JPH05337845A - Stroke mechanism for hydraulic rock drill - Google Patents

Stroke mechanism for hydraulic rock drill

Info

Publication number
JPH05337845A
JPH05337845A JP14761592A JP14761592A JPH05337845A JP H05337845 A JPH05337845 A JP H05337845A JP 14761592 A JP14761592 A JP 14761592A JP 14761592 A JP14761592 A JP 14761592A JP H05337845 A JPH05337845 A JP H05337845A
Authority
JP
Japan
Prior art keywords
piston
valve
chamber
oil
oil chamber
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
JP14761592A
Other languages
Japanese (ja)
Inventor
Yoshiichi Mikami
芳一 三上
Toshio Oi
敏夫 大井
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Furukawa Co Ltd
Original Assignee
Furukawa Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Furukawa Co Ltd filed Critical Furukawa Co Ltd
Priority to JP14761592A priority Critical patent/JPH05337845A/en
Publication of JPH05337845A publication Critical patent/JPH05337845A/en
Pending legal-status Critical Current

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Landscapes

  • Percussive Tools And Related Accessories (AREA)
  • Drilling And Exploitation, And Mining Machines And Methods (AREA)
  • Earth Drilling (AREA)

Abstract

PURPOSE:To regulate the rear end position of a piston stroke so as to suppress the occurrence of a failure by allowing a cushion chamber to be partitioned between the rear end face of a piston trying to continue its retreat by inertia and the valve plug of a rear oil chamber so as to confine pressure oil thereto. CONSTITUTION:A piston 1 having small diameter parts 1A, 1C at the front and rear parts and a large diameter part 1B at the intermediate part is fittingly mounted into a cylinder 2 to partition a front and a rear oil chambers. A valve chamber 7 is partitioned between the outer periphery of a valve plug 5 fittingly secured to the cylinder 2 and the inner periphery of the cylinder 2, and a cylindrical change-over valve 6 is accommodated in this valve chamber 7. The piston 1 is reciprocated to obtain stroke action by switching the oil pressure of the rear oil chamber to high/low pressure by the change-over valve 6. In this case, the rear inner diameter of the valve plug 5 is formed into the approximately same diameter as the large diameter part 1B of the piston 1, and the rear end part inner diameter of the valve plug 5 is formed into the approximately same diameter as the small diameter part 1C. A cushion chamber 27 to which pressure oil is confined by the retreat of the piston 1 can be partitioned so as to regulate the rear end position of a piston stroke by the confinement of pressure oil.

Description

【発明の詳細な説明】Detailed Description of the Invention

【0001】[0001]

【産業上の利用分野】本発明は、さく孔条件の変化によ
るピストンストロークの変動を規制し、打撃エネルギー
を安定させる油圧さく岩機の打撃機構に関する。
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a striking mechanism of a hydraulic rock drill that regulates fluctuations in piston stroke due to changes in drilling conditions and stabilizes striking energy.

【0002】[0002]

【従来の技術】従来、油圧さく岩機の打撃装置には、図
1に示すように、前後に小径部1A、1C、中間に大径
部1Bを有するピストン1をシリンダ2内に摺嵌して前
部油室3と後部油室4とを形成し、前記シリンダ2にバ
ルブプラグ5を嵌着して、バルブプラグ外周とシリンダ
内周との間に、円筒状の切換弁6をピストン1と同心状
に摺嵌する弁室7を形成し、該弁室7の前端部及び後端
部を常時低圧回路8と連通させ、高圧回路9と連通して
前記切換弁6を後方に付勢する弁規制油室10と、ピス
トン1の往復動によって開閉される制御ポート11に連
通して切換弁6を前方へ移動させる弁制御油室12とを
設け、切換弁6で前記後部油室4の油圧を高圧と低圧と
に切換えてピストン1を往復動させる打撃機構が用いら
れている(実公平2−24623号参照)。
2. Description of the Related Art Conventionally, as shown in FIG. 1, a striking device for a hydraulic rock drill has a piston 1 having small diameter portions 1A, 1C in the front and rear and a large diameter portion 1B in the middle slidably fitted in a cylinder 2. To form a front oil chamber 3 and a rear oil chamber 4, a valve plug 5 is fitted to the cylinder 2, and a cylindrical switching valve 6 is provided between the outer circumference of the valve plug and the inner circumference of the cylinder. A valve chamber 7 that is concentrically slidably fitted to the valve chamber 7, and the front end portion and the rear end portion of the valve chamber 7 are always communicated with the low pressure circuit 8 and the high pressure circuit 9 to urge the switching valve 6 rearward. And a valve control oil chamber 12 that communicates with the control port 11 that is opened and closed by the reciprocating movement of the piston 1 to move the switching valve 6 forward. A striking mechanism that reciprocates the piston 1 by switching the hydraulic pressure between high pressure and low pressure is used. See JP -24,623).

【0003】この打撃機構は、図1の下側に示すように
切換弁6が前方にある状態では、高圧ポート13と給排
油室14とが給油孔15を介して連通しているので、後
部油室4と前部油室3とは共に高圧回路9と連通する。
ピストン1の後部油室4側の受圧面積は前部油室3側の
受圧面積より大であるから、ピストン1は前進する。こ
の状態では、制御ポート11が前部油室3側に開かれて
おり、第2制御ポート16はピストン1の大径部1Bで
閉じられているので、弁制御通路17を介して前部油室
3と連通している弁制御油室12は高圧になっている。
従って、弁規制油室10と弁制御油室12とは共に高圧
であり、弁制御油室12側の受圧面積が弁規制油室10
側の受圧面積より大であるから、切換弁6は前方に保持
されている。
In this striking mechanism, the high pressure port 13 and the oil supply / exhaust chamber 14 communicate with each other through the oil supply hole 15 when the switching valve 6 is in the front as shown in the lower side of FIG. Both the rear oil chamber 4 and the front oil chamber 3 communicate with the high pressure circuit 9.
Since the pressure receiving area on the rear oil chamber 4 side of the piston 1 is larger than the pressure receiving area on the front oil chamber 3 side, the piston 1 moves forward. In this state, the control port 11 is opened to the front oil chamber 3 side, and the second control port 16 is closed at the large diameter portion 1B of the piston 1, so the front oil passage is controlled via the valve control passage 17. The valve control oil chamber 12 communicating with the chamber 3 has a high pressure.
Therefore, both the valve control oil chamber 10 and the valve control oil chamber 12 have a high pressure, and the pressure receiving area on the valve control oil chamber 12 side is the valve control oil chamber 10.
Since it is larger than the pressure receiving area on the side, the switching valve 6 is held forward.

【0004】ピストン1が前進すると、図1の上側に示
すようにピストン1の大径部1Bで制御ポート11が閉
じられ、第2制御ポート16が溝18を介して排油ポー
ト19と連通するので、弁制御通路17、弁制御油室1
2が低圧となる。このとき、弁規制油室10は高圧のま
まであるから、切換弁6は後退する。切換弁6が後退す
ると給油孔15が閉じ、排油孔20によって給排油室1
4が低圧ポート21と連通するので、後部油室4は低圧
回路8に連通する。前進したピストン1は、シャンクロ
ッド22の後端を打撃して前進を停止し、後部油室4が
低圧となっているため後退を開始する。
When the piston 1 advances, the control port 11 is closed at the large diameter portion 1B of the piston 1 as shown in the upper side of FIG. 1, and the second control port 16 communicates with the oil drain port 19 through the groove 18. Therefore, the valve control passage 17 and the valve control oil chamber 1
2 becomes low pressure. At this time, since the valve regulation oil chamber 10 is still at high pressure, the switching valve 6 moves backward. When the switching valve 6 moves backward, the oil supply hole 15 closes, and the oil discharge hole 20 allows the oil supply / discharge chamber 1 to be closed.
Since 4 communicates with the low pressure port 21, the rear oil chamber 4 communicates with the low pressure circuit 8. The advanced piston 1 strikes the rear end of the shank rod 22 to stop the advance, and starts the retreat because the rear oil chamber 4 has a low pressure.

【0005】ピストン1が後退すると、制御ポート11
が前部油室3側に開かれ、第2制御ポート16がピスト
ン1の大径部1Bで閉じられるので、弁制御通路17を
介して前部油室3と連通した弁制御油室12は再び高圧
となって切換弁6が前進する。切換弁6が前進すると、
給排油室14が高圧ポート13と連通し、後部油室4の
圧力が上昇して、慣性により後退を続けようとするピス
トン1は制動を受け、後退の運動エネルギーが高圧油の
形でアキュムレータ(図示略)に蓄積される。後退を停
止したピストン1は再び前進行程に入り、以後同様のサ
イクルが繰返される。
When the piston 1 retracts, the control port 11
Is opened to the front oil chamber 3 side and the second control port 16 is closed at the large diameter portion 1B of the piston 1, so that the valve control oil chamber 12 communicating with the front oil chamber 3 via the valve control passage 17 is The pressure becomes high again and the switching valve 6 advances. When the switching valve 6 moves forward,
The oil supply / exhaust chamber 14 communicates with the high pressure port 13, the pressure in the rear oil chamber 4 rises, and the piston 1 that tries to continue retreating due to inertia is braked, and the retreating kinetic energy is in the form of high pressure oil in the form of an accumulator. (Not shown). The piston 1 that has stopped retreating again enters the forward stroke, and the same cycle is repeated thereafter.

【0006】[0006]

【発明が解決しようとする課題】さく孔作業の際、さく
孔対象である岩石の状態は、さく孔の進行に伴って変化
する。特に、岩石の硬度が変化すると、シャンクロッド
の後端を打撃したときにピストンの受ける反力が変化
し、岩石の硬度が大になると後退するピストンの運動エ
ネルギーが大となるので、後退の停止が遅れストローク
が過大となる。ストロークが過大になると、ビット先端
のチップの欠損、脱落、ロッドの折損を生じやすく、ピ
ストン自体がシリンダ後部に衝突して欠損したり、スル
ーボルトの折損を生ずるおそれもある。また、ピストン
のストロークが変化すると打撃力が変動し、オペレータ
はさく岩機に適正な推力を与えるのが困難になりさく孔
能率が低下する。
During drilling work, the condition of the rock to be drilled changes as the drilling progresses. In particular, when the hardness of rock changes, the reaction force that the piston receives when hitting the rear end of the shank rod changes, and when the hardness of rock increases, the kinetic energy of the piston that retracts increases, so stopping the retraction However, the delay stroke becomes too large. If the stroke is too large, the tip of the bit is likely to be chipped, fallen off, or the rod is broken, and the piston itself may collide with the rear part of the cylinder and be broken, or the through bolt may be broken. Further, when the stroke of the piston changes, the striking force also fluctuates, making it difficult for the operator to give an appropriate thrust to the rock drill, and the drilling efficiency decreases.

【0007】本発明は、油圧さく岩機の打撃装置におけ
る上記問題を解決するものである。而して、本発明は、
ピストンストロークの後端位置を規制してストロークの
変化を少なくし、過大ストロークによるチップの欠損、
脱落、ロッドの折損、ピストンの欠損、スルーボルトの
折損等の故障を防止し、打撃力の変動を少なくしてさく
孔能率を向上させることのできる油圧さく岩機の打撃機
構を提供することを目的とする。
[0007] The present invention solves the above problems in the impact device of a hydraulic rock drill. Thus, the present invention is
Restricting the rear end position of the piston stroke to reduce stroke change, chipping due to excessive stroke,
To provide a striking mechanism of a hydraulic rock drill capable of preventing failure such as dropout, breakage of rod, loss of piston, breakage of through bolt, etc. and reducing fluctuation of striking force to improve drilling efficiency. To aim.

【0008】[0008]

【課題を解決するための手段】本発明は、前後に小径
部、中間に大径部を有するピストンをシリンダ内に摺嵌
して前部油室と後部油室とを形成し、前記シリンダにバ
ルブプラグを嵌着して、バルブプラグ外周とシリンダ内
周との間に、円筒状の切換弁をピストンと同心状に摺嵌
する弁室を形成し、該弁室の前端部及び後端部を常時低
圧回路と連通させ、前記切換弁を後方に付勢する弁規制
油室と、ピストンの往復動によって開閉される制御ポー
トに連通して切換弁を前方へ移動させる弁制御油室とを
設け、切換弁で前記後部油室の油圧を高圧と低圧とに切
換えてピストンを往復動させる油圧さく岩機の打撃装置
において、前記後部油室のバルププラグとピストンの大
径部後端面との間にピストンの後退により圧油が閉込め
られるクッション室を設け、このクッション室と高圧回
路との間に圧油流入通路を設けることにより上記課題を
解決している。
According to the present invention, a piston having a small diameter portion at the front and the rear and a large diameter portion at the middle is slidably fitted in a cylinder to form a front oil chamber and a rear oil chamber, and A valve plug is fitted, and a valve chamber is formed between the outer periphery of the valve plug and the inner periphery of the cylinder for slidingly fitting a cylindrical switching valve concentrically with the piston. The valve chamber has a front end portion and a rear end portion. A valve-regulating oil chamber that constantly communicates with the low-pressure circuit and biases the switching valve backward, and a valve control oil chamber that communicates with the control port that is opened and closed by the reciprocating movement of the piston to move the switching valve forward. In a striking device of a hydraulic rock drill that is provided with a switching valve to switch the hydraulic pressure of the rear oil chamber between high pressure and low pressure to reciprocate the piston, in a blast valve of the rear oil chamber and a rear end surface of the large diameter portion of the piston. Cushion chamber where pressure oil is confined by retreating piston Provided solves the above problems by providing a pressure oil inlet passage between the cushion chamber and the high pressure circuit.

【0009】[0009]

【作用】ピストンが後退すると、弁制御通路を介して前
部油室と連通した弁制御油室が高圧となって切換弁が前
進する。切換弁が前進すると、後部油室の圧力が上昇し
て、慣性により後退を続けようとするピストンは制動を
受ける。更にピストンが後退すると、後部油室のバルプ
プラグとピストンの大径部後端面との間にクッション室
が形成され、圧油が閉込められるので、後退の運動エネ
ルギーが大きな場合でも、ピストンストロークの後端位
置が規制され、ストロークが過大となることなくピスト
ンは前進行程に入る。ピストンが前進行程に入るとき、
クッション室には圧油流入通路から圧油が供給される。
When the piston moves backward, the pressure in the valve control oil chamber communicating with the front oil chamber via the valve control passage becomes high and the switching valve moves forward. When the switching valve moves forward, the pressure in the rear oil chamber rises, and the piston that tries to continue moving backward due to inertia is braked. When the piston further retracts, a cushion chamber is formed between the valve plug of the rear oil chamber and the rear end surface of the large-diameter portion of the piston to confine the pressure oil. The end position is regulated, and the piston enters the forward stroke without excessive stroke. When the piston moves forward,
Pressure oil is supplied to the cushion chamber from the pressure oil inflow passage.

【0010】[0010]

【実施例】この発明の油圧さく岩機の打撃機構の基本的
構成は、図1に示す従来の打撃機構と同様であり、シリ
ンダ2内にはピストン1が前後方向へ往復動可能に摺嵌
され、シリンダ2の後部にバルブプラグ5が嵌着されて
いる。ピストン1は、大径部1B、前方の小径部1A、
後方の小径部1Cを有し、この径の相違により前部油室
3と後部油室4とを形成している。後方の小径部1C
は、前方の小径部1Aより更に径が小さく、従って、ピ
ストン1は後部油室4側の受圧面積が前部油室3側の受
圧面積より大である。前部油室3は、高圧回路9によっ
て油圧源(図示略)に接続されている。
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The basic structure of the striking mechanism of a hydraulic rock drilling machine of the present invention is the same as that of the conventional striking mechanism shown in FIG. 1, and a piston 1 is slidably fitted in a cylinder 2 so that the piston 1 can reciprocate back and forth. The valve plug 5 is fitted to the rear portion of the cylinder 2. The piston 1 has a large diameter portion 1B, a front small diameter portion 1A,
It has a rear small-diameter portion 1C, and the difference in the diameter forms a front oil chamber 3 and a rear oil chamber 4. Rear small diameter section 1C
Has a smaller diameter than the front small-diameter portion 1A, and therefore the piston 1 has a larger pressure receiving area on the rear oil chamber 4 side than on the front oil chamber 3 side. The front oil chamber 3 is connected to a hydraulic pressure source (not shown) by a high pressure circuit 9.

【0011】シリンダ2の後部に嵌着れているバルブプ
ラグ5は、前方の外径を小さくして、その外周とシリン
ダ2の内周との間に、円筒状の切換弁6をピストン1と
同心状に摺嵌する弁室7を形成している。図2は弁室7
付近の拡大縦断面図である。弁室7には、後端部に低圧
ポート23、その前方に高圧ポート13、低圧ポート2
1、弁制御ポート25、前端部に低圧ポート24が順に
設けられており、高圧ポート13は高圧回路9によって
油圧源に接続され、低圧ポート21、23、24は低圧
回路8によってタンク(図示略)に接続され、弁制御ポ
ート25は弁制御通路17によりシリンダ2の前部に設
けられた制御ポート11、第2制御ポート16に接続さ
れている。弁室7の内側には、バルブプラグ5に穿設さ
れた給排油孔26を介して後部油室4と常時連通してい
る給排油室14が設けられている。
The valve plug 5 fitted in the rear portion of the cylinder 2 has a front outer diameter reduced, and a cylindrical switching valve 6 is concentric with the piston 1 between the outer circumference and the inner circumference of the cylinder 2. The valve chamber 7 is formed so as to be slidably fitted. 2 shows the valve chamber 7
It is an enlarged longitudinal cross-sectional view of the vicinity. The valve chamber 7 has a low pressure port 23 at the rear end, a high pressure port 13 and a low pressure port 2 in front of it.
1, a valve control port 25, and a low pressure port 24 at the front end are sequentially provided, the high pressure port 13 is connected to a hydraulic pressure source by a high pressure circuit 9, and the low pressure ports 21, 23 and 24 are connected by a low pressure circuit 8 to a tank (not shown). ), And the valve control port 25 is connected to the control port 11 and the second control port 16 provided in the front portion of the cylinder 2 by the valve control passage 17. Inside the valve chamber 7, there is provided an oil supply / discharge chamber 14 which is in constant communication with the rear oil chamber 4 through an oil supply / discharge hole 26 formed in the valve plug 5.

【0012】バルブプラグ5の給排油孔26後方の内径
は、ピストン1の大径部1Bと略等径とし、バルブプラ
グ5の後端部の内径はピストン1の小径部1Cと略等径
となっており、ピストン1の後退により圧油が閉込めら
れるクッション室28が形成される。このクッション室
28の後端と給排油孔26との間には、圧油流入路29
が設けられており、この圧油流入路29の途中には、チ
ェック弁30が設けられている。
The inner diameter of the valve plug 5 behind the oil supply / drain hole 26 is substantially equal to the large diameter portion 1B of the piston 1, and the inner diameter of the rear end portion of the valve plug 5 is substantially equal to the small diameter portion 1C of the piston 1. The cushion chamber 28 in which the pressure oil is confined is formed by the retreat of the piston 1. A pressure oil inflow path 29 is provided between the rear end of the cushion chamber 28 and the oil supply / discharge hole 26.
A check valve 30 is provided in the middle of the pressure oil inflow path 29.

【0013】切換弁6の外周は、後方が大径となるよう
段付とし、この段部で弁規制油室10が形成されてお
り、また、切換弁6の内周は、前方が小径となるよう段
付とし、この段部で弁制御油室12が形成されている。
弁制御油室12側の受圧面積は弁規制油室10側の受圧
面積より大である。切換弁6には、前進位置で高圧ポー
ト13を給排油室14へ連通させる給油孔15と、後退
位置で低圧ポート21を給排油室14へ連通させる排油
孔20が穿設されており、また、弁制御ポート25と弁
制御油室12とを連通させる弁制御孔27が穿設されて
いる。弁規制油室10は常時高圧ポート13と連通して
いる。
The outer periphery of the switching valve 6 is stepped so that the rear portion has a large diameter, and the valve regulating oil chamber 10 is formed at this step portion, and the inner periphery of the switching valve 6 has a small diameter portion at the front. The valve control oil chamber 12 is formed in this step portion.
The pressure receiving area on the valve control oil chamber 12 side is larger than the pressure receiving area on the valve regulating oil chamber 10 side. The switching valve 6 is provided with an oil supply hole 15 for communicating the high pressure port 13 with the oil supply / exhaust chamber 14 in the forward position and an oil discharge hole 20 for communicating the low pressure port 21 with the oil supply / exhaust chamber 14 in the retracted position. In addition, a valve control hole 27 that connects the valve control port 25 and the valve control oil chamber 12 is formed. The valve regulation oil chamber 10 is always in communication with the high pressure port 13.

【0014】シリンダ2には、前述のように制御ポート
11、第2制御ポート16が設けられ、その後方に低圧
回路8を介してタンクに接続される排油ポート19が設
けられている。制御ポート11、第2制御ポート16
は、ピストン1の前後進によって開閉されるピストン1
の大径部1Bには、ピストン1の前進位置で第2制御ポ
ート16と排油ポート19とを連通させる溝18が設け
られている。
As described above, the cylinder 2 is provided with the control port 11 and the second control port 16 and, behind it, the oil drain port 19 connected to the tank via the low pressure circuit 8. Control port 11, second control port 16
Is the piston 1 which is opened and closed by the forward and backward movement of the piston 1.
The large-diameter portion 1B is provided with a groove 18 that allows the second control port 16 and the oil drain port 19 to communicate with each other at the forward position of the piston 1.

【0015】この打撃機構は、図1の下側に示すように
切換弁6が前方にある状態では、高圧ポート13と給排
油室14とが給油孔15を介して連通しているので、後
部油室4と前部油室3とは共に高圧回路9と連通する。
ピストン1の後部油室4側の受圧面積は前部油室3側の
受圧面積より大であるから、ピストン1は前進する。こ
の状態では、制御ポート11が前部油室3側に開かれて
おり、第2制御ポート16はピストン1の大径部1Bで
閉じられているので、弁制御通路17を介して前部油室
3と連通している弁制御油室12は高圧になっている。
従って、弁規制油室10と弁制御油室12とは共に高圧
であり、弁制御油室12側の受圧面積が弁規制油室10
側の受圧面積より大であるから、切換弁6は前方に保持
されている。
In this striking mechanism, the high pressure port 13 and the oil supply / exhaust chamber 14 communicate with each other through the oil supply hole 15 when the switching valve 6 is in the front as shown in the lower side of FIG. Both the rear oil chamber 4 and the front oil chamber 3 communicate with the high pressure circuit 9.
Since the pressure receiving area on the rear oil chamber 4 side of the piston 1 is larger than the pressure receiving area on the front oil chamber 3 side, the piston 1 moves forward. In this state, the control port 11 is opened to the front oil chamber 3 side, and the second control port 16 is closed at the large diameter portion 1B of the piston 1, so the front oil passage is controlled via the valve control passage 17. The valve control oil chamber 12 communicating with the chamber 3 has a high pressure.
Therefore, both the valve control oil chamber 10 and the valve control oil chamber 12 have a high pressure, and the pressure receiving area on the valve control oil chamber 12 side is the valve control oil chamber 10.
Since it is larger than the pressure receiving area on the side, the switching valve 6 is held forward.

【0016】ピストン1が前進すると、図1の上側に示
すようにピストン1の大径部1Bで制御ポート11が閉
じられ、第2制御ポート16が溝18を介して排油ポー
ト19と連通するので、弁制御通路17、弁制御油室1
2が低圧となる。このとき、弁規制油室10は高圧のま
まであるから、切換弁6は後退する。切換弁6が後退す
ると給油孔15が閉じ、排油孔20によって給排油室1
4が低圧ポート21と連通するので、後部油室4は低圧
回路8に連通する。前進したピストン1は、シャンクロ
ッド22の後端を打撃して前進を停止し、後部油室4が
低圧となっているため後退を開始する。
When the piston 1 advances, the control port 11 is closed at the large diameter portion 1B of the piston 1 as shown in the upper side of FIG. 1, and the second control port 16 communicates with the oil drain port 19 through the groove 18. Therefore, the valve control passage 17 and the valve control oil chamber 1
2 becomes low pressure. At this time, since the valve regulation oil chamber 10 is still at high pressure, the switching valve 6 moves backward. When the switching valve 6 moves backward, the oil supply hole 15 closes, and the oil discharge hole 20 allows the oil supply / discharge chamber 1 to be closed.
Since 4 communicates with the low pressure port 21, the rear oil chamber 4 communicates with the low pressure circuit 8. The advanced piston 1 strikes the rear end of the shank rod 22 to stop the advance, and starts the retreat because the rear oil chamber 4 has a low pressure.

【0017】ピストン1が後退すると、制御ポート11
が前部油室3側に開かれ、第2制御ポート16がピスト
ン1の大径部1Bで閉じられるので、弁制御通路17を
介して前部油室3と連通した弁制御油室12は再び高圧
となって切換弁6が前進する。切換弁6が前進すると、
後部油室4の圧力が上昇して、慣性により後退を続けよ
うとするピストン1は制動を受ける。更にピストン1が
後退すると、後部油室4のバルププラグ5とピストン1
の大径部1B後端面との間にクッション室28が形成さ
れ、圧油が閉込められるので、後退の運動エネルギーが
大きな場合でも、ピストンストロークの後端位置が規制
され、ストロークが過大となることなくピストン1は前
進行程に入る。ピストン1が前進行程に入るとき、クッ
ション室28には圧油流入路29から圧油が供給され
る。ピストン1が給排油孔26を開くと、後部油室4に
は給排油孔26から直接圧油が流入する。以後同様のサ
イクルが繰返される。
When the piston 1 retracts, the control port 11
Is opened to the front oil chamber 3 side and the second control port 16 is closed at the large diameter portion 1B of the piston 1, so that the valve control oil chamber 12 communicating with the front oil chamber 3 via the valve control passage 17 is The pressure becomes high again and the switching valve 6 advances. When the switching valve 6 moves forward,
The pressure in the rear oil chamber 4 rises, and the piston 1 that tries to continue retreating due to inertia is braked. When the piston 1 further retracts, the valp plug 5 in the rear oil chamber 4 and the piston 1
Since the cushion chamber 28 is formed between the rear end face of the large-diameter portion 1B and the pressure oil is confined, the rear end position of the piston stroke is restricted and the stroke becomes excessive even when the kinetic energy of retreat is large. The piston 1 goes into the forward movement without moving. When the piston 1 enters the forward stroke, pressure oil is supplied to the cushion chamber 28 from the pressure oil inflow passage 29. When the piston 1 opens the oil supply / discharge hole 26, the pressure oil directly flows into the rear oil chamber 4 from the oil supply / discharge hole 26. After that, the same cycle is repeated.

【0018】この実施例では、更に、図3に示す様なス
トロークアジャスタ31が、図4に示すようにチェック
弁30と角度をずらして設けられている。このストロー
クアジャスタ31は、スリットの開度を調節してピスト
ン1の後退時にクッション室28から圧油を若干逃がす
ようにすることにより、ストロークの調整を行うことが
できる。
In this embodiment, a stroke adjuster 31 as shown in FIG. 3 is further provided at a different angle from the check valve 30 as shown in FIG. The stroke adjuster 31 can adjust the stroke by adjusting the opening of the slit so that the pressure oil is slightly released from the cushion chamber 28 when the piston 1 moves backward.

【0019】岩石の硬度が変化すると、シャンクロッド
22の後端を打撃したときにピストン1の受ける反力が
変化し、岩石の硬度が大になると後退するピストン1の
運動エネルギーが大となるが、ストロークが過大となる
ことなくピストン1は前進行程に入るので、ビット先端
のチップの欠損、脱落、ロッドの折損を生じたり、ピス
トン自体がシリンダ後部に衝突して欠損したり、スルー
ボルトの折損を生ずるおそれはない。また、ピストンの
ストロークが変化せず、打撃力が変動しないため、オペ
レータはさく岩機に適正な推力を与えることができさく
孔能率が向上する。
When the hardness of the rock changes, the reaction force received by the piston 1 when the rear end of the shank rod 22 is hit changes, and when the hardness of the rock increases, the kinetic energy of the piston 1 that retracts increases. Since the piston 1 goes into the forward stroke without excessive stroke, the tip of the bit may be chipped, dropped, the rod may be broken, or the piston itself may collide with the rear part of the cylinder and be broken, or the through bolt may be broken. There is no danger of Further, since the stroke of the piston does not change and the striking force does not change, the operator can apply an appropriate thrust to the rock drilling machine and the drilling efficiency improves.

【0020】[0020]

【発明の効果】以上説明したように、本発明の油圧さく
岩機の打撃機構は、ピストンストロークの後端位置を規
制してストロークの変化を少なくし、過大ストロークに
よるチップの欠損、脱落、ロッドの折損、ピストンの欠
損、スルーボルトの折損等の故障を防止できる。また、
打撃力の変動が少なくさく孔能率を向上させることがで
きる。
As described above, in the striking mechanism of the hydraulic rock drilling machine of the present invention, the rear end position of the piston stroke is regulated to reduce the change in stroke, and the tip is broken, dropped, or rods due to excessive stroke. It is possible to prevent breakage such as breakage of the piston, breakage of the piston and breakage of the through bolt. Also,
The fluctuation of the striking force is small and the hole efficiency can be improved.

【図面の簡単な説明】[Brief description of drawings]

【図1】従来の油圧さく岩機の打撃機構の縦断面図であ
る。
FIG. 1 is a longitudinal sectional view of a hitting mechanism of a conventional hydraulic rock drill.

【図2】本発明の油圧さく岩機の打撃機構の弁室付近の
拡大縦断面図である。
FIG. 2 is an enlarged vertical sectional view of the vicinity of the valve chamber of the striking mechanism of the hydraulic rock drill of the present invention.

【図3】本発明の油圧さく岩機の打撃機構の弁室付近の
拡大水平断面図である。
FIG. 3 is an enlarged horizontal sectional view of the vicinity of the valve chamber of the striking mechanism of the hydraulic rock drill of the present invention.

【図4】バルププラグの後端面図である。FIG. 4 is a rear end view of the valp plug.

【符号の説明】[Explanation of symbols]

1 ピストン 2 シリンダ 3 前部油室 4 後部油室 5 バルブプラグ 6 切換弁 7 弁室 8 低圧回路 9 高圧回路 10 弁規制油室 11 制御ポート 12 弁制御油室 28 クッション室 29 圧油流入路 30 チェック弁 1 Piston 2 Cylinder 3 Front Oil Chamber 4 Rear Oil Chamber 5 Valve Plug 6 Switching Valve 7 Valve Chamber 8 Low Pressure Circuit 9 High Pressure Circuit 10 Valve Restriction Oil Chamber 11 Control Port 12 Valve Control Oil Chamber 28 Cushion Chamber 29 Pressure Oil Inflow Channel 30 Check valve

Claims (1)

【特許請求の範囲】[Claims] 【請求項1】 前後に小径部、中間に大径部を有するピ
ストンをシリンダ内に摺嵌して前部油室と後部油室とを
形成し、前記シリンダにバルブプラグを嵌着して、バル
ブプラグ外周とシリンダ内周との間に、円筒状の切換弁
をピストンと同心状に摺嵌する弁室を形成し、該弁室の
前端部及び後端部を常時低圧回路と連通させ、前記切換
弁を後方に付勢する弁規制油室と、ピストンの往復動に
よって開閉される制御ポートに連通して切換弁を前方へ
移動させる弁制御油室とを設け、切換弁で前記後部油室
の油圧を高圧と低圧とに切換えてピストンを往復動させ
る油圧さく岩機の打撃装置において、前記後部油室のバ
ルププラグとピストンの大径部後端面との間にピストン
の後退により圧油が閉込められるクッション室を設け、
該クッション室と高圧回路との間に圧油流入路を設けた
ことを特徴とする油圧さく岩機の打撃機構。
1. A piston having front and rear small diameter parts and a middle large diameter part is slidably fitted into a cylinder to form a front oil chamber and a rear oil chamber, and a valve plug is fitted to the cylinder, Between the outer circumference of the valve plug and the inner circumference of the cylinder, a valve chamber in which a cylindrical switching valve is slidably fitted concentrically with the piston is formed, and a front end portion and a rear end portion of the valve chamber are constantly communicated with a low pressure circuit, A valve control oil chamber for urging the switching valve rearward and a valve control oil chamber for communicating the control port opened and closed by the reciprocating movement of the piston to move the switching valve forward are provided, and the rear oil is provided by the switching valve. In the impact device of a hydraulic rock drilling machine that reciprocates the piston by switching the hydraulic pressure of the chamber between high pressure and low pressure, pressure oil is generated by the retreat of the piston between the valve plug of the rear oil chamber and the rear end surface of the large diameter portion of the piston. There is a cushion room that can be closed,
A striking mechanism for a hydraulic rock drill, characterized in that a pressure oil inflow path is provided between the cushion chamber and the high pressure circuit.
JP14761592A 1992-06-08 1992-06-08 Stroke mechanism for hydraulic rock drill Pending JPH05337845A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP14761592A JPH05337845A (en) 1992-06-08 1992-06-08 Stroke mechanism for hydraulic rock drill

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP14761592A JPH05337845A (en) 1992-06-08 1992-06-08 Stroke mechanism for hydraulic rock drill

Publications (1)

Publication Number Publication Date
JPH05337845A true JPH05337845A (en) 1993-12-21

Family

ID=15434332

Family Applications (1)

Application Number Title Priority Date Filing Date
JP14761592A Pending JPH05337845A (en) 1992-06-08 1992-06-08 Stroke mechanism for hydraulic rock drill

Country Status (1)

Country Link
JP (1) JPH05337845A (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2012509199A (en) * 2008-11-20 2012-04-19 サンドビク マイニング アンド コンストラクション オサケ ユキチュア Jackhammer and axial bearing module
US8453756B2 (en) 2007-01-11 2013-06-04 Atlas Copco Rock Drills Ab Rock drilling equipment and a method in association with same
CN113124006A (en) * 2021-04-19 2021-07-16 中国铁建重工集团股份有限公司 Hydraulic system for continuously adjusting rock drilling power

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US8453756B2 (en) 2007-01-11 2013-06-04 Atlas Copco Rock Drills Ab Rock drilling equipment and a method in association with same
JP2012509199A (en) * 2008-11-20 2012-04-19 サンドビク マイニング アンド コンストラクション オサケ ユキチュア Jackhammer and axial bearing module
CN113124006A (en) * 2021-04-19 2021-07-16 中国铁建重工集团股份有限公司 Hydraulic system for continuously adjusting rock drilling power
CN113124006B (en) * 2021-04-19 2023-04-07 中国铁建重工集团股份有限公司 Hydraulic system for continuously adjusting rock drilling power

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