JPS6325138B2 - - Google Patents
Info
- Publication number
- JPS6325138B2 JPS6325138B2 JP1328481A JP1328481A JPS6325138B2 JP S6325138 B2 JPS6325138 B2 JP S6325138B2 JP 1328481 A JP1328481 A JP 1328481A JP 1328481 A JP1328481 A JP 1328481A JP S6325138 B2 JPS6325138 B2 JP S6325138B2
- Authority
- JP
- Japan
- Prior art keywords
- control valve
- oil
- lift
- flow rate
- external hydraulic
- 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
- 238000000605 extraction Methods 0.000 claims description 7
- 239000003921 oil Substances 0.000 description 34
- 230000007935 neutral effect Effects 0.000 description 6
- 238000010586 diagram Methods 0.000 description 3
- 239000010720 hydraulic oil Substances 0.000 description 3
- 239000002699 waste material Substances 0.000 description 1
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B11/00—Servomotor systems without provision for follow-up action; Circuits therefor
- F15B11/16—Servomotor systems without provision for follow-up action; Circuits therefor with two or more servomotors
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B2211/00—Circuits for servomotor systems
- F15B2211/30—Directional control
- F15B2211/31—Directional control characterised by the positions of the valve element
- F15B2211/3105—Neutral or centre positions
- F15B2211/3116—Neutral or centre positions the pump port being open in the centre position, e.g. so-called open centre
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B2211/00—Circuits for servomotor systems
- F15B2211/40—Flow control
- F15B2211/405—Flow control characterised by the type of flow control means or valve
- F15B2211/40507—Flow control characterised by the type of flow control means or valve with constant throttles or orifices
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B2211/00—Circuits for servomotor systems
- F15B2211/40—Flow control
- F15B2211/415—Flow control characterised by the connections of the flow control means in the circuit
- F15B2211/41509—Flow control characterised by the connections of the flow control means in the circuit being connected to a pressure source and a directional control valve
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B2211/00—Circuits for servomotor systems
- F15B2211/40—Flow control
- F15B2211/455—Control of flow in the feed line, i.e. meter-in control
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B2211/00—Circuits for servomotor systems
- F15B2211/50—Pressure control
- F15B2211/505—Pressure control characterised by the type of pressure control means
- F15B2211/50509—Pressure control characterised by the type of pressure control means the pressure control means controlling a pressure upstream of the pressure control means
- F15B2211/50536—Pressure control characterised by the type of pressure control means the pressure control means controlling a pressure upstream of the pressure control means using unloading valves controlling the supply pressure by diverting fluid to the return line
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B2211/00—Circuits for servomotor systems
- F15B2211/50—Pressure control
- F15B2211/505—Pressure control characterised by the type of pressure control means
- F15B2211/50563—Pressure control characterised by the type of pressure control means the pressure control means controlling a differential pressure
- F15B2211/50581—Pressure control characterised by the type of pressure control means the pressure control means controlling a differential pressure using counterbalance valves
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B2211/00—Circuits for servomotor systems
- F15B2211/50—Pressure control
- F15B2211/57—Control of a differential pressure
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B2211/00—Circuits for servomotor systems
- F15B2211/70—Output members, e.g. hydraulic motors or cylinders or control therefor
- F15B2211/71—Multiple output members, e.g. multiple hydraulic motors or cylinders
- F15B2211/7107—Multiple output members, e.g. multiple hydraulic motors or cylinders the output members being mechanically linked
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B2211/00—Circuits for servomotor systems
- F15B2211/70—Output members, e.g. hydraulic motors or cylinders or control therefor
- F15B2211/75—Control of speed of the output member
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B2211/00—Circuits for servomotor systems
- F15B2211/70—Output members, e.g. hydraulic motors or cylinders or control therefor
- F15B2211/78—Control of multiple output members
- F15B2211/781—Control of multiple output members one or more output members having priority
Landscapes
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Fluid Mechanics (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Lifting Devices For Agricultural Implements (AREA)
- Operation Control Of Excavators (AREA)
Description
【発明の詳細な説明】
この発明はトラクタの例えば前部に装着したバ
ケツトローダ或いはフロントリフトの如き作業機
の作動ピストンを動作するのに用いる外部油圧取
出装置の改良に関するものである。DETAILED DESCRIPTION OF THE INVENTION This invention relates to an improvement in an external hydraulic take-off device used to operate the actuating piston of a work implement such as a bucket loader or front lift mounted on the front of a tractor.
従来の外部油圧取出装置は第１図にバケツトロ
ーダの場合の制御回路図を例示したように、ポン
プ１の圧力油をバケツトローダのリフトアーム起
伏動作のための起伏用制御弁２に送油して起伏シ
リンダ３の起伏ピストン３ａを突出、或いは後退
させ、この起伏シリンダ３から排出される圧力油
をバケツト回動動作のためのダンプ用制御弁４に
送油してダンプシリンダ５のダンプピストン５ａ
を突出、或いは後退させてタンク６に戻すように
接続し、又、ポンプ１の圧力油はリフト用制御弁
２の中立油路２ａとダンプ用制御弁４の中立油路
４ａとを経てトラクタの油圧リフト機構を制御す
るためのリフト制御弁７に送られ、リフトシリン
ダ８に供給されるように構成している。そして、
送油配管の数をできるだけ少なくするために、こ
の例示のように作業機の作動制御に用いる起伏用
制御弁２やダンプ用制御弁４等の外部油圧用制御
弁は、夫々の作動油路２ｂ，２ｃと４ｂ，４ｃが
互いに直列に接続されていて、起伏シリンダ３や
ダンプシリンダ５などの作動シリンダも互いに直
列接続であるので、ポンプ１に近い側の前位の作
動シリンダ、例えば起伏シリンダ３の容量やその
作動ピストンの作動速度によつて後位の作動シリ
ンダ例えばダンプシリンダ５の作動ピストンの作
動速度が制約されることになつて、互いに独立
に、夫々に好適な速度で動作できない欠点があ
る。そして前位の作動ピストンは作動速度が過大
となり、或いは後位の作動シリンダに充分な油量
を送るためには前位の作動シリンダを必要以上に
大径に構成しなければならないなどの無駄もあ
る。 As shown in the control circuit diagram for a bucket loader in the conventional external hydraulic pressure extraction device, as shown in FIG. The undulating piston 3a of the cylinder 3 is protruded or retracted, and the pressure oil discharged from the undulating cylinder 3 is sent to the dump control valve 4 for bucket rotation operation, and the dump piston 5a of the dump cylinder 5 is moved.
The pump 1 is connected so as to protrude or retreat and return to the tank 6, and the pressure oil of the pump 1 is connected to the tractor through the neutral oil passage 2a of the lift control valve 2 and the neutral oil passage 4a of the dump control valve 4. It is configured to be sent to a lift control valve 7 for controlling a hydraulic lift mechanism and supplied to a lift cylinder 8. and,
In order to reduce the number of oil supply pipes as much as possible, external hydraulic control valves such as the luffing control valve 2 and the dumping control valve 4 used to control the operation of the work machine are connected to the respective hydraulic oil passages 2b as shown in this example. , 2c and 4b, 4c are connected in series with each other, and working cylinders such as the hoisting cylinder 3 and dump cylinder 5 are also connected in series with each other, so the front working cylinders near the pump 1, such as the hoisting cylinder 3, The operating speed of the operating piston of the rear operating cylinder, for example, the dump cylinder 5, is restricted by the capacity of the cylinder and the operating speed of its operating piston, which has the disadvantage that each cylinder cannot operate independently at its preferred speed. be. There is also waste, such as the front working piston operating at an excessive speed, or the front working cylinder having to have a larger diameter than necessary in order to send a sufficient amount of oil to the rear working cylinder. be.
そこで、この発明は、従来の装置におけるこれ
らの問題を解決せんとして提案せられたものであ
り、夫々の作動ピストンが独立して好適な速度で
動作することができ、且つ、無駄の無い構造の外
部油圧取出装置を提案するために、ポンプ１から
起伏用制御弁２の如き外部油圧用制御弁への送り
側油路９と、これらの外部油圧制御弁からトラク
タのリフトアーム昇降用のリフト用制御弁７への
戻り側油路１０との間に流量制御弁１１を接続
し、且つ、この流量制御弁１１には送り側油路９
の絞りＭにて調整された余剰油を流量制御弁１１
を介して、前記外部油圧制御弁からの戻り側油路
１０に合流せしめて前記トラクタのリフトアーム
昇降用のリフト用制御弁７に送油できるようにし
たことを特徴とするトラクタにおける外部油圧取
出装置を提供せんとするものである。 Therefore, the present invention was proposed to solve these problems in conventional devices, and has a structure in which each working piston can operate independently at a suitable speed, and has a streamlined structure. In order to propose an external hydraulic pressure extraction device, a feed side oil passage 9 from the pump 1 to an external hydraulic pressure control valve such as a hoisting control valve 2, and a lift line from these external hydraulic pressure control valves for raising and lowering a lift arm of a tractor are provided. A flow rate control valve 11 is connected between a return side oil passage 10 to the control valve 7, and a sending side oil passage 9 is connected to this flow rate control valve 11.
Excess oil adjusted by the throttle M is transferred to the flow control valve 11.
External hydraulic pressure extraction for a tractor, characterized in that the oil can be fed to a lift control valve 7 for raising and lowering a lift arm of the tractor by merging with a return side oil passage 10 from the external hydraulic pressure control valve through the oil pressure control valve. The aim is to provide the equipment.
以下、この発明の実施例を別紙添付図面に従つ
て詳述する。尚、説明の都合上、従来公知に属す
る構成も同時に説明する。 Embodiments of the present invention will be described in detail below with reference to the accompanying drawings. For convenience of explanation, conventionally known configurations will also be explained at the same time.
依つて、従来と同様に、ポンプ１の圧力油はバ
ケツトローダの起伏用制御弁２に送油されて、起
伏シリンダ３の起伏ピストン３ａを突出、或は後
退させ、そして、この起伏シリンダ３から排出さ
れる圧力油をダンプ用制御弁４に送油してダンプ
シリンダ５のダンプピストン５ａを突出、或は後
退させてタンク６に戻すのである。更に、ポンプ
１の圧力油はバケツトローダの起伏シリンダ３と
ダンプシリンダ５を作動せしめないときは、前記
リフト用制御弁２の中立油路２ａとダンプ用制御
弁４の中立油路４ａとを経て本機であるトラクタ
に設けられているリフトアーム昇降用のリフト制
御弁７に送油され、リフトアームを昇降させるた
めのリフトシリンダ８に供給せられるように構成
してある。そして、前記起伏用制御弁２やダンプ
用制御弁４等の外部油圧用制御弁は、夫々の作動
油路２ｂ，２ｃと４ｂ，４ｃとが相互に直列に接
続されている。而して、第２図に示すようにポン
プ１から起伏用制御弁２の如き外部油圧用制御弁
への送り側油路９とこれらの外部油圧用制御弁か
らリフト用制御弁７への戻り側油路１０との間に
流量制御弁１１を接続して、送り側油路９を流れ
る圧力油の流量が一定量を越えるとき、この流量
制御弁１１を通つた余剰油は戻り側油路１０から
トラクタのリフトアーム昇降用のリフト用制御弁
７へ送られるように構成し、なお、この流量制御
弁１１は送り側油路９への取出口P1と戻り側油
路１０からの流入口P2とを備えている油圧取出
体１２に内装している。 Therefore, as in the conventional case, the pressure oil of the pump 1 is sent to the hoisting control valve 2 of the bucket troder, causes the hoisting piston 3a of the hoisting cylinder 3 to protrude or retreat, and is then discharged from the hoisting cylinder 3. The pressurized oil is sent to the dump control valve 4, and the dump piston 5a of the dump cylinder 5 is pushed out or retreated, and returned to the tank 6. Further, when the bucket loader's luffing cylinder 3 and dump cylinder 5 are not operated, the pressure oil of the pump 1 is transferred to the main body via the neutral oil passage 2a of the lift control valve 2 and the neutral oil passage 4a of the dump control valve 4. The oil is supplied to a lift control valve 7 for raising and lowering a lift arm provided on a tractor, which is a machine, and is supplied to a lift cylinder 8 for raising and lowering the lift arm. In the external hydraulic pressure control valves such as the uphill control valve 2 and the dump control valve 4, the respective hydraulic oil passages 2b, 2c and 4b, 4c are connected in series. As shown in FIG. 2, there is a feed oil passage 9 from the pump 1 to an external hydraulic pressure control valve such as the hoisting control valve 2, and a return line from these external hydraulic pressure control valves to the lift control valve 7. A flow rate control valve 11 is connected between the side oil passage 10 and when the flow rate of pressure oil flowing through the sending side oil passage 9 exceeds a certain amount, the excess oil passing through this flow rate control valve 11 is transferred to the return side oil passage. 10 to the lift control valve 7 for raising and lowering the lift arm of the tractor, and this flow rate control valve 11 is configured such that the flow is sent from the outlet P 1 to the sending oil passage 9 and from the return oil passage 10. The hydraulic pressure take-out body 12 is equipped with an inlet P2 .
この発明に係る外部油圧取出装置は上述のよう
に外部油圧制御弁の中立油路を経由してトラクタ
のリフトアーム昇降用のリフト用制御弁７にポン
プ１の全流量を供給するように構成し、上記外部
油圧用制御弁の必要なものには流量制御弁を介し
てポンプ１から送油するように構成しているの
で、その作動シリンダの作動ピストンの移動速度
をコントロールするなどの必要のある当該外部油
圧用制御弁には流量制御弁によつて一定量に制限
された圧力油が供給されることになり、作動ピス
トンの移動速度を所定のものとすることができ
る。そして、トラクタのリフトアーム昇降用のリ
フト用制御弁７にはポンプ１の全流量の圧力油が
供給されるので、油圧リフト機構は設定の速度に
て支障なく動作することになるのである。 As described above, the external hydraulic pressure extraction device according to the present invention is configured to supply the entire flow rate of the pump 1 to the lift control valve 7 for raising and lowering the lift arm of the tractor via the neutral oil path of the external hydraulic pressure control valve. Since the above-mentioned external hydraulic pressure control valve is configured to supply oil from the pump 1 via a flow rate control valve, it is necessary to control the moving speed of the operating piston of the operating cylinder. The external hydraulic pressure control valve is supplied with pressure oil that is limited to a certain amount by the flow control valve, so that the moving speed of the actuating piston can be set to a predetermined value. Since the lift control valve 7 for raising and lowering the lift arm of the tractor is supplied with the full flow rate of pressure oil of the pump 1, the hydraulic lift mechanism operates at the set speed without any trouble.
第１図は従来の外部油圧取出装置における回路
図、第２図はこの発明の外部油圧取出装置の実施
例を示す回路図である。
符号説明、１……ポンプ、２……起伏制御弁、
２ａ，４ａ……中立油路、３……起伏シリンダ、
２ｂ，２ｃ，４ｂ，４ｃ……作動油路、３ａ……
起伏ピストン、４……ダンプ用制御弁、５……ダ
ンプシリンダ、５ａ……ダンプピストン、６……
タンク、７……トラクタのリフトアーム昇降用の
リフト用制御弁、８……リフトシリンダ、９……
送り側油路、１０……戻り側油路、１１……流量
制御弁、１２……油圧取出体、P1……取出口、
P2……流入口。
FIG. 1 is a circuit diagram of a conventional external hydraulic pressure extraction device, and FIG. 2 is a circuit diagram showing an embodiment of the external hydraulic pressure extraction device of the present invention. Description of symbols, 1...Pump, 2...Elevation control valve,
2a, 4a... Neutral oil path, 3... Lifting cylinder,
2b, 2c, 4b, 4c...hydraulic oil path, 3a...
Lifting piston, 4... Dump control valve, 5... Dump cylinder, 5a... Dump piston, 6...
Tank, 7... Lift control valve for raising and lowering the lift arm of the tractor, 8... Lift cylinder, 9...
Sending side oil path, 10...Return side oil path, 11...Flow rate control valve, 12...Hydraulic pressure outlet, P1 ...Outlet port,
P 2 ...Inlet.
Claims (1)
用制御弁への送り側油路９と、これらの外部油圧
制御弁からトラクタのリフトアーム昇降用のリフ
ト用制御弁７への戻り側油路１０との間に流量制
御弁１１を接続し、且つ、この流量制御弁１１に
は送り側油路９の絞りＭにて調整された余剰油を
流量制御弁１１を介して、前記外部油圧制御弁か
らの戻り側油路１０に合流せしめて前記トラクタ
のリフトアーム昇降用のリフト用制御弁７に送油
できるようにしたことを特徴とするトラクタにお
ける外部油圧取出装置。1 A sending oil path 9 from the pump 1 to an external hydraulic control valve such as the hoisting control valve 2, and a return oil path from these external hydraulic control valves to the lift control valve 7 for raising and lowering the lift arm of the tractor. A flow rate control valve 11 is connected between the flow rate control valve 10 and the flow rate control valve 11, and surplus oil adjusted by the throttle M of the sending oil passage 9 is supplied to the flow rate control valve 11 via the flow rate control valve 11, and the external hydraulic pressure is controlled. An external hydraulic pressure extraction device for a tractor, characterized in that the oil is made to flow into a return side oil path 10 from the valve so as to be able to send oil to a lift control valve 7 for raising and lowering a lift arm of the tractor.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1328481A JPS57127027A (en) | 1981-01-31 | 1981-01-31 | Taking-out device for external oil pressure |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1328481A JPS57127027A (en) | 1981-01-31 | 1981-01-31 | Taking-out device for external oil pressure |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS57127027A JPS57127027A (en) | 1982-08-07 |
| JPS6325138B2 true JPS6325138B2 (en) | 1988-05-24 |
Family
ID=11828893
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP1328481A Granted JPS57127027A (en) | 1981-01-31 | 1981-01-31 | Taking-out device for external oil pressure |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS57127027A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH02147228U (en) * | 1989-05-17 | 1990-12-13 |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104613029B (en) * | 2015-02-12 | 2016-11-16 | 柏跃龙 | The hydraulic system of Novel movable hoistable platform |
-
1981
- 1981-01-31 JP JP1328481A patent/JPS57127027A/en active Granted
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH02147228U (en) * | 1989-05-17 | 1990-12-13 |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS57127027A (en) | 1982-08-07 |
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