JPS5825126Y2 - Safety device for hydraulic control circuit of double-acting hydraulic cylinder - Google Patents
Safety device for hydraulic control circuit of double-acting hydraulic cylinderInfo
- Publication number
- JPS5825126Y2 JPS5825126Y2 JP10775077U JP10775077U JPS5825126Y2 JP S5825126 Y2 JPS5825126 Y2 JP S5825126Y2 JP 10775077 U JP10775077 U JP 10775077U JP 10775077 U JP10775077 U JP 10775077U JP S5825126 Y2 JPS5825126 Y2 JP S5825126Y2
- Authority
- JP
- Japan
- Prior art keywords
- double
- hydraulic cylinder
- acting hydraulic
- cylinder
- acting
- 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.)
- Expired
Links
Description
【考案の詳細な説明】
本考案は複動油圧シリンダの油圧制御回路の安全装置に
関するものである。[Detailed Description of the Invention] The present invention relates to a safety device for a hydraulic control circuit for a double-acting hydraulic cylinder.
伸長方向の負荷を受ける複動油圧シリンダは、クレーン
ブームの起伏シリンダ等に用いられるものであるが、こ
の種複動油圧シリンダは次の如く横取されている。A double-acting hydraulic cylinder that receives a load in the direction of extension is used as a hoisting cylinder for a crane boom, etc., and this kind of double-acting hydraulic cylinder has been used as follows.
すなわち第１図において両端をシリンダボトム壁２とシ
リンダヘッド壁３で閉塞したシリンダ４内へ、油密且つ
摺動自在１こピストン５を嵌挿し、このピストン５にそ
の基端を取り付けたピストンロッド６の先端を油密且つ
摺動自在にシリンダヘッド壁３を貫通して延出させてお
り、この複動油圧シリンダ１のボトム側油室７およびヘ
ッド側油室８へ作動油を給排することにより、複動油圧
シリンダ１を伸縮、駆動させるものである。In other words, in FIG. 1, an oil-tight and slidable piston 5 is inserted into a cylinder 4 whose both ends are closed by a cylinder bottom wall 2 and a cylinder head wall 3, and a piston rod whose base end is attached to this piston 5. 6 extends through the cylinder head wall 3 in an oil-tight and slidable manner, and supplies and discharges hydraulic oil to the bottom side oil chamber 7 and the head side oil chamber 8 of this double-acting hydraulic cylinder 1. By doing so, the double-acting hydraulic cylinder 1 is expanded and contracted and driven.
複動油圧シリンダ１の両油室７，８は四方内冠位置の方
向切換弁９１こより選択的（こ圧油源１０とオイルタン
ク１１に接続されるようになっている。Both oil chambers 7 and 8 of the double-acting hydraulic cylinder 1 are selectively connected to a pressure oil source 10 and an oil tank 11 through a directional control valve 91 located at a four-way inner crown position.
１２はボトム壁２に設けたブラケット、１３はピストン
ロッド６先端に設けたブラケットである。12 is a bracket provided on the bottom wall 2, and 13 is a bracket provided at the tip of the piston rod 6.
第１図は複動油圧シリンダ１をクレーンブームの起伏シ
リンダとして用いた例を示しでいるか、ここでは複動油
圧シリンダの前記ブラケット１２はクレーンの基台１４
へ枢着連結され、ブラケット１３はクレーンブーム１５
へ枢着連結されている。FIG. 1 shows an example in which a double-acting hydraulic cylinder 1 is used as a hoisting cylinder of a crane boom.
The bracket 13 is pivotally connected to the crane boom 15.
Pivotally connected to.
前記ブーム１５は、その基端を基台１４へ起伏自在に枢
着連結されており、ブーム１５先端で荷を吊り上げるよ
うに横取している。The boom 15 has its base end pivotally connected to the base 14 so as to be able to rise and fall freely, and the tip of the boom 15 intercepts the load so as to lift it up.
したがって複動油圧シリンダ１は、クレーンブーム１５
の自重およびクレーンブーム１５先端で吊り上げた荷に
より伸長方向の負荷を受けることになる。Therefore, the double-acting hydraulic cylinder 1 is connected to the crane boom 15
The crane will receive a load in the extension direction due to its own weight and the load lifted by the tip of the crane boom 15.
このような伸長方向の負荷を受ける複動油圧シリンダ１
をその負荷に順な方向へ伸長する場合には、方向切換弁
９を操作しでヘッド側油室８の油を回路１６、方向切換
弁９、回路１７を経てオイルタンク１１へ排出すると共
に、油圧源１０からこの圧油源１０の圧油を方向切換弁
９に供給する回路１８、方向切換弁９、回路２０を経て
ボトム側油室７へ圧油を供給して複動油圧シリンダを伸
長動するのであるが、複動油圧シリンダ１が最伸長に達
するとピストン５がヘッド壁３に衝合して伸長動が停止
すると共（こボトム側油室７の油圧が油圧源１０１こ設
けられ油圧回路の最高圧を規定するＩＪ ＩＪ−フ弁２
１の設定圧まで上昇する。Double-acting hydraulic cylinder 1 subjected to such a load in the extension direction
When extending in the direction corresponding to the load, operate the directional control valve 9 to discharge the oil in the head side oil chamber 8 through the circuit 16, the directional control valve 9, and the circuit 17 to the oil tank 11, A circuit 18 that supplies pressure oil from the pressure oil source 10 to the directional control valve 9, a directional control valve 9, and a circuit 20 to supply pressure oil to the bottom oil chamber 7 to extend the double-acting hydraulic cylinder. However, when the double-acting hydraulic cylinder 1 reaches its maximum extension, the piston 5 collides with the head wall 3 and the extension stops (this is because the oil pressure in the bottom side oil chamber 7 is supplied to the oil pressure source 101). IJ-F valve 2 that regulates the maximum pressure of the hydraulic circuit
The pressure increases to the set pressure of 1.
この状態において複動油圧シリンダ１のシリンダ４に作
用する引張り方向の力の最大値Ｆは、Ｆ−Ｗ＋Ｐｏ５１
・・・・・・・・・・・・・・・・・・・・・・・・・
・・・・・（１）ただし、Ｗ；複動油圧シリンダ１に作
用する伸長方向の負荷の最大値
ｐｏ １１リリーフ弁２１の設定圧
Ｓ、；ピストン５のボトム側油室７側の
受圧面積
となる。In this state, the maximum value F of the force in the tensile direction acting on the cylinder 4 of the double-acting hydraulic cylinder 1 is F-W+Po51
・・・・・・・・・・・・・・・・・・・・・・・・
...(1) However, W: Maximum value of the load in the extension direction acting on the double-acting hydraulic cylinder 1 po 11 Set pressure S of the relief valve 21; Pressure receiving area of the bottom side oil chamber 7 side of the piston 5 becomes.
リリーフ弁２１の設定圧Ｐ。は、それがピストン５のヘ
ッド側油室８側の受圧面積Ｓ２に作用して複動油圧シリ
ンダ１をこれに作用する伸長方向の負荷（最大値）Ｗに
抗して縮小させるに充分な圧力すなわち、
Ｐｏ５２〉Ｗ
（こ設定されている。Setting pressure P of the relief valve 21. is a pressure that is sufficient to act on the pressure receiving area S2 on the head side oil chamber 8 side of the piston 5 and to reduce the double acting hydraulic cylinder 1 against the load (maximum value) W in the extension direction acting on it. That is, Po52>W (This is set.
ピストン５のボトム側油室７の受圧面積Ｓ１はヘッド側
油室８の受圧面積Ｓ２よりも犬、すなわち、Ｓ、＞Ｓ２
であるからＰｏ５１〉Ｐｏ５２〉Ｗ
となり、前記（１）式より、
Ｆ＞２Ｗ
なる関係式が威り立つ。The pressure receiving area S1 of the bottom side oil chamber 7 of the piston 5 is smaller than the pressure receiving area S2 of the head side oil chamber 8, that is, S,>S2
Therefore, Po51>Po52>W, and from equation (1) above, the relational expression F>2W stands out.
すなわち、複動油圧シリンダ１のシリンダ４には引張り
方向１こ負荷Ｗの２倍以上の力が作用し、この力はシリ
ンダ４、シリンダ４とボトム壁２の固着部およびシリン
ダ４とヘッド壁３の固着部（こ作用する。That is, a force that is more than twice the load W in the tensile direction 1 acts on the cylinder 4 of the double-acting hydraulic cylinder 1, and this force acts on the cylinder 4, the fixed part between the cylinder 4 and the bottom wall 2, and the cylinder 4 and the head wall 3. The fixed part (this works).
したがって従前の複動油圧シリンダ１にあっては強度を
確保するためこれらの部分の重量が増大するという欠点
を有しでいた。Therefore, the conventional double-acting hydraulic cylinder 1 had the disadvantage that the weight of these parts increased in order to ensure strength.
本考案は、以上の点（こ鑑みてなしたものであって、方
向切換弁９を操作して複動油圧シリンダ１が最伸長に達
した場合に自動的（こ複動油圧シリンダ１のボトム側油
室７へ供給される圧油をアンロードするよう１こし、以
って複動油圧シリンダ１の最伸長時１こボトム側油室７
の油圧によって当該複動油圧シリンダ１の引張り方向に
生ずる力を低減させる新規な複動油圧シリンダの油圧制
御回路の安全装置を提供しようとするものである。The present invention was made in view of the above points, and when the double-acting hydraulic cylinder 1 reaches its maximum extension by operating the directional control valve 9, the bottom of the double-acting hydraulic cylinder 1 is automatically The pressure oil supplied to the side oil chamber 7 is strained once to unload it, so that when the double-acting hydraulic cylinder 1 is fully extended, the pressure oil supplied to the bottom side oil chamber 7 is
The present invention aims to provide a novel safety device for a hydraulic control circuit for a double-acting hydraulic cylinder that reduces the force generated in the pulling direction of the double-acting hydraulic cylinder 1 due to the hydraulic pressure of the cylinder.
以下本考案の複動油圧シリンダの油圧制御回路の安全装
置を、第１図に示した複動油圧シリンダの油圧制御回路
に実施した実施例につき第２図に基づいて説明する。The safety device for a hydraulic control circuit for a double-acting hydraulic cylinder according to the present invention will be described below with reference to FIG. 2 with reference to an embodiment implemented in the hydraulic control circuit for a double-acting hydraulic cylinder shown in FIG.
既述の説明において用いた付号は以下の説明においても
そのまま援用する。The numbers used in the above description will be used as they are in the following description.
第２図において、２２は複動油圧シリンダ１が伸長動し
てそのストロークエンドに近づくと作動して接となるリ
ミットスイッチで、複動油圧シリンダ１のシリンダヘッ
ド部（こ配設されその作動子２３をピストンロッド６先
端のブラケット１３に連動するストライカ−２４で作動
させるよう構成している。In FIG. 2, reference numeral 22 denotes a limit switch that is activated and closes when the double-acting hydraulic cylinder 1 extends and approaches its stroke end. 23 is operated by a striker 24 interlocked with the bracket 13 at the tip of the piston rod 6.
２５は、方向切換弁９を伸長方向に操作したときに作動
して接となるリミットスイッチで、このリミットスイッ
チ２５は、方向切換弁９の操作レバー２６（こ関連させ
て上述の如く作動するようにしでいる。Reference numeral 25 denotes a limit switch that is activated and turned on when the directional control valve 9 is operated in the extension direction. I'm in the middle of the day.
２７は、油圧源１０の圧油を方向切換弁９に供給する回
路１８とオイルタンク１１間に設けたソレノイド操作式
のアンロード弁でこのアンロード弁２７はその゛ルーノ
イド２８へ通電されると回路１８の圧油をオイルタンク
１１ヘアンロードし、通電が断たれると回路１８とオイ
ルタンク１１間の接続を断つように構威しでいる。Reference numeral 27 denotes a solenoid-operated unload valve installed between the oil tank 11 and the circuit 18 that supplies pressure oil from the hydraulic power source 10 to the directional control valve 9. The pressure oil in the circuit 18 is unloaded to the oil tank 11, and the connection between the circuit 18 and the oil tank 11 is cut off when the current is cut off.
そして、アンロード弁２７の操作用電気回路２９中には
、前記リミットスイッチ２２およびリミットスイッチ２
５を直列に組み込んでいる。The electric circuit 29 for operating the unload valve 27 includes the limit switch 22 and the limit switch 2.
5 are installed in series.
次に作用を説明する。Next, the action will be explained.
方向切換弁９を伸長方向へ操作して複動油圧シリンダ１
を伸長動させる場合、リミットスイッチ２５が作動して
接となっているので、複動油圧シリンダ１が伸長動して
ストロークエンドに近づくとリミットスイッチ２２が作
動して接となり、アンロード弁２７がアンロード作用を
する。Double-acting hydraulic cylinder 1 is activated by operating directional control valve 9 in the extension direction.
When extending, the limit switch 25 is activated and is in contact, so when the double-acting hydraulic cylinder 1 is extended and approaches the stroke end, the limit switch 22 is activated and in contact, and the unload valve 27 is in contact. Has an unloading effect.
方向切換弁９を縮小方向へ操作して複動油圧シリンダ１
を縮小動させる場合は、リミットスイッチ２５が断とな
っているので、アンロード弁２７はアンロード機能する
ことがない。Double-acting hydraulic cylinder 1 is activated by operating directional control valve 9 in the contraction direction.
When retracting, the limit switch 25 is turned off, so the unloading valve 27 does not perform the unloading function.
以上の如く本考案の複動油圧シリンダの油圧制御回路の
安全装置は、伸長方向の負荷を受ける複動油圧シリンダ
１のボトム側油室７およびヘッド側油室８を、四方向星
位置の方向切換弁９により選択的に圧油源１０とオイル
タンク１１に接続することにより複動油圧シリンダ１を
負荷（こ順な方向へ伸長並びに負荷に抗して縮小する油
圧制御回路において、複動油圧シリンダ１が伸長動して
ストロークエンドに近づくと作動するリミットスイッチ
２２、前記方向切換弁９を伸長方向ｆこ操作したときに
作動するリミットスイッチ２５、および油圧源１０の圧
油を方向切換弁９に供給する回路１８に設けられ当該回
路１８の圧油をアンロードするためのソレノイド操作式
のアンロード弁２７を設けると共に、前記両リミットス
イッチ２２゜２５が作動したときアンロード弁２７がア
ンロード作用するようアンロード弁２７の操作用電気回
路中に前記両リミットスイッチ２２．２５を組み込んだ
ものであるから、方向切換弁９を伸長方向（こ操作して
複動油圧シリンダ１が最伸長してストロークエンドに達
した場合に自動的にアンロード弁２７か働き、複動油圧
シリンダ１のボトム側油室７に供給される油圧をアンロ
ードして複動油圧シリンダ１のボトム側油室７の油圧の
上昇を押えることができ、シリンダ４、シリンダ４とボ
トム壁２の連結部、およびシリンダ４とヘッド壁３の連
結部に過大な力が作用することがなく、それだけ複動油
圧シリンダの軽量化とコストダウンがはかれることにな
り、その実用上の効果極めて犬である。As described above, the safety device of the hydraulic control circuit of the double-acting hydraulic cylinder of the present invention is designed to move the bottom side oil chamber 7 and head side oil chamber 8 of the double-acting hydraulic cylinder 1, which receives the load in the extension direction, in the four-direction star position. By selectively connecting the pressure oil source 10 and the oil tank 11 with the switching valve 9, the double-acting hydraulic cylinder 1 is loaded with a load (in a hydraulic control circuit that expands in the same direction and contracts against the load), the double-acting hydraulic cylinder 1 is A limit switch 22 that operates when the cylinder 1 extends and approaches the stroke end, a limit switch 25 that operates when the direction switching valve 9 is operated in the extension direction, and a limit switch 25 that operates when the cylinder 1 is extended and approaches the stroke end; A solenoid-operated unload valve 27 is provided in the circuit 18 for unloading the pressure oil in the circuit 18, and the unload valve 27 unloads when the limit switches 22 and 25 are activated. Since both limit switches 22 and 25 are incorporated into the electric circuit for operating the unload valve 27, the directional control valve 9 is operated in the extension direction (the double-acting hydraulic cylinder 1 is fully extended). When the stroke end is reached, the unload valve 27 automatically operates and unloads the hydraulic pressure supplied to the bottom side oil chamber 7 of the double acting hydraulic cylinder 1. This prevents excessive force from acting on the cylinder 4, the connection between the cylinder 4 and the bottom wall 2, and the connection between the cylinder 4 and the head wall 3. This will reduce weight and cost, and its practical effects will be extremely significant.
第１図は、伸長方向の負荷を受ける複動油圧シリンダの
油圧制御回路の説明図、第２図は第１図の油圧制御回路
へ実施した本考案の一実施例を示す。
１；複動油圧シリンダ、９；方向切換弁、１０；油圧源
、１１；オイルタンク、２２；リミットスイッチ、２５
；リミットスイッチ、２７；アンロード弁。FIG. 1 is an explanatory diagram of a hydraulic control circuit for a double-acting hydraulic cylinder that receives a load in the direction of extension, and FIG. 2 shows an embodiment of the present invention implemented in the hydraulic control circuit of FIG. 1; Double-acting hydraulic cylinder, 9; Directional switching valve, 10; Hydraulic pressure source, 11; Oil tank, 22; Limit switch, 25
;Limit switch, 27;Unload valve.
Claims (1)
油室７およびヘッド側油室８を、四方内冠位置の方向切
換弁９により選択的（こ圧油源１０とオイルタンク１１
に接続することにより複動油圧シリンダ１を負荷に順な
方向へ伸長並び１こ負荷に抗して縮小する油圧制御回路
において、複動油圧シリンダ１が伸長動してストローク
エンドに近づくと作動するリミットスイッチ２２、前記
方向切換弁９を伸長方向に操作したときに作動するリミ
ットスイッチ２５、および油圧源１０の圧油を方向切換
弁９に供給する回路１８に設けられ当該回路１８の圧油
をアンロードするためのソレノイド操作式のアンロード
弁２７を設けると共に、前記両リミットスイッチ２２．
２５が作動したときアンロード弁２７がアンロード作用
するようアンロード弁２７の操作用電気回路中ｌこ前記
両リミットスイッチ２２．２５を組み込んだことを特徴
とする複動油圧シリンダの油圧制御回路の安全装置。The bottom side oil chamber 7 and the head side oil chamber 8 of the double-acting hydraulic cylinder 1, which are subjected to loads in the extension direction, are selectively operated by a directional control valve 9 located at a four-way inner crown position (this pressure oil source 10 and oil tank 11
In a hydraulic control circuit that extends the double-acting hydraulic cylinder 1 in the direction of the load and contracts it against the load, the double-acting hydraulic cylinder 1 is activated when the double-acting hydraulic cylinder 1 extends and approaches the end of its stroke. A limit switch 22, a limit switch 25 that operates when the directional control valve 9 is operated in the extension direction, and a circuit 18 that supplies pressure oil from the hydraulic source 10 to the directional control valve 9, A solenoid-operated unload valve 27 for unloading is provided, and both limit switches 22.
A hydraulic control circuit for a double-acting hydraulic cylinder, characterized in that both limit switches 22 and 25 are incorporated in the electric circuit for operating the unload valve 27 so that the unload valve 27 performs an unloading operation when the unload valve 25 is activated. safety equipment.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP10775077U JPS5825126Y2 (en) | 1977-08-11 | 1977-08-11 | Safety device for hydraulic control circuit of double-acting hydraulic cylinder |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP10775077U JPS5825126Y2 (en) | 1977-08-11 | 1977-08-11 | Safety device for hydraulic control circuit of double-acting hydraulic cylinder |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS5434893U JPS5434893U (en) | 1979-03-07 |
| JPS5825126Y2 true JPS5825126Y2 (en) | 1983-05-30 |
Family
ID=29052156
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP10775077U Expired JPS5825126Y2 (en) | 1977-08-11 | 1977-08-11 | Safety device for hydraulic control circuit of double-acting hydraulic cylinder |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS5825126Y2 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2021131700A1 (en) * | 2019-12-27 | 2021-07-01 | 株式会社小松製作所 | Control system for work machine, work machine, control method for work machine, and control device for work machine |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5726055A (en) * | 1980-07-22 | 1982-02-12 | Nissan Motor Co Ltd | Cowl structure in automobile |
| JPS5812064U (en) * | 1981-07-17 | 1983-01-26 | 富士重工業株式会社 | Automobile front body structure |
| JPH0526324Y2 (en) * | 1985-02-15 | 1993-07-02 | ||
| JP3874444B2 (en) * | 1996-03-28 | 2007-01-31 | 株式会社タダノ | Automatic stop device for hydraulic work equipment |
-
1977
- 1977-08-11 JP JP10775077U patent/JPS5825126Y2/en not_active Expired
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2021131700A1 (en) * | 2019-12-27 | 2021-07-01 | 株式会社小松製作所 | Control system for work machine, work machine, control method for work machine, and control device for work machine |
| AU2020415637B2 (en) * | 2019-12-27 | 2023-12-21 | Komatsu Ltd. | Work machine control system, work machine, work machine control method, and work machine control device |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS5434893U (en) | 1979-03-07 |
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