JP2012102493A

JP2012102493A - Pile driver

Info

Publication number: JP2012102493A
Application number: JP2010250423A
Authority: JP
Inventors: Tokuo Murate; 徳夫村手; Masami Kiriyama; 昌巳桐山; Hideaki Nasu; 英彰那須
Original assignee: Nippon Sharyo Ltd
Current assignee: Nippon Sharyo Ltd
Priority date: 2010-11-09
Filing date: 2010-11-09
Publication date: 2012-05-31
Anticipated expiration: 2030-11-09
Also published as: JP5566264B2

Abstract

PROBLEM TO BE SOLVED: To provide a pile driver that can lift and lower a rotary drive unit at a high speed with a simple structure, without installing a large-volume hydraulic pump for lifting and lowering the rotary drive unit.SOLUTION: A pile driver comprises: a hydraulic motor 20 for lifting/lowering and a hydraulic pump 33 for lifting/lowering that lift and lower a rotary drive unit along a leader; and a hydraulic motor 22 for rotation and hydraulic pumps 32a, 32b for rotation that rotationally drive a working rod mounted on the rotary drive unit. A hydraulic pump whose volume is larger than that of the hydraulic pump for lifting/lowering is installed as a hydraulic pump for rotation. In the middle of a pathway 41 for rotation that supplies hydraulic oil from the hydraulic pump for rotation to the hydraulic motor for rotation, a pathway 42 for lifting/lowering at high speed that supplies hydraulic oil discharged from the hydraulic pump for rotation to the hydraulic motor for lifting/lowering and a lifting/lowering speed changeover valve 43 that supplies hydraulic oil discharged from the hydraulic pump for rotation to the hydraulic motor for lifting/lowering are provided.

Description

本発明は、杭打機に関し、詳しくは、回転駆動装置をリーダに沿って昇降させる昇降用油圧モータと、回転駆動装置に装着した作業ロッドを回転させる回転用油圧モータとを備えた杭打機に関する。 The present invention relates to a pile driving machine, and more particularly, a pile driving machine including a lifting hydraulic motor that moves a rotary drive device up and down along a leader and a rotary hydraulic motor that rotates a work rod attached to the rotary drive device. About.

建設現場における杭打ち作業や地盤改良作業には、ベースマシンに立設したリーダに沿って昇降するオーガドライブやスクリュー駆動装置などの回転駆動装置にロッドやスクリューシャフトなど（以下、これらをまとめて作業ロッドという。）を装着し、回転駆動装置に設けた回転用油圧モータで作業ロッドを回転駆動するとともに、昇降用油圧モータで回転駆動装置をリーダに沿って昇降させることにより所定の作業を行う杭打機が用いられている。 For pile driving work and ground improvement work at construction sites, rods and screw shafts, etc. (hereinafter collectively referred to as rotary drive devices such as auger drives and screw drive devices that move up and down along the leader standing on the base machine) A pile that mounts a rod and rotates a work rod with a rotation hydraulic motor provided in the rotation drive device, and performs a predetermined operation by moving the rotation drive device up and down along a leader with a lifting hydraulic motor. A hitting machine is used.

このような杭打機でリーダより長い作業ロッドを使用する場合は、最初に作業ロッドの上下方向中間部を回転駆動装置で保持し、回転用油圧モータで作業ロッドを回転させながら、昇降用油圧モータで回転駆動装置をリーダに沿って下降させることにより、掘削作業や地盤改良作業を行う。回転駆動装置がリーダの下端に到達したときには、回転用油圧モータ及び昇降用油圧モータを停止して作業を一時中断し、リーダの下端に設けた下部チャックに作業ロッドを保持させるとともに回転駆動装置に設けた上部チャックによる作業ロッドの保持を解除し、昇降用油圧モータで回転駆動装置をリーダに沿って上昇させ、作業ロッドの上部を上部チャックで保持するとともに、下部チャックによる作業ロッドの保持を解除した後、回転用油圧モータ及び昇降用油圧モータを作動させて前記作業を再開するようにしている。 When using a working rod that is longer than the leader in such a pile driver, first hold the vertical intermediate portion of the working rod with a rotation drive device, rotate the work rod with the rotation hydraulic motor, Excavation work and ground improvement work are performed by lowering the rotational drive device along the leader with a motor. When the rotation drive device reaches the lower end of the reader, the rotation hydraulic motor and the elevation hydraulic motor are stopped to temporarily suspend the work, and the work rod is held by the lower chuck provided at the lower end of the reader and the rotation drive device Release the holding of the work rod by the upper chuck, lift the rotary drive device along the leader with the lifting hydraulic motor, hold the upper part of the work rod by the upper chuck, and release the holding of the work rod by the lower chuck Thereafter, the rotation hydraulic motor and the lifting hydraulic motor are actuated to resume the operation.

また、作業ロッドを地中から抜き取る際にも、作業ロッドの上部を保持した回転駆動装置をリーダの上端まで上昇させた後、作業ロッドの回転を一時停止して作業ロッドの保持を解除した回転駆動装置をリーダの下端まで下降させてから、作業ロッドを保持した回転駆動装置を再びリーダの上端まで上昇させる操作を繰り返している。このように、リーダより長い作業ロッドを使用する場合は、回転駆動装置を昇降させる操作を繰り返して所定の作業を行う必要があった（例えば、特許文献１参照。）。 Also, when pulling out the work rod from the ground, after rotating the rotation drive device holding the upper part of the work rod to the upper end of the leader, the rotation of the work rod is temporarily stopped to release the work rod. After the drive device is lowered to the lower end of the reader, the operation of raising the rotary drive device holding the work rod to the upper end of the reader is repeated. As described above, when a work rod longer than the leader is used, it is necessary to perform a predetermined work by repeating the operation of raising and lowering the rotary drive device (see, for example, Patent Document 1).

特開２００２−８８７５５号公報JP 2002-88755 A

作業ロッドを回転させながら回転駆動装置をリーダに沿って昇降させる作業は、地盤の状況に応じてあらかじめ設定された回転速度及び昇降速度で行われる。一方、作業を一時中断して作業ロッドの保持を解除した回転駆動装置を昇降させる時間は無駄な待ち時間であり、できるだけ高速で回転駆動装置を昇降させることが望ましい。このため、昇降用油圧モータに作動油を供給する油圧ポンプとして、作業時に必要な油量より多い油量を供給できる油圧ポンプを設置し、作業中断時の回転駆動装置の昇降を作業時に比べて高速で行えるようにしたものもあるが、満足できる昇降速度を得るためには、高価な大容量の油圧ポンプを設置しなければならず、これを駆動するためにエンジンも大型化し、配管の口径も大きくしなければならないなど、杭打機の製造コストや運転コストなどが大幅に上昇してしまうという問題があった。 The work of raising and lowering the rotary drive device along the reader while rotating the work rod is performed at a rotation speed and a raising / lowering speed set in advance according to the condition of the ground. On the other hand, the time for raising and lowering the rotary drive device that has temporarily suspended the work and released the holding of the work rod is a useless waiting time, and it is desirable to raise and lower the rotary drive device as fast as possible. For this reason, as a hydraulic pump that supplies hydraulic oil to the lifting hydraulic motor, a hydraulic pump that can supply a larger amount of oil than necessary at the time of operation is installed, and the rotation drive device at the time of work interruption is raised and lowered compared to the work Some of them can be operated at high speed, but in order to obtain a satisfactory lifting speed, an expensive large capacity hydraulic pump must be installed. However, there is a problem that the manufacturing cost and operating cost of the pile driving machine greatly increase.

そこで本発明は、回転駆動装置の昇降用として大容量の油圧ポンプを設置することなく、簡単な構成で回転駆動装置を高速で昇降させることができる杭打機を提供することを目的としている。 Accordingly, an object of the present invention is to provide a pile driving machine capable of moving the rotary drive device up and down at high speed with a simple configuration without installing a large capacity hydraulic pump for raising and lowering the rotary drive device.

上記目的を達成するため、本発明の杭打機は、ベースマシンに立設したリーダに沿って昇降可能に設けられた回転駆動装置と、該回転駆動装置を前記リーダに沿って昇降させるための昇降用油圧モータと、該昇降用油圧モータに作動油を供給する昇降用油圧ポンプと、前記回転駆動装置に装着した作業ロッドを回転駆動するための回転用油圧モータと、該回転用油圧モータに作動油を供給する回転用油圧ポンプとを備えた杭打機において、前記回転用油圧ポンプとして前記昇降用油圧ポンプより大容量の油圧ポンプを設置し、回転用油圧ポンプから回転用油圧モータに作動油を供給する経路の途中に、回転用油圧ポンプから吐出された作動油を前記昇降用油圧モータに供給する経路を設けるとともに、回転用油圧ポンプから吐出された作動油を前記昇降用油圧モータに供給する昇降速度切替弁を設けたことを特徴とし、さらに、前記昇降用油圧モータの過回転を防止する手段を備えていることを特徴としている。 In order to achieve the above object, a pile driving machine according to the present invention is provided with a rotary drive device that can be moved up and down along a leader standing on a base machine, and for raising and lowering the rotary drive device along the leader. An elevating hydraulic motor, an elevating hydraulic pump for supplying hydraulic oil to the elevating hydraulic motor, a rotating hydraulic motor for rotationally driving a work rod attached to the rotation driving device, and the rotating hydraulic motor In a pile driving machine equipped with a rotating hydraulic pump that supplies hydraulic oil, a hydraulic pump having a larger capacity than the lifting hydraulic pump is installed as the rotating hydraulic pump, and the rotating hydraulic pump operates from the rotating hydraulic pump. A path for supplying hydraulic oil discharged from the rotary hydraulic pump to the lifting hydraulic motor is provided in the middle of the path for supplying oil, and the hydraulic oil discharged from the rotary hydraulic pump is provided. Characterized in that a lifting speed switching valve for supplying the hydraulic motor the lift, further characterized in that it comprises means for preventing overspeed of the hydraulic motor for the elevation.

本発明の杭打機によれば、例えば掘削作業を一時中断して回転駆動装置をリーダの下端から上端に上昇させる際に、昇降速度切替弁を、回転用油圧モータに作動油を供給する経路から昇降用油圧モータに作動油を供給する経路に切り替えることにより、大容量の回転用油圧ポンプから吐出された大量の作動油を昇降用油圧モータに供給することができるので、昇降用油圧モータを高速で回転させて回転駆動装置を高速で上昇させることができ、作業中断時間を短縮して作業効率を向上させることができる。また、昇降用油圧モータの過回転を防止する手段を設けておくことにより、昇降用油圧モータの過回転に起因する不都合から昇降用油圧モータなどを保護することができる。 According to the pile driving machine of the present invention, for example, when the excavation operation is temporarily interrupted and the rotation drive device is raised from the lower end of the reader to the upper end, the elevating speed switching valve is supplied to the hydraulic oil motor for rotation. By switching to a path for supplying hydraulic oil to the lifting hydraulic motor, a large amount of hydraulic oil discharged from a large-capacity rotary hydraulic pump can be supplied to the lifting hydraulic motor. The rotational drive device can be raised at a high speed by rotating at a high speed, and the work interruption time can be shortened to improve the work efficiency. In addition, by providing means for preventing over-rotation of the lifting hydraulic motor, the lifting hydraulic motor and the like can be protected from inconvenience caused by the over-rotation of the lifting hydraulic motor.

本発明の杭打機の一形態例を示す油圧回路図である。It is a hydraulic circuit diagram which shows one example of a pile driver of this invention. リーダより長い作業ロッドを使用して地盤改良作業を行っている杭打機の一例を示す説明図である。It is explanatory drawing which shows an example of the pile driving machine which is performing the ground improvement work using the working rod longer than a leader.

本形態例に示す杭打機１１は、クローラを備えた下部走行体１２と、該下部走行体１２上に旋回可能に設けられた上部旋回体１３とで構成されたベースマシン１４と、上部旋回体１３の前部に設けられたフロントブラケット１５に起伏可能に設けられたリーダ１６と、該リーダ１６を後方から支持する起伏シリンダ１７と、前記リーダ１６に昇降可能に設けられた回転駆動装置１８と、該回転駆動装置１８を昇降用チェーン１９を介して昇降させるための昇降用油圧モータ２０と、回転駆動装置１８に装着した作業ロッド２１を回転駆動するための回転用油圧モータ２２と、回転駆動装置１８で作業ロッド２１を保持するための上部チャック２３と、リーダ１６の下部で作業ロッド２１を保持するための下部チャック２４とを備えており、運転室２５を備えた上部旋回体１３内に、油圧ポンプやコントロール弁などを備えた油圧ユニットと、前記油圧ポンプを駆動するためのエンジンなどが収容されている。また、作業ロッド２１の上下方向中間部と上端部には、回転駆動装置１８による回転力を伝達する中間角軸部２１ａと上部角軸部２１ｂとが設けられるとともに、上部チャック２３や下部チャック２４によって作業ロッド２１を保持するための中間チャック部２１ｃと上部チャック部２１ｄとが設けられている。 The pile driving machine 11 shown in the present embodiment includes a base machine 14 composed of a lower traveling body 12 provided with a crawler, and an upper revolving body 13 provided on the lower traveling body 12 so as to be able to swivel, and an upper turning A leader 16 provided on the front bracket 15 provided at the front of the body 13 so as to be raised and lowered, a raising and lowering cylinder 17 supporting the leader 16 from the rear, and a rotary drive device 18 provided on the leader 16 so as to be movable up and down. A lifting hydraulic motor 20 for lifting and lowering the rotation driving device 18 via the lifting chain 19, a rotation hydraulic motor 22 for rotating the work rod 21 mounted on the rotation driving device 18, and a rotation An upper chuck 23 for holding the work rod 21 by the driving device 18 and a lower chuck 24 for holding the work rod 21 at the lower part of the reader 16 are provided. In the upper slewing body 13 having a chamber 25, a hydraulic unit with a hydraulic pump and control valves, such as an engine for driving the hydraulic pump is accommodated. Further, an intermediate angular shaft portion 21 a and an upper angular shaft portion 21 b for transmitting a rotational force by the rotation driving device 18 are provided at the intermediate portion and the upper end portion in the vertical direction of the work rod 21, and the upper chuck 23 and the lower chuck 24. Thus, an intermediate chuck portion 21c and an upper chuck portion 21d for holding the work rod 21 are provided.

図１に示すように、前記昇降用油圧モータ２０や回転用油圧モータ２２に作動油を供給するための油圧回路は、主要な構成要素として、油圧ポンプ駆動用のエンジン３１と、前記回転用油圧モータ２２に作動油を供給する一対の可変容量型の低速回転用油圧ポンプ３２ａ及び高速回転用油圧ポンプ３２ｂと、前記昇降用油圧モータ２０に作動油を供給する昇降用油圧ポンプ３３と、オイルクーラ用油圧ポンプ３４と、パイロット用油圧ポンプ３５と、両回転用油圧ポンプ３２ａ，３２ｂから回転用油圧モータ２２に供給する作動油の流れをそれぞれ制御する回転制御用コントロール弁３６ａ，３６ｂと、昇降用油圧ポンプ３３から昇降用油圧モータ２０に供給する作動油の流れを制御する昇降制御用コントロール弁３７とを備えるとともに、その他、これらを接続する配管経路、上部チャック２３や下部チャック２４を作動させるチャック回路などを、従来の一般的な杭打機の油圧回路と同様に備えており、前記両回転用油圧ポンプ３２ａ，３２ｂと前記昇降用油圧ポンプ３３とは、地盤改良作業を含む各種作業中における前記回転用油圧モータ２２が必要とする回転数（出力）と、昇降用油圧モータ２０が必要とする回転数（出力）との関係から、両回転用油圧ポンプ３２ａ，３２ｂには、昇降用油圧ポンプ３３に比べて吐出量の多い大容量の油圧ポンプが用いられている。 As shown in FIG. 1, a hydraulic circuit for supplying hydraulic oil to the lifting hydraulic motor 20 and the rotating hydraulic motor 22 includes, as main components, an engine 31 for driving a hydraulic pump, and the rotating hydraulic pressure. A pair of variable displacement low-speed rotation hydraulic pumps 32 a and 32 b for supplying hydraulic oil to the motor 22, a lift hydraulic pump 33 for supplying hydraulic oil to the lift hydraulic motor 20, and an oil cooler Hydraulic pump 34, pilot hydraulic pump 35, rotation control valves 36 a and 36 b for controlling the flow of hydraulic oil supplied from both rotary hydraulic pumps 32 a and 32 b to rotary hydraulic motor 22, and lift An elevating control valve 37 for controlling the flow of hydraulic oil supplied from the hydraulic pump 33 to the elevating hydraulic motor 20; In addition, a piping path for connecting them, a chuck circuit for operating the upper chuck 23 and the lower chuck 24, and the like are provided in the same manner as a hydraulic circuit of a conventional general pile driving machine, and the double-rotation hydraulic pump 32a is provided. 32b and the lifting hydraulic pump 33 are the number of rotations (output) required by the rotating hydraulic motor 22 during various operations including ground improvement work, and the number of rotations required by the lifting hydraulic motor 20 ( In relation to the output), a large-capacity hydraulic pump having a larger discharge amount than the lifting hydraulic pump 33 is used for the both-rotation hydraulic pumps 32a and 32b.

そして、本形態例では、前記油圧回路において、高速回転用油圧ポンプ３２ｂから回転制御用コントロール弁３６ｂを介して回転用油圧モータ２２に作動油を供給する回転用経路４１の途中の回転制御用コントロール弁３６ｂの上流側で、高速回転用油圧ポンプ３２ｂから吐出された作動油を前記昇降用油圧モータ２０に供給する高速昇降用経路４２を分岐させるとともに、回転用経路４１と高速昇降用経路４２との分岐点に、高速回転用油圧ポンプ３２ｂから吐出された作動油を、前記回転用経路４１と前記高速昇降用経路４２とのいずれか一方の経路に切替供給するための昇降速度切替用コントロール弁４３を設けている。 In this embodiment, in the hydraulic circuit, the control for rotation control in the middle of the rotation path 41 for supplying the hydraulic oil to the rotation hydraulic motor 22 from the high-speed rotation hydraulic pump 32b via the rotation control valve 36b. On the upstream side of the valve 36b, a high-speed lifting path 42 for supplying hydraulic oil discharged from the high-speed rotating hydraulic pump 32b to the lifting hydraulic motor 20 is branched, and a rotation path 41 and a high-speed lifting path 42 are provided. Ascending / descending speed switching control valve for switching and supplying hydraulic oil discharged from the high speed rotating hydraulic pump 32b to one of the rotating path 41 and the high speed elevating path 42 43 is provided.

このような油圧回路を備えた杭打機１１でリーダ１６の約２倍の長さを有する作業ロッド２１を使用して地盤改良作業を行う際には、まず、エンジン３１を作動させて各ポンプを駆動するとともに、リーダ１６の上端に上昇させた回転駆動装置１８の回転駆動部に作業ロッド２１を挿通するとともに、作業ロッド２１の中間チャック部２１ｃを回転駆動装置１８の上部チャック２３で保持した状態とする。このとき、作業ロッド２１の先端（下端）に装着されている掘削撹拌ヘッド２１ｅは地面より上にあり、杭打機１１は、施工場所への走行や上部旋回体１３の旋回が可能な状態となっている。 When the ground improvement work is performed using the work rod 21 having a length about twice that of the leader 16 in the pile driving machine 11 having such a hydraulic circuit, first, the engine 31 is operated to turn on each pump. And the work rod 21 is inserted into the rotation drive portion of the rotation drive device 18 raised to the upper end of the reader 16, and the intermediate chuck portion 21 c of the work rod 21 is held by the upper chuck 23 of the rotation drive device 18. State. At this time, the excavation and stirring head 21e attached to the tip (lower end) of the work rod 21 is above the ground, and the pile driving machine 11 is in a state in which it can travel to the construction site and turn the upper swing body 13. It has become.

施工場所において、昇降速度切替用コントロール弁４３を回転用油圧モータ２２に作動油を供給する状態（中立状態）に切り替え、高速回転用油圧ポンプ３２ｂから回転用経路４１の上流側経路４１ａに吐出された作動油を、昇降速度切替用コントロール弁４３を通過させて回転制御用コントロール弁３６ｂから回転用油圧モータ２２に供給する状態とし、回転制御用コントロール弁３６ａ，３６ｂを操作して両回転用油圧ポンプ３２ａ，３２ｂから供給される作動油によって回転駆動装置１８の回転用油圧モータ２２を作動させ、作業ロッド２１を所定の回転速度で回転させるとともに、昇降制御用コントロール弁３７を操作して昇降用油圧ポンプ３３から吐出された作動油を、昇降用経路４４を介して昇降用油圧モータ２０の正回転側に供給し、昇降用チェーン１９を介して回転駆動装置１８をリーダ１６に沿って所定速度で下降させる。同時に、図示しないバッチャプラントから供給される地盤改良剤を作業ロッド２１内の流路を通して掘削撹拌ヘッド２１ｅから地中に注入し、回転しながら下降している掘削撹拌ヘッド２１ｅで掘削した土砂と地盤改良剤とを撹拌混合する。また、回転用油圧モータ２２に供給する作動油を、必要に応じて低速回転用油圧ポンプ３２ａのみから、あるいは、両回転用油圧ポンプ３２ａ，３２ｂの双方からを選択することによって作業ロッド２１の回転数をあらかじめ設定された回転数に調節する。また、回転駆動装置１８の下降速度も、あらかじめ設定された下降速度に制御する。 At the construction site, the control valve 43 for switching the ascending / descending speed is switched to a state (neutral state) in which hydraulic oil is supplied to the rotating hydraulic motor 22 and discharged from the high-speed rotating hydraulic pump 32b to the upstream path 41a of the rotating path 41. The hydraulic fluid passed through the elevating speed switching control valve 43 is supplied to the rotation hydraulic motor 22 from the rotation control control valve 36b, and the rotation control control valves 36a and 36b are operated to operate both rotation hydraulic pressures. The hydraulic oil 22 supplied from the pumps 32a and 32b operates the rotary hydraulic motor 22 of the rotary drive device 18 to rotate the work rod 21 at a predetermined rotational speed, and the lift control control valve 37 is operated to move up and down. The hydraulic oil discharged from the hydraulic pump 33 is moved to the positive rotation side of the lifting hydraulic motor 20 via the lifting path 44. Feeding, and is lowered at a predetermined speed a rotational drive device 18 along the reader 16 via the lifting chains 19. At the same time, a soil conditioner supplied from a batcher plant (not shown) is injected into the ground from the excavation agitation head 21e through the flow path in the work rod 21, and the earth and sand excavated by the excavation agitation head 21e that is descending while rotating. Stir and mix with the improver. In addition, the working oil supplied to the rotating hydraulic motor 22 can be rotated by selecting only the low speed rotating hydraulic pump 32a or both rotating hydraulic pumps 32a and 32b as required. Adjust the number to a preset number of revolutions. Further, the descending speed of the rotary drive device 18 is also controlled to a preset descending speed.

図２（ａ）に示すように、回転駆動装置１８がリーダ１６の下端に達したら、回転制御用コントロール弁３６ａ，３６ｂ及び昇降制御用コントロール弁３７を停止状態（中立状態）とし、作業ロッド２１の回転及び回転駆動装置１８の下降を停止して作業を一時中断する。そして、作業ロッド２１の保持を回転駆動装置１８の上部チャック２３から下部チャック２４に切り替えた後、昇降速度切替用コントロール弁４３を操作し、高速回転用油圧ポンプ３２ｂから前記上流側経路４１ａに吐出された作動油を昇降速度切替用コントロール弁４３によって前記高速昇降用経路４２に供給する。これにより、高速回転用油圧ポンプ３２ｂから昇降用油圧モータ２０の逆回転方向に大量の作動油が供給され、昇降用油圧モータ２０が高速で逆回転することにより、作業ロッド２１の保持を解除した回転駆動装置１８をリーダ１６に沿って迅速に上昇させる。 As shown in FIG. 2A, when the rotation driving device 18 reaches the lower end of the reader 16, the rotation control control valves 36a and 36b and the lift control valve 37 are stopped (neutral state), and the work rod 21 The rotation and the descent of the rotation drive device 18 are stopped, and the operation is temporarily suspended. Then, after the holding of the work rod 21 is switched from the upper chuck 23 to the lower chuck 24 of the rotation drive device 18, the lifting speed switching control valve 43 is operated and discharged from the high-speed rotation hydraulic pump 32b to the upstream path 41a. The supplied hydraulic oil is supplied to the high-speed lifting path 42 by the lifting speed switching control valve 43. As a result, a large amount of hydraulic oil is supplied in the reverse rotation direction of the lifting hydraulic motor 20 from the high-speed rotating hydraulic pump 32b, and the holding of the work rod 21 is released by the reverse rotation of the lifting hydraulic motor 20 at a high speed. The rotary drive device 18 is quickly raised along the reader 16.

このように、高速回転用油圧ポンプ３２ｂから吐出された作動油の経路を、昇降速度切替用コントロール弁４３によって回転用経路４１から高速昇降用経路４２に切り替え、昇降用油圧ポンプ３３に比べて大容量の高速回転用油圧ポンプ３２ｂから吐出された大量の作動油を昇降用油圧モータ２０に供給することにより、昇降用油圧ポンプ３３から昇降用経路４４を介して作動油を供給する場合に比べて昇降用油圧モータ２０を高速で回転させることができ、回転駆動装置１８の上昇速度を大幅に向上させることができる。例えば、昇降用油圧ポンプ３３の吐出量に対して高速回転用油圧ポンプ３２ｂの吐出量が２倍のときには、回転駆動装置１８を２倍の速度で上昇させることが可能である。 In this way, the path of the hydraulic oil discharged from the high-speed rotation hydraulic pump 32 b is switched from the rotation path 41 to the high-speed lift path 42 by the lift speed switching control valve 43, which is larger than the lift hydraulic pump 33. By supplying a large amount of hydraulic oil discharged from the large-capacity high-speed rotation hydraulic pump 32 b to the lifting hydraulic motor 20, the hydraulic oil is supplied from the lifting hydraulic pump 33 via the lifting path 44. The elevating hydraulic motor 20 can be rotated at a high speed, and the ascent speed of the rotary drive device 18 can be greatly improved. For example, when the discharge amount of the high-speed rotation hydraulic pump 32b is double the discharge amount of the lifting hydraulic pump 33, the rotation drive device 18 can be raised at a double speed.

図２（ｂ）に示すように、高速回転用油圧ポンプ３２ｂを利用して回転駆動装置１８をリーダ１６の上端まで上昇させた後、作業ロッド２１の保持を下部チャック２４から上部チャック２３に切り替えて回転駆動装置１８で作業ロッド２１の上部を保持した後、昇降速度切替用コントロール弁４３を回転用経路４１に作動油を供給する位置に戻してから、前記同様に、回転制御用コントロール弁３６ａ，３６ｂを操作して両回転用油圧ポンプ３２ａ，３２ｂからの作動油を回転用経路４１を介して回転用油圧モータ２２に供給することにより作業ロッド２１を回転させながら、昇降制御用コントロール弁３７を操作して昇降用油圧ポンプ３３からの作動油を昇降用経路４４を介して昇降用油圧モータ２０の正回転方向に供給し、回転駆動装置１８をリーダ１６に沿って下降させる。 As shown in FIG. 2 (b), the rotary drive device 18 is raised to the upper end of the reader 16 using the high-speed rotation hydraulic pump 32 b, and then the holding of the work rod 21 is switched from the lower chuck 24 to the upper chuck 23. After the upper part of the work rod 21 is held by the rotation driving device 18, the elevating speed switching control valve 43 is returned to the position where the hydraulic oil is supplied to the rotation path 41, and then, similarly to the above, the rotation control control valve 36a. , 36b is operated to supply hydraulic oil from the rotary hydraulic pumps 32a, 32b to the rotary hydraulic motor 22 through the rotary path 41, and the work rod 21 is rotated, while the lift control valve 37 is controlled. To supply hydraulic oil from the lifting hydraulic pump 33 via the lifting path 44 in the forward rotation direction of the lifting hydraulic motor 20, and a rotation driving device 8 is lowered along the leader 16.

あらかじめ設定された深度まで掘削した後、回転制御用コントロール弁３６ａ，３６ｂを操作して両回転用油圧ポンプ３２ａ，３２ｂから回転用油圧モータ２２に作動油を供給して作業ロッド２１を所定の回転数で回転させながら、昇降制御用コントロール弁３７を逆方向に操作して昇降用油圧ポンプ３３から昇降用油圧モータ２０の逆回転方向に作動油を供給し、昇降用油圧モータ２０を逆回転させて回転駆動装置１８をリーダ１６に沿って所定の上昇速度で上昇させ、作業ロッド２１を地中から引き抜いていく。 After excavation to a preset depth, the rotation control valves 36a and 36b are operated to supply hydraulic oil to the rotation hydraulic motor 22 from both rotation hydraulic pumps 32a and 32b to rotate the work rod 21 to a predetermined rotation. By operating the control valve 37 for lifting control in the reverse direction while rotating by a number, hydraulic fluid is supplied in the reverse rotation direction of the lifting hydraulic motor 20 from the lifting hydraulic pump 33 to reversely rotate the lifting hydraulic motor 20. Then, the rotary drive device 18 is raised along the leader 16 at a predetermined rising speed, and the work rod 21 is pulled out from the ground.

図２（ｂ）に示すように、回転駆動装置１８がリーダ１６の上端まで上昇したら、回転制御用コントロール弁３６ａ，３６ｂ及び昇降制御用コントロール弁３７を停止状態にして作業ロッド２１の回転及び回転駆動装置１８の上昇を停止して作業を一時中断するとともに、作業ロッド２１の保持を上部チャック２３から下部チャック２４に切り替え、昇降速度切替用コントロール弁４３を操作して高速回転用油圧ポンプ３２ｂからの作動油を前記高速昇降用経路４２の正回転側に供給する状態とし、昇降用油圧モータ２０を正回転方向に回転させて回転駆動装置１８をリーダ１６に沿って下降させる。このときも、高速回転用油圧ポンプ３２ｂから昇降用油圧モータ２０へ作動油を大流量で供給することになるので、回転駆動装置１８の下降速度を大幅に向上させることができる。 As shown in FIG. 2B, when the rotation driving device 18 is raised to the upper end of the reader 16, the rotation control control valves 36a and 36b and the elevation control control valve 37 are stopped and the work rod 21 is rotated and rotated. The raising of the driving device 18 is stopped to temporarily suspend the work, and the holding of the work rod 21 is switched from the upper chuck 23 to the lower chuck 24, and the lifting speed switching control valve 43 is operated to operate from the high-speed rotation hydraulic pump 32b. In this state, the hydraulic oil 20 for raising and lowering is rotated in the forward rotation direction, and the rotary drive device 18 is lowered along the reader 16. Also at this time, since the hydraulic fluid is supplied from the high-speed rotation hydraulic pump 32b to the lifting hydraulic motor 20 at a large flow rate, the lowering speed of the rotary drive device 18 can be greatly improved.

図２（ａ）に示すように、回転駆動装置１８がリーダ１６の下端に達したら、作業ロッド２１の保持を下部チャック２４から上部チャック２３に切り替えて回転駆動装置１８で作業ロッド２１の中間部を保持するようにした後、回転制御用コントロール弁３６ａ，３６ｂを操作して両回転用油圧ポンプ３２ａ，３２ｂから回転用油圧モータ２２に作動油を供給して作業ロッド２１を所定の回転数で回転させながら、昇降制御用コントロール弁３７を逆方向に操作して昇降用油圧ポンプ３３から昇降用油圧モータ２０の逆回転方向に作動油を供給し、昇降用油圧モータ２０を逆回転させて回転駆動装置１８を所定の上昇速度でリーダ１６に沿って最上部まで上昇させる。これにより、一つの作業場所の地盤改良作業が終了する。 As shown in FIG. 2A, when the rotation driving device 18 reaches the lower end of the reader 16, the holding of the work rod 21 is switched from the lower chuck 24 to the upper chuck 23, and the rotation driving device 18 uses the intermediate portion of the work rod 21. Then, the rotation control valves 36a and 36b are operated to supply hydraulic oil to the rotation hydraulic motor 22 from the both rotation hydraulic pumps 32a and 32b, and the work rod 21 is rotated at a predetermined rotation speed. While rotating, the lift control valve 37 is operated in the reverse direction to supply hydraulic oil from the lift hydraulic pump 33 in the reverse rotation direction of the lift hydraulic motor 20, and the lift hydraulic motor 20 is rotated in reverse. The drive device 18 is raised to the top along the reader 16 at a predetermined rising speed. Thereby, the ground improvement work of one work place is completed.

このように、作業を一時中断して回転駆動装置１８による作業ロッド２１の保持位置を中間部から上部に、あるいは、上部から中間部に変更する際に、昇降用油圧モータ２０への作動油の供給を、昇降用油圧ポンプ３３から大容量の高速回転用油圧ポンプ３２ｂへとに切り替えることにより、作業ロッド２１の保持を解除した回転駆動装置１８を高速で昇降させることができるので、作業の一時中断時間を短縮することができ、一つの作業現場で多数の地盤改良を行う際の全体の作業時間を大幅に短縮して作業効率を大幅に向上させることができる。 Thus, when the operation is temporarily interrupted and the holding position of the work rod 21 by the rotation drive device 18 is changed from the middle part to the upper part or from the upper part to the middle part, the hydraulic oil to the lifting hydraulic motor 20 is changed. By switching the supply from the raising / lowering hydraulic pump 33 to the large-capacity high-speed rotating hydraulic pump 32b, the rotary drive device 18 released from the holding of the work rod 21 can be moved up and down at high speed. The interruption time can be shortened, and the overall work time when performing a large number of ground improvements at one work site can be greatly shortened, and work efficiency can be greatly improved.

また、前記昇降用油圧モータ２０に、過回転を防止する手段として、該昇降用油圧モータ２０の回転数を検出する回転数検出器を設けておき、該回転数検出器で検出した昇降用油圧モータ２０の回転数があらかじめ設定された回転数を超えたときに、ブザーやランプで警告を発生するように形成することにより、昇降用油圧モータ２０を過回転状態にすることがなくなり、昇降用油圧モータ２０の過回転に起因する様々な不都合、例えば、昇降用油圧モータ２０の焼き付き、昇降用チェーン１９の切断、リーダ１６と回転駆動装置１８との間に設けられた昇降ガイド部材の損傷などのトラブルの発生を未然に防止することができる。 The lifting hydraulic motor 20 is provided with a rotation speed detector for detecting the rotation speed of the lifting hydraulic motor 20 as means for preventing over-rotation, and the lifting hydraulic pressure detected by the rotation speed detector is provided. By forming a warning with a buzzer or a lamp when the rotational speed of the motor 20 exceeds a preset rotational speed, the lifting hydraulic motor 20 is not over-rotated, and the lifting Various inconveniences caused by excessive rotation of the hydraulic motor 20, for example, seizure of the lifting hydraulic motor 20, cutting of the lifting chain 19, damage to the lifting guide member provided between the reader 16 and the rotation driving device 18, etc. The occurrence of trouble can be prevented in advance.

なお、本形態例では、杭打機を使用して地盤改良作業を行う例を挙げたが、地中に鋼管杭を継ぎ足して埋設する鋼管杭の埋設作業にも適用することができ、地盤改良と鋼管埋設とを兼用した杭打機に限らず、地盤改良専用機や鋼管埋設専用機にも適用することができる。また、昇降用油圧モータ２０の過回転を防止する手段として、回転数検出器で検出した昇降用油圧モータ２０の回転数に応じてバイパス弁を開閉するなどの制御を行うことにより、昇降用油圧モータ２０の過回転を自動的に防止することも可能である。さらに、本形態例では、昇降速度切替用コントロール弁４３を回転制御用コントロール弁３６ｂの上流側に直列で配置しているが、回転用経路４１から高速昇降用経路４２を分岐させた後、回転用経路４１に回転制御用コントロール弁３６ｂを、分岐後の高速昇降用経路４２に昇降速度切替用コントロール弁４３をそれぞれ設けるようにすることもできる。また、回転制御用コントロール弁３６ｂの下流側の回転用経路４１に、昇降速度切替弁となる流路切替弁を設け、この流路切替弁によって作動油の流路を回転用経路４１と高速昇降用経路４２とに切り替えるようにすることもできる。 In this embodiment, the example of performing ground improvement work using a pile driving machine has been given, but it can also be applied to steel pipe pile burial work in which steel pipe piles are added and buried in the ground. It can be applied not only to a pile driving machine that combines the use of steel pipes and steel pipes, but also to ground improvement machines and steel pipes. Further, as means for preventing the over-rotation of the lifting hydraulic motor 20, by performing control such as opening and closing the bypass valve in accordance with the rotational speed of the lifting hydraulic motor 20 detected by the rotational speed detector, the lifting hydraulic pressure is controlled. It is also possible to automatically prevent the motor 20 from over-rotating. Further, in this embodiment, the control valve 43 for switching the ascending / descending speed is arranged in series on the upstream side of the control valve 36b for controlling the rotation. It is also possible to provide a control valve 36b for rotation control in the path 41 for use, and a control valve 43 for switching up / down speed in the high speed lift path 42 after branching. In addition, a flow path switching valve serving as an elevation speed switching valve is provided in the rotation path 41 downstream of the rotation control control valve 36b, and the flow path of the hydraulic oil is moved up and down with the rotation path 41 by this flow path switching valve. It is also possible to switch to the work path 42.

１１…杭打機、１２…下部走行体、１３…上部旋回体、１４…ベースマシン、１５…フロントブラケット、１６…リーダ、１７…起伏シリンダ、１８…回転駆動装置、１９…昇降用チェーン、２０…昇降用油圧モータ、２１…作業ロッド、２１ａ…中間角軸部、２１ｂ…上部角軸部、２１ｃ…中間チャック部、…、２１ｄ…上部チャック部、２１ｅ…掘削撹拌ヘッド、２２…回転用油圧モータ、２３…上部チャック、２４…下部チャック、２５…運転室、３１…エンジン、３２ａ…低速回転用油圧ポンプ、３２ｂ…高速回転用油圧ポンプ、３３…昇降用油圧ポンプ、３４…オイルクーラ用油圧ポンプ、３５…パイロット用油圧ポンプ、３６ａ，３６ｂ…回転制御用コントロール弁、３７…昇降制御用コントロール弁、３８…、３９…、４１…回転用経路、４２…高速昇降用経路、４３…昇降速度切替弁（昇降速度切替用コントロール弁）、４４…昇降用経路 DESCRIPTION OF SYMBOLS 11 ... Pile driver, 12 ... Lower traveling body, 13 ... Upper turning body, 14 ... Base machine, 15 ... Front bracket, 16 ... Leader, 17 ... Lifting cylinder, 18 ... Rotary drive, 19 ... Elevating chain, 20 DESCRIPTION OF SYMBOLS: Hydraulic motor for raising / lowering, 21 ... Working rod, 21a ... Intermediate angle shaft part, 21b ... Upper angle shaft part, 21c ... Intermediate chuck part, ..., 21d ... Upper chuck part, 21e ... Excavation stirring head, 22 ... Hydraulic pressure for rotation Motor, 23 ... Upper chuck, 24 ... Lower chuck, 25 ... Driver's cab, 31 ... Engine, 32a ... Hydraulic pump for low speed rotation, 32b ... Hydraulic pump for high speed rotation, 33 ... Hydraulic pump for lifting / lowering, 34 ... Hydraulic pressure for oil cooler Pump, 35 ... pilot hydraulic pump, 36a, 36b ... control valve for rotation control, 37 ... control valve for lift control, 38 ..., 39 ..., 41 ... Diversion route, 42 ... high speed lifting path, 43 ... lifting speed switching valve (lifting speed switching control valve), 44 ... lifting path

Claims

A rotary drive device provided so as to be able to move up and down along a reader standing on the base machine, a hydraulic motor for raising and lowering the rotary drive device along the reader, and hydraulic oil to the hydraulic motor for raising and lowering A pile driving machine comprising: an elevating hydraulic pump to be supplied; a rotary hydraulic motor for rotationally driving a work rod mounted on the rotary drive device; and a rotary hydraulic pump for supplying hydraulic oil to the rotary hydraulic motor In the machine, a hydraulic pump having a larger capacity than the lifting hydraulic pump is installed as the rotating hydraulic pump, and the hydraulic pump is discharged from the rotating hydraulic pump in the middle of a path for supplying hydraulic oil from the rotating hydraulic pump to the rotating hydraulic motor. A path for supplying the hydraulic oil to the lifting hydraulic motor is provided, and the lifting speed is cut off to supply the hydraulic oil discharged from the rotating hydraulic pump to the lifting hydraulic motor. Pile driver, characterized in that a valve.

The pile driving machine according to claim 1, wherein the lifting hydraulic motor includes means for preventing the lifting hydraulic motor from over-rotating.