CN201339619Y - Multiple-pump working controller, control system and crane - Google Patents
Multiple-pump working controller, control system and crane Download PDFInfo
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- CN201339619Y CN201339619Y CNU2009200057057U CN200920005705U CN201339619Y CN 201339619 Y CN201339619 Y CN 201339619Y CN U2009200057057 U CNU2009200057057 U CN U2009200057057U CN 200920005705 U CN200920005705 U CN 200920005705U CN 201339619 Y CN201339619 Y CN 201339619Y
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Abstract
The utility model discloses a multiple-pump working controller, which comprises a relative parameter signal collecting unit used for obtaining operating signals of each pump, the pressure difference of each hydraulic executing component and the moving speed of an engine and each executing component, a power calculating unit used for calculating the power of each executing component according to the relative parameter, a current power inquiring unit used for inquiring the engine output power under the current rotating speed according to the preset engine power curve table, an overload judging unit used for obtaining the judging results of whether the working states of the multiple pumps are overloaded through taking the condition that whether the power sum value of each executing component is larger than the current engine power, a control signal output unit used for transmitting control signals of simultaneously reducing the delivery capacity of each pump when the judging result representation system is overloaded, and a control parameter storing unit used for storing the relative preset parameters. The utility model further correspondingly discloses a multiple-pump working control system and a crane with the control system.
Description
Technical field
The utility model relates to the automation field of engineering machinery, is specifically related to multi-pump work controller, control system and hoist.
Background technique
Along with the continuous development of construction machinery industry control technique, the energy-conservation and significance that makes full use of power becomes increasingly conspicuous.At present, the Working mechanism of many engineering mechanism all utilizes hydraulic system to drive, and to realize the requirement of various operations, selects closed system to improve system effectiveness in its hydraulic system usually; The problem of thereupon bringing is that hydraulic system has a plurality of oil hydraulic pumps, that is, an operation control loop has an oil hydraulic pump.
With the hoister in large tonnage is example, its key operation by main hoist, mechanisms such as pair hoists, the tower arm hoists, luffing, hoisting arm expansion and revolution realize, each operation control loop of its closed type hydraulic system all has a driving source to be taken from the oil hydraulic pump of motor, or directly driving power taking through power takeoff or through motor, the hydraulic oil of each oil hydraulic pump output certain pressure drives the mechanism kinematic that links with hydraulic actuator.
As everyone knows, the reserve factor of motor can not be too high when power system designs, to adapt to the requirement of energy-saving design.Under the certain prerequisite of engine power, when the working load summation of each pump exceeds the torque range of motor, then need to reduce engine speed, increase the requirement that moment of torsion satisfies moment of torsion; And when rotating speed drops to the max. output torque of motor, can't satisfy the requirement of working load required torque, then engine speed will descend rapidly, until flame-out.Like this, both influenced the working efficiency of operation, and brought inconvenience to the user again, what is more important can influence the working life of motor.
In view of this, how to control the power division between a plurality of oil hydraulic pumps, guarantee the operation of various operation stability and high efficiencies ground, and make engine power be fully used, demand the research staff urgently and propose to solve this case.
The model utility content
At above-mentioned defective, the technical problem that the utility model solves is, a kind of multi-pump work controller is provided, to coordinate the working state between each oil hydraulic pump, when avoiding taking place rotating speed and dropping to the max. output torque of motor, engine speed descends and the occurrence frequency of flame-out situation rapidly, to improve the working life of motor.On this basis, the utility model hoist of a kind of multi-pump work control system also being provided and having this control system.
The multi-pump work controller that the utility model provides, the driving source of a plurality of oil hydraulic pumps of its control all is taken from motor, and the action that is respectively corresponding hydraulic actuator provides power, and this controller comprises:
The relevant parameter signal gathering unit is used to obtain the control signal of each pump, the pressure reduction of each hydraulic actuator and the movement velocity of motor and each executive component;
Power calculation unit is used for calculating according to relevant parameter the power of each executive component;
The current power query unit is used for inquiring about engine output under the current rotating speed according to default engine power curve table;
The overload judging unit, whether greater than present engine performance number be condition, obtain the judged result whether current multi-pump work state transships with the power total value of each executive component if being used for;
The control signal output unit is used for then sending the control signal that reduces each pump displacement simultaneously when described judged result characterization system transships; With
The Control Parameter storage unit is used to store relevant parameter preset.
Preferably, this controller also comprises:
The priority query unit is used for the priority according to each default pump work in combination relation table and each work in combination relation, inquires about the priority relationship between current each pump of working simultaneously;
Whether, with inferior numerical value of the control signal that simultaneously reduce each pump greater than predefined adjustment time numerical value be condition, obtain the judged result whether current adjustment number of times surpasses the adjustment number of times of presetting if adjusting the number of times judging unit; When described judged result characterizes when surpassing default adjustment number of times, the priority relationship between each pump that described control signal output unit obtains according to described inquiry is sent the control signal that stops the low hydraulic pump works of priority.
Preferably, the default adjustment time numerical value of storing in the described Control Parameter storage unit is specially three times.
Preferably, this controller also comprises:
The priority query unit is used for the priority according to each default pump work in combination relation table and each work in combination relation, inquires about the priority relationship between current each pump of working simultaneously;
Maximum Torque output state judging unit, whether be used for the present engine performance number is condition greater than the maximum power value of default engine power curve table, whether obtain present engine is the judged result of Maximum Torque output state; When described judged result characterizes motor is the Maximum Torque output state, and the priority relationship between each pump that described control signal output unit obtains according to described inquiry is sent the control signal that stops the low hydraulic pump works of priority.
Preferably, described control signal output unit is exported described control signal and the described control signal that stops the low hydraulic pump works of priority that reduces each pump control signal in the pulse width modulating signal mode.
The multi-pump work control system that the utility model provides comprises a plurality of oil hydraulic pumps, and the driving source of described a plurality of oil hydraulic pumps all is taken from motor, and the action that is respectively corresponding hydraulic actuator provides power, also comprises: foregoing multi-pump work controller; Effector is used to send control signal to each oil hydraulic pump.
Preferably, described Effector is the Joystick of built-in two two-way angle sensors.
The multi-pump work control system that the utility model provides is specially adapted to hoist applicable to the engineering machinery with many pumps.
The hoist that the utility model provides comprises foregoing multi-pump work control system.
Compared with prior art, the utility model can compare the summation of power that multi-pump work uses and the rated power under the current rotating speed of motor in real time, if the summation of power that current multi-pump work uses is greater than the rated power of motor, then utilize control strategy that each pump is controlled to reduce each pump delivery, reduce many pumps and use the power summation, that is to say, can be in the various loads of many pumps, rotating speed descends and motor carries out power match, engine misses reduce the problem in its working life under the overload working state thereby overcome, and guarantee each composite move proper functioning.The utility model has further solved motor the pump and the motor negative power of hoisting system has been absorbed problem, and lifting motor becomes pump or pump becomes the operating mode of motor, effectively avoids damaging hydraulic element under this dangerous operating mode.This operating mode is the most dangerous operating mode of hydraulic system, causes that easily lifting motor damages, and causes weight gravity decline aloft, and gliding at a high speed causes major accident.
In preferred version of the present utility model,, inquire about the priority relationship between current each pump of working simultaneously according to the priority in each default pump work in combination relation table and each work in combination relation; Whether inferior numerical value by judging the control signal reduce each pump simultaneously greater than the inferior numerical value of predefined adjustment, if then the priority relationship between each pump that obtains according to described inquiry is sent the control signal that stops the low hydraulic pump works of priority.That is to say, after repeatedly reducing each pump displacement, when multiple pump still is in the overload working state, stop the low hydraulic pump works of priority, further reduce and use power, guarantee that multiple pump is in non-overload working state.
In another preferred version of the present utility model, by judging that whether the present engine performance number is greater than the maximum power value in the default engine power curve table, if then send the control signal that stops the low hydraulic pump works of priority.When this scheme can avoid maximum power output still can not satisfy requiring of working load required torque, cause engine speed to descend rapidly and occur, guarantee that motor is in continuous duty until flame-out phenomenon.
Description of drawings
Fig. 1 is first kind of embodiment's composition frame chart of the utility model multi-pump work controller;
Fig. 2 is first kind of embodiment's composition frame chart of the utility model multi-pump work controller;
Fig. 3 is the composition frame chart of multi-pump work control system of the present utility model;
Fig. 4 is the overall structure schematic representation of the hoist that provides of the utility model.
Embodiment
Core of the present utility model is, if the summation of power that current multi-pump work uses is greater than the rated power of motor, then utilize control strategy that each pump is controlled to reduce each pump delivery, reduce many pumps and use the power summation, engine misses reduce the problem in its working life under the overload working state thereby overcome.
Following Specification For Structure accompanying drawing specifies present embodiment.
Existing various engineering machinery all has the several work function, and each actuator adopts multiple combination operating type to increase work efficiency, i.e. composite move.For adopting the Closed Hydraulic control system to realize the engineering machinery of various operations, need to solve between each oil hydraulic pump mutual coordination problems such as power division, otherwise very easily producing between each pump can't co-ordination, even can't mate the problem that causes engine misses with engine output and occur.
Being without loss of generality, is that example describes with the hoist split-pump hydraulic system below.
Hoist has lifting load rating, the several mechanism operation operating mode of high capacity such as work simultaneously, when the mesh power of motor can not satisfy the maximum working load of each combination action, just need coordinate control, make the summation of power that each load is used and the output power of motor be complementary at each oil hydraulic pump that power source is provided for composite move.
Referring to table 1, this has expressed several composite conditions of hoist, and in every kind of composite condition: the oil hydraulic pump that " √ " representative is worked simultaneously, " * " represents the high oil hydraulic pump of priority.
Table 1:
See also Fig. 1, this figure is the schematic representation of a kind of multi-pump work controller of the utility model.Be elaborated below in conjunction with the combination in the table 15, described controller 1 comprises:
Relevant parameter signal gathering unit 11 is used to obtain the control signal of each pump, the pressure reduction of each hydraulic actuator and the movement velocity of motor and each executive component; The relevant parameter signal is specially: the control signal (current signal I2) of the control signal of rotary pump (current signal I1), master file pump, rotary motor pressure reduction δ p1, master file motor pressure reduction δ p2, engine speed n1, rotary motor rotation speed n 2 and master file motor rotary speed n3.
Those of ordinary skill in the art need illustrate, required formula is not further described in aforementioned each calculation procedure, owing to can realize fully based on prior art; Sending control signal with Joystick is example, and wherein, the signal of the discharge capacity of oil pump and handle output is directly proportional, and the discharge capacity that the flow that oil pump flows out equals oil pump multiply by the rotating speed of motor.The power of oil pump is directly proportional with the pressure product of the flow of oil pump, oil pump.The moment of torsion of oil pump is directly proportional with the pressure product of the discharge capacity of oil pump, oil pump.The pressure of oil pump can be by being installed in the pressure of each oil pump outlet.
Current power query unit 13 is used for inquiring about engine output under the current rotating speed according to default engine power curve table; According to the current rotating speed of the motor that is obtained, draw current engine output in conjunction with concrete employed engine power curve table inquiry.Need to prove that predefined engine power curve table is stored based on the power curve of the selected motor of vehicle.
Overload judging unit 14, whether greater than present engine performance number be condition, obtain the judged result whether current multi-pump work state transships with the power total value of each executive component if being used for; That is whether, determine under the working state of present engine, be the overload working state during operation simultaneously of revolution and master file.
Control signal output unit 15 is used for then sending the control signal that reduces each pump displacement simultaneously when described judged result characterization system transships; Based on the judged result of overload judging unit 14,, thereby remove the overload working state if the summation of rotary motor and master file power that motor uses is then sent the control signal that reduces rotary pump and master file pump displacement simultaneously greater than the output power of present engine.
Control Parameter storage unit 16 is used to store relevant parameter preset.Preferably, described Control Parameter storage unit 16 is a readable and writable memory, and be provided with in order to the I/O port of external device communication, thereby be convenient to adjust Control Parameter according to the different system characteristic, improve the versatility of controller 1.
Further, just exist engine output and continue downward trend after repeatedly reducing each pump delivery simultaneously, for avoiding occurring the phenomenon of motor non-normal flameout, this programme selects to stop to carry out composite move, that is, stop the low hydraulic pump works of priority.
Further, as Fig. 2, this controller also comprises:
Certainly, be understandable that, need carry out different combination action priority designs at different types.
Whether, with inferior numerical value of the control signal that simultaneously reduce each pump greater than predefined adjustment time numerical value be condition, obtain the judged result whether current adjustment number of times surpasses the adjustment number of times of presetting if adjusting number of times judging unit 18; When described judged result characterizes when surpassing default adjustment number of times, the priority relationship between each pump that described control signal output unit 15 obtains according to described inquiry is sent the control signal that stops the low hydraulic pump works of priority.Particularly, described predefined adjustment time numerical value is specially three times.
Similarly, described predefined adjustment time numerical value need be set according to the motor reserve factor of different vehicles.
Referring to Fig. 2, this figure is the schematic representation of second kind of multi-pump work controller.Described controller 1 ', comprising:
Relevant parameter signal gathering unit 11 ', be used to obtain the control signal of each pump, the pressure reduction of each hydraulic actuator and the movement velocity of motor and each executive component;
Power calculation unit 12 ', be used for calculating the power of each executive component according to relevant parameter;
Current power query unit 13 ', be used for inquiring about engine output under the current rotating speed according to default engine power curve table;
Overload judging unit 14 ', whether greater than present engine performance number be condition, obtain the judged result whether current multi-pump work state transships with the power total value of each executive component if being used for;
Control signal output unit 15 ', be used for when described judged result characterization system transships, then sending the control signal that reduces each pump displacement simultaneously;
Control Parameter storage unit 16 ', be used to store relevant parameter preset;
Priority query unit 17 ', be used for priority according to each default pump work in combination relation table and each work in combination relation, inquire about the priority relationship between current each pump of working simultaneously; Aforementioned each unit is identical in action principle and its action principle in first embodiment of present embodiment, does not repeat them here.
Maximum Torque output state judging unit 18 ', whether be used for the present engine performance number is condition greater than the maximum power value of default engine power curve table, whether obtain present engine is the judged result of Maximum Torque output state; When described judged result characterizes motor is the Maximum Torque output state, and the priority relationship between each pump of described control signal output unit 15 ' obtain according to described inquiry is sent the control signal that stops the low hydraulic pump works of priority.
The main effect of present embodiment is to be the working state of Maximum Torque output at present engine, if it is the Maximum Torque output state that described judged result characterizes motor, then directly send the control signal that stops the low hydraulic pump works of priority, to avoid taking place engine stalling effectively.
On the basis of above-mentioned two controllers that embodiment provides, increase Effector, a plurality of oil hydraulic pump and corresponding actuator, can control many pumps composite move realizing, be summarized as follows.
See also Fig. 3, this figure is the composition frame chart of multi-pump work control system of the present utility model.This control system comprises: comprise a plurality of oil hydraulic pumps 21,22, the driving source of described a plurality of oil hydraulic pumps 21,22 all is taken from motor, and the action that is respectively corresponding hydraulic actuator provides power, also comprises: foregoing multi-pump work controller 1; Effector 31,32 is used to send control signal to each oil hydraulic pump 21,22.Preferably, each oil hydraulic pump adopts electric ratio control mode, and described Effector is the Joystick of built-in two two-way angle sensors; Along with the variation of handle position, the output relevant pulse width modulation signals, the dutycycle of this signal changes with the change in location of handle; By amplifying this signal and drive the electric proportion electro-magnet of variable displacement pump, thus the discharge capacity of control oil pump.
Particularly; controller 1 ' detect each relevant parameter signal in real time by the CAN bus system; when exceeding predefined scope; calculate the proportional electromagnetic valve of output corresponding control current signal by PID to the hydraulic system variable displacement pump; this valve is by the stable state pressure reduction of controlled variable pump load-sensing valve both sides; realize the pivot angle of control pump; with the control pump delivery; thereby can realize reducing the moment of torsion that pump absorbs; go up to the scope that allows until engine speed; guarantee that flame-out phenomenon can not appear in motor in the course of the work, to adapt to and to protect motor.In addition, when the power of motor is more than needed, can also improve the movement velocity of operation mechanism, to raise the efficiency by control system.
See also Fig. 4, this figure is the overall structure schematic representation of the hoist that provides of the utility model.This hoist comprises foregoing multi-pump work control system.Need to prove that other main function components such as the chassis of this hoist, turntable, power system, hoisting system and Lifting device are not the inventive point places of this patent, do not repeat them here.
The above only is a preferred implementation of the present utility model; should be pointed out that for those skilled in the art, under the prerequisite that does not break away from the utility model principle; can also make some improvements and modifications, these improvements and modifications also should be considered as protection domain of the present utility model.
Claims (8)
1, multi-pump work controller, the driving source of described a plurality of oil hydraulic pumps all is taken from motor, and the action that is respectively corresponding hydraulic actuator provides power, it is characterized in that this controller comprises:
The relevant parameter signal gathering unit is used to obtain the control signal of each pump, the pressure reduction of each hydraulic actuator and the movement velocity of motor and each executive component;
Power calculation unit is used for calculating according to relevant parameter the power of each executive component;
The current power query unit is used for inquiring about engine output under the current rotating speed according to default engine power curve table;
The overload judging unit, whether greater than present engine performance number be condition, obtain the judged result whether current multi-pump work state transships with the power total value of each executive component if being used for;
The control signal output unit is used for then sending the control signal that reduces each pump displacement simultaneously when described judged result characterization system transships; With
The Control Parameter storage unit is used to store relevant parameter preset.
2, multi-pump work controller according to claim 1 is characterized in that, also comprises:
The priority query unit is used for the priority according to each default pump work in combination relation table and each work in combination relation, inquires about the priority relationship between current each pump of working simultaneously;
Whether, with inferior numerical value of the control signal that simultaneously reduce each pump greater than predefined adjustment time numerical value be condition, obtain the judged result whether current adjustment number of times surpasses the adjustment number of times of presetting if adjusting the number of times judging unit; When described judged result characterizes when surpassing default adjustment number of times, the priority relationship between each pump that described control signal output unit obtains according to described inquiry is sent the control signal that stops the low hydraulic pump works of priority.
3, multi-pump work controller according to claim 2 is characterized in that, the default adjustment time numerical value of storing in the described Control Parameter storage unit is specially three times.
4, multi-pump work controller according to claim 1 is characterized in that, also comprises:
The priority query unit is used for the priority according to each default pump work in combination relation table and each work in combination relation, inquires about the priority relationship between current each pump of working simultaneously;
Maximum Torque output state judging unit, whether be used for the present engine performance number is condition greater than the maximum power value of default engine power curve table, whether obtain present engine is the judged result of Maximum Torque output state; When described judged result characterizes motor is the Maximum Torque output state, and the priority relationship between each pump that described control signal output unit obtains according to described inquiry is sent the control signal that stops the low hydraulic pump works of priority.
5, according to the described multi-pump work controller of arbitrary claim in the claim 1 to 4, it is characterized in that described control signal output unit is exported described control signal and the described control signal that stops the low hydraulic pump works of priority that reduces each pump control signal in the pulse width modulating signal mode.
6, multi-pump work control system comprises a plurality of oil hydraulic pumps, and the driving source of described a plurality of oil hydraulic pumps all is taken from motor, and the action that is respectively corresponding hydraulic actuator provides power, it is characterized in that, also comprises:
As the described multi-pump work controller of arbitrary claim in the claim 1 to 5;
Effector is used to send control signal to each oil hydraulic pump.
According to the described multi-pump work control system of claim 6, it is characterized in that 7, described Effector is the Joystick of built-in two two-way angle sensors.
8, hoist is characterized in that, comprises multi-pump work control system as claimed in claim 6.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNU2009200057057U CN201339619Y (en) | 2009-02-06 | 2009-02-06 | Multiple-pump working controller, control system and crane |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNU2009200057057U CN201339619Y (en) | 2009-02-06 | 2009-02-06 | Multiple-pump working controller, control system and crane |
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| CN201339619Y true CN201339619Y (en) | 2009-11-04 |
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| CNU2009200057057U Expired - Lifetime CN201339619Y (en) | 2009-02-06 | 2009-02-06 | Multiple-pump working controller, control system and crane |
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101799022B (en) * | 2009-02-06 | 2011-04-06 | 徐州重型机械有限公司 | Multi-pump work control method, controller and control system and crane |
| WO2013004022A1 (en) * | 2011-07-07 | 2013-01-10 | 长沙中联重工科技发展股份有限公司 | Method and system for controlling rotary movement of rotary crane |
| WO2013152575A1 (en) * | 2012-04-12 | 2013-10-17 | 中联重科股份有限公司 | Method and system for telescopic follow control of boom |
| CN103896168A (en) * | 2013-09-11 | 2014-07-02 | 徐州徐工随车起重机有限公司 | Automatic leveling system of aerial platform of hybrid cantilever crane, aerial platform and leveling method |
-
2009
- 2009-02-06 CN CNU2009200057057U patent/CN201339619Y/en not_active Expired - Lifetime
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101799022B (en) * | 2009-02-06 | 2011-04-06 | 徐州重型机械有限公司 | Multi-pump work control method, controller and control system and crane |
| WO2013004022A1 (en) * | 2011-07-07 | 2013-01-10 | 长沙中联重工科技发展股份有限公司 | Method and system for controlling rotary movement of rotary crane |
| WO2013152575A1 (en) * | 2012-04-12 | 2013-10-17 | 中联重科股份有限公司 | Method and system for telescopic follow control of boom |
| CN103896168A (en) * | 2013-09-11 | 2014-07-02 | 徐州徐工随车起重机有限公司 | Automatic leveling system of aerial platform of hybrid cantilever crane, aerial platform and leveling method |
| CN103896168B (en) * | 2013-09-11 | 2016-02-17 | 徐州徐工随车起重机有限公司 | Mix the automatic horizontal control system of jib aerial platform, Operation Van and leveling method |
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Legal Events
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| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| AV01 | Patent right actively abandoned |
Granted publication date: 20091104 Effective date of abandoning: 20090206 |