Hangzhou Daji

Abstract

To provide a pile driver having an operation device for simultaneously heightening habitability, operability and safety in driving operation.SOLUTION: A pile driver has an operation device imparting a lever operation signal to an operation control circuit, on the basis of tilt operation of operation levers 32a, 33a. The operation device has an operation mode changeover switch 36 switchable to a main operation mode for pile driving work and a sub-operation mode for adjusting inclination of a leader. The operation lever 33a consists of a joystick type lever operated in longitudinal and lateral directions from a neutral position, being gripped by an operator, and in the sub-operation mode, the operation in the longitudinal direction generates a lever operation signal to a leader raising and falling control valve for expanding and shrinking a leader raising and falling cylinder, and the operation in the lateral direction generates a lever operation signal to a leader tilting control valve for expanding and shrinking a leader tilting cylinder. The longitudinal and lateral directions of tilting operation of the operation lever and the longitudinal and lateral directions of swaying of the leader are associated with each other.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a pile driver, and more particularly to a pile driver equipped with an operating device for performing a desired operation by tilting an operating lever. [Background technology]

[0002] A pile driver is known that allows selective operation of the auger and leader with a single operating lever, thereby improving the livability of the operator's cab by saving space by reducing the number of levers (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Utility Model Application Publication No. 6-56141 Summary of the Invention [Problem to be solved by the invention]

[0004] It is already common practice to properly manage the verticality (inclination) of piles during pile construction. Therefore, pile drivers are equipped with operating hydraulic circuits that independently adjust the tilt angles of the leader in the forward / backward and left / right directions. As the number of axes for leader operation increases, the idea of ​​using a common operating lever, as in Patent Document 1, is effective in reducing the number of levers. However, if the hydraulic circuit switching operation is allowed too easily, the risk of operator error increases, and thus satisfactory operability and safety at a practical level have not been achieved until now.

[0005] SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a pile driver equipped with an operating device that can simultaneously improve comfort, operability, and safety during operation. [Means for solving the problem]

[0006] In order to achieve the above object, the pile driver of the present invention comprises a lower traveling body, an upper rotating body rotatably provided on the upper part of the lower traveling body, a cab mounted on the upper rotating body and defining an operator's cab therein, a leader erected at the front of the upper rotating body, an auger that can rise and fall along the leader, a winch that winds up and feeds out a hoisting rope, and an operating device that gives a lever operation signal to an operating control circuit based on tilting operation of an operating lever arranged in the operator's cab, wherein the leader is supported so as to be swingable in forward, backward, left and right directions relative to the upper rotating body, and the tilt of the leader can be adjusted in forward, backward, left and right directions by a leader hoisting cylinder corresponding to the forward and backward direction and a leader tilting cylinder corresponding to the left and right direction. The operating device has an operation mode changeover switch that can be switched between a main operation mode for performing pile driving work and a sub-operation mode for adjusting the tilt of the leader, and the operating lever consists of a joystick-type operating lever that is held by the operator and operated in forward / backward and left / right directions from a neutral position, and in the sub-operation mode, operation in the forward / backward direction generates a lever operation signal to a leader hoisting control valve that extends and retracts the leader hoisting cylinder, and operation in the left / right direction generates a lever operation signal to a leader tilt control valve that extends and retracts the leader tilting cylinder, and the forward / backward and left / right directions in which the operating lever is tilted are respectively associated with the forward / backward and left / right directions in which the leader swings.

[0007] The operation device is characterized by having a notification means for notifying that the operation mode has been switched from the main operation mode to the sub-operation mode. [Effects of the Invention]

[0008] According to the pile driver of the present invention, by switching between the main operation mode and the sub-operation mode using the operation mode selector switch, it is possible to selectively operate two of the operations required for pile driving work, namely, swinging, winch winding up / down, and auger forward / reverse rotation, and two operations required for adjusting the leader inclination, namely, leader hoisting and leader tilting, with a single joystick-type operation lever. Moreover, since the front-rear and left-right directions for tilting the operation lever correspond to the front-rear and left-right directions for swinging the leader, the operation sense of the operator adjusting the leader inclination is matched. In other words, the space gained by reducing the number of operation levers improves occupancy during operation, and at the same time, operability and safety are also improved.

[0009] In addition, since the operating device has a notification means for notifying that it has switched from the main operation mode to the sub-operation mode, the operator can be sure to recognize the state when adjusting the reader tilt, thereby further increasing safety. [Brief explanation of the drawings]

[0010] [Figure 1] 1 is a side view of a pile driver showing an example of an embodiment of the present invention. [Figure 2] FIG. [Figure 3] FIG. [Figure 4] FIG. [Figure 5] FIG. 10 is an explanatory diagram of the operation mode changeover switch. [Figure 6] FIG. 10 is an electrical circuit diagram of the same device having an operation mode changeover switch. [Figure 7] FIG. 2 is a hydraulic circuit diagram of the operating system and the drive system. [Figure 8] FIG. 10 is a hydraulic circuit diagram of an operation system and a drive system showing a modified example of operation mode switching. DETAILED DESCRIPTION OF THE INVENTION

[0011] 1 to 8 are diagrams showing a pile driver of the present invention. As shown in Fig. 1, the pile driver 11 is a dual-purpose machine that can switch between steel pipe pile construction and ground improvement construction, and is equipped with a base machine 14 consisting of a lower traveling body 12 equipped with crawlers and an upper rotating body 13 rotatably mounted on the lower traveling body 12, and a leader 15 erected at the front of the upper rotating body 13. A leader support 16 is also provided at the front of the upper rotating body 13 to support the leader 15 so that it can be raised and lowered. Furthermore, stabilizing jacks 17 are provided at four locations on the front, rear, left, and right of the upper rotating body 13, and a counterweight 18 is mounted at the rear end of the upper rotating body 13 to balance the pile driver 11.

[0012] The leader 15 is made up of multiple leader members detachably connected to one another, and has a top sheave 20 attached to its upper end around which a winch rope (suspension rope) 19 is wound, and a lower guide 21 attached to its lower end to prevent the construction material (for example, a steel pipe pile) from swinging. An auger 22, which is an example of a rotation drive device, is attached to the front of the leader 15 so that it can be raised and lowered. The leader 15 is supported so as to be swingable in the front-rear and left-right directions relative to the upper rotating body 13, and the tilt of the leader 15 can be adjusted in the front-rear and left-right directions by extending and retracting a leader hoisting cylinder 23 corresponding to the front-rear direction (left-right direction in Figure 1) and a leader tilting cylinder 24 corresponding to the left-right direction (direction on the paper in Figure 1).

[0013] The auger 22 is hydraulically driven to rotate and imparts a rotational force to the construction member connected to the output shaft. A lifting chain 27 is stretched between a drive sprocket 25 provided at the lower end of the leader 15 and a driven sprocket 26 provided at the upper end, and both ends of the lifting chain 27 are attached to the top and bottom of the auger 22, respectively, to form a chain-type lifting device. The lifting device hydraulically drives the drive sprocket 25 to rotate and moves the lifting chain 27, which is stretched between the drive sprocket 25 and the driven sprocket 26, in the vertical direction, thereby raising and lowering the auger 22 along the front surface of the leader 15.

[0014] The upper rotating body 13 is equipped with a rotating frame 30 on which an operating cab 28 and an engine power unit as a power unit 29 are mounted. The cab 28 is mounted on the right or left side of the rotating frame 30 depending on the specifications of the pile driver 11. A driver's compartment for the operator is defined within the cab 28, and devices such as operation levers and push button switches for driving the vehicle, rotating the vehicle, and raising and lowering and rotating the auger 22, as well as a touch panel monitor, are concentrated near the driver's seat for ease of operation, and a construction management device electrically connected to these devices is also installed.

[0015] Figures 2 to 6 show the operating devices arranged in the driver's cab. Here, Figure 2 corresponds to the orientation of the pile driver 11 in Figure 1, with the left side representing the front, the right side representing the rear, the far side of the page representing the right side, and the near side representing the left side. The various operating systems can be easily operated while seated in the driver's seat 31. As shown in Figures 3 and 4, the left side of the cabin is equipped with a left-hand operating input unit 32 for operation with the left hand, a right-hand operating input unit 33 for operation with the right hand, and a front-side operating input unit 34 for operation with both hands or one hand, respectively. The front-side operating input unit 34 includes, for example, a monitor 35 positioned at eye level with the operator.

[0016] The various operation input units 32, 33, 34 are provided with known operation levers 32a, 33a, 34a, 34b that can be tilted from a neutral position to a predetermined position. For example, by tilting two left and right travel operation levers 34a, 34b belonging to the front operation input unit 34, each operation lever 32a, 33a, 34a, 34b can perform straight-line travel or turning travel using the left and right crawlers. By tilting the turning / auger raising / lowering operation lever (joystick-type operation lever) 32a belonging to the left operation input unit 32, the upper turning body 13 can be turned left or right and the auger 22 can be raised or lowered. By tilting the winch / auger rotation operation lever (joystick-type operation lever) 33a belonging to the right operation input unit 33, the winch can be wound up or lowered (rope winding or unwinding) and the auger 22 can be rotated forward or backward. In addition, both the slewing / auger lifting / lowering operation lever 32a and the winch / auger rotation operation lever 33a are equipped with a magnet mechanism, and are configured so that only the lever tilting operation, which performs the lifting / lowering operation and forward / reverse rotation operation of the auger 22, can be held in the operating state.

[0017] Here, the pile driver 11 can switch between a main operation mode for performing pile driving work (e.g., auger work) and a sub-operation mode for adjusting the tilt of the leader 15. In the sub-operation mode, for example, the front-rear and left-right directions for tilting the right-side operating lever 33a correspond to the front-rear and left-right directions for swinging the leader 15. As shown in Fig. 5, by operating the operation mode changeover switch 36 belonging to the front operation input unit 34, the pile driver 11 can be selectively switched between the main operation mode, which is winch and auger rotation operation, and the sub-operation mode, which is leader hoisting and tilting operation.

[0018] The correspondence between the forward, backward, left and right directions for tilting the operating lever 33a is, for example, such that the forward direction for performing the winch lowering operation corresponds to raising the leader 15 forward, the backward direction for performing the winch hoisting operation corresponds to lowering the leader 15 backward, the right direction for performing the auger forward rotation operation corresponds to right tilting the leader 15 to the right, and the left direction for performing the auger reverse rotation operation corresponds to left tilting the leader 15 to the left.

[0019] The operation mode changeover switch 36 is a position-holding switch (alternate switch) equipped with a C-contact consisting of one movable contact and two fixed contacts, as shown in the electrical circuit diagram of Fig. 6. One of the two fixed contacts is connected to each solenoid (sol) of four changeover valves 37 interposed in the hydraulic circuit (operation control circuit) of the operation system, as shown in Fig. 7, and the other is connected to a lamp 38 as notification means provided next to the operation mode changeover switch 36, or to a buzzer as notification means provided in the operator's cab, as shown in Fig. 5.

[0020] In the main operation mode for pile driving, that is, when one of the fixed contacts is energized, the solenoids are excited, and the four changeover valves 37 are simultaneously operated (the spools are moved to the right from the position in Figure 7), switching the oil paths. A remote control valve 39 incorporated in the operation lever 33a generates a lever operation pressure signal (operation pilot pressure) to a winch rotation control valve 41, which rotates and drives a winch drive motor 40 of the winch drive mechanism, in accordance with the forward and backward tilting of the operation lever 33a. Furthermore, the remote control valve 39 generates a lever operation pressure signal to auger rotation control valves 43, 44, which rotate and drive an auger drive motor 42 of the auger drive mechanism, in accordance with the left and right tilting of the operation lever 33a.

[0021] On the other hand, in the secondary operation mode for adjusting the tilt of the leader 15, that is, when the fixed contact on the other side is energized, each solenoid is de-energized, operating the four changeover valves 37 (which return to the position in Figure 7 by the elastic force of the built-in springs) and switching the oil passages. Then, in accordance with the forward / backward tilting operation of the operating lever 33a, the remote control valve 39 generates a lever operating pressure signal to the leader hoist control valve 45, which extends and retracts the leader hoist cylinder 23. Furthermore, in accordance with the left / right tilting operation of the operating lever 33a, the remote control valve 39 generates a lever operating pressure signal to the leader tilt control valve 46, which extends and retracts the leader tilt cylinder 24.

[0022] Although not shown, when the leader 15 is tilted horizontally in the secondary operation mode, the pile driver 11 assumes a transport position. In this case, the pile driver 11 is controlled so that a cab interference prevention function is activated. For example, when the leader 15 in the upright position (FIG. 1) is tilted a predetermined angle, an attached limit switch is activated, making it impossible to tilt the leader 15 backward (tilting restricted state). On the other hand, once the transport position is assumed, tilting of the leader 15 is impossible (tilt restricted state). This imposes operating conditions in the secondary operation mode, preventing interference between the cab 28 and the leader 15.

[0023] The following describes how to operate the pile driver 11 configured in this manner to adjust the tilt of the leader 15 in the forward / backward and left / right directions. First, the monitor 35 in the driver's cab displays the current leader tilt angle information acquired by the construction management device as numerical values ​​and images, and the operator adjusts the tilt of the leader 15 based on this visual information.

[0024] When the operation mode changeover switch 36 is switched from winch / auger rotation to leader hoist / tilt (Fig. 5), the switch contacts are switched, and the lamp 38 lights up and the buzzer sounds (audio output) to notify that the operation mode has been switched from the main operation mode to the sub-operation mode. Then, while holding the operation lever 33a, the operator tilts the operation lever 33a forward / backward or left / right based on the leader operation display displayed on the screen of the monitor 35 to adjust the inclination of the leader 15.

[0025] After the leader 15 has been vertically aligned in this way, the operation mode selector switch 36 is switched from leader elevation / tilt to winch / auger rotation to return to the main operation mode, the switch contacts are switched again, the lamp 38 goes out, and the buzzer stops sounding. Then, by tilting the operation lever 33a left or right, a rotational force is applied to the construction member connected to the output shaft of the auger 22, and as the auger 22 descends, the construction member is pressed into the ground while maintaining its verticality.

[0026] As described above, according to the pile driver 11 of the present invention, by switching between the main operation mode and the sub-operation mode using the operation mode selector switch 36, it is possible to selectively operate, with a single joystick-type operation lever 33a, any two operations out of swinging, winching, auger raising / lowering, and rotation required for pile driving work, and two operations of leader hoisting and leader tilting required for adjusting the inclination of the leader 15. Moreover, since the front-rear and left-right directions for tilting the operation lever 33a correspond to the front-rear and left-right directions for swinging the leader 15, the operation sense of the operator adjusting the inclination of the leader 15 is matched. In other words, the space gained by reducing the number of operation levers improves occupancy during operation, and at the same time, operability and safety are also improved.

[0027] In addition, the operating device has a notification means (e.g., lamp 38, buzzer) that notifies that the operating mode has been switched from the main operating mode to the sub-operating mode, so that the operator can be sure to recognize the state when adjusting the tilt of the reader 15, thereby further increasing safety.

[0028] 8 shows a modified example of the pile driver of the present invention. In the following description, the same components as those shown in the above embodiment are designated by the same reference numerals, and detailed description thereof will be omitted.

[0029] In this modified example, the electrical components such as the operation mode selector switch 36, lamp 38, and buzzer of the previous embodiment are retained, but the operation lever in the secondary operation mode is assigned to travel by the left and right crawlers instead of winch / auger rotation. Specifically, the forward direction for forward travel operation of the left travel operation lever 34a is assigned to right tilting, which tilts the leader 15 to the right, and the backward direction for reverse travel operation is assigned to left tilting, which tilts the leader 15 to the left. On the other hand, the forward direction for forward travel operation of the right travel operation lever 34b is assigned to uprighting, which raises the leader 15 forward, and the backward direction for reverse travel operation is assigned to lowering, which tilts the leader 15 backward. Although not shown, the lamp 38 and buzzer are wired to the selector valve solenoid side in the electrical circuit that provides the operation mode selector switch 36.

[0030] In the main operation mode for traveling, the solenoids are de-energized, and the switching positions (positions in Figure 8) of the four selector valves 37 are maintained by the elastic force of the built-in springs. The left remote control valve 47 incorporated in the left traveling operation lever 34a generates a lever operation pressure signal to a left traveling control valve 49 that rotates and drives a left traveling drive motor 48 of the left crawler in accordance with forward and backward tilting of the left traveling operation lever 34a. Furthermore, the right remote control valve 50 incorporated in the right traveling operation lever 34b generates a lever operation pressure signal to a right traveling control valve 52 that rotates and drives a right traveling drive motor 51 of the right crawler in accordance with forward and backward tilting of the right traveling operation lever 34b.

[0031] On the other hand, in the secondary operation mode for adjusting the tilt of the leader 15, each solenoid is excited, and the four changeover valves 37 are simultaneously operated (moving the spool to the right from the position in Figure 8), switching the oil passages. Then, in accordance with the forward / backward tilting operation of the left travel operation lever 34a, the left remote control valve 47 generates a lever operation pressure signal to the leader tilt control valve 46, which extends and retracts the leader tilt cylinder 24. Furthermore, in accordance with the forward / backward tilting operation of the right travel operation lever 34b, the right remote control valve 50 generates a lever operation pressure signal to the leader hoist control valve 45, which extends and retracts the leader hoist cylinder 23.

[0032] In this embodiment configured as above, the lamp 38 and buzzer are activated when adjusting the tilt of the reader 15, thereby enabling the operator to be surely aware of the state, thereby further enhancing safety. Furthermore, in this embodiment, the two independent operating levers 34a, 34b make it easy to perform multiple lever operations in the forward / backward and left / right directions when operating the reader.

[0033] The present invention is not limited to the above-described embodiments. The operation levers in the secondary operation mode can be assigned arbitrarily. For example, the winch and auger rotation can be replaced by swing and auger lift. In each embodiment, when the primary operation is the work system, the leader operation is enabled by de-energizing the switching valve solenoid (the spool returns to its elastic state). On the other hand, when the primary operation is the travel system, the leader operation is enabled by energizing the solenoid. However, this is intended to optimize the operational specifications and is not particularly limited. Furthermore, the operation levers can be tilted diagonally to combine the outputs of multiple axes. In addition, electrical signals can be used as operation signals. Leader operation is essential for transporting the pile driver to the site, and even in this case, a buzzer or other warning is provided, further enhancing safety in combination with the cab interference prevention function. [Explanation of symbols]

[0034] 11...pile driver, 12...lower running body, 13...upper rotating body, 14...base machine, 15...leader, 16...leader support, 17...jack, 18...counterweight, 19...winch rope, 20...top sheave, 21...lower guide, 22...auger, 23...leader derricking cylinder, 24...leader tilting cylinder, 25...drive sprocket, 26...driven sprocket, 27...lifting chain, 28...cab, 29...power unit, 30...swivel frame, 31...operator's seat, 32...left side operation input unit, 32a...swivel / auger lifting operation lever, 33...right side Operation input unit, 33a...winch / auger rotation operation lever, 34...front operation input unit, 34a, 34b...travel operation levers, 35...monitor, 36...operation mode selector switch, 37...selector valve, 38...lamp, 39...remote control valve, 40...winch drive motor, 41...winch rotation control valve, 42...auger drive motor, 43, 44...auger rotation control valve, 45...leader hoist control valve, 46...leader tilt control valve, 47...left remote control valve, 48...left travel drive motor, 49...left travel control valve, 50...right remote control valve, 51...right travel drive motor, 52...right travel control valve

Claims

1. A pile driver comprising: a lower traveling body; an upper rotating body rotatably provided on the upper part of the lower traveling body; a cab mounted on the upper rotating body and defining an operator's cab therein; a leader erected at the front of the upper rotating body; an auger that can rise and fall along the leader; a winch that winds up and feeds out a hoisting rope; and an operating device that gives a lever operating signal to an operating control circuit based on tilting operation of an operating lever located in the operator's cab, The leader is supported so as to be swingable in the front-rear and left-right directions relative to the upper rotating body, and the leader can be tilted and adjusted in the front-rear and left-right directions by a leader hoisting cylinder corresponding to the front-rear direction and a leader tilting cylinder corresponding to the left-right direction, The operating device has an operation mode changeover switch that can be switched between a main operation mode for performing pile driving work and a sub-operation mode for adjusting the inclination of the leader, the operation lever is a joystick-type operation lever that is gripped by an operator and operated in forward / backward and left / right directions from a neutral position, and in the secondary operation mode, operation in the forward / backward direction generates a lever operation signal to a leader hoist control valve that operates to extend or retract the leader hoist cylinder, and operation in the left / right direction generates a lever operation signal to a leader tilt control valve that operates to extend or retract the leader tilt cylinder, A pile driver characterized in that the front, rear, left and right directions in which the operating lever is tilted correspond to the front, rear, left and right directions in which the leader swings.

2. 2. The pile driver according to claim 1, wherein the operating device has a notification means for notifying that the operating mode has been switched from the main operating mode to the sub-operating mode.

Images