JP2023162740A - Operation device of excavator, and excavator - Google Patents

Abstract

To provide an operation device of an excavator, and an excavator which control the rotary drive of a rotary drive device, and can reduce operation loads on an operation lever.SOLUTION: An operation device for imparting a lever operation signal to a rotary drive control valve 37 of a rotary drive device on the basis of tilting of an operation lever 33 includes a controller 35, an operation detection part 36 for detecting the tilting of the operation lever, and a rotation holding switch 34 arranged in an operator cab independently from the operation lever, wherein the controller interrupts a lever operation signal and imparts an alternative operation signal corresponding to the lever operation signal to the rotary drive control valve when detection signals are simultaneously input from the operation detection part and the rotation holding switch, interrupts the alternative operation signal on the basis of the tilting through a neutral position of the operation lever in a state where the alternative operation signal is imparted, and recovers only the lever operation signal from the interruption state on the basis of the tilting through the neutral position of the operation lever in a state where the lever operation signal and the alternative operation signal are interrupted.SELECTED DRAWING: Figure 4

Description

TECHNICAL FIELD The present invention relates to an operating device for an excavating machine and an excavating machine, and more particularly to an operating device for an excavating machine and an excavating machine that include a rotational drive device that rotationally drives an excavating tool.

2. Description of the Related Art Generally, construction machines equipped with various working devices such as cargo handling equipment and excavation equipment perform desired operations by tilting and operating a control lever on a driver's seat. These operating levers are equipped with a fail-safe function, and when the lever is released from a predetermined operating position, the elastic force of the built-in spring returns it to the neutral position, stopping the operation of the machine. On the other hand, in order to meet the demand for keeping the operating position of the operating lever constant from the viewpoint of convenience, a holding/releasing device that can maintain the tilting position of the operating lever using hydraulic pressure has been proposed. (For example, see Patent Document 1.)

Japanese Patent Application Publication No. 2001-124010

Among various types of construction machinery, excavating machines that work underground require the rotation of the kelly drive to be continuously driven for a long period of time when removing obstacles, for example, so it is difficult to operate it when the rotational drive is maintained. The burden of operating the lever can be reduced. However, since the held state is outside the concept of fail-safe, from a safety perspective, it is necessary not to enter the held state easily, and it is also important that it is easy to return from the held state, and that the return operation is easy. When this is done, it is also required that the rotational drive is brought to a halt quickly.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide an operating device for an excavating machine and an excavating machine that can control the rotational drive of a rotary drive device to reduce the operating burden on the operating lever.

In order to achieve the above object, an operating device for an excavating machine according to the present invention includes a lower traveling body, an upper rotating body rotatably provided on the upper part of the lower traveling body, and an upper rotating body mounted on the upper rotating body and provided inside the lower traveling body. Equipped with an excavating machine comprising a cab defining a driver's cab, a leader erected at the front of the upper revolving body, and a rotary drive device that can be raised and lowered along the leader, the excavator is disposed in the driver's cab. In the operating device that applies a lever operation signal to the rotary drive control valve of the rotary drive device based on the tilting of the operating lever, the controller, an operation detection unit that detects the tilting of the operating lever, and the operating lever include: a rotation holding switch independently disposed in the driver's cab; the operating lever is provided with an elastic member for returning the lever shaft from the tilted position to the neutral position; When the detection signals from the rotation holding switch are simultaneously input, the lever operation signal is cut off, and an alternative operation signal corresponding to the lever operation signal is provided to the rotation drive control valve, and the alternative operation signal is is applied, the alternative operation signal is cut off based on the tilting of the operating lever via the neutral position, and when the lever operating signal and the alternative operating signal are blocked, the operating lever is tilted via the neutral position. Based on this, only the lever operation signal is returned from the cutoff state.

The lever operation signal is a lever operation pressure signal of hydraulic oil flowing through a pilot oil passage, and the pilot oil passage includes a remote control valve that changes the lever operation pressure signal according to the tilting of the operation lever, and a remote control valve that changes the lever operation pressure signal according to the tilting of the operation lever. an electromagnetic control valve provided on the downstream side of the remote control valve, and the operation detection section is a pressure transmitter that detects the lever operation pressure signal in the pilot oil path between the remote control valve and the electromagnetic control valve. The electromagnetic control valve includes an oil passage cutoff valve that cuts off the flow of hydraulic oil from the remote control valve, and a pilot oil passage on the downstream side of the oil passage cutoff valve that communicates with an attached replenishment pilot oil passage. the controller controls the oil passage cutoff valve to shut off the flow of hydraulic oil when detection signals from the pressure transmitter and the rotation holding switch are simultaneously input. At the same time, by controlling the oil passage switching valve to introduce the hydraulic oil flowing through the replenishment pilot oil passage into the downstream pilot oil passage, the rotary drive control valve responds to the lever operation pressure signal. applying an alternative operating pressure signal; in a state in which the alternative operating pressure signal is applied, controlling the oil passage switching valve based on the tilting of the operating lever through the neutral position to cut off the alternative operating pressure signal; The present invention is characterized in that when the lever operation pressure signal and the alternative operation pressure signal are in the cutoff state, only the lever operation pressure signal is returned from the cutoff state based on the tilting of the control lever through the neutral position.

Furthermore, the driver's cabin is divided into two in the left and right width directions by a vertical plane passing through the center of the driver's seat, and the operating lever is installed in one side of the divided interior space, and the rotation holding switch is installed in the other side. The shortest distance between the operating lever and the rotation holding switch is larger than the left-right width dimension of the driver's seat. In addition, the excavating machine of the present invention is characterized by being equipped with the operating device.

According to the present invention, the operating device provided in the excavation machine includes the rotation holding switch arranged independently of the operating lever, and when the detection signals from the operation detection section and the rotation holding switch are simultaneously input to the controller, In addition to cutting off the lever operation signal, an alternative operation signal corresponding to the lever operation signal is given to the rotation drive control valve, so even if the operation lever has returned to the neutral position, it will rotate based on the alternative operation signal. It becomes possible to maintain the rotational state of the drive device, and it is possible to reduce the operating burden on the operating lever.

Furthermore, by placing emphasis on the independence of the rotation holding switch, it is possible to prevent unintentional transition to the rotation holding state, such as by erroneous operation, by inputting simultaneous operations at two locations. On the other hand, after transitioning to the rotation holding state that reflects the operator's operating intention, it is possible to eliminate the involvement of lever operation for rotational drive by simply relying on the elastic return of the operating lever to neutral, and to eliminate the involvement of lever operation for rotational drive, and to This enables stable operation that is not affected by the skill level of the operator.

Furthermore, when the alternative operation signal is applied, the alternative operation signal is cut off based on the tilting of the operation lever through the neutral position, so the stop operation from the rotation holding state can be easily and quickly performed using a single main operation input. Since it can be done easily, it is also safe. In addition, when the lever operation signal and alternative operation signal are cut off, only the lever operation signal is returned from the cutoff state based on the tilting of the operating lever via the neutral position, so the operating lever is tilted at the time of the stop operation. Even if it is, it is possible to smoothly return to the initial state while ensuring safety.

FIG. 2 is a side view of a driver's cab equipped with an operating device according to an embodiment of the present invention. It is also a plan view. It is a figure showing arrangement of a rotation holding switch similarly. It is also a control circuit diagram. FIG. 3 is a control circuit diagram showing a state in which the rotary operation lever is tilted. It is a control circuit diagram showing a state where detection signals from an operation detection section and a rotation holding switch are simultaneously input to the controller. FIG. 3 is a control circuit diagram showing a state in which the rotation control lever is returned to the neutral position in a rotation holding state in which an alternative operation signal is applied to the rotation drive control valve. FIG. 10 is a control circuit diagram showing a state in which the rotary operation lever is tilted from the neutral position and the alternative operation signal is cut off. FIG. 7 is a control circuit diagram showing a state in which the rotary operation lever is returned to the neutral position with the alternative operation signal cut off. 1 is a side view of an excavating machine to which an operating device according to an embodiment of the present invention is applied.

1 to 10 are diagrams in which an operating device according to an embodiment of the present invention is applied to an excavation machine. As shown in FIG. 10, the excavation machine 11 is a multi-purpose excavation specification machine capable of performing various construction works such as casing excavation and ground improvement, and includes an undercarriage 12 equipped with a crawler and a rotating machine on the undercarriage 12. It is equipped with a base machine 14 configured with an upper revolving body 13 that can be provided, a leader 15 erected at the front of the upper revolving body 13, and a undulation cylinder 16 that supports the leader 15 from the rear. . Furthermore, a leader support 17 is provided at the front of the revolving upper structure 13 to support the leader 15 so that it can rise and fall, and a piping support member 18 is provided above the front of the revolving upper structure 13 to support the piping. There is. Furthermore, a driving cab 19 is provided on the right side of the upper revolving structure 13, and a power section 20 equipped with an engine and a hydraulic pump serving as a hydraulic pressure source is provided on the left side.

The leader 15 is formed by connecting a plurality of leader members each having a rectangular tube shape in cross section, and is rotatably attached to a support shaft in the vehicle width direction provided on the leader support 17. At the upper end of the leader 15, there is a top sheave 23 around which the Kelly rope 22 of the Kelly bar 21 is wound, and at the front of the leader 15 there is a Kelly drive 24, which is an example of a rotational drive device for rotationally driving the Kelly bar 21, and a Kelly drive 24 of the Kelly bar 21. A guide device 25 is attached to each. A rack gear 26 is provided at the center of the front surface of the leader 15 as a component of a rack and pinion lifting device, and a pair of left and right guide pipes 27 are provided continuously over the entire length of the leader 15 at the front ends of both sides. This serves as a mounting portion for the drive 24 and guide device 25.

The Kelly drive 24 is configured around a device main body 24a rotatably equipped with a Kelly lever 21, and is provided with a pair of left and right guide gibs 24b, 24b protruding rearward, which slide into guide pipes 27, 27 of the leader 15, and a rack gear. The leader 15 is moved up and down along the front surface thereof by rotationally driving a pair of left and right pinions meshing with the leader 26 by a lifting hydraulic motor (not shown).

The Kelly drive 24 also includes a rotary drive hydraulic motor 24c connected to a speed reduction mechanism in the device main body 24a, and an electromagnetic proportional pressure reducing valve (not shown) attached thereto. The rotational drive hydraulic motor 24c is a swash plate type variable displacement hydraulic motor whose capacity can be changed by changing the tilt angle of the swash plate. The tilt angle of the swash plate, that is, the displacement volume (discharge amount per motor revolution) is adjusted by a regulator. As a result, if the flow rate is constant, the rotary drive hydraulic motor 24c rotates at a higher speed as the displacement volume decreases, and the rotation speed decreases as the displacement volume increases, but the rotational drive hydraulic motor 24c rotates using more hydraulic oil. generates large torque.

Kellyba 21 uses the well-known locking Kellyba equipped with a locking means that can transmit strong pressing force in hard ground, and has a structure (e.g. 4-stage structure) that combines multi-stage Kellyba members, and has a structure that allows it to adjust to the excavation depth. It is formed to expand and contract accordingly. The locking means consists of a plate structure provided in pairs between adjacent Kelly bar members, and by fitting and locking them together, pressing force is applied to the excavation tool attached to the tip (lower end) of the Kelly bar 21. Communicate efficiently.

Here, when the excavation machine 11 is used for the purpose of casing excavation, a casing (not shown) is used as an excavation tool. The casing is connected to the tip of the kely bar 21 via a coupling. As a result, the casing is rotated integrally with the cylindrical body provided concentrically with the rotating shaft of the Kelly drive 24, and by lowering the Kelly drive 24 while rotating the Kelly bar 21, the ground is dug with the excavation bit at the tip of the casing. Excavation or cutting of obstacles such as old foundations.

In order to carry out such casing excavation, a driver's room is defined in the cab 19 in which an operator rides, and there are operating levers, operating pedals, push button switches, touch panels, etc. for running, turning, raising/lowering/rotating the Kelly drive 24, etc. For ease of operation, devices such as a display are placed centrally near the driver's seat, and an operating device including a controller that is electrically connected to these operating devices is installed. There is.

1 to 3 show various operating units arranged in the driver's cab. Here, in order to make the explanation easier to understand, each figure is shown in the opposite direction to the external view in FIG. 10. In FIG. 1, the right side is the front, the left side is the rear, and the The back side shows the left side part, and the near side shows the right side part. When the driver's cabin is divided into two in the left and right width direction (vertical direction in FIG. 2) by a vertical plane S passing through the center of the driver's seat 28, the various operation parts can be operated with the left hand in the left-hand space of the two divided interior spaces. A left-hand operation input section 29 for operation and a right-hand operation input section 30 for right-hand operation are arranged in the right side space side by side with the driver's seat 28 in between.

A ceiling position operation input section 31 and a column position operation input section 32, which are normally operated with the left hand, are arranged on the window frame corresponding to the driver's seat 28 in the left side space. These operation input units 31 and 32 consist of a group of switches arranged in a horizontal or vertical line along the wall surface, and although they are operated less frequently than main operations such as lever operations that operate the machine, Operation input can be easily performed even when the user is seated.

Further, although details will be described later, the shortest distance between the Kelly Drive lift/rotation control lever (two-axis control lever) 33 belonging to the right-hand side operation input section 30 and the rotation holding switch 34 belonging to the column position operation input section 32 is as follows. It is larger than the left and right width dimension of the driver's seat 28. In other words, as can be seen from FIG. 2, the operating lever 33 and the rotation holding switch 34 arranged independently are located outside the area of the driver's seat 28 having the left-right width dimension W in the driver's cabin. Although both hands are required to perform these simultaneous operations while spaced apart from each other, they can be handled in a comfortable posture.

Incidentally, since the excavating machine 11 continuously rotates the Kelly drive 24 for a long time when excavating a casing, for example, when the rotational drive is maintained, the operating burden on the operating lever 33 can be reduced. Therefore, in the operating device, the rotation of the Kelly drive 24 can be held in the holding state according to the operator's selection.

Below, the case where rotation holding operation is performed will be explained with reference to FIGS. 4 to 9. FIG. 4 shows a control circuit for the rotation operation system, which mainly includes a controller 35 that executes a control program, an operation detection section 36 that detects the tilting of the operation lever 33, and a rotation holding switch 34. In the state (lever mode) before shifting the system to the rotation holding mode, a lever operation signal is applied to the rotation drive control valve (rotation direction switching valve) 37 of the Kelly drive 24 based on the tilting of the operation lever 33. It is composed of

The lever operation signal is a pressure signal of hydraulic oil that selectively flows through each of the pilot oil passages 38 and 39 on the normal rotation side and the reverse rotation side in rotational drive. The pilot oil passages 38 and 39 are connected to a remote control valve 40 that changes a lever operation pressure signal (pilot secondary pressure) according to the tilting of the operation lever 33, and an electromagnetic control valve 41 provided downstream of the remote control valve 40. It is equipped with

The operating lever 33 is configured using a remote control valve 40 for two-axis operation, and tilting in the left and right direction is assigned to rotation of the Kelly drive 24, and tilting in the front and back direction (not shown) is assigned to raising and lowering the Kelly drive 24. It is being Further, by adjusting the tilting direction of the operating lever 33, it is possible to push in and pull out the casing in excavation with a combined operation of rotation and elevation, that is, with one-handed operation of one lever. Furthermore, a coil spring 33b is incorporated into the operating lever 33 as an elastic member for returning the lever shaft 33a from the tilted position to the neutral position.

The rotation holding switch 34 is an automatic return type push button switch that is turned on (depressed), and a button operation signal is input to the controller 35 when turned on.

The operation detection unit 36 includes a forward rotation pressure transmitter 36a and a reverse rotation pressure transmitter 36b that detect lever operation pressure signals in detection pilot oil passages 38a and 39a between the remote control valve 40 and the electromagnetic control valve 41. As a result, a lever operation pressure signal generated based on the tilting of the operation lever 33 is converted into an electric signal by the pressure transmitters 36a, 36b and input to the controller 35.

The electromagnetic control valve 41 is operated by a control command from the controller 35, and includes oil passage cutoff valves (lever operation disabled solenoid valves) 42 on the forward and reverse rotation sides that block the flow of hydraulic oil from the remote control valve 40; 43, and the common pilot oil passages 38b, 39b on the downstream side of the oil passage cutoff valves 42, 43 are selectively communicated with the branch oil passages 44a, 44b of the attached replenishment pilot oil passage 44. , 43 to the replenishment pilot oil path 44.

The hydraulic oil flowing through the replenishment pilot oil passage 44 has the same hydraulic pressure source as the hydraulic oil flowing through the remote control valve 40. That is, although not shown, the replenishment pilot oil passage 44 is a branch oil passage obtained by branching off the P line of the pilot pump.

When operating the control circuit configured in this way to perform rotation holding operation, first, the excavating machine 11 is moved to the construction site, and the rotation and lowering operations of the Kelly drive 24 are performed through necessary setup. Here, if we pay attention to the rotational operation, as shown in FIG. Excavation proceeds while the Kelly drive 24 is rotated in the normal rotation direction by obtaining pressure oil from the excavation.

When the lever mode is executed, the controller 35 detects the tilting state of the operating lever 33 using a signal from the forward rotation pressure transmitter 36a, but does not issue a control command to the electromagnetic control valve 41. As a result, the oil passage cutoff valve 42 and the oil passage switching valve 45 are both maintained in a state where the normal rotation side pilot oil passage 38 is communicated (non-energized state), and thereby, the oil passage from the replenishment pilot oil passage 44 is The flow of hydraulic oil is blocked by oil passage switching valves 45 and 46 which are in a closed state.

Here, when the operating lever 33 and the rotation holding switch 34 are simultaneously operated based on the operator's intention to shift to rotation holding operation, the controller 35 has a forward rotation pressure transmitter 36a and a rotation holding switch 34, as shown in FIG. At the same time, the detection signal "ON" from the rotation holding switch 34 is input. Then, the controller 35 switches and controls the normal rotation side oil passage cutoff valve 42 to block the flow of hydraulic oil in the detection pilot oil passage 38a, and also switches and controls the normal rotation side oil passage switching valve 45 to block the flow of hydraulic oil in the detection pilot oil passage 38a. By introducing the hydraulic oil flowing through the passage 44 (branched oil passage 44a) into the common pilot oil passage 38b, an alternative operation pressure signal corresponding to the lever operation pressure signal is applied to the rotational drive control valve 37. At this time, the intermediate pilot oil passage 38c is connected to the T line that returns the hydraulic oil to the tank according to the switching control of the normal rotation side oil passage cutoff valve 42 and the normal rotation side oil passage switching valve 45.

When the rotation holding mode is executed, an alternative operating pressure signal is given as a control command to the rotational drive control valve 37, and the rotational drive of the Kelly drive 24 is continued. Here, as shown in FIG. 7, when the lever operation (left and right direction) is relaxed and the operating lever 33 is returned to the neutral position, the flow of hydraulic oil to the detection pilot oil passage 38a is caused by the closed remote control valve. 40. However, since the alternative operating pressure signal is applied to the rotational drive control valve 37, the rotational state of the Kelly drive 24 is maintained even if the operating lever 33 returns to the neutral position. Further, in this state, the controller 35 receives the detection signal "off" from both the normal rotation pressure transmitter 36a and the rotation holding switch 34.

By the way, while the rotation holding mode is being executed, the user can concentrate on the operation of lowering the Kelly drive 24, but there may be cases where it is desired to exit the rotation holding mode due to the behavior of the machine or the like. In that case, the operating lever 33 is tilted from the neutral position to either the forward rotation side or the reverse rotation side. For example, as shown in FIG. 8, when the operating lever 33 is tilted again toward the forward rotation side (for example, by tilting 3 degrees or more), the lever operation pressure signal generated based on this is transmitted to the controller via the forward rotation pressure transmitter 36a. 35.

At this time, the controller 35 to which the lever operation detection signal "ON" has been input is in the state where the alternative operation pressure signal is applied (FIG. 6), and based on the tilting of the operation lever 33 via the neutral position (FIG. 7), the controller 35 is corrected. The alternative operation pressure signal is cut off by controlling the change side oil passage switching valve 45 (FIG. 8). As a result, no control command is issued to the rotational drive control valve 37, and the rotation (hydraulic drive) of the Kelly drive 24 is immediately stopped.

When the operation lever 33 is in the tilted state (FIG. 8), the flow of hydraulic oil from the remote control valve 40 in the normal rotation side pilot oil passage 38 is blocked by the normal rotation side oil passage isolation valve 42 in the closed state, so that the operation cannot be performed. Even when the lever 33 is placed in the tilted position, the rotation of the Kelly drive 24 remains stopped. Then, when the operation lever 33 is returned to the neutral position almost simultaneously with the rotation of the Kelly drive 24 stopping, or immediately after the rotation has stopped, the flow of hydraulic oil to the detection pilot oil passage 38a is reduced as shown in FIG. , is prevented by the remote control valve 40 in the closed state.

Here, the controller 35 to which the lever operation detection signal "off" has been input from the forward rotation pressure transmitter 36a switches and controls the forward rotation side oil passage cutoff valve 42 to bring the forward rotation side pilot oil passage 38 into communication. to hold. In this way, the system exits the rotation holding mode and transitions (returns) to the lever mode, which is the initial state. At this time, when the lever operation pressure signal and the alternative operation pressure signal are cut off (FIG. 8), the controller 35 moves the lever as shown in FIG. 5 based on the tilting of the operation lever 33 through the neutral position (FIG. 9). Only the operating pressure signal is restored from the cutoff state (FIG. 8). As a result, casing excavation can be advanced by any lever operation by the operator.

As described above, according to the present invention, the operating device provided in the excavating machine 11 includes the rotation holding switch 34 arranged independently of the operating lever 33, and the controller 35 is provided with the rotation holding switch 34 arranged independently of the operating lever 33. When the detection signals are input at the same time, the lever operation signal is cut off and an alternative operation signal corresponding to the lever operation signal is applied to the rotary drive control valve 37, so the operation lever 33 is returned to the neutral position. Even in this case, it is possible to maintain the rotational state of the rotary drive device 24 based on the alternative operation signal, and the operational burden on the operation lever 33 can be reduced.

Further, by placing importance on the independence of the rotation holding switch 34, it is possible to prevent an unintended transition to the rotation holding state, such as an erroneous operation, by inputting simultaneous operations at two locations. On the other hand, after transitioning to the rotation holding state that reflects the operator's operating intention, it is possible to eliminate the involvement of lever operation for rotational drive by simply relying on the elastic return of the operating lever 33 to neutrality, and to eliminate the involvement of lever operation for rotational drive, It becomes possible to appropriately position the lever 33, and stable operation can be performed regardless of the skill level of the operator.

Furthermore, when the alternative operation signal is applied, the alternative operation signal is cut off based on the tilting of the operation lever 33 through the neutral position, so the stop operation from the rotation holding state can be easily and quickly performed using a single main operation input. It is also superior in terms of safety because it can be carried out in a number of ways. In addition, when the lever operation signal and the alternative operation signal are in the blocked state, only the lever operation signal is returned from the blocked state based on the tilting of the operating lever 33 via the neutral position, so that the operating lever is not tilted at the time of the stop operation. Even if the device is in the initial state, it can be smoothly returned to the initial state while ensuring safety.

In addition, since the lever operation signal is the lever operation pressure signal (pilot secondary pressure) of the hydraulic oil flowing in the pilot oil path, it can be incorporated into the conventional hydraulic pilot operation type operating device by new or retrofitting. An operating device with excellent robustness and low cost and easy control can be achieved.

Further, among the interior space divided into two in the left and right width direction by a vertical plane S passing through the center of the driver's seat 28, the operating lever 33 is arranged in one side space and the rotation hold switch 34 is arranged in the other side space. Since the shortest distance between the rotation holding switch 34 and the rotation holding switch 34 is larger than the left-right width dimension W of the driver's seat 28, the rotation holding state is not easily reached. In other words, it is possible to restrict rotation holding operation against the operator's will.

Furthermore, the operating lever 33 is configured for two-axis operation, and tilting in the left and right directions is assigned to the rotation of the Kelly drive 24, and tilting in the front and back direction is assigned to lifting and lowering the Kelly drive 24, so that construction of the excavation machine 11 is efficiently performed. Even when performing complex operations in which the tilting direction of the operating lever 33 is adjusted, pushing and pulling in casing excavation is possible with one-handed operation of one lever, and coordination with rotation holding operation is easily achieved. Can be done.

Note that the present invention is not limited to the above embodiment, and the configuration and arrangement of the operating device can be changed as appropriate depending on the specifications in the driver's cab. In addition, in the embodiment, a hydraulic pilot operating type operating lever was used, but an electrically operating type operating lever may also be used. In this case, the rotary drive control valve is electrically controlled by a controller and used as an operation detection unit. Lever operation signals from the potentiometer can be input directly to the controller. Furthermore, the number of axes of the operating lever is also arbitrary. In addition, although the explanation has been given using casing excavation (obstacle removal work) as an example, the present invention is not limited to this, and can be applied to other construction methods such as ground improvement.

DESCRIPTION OF SYMBOLS 11... Excavation machine, 12... Lower traveling body, 13... Upper rotating body, 14... Base machine, 15... Leader, 16... Luffing cylinder, 17... Leader support, 18... Piping support member, 19... Operator's cab, 20... Power Part, 21...Kelly bar, 22...Kelly rope, 23...Top sheave, 24...Kelly drive, 24a...device body, 24b...guide gib, 24c...hydraulic motor for rotational drive, 25...guide device, 26...rack gear, 27...guide Pipe, 28... Driver's seat, 29... Left hand side operation input section, 30... Right hand side operation input section, 31... Ceiling position operation input section, 32... Support position operation input section, 33... Operation lever, 33a... Lever shaft, 33b ...Coil spring, 34...Rotation holding switch, 35...Controller, 36...Operation detection section, 36a...Forward rotation pressure transmitter, 36b...Reverse rotation pressure transmitter, 37...Rotation drive control valve, 38...Forward rotation side pilot oil passage, 38a... Detection pilot oil path, 38b...Common pilot oil path, 38c...Intermediate pilot oil path, 39...Reverse side pilot oil path, 39a...Detection pilot oil path, 39b...Common pilot oil path, 39c...Intermediate pilot oil path, 40... Remote control valve, 41... Solenoid control valve, 42... Forward rotation side oil passage cutoff valve, 43... Reverse rotation side oil passage isolation valve, 44... Supply pilot oil passage, 44a, 44b... Branch oil passage, 45... Forward rotation side oil passage Switching valve, 46...Reverse side oil passage switching valve

Claims (4)

an undercarriage body; an upper revolving body rotatably provided on the upper part of the lower revolving body; a cab mounted on the upper revolving body and defining a driver's cabin therein; Equipped with an excavating machine equipped with a leader installed upright and a rotary drive device that can be raised and lowered along the leader,
An operating device that applies a lever operation signal to a rotational drive control valve of the rotational drive device based on the tilting of an operating lever arranged in the driver's cab,
controller and
an operation detection unit that detects tilting of the operation lever;
a rotation holding switch disposed in the operator's cab independently of the operating lever;
The operation lever is provided with an elastic member that returns the lever shaft from the tilted position to the neutral position,
The controller is configured to cut off the lever operation signal when the detection signals from the operation detection section and the rotation holding switch are input at the same time, and to send an alternative signal to the rotation drive control valve corresponding to the lever operation signal. Gives an operation signal,
In the state in which the alternative operation signal is applied, the alternative operation signal is cut off based on the tilting of the operation lever through the neutral position;
An operating device characterized in that, when the lever operation signal and the alternative operation signal are in a blocked state, only the lever operation signal is returned from the blocked state based on the tilting of the operating lever through a neutral position. The lever operation signal is a lever operation pressure signal of hydraulic oil flowing in the pilot oil path,
The pilot oil passage includes a remote control valve that changes the lever operation pressure signal according to the tilting of the operation lever, and an electromagnetic control valve provided downstream of the remote control valve,
The operation detection unit is a pressure transmitter that detects the lever operation pressure signal in the pilot oil path between the remote control valve and the electromagnetic control valve,
The electromagnetic control valve includes an oil passage cutoff valve that cuts off the flow of hydraulic oil from the remote control valve, and a pilot oil passage on the downstream side of the oil passage cutoff valve that communicates with an attached replenishment pilot oil passage to switch the oil passage. Consists of an oil passage switching valve,
The controller controls the oil passage cutoff valve to shut off the flow of hydraulic oil and controls the oil passage switching valve when detection signals from the pressure transmitter and the rotation holding switch are input simultaneously. by introducing the hydraulic oil flowing through the replenishment pilot oil passage into the downstream pilot oil passage, providing an alternative operation pressure signal corresponding to the lever operation pressure signal to the rotary drive control valve;
In the state where the alternative operating pressure signal is applied, controlling the oil passage switching valve based on the tilting of the operating lever through the neutral position to cut off the alternative operating pressure signal;
2. In a state where the lever operation pressure signal and the alternative operation pressure signal are cut off, only the lever operation pressure signal is returned from the cutoff state based on tilting of the operating lever through a neutral position. operating device. The driver's cabin is divided into two in the left and right width direction by a vertical plane passing through the center of the driver's seat, and of the two divided interior spaces, the operating lever is arranged in one side space, and the rotation holding switch is arranged in the other side space. death,
3. The operating device according to claim 1, wherein the shortest distance between the operating lever and the rotation holding switch is larger than the left-right width dimension of the driver's seat. An excavation machine comprising the operating device according to claim 1 or 2.

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