block of "reverse connection". Then, the pressure oil pressure-fed from the hydraulic pump 86 flows through the pressure oil supply path 99, the adjustment path 100, and the check valve 106, and is output from the proportional control valve 98 to the oil path D-2. The driving oil output to the oil passage D-2 is shown in FIG.
The inside is supplied to the other port of the hydraulic motor 41, and the hydraulic motor 41 is driven to turn the swivel table 13 leftward.

At this time, the pilot signal H-2
Passes through the opened electromagnetic switching valve 115 as it is, and passes through the check valve 126 in the forward direction, so that the flow rate of the pilot signal H-2 is unchanged since the flow rate of the outputted pilot signal N is not limited at all. Output as pilot signal N. Therefore, the proportional control valve 98 switched to the block of "reverse connection" by the pilot signal N is fully opened, the pressure oil from the hydraulic pump 86 is output from the oil passage D-2 with the maximum amount of oil, and the hydraulic motor 41 Rotates at normal speed.

As described above, under the condition that the telescopic arm body 22 is contracted, the hydraulic cylinders 15, 18 and 18 are operated by operating each of the pilot valves 77 to 84.
44, the hydraulic motor 41 can be operated. In these operations, it is possible to operate with the same operability as a normal deep excavator without any restrictions.

<When the telescopic arm 22 is extended>

When the pilot signal G-2 is output by operating the pilot valve 82 as described above, the hydraulic cylinder 4
The driving oil is supplied to the pressure chamber side of the cylinder rod 45 and the cylinder rod 45
Can be pushed out from the hydraulic cylinder 44. With the extension of the hydraulic cylinder 44, the middle arm 20 and the forearm 21 are pushed out from the former arm 16, and the total length of the telescopic arm body 22 becomes longer. Thus, the telescopic arm 2
When the total length of 2 is long, the telescopic arm 22 is in a state of being weak against an impact from the side. Therefore, the telescopic arm 2
If 2 is extended, the state is detected, and the situation determination unit 66 in FIG. 4 comprehensively determines from the signals from other sensors and regulates the operation of the deep excavator. By this regulation, damage or bending of the telescopic arm 22 which is vulnerable to impact is prevented. Situation determination unit 66
Since the operation restriction by the above-mentioned method differs depending on the situation where the deep excavator is placed, what kind of regulation is performed according to each setting situation will be described individually.

[Detection of Extension of the Telescopic Arm 22]

When the hydraulic cylinder 44 operates and the telescopic arm body 22 is extended, the middle arm 20 is pushed out from the original arm 16, and the extension sensor 47 detects that the middle arm 20 has been pulled out. That is, when the middle arm 20 is pulled out by about 30 cm from the former arm 16,
The proximity switch, which is the extension sensor 47, cannot recognize the metal piece fixed to the middle arm 20, so that the extension sensor 47 outputs a signal. This extension sensor 4
The signal of 7 is transmitted to the expansion / contraction determination circuit 137 in the situation determination unit 66 shown in FIG. Then, since the telescopic arm 22 has expanded, the central control circuit 139 determines that the other lower overload discriminating circuits 135 and the upper overload discriminating circuits 13
5. The determination signal determined by the combination with the determination signal from the position / angle determination circuit 138 is sent to the regulation signal generation circuit 140.
And start regulating the operation of the deep excavator.

[[When the telescopic arm 22 is at 20 degrees or less]]

The above-mentioned angle sensor 46 is used for the telescopic arm 2.
The angle of the telescopic arm 22 with respect to the vertical axis is always detected, and the deflection angle of the telescopic arm 22 with respect to the vertical axis is output to the position / angle discriminating circuit 138. The position / angle discriminating circuit 138 always calculates the detection signal from the angle sensor 46, and does not output the discriminating signal to the central control circuit 139 when the telescopic arm 22 is at 20 degrees or less with respect to the vertical axis. However, since the signal that the telescopic arm 22 is extended is input from the telescopic determination circuit 137 to the central control circuit 139, under this condition, the central control circuit 139 sends the control signal generation circuit 140 1
A determination signal for restricting the rotation of No. 3 is output. Then, the regulation signal generation circuit 140 continuously outputs the regulation signals Q, R, S, V, and X, but does not output the regulation signals T and U, and the solenoid SOL3 of the electromagnetic switching valves 114 and 115 in FIG. And stop supplying current to 4. For this reason, the electromagnetic switching valves 114 and 115 respectively return and are switched to the closed block.

Since the regulation signals Q, R, S, V, and X are continuously transmitted as described above, the electromagnetic switching valves 111, 1
12, 113, 116, and 130 are open, the "extendable arm 22 is extended" state, and the "extendable arm 22 is at an angle of 20 degrees or less" (this angle 20
The degree is an angle set in this embodiment, and is not limited to this angle. This angle is one example. In the state, the pilot signals from the pilot valves 77 to 80 are transmitted to the proportional control valves 96 and 97 as they are,
The swinging operation of the boom 14 and the telescopic arm 22 can be freely performed. This means that if the telescopic arm 22 is at an angle of 20 degrees or less with respect to the vertical axis, the telescopic arm 22 is inserted vertically into the deep hole W as shown in FIG. Telescopic arm 2 within the range of
This is because there is room left for swinging 2. When the telescopic arm body 22 extends, it becomes weak against impact,
If it is located vertically inside the deep hole W, the deep hole W
This is because there is little collision with the inner wall.

However, when the output of the restriction signals T and U is stopped and the electromagnetic switching valves 114 and 115 are closed, the operation of rotating the swivel 13 right and left is restricted. This is because if the telescopic arm body 22 is vertically inserted into the deep hole W, there is enough room to swing the boom 14 and the telescopic arm body 22, but when the swivel base 13 is rotated left and right, This is because the inner wall of the deep hole W collides with the side surface of the telescopic arm 22, which causes damage to the telescopic arm 22. For this reason, even if the pilot valves 83 and 84 are operated, the turntable 13 does not rotate at the normal rotation speed as described above, but turns left and right at a slow low-speed rotation. If the rotation is performed at such a low speed, it is known that there is a danger in the operation of rotating the worker GA compression arm body 22 in the cabin, and the operation is performed carefully. Further, even if the pilot valves 83 and 84 are erroneously operated, the swivel base 13 rotates at a low speed, so that the side surface of the telescopic arm 22 does not collide with the inner wall of the deep hole W. Hereinafter, a procedure in which the rotation of the swivel base 13 by the operation of the pilot valves 83 and 84 is restricted and the swivel base 13 is rotated at a low speed will be described.

When the pilot valve 83 shown in FIG. 5 is opened, the pressure oil discharged from the pump 86 is supplied to the pressure oil supply passage 8.
9. Pilot signal H-1 passing through pilot valve 83
Is output as This pilot signal H-1 is input to the regulating unit 57 as shown in FIG. 7, but the electromagnetic switching valve 114 is closed and the check valve 124 is in the opposite direction, so that it passes through the throttle 120 and the relief valve 118 Open and reduce pressure. The reduced pressure oil passes through the check valve 122 and flows out as a pilot signal M. In this way,
The pilot signal H-1 becomes a reduced pilot signal M. This pilot signal M is input to one port of the proportional control valve 98, and the spool of the proportional control valve 98 is moved in proportion to the pressure to "tangent". Will be switched to Then, as shown in FIG. 6, the pressure oil fed from the hydraulic pump 86 flows through the pressure oil supply passage 99, the adjustment passage 100, and the check valve 106, and is output from the proportional control valve 98 to the oil passage D-1. You.

The driving oil output to the oil passage D-1 is shown in FIG.
Inside, it is supplied to one port of a hydraulic motor 41, and the hydraulic motor 41 is driven to turn the swivel 13 to the right. However, the proportional control valve 98
Since the spool is moved by the pilot signal M having the reduced pressure, the oil amount of the driving oil output to the oil passage D-1 in this case decreases in proportion to the oil amount of the pilot signal M. . That is, in the normal case (the electromagnetic switching valve 11
4 is released), the amount of oil is smaller, the rotation speed of the hydraulic motor 41 to be rotated is low, and the turntable 13 is turned rightward at a slow speed. In this circuit, the throttle 120 acts to ensure the pressure of the other valves, and prevents the pressure from dropping sharply when the relief valve 118 is opened. If the pilot valve 83 is closed while the swivel table 13 is rotating, pressure is applied in the direction opposite to the pilot signal M due to inertia. This pressure passes through the check valve 124 and the pilot signal H-1. And flows out of the drain valve 90 through the pilot valve 83.

When the pilot valve 84 is opened, the pressure oil discharged from the pump 86 passes through the pressure oil supply passage 89 and the pilot valve 84 and is output as a pilot signal H-2. This pilot signal H-2 is input to the regulating unit 57 as shown in FIG. 7, but since the electromagnetic switching valve 115 is closed and the check valve 127 is in the opposite direction, the throttle 1
21 and the relief valve 119 is opened to open the drain passage 1
10, the pressure of the pilot signal H-2 is reduced. The reduced pressure oil passes through the check valve 125 and flows out as the pilot signal N. In this way, the pilot signal H-2 becomes the reduced pilot signal N. This pilot signal N is input to the other port of the proportional control valve 98, and the spool of the proportional control valve 98 is moved in proportion to the pressure. And switch to "reverse connection". Then, as shown in FIG. 6, the pressure oil fed from the hydraulic pump 86 flows through the pressure oil supply path 99, the adjustment path 100, and the check valve 106, and is output from the proportional control valve 98 to the oil path D-2. You.

The driving oil output to the oil passage D-2 is shown in FIG.
The inside is supplied to the other port of the hydraulic motor 41, and the hydraulic motor 41 is driven to turn the swivel 13 to the left. However, the proportional control valve 98
Since the spool is moved by the pilot signal N of the reduced pressure, the oil amount of the driving oil output to the oil passage D-2 in this case decreases in proportion to the oil amount of the pilot signal N. . That is, in the normal case (the electromagnetic switching valve 11
5 is released), the amount of oil becomes smaller, the rotation speed of the hydraulic motor 41 to be rotated becomes low, and the turntable 13 is turned leftward at a slow speed. In this circuit, the throttle 121 acts to guarantee the pressure of the other valves, and prevents the pressure from dropping abruptly when the relief valve 119 is opened. If the pilot valve 84 is closed while the swivel table 13 is rotating, pressure is applied in the direction opposite to the pilot signal N due to inertia. , And is discharged from the drain valve 90 through the pilot valve 84.

[[When the telescopic arm 22 is at least 20 degrees]]

Next, by operating the hydraulic cylinders 15 and 18, the boom 14 and the telescopic arm 22 are swung, and the telescopic arm 22 may be inclined at an angle of 20 degrees or more with respect to the vertical axis. . As described above, when the inclination angle of the telescopic arm 22 is increased, the central control circuit 139 regulates the operation. That is, as shown in FIG. 2, when the telescopic arm 22 is greatly inclined inside the deep hole W, the distal end of the telescopic arm 22 easily collides with the inner wall of the deep hole W. Thus, the telescopic arm body 22
If the angle is larger than the vertical axis, only the operation of returning the telescopic arm body 22 in the vertical direction and the operation of reducing it in order to prevent damage due to a collision are permitted, and all other operations are restricted. .

As shown in FIG. 9, the aforementioned angle sensor 4
The angle of the telescopic arm 22 detected at 6 is always input to the position / angle determining circuit 138 as a detection signal. When the position and angle determination circuit 138 determines from the detection signal that the telescopic arm 22 is inclined at an angle of 20 degrees or more with respect to the vertical axis, the position and angle determination circuit 138 outputs the determination signal to the central control circuit 13.
9 is output. Under this condition, the central control circuit 13
9 permits the regulation signal generation circuit 140 to only swing the telescopic arm 22 downward (in FIG. 2, to swing the telescopic arm 22 counterclockwise) and to reduce the telescopic arm 22 only, A determination signal for restricting other operations is output. Then, the regulation signal generation circuit 140 outputs the regulation signal R
Continuously output as it is, but the regulation signals Q, S, V,
T, U, and X are not output, and the electromagnetic switching valve 112 in FIG.
Current is supplied only to the solenoid SOL6 of the other solenoid valves SOL1 to SOL1 of the other solenoid-operated directional control valves 111, 113 to 130.
Stop the current to 5,7.

As described above, in the state where the telescopic arm 22 is extended, and the angle of the telescopic arm 22 is equal to or more than 20 degrees (the angle of 20 degrees is set in this embodiment). In this state, only the pilot signal E-2 from the pilot valve 78 can be directly transmitted to the proportional control valve 96. . When the pilot valve 78 is opened, a pilot signal E-2 is output and transmitted to the pilot signal K through the electromagnetic switching valve 112 in the regulating unit 57. This pilot signal K is applied to the other port of the proportional control valve 96, and the proportional control valve 96 is switched to the “tangent” block to drive the driving oil from the hydraulic pump 86 to the pressure chamber side of the hydraulic cylinder 18 in FIG. Supply. For this reason, the cylinder rod 43 is pushed out from the hydraulic cylinder 18 and the telescopic arm body 22 is pushed out.
Is rotated counterclockwise in FIG. 3 to swing vertically. In such swinging of the telescopic arm 22, a deep hole W
The angle of the telescopic arm 22 is corrected so that the telescopic arm 22 is parallel to the deep hole W in the inside, and it is possible to prevent the inner wall of the deep hole W from colliding with the telescopic arm 22. If the telescopic arm 22 is converged at an angle of 20 degrees or less with respect to the vertical axis, the telescopic arm 22 is inserted vertically into the deep hole W as shown in FIG.
This is because the telescopic arm body 22 can be positioned in the range of the space of the inner diameter of the arm.

Under these setting conditions, the electromagnetic switching valve 11
4 and 115 are closed, and when the above-mentioned pilot signals H-1 and H-2 are input, the turntable 13 is rotated at a low speed due to the decrease in the flow rates of the pilot signals M and N as described above, and the rapid rotation is performed. Is restricted, it is possible to prevent the telescopic arm 22 from colliding with the inner wall of the deep hole W.

Further, since the regulation signals Q, S, V, X are not supplied to the electromagnetic switching valves 111, 113, 116, respectively, the electromagnetic switching valves 111, 112, 116 are closed. Therefore, pilot signals E-1, F-1, and F-2 are not output as pilot signals J, L, and P, respectively, and the operation of proportional control valves 96 and 97 is restricted. Therefore, even if an operator operates the pilot valves 77, 79, 80, no drive oil is supplied to the pressure chamber side and the discharge chamber side of the hydraulic cylinder 15 and the discharge chamber side of the hydraulic cylinder 18, and the boom by the hydraulic cylinder 15 14 is restricted, and at the same time, the telescopic arm body 22 is moved by the hydraulic cylinder 18 as shown in FIG.
Is regulated in the clockwise direction. In this manner, if the telescopic arm body 22 is tilted by more than the set angle of 20 degrees, the operation of the hydraulic cylinders 15 and 18 is restricted, and the hydraulic cylinder 18 causes the telescopic arm body 22 to swing vertically. Only is allowed. By this regulation, the telescopic arm body 22 that is telescopic and tilted at an angle greater than the danger angle is prevented from swinging only in the vertical direction and colliding with the inner wall of the deep hole W.

Next, since the restriction signal X is not output from the restriction signal generation circuit 140 to the solenoid SOL1, the electromagnetic switching valve 130 is closed. When the pilot valve 81 is opened and the pilot signal G-1 is output in this state, the pilot signal G-1 switches the proportional control valve 95 to the "tangent" side, and the driving oil is output to the oil passage A-1. Can be The drive oil output from the oil passage A-1 flows through the check valves 132 and 133 as it is in FIG. The driving oil is supplied to the oil passage A in FIG.
Since the pressure is transmitted to the discharge chamber side of the hydraulic cylinder 44 from -3, the cylinder rod 45 is retracted into the hydraulic cylinder 44. Therefore, the middle arm 20 and the leading arm 21 connected to the lower end of the cylinder rod 45 are retracted into the former arm 16, and the total length of the telescopic arm body 22 becomes shorter. When the cylinder rod 45 slides inside the hydraulic cylinder 44, the driving oil on the pressure chamber side of the hydraulic cylinder 44 is discharged to the oil passage A-2. The drive oil discharged to the oil passage A-2 passes through the proportional control valve 95 in FIG. 6, flows through the drain passage 103, and is collected in the oil tank 88. In this way, the cylinder rod 45 is housed in the hydraulic cylinder 44, and the operation of contracting the telescopic arm 22 is not restricted at all, and the telescopic arm 22 can be contracted as in the normal operation. This is an operation in the direction of contracting the telescopic arm body 22. Since the possibility that the telescopic arm body 22 collides with the inner wall of the deep hole W is reduced, there is no operation for reducing the telescopic arm body 22 in order to improve safety. This is because it is preferable not to regulate.

When the pilot valve 82 is opened, a pilot signal G-2 is output. The pilot signal G-2 switches the proportional control valve 95 to the "reverse connection" side, and the driving oil is supplied to the oil passage A-2. Is output. The drive oil that has flowed out into the oil passage A-2 enters the pressure chamber side of the hydraulic cylinder 44 in FIG. 3 and acts in a direction to push out the cylinder rod 45 from the hydraulic cylinder 44. When this cylinder rod 45 is pushed out from the hydraulic cylinder 44, the driving oil remaining on the discharge chamber side of the hydraulic cylinder 44 is discharged from the oil passage A-3, and the relief valve 1
31 to open and attempt to flow in the direction of the electromagnetic switching valve 130, but since the electromagnetic switching valve 130 is closed, the oil passage A
It does not flow in the direction of -3. Also, check valves 132 and 13
3 are reversed, these check valves 132,
Also, the driving oil cannot flow from the oil passage A-3 to the oil passage A-1. For this reason,
Even when the pilot valve 82 is opened, the cylinder rod 45 is not pushed out of the hydraulic cylinder 44, and
2 cannot be extended. Thus, the electromagnetic switching valve 1
When the pilot valve 82 is operated, the extension of the cylinder rod 45 is restricted by closing the 30, and as a result, the telescopic arm 22 cannot be extended further, and the telescopic arm 22 collides with the inner wall of the deep hole W. Can be prevented.

[[When a load is applied to the lower side of the telescopic arm 22]]

Next, as shown in FIG. 2, with the telescopic arm 22 inserted into the deep hole W, the hydraulic cylinder 15 or 18 is operated to swing the telescopic arm 22 to dig the deep hole W deep. A description will be given of the regulation in the case of colliding or pressing against the wall on the excavator side (the inner wall on the right side in FIG. 2). The load applied to the lower surface of the telescopic arm 22 (the right side of the telescopic arm 22 in FIG. 2 is downward) is constantly detected by the lower bending moment sensor 48 (for example, a detecting device such as a strain gauge). The detection signal is input to the lower overload determination circuit 135. For this reason, when the telescopic arm 22 collides with or is pressed against the inner wall of the deep hole W, the load applied to the telescopic arm 22 is detected by the lower bending moment sensor 48, and the lower overload discriminating circuit is used as a detection signal. Enter 135.
When the input detection signal is larger than a preset reference load, the lower overload determination circuit 135 determines that a large load has been applied to the lower side of the telescopic arm 22 and determines the determination signal. To the central control circuit 139. In this state where the telescopic arm 22 is extended,
And "a load was applied to the lower side of the telescopic arm 22"
In this state, the central control circuit 139 regulates the telescopic arm body 22 so as not to swing further toward the inner wall of the deep hole W.

That is, since the central control circuit 139 outputs a discrimination signal for regulation to the regulation signal generation circuit 140, the regulation signal generation circuit 140 outputs regulation signals S, V, X, and the regulation signals Q, R, The output of T and U is stopped. Therefore, each of the electromagnetic switching valves 111, 112, 114 and 115 is closed, and each of the electromagnetic switching valves 113, 116 and 130 is opened. Then, even if the pilot valves 78 and 79 are operated to output the pilot signals E-2 and F-1, the proportional control valves 96 and 97 are not actuated by the pilot signals E-2 and F-1, and Pressure oil is not supplied to the oil passage C-2 of the hydraulic cylinder 15 and the oil passage B-1 of the hydraulic cylinder 18. Due to this restriction, the boom 14 is prevented from rotating counterclockwise in FIG. 3 by the hydraulic cylinder 15, and the telescopic arm 22 is prevented from rotating counterclockwise in FIG. 3 by the hydraulic cylinder 18. In this manner, the telescopic arm 22 cannot be swung toward the inner wall (the right side in FIG. 2) on the near side of the deep excavator of the deep hole W under the control of the central control circuit 139, and no more. Cannot be applied to the telescopic arm 22, and it is possible to prevent the occurrence of stress such that the telescopic arm 22 is bent.

However, since the electromagnetic switching valve 113 is open, the pilot signal E-1 generated by opening the pilot valve 77 passes through the electromagnetic switching valve 113 to become the pilot signal L, and the proportional control valve 96 The drive oil is supplied to the oil passage B-2 by switching to "reverse connection".
For this reason, the drive oil is input to the discharge chamber side of the hydraulic cylinder 18, acts to draw the cylinder rod 43 into the hydraulic cylinder 18, and causes the telescopic arm 22 connected to the cylinder rod 43 to move clockwise in FIG. Can be swung in any direction. Further, since the electromagnetic switching valve 116 is open, the pilot signal F-2 generated by opening the pilot valve 80 passes through the electromagnetic switching valve 116 to become the pilot signal P, and the proportional control valve 97 is set to “tangent”. To supply the driving oil to the oil passage C-1. For this reason, the driving oil is input to the pressure chamber side of the hydraulic cylinder 15 and acts to push the cylinder rod 42 out of the hydraulic cylinder 15 to swing the boom 14 connected to the cylinder rod 42 clockwise in FIG. be able to. As described above, the operation of the deep excavator by the pilot valves 77 and 80 allows the telescopic arm body 22 only in a direction away from the inner wall (the right side in FIG. 2) in front of the deep hole W. The arm body 22 can be swung in a direction opposite to the side surface on which the load is applied. By this operation, it is possible to swing in the direction of eliminating the load applied to the telescopic arm 22 and prevent the telescopic arm 22 from being deformed or bent.

In this case, the electromagnetic switching valve 11
4 and 115 are closed, and when the above-mentioned pilot signals H-1 and H-2 are input, the turntable 13 is rotated at a low speed due to the decrease in the flow rates of the pilot signals M and N as described above, and the rapid rotation is performed. Is restricted, it is possible to prevent the telescopic arm 22 from colliding with the inner wall of the deep hole W.

[[When a load is applied to the upper side of the telescopic arm 22]]

Also, as shown in FIG. 2, with the telescopic arm 22 inserted into the deep hole W, the hydraulic cylinder 15 or 18 is operated to swing the telescopic arm 22 to excavate the deep hole W deep. The wall opposite to the machine (the inner wall on the left side in FIG. 2)
A description will be given of the regulation of the operation in the case of colliding with or pressing against the vehicle. The load applied to the upper surface of the telescopic arm 22 (the left side of the telescopic arm 22 in FIG. 2 is the upper side) is always detected by the upper bending moment sensor 49 (for example, a detecting device such as a strain gauge). The detection signal is input to the upper overload discrimination circuit 136. Therefore, when the telescopic arm body 22 collides with or is pressed against the inner wall of the deep hole W, the load applied to the telescopic arm body 22 is detected by the upper bending moment sensor 49, and the upper overload determination circuit 136 is used as a detection signal.
To enter. In the upper overload determination circuit 136,
If the input detection signal is larger than a preset reference load, it is determined that a large load is applied to the upper side of the telescopic arm 22 and the determination signal is sent to the central control circuit 1.
Output to 39. In the state where the telescopic arm 22 is extended and the state where a load is applied to the upper side of the telescopic arm 22, the central control circuit 139 determines that the telescopic arm 22 has a deeper hole W Is regulated so as not to swing in the direction of the inner wall.

That is, since the central control circuit 139 outputs a discrimination signal for regulation to the regulation signal generation circuit 140, the regulation signal generation circuit 140 outputs regulation signals Q, R, X, and the regulation signals S, T, The output of U and V is stopped. Therefore, each of the electromagnetic switching valves 113, 114, 115, and 116 is closed, and each of the electromagnetic switching valves 111, 112, and 130 is opened. Then, even if the pilot valves 77 and 80 are operated to output the pilot signals E-1 and F-2, the proportional control valves 96 and 97 are not operated by the pilot signals E-1 and F-2, No drive oil is supplied to the oil passage C-1 of the hydraulic cylinder 15 and the oil passage B-2 of the hydraulic cylinder 18. Due to this restriction, the boom 14 is not rotated clockwise in FIG. 3 by the hydraulic cylinder 15, and the telescopic arm 22 is not rotated clockwise in FIG. 3 by the hydraulic cylinder 18. Thus, the telescopic arm body 22 is restricted by the central control circuit 139 so that the deep hole W
The inner wall on the opposite side of the deep excavator (right side in Fig. 2)
Can not be swung toward, and no more load can be applied to the telescopic arm body 22,
It is possible to prevent the occurrence of stress such that the telescopic arm 22 is bent.

However, since the electromagnetic switching valve 112 is open, the pilot signal E-2 generated by opening the pilot valve 78 passes through the electromagnetic switching valve 112 to become the pilot signal K, and the proportional control valve 96 is opened. The drive oil is supplied to the oil passage B-1 by switching to "tangent".
For this reason, the driving oil is input to the pressure chamber side of the hydraulic cylinder 18 and acts to push the cylinder rod 43 out of the hydraulic cylinder 18, and the telescopic arm 22 connected to the cylinder rod 43 is moved in the counterclockwise direction in FIG. Can be rocked. Further, since the electromagnetic switching valve 111 is open, the pilot signal F-1 generated by opening the pilot valve 79 passes through the electromagnetic switching valve 111 to become a pilot signal J, and the proportional control valve 97 is set to “reverse connection”.
And the drive oil is supplied to the oil passage C-2. Therefore, the driving oil is input to the discharge chamber side of the hydraulic cylinder 15,
Acting so as to pull the cylinder rod 42 into the hydraulic cylinder 15, the boom 14 connected to the cylinder rod 42 can be swung counterclockwise in FIG. As described above, the operation of the deep excavator by the pilot valves 78 and 79 allows the telescopic arm body 22 only in a direction from the inner wall (the left side in FIG. 2) on the opposite side of the deep hole W to the near side. The telescopic arm 22 can be swung in the direction opposite to the side face on which the load is applied. By this operation, it is possible to swing in the direction of eliminating the load applied to the telescopic arm 22 and prevent the telescopic arm 22 from being deformed or bent.

In this case, the electromagnetic switching valve 11
4 and 115 are closed, and when the above-mentioned pilot signals H-1 and H-2 are input, the turntable 13 is rotated at a low speed due to the decrease in the flow rates of the pilot signals M and N as described above, and the rapid rotation is performed. Is restricted, it is possible to prevent the telescopic arm 22 from colliding with the inner wall of the deep hole W.

[0097]

As described above, in the motion restricting mechanism for a deep excavator according to the present invention, when the extension sensor detects that the telescopic arm is extended, the telescopic arm is easily deformed by stress. And the oil amount control mechanism acts to limit the amount of drive oil supplied to the hydraulic motor. For this reason, the rotation speed of the hydraulic motor decreases,
The rotation speed of the turntable with respect to the vehicle body decreases. This is a state in which the telescopic arm body is extended while being inserted into the hole being excavated. In this state, the rotation of the swivel base together with the telescopic arm body is slowed, and the excavation is performed on the side of the telescopic arm body. Rotate slowly so that the inner wall of the hole did not collide,
It is possible to call attention to the operator. In addition, even if the swivel table is inadvertently rotated in this state, it takes time until the inner wall of the excavated hole collides with the side surface of the telescopic arm body, and it is possible to prevent collision due to erroneous operation. 1)).

In the motion control mechanism for a deep excavator according to the present invention, the extension sensor detects extension of the telescopic arm, and the telescopic arm is at a predetermined angle or more by the angle sensor. When this is detected, the operation restricting mechanism starts operating in response to these signals, and restricts the operation of the hydraulic cylinder that swings the boom and the hydraulic cylinder that swings the telescopic arm. In this regulation, each hydraulic cylinder does not swing the boom and the telescopic arm at an angle equal to or greater than a predetermined angle, and restricts the operation only in a direction in which the telescopic arm approaches vertical. That is, each hydraulic cylinder is operated only in a direction converging within a predetermined angle range, and does not swing in a direction larger than the predetermined angle. For this reason, even if an attempt is made to incline the telescopic arm body in the dug hole, it cannot be inclined beyond the set angle, and the arm is always kept within an angle within a safe range. Further, since the operation of extending the telescopic arm is stopped and only the operation of contracting is allowed, the collision of the telescopic arm inside the dug hole can be prevented (the invention according to claim 2).

In the motion control mechanism of the deep excavator according to the present invention, the extension sensor detects that the telescopic arm is extended, and the lower bending moment sensor applies a stress to the side surface of the telescopic arm. Is detected, the operation restricting mechanism starts operating based on these signals, and restricts the operation of the hydraulic cylinder for rocking the boom and the hydraulic cylinder for rocking the telescopic arm. In this regulation, each hydraulic cylinder allows the boom and the telescopic arm to swing only in the direction opposite to the excavator, and restricts the operation of swinging toward the near side of the excavator. When the stress is detected by the lower bending moment sensor, the telescopic arm is in contact with the inner wall on the near side of the excavator inside the dug hole. The telescopic arm body can be prevented from being deformed by swinging (the invention according to claim 3).

In the motion control mechanism for a deep excavator according to the present invention, the extension sensor detects extension of the telescopic arm, and the upper bending moment sensor applies a stress to the side surface of the telescopic arm. When it is detected that the power is applied, the operation restricting mechanism starts operating based on these signals, and restricts the operation of the hydraulic cylinder for rocking the boom and the hydraulic cylinder for rocking the telescopic arm. In this regulation, each hydraulic cylinder allows the boom and the telescopic arm to swing only in the direction of the excavator, and regulates the operation of swinging the excavator in the opposite direction. When the stress is detected by the upper bending moment sensor, since the telescopic arm is in contact with the inner wall on the opposite side of the excavator inside the dug hole, the telescopic arm swings to the opposite side of the excavator. It is possible to prevent the telescopic arm from being deformed by moving the telescopic arm (the invention according to claim 4).

Further, the telescopic arm body in the movement restricting mechanism of the deep digging machine according to the present invention includes a base arm connected to the end of the boom, a middle arm slidably inserted into the base arm, and a middle arm. And a tip arm slidably inserted into the arm. In this configuration, the telescopic arm is 3
It is composed of two former arms, a middle arm and a front arm, and can be extended in a telescopic manner, so that a deeper hole can be dug (the invention according to claim 5).

In the motion restricting mechanism for a deep digging machine according to the present invention, the telescopic arm body includes a base arm connected to the tip of the boom, a middle arm slidably inserted into the base arm, and a middle arm. The extension sensor can detect that the telescopic arm is extended when extending from the original arm to the middle arm or the distal arm. For this reason, the detection of expansion and contraction of the telescopic arm by the elongation sensor becomes accurate,
The state of the excavator can be reliably determined (the invention according to claim 6).

[Brief description of the drawings]

FIG. 1 is a perspective view showing the appearance of a deep excavator according to an embodiment of the present invention.

FIG. 2 is an explanatory diagram showing a state in which a deep hole W is excavated using a deep excavator according to an embodiment of the present invention.

FIG. 3 is an explanatory diagram showing an arrangement of a hydraulic drive mechanism and various sensors of the deep excavator according to one embodiment of the present invention.

FIG. 4 is an explanatory diagram schematically showing a series of an electric signal system and a hydraulic signal system arranged in the deep excavator according to the embodiment of the present invention.

FIG. 5 is a hydraulic piping diagram showing a configuration of an operation unit disposed inside a deep excavator according to an embodiment of the present invention.

FIG. 6 is a hydraulic piping diagram illustrating a configuration of a drive unit disposed inside a deep excavator according to an embodiment of the present invention.

FIG. 7 is a hydraulic piping diagram showing a configuration of a regulation unit disposed inside a deep excavator according to an embodiment of the present invention.

FIG. 8 is a hydraulic piping diagram showing a configuration of an expansion / contraction restrictor disposed inside a deep excavator according to an embodiment of the present invention.

FIG. 9 is an electric circuit diagram showing a configuration of a situation determination unit disposed inside a deep excavator according to an embodiment of the present invention.

FIG. 10 is a truth table showing a correlation between a discrimination signal of each sensor and each switching valve of the regulation unit when regulating each part of the deep excavator according to the embodiment of the present invention. DESCRIPTION OF SYMBOLS 11 Vehicle body 13 Turning table 14 Boom 15 Hydraulic cylinder 16 Former arm 18 Hydraulic cylinder 20 Middle arm 21 Forearm 22 Telescopic arm body 46 Angle sensor 47 Elongation sensor 48 Lower bending moment sensor 49 Upper bending moment sensor 55 Operation unit 56 Drive unit 57 Regulation Unit 65 Expansion / contraction regulating unit 66 Situation determination unit

Claims (6)

[Claims] 1. A movable vehicle body, a swivel mounted on the upper surface of the vehicle so as to be rotatable in a horizontal direction, and a boom connected to the upper surface of the swivel so as to be swingable up and down. , A telescopic arm that is connected to the end of the boom so as to be swingable up and down, and that can store and extend a plurality of arms inside the telescopic arm, and a tip of the lowermost arm of the telescopic arm In a deep digging machine that is connected to the excavator and comprises a bucket that grabs earth and sand, an extension sensor attached to the telescopic arm body to detect the expansion / contraction state, and a hydraulic pressure attached to the swivel base to rotate the swivel base relative to the vehicle body A motor, a drive oil supply mechanism for pumping the drive oil, an oil amount control mechanism interposed between the hydraulic motor and the drive oil supply mechanism for controlling the amount of drive oil supplied, an extension sensor and an oil amount control mechanism Between When the telescopic arm body is in the extended state, the oil amount control mechanism reduces the flow rate of the drive oil to reduce the rotation speed of the hydraulic motor and the operation control mechanism that decreases the rotation speed of the swivel. A motion control mechanism for a deep excavator, comprising: 2. A movable vehicle body, a swivel mounted on the upper surface of the vehicle so as to be rotatable in a horizontal direction, and a boom connected to the upper surface of the swivel so as to be vertically swingable. , A telescopic arm body which is connected to the end of the boom so as to be swingable up and down, and which can store and extend a plurality of arms therein and expand and contract the length thereof, and a distal end of a lowermost arm of the telescopic arm body In a deep digging machine that is connected to a and excavates a bucket that grabs earth and sand, an extension sensor attached to the telescopic arm body to detect the expansion / contraction state, and an angle sensor attached to the telescopic arm body to detect the inclination angle A hydraulic cylinder interposed between the swivel table and the boom to swing the boom up and down; a hydraulic cylinder interposed between the boom and the telescopic arm to swing the telescopic arm up and down; A hydraulic cylinder provided inside the contraction arm body for expanding and contracting the telescopic arm body, a drive oil supply mechanism for pumping drive oil to each hydraulic cylinder, and a supply oil interposed between each hydraulic cylinder and the drive oil supply mechanism Inputs the oil amount control mechanism that controls the drive oil, and the detection signals from the extension sensor and angle sensor, and the telescopic arm expands,
And, when the telescopic arm body is inclined at a certain angle or more with respect to the vertical, a control signal is output to the oil amount control mechanism to restrict the telescopic arm body to swing only in the vertical direction, A movement regulation mechanism for a deep digging machine, comprising: an operation regulation mechanism for regulating the telescopic arm body to be allowed only in a direction in which the telescopic arm body is reduced. 3. A movable body, a swivel mounted on the upper surface of the body so as to be rotatable in a horizontal direction, and a boom connected to the upper surface of the swivel so as to be vertically swingable. , A telescopic arm body which is connected to the end of the boom so as to be swingable up and down, and which can store and extend a plurality of arms therein and expand and contract the length thereof, and a distal end of a lowermost arm of the telescopic arm body A deep excavator connected to the excavator, the excavator being attached to the telescopic arm and detecting the state of expansion and contraction; and the excavator side of the telescopic arm attached to the telescopic arm. Bending moment sensor that detects the stress applied to the boom, a hydraulic cylinder interposed between the swivel and the boom to swing the boom up and down, and interposed between the boom and the telescopic arm to expand and contract A hydraulic cylinder that swings the arm up and down, a drive oil supply mechanism that pumps drive oil to each hydraulic cylinder, and an oil quantity that controls the drive oil that is interposed between each hydraulic cylinder and the drive oil supply mechanism The control mechanism and the detection signals from the extension sensor and the lower bending moment sensor are input, and when the telescopic arm is extended and stress is applied to the lower side of the telescopic arm, control is performed by the oil amount control mechanism. A movement restricting mechanism for a deep excavator, comprising: an operation restricting mechanism that restricts the telescopic arm body to swing only in a vertical direction by outputting a signal. 4. A movable vehicle body, a swivel mounted on the upper surface of the vehicle so as to be rotatable in a horizontal direction, and a boom connected to the upper surface of the swivel so as to be vertically swingable. , A telescopic arm body which is connected to the end of the boom so as to be swingable up and down, and which can store and extend a plurality of arms therein and expand and contract the length thereof, and a distal end of a lowermost arm of the telescopic arm body A deep excavator, which is connected to the excavator, and which is attached to the telescopic arm body to detect the state of expansion and contraction, and which is attached to the telescopic arm body and opposite to the telescopic arm body excavator. An upper bending moment sensor that detects the stress applied to the side of the side, a hydraulic cylinder that is interposed between the swivel table and the boom to swing the boom up and down, and an interposed between the boom and the telescopic arm A hydraulic cylinder that swings the telescopic arm up and down, a drive oil supply mechanism that pumps drive oil to each hydraulic cylinder, and a drive oil that is interposed between each hydraulic cylinder and the drive oil supply mechanism. Input the detection signals from the extension sensor and the upper bending moment sensor, and when the telescopic arm is extended and stress is applied to the upper side of the telescopic arm, A movement control mechanism for a deep excavator, comprising: an operation control mechanism for outputting a control signal to control the telescopic arm to swing only in a vertical direction. 5. The telescopic arm body includes a base arm connected to a tip of a boom, a middle arm slidably inserted into the base arm, and a front arm slidably inserted into the middle arm. 4. The method according to claim 1, further comprising:
And 5. A motion control mechanism for a deep excavator according to claim 5. 6. The telescopic arm body includes a base arm connected to a tip of a boom, a middle arm slidably inserted into the base arm, and a front arm slidably inserted into the middle arm. The extension sensor is fixed to the former arm, and the extension sensor outputs a detection signal when the middle arm or the tip arm extends from the former arm, wherein the extension sensor outputs a detection signal. 5. A motion control mechanism for a deep excavator according to item 5.