CN103640981A - Crane and device and method for correcting inclination angle of lifting hook of double-winch system of crane - Google Patents
Crane and device and method for correcting inclination angle of lifting hook of double-winch system of crane Download PDFInfo
- Publication number
- CN103640981A CN103640981A CN201310670526.6A CN201310670526A CN103640981A CN 103640981 A CN103640981 A CN 103640981A CN 201310670526 A CN201310670526 A CN 201310670526A CN 103640981 A CN103640981 A CN 103640981A
- Authority
- CN
- China
- Prior art keywords
- suspension hook
- inclination
- angle
- control setup
- obliquity sensor
- 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
Images
Landscapes
- Control And Safety Of Cranes (AREA)
Abstract
The invention discloses a crane and a method and a device for correcting an inclination angle of a lifting hook of a double-winch system of the crane. An inclination-angle sensor is arranged on a cross beam on the inner side of the lifting hook; a control device controls the operation of a main winch system, so that the absolute value of the inclination angle of the lifting hook is larger than a preset angle value; the control device selects a synchronous control mode to lift the lifting hook, takes the absolute value of the inclination angle of the lifting hook and carries out differential operation; when the differential value of the absolute value of the inclination angle of the lifting hook is larger than a set threshold, the control device enables the inclination angle of the lifting hook acquired by the inclination-angle sensor to be multiplied by -1 for correction. The correcting device, the correcting method and the crane disclosed by the invention have the advantages that by automatic identification and correction on the installation direction of the inclination-angle sensor, the operation for guaranteeing the forward direction of the sensor by manual installation is avoided, the installation process of the sensor is simplified, the installation time of the sensor is saved, the problem of the backward direction in manual installation is solved, and the effectiveness and the reliability of synchronous control are ensured.
Description
Technical field
The present invention relates to technical field of engineering machinery, relate in particular to correcting device, method and the hoisting crane at a kind of hoisting crane double hoisting system suspension hook inclination angle.
Background technology
At present, on large-tonnage crawler crane, for improving the load-carrying ability of hoisting crane, adopt double hoisting to drive the suspension hook that hoists simultaneously.Yet because the otherness between double hoisting system causes the operation of double hoisting system asynchronous, and then cause that suspension hook tilts, the wearing and tearing of aggravation steel rope and assembly pulley.For solving hoisting crane double hoisting system, move synchronous problem, proposed mounted angle sensor on suspension hook, the synchronous error of direct-detection double hoisting system operation, implements synchro control based on inclination angle feedback.This Strategy For Synchronization Control can guarantee that system long-play can not form error accumulation, realizes the high level of synchronization of double hoisting system.
Adopt this Strategy For Synchronization Control based on suspension hook inclination angle feedback, require the installation direction position necessary and major-minor elevator of obliquity sensor consistent, now, installation of sensors direction is " forward ", inclination angle feedback is an inverse feedback to control system, and this has just guaranteed that synchronism deviation is more and more less under control system effect.If the position of installation of sensors direction and major-minor elevator is inconsistent, now, installation of sensors direction is " oppositely ", and inclination angle feedback is a positive feed back to control system, and this has just caused synchronism deviation increasing, even causes Hoisting Security accident when serious.
Under different lifting operating modes, crawler crane need to adopt the suspension hook of different tonnages, in the process of changing suspension hook, needs obliquity sensor to be reinstalled on new suspension hook, needs major-minor hoisting rope to be wrapped on suspension hook simultaneously.Because having working specification, the winding position (left chain wheel group or right pulley group) of major-minor hoisting rope in lifting hook pulley group strictly do not limit, this has just caused the installation direction of obliquity sensor often in " oppositely " state, causes synchronism deviation increasing.
Summary of the invention
In view of this, the technical matters that the present invention will solve is to provide the correcting device at a kind of hoisting crane double hoisting system suspension hook inclination angle, and suspension hook angle of inclination is revised.
The correcting device at hoisting crane double hoisting system suspension hook inclination angle, comprising: obliquity sensor and control setup; Described obliquity sensor is arranged on the crossbeam of suspension hook inner side, and the suspension hook angle of inclination of measurement is sent to described control setup; Described control setup is controlled the operation of master winch system, makes suspension hook DIP be greater than default angle value; Described control setup is selected synchro control pattern, controls master winch system and secondary hoisting system lifting hook; The suspension hook angle of inclination that described control setup is measured described obliquity sensor takes absolute value, and carries out calculus of differences; When the difference value of suspension hook angle of inclination absolute value is greater than the threshold value of setting, the suspension hook angle of inclination that described control setup collects described obliquity sensor is multiplied by-1 and is revised, described control setup is implemented synchro control based on revised suspension hook inclination angle value, controls master winch system and secondary hoisting system lifting hook.
According to device of the present invention embodiment, further, described default angle value is 1 °.
According to device of the present invention embodiment, further, the signal that described control setup sends described obliquity sensor carries out filtering processing.
According to device of the present invention embodiment, further, described control setup comprises touch-screen; By described touch-screen, select master mode, and installation of sensors direction and correction result are shown.
A hoisting crane with double hoisting system, comprises the correcting device at the suspension hook inclination angle of hoisting crane double hoisting system as above.
The technical matters that the present invention will solve is to provide the modification method at a kind of hoisting crane double hoisting system suspension hook inclination angle, and suspension hook angle of inclination is revised.
The modification method at hoisting crane double hoisting system suspension hook inclination angle, comprising: obliquity sensor is arranged on the crossbeam of suspension hook inner side, and the suspension hook angle of inclination of measurement is sent to control setup; Described control setup is controlled the operation of master winch system, makes suspension hook DIP be greater than default angle value; Described control setup is selected synchro control pattern, controls master winch system and secondary hoisting system lifting hook; The suspension hook angle of inclination that described control setup is measured described obliquity sensor takes absolute value, and carries out calculus of differences; When the difference value of suspension hook angle of inclination absolute value is greater than the threshold value of setting, the suspension hook angle of inclination that described control setup collects described obliquity sensor is multiplied by-1 and is revised, described control setup is implemented synchro control based on revised suspension hook inclination angle value, controls master winch system and secondary hoisting system lifting hook.
According to one embodiment of the method for the invention, further, described default angle value is 1 °.
According to one embodiment of the method for the invention, further, the signal that described control setup sends described obliquity sensor carries out filtering processing.
According to one embodiment of the method for the invention, further, by described touch-screen, select master mode, and installation of sensors direction and correction result are shown
Correcting device, method and the hoisting crane at hoisting crane double hoisting system suspension hook of the present invention inclination angle, by to the automatic Identification of obliquity sensor installation direction and correction, saved by artificial installation and guaranteed the operation of sensor in " forward ", simplified the installation process of sensor, saved the installation of sensors time, while having avoided artificial installation, there is reverse problem, guaranteed the validity and reliability of synchro control.
Accompanying drawing explanation
In order to be illustrated more clearly in the embodiment of the present invention or technical scheme of the prior art, to the accompanying drawing of required use in embodiment or description of the Prior Art be briefly described below, apparently, accompanying drawing in the following describes is only some embodiments of the present invention, for those of ordinary skills, do not paying under the prerequisite of creative work, can also obtain according to these accompanying drawings other accompanying drawing.
Fig. 1 is according to the schematic diagram of an embodiment of the correcting device at hoisting crane double hoisting system suspension hook of the present invention inclination angle;
Fig. 2 A is the schematic diagram that obliquity sensor forward is installed, and Fig. 2 B is the schematic diagram that obliquity sensor is oppositely installed;
Fig. 3 is according to the diagram of circuit of an embodiment of the correcting device at hoisting crane double hoisting system suspension hook of the present invention inclination angle.
The specific embodiment
With reference to the accompanying drawings the present invention is described more fully, exemplary embodiment of the present invention is wherein described.Below in conjunction with the accompanying drawing in the embodiment of the present invention, the technical scheme in the embodiment of the present invention is clearly and completely described, obviously, described embodiment is only the present invention's part embodiment, rather than whole embodiment.Embodiment based in the present invention, those of ordinary skills, not making the every other embodiment obtaining under creative work prerequisite, belong to the scope of protection of the invention.Below in conjunction with figure and embodiment, technical scheme of the present invention is carried out to many-sided description.
As shown in Figure 1, the correcting device at hoisting crane double hoisting system suspension hook inclination angle comprises: obliquity sensor 1 and control setup 2.Obliquity sensor 1 is arranged on the crossbeam of suspension hook inner side, and the suspension hook angle of inclination of measurement is sent to control setup 2.
Control setup 2 is controlled 3 operations of master winch system, makes suspension hook DIP be greater than 1 °, or the angle value of other settings.Control setup 2 is selected synchro control pattern, controls master winch system 3 and secondary hoisting system 4 lifting hooks.
The suspension hook angle of inclination that control setup 2 is measured obliquity sensor 1 takes absolute value, and carries out calculus of differences.When the difference value of suspension hook angle of inclination absolute value is greater than the threshold value of setting, the suspension hook angle of inclination that control setup 2 collects obliquity sensor is multiplied by-1 and is revised, control setup is implemented synchro control based on revised suspension hook inclination angle value, controls master winch system 3 and secondary hoisting system 4 lifting hooks.
Synchro control pattern refers under this pattern, by controlling when master winch handle can be realized major and minor hoisting system, control, and according to the synchro control error (suspension hook angle of inclination) detecting, regulate the running velocity of major and minor elevator, make major and minor elevator operation synchronous.Under asynchronous master mode, master winch handle can only be controlled the operation of master winch system, the operation of uncontrollable secondary hoisting system.
According to one embodiment of present invention, the signal that 2 pairs of obliquity sensors of control setup 1 send carries out filtering processing.Control setup 2 comprises touch-screen, by touch-screen, selects master mode, and installation of sensors direction and correction result are shown.
According to one embodiment of present invention, a kind of hoisting crane with double hoisting system comprises the correcting device at the suspension hook inclination angle of hoisting crane double hoisting system as above.
According to one embodiment of present invention, the modification method at hoisting crane double hoisting system suspension hook inclination angle comprises: obliquity sensor is arranged on the crossbeam of suspension hook inner side, and the suspension hook angle of inclination of measurement is sent to control setup.
Control setup is controlled the operation of master winch system, makes suspension hook DIP be greater than the angle value of 1 ° or other settings; Control setup is selected synchro control pattern, controls master winch system and secondary hoisting system lifting hook.
The suspension hook angle of inclination that control setup is measured obliquity sensor takes absolute value, and carries out calculus of differences; When the difference value of suspension hook angle of inclination absolute value is greater than the threshold value of setting, the suspension hook angle of inclination that control setup collects obliquity sensor is multiplied by-1 and is revised, then control setup is implemented synchro control based on revised suspension hook inclination angle value, controls master winch system and secondary hoisting system lifting hook.
The installation direction of sensor is relevant to the wiring relation of major-minor elevator.As shown in Figure 2 A and 2B, if the direction of arrow of installation of sensors is pointed to master winch steel rope 22, between sensor and controller, form a degeneration factor, the result of synchro control is the angle of inclination of constantly eliminating suspension hook, finally makes suspension hook pitch angle control near 0 °; If installation of sensors direction is pointed to secondary hoisting rope 23, between sensor and controller, form a positive feedback system, the result of synchro control is that the angle of inclination of suspension hook constantly increases, the operation of double hoisting system is more asynchronous.
As shown in Figure 3, the step of the modification method at hoisting crane double hoisting system suspension hook inclination angle is as follows:
Calculus of differences is a kind of computing for approximate differentiate, and for example, the suspension hook inclination angle value that (sampling time interval is ts) gathers between double sampling is respectively q1 and q2, and calculus of differences is exactly (q2-q1)/ts.
Correcting device, method and the hoisting crane at hoisting crane double hoisting system suspension hook of the present invention inclination angle, by to the automatic Identification of obliquity sensor installation direction and correction, saved by artificial installation and guaranteed the operation of sensor in " forward ", simplified the installation process of sensor.The operating process of automatic Identification and correction, in 30 seconds, has been saved the installation of sensors time greatly; While having avoided artificial installation, there is reverse problem, guaranteed the validity and reliability of synchro control.
The disclosed arbitrary technical scheme of the invention described above unless otherwise stated, if it discloses number range, so disclosed number range is preferred number range, any it should be appreciated by those skilled in the art: preferred number range is only the obvious or representative numerical value of technique effect in many enforceable numerical value.Because numerical value is more, cannot be exhaustive, so the present invention just discloses part numerical value with casehistory technical scheme of the present invention, and the above-mentioned numerical value of enumerating should not form the restriction to the invention protection domain.
May realize in many ways method and system of the present invention.For example, can realize method and system of the present invention by any combination of software, hardware, firmware or software, hardware, firmware.Said sequence for the step of method is only in order to describe, and the step of method of the present invention is not limited to above specifically described order, unless special version otherwise.In addition, in certain embodiments, can be also the program being recorded in recording medium by the invention process, these programs comprise for realizing the machine readable instructions of the method according to this invention.Thereby the present invention also covers storage for carrying out the recording medium of the program of the method according to this invention.
In addition, in the disclosed arbitrary technical scheme of the invention described above applied for the term that represents position relationship or shape unless otherwise stated its implication comprise and its approximate, similar or approaching state or shape.Arbitrary parts provided by the invention can be both to be assembled by a plurality of independent component parts, the produced separate part of the technique that also can be one of the forming.
Finally should be noted that: above embodiment is only in order to illustrate that technical scheme of the present invention is not intended to limit; Although the present invention is had been described in detail with reference to preferred embodiment, those of ordinary skill in the field are to be understood that: still can modify or part technical characterictic is equal to replacement the specific embodiment of the present invention; And not departing from the spirit of technical solution of the present invention, it all should be encompassed in the middle of the technical scheme scope that the present invention asks for protection.
Claims (9)
1. the correcting device at hoisting crane double hoisting system suspension hook inclination angle, is characterized in that, comprising:
Obliquity sensor and control setup;
Described obliquity sensor is arranged on the crossbeam of suspension hook inner side, and the suspension hook angle of inclination of measurement is sent to described control setup;
Described control setup is controlled the operation of master winch system, makes suspension hook DIP be greater than default angle value;
Described control setup is selected synchro control pattern, controls master winch system and secondary hoisting system lifting hook;
The suspension hook angle of inclination that described control setup is measured described obliquity sensor takes absolute value, and carries out calculus of differences; When the difference value of suspension hook angle of inclination absolute value is greater than the threshold value of setting, the suspension hook angle of inclination that described control setup collects described obliquity sensor is multiplied by-1 and is revised, then control setup is implemented synchro control based on revised suspension hook inclination angle value, controls master winch system and secondary hoisting system lifting hook.
2. device as claimed in claim 1, is characterized in that:
Described default angle value is 1 °.
3. device as claimed in claim 2, is characterized in that:
The signal that described control setup sends described obliquity sensor carries out filtering processing.
4. device as claimed in claim 3, is characterized in that:
Described control setup comprises touch-screen;
By described touch-screen, select master mode, and installation of sensors direction and correction result are shown.
5. a hoisting crane with double hoisting system, is characterized in that:
The correcting device that comprises the suspension hook inclination angle of the hoisting crane double hoisting system as described in claim 1 to 4 any one.
6. the modification method at the suspension hook inclination angle of hoisting crane double hoisting system, comprising:
Obliquity sensor is arranged on the crossbeam of suspension hook inner side, and the suspension hook angle of inclination of measurement is sent to control setup;
Described control setup is controlled the operation of master winch system, makes suspension hook DIP be greater than default angle value;
Described control setup is selected synchro control pattern, controls master winch system and secondary hoisting system lifting hook;
The suspension hook angle of inclination that described control setup is measured described obliquity sensor takes absolute value, and carries out calculus of differences; When the difference value of suspension hook angle of inclination absolute value is greater than the threshold value of setting, the suspension hook angle of inclination that described control setup collects described obliquity sensor is multiplied by-1 and is revised, then control setup is implemented synchro control based on revised suspension hook inclination angle value, controls master winch system and secondary hoisting system lifting hook.
7. method as claimed in claim 6, is characterized in that:
Described default angle value is 1 °.
8. method as claimed in claim 7, is characterized in that:
The signal that described control setup sends described obliquity sensor carries out filtering processing.
9. method as claimed in claim 8, is characterized in that:
By described touch-screen, select master mode, and installation of sensors direction and correction result are shown.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201310670526.6A CN103640981B (en) | 2013-12-11 | 2013-12-11 | The correction device at lifting machine double hoisting system suspension hook inclination angle, method and lifting machine |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201310670526.6A CN103640981B (en) | 2013-12-11 | 2013-12-11 | The correction device at lifting machine double hoisting system suspension hook inclination angle, method and lifting machine |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN103640981A true CN103640981A (en) | 2014-03-19 |
| CN103640981B CN103640981B (en) | 2016-06-01 |
Family
ID=50246319
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201310670526.6A Active CN103640981B (en) | 2013-12-11 | 2013-12-11 | The correction device at lifting machine double hoisting system suspension hook inclination angle, method and lifting machine |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN103640981B (en) |
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104609311A (en) * | 2015-02-03 | 2015-05-13 | 徐工集团工程机械股份有限公司 | Dual-winding synchronous control system and dual-winding synchronous control method for crane |
| CN106219410A (en) * | 2016-09-12 | 2016-12-14 | 徐工集团工程机械股份有限公司 | A kind of crawler crane and double hook device for controlling differential speed based on opened loop control thereof |
| CN108946448A (en) * | 2018-08-02 | 2018-12-07 | 河南卫华机械工程研究院有限公司 | A kind of system of crane hook rotational positioning |
| CN110498357A (en) * | 2018-05-18 | 2019-11-26 | 深圳凯世光研股份有限公司 | Hanging method and Lift-on/Lift-off System |
| CN111762706A (en) * | 2020-06-11 | 2020-10-13 | 中联重科股份有限公司 | Double-winch single-hook type lifting equipment and winch synchronous calibration method and system thereof |
| CN113526350A (en) * | 2021-06-17 | 2021-10-22 | 中联重科股份有限公司 | Control method and device for engineering machinery, processor and engineering machinery |
| CN114104978A (en) * | 2021-10-26 | 2022-03-01 | 湖南三一中型起重机械有限公司 | Double-winch synchronous control method and device, operation machine, equipment and medium |
| US11821296B2 (en) | 2021-07-30 | 2023-11-21 | Yantai Jereh Petroleum Equipment & Technologies Co., Ltd. | Mixing and discharging device, mixing and discharging system and fracturing system |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH07125980A (en) * | 1993-11-05 | 1995-05-16 | Kajima Corp | Crane control device with operation state display device |
| CN101704473A (en) * | 2009-11-11 | 2010-05-12 | 甘肃省电力公司刘家峡水电厂 | Main lifting parallel operation height balance correcting system of 400-ton bridge crane |
| CN201834684U (en) * | 2010-09-30 | 2011-05-18 | 三一集团有限公司 | Hoisting equipment and control system of hanger lifting mechanism thereof |
| CN103332604A (en) * | 2013-07-19 | 2013-10-02 | 王转巧 | Using method for ground linkage table operation and control device of large-scale crane |
-
2013
- 2013-12-11 CN CN201310670526.6A patent/CN103640981B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH07125980A (en) * | 1993-11-05 | 1995-05-16 | Kajima Corp | Crane control device with operation state display device |
| CN101704473A (en) * | 2009-11-11 | 2010-05-12 | 甘肃省电力公司刘家峡水电厂 | Main lifting parallel operation height balance correcting system of 400-ton bridge crane |
| CN201834684U (en) * | 2010-09-30 | 2011-05-18 | 三一集团有限公司 | Hoisting equipment and control system of hanger lifting mechanism thereof |
| CN103332604A (en) * | 2013-07-19 | 2013-10-02 | 王转巧 | Using method for ground linkage table operation and control device of large-scale crane |
Cited By (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104609311A (en) * | 2015-02-03 | 2015-05-13 | 徐工集团工程机械股份有限公司 | Dual-winding synchronous control system and dual-winding synchronous control method for crane |
| CN104609311B (en) * | 2015-02-03 | 2016-09-14 | 徐工集团工程机械股份有限公司 | A kind of double hoisting synchronous control system for crane and method |
| CN106219410A (en) * | 2016-09-12 | 2016-12-14 | 徐工集团工程机械股份有限公司 | A kind of crawler crane and double hook device for controlling differential speed based on opened loop control thereof |
| CN106219410B (en) * | 2016-09-12 | 2018-02-27 | 徐工集团工程机械股份有限公司 | A kind of crawler crane and its double hook device for controlling differential speed based on opened loop control |
| CN110498357A (en) * | 2018-05-18 | 2019-11-26 | 深圳凯世光研股份有限公司 | Hanging method and Lift-on/Lift-off System |
| CN108946448A (en) * | 2018-08-02 | 2018-12-07 | 河南卫华机械工程研究院有限公司 | A kind of system of crane hook rotational positioning |
| CN111762706A (en) * | 2020-06-11 | 2020-10-13 | 中联重科股份有限公司 | Double-winch single-hook type lifting equipment and winch synchronous calibration method and system thereof |
| CN111762706B (en) * | 2020-06-11 | 2021-06-15 | 中联重科股份有限公司 | Double-winch single-hook type lifting equipment and winch synchronous calibration method and system thereof |
| CN113526350A (en) * | 2021-06-17 | 2021-10-22 | 中联重科股份有限公司 | Control method and device for engineering machinery, processor and engineering machinery |
| US11821296B2 (en) | 2021-07-30 | 2023-11-21 | Yantai Jereh Petroleum Equipment & Technologies Co., Ltd. | Mixing and discharging device, mixing and discharging system and fracturing system |
| CN114104978A (en) * | 2021-10-26 | 2022-03-01 | 湖南三一中型起重机械有限公司 | Double-winch synchronous control method and device, operation machine, equipment and medium |
Also Published As
| Publication number | Publication date |
|---|---|
| CN103640981B (en) | 2016-06-01 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN103640981A (en) | Crane and device and method for correcting inclination angle of lifting hook of double-winch system of crane | |
| CN106715317B (en) | Operate the method and apparatus and mobilecrane of mobilecrane | |
| CN102807170B (en) | Hoisting crane and double hoisting sync control device, control method | |
| JP4797643B2 (en) | Swivel work machine | |
| CN111042245B (en) | Excavator auxiliary operation control method and system | |
| US10267018B2 (en) | Work vehicle load control system and method | |
| WO2011025197A3 (en) | Automatic operation control device and method for wheel loader work equipment | |
| EP2674326A3 (en) | Device and method for operating a headlight for a motor vehicle | |
| CN104120745B (en) | A kind of excavator automatic land smoothing control method | |
| CN103410183A (en) | Method and system for controlling straight running of bulldozer | |
| AU2019203359A1 (en) | Automatic dig assistance system for a machine | |
| CN106185631A (en) | A kind of rolling control method, device and engineering machinery | |
| EP3228760A1 (en) | Travel control system and method for a work machine | |
| EP2650741A3 (en) | Machine tool | |
| CN103046593B (en) | Perching knife automatic lifting method | |
| CN103982646A (en) | Method and system for controlling active limp home returning mode entering of automatic gearbox | |
| CN106006384A (en) | Lorry crane six-axis gyroscope automatic level detection and leveling system | |
| CN203701186U (en) | Automatic reset control device for walking leg of walking excavator | |
| CN104261257A (en) | Tower crane speed regulating method, device and system | |
| CN103597253B (en) | For method and the transmission control unit of adaptation gearshift | |
| EP2206672A3 (en) | Method and device for monitoring a lift cabin | |
| CN103693559B (en) | A kind of counterweight lifting control method, Apparatus and system | |
| RU2017115479A (en) | Systems and methods for supplying fluid to a long-face development system | |
| CN103872966B (en) | Adopt the method for computer control multispeed electric machine or winding rotor motor speed change | |
| CN104454798B (en) | A kind of control device and control method for offshore spilled oil oil fence automatic distributing and discharging |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant |