CN102330628B - Method and equipment for detecting oil spraying rule of electric control mono-block pump - Google Patents
Method and equipment for detecting oil spraying rule of electric control mono-block pump Download PDFInfo
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- CN102330628B CN102330628B CN 201010229968 CN201010229968A CN102330628B CN 102330628 B CN102330628 B CN 102330628B CN 201010229968 CN201010229968 CN 201010229968 CN 201010229968 A CN201010229968 A CN 201010229968A CN 102330628 B CN102330628 B CN 102330628B
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Abstract
The invention discloses a method and equipment for detecting the oil spraying rule of an electric control mono-block pump. The equipment comprises a signal conversion module, a processing module and a digital display module, wherein the signal converting module is used for extracting an oil spraying pulse signal from an electromagnetic driving current of a mono-block pump solenoid valve and is converted by a signal to output a converting signal; the signal processing module is connected with the signal acquisition module, is used for processing the converting signal received by the signal acquisition module to acquire characteristics of the signal, digitalizing the signal and outputting the characteristics of the digitalized signal; and the digital display module is connected with the processing module and is used for displaying the characteristics of the digitalized signal, received by the processing signal, so as to represent the oil spraying rule of the electric control mono-block pump. The equipment is small in size and is convenient to move and directly measure. Whether a driving module normally works can be conveniently and quickly judged by detecting characteristics of drive current; and the method and equipment bring great convenient to workers and benefit to save the cost of the equipment and improve the detection efficiency.
Description
Technical field
The present invention relates to technical field of engines, relate in particular to a kind of oil spraying rule of electric control mono-block pump detecting method and equipment.
Background technique
The electronically controlled unit pump injection system is a kind of novel fuel ejecting system of can freedom and flexibility adjusting fuel injection quantity and injection timing, having high injection pressure, its fuel injection processes for diesel engine provides control technique more flexibly, and increased substantially injection pressure, effectively coordinated efficient burning to control with accurate injection process.The accurate measurement of diesel engine monoblock pump Electromagnetic Drive electric current and accurate observation are the important evidence of determining that whether the electronically controlled unit pump driver module works, single pump electromagnetic valve driving pulse width and cycle, and whether the average current size of injection control electric current all works closely bound up with the electronically controlled unit pump driver module.The electronically controlled unit pump jet pressure is higher, fuel oil is controlled more accurate, simultaneously driving current is controlled and required also to want high, in design phase and test and the maintenance stage in the past, mostly adding the highi degree of accuracy current clamp with the highi degree of accuracy oscillograph comes direct-detection and measures its drive current waveform, average current and other jet laws, this method of measurement exists testing apparatus expensive, and is mobile inconvenient, the inconveniences such as complicated operation.
Summary of the invention
The object of the present invention is to provide a kind of oil spraying rule of electric control mono-block pump detecting method and oil spraying rule of electric control mono-block pump detection facility small and exquisite, that be convenient to movement, convenient measurement directly perceived.
In order to achieve the above object, the invention provides a kind of oil spraying rule of electric control mono-block pump detecting method, the method comprises the following steps: a. is from the Electromagnetic Drive current draw fuel injection pulse signal of single pump electromagnetic valve, and carries out the signal conversion; B. process collection signal feature and digitizing through the signal after conversion to described; C. show the signal characteristic after described digitizing, to characterize the fuel injection characteristic of electronically controlled unit pump.
Oil spraying rule of electric control mono-block pump detecting method of the present invention, wherein, described signal characteristic comprises: fuel injection pulse width, the Peak current of driving current, maintenance electric current, and engine speed.
Oil spraying rule of electric control mono-block pump detecting method of the present invention, further, described step b comprises the following steps: b1. catches rising edge and the trailing edge of fuel injection pulse, the collection of commencing signal feature when the rising edge of adjacent two subpulses or the time lag between trailing edge are reduced to predetermined value; B2. according to rising edge and the rising edge of the time lag between trailing edge and adjacent two subpulses or time lag between trailing edge of predetermined number of times continuous acquisition single pulse; Continuous acquisition driving current value in the scheduled time after the rising edge of single pulse occurs, and gather driving current value according to predetermined number of times after this scheduled time; B3. get rising edge and the mean value in the time lag between trailing edge of described single pulse, as fuel injection pulse width; Get the rising edge of described adjacent two subpulses or the mean value in the time lag between trailing edge as fuel injection pulse interval time, and obtain engine speed according to the relation of engine speed and fuel injection pulse interval time; The maximum value of the driving current value that gathers in the scheduled time after the rising edge of getting described single pulse occurs is as the Peak current of driving current; Get the mean value of the driving current value that gathers after the described scheduled time, as the maintenance electric current of driving current; B4. with the signal characteristic digitizing in step b3.
Oil spraying rule of electric control mono-block pump detecting method of the present invention, wherein, described signal conversion comprises that A/D conversion and signal amplify.
The present invention also provides a kind of oil spraying rule of electric control mono-block pump detection facility, comprising: a signal conversion module is used for the Electromagnetic Drive current draw fuel injection pulse signal from single pump electromagnetic valve, through this switching signal of output after the signal conversion; One puocessing module is connected with this signal conversion module, passes through the processing to the switching signal that receives from this signal conversion module, collection signal feature, this digitized signal feature of output after digitizing; And a digital display modular, be connected with this puocessing module, be used for showing the digitized signal feature that receives from this puocessing module, to characterize the fuel injection characteristic of electronically controlled unit pump.
Oil spraying rule of electric control mono-block pump detection facility of the present invention, wherein, described signal characteristic comprises: fuel injection pulse width, the Peak current of driving current, maintenance electric current, and engine speed.
Oil spraying rule of electric control mono-block pump detection facility of the present invention, wherein, described puocessing module comprises: a signal characteristic acquisition module, be used for catching rising edge and the trailing edge of fuel injection pulse, and gather rising edge and the time lag between trailing edge, the rising edge of adjacent two subpulses or the time lag between trailing edge of single pulse according to predetermined number of times, and continuous acquisition driving current value after the scheduled time after the rising edge of single pulse occurs, and the driving current value that gathers according to predetermined number of times after this scheduled time; One computing module, rising edge and the mean value in the time lag between trailing edge for the single pulse of calculating described signal characteristic acquisition module collection, calculate the rising edge of adjacent two subpulses or the mean value in the time lag between trailing edge and according to engine speed and fuel injection pulse interval time concern the calculation engine rotating speed, and calculate the maximum value of the driving current value that gathers in scheduled time after described rising edge in single pulse occurs, the mean value of the driving current value that gathers after the rising edge of individual pulse produces and cross a scheduled time; And a digital module, be used for the signal characteristic digitizing that described computing module is calculated.
Oil spraying rule of electric control mono-block pump detection facility of the present invention, wherein, described signal conversion module comprises an A/D change-over circuit and a signal amplification circuit, is respectively used to described signal from the Electromagnetic Drive current draw is carried out A/D conversion and signal amplification.
Oil spraying rule of electric control mono-block pump detection facility of the present invention, wherein, described puocessing module can be AVR MEGA64 single-chip microcomputer.
Oil spraying rule of electric control mono-block pump detection facility of the present invention, wherein, described digital display modular can be liquid crystal display panel.
By technique scheme, the present invention has following beneficial effect:
Equipment of the present invention small and exquisite, be convenient to mobile, conveniently intuitively measure, both can be used in the laboratory when research and design monoblock pump driver module, solve the problem of testing apparatus deficiency, also can be applied to keep in repair check station.
2. whether the present invention is convenient detects by puocessing module the driver module that the driving current signal feature judges unit-pump system and works, saved and carried the not convenient and complex operation that oscillograph adds current clamp, bring great convenience to the staff, be conducive to solve equipment cost, improve detection efficiency.
Description of drawings
Fig. 1 is the schematic diagram of existing oil spraying rule of electric control mono-block pump detection facility;
Fig. 2 is the flow chart of oil spraying rule of electric control mono-block pump detecting method of the present invention;
Fig. 3 is the structural representation of oil spraying rule of electric control mono-block pump detection facility of the present invention;
Fig. 4 is oil spraying rule of electric control mono-block pump detection facility one embodiment's of the present invention structural representation;
Fig. 5 is the schematic diagram that this embodiment's signal characteristic gathers.
Embodiment
Describe in conjunction with specific embodiments with reference to the accompanying drawings the present invention in detail.
As shown in Figure 2, the flow chart for oil spraying rule of electric control mono-block pump detecting method of the present invention comprises: step S101, from the Electromagnetic Drive current draw fuel injection pulse signal of single pump electromagnetic valve, and carry out the signal conversion; Step S102 processes collection signal feature and digitizing through the signal after conversion to described; And step S103, show the signal characteristic after described digitizing, to characterize the fuel injection characteristic of electronically controlled unit pump.
Wherein, the conversion of the signal in step S101 comprises that A/D conversion and signal amplify.Signal characteristic comprises: fuel injection pulse width, the Peak current of driving current, maintenance electric current, and engine speed.Further, step S102 comprises: step S201 catches rising edge and the trailing edge of fuel injection pulse, the collection of commencing signal feature when the rising edge of adjacent two subpulses or the time lag between trailing edge are reduced to predetermined value; Step S202 is according to rising edge and the rising edge of the time lag between trailing edge and adjacent two subpulses or the time lag between trailing edge of predetermined number of times continuous acquisition single pulse; Continuous acquisition driving current value in the scheduled time after the rising edge of single pulse occurs, and gather driving current value according to predetermined number of times after this scheduled time; Step S203 gets rising edge and the mean value in the time lag between trailing edge of described single pulse, as fuel injection pulse width; Get the rising edge of described adjacent two subpulses or the mean value in the time lag between trailing edge as fuel injection pulse interval time, and obtain engine speed according to the relation of engine speed and fuel injection pulse interval time; The maximum value of the driving current value that gathers in the scheduled time after the rising edge of getting described single pulse occurs is as the Peak current of driving current; Get the mean value of the driving current value that gathers after the described scheduled time, as the maintenance electric current of driving current; Step S204 is with the signal characteristic digitizing that obtains in step S203.
As shown in Figure 3, structural representation for oil spraying rule of electric control mono-block pump detection facility 100 of the present invention, it comprises: a signal conversion module 101 is used for the Electromagnetic Drive current draw fuel injection pulse signal from single pump electromagnetic valve, through this switching signal of output after the signal conversion; One puocessing module 102 is connected with this signal acquisition module, passes through the processing to the switching signal that receives from this signal acquisition module, collection signal feature, this digitized signal feature of output after digitizing; And a digital display modular 103, be connected with this puocessing module, be used for showing the digitized signal feature that receives from this puocessing module, to characterize the fuel injection characteristic of electronically controlled unit pump.
Wherein, this signal conversion module 101 comprises an A/D change-over circuit and a signal amplification circuit, is respectively used to described signal from the Electromagnetic Drive current draw is carried out A/D conversion and signal amplification.The signal characteristic that oil spraying rule of electric control mono-block pump detection facility of the present invention shows comprises: fuel injection pulse width, the Peak current of driving current, maintenance electric current, and engine speed.This described puocessing module 103 comprises: a signal characteristic acquisition module 201, be used for catching rising edge and the trailing edge of fuel injection pulse, and gather rising edge and the time lag between trailing edge, the rising edge of adjacent two subpulses or the time lag between trailing edge of single pulse according to predetermined number of times, and continuous acquisition driving current value after the scheduled time after the rising edge of single pulse occurs, and the driving current value that gathers according to predetermined number of times after this scheduled time; One computing module 202, rising edge and the mean value in the time lag between trailing edge for the single pulse of calculating described signal characteristic acquisition module collection, calculate the rising edge of adjacent two subpulses or the mean value in the time lag between trailing edge and according to engine speed and fuel injection pulse interval time concern the calculation engine rotating speed, and calculate the maximum value of the driving current value that gathers in scheduled time after described rising edge in single pulse occurs, the mean value of the driving current value that gathers after the rising edge of individual pulse produces and cross a scheduled time; And a digital module 203, be used for the signal characteristic digitizing that described computing module is calculated.
As shown in Figure 4, be oil spraying rule of electric control mono-block pump detection facility one embodiment's of the present invention structural representation, comprise an A/D change-over circuit, a signal amplification circuit, an AVR MEGA64 single-chip microcomputer and a liquid crystal display panel.its working procedure is: from Electromagnetic Drive current draw fuel injection pulse signal, carry out A/D conversion and signal amplification by A/D change-over circuit and signal amplification circuit, be input in the AVRMEGA64 single-chip microcomputer, through the processing to signal, gather out signal characteristic, be input to liquid crystal display panel after digitizing, show simultaneously fuel injection pulse width on this liquid crystal display panel, the Peak current of driving current, keep electric current, and engine speed etc., thereby characterize the fuel injection characteristic of electronically controlled unit pump, the mode of the major character data of alternative oscillograph reading current clamp output signal.
As shown in Figure 5, the schematic diagram that gathers for this embodiment's signal characteristic.Use capture function and the clocking capability of TIME3 timer in AVR MEGA64 single-chip microcomputer, catch rising edge and the trailing edge of fuel injection pulse, and calculate the interval T between adjacent twice rising edge of a pulse
iAnd the time lag T between single pulse rising edge and trailing edge
jCome regularly T with the TIME1 timer simultaneously
On averageSo that single-chip microcomputer starts and reads the size of the driving current of collection in the suitable moment, at T
On averageThe lowest high-current value of interior collection is electronically controlled unit pump Peak current I
p, at T
On averageThe current value of rear collection is that electronically controlled unit pump keeps electric current I
h, and calculate the mean value that keeps electric current.And calculate engine speed in the TIME3 timer.
The main algorithm of this embodiment of the invention is as follows:
At first, catch rising edge and the trailing edge of fuel injection pulse, AVR MEGA64 single-chip microcomputer monitors enough hour of pulse spacing, and this moment, engine speed about the 100RPM left and right, began the collection signal feature greatly.Gather single fuel injection pulse width T for 5 times
jInterval T with adjacent two subpulses
i, when rising edge occurs, open another timer simultaneously, timing when rising edge of a pulse begins is at T
On averageThe electric current of interior continuous acquisition fuel injection pulse, and cross T
On averageThe electric current of rear collection fuel injection pulse 5 times.
Then, by the fuel injection pulse width that gathers, calculate the mean value of 5 subpulse width
Calculate simultaneously T
On averageThe current maxima I of interior continuous acquisition fuel injection pulse
pAnd mistake T
On averageThe mean value I of the maintenance electric current of 5 fuel injection pulses of rear collection
h, calculate the time lag T of 5 adjacent two subpulses
iMean value
Then, spray with monoblock pump 4 cylinders and be as the criterion, calculate engine speed according to the relation of engine speed and fuel injection pulse, formula is as follows:
Rotating speed
Fuel injection pulse width also will be changed with actual according to the crystal oscillator frequency design of using single-chip microcomputer and conform to, and the mean value of driving current also will be converted into the corresponding range of 1mv/1A, so that consistent with direct use oscilloscope measurement gained.
At last, more than the fuel injection pulse width that records, the Peak current of driving current, keep electric current, and engine speed outputs on liquid crystal display terminal in the lump and intuitively shows.
This embodiment's measuring range is as follows: (1) engine speed (120～4000r/p); (2) fuel injection pulse width (0～6000us); (3) the driving current size (0～50A).
The above is only preferred embodiment of the present invention, non-limitation protection scope of the present invention, and the equivalent structure that all utilizations specification of the present invention and accompanying drawing content are done changes, and all is contained in protection scope of the present invention.
Claims (10)
1. an oil spraying rule of electric control mono-block pump detecting method, is characterized in that, the method comprises the following steps:
A. from the Electromagnetic Drive current draw fuel injection pulse signal of single pump electromagnetic valve, and carry out the signal conversion;
B. process collection signal feature and digitizing through the signal after conversion to described;
C. show the signal characteristic after described digitizing, to characterize the fuel injection characteristic of electronically controlled unit pump.
2. oil spraying rule of electric control mono-block pump detecting method according to claim 1, is characterized in that, described signal characteristic comprises: fuel injection pulse width, the Peak current of driving current, maintenance electric current, and engine speed.
3. oil spraying rule of electric control mono-block pump detecting method according to claim 1 and 2, is characterized in that, described step b comprises the following steps:
B1. catch rising edge and the trailing edge of fuel injection pulse, begin the collection signal feature when the rising edge of adjacent two subpulses or the time lag between trailing edge are reduced to predetermined value;
B2. according to rising edge and the rising edge of the time lag between trailing edge and adjacent two subpulses or time lag between trailing edge of predetermined number of times continuous acquisition single pulse; Continuous acquisition driving current value in the scheduled time after the rising edge of single pulse occurs, and gather driving current value according to predetermined number of times after this scheduled time;
B3. get rising edge and the mean value in the time lag between trailing edge of described single pulse, as fuel injection pulse width; Get the rising edge of described adjacent two subpulses or the mean value in the time lag between trailing edge as fuel injection pulse interval time, and obtain engine speed according to the relation of engine speed and fuel injection pulse interval time; The maximum value of the driving current value that gathers in the scheduled time after the rising edge of getting described single pulse occurs is as the Peak current of driving current; Get the mean value of the driving current value that gathers after the described scheduled time, as the maintenance electric current of driving current;
B4. with the signal characteristic digitizing in step b3.
4. oil spraying rule of electric control mono-block pump detecting method according to claim 1 and 2, is characterized in that, described signal conversion comprises that A/D conversion and signal amplify.
5. an oil spraying rule of electric control mono-block pump detection facility, is characterized in that, comprising:
One signal conversion module is used for the Electromagnetic Drive current draw fuel injection pulse signal from single pump electromagnetic valve, through this switching signal of output after the signal conversion;
One puocessing module is connected with this signal conversion module, passes through the processing to the switching signal that receives from this signal conversion module, collection signal feature, this digitized signal feature of output after digitizing; And
One digital display modular is connected with this puocessing module, is used for showing the digitized signal feature that receives from this puocessing module, to characterize the fuel injection characteristic of electronically controlled unit pump.
6. oil spraying rule of electric control mono-block pump detection facility according to claim 5, is characterized in that, described signal characteristic comprises: fuel injection pulse width, the Peak current of driving current, maintenance electric current, and engine speed.
7. according to claim 5 or 6 described oil spraying rule of electric control mono-block pump detection facilitys, is characterized in that, described puocessing module comprises:
One signal characteristic acquisition module, be used for catching rising edge and the trailing edge of fuel injection pulse, and gather rising edge and the time lag between trailing edge, the rising edge of adjacent two subpulses or the time lag between trailing edge of single pulse according to predetermined number of times, and continuous acquisition driving current value after the scheduled time after the rising edge of single pulse occurs, and the driving current value that gathers according to predetermined number of times after this scheduled time;
One computing module, rising edge and the mean value in the time lag between trailing edge for the single pulse of calculating described signal characteristic acquisition module collection, calculate the rising edge of adjacent two subpulses or the mean value in the time lag between trailing edge and according to engine speed and fuel injection pulse interval time concern the calculation engine rotating speed, and calculate the maximum value of the driving current value that gathers in scheduled time after described rising edge in single pulse occurs, the mean value of the driving current value that gathers after the rising edge of individual pulse produces and cross a scheduled time; And
One digital module is used for the signal characteristic digitizing that described computing module is calculated.
8. according to claim 5 or 6 described oil spraying rule of electric control mono-block pump detection facilitys, it is characterized in that, described signal conversion module comprises an A/D change-over circuit and a signal amplification circuit, is respectively used to described signal from the Electromagnetic Drive current draw is carried out A/D conversion and signal amplification.
9. according to claim 5 or 6 described oil spraying rule of electric control mono-block pump detection facilitys, is characterized in that, described puocessing module is AVR MEGA64 single-chip microcomputer.
10. according to claim 5 or 6 described oil spraying rule of electric control mono-block pump detection facilitys, is characterized in that, described digital display modular is liquid crystal display panel.
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| CN 201010229968 CN102330628B (en) | 2010-07-13 | 2010-07-13 | Method and equipment for detecting oil spraying rule of electric control mono-block pump |
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| CN 201010229968 CN102330628B (en) | 2010-07-13 | 2010-07-13 | Method and equipment for detecting oil spraying rule of electric control mono-block pump |
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| CN102330628B true CN102330628B (en) | 2013-06-12 |
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Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN201137543Y (en) * | 2008-01-11 | 2008-10-22 | 广西玉柴机器股份有限公司 | Oil jetting pump oil spout rule test stand |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| JPS5970841A (en) * | 1982-10-18 | 1984-04-21 | Hitachi Ltd | Fuel feeder for motorcycle engine |
| US7111460B2 (en) * | 2000-03-02 | 2006-09-26 | New Power Concepts Llc | Metering fuel pump |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN201137543Y (en) * | 2008-01-11 | 2008-10-22 | 广西玉柴机器股份有限公司 | Oil jetting pump oil spout rule test stand |
Non-Patent Citations (1)
| Title |
|---|
| 李正帅.高压共轨式电控燃油喷射系统的计算机仿真.《长安大学学报(自然科学版)》.2002,第22卷(第1期),第66-69页. * |
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