JPH0976172A - Hydraulic driving mechanism - Google Patents
Hydraulic driving mechanismInfo
- Publication number
- JPH0976172A JPH0976172A JP23685295A JP23685295A JPH0976172A JP H0976172 A JPH0976172 A JP H0976172A JP 23685295 A JP23685295 A JP 23685295A JP 23685295 A JP23685295 A JP 23685295A JP H0976172 A JPH0976172 A JP H0976172A
- Authority
- JP
- Japan
- Prior art keywords
- valve
- port
- piston
- chamber
- stroke
- 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.)
- Granted
Links
Landscapes
- Percussive Tools And Related Accessories (AREA)
Abstract
Description
【０００１】[0001]
【発明の属する技術分野】この発明は、油圧ブレーカ等
に用いられる液圧式打撃機構に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydraulic hitting mechanism used for a hydraulic breaker or the like.
【０００２】[0002]
【従来の技術】従来、液圧式打撃機構として、図４に示
すように、中央に大径部１Ｂその前後に小径部１Ａ、１
Ｃを有するピストン１をシリンダ２内に摺嵌して前室３
と後室４とを形成し、前室３を高圧回路５へ連通させる
前室高圧ポート６と、制御弁７の前後進切換えにより後
室４を高圧回路５と低圧回路８とへそれぞれ連通させる
後室高圧ポート９と後室低圧ポート１０とを設け、制御
弁７の前後進切換えを行う弁制御室１１に弁制御回路１
２で接続される弁前進制御ポート１３を、ピストン１が
後進したとき前室３と連通する位置に設け、その後方に
所定距離離隔して弁制御室１１に弁制御回路１２で接続
される弁後進制御ポート１４と、低圧回路８に連通され
る排液ポート１５とを設け、ピストン１が前進したとき
弁後進制御ポート１４と排液ポート１５とを連通させる
排液溝１６をピストン１の大径部１Ｂの外周に設けたも
のが用いられている。2. Description of the Related Art Conventionally, as a hydraulic striking mechanism, as shown in FIG. 4, a large diameter portion 1B is provided at the center and a small diameter portion 1A is provided at the front and rear thereof.
The piston 1 having C is slidably fitted into the cylinder 2 so that the front chamber 3
And a rear chamber 4 are formed, and the front chamber high-pressure port 6 that connects the front chamber 3 to the high-voltage circuit 5 and the rear chamber 4 communicates with the high-voltage circuit 5 and the low-pressure circuit 8 by switching the control valve 7 between forward and backward. The rear chamber high pressure port 9 and the rear chamber low pressure port 10 are provided, and the valve control circuit 1 is provided in the valve control chamber 11 for switching the control valve 7 between forward and backward movement.
A valve forward control port 13 connected by 2 is provided at a position communicating with the front chamber 3 when the piston 1 moves backward, and a valve connected by a valve control circuit 12 to the valve control chamber 11 with a predetermined distance behind it. A reverse control port 14 and a drain port 15 communicating with the low-pressure circuit 8 are provided, and a drain groove 16 for communicating the valve reverse control port 14 with the drain port 15 when the piston 1 moves forward has a large drain groove 16 of the piston 1. What is provided on the outer periphery of the diameter portion 1B is used.
【０００３】図４の液圧式打撃機構では、シリンダ１に
バルブプラグ１７を嵌着して、バルブプラグ１７の外周
とシリンダ１の内周との間に、ピストン１と同心状の弁
室１８を形成し、この弁室１８に円筒状の制御弁７を摺
嵌している。弁室１８には、高圧回路５と連通して制御
弁７を後方に付勢する弁規制室１９が設けられ、弁室１
８の前端部及び後端部は常時低圧回路８と連通してい
る。In the hydraulic striking mechanism of FIG. 4, a valve plug 17 is fitted in the cylinder 1, and a valve chamber 18 concentric with the piston 1 is provided between the outer circumference of the valve plug 17 and the inner circumference of the cylinder 1. The control valve 7 having a cylindrical shape is slidably fitted in the valve chamber 18. The valve chamber 18 is provided with a valve regulation chamber 19 that communicates with the high pressure circuit 5 and biases the control valve 7 rearward.
The front end portion and the rear end portion of 8 are always in communication with the low voltage circuit 8.
【０００４】この液圧式打撃機構は、制御弁７が前方に
ある状態では、後室４が給液孔２０で後室高圧ポート９
と連通されているので、後室４と前室３とは共に高圧回
路５と連通する。ピストン１の後室４側の受圧面積は前
室３側の受圧面積より大となっているので、ピストン１
は前進する。この状態では、弁前進制御ポート１３が前
室３側に開かれており、弁後進制御ポート１４はピスト
ン１の大径部１Ｂで閉じられているので、弁制御回路１
２を介して前室３と連通している弁制御室１１は高圧に
なっている。従って、弁規制室１９と弁制御室１１とは
共に高圧であり、弁制御室１１側の受圧面積が弁規制室
１９側の受圧面積より大となっているので、制御弁７は
前方に保持されている。In this hydraulic striking mechanism, when the control valve 7 is in the front, the rear chamber 4 has the liquid supply hole 20 and the rear chamber high pressure port 9 is provided.
Since the rear chamber 4 and the front chamber 3 are in communication with each other, the high pressure circuit 5 is in communication therewith. Since the pressure receiving area on the rear chamber 4 side of the piston 1 is larger than the pressure receiving area on the front chamber 3 side, the piston 1
Moves forward. In this state, the valve advancing control port 13 is opened to the front chamber 3 side and the valve advancing control port 14 is closed by the large diameter portion 1B of the piston 1, so that the valve control circuit 1
The valve control chamber 11 communicating with the front chamber 3 via 2 has a high pressure. Therefore, both the valve control chamber 19 and the valve control chamber 11 are at a high pressure, and the pressure receiving area on the valve control chamber 11 side is larger than the pressure receiving area on the valve control chamber 19 side. Have been.
【０００５】ピストン１が前進すると、ピストン１の大
径部１Ｂで弁前進制御ポート１３が閉じられ、弁後進制
御ポート１４が排液溝１６を介して排液ポート１５と連
通するので、弁制御回路１２、弁制御室１１が低圧とな
る。このとき、弁規制室１９は高圧のままであるから、
制御弁７は後進する。制御弁７が後進すると給液孔２０
が閉じ排液孔２１が開いて、後室４が後室低圧ポート１
０を経て低圧回路８に連通する。前進したピストン１
は、ロッド２２の後端を打撃して前進を停止し、後室４
が低圧となっているため後進を開始する。When the piston 1 advances, the valve advance control port 13 is closed at the large diameter portion 1B of the piston 1, and the valve reverse control port 14 communicates with the drain port 15 through the drain groove 16, so that the valve control is performed. The circuit 12 and the valve control chamber 11 have a low pressure. At this time, the valve regulation chamber 19 remains at a high pressure,
The control valve 7 moves backward. When the control valve 7 moves backward, the liquid supply hole 20
Is closed, the drain hole 21 is opened, and the rear chamber 4 is connected to the rear chamber low-pressure port 1.
It communicates with the low voltage circuit 8 via 0. Piston 1 advanced
Hits the rear end of the rod 22 to stop the forward movement,
Starts reverse because of low pressure.
【０００６】ピストン１が後進すると、弁前進制御ポー
ト１３が前室３側に開かれ、弁後進制御ポート１４がピ
ストン１の大径部１Ｂで閉じられるので、弁制御回路１
２を介して前室３と連通した弁制御室１１は再び高圧と
なって制御弁７が前進する。制御弁７が前進すると、後
室４が後室高圧ポート９を経て高圧回路５と連通し、後
室４の圧力が上昇して、慣性により後進を続けようとす
るピストン１は制動を受け、後進の運動エネルギーが高
圧液の形でアキュムレータ（図示略）に蓄積される。後
進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 moves backward, the valve advancing control port 13 is opened to the front chamber 3 side, and the valve advancing control port 14 is closed by the large diameter portion 1B of the piston 1, so that the valve control circuit 1
The pressure in the valve control chamber 11, which communicates with the front chamber 3 through the pressure chamber 2, becomes high again, and the control valve 7 moves forward. When the control valve 7 moves forward, the rear chamber 4 communicates with the high-pressure circuit 5 through the rear chamber high-pressure port 9, the pressure in the rear chamber 4 increases, and the piston 1 that intends to continue reverse by inertia is subjected to braking. Reverse kinetic energy is stored in an accumulator (not shown) in the form of a high-pressure liquid. The piston 1 that has stopped moving backward enters the forward travel again, and the same cycle is repeated thereafter.
【０００７】また、この液圧式打撃機構には、掘さくす
る岩盤の岩質の変化や掘削工法の相違に対応して、打撃
力、打撃数を変更することができるように、弁前進制御
ポート１３の前方に所定距離離隔して弁制御回路１２と
接続される開閉可能なショートストロークポート２３を
設けたストローク可変式のものがある。ショートストロ
ークポート２３を開の状態にすると、ピストン１が後進
するとき、弁前進制御ポート１３が前室３側に開かれる
より早く、ショートストロークポート２３が前室３側に
開かれて、前室３と弁制御室１１とが弁制御回路１２を
介して連通し、制御弁７が前進してピストン１が前進行
程に入るタイミングが早くなるので、ピストン１のスト
ロークが短くなり、打撃数が増加して打撃力が小さくな
る。ショートストロークポート２３を閉の状態にする
と、ピストン１のストロークは正常なストロークに戻
り、打撃数が減少し打撃力が大きくなる。Further, the hydraulic striking mechanism has a valve advancing control port so that the striking force and the number of striking can be changed according to the change of the rock quality of the rock to be dug and the difference of the excavation method. There is a variable stroke type in which a short stroke port 23 which is openable and closable and which is connected to the valve control circuit 12 at a predetermined distance is provided in front of 13. When the short stroke port 23 is opened, when the piston 1 moves backward, the short stroke port 23 is opened to the front chamber 3 side earlier than the valve forward control port 13 is opened to the front chamber 3 side. 3 and the valve control chamber 11 communicate with each other via the valve control circuit 12, the control valve 7 moves forward, and the timing at which the piston 1 enters the forward stroke is advanced, so that the stroke of the piston 1 is shortened and the number of impacts is increased. And the striking power becomes smaller. When the short stroke port 23 is closed, the stroke of the piston 1 returns to a normal stroke, the number of impacts decreases, and the impact force increases.
【０００８】このような液圧式打撃機構は、ロッド２２
を破砕対象から離したときや、或いは破砕対象が破砕さ
れたときにピストン１がロッド２２を打撃しないで前後
進運動を継続する空打の状態となる。打撃力が大きいと
き空打が行われると、液圧式打撃機構それ自体ばかりで
なく、それを用いた油圧ブレーカ等を搭載する台車や油
圧回路を損傷し、耐久性が低下する。そこで、上記の液
圧式打撃機構に、ピストン１が打撃位置を越えて所定距
離前進したとき、後室４を排液ポート１５と連通させる
排液路と、前室高圧ポート６を排液溝１６を介して弁前
進制御ポート１３と連通させる連絡路とを設けることに
より、ロッド２２を破砕対象に押しつけると自動的に打
撃が開始され、ロッド２２を破砕対象から離したとき、
或いは破砕対象が破砕されたとき自動的に打撃が停止す
るようにした空打防止式のものも提案されている（特開
平４−３００１７２号参照）。連絡路を開閉可能とすれ
ば、空打可能状態と、空打防止状態とは選択切換でき
る。Such a hydraulic striking mechanism has a rod 22
Is separated from the crushing target, or when the crushing target is crushed, the piston 1 does not strike the rod 22 and the piston 2 continues to move forward and backward. If a hitting is performed when the hitting force is large, not only the hydraulic hitting mechanism itself but also a dolly or a hydraulic circuit equipped with a hydraulic breaker or the like using the hitting mechanism is damaged and durability is deteriorated. Therefore, when the piston 1 advances a predetermined distance beyond the striking position to the above hydraulic striking mechanism, a drainage passage for communicating the rear chamber 4 with the drainage port 15 and the front chamber high pressure port 6 for the drainage groove 16 are provided. By providing a communication path that communicates with the valve advancement control port 13 via, the impact is automatically started when the rod 22 is pressed against the crushing target, and when the rod 22 is separated from the crushing target,
Alternatively, there is also proposed a hitting prevention type in which the impact is automatically stopped when the object to be crushed is crushed (see Japanese Patent Laid-Open No. 4-300172). If the connecting path can be opened / closed, it is possible to selectively switch between the state in which the ball can be hit and the state in which the ball can be hit.
【０００９】[0009]
【発明が解決しようとする課題】一般に油圧ブレーカ等
を用いて作業を行う場合、液圧式打撃機構を長ストロー
ク即ち打撃力大とするときには空打防止が必要であり、
液圧式打撃機構を短ストローク即ち打撃力小とするとき
には空打可能状態とする。しかし、液圧式打撃機構をス
トローク可変とし、さらに空打防止を選択可能にする場
合には、ショートストロークポート２３の開閉を選択す
るための選択手段、及び前室高圧ポート６を弁前進制御
ポート１３と連通させる連絡路の開閉を選択するための
選択手段が必要となるため、構造が複雑となる。Generally, when working with a hydraulic breaker or the like, it is necessary to prevent idling when the hydraulic striking mechanism has a long stroke, that is, a large striking force.
When the hydraulic striking mechanism has a short stroke, that is, a striking force is small, it is in a state where it can be hit. However, when the stroke of the hydraulic striking mechanism is made variable and the prevention of idling can be selected, the selection means for selecting the opening / closing of the short stroke port 23 and the front chamber high pressure port 6 are set as the valve advance control port 13. Since the selection means for selecting the opening and closing of the communication path communicating with is necessary, the structure becomes complicated.
【００１０】また、これを操作する際には、オペレータ
は長ストローク・空打可能、長ストローク・空打防止、
短ストローク・空打可能、短ストローク・空打防止の４
通りの選択可能なモードの中から１つの作業モードを選
択しなければならず操作も面倒である。この発明は、オ
ペレータがストロークの長短の選択を行うだけで、長ス
トロークを選択したときには空打防止機能が働いて自動
スタート・自動停止が可能となり、短ストロークを選択
したときには空打可能となる液圧式打撃機構を提供する
ことを目的とする。When operating this, the operator can perform long stroke / idle stroke, long stroke / idle stroke prevention,
4 short strokes / driving possible, short strokes / driving prevention
One work mode has to be selected from among the selectable modes, and the operation is troublesome. In this invention, the operator simply selects the length of the stroke. When the long stroke is selected, the idling prevention function works to enable automatic start / stop, and when the short stroke is selected, the idling is possible. An object is to provide a pressure-type impact mechanism.
【００１１】[0011]
【課題を解決するための手段】この発明では、シリンダ
内に、中央に大径部その前後に小径部を有するピストン
を摺嵌して前室と後室とを形成し、前室を高圧回路へ連
通させる前室高圧ポートと、後室を制御弁へ連通させる
後室ポートとを設け、制御弁の前後進切換えによって前
記後室を低圧回路と高圧回路とに交互に切換え連通させ
てピストンを前後進させる液圧式打撃機構において、制
御弁の前後進切換えを行う弁制御室に弁制御回路で接続
される弁制御ポートを、ピストンが後進したとき前室と
連通する位置に設け、弁制御ポートの後方に低圧回路と
連通する排液ポートを設け、弁制御ポートの前方にショ
ートストロークポートを設け、ピストンが前進したとき
打撃位置の手前で弁制御ポートと排液ポートとを連通さ
せ、ピストンが打撃位置を越えて更に所定距離前進した
とき弁制御ポートとショートストロークポートとを連通
させる連通溝をピストンの大径部の外周に設け、前記シ
ョートストロークポートをストローク切換弁を介して、
弁制御回路と高圧回路とに切換え連通可能に接続するこ
とにより液圧式打撃機構の上記課題を解決している。According to the present invention, a front chamber and a rear chamber are formed by slidably fitting a piston having a large diameter portion in the center and a small diameter portion in the front and rear thereof in a cylinder, and the front chamber is a high voltage circuit. A high pressure port in the front chamber that communicates with the control chamber and a rear chamber port that communicates the rear chamber with the control valve are provided.By switching the control valve between forward and backward, the rear chamber is alternately switched between the low pressure circuit and the high pressure circuit to communicate with the piston. In a hydraulic striking mechanism that moves forward and backward, a valve control port that is connected by a valve control circuit to the valve control chamber that switches the control valve between forward and backward is provided at a position that communicates with the front chamber when the piston moves backward. A drain port that communicates with the low pressure circuit is provided in the rear of the valve, and a short stroke port is provided in front of the valve control port.When the piston advances, the valve control port and the drain port communicate with each other before the striking position. Hitting Provided communicating groove which communicates with the valve control port and a short-stroke port when the position was further predetermined distance forward beyond the outer periphery of the large diameter portion of the piston, the short stroke port via the stroke changeover valve,
The above problems of the hydraulic striking mechanism are solved by connecting the valve control circuit and the high pressure circuit so that they can be switched and communicated with each other.
【００１２】ショートストロークポートが高圧回路と連
通され、弁制御回路との連通が遮断されている状態で
は、液圧式打撃機構は長ストローク即ち打撃力大であ
り、ピストンが打撃位置を越えて所定距離前進すると
き、弁制御ポートが連通溝でショートストロークポート
と連通されて弁制御回路が高圧となり、制御弁を後進さ
せ後室を高圧としてピストン前進した状態で停止させる
ので、空打を防止できる。In the state where the short stroke port is in communication with the high pressure circuit and the communication with the valve control circuit is cut off, the hydraulic striking mechanism has a long stroke, that is, a large striking force, and the piston exceeds the striking position for a predetermined distance. When moving forward, the valve control port communicates with the short stroke port through the communication groove and the valve control circuit has a high pressure, and the control valve is moved backward and the rear chamber is stopped at a high pressure in the piston forward state, so idling can be prevented.
【００１３】ショートストロークポートが弁制御回路と
連通され、高圧回路との連通が遮断されている状態で
は、ピストンの後進時に前室と弁制御室とが弁制御回路
を介して連通し、制御弁を切換えてピストンが前進行程
に入るタイミングが早くなるので、液圧式打撃機構は短
ストローク即ち打撃力小となる。また、ピストンが打撃
位置を越えて所定距離前進しても弁制御回路は低圧のま
まであるから、ピストンはやがて後進に転じ前後進が継
続される。ストローク切換弁を切換える手動操作弁をオ
ペレータキャビン内に設けると、オペレータが液圧式打
撃機構の空打可能状態と空打防止状態の切換えのため、
液圧式打撃機構のところまで足を運ぶ必要がない。In a state where the short stroke port is in communication with the valve control circuit and the communication with the high pressure circuit is cut off, the front chamber and the valve control chamber communicate with each other through the valve control circuit when the piston moves backward and the control valve , The timing at which the piston enters the forward stroke is advanced, so that the hydraulic striking mechanism has a short stroke, that is, a small striking force. Also, even if the piston advances a predetermined distance beyond the striking position, the valve control circuit remains at a low pressure, so that the piston eventually turns backward and continues to move forward and backward. If a manually operated valve for switching the stroke switching valve is provided in the operator's cabin, the operator can switch between the idling possible state and the idling prevention state of the hydraulic striking mechanism.
There is no need to go to the hydraulic striking mechanism.
【００１４】[0014]
【発明の実施の形態】図１は本発明の実施の一形態を示
す液圧式打撃機構を用いた油圧ブレーカの縦断面図、図
２は液圧式打撃機構の回路図、図３はストローク切換弁
の配置状態を示すシリンダの断面図である。ここで、油
圧ブレーカＢのシリンダ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の上部に制御弁７
０とストローク切換弁３２とが設けられている。ピスト
ン１の前方にはロッド２２が挿着されている。1 is a longitudinal sectional view of a hydraulic breaker using a hydraulic striking mechanism according to an embodiment of the present invention, FIG. 2 is a circuit diagram of the hydraulic striking mechanism, and FIG. 3 is a stroke switching valve. FIG. 3 is a cross-sectional view of the cylinder showing the arrangement state of FIG. Here, the piston 1 is slidably fitted in the cylinder 2 of the hydraulic breaker B so as to be capable of reciprocating in the front-rear direction, and the control valve 7 is provided above the cylinder 2.
0 and the stroke switching valve 32 are provided. A rod 22 is inserted in front of the piston 1.
【００１５】ピストン１は、中央に大径部１Ｂ、その前
方に小径部１Ａ、後方に小径部１Ｃを有し、この径の相
違により前室３と後室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は後室４側の受圧面積が前室３側の受圧
面積より大である。シリンダ２には前室３を高圧回路５
へ連通させる前室高圧ポート２６と、後室４を制御弁７
０へ連通させる後室ポート２９とが設けられている。ま
た、ピストン１が後進したとき前室４と連通する位置に
弁制御ポート２４が設けられ、この弁制御ポート２４の
後方に低圧回路８と連通する排液ポート２５、弁制御ポ
ート２４の前方にショートストロークポート２７が設け
られている。The piston 1 has a large-diameter portion 1B in the center, a small-diameter portion 1A in the front thereof, and a small-diameter portion 1C in the rear thereof, and the difference in diameter forms a front chamber 3 and a rear chamber 4. The rear small-diameter portion 1C has a smaller diameter than the front small-diameter portion 1A, so that the piston 1 has a larger pressure receiving area on the rear chamber 4 side than on the front chamber 3 side. The cylinder 2 has a front chamber 3 and a high-voltage circuit 5
Front chamber high-pressure port 26 that communicates with the rear chamber 4 and control valve 7
A rear room port 29 for communicating with 0 is provided. Further, a valve control port 24 is provided at a position communicating with the front chamber 4 when the piston 1 moves backward, and a drain port 25 communicating with the low-pressure circuit 8 behind the valve control port 24 and a valve control port 24 in front of the valve control port 24. A short stroke port 27 is provided.
【００１６】ピストン１の大径部１Ｂの外周上には、ピ
ストン１が前進したとき打撃位置の手前で弁制御ポート
２４と排液ポート２５とを連通させ、ピストン１が打撃
位置を越えて更に所定距離前進したとき弁制御ポート２
４とショートストロークポート２７とを連通させる連通
溝３０が設けられている。制御弁７０は、バルブハウジ
ング７１内にバルブプラグ７２が嵌着され、その外周と
バルブハウジング７１の内周との間に、弁室７３を形成
している。この弁室７３内には円筒状の弁体７４が摺嵌
されており、弁室７３には、弁体７４の前後進切換えを
行う弁制御室７５と、高圧回路５と連通して弁体７４を
前方に付勢する弁規制室７６が設けられ、弁室７３の前
端部及び後端部は常時低圧回路８と連通している。ま
た、弁体７４には、後進時に後室４を高圧回路５と連通
させる給液孔７７と、前進時に後室４を低圧回路８と連
通させる排液孔７８とが設けられている。On the outer periphery of the large-diameter portion 1B of the piston 1, the valve control port 24 and the drainage port 25 are communicated with each other before the striking position when the piston 1 moves forward, and the piston 1 goes beyond the striking position and further. Valve control port 2 when moving forward a predetermined distance
4 is provided with a communication groove 30 that communicates with the short stroke port 27. In the control valve 70, a valve plug 72 is fitted in a valve housing 71, and a valve chamber 73 is formed between its outer circumference and the inner circumference of the valve housing 71. A cylindrical valve element 74 is slidably fitted in the valve chamber 73, and the valve chamber 73 is connected to the valve control chamber 75 for switching the valve element 74 between forward and backward and to communicate with the high pressure circuit 5. A valve regulation chamber 76 that biases 74 forward is provided, and the front end portion and the rear end portion of the valve chamber 73 are always in communication with the low pressure circuit 8. Further, the valve body 74 is provided with a liquid supply hole 77 for communicating the rear chamber 4 with the high pressure circuit 5 when moving backward, and a drain hole 78 for connecting the rear chamber 4 with the low pressure circuit 8 when moving forward.
【００１７】弁制御ポート２４は弁制御室７５に弁制御
回路３１で接続されている。また、ショートストローク
ポート２７は、ストローク切換弁３２を介して、弁制御
回路３１と高圧回路５とに切換え連通可能に接続されて
いる。ストローク切換弁３２はパイロット操作切換弁で
あり、そのパイロットポート３３は手動操作弁３４を介
して高圧回路５と低圧回路８とに連通される。The valve control port 24 is connected to the valve control chamber 75 by the valve control circuit 31. Further, the short stroke port 27 is connected to the valve control circuit 31 and the high pressure circuit 5 via the stroke switching valve 32 so as to be able to switch and communicate with each other. The stroke switching valve 32 is a pilot operation switching valve, and the pilot port 33 is connected to the high pressure circuit 5 and the low pressure circuit 8 via a manual operation valve 34.
【００１８】この液圧式打撃機構は、図２のようにショ
ートストロークポート２７と高圧回路５とを連通させて
いる場合、制御弁７０の弁体７４が後方にある状態で
は、後室４が給液孔７７を経て高圧回路５と連通されて
いるので、後室４と前室３とは共に高圧となっている。
ピストン１の後室４側の受圧面積は前室３側の受圧面積
より大となっているので、ピストン１は前進する。この
状態では、弁制御ポート２４が前室３側に開かれてお
り、排液ポート２５はピストン１の大径部１Ｂで閉じら
れているので、弁制御回路３１を介して前室３と連通し
ている弁制御室７５は高圧になっている。従って、弁規
制室７６と弁制御室７５とは共に高圧であり、弁制御室
７５側の受圧面積が弁規制室７６側の受圧面積より大で
あるから、切換弁７の弁体７４は後方に保持されてい
る。In this hydraulic striking mechanism, when the short stroke port 27 and the high pressure circuit 5 are communicated with each other as shown in FIG. 2, the rear chamber 4 is supplied with the valve body 74 of the control valve 70 at the rear side. Since it is communicated with the high-voltage circuit 5 through the liquid hole 77, both the rear chamber 4 and the front chamber 3 have high pressure.
Since the pressure receiving area on the rear chamber 4 side of the piston 1 is larger than the pressure receiving area on the front chamber 3 side, the piston 1 moves forward. In this state, the valve control port 24 is opened to the antechamber 3 side and the drain port 25 is closed at the large diameter portion 1B of the piston 1, so that the valve control circuit 31 communicates with the antechamber 3. The operating pressure of the valve control chamber 75 is high. Therefore, both the valve control chamber 76 and the valve control chamber 75 are at a high pressure, and the pressure receiving area on the valve control chamber 75 side is larger than the pressure receiving area on the valve control chamber 76 side. Is held in.
【００１９】ピストン１が前進すると、ピストン１の大
径部１Ｂで弁制御ポート２４が閉じられ、やがて打撃位
置の手前で弁制御ポート２４と排液ポート２５とが連通
溝３０で連通するので、弁制御回路３１、弁制御室７５
が低圧となる。このとき、弁規制室７６は高圧のままで
あるから、制御弁７の弁体７４は前進する。制御弁７０
の弁体７４が前進すると給液孔７７が閉じ排液孔７８が
開いて、後室４が低圧回路８に連通する。When the piston 1 advances, the valve control port 24 is closed at the large diameter portion 1B of the piston 1, and eventually the valve control port 24 and the drainage port 25 communicate with each other through the communication groove 30 before the striking position. Valve control circuit 31, valve control chamber 75
Becomes low pressure. At this time, the valve control chamber 76 remains at a high pressure, so the valve element 74 of the control valve 7 advances. Control valve 70
When the valve body 74 moves forward, the liquid supply hole 77 closes and the liquid discharge hole 78 opens, so that the rear chamber 4 communicates with the low pressure circuit 8.
【００２０】ここで、ロッド２２が図１に示すように所
定の打撃位置にあれば、ピストン１は、ロッド２２を打
撃して前進を停止し、後進を始める。ピストン１が後進
して前室３と弁制御ポート２４とが連通すると、弁制御
室７５が高圧となり、制御弁７０の弁体７４が後進す
る。ここで後室４が高圧回路５と連通して高圧となり、
慣性により後進を続けようとするピストン１は制動を受
け、後進の運動エネルギーが高圧液の形でアキュムレー
タ（図示略）に蓄積される。後進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。Here, if the rod 22 is at a predetermined striking position as shown in FIG. 1, the piston 1 strikes the rod 22 to stop the forward movement and start the backward movement. When the piston 1 moves backward and the front chamber 3 and the valve control port 24 communicate with each other, the valve control chamber 75 becomes high in pressure and the valve element 74 of the control valve 70 moves backward. Here, the rear chamber 4 communicates with the high voltage circuit 5 and becomes high pressure,
Due to the inertia, the piston 1 that tries to continue the backward movement is braked, and the kinetic energy of the backward movement is accumulated in the accumulator (not shown) in the form of high-pressure liquid. Piston 1 that stopped reverse
Goes into the previous step again, and the same cycle is repeated thereafter.
【００２１】ロッド２２を破砕対象から離したり、破砕
対象が破砕されてロッド２２が所定の打撃位置より前方
へ抜け出ているときには、ピストン１が前進して後室４
が低圧となった後も、ピストン１は慣性によってそのま
ま前進する。ピストン１が打撃位置を越えて所定距離前
進し、図２に示す位置に達すると、ショートストローク
ポート２７と弁制御ポート２４とが連通溝３０を介して
連通するため、弁制御室７５は高圧となって制御弁７０
の弁体７４が後進する。そこで、後室４は再度高圧回路
５と連通する。従って、ピストン１は後進に転ずること
なく前進し、後室４と排液ポート２５が連通し高圧回路
５と低圧回路８が連通してピストン１に高圧液が全く作
用しなくなり作動を停止し、空打が防止される。ロッド
２２を破砕対象に押しつけて、前方へ抜け出ている位置
から所定の打撃位置に戻せば、ピストン１はロッド２２
に押されて打撃位置に戻った後、通常の打撃状態に復帰
する。When the rod 22 is separated from the crushing target or when the crushing target is crushed and the rod 22 is slipping forward from a predetermined striking position, the piston 1 moves forward and the rear chamber 4
Even after the pressure becomes low, the piston 1 advances due to inertia. When the piston 1 advances a predetermined distance beyond the striking position and reaches the position shown in FIG. 2, the short stroke port 27 and the valve control port 24 communicate with each other through the communication groove 30, so that the valve control chamber 75 becomes high in pressure. Control valve 70
Of the valve element 74 moves backward. Therefore, the rear chamber 4 communicates with the high-pressure circuit 5 again. Therefore, the piston 1 moves forward without turning backward, the rear chamber 4 communicates with the drain port 25, the high pressure circuit 5 communicates with the low pressure circuit 8 and the high pressure liquid does not act on the piston 1 at all, and the operation is stopped. Runaway is prevented. If the rod 22 is pressed against the object to be crushed and returned to the predetermined striking position from the position where the rod 22 has been pulled forward, the piston 1
And returns to the striking position, and then returns to the normal striking state.
【００２２】ショートストロークポート２７と弁制御回
路３１とを連通させている場合、制御弁７０の弁体７４
が後方にある状態では、後室４が給液孔７７を経て高圧
回路５と連通されているので、後室４と前室３とは共に
高圧となっている。ピストン１の後室４側の受圧面積は
前室３側の受圧面積より大となっているので、ピストン
１は前進する。When the short stroke port 27 and the valve control circuit 31 are communicated with each other, the valve element 74 of the control valve 70 is used.
Is in the rear, the rear chamber 4 is in communication with the high-pressure circuit 5 through the liquid supply hole 77, so that both the rear chamber 4 and the front chamber 3 are at high pressure. Since the pressure receiving area on the rear chamber 4 side of the piston 1 is larger than the pressure receiving area on the front chamber 3 side, the piston 1 moves forward.
【００２３】ピストン１が前進すると、ピストン１の大
径部１Ｂで弁制御ポート２４とショートストロークポー
ト２７とが閉じられ、やがて打撃位置の手前で弁制御ポ
ート２４と排液ポート２５とが連通溝３０で連通するの
で、弁制御回路３１、弁制御室７５が低圧となる。この
とき、弁規制室７６は高圧のままであるから、制御弁７
の弁体７４は前進する。制御弁７０の弁体７４が前進す
ると給液孔７７が閉じ排液孔７８が開いて、後室４が低
圧回路８に連通する。When the piston 1 advances, the valve control port 24 and the short stroke port 27 are closed at the large diameter portion 1B of the piston 1, and eventually the valve control port 24 and the drain port 25 communicate with each other before the striking position. Since they communicate with each other, the valve control circuit 31 and the valve control chamber 75 have a low pressure. At this time, since the valve regulating chamber 76 remains at a high pressure, the control valve 7
Of the valve element 74 moves forward. When the valve element 74 of the control valve 70 moves forward, the liquid supply hole 77 closes and the liquid discharge hole 78 opens, and the rear chamber 4 communicates with the low pressure circuit 8.
【００２４】ここで、ロッド２２が図１に示すように所
定の打撃位置にあれば、ピストン１は、ロッド２２を打
撃して前進を停止し、後進を始める。ピストン１が後進
して前室３とショートストロークポート２７とが連通し
た段階で、弁制御室７５が高圧となり、制御弁７０の弁
体７４が後進する。ここで後室４が高圧回路５と連通し
て高圧となり、ピストン１は後進を停止して再び前進行
程にはいる。このように、前進行程に入るタイミングが
早くなるので、ピストン１のストロークが短くなる。Here, when the rod 22 is at a predetermined striking position as shown in FIG. 1, the piston 1 strikes the rod 22 to stop the forward movement and start the backward movement. When the piston 1 moves backward and the front chamber 3 and the short stroke port 27 communicate with each other, the pressure in the valve control chamber 75 becomes high, and the valve body 74 of the control valve 70 moves backward. Here, the rear chamber 4 communicates with the high-voltage circuit 5 to have a high pressure, and the piston 1 stops moving backward and enters the forward movement again. As described above, since the timing of entering the forward travel is earlier, the stroke of the piston 1 is shorter.
【００２５】ロッド２２が所定の打撃位置より前方へ抜
け出ているときには、ピストン１が前進して後室４が低
圧となった後も、ピストン１は慣性によってそのまま前
進するが、ピストン１が打撃位置を越えて前進しても、
弁制御室７５は低圧のままであり、制御弁７０の弁体７
４が前進位置に保持されるので、ピストン１は制動を受
けて後進に転じ空打が継続される。When the rod 22 is slipping forward from a predetermined striking position, the piston 1 advances as it is due to inertia even after the piston 1 moves forward and the rear chamber 4 becomes low in pressure, but the piston 1 moves to the striking position. Even if you move forward beyond
The valve control chamber 75 remains at a low pressure, and the valve body 7 of the control valve 70 is
Since No. 4 is held at the forward position, the piston 1 is braked and turns to the reverse direction to continue hitting.
【００２６】このように、オペレータは手動操作弁３４
の操作により、破砕対象物の性状や作業の内容に応じ
て、ストロークの長短の選択を行うことができる。スト
ローク切換弁３２の切換操作を行う手動操作弁３４は、
油圧ブレーカＢを搭載した台車のオペレータキャビンに
設けておけば、オペレータは、油圧ブレーカの空打可能
状態と空打防止状態の切換えのため、油圧ブレーカのと
ころまで足を運ぶ必要はない。As described above, the operator manually operates the valve 34.
With the operation of, the length of the stroke can be selected according to the property of the crushing target and the content of the work. The manually operated valve 34 for switching the stroke switching valve 32 is
If the operator is provided in the operator cabin of the trolley equipped with the hydraulic breaker B, the operator does not have to go to the hydraulic breaker in order to switch between the idling possible state and the idling prevention state of the hydraulic breaker.
【００２７】長ストロークを選択し打撃力を大にしたと
きには空打が防止されるので、油圧ブレーカＢや台車の
破損を防止して耐久性を向上させることができ、また、
ロッド２２を破砕対象に押しつけ、破砕対象から離すだ
けで自動スタート・自動停止が可能となるので、操作が
容易である。法面仕上げ等では、短ストロークを選択す
ることにより、打撃力を小さくし、空打状態で細かな作
業を行うことができる。When a long stroke is selected and the striking force is increased, idling is prevented, so damage to the hydraulic breaker B and the carriage can be prevented and durability can be improved.
Automatic start / stop can be performed simply by pressing the rod 22 against the crushing target and separating it from the crushing target, so that the operation is easy. For slope finishing, etc., by selecting a short stroke, the striking force can be reduced and fine work can be performed in the idle state.
【００２８】[0028]
【発明の効果】以上説明したように、本発明の液圧打撃
機構では、オペレータがストロークの長短の選択を行う
ことにより、長ストロークを選択し打撃力を大にしたと
きには空打を防止し、短ストロークを選択し打撃力を小
にしたときには空打を可能とすることができる。ストロ
ーク切換弁の切換操作を行う手動操作弁は、液圧式打撃
機構を搭載した台車のオペレータキャビンに設けておけ
ば、オペレータは液圧式打撃機構の空打可能状態と空打
防止状態の切換えのため液圧式打撃機構のところまで足
を運ぶ必要はない。As described above, in the hydraulic striking mechanism of the present invention, the operator selects a long stroke or a short stroke to prevent idling when a long stroke is selected and the striking force is increased. When a short stroke is selected and the striking force is reduced, it is possible to make a blank hit. If a manually operated valve for switching the stroke switching valve is installed in the operator cabin of a trolley equipped with a hydraulic striking mechanism, the operator can switch between the idle striking state and the idle striking prevention state of the hydraulic striking mechanism. There is no need to go to the hydraulic striking mechanism.
【図１】本発明の一形態を示す液圧式打撃機構を用いた
油圧ブレーカの縦断面図である。FIG. 1 is a vertical sectional view of a hydraulic breaker using a hydraulic striking mechanism according to an embodiment of the present invention.
【図２】液圧式打撃機構の回路図である。FIG. 2 is a circuit diagram of a hydraulic striking mechanism.
【図３】ストローク切換弁の配置状態を示すシリンダの
断面図である。FIG. 3 is a sectional view of a cylinder showing an arrangement state of a stroke switching valve.
【図４】従来の液圧式打撃機構の縦断面図である。FIG. 4 is a vertical cross-sectional view of a conventional hydraulic striking mechanism.
１ ピストン １Ａ、１Ｃ 小径部 １Ｂ 大径部 ２ シリンダ ３ 前室 ４ 後室 ５ 高圧回路 ８ 低圧回路 ２２ ロッド ２４ 弁制御ポート ２５ 排液ポート ２６ 前室高圧ポート ２７ ショートストロークポート ２９ 後室ポート ３０ 連通溝 ３１ 弁制御回路 ３２ ストローク切換弁 ３４ 手動操作弁 ７０ 制御弁 ７１ バルブハウジング ７４ 弁体 ７５ 弁制御室 ７６ 弁規制室 ７７ 給液孔 ７８ 排液孔 Ｂ 油圧ブレーカ 1 Piston 1A, 1C Small diameter part 1B Large diameter part 2 Cylinder 3 Front chamber 4 Rear chamber 5 High pressure circuit 8 Low pressure circuit 22 Rod 24 Valve control port 25 Drainage port 26 Front chamber high pressure port 27 Short stroke port 29 Rear chamber port 30 Communication Groove 31 Valve control circuit 32 Stroke switching valve 34 Manual operation valve 70 Control valve 71 Valve housing 74 Valve body 75 Valve control chamber 76 Valve regulation chamber 77 Liquid supply hole 78 Discharge hole B Hydraulic breaker
Claims (2)
小径部を有するピストンを摺嵌して前室と後室とを形成
し、前室を高圧回路へ連通させる前室高圧ポートと、後
室を制御弁へ連通させる後室ポートとを設け、制御弁の
前後進切換えによって前記後室を低圧回路と高圧回路と
に交互に切換え連通させてピストンを前後進させる液圧
式打撃機構であって、制御弁の前後進切換えを行う弁制
御室に弁制御回路で接続される弁制御ポートを、ピスト
ンが後進したとき前室と連通する位置に設け、弁制御ポ
ートの後方に低圧回路と連通する排液ポートを設け、弁
制御ポートの前方にショートストロークポートを設け、
ピストンが前進したとき打撃位置の手前で弁制御ポート
と排液ポートとを連通させピストンが打撃位置を越えて
更に所定距離前進したとき弁制御ポートとショートスト
ロークポートとを連通させる連通溝をピストンの大径部
の外周に設け、前記ショートストロークポートをストロ
ーク切換弁を介して弁制御回路と高圧回路とに切換え連
通可能に接続したことを特徴とする液圧式打撃機構。1. A front chamber high-pressure port for communicating a front chamber with a high-voltage circuit by slidably fitting a piston having a large-diameter portion in the center and a small-diameter portion in the front and rear thereof in a cylinder to form a front chamber and a rear chamber. , A rear chamber port that communicates the rear chamber with the control valve, and by a forward / reverse switching of the control valve, the rear chamber is alternately switched between the low pressure circuit and the high pressure circuit to communicate and the piston is moved forward and backward. Therefore, a valve control port that is connected to the valve control chamber for switching the control valve between forward and backward is connected to the front chamber when the piston moves backward, and a low pressure circuit is provided behind the valve control port. A communicating drain port is provided, and a short stroke port is provided in front of the valve control port.
When the piston moves forward, the valve control port and the drain port communicate with each other before the striking position, and when the piston goes beyond the striking position and further advances a predetermined distance, the communication groove that connects the valve control port with the short stroke port communicates with the piston. A hydraulic striking mechanism, which is provided on the outer circumference of a large-diameter portion and is connected so that the short stroke port can be switched and communicated with a valve control circuit and a high pressure circuit via a stroke switching valve.
をオペレータキャビン内に設けたことを特徴とする請求
項１記載の液圧式打撃機構。2. The hydraulic striking mechanism according to claim 1, wherein a manual operation valve for switching the stroke switching valve is provided in the operator cabin.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP23685295A JP3672978B2 (en) | 1995-09-14 | 1995-09-14 | Hydraulic striking mechanism |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP23685295A JP3672978B2 (en) | 1995-09-14 | 1995-09-14 | Hydraulic striking mechanism |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0976172A true JPH0976172A (en) | 1997-03-25 |
| JP3672978B2 JP3672978B2 (en) | 2005-07-20 |
Family
ID=17006761
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP23685295A Expired - Lifetime JP3672978B2 (en) | 1995-09-14 | 1995-09-14 | Hydraulic striking mechanism |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3672978B2 (en) |
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2003061912A1 (en) * | 2002-01-18 | 2003-07-31 | Konan Electric Company Limited | Hydraulically operated low noise hammer |
| US7357132B2 (en) | 2004-11-09 | 2008-04-15 | Arizona Public Service Company | Positioning system and method of orienting an object using same |
| ITBA20120055A1 (en) * | 2012-09-24 | 2014-03-25 | Tecna Group Srl | SHOCK EXTRACTOR WITH PISTON AND OPTIMIZED HYDRAULIC CIRCUIT |
| CN110005015A (en) * | 2019-05-07 | 2019-07-12 | 徐州徐工挖掘机械有限公司 | A kind of the quartering hammer control system and control method of double gear frequency modulation |
| CN110944801A (en) * | 2017-07-24 | 2020-03-31 | 古河凿岩机械有限公司 | Hydraulic impact device |
| WO2022146353A1 (en) * | 2020-12-31 | 2022-07-07 | Inan Makina Sanayi Ve Ticaret Anonim Sirketi | Hydraulic rock breaker with anti-blank firing system |
| RU2812797C1 (en) * | 2020-12-31 | 2024-02-02 | Инан Макина Санайи Ве Тиджарет Аноним Ширкети | Hydraulic hammer with idle impact protection system |
-
1995
- 1995-09-14 JP JP23685295A patent/JP3672978B2/en not_active Expired - Lifetime
Cited By (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2003061912A1 (en) * | 2002-01-18 | 2003-07-31 | Konan Electric Company Limited | Hydraulically operated low noise hammer |
| US7357132B2 (en) | 2004-11-09 | 2008-04-15 | Arizona Public Service Company | Positioning system and method of orienting an object using same |
| ITBA20120055A1 (en) * | 2012-09-24 | 2014-03-25 | Tecna Group Srl | SHOCK EXTRACTOR WITH PISTON AND OPTIMIZED HYDRAULIC CIRCUIT |
| CN110944801A (en) * | 2017-07-24 | 2020-03-31 | 古河凿岩机械有限公司 | Hydraulic impact device |
| JPWO2019022021A1 (en) * | 2017-07-24 | 2020-05-28 | 古河ロックドリル株式会社 | Hydraulic hammering device |
| EP3659752A4 (en) * | 2017-07-24 | 2020-07-29 | Furukawa Rock Drill Co., Ltd. | Hydraulic hammering device |
| US11590642B2 (en) | 2017-07-24 | 2023-02-28 | Furukawa Rock Drill Co., Ltd. | Hydraulic hammering device |
| CN110005015A (en) * | 2019-05-07 | 2019-07-12 | 徐州徐工挖掘机械有限公司 | A kind of the quartering hammer control system and control method of double gear frequency modulation |
| CN110005015B (en) * | 2019-05-07 | 2023-06-06 | 徐州徐工挖掘机械有限公司 | Breaking hammer control system and control method for double-gear frequency modulation |
| WO2022146353A1 (en) * | 2020-12-31 | 2022-07-07 | Inan Makina Sanayi Ve Ticaret Anonim Sirketi | Hydraulic rock breaker with anti-blank firing system |
| RU2812797C1 (en) * | 2020-12-31 | 2024-02-02 | Инан Макина Санайи Ве Тиджарет Аноним Ширкети | Hydraulic hammer with idle impact protection system |
Also Published As
| Publication number | Publication date |
|---|---|
| JP3672978B2 (en) | 2005-07-20 |
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