CN105782049B - The conjugation measuring system and measuring method of a kind of rotary compressor frictional behavior - Google Patents
The conjugation measuring system and measuring method of a kind of rotary compressor frictional behavior Download PDFInfo
- Publication number
- CN105782049B CN105782049B CN201610235258.9A CN201610235258A CN105782049B CN 105782049 B CN105782049 B CN 105782049B CN 201610235258 A CN201610235258 A CN 201610235258A CN 105782049 B CN105782049 B CN 105782049B
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- torque
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- compressor
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Classifications
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
- F04C28/00—Control of, monitoring of, or safety arrangements for, pumps or pumping installations specially adapted for elastic fluids
- F04C28/28—Safety arrangements; Monitoring
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
- F04B51/00—Testing machines, pumps, or pumping installations
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
- F04C2270/00—Control; Monitoring or safety arrangements
- F04C2270/16—Wear
- F04C2270/165—Controlled or regulated
Abstract
The present invention provides a kind of the conjugation measuring system and measuring method of rotary compressor frictional behavior, belongs to mechanical system field of measuring technique.The present invention is based on " conjugation dynamometry principle ", a conjugation torque is produced using torquer and apply it in the rotating shaft of tested compressor, the conjugation torque and expansion torque caused by tested compressor operating intracavitary are equivalent, reverse and synchronous, it can cancel out each other, so as to isolate moment of friction of the tested compressor in rotation process, the relation of moment of friction and tested compressor rotary speed, atmospheric pressure, corner, time etc. are further measured.Instant invention overcomes isolating the shortcomings of frictional force is difficult, simulated experiment mensuration simulation operating mode and kinematic pair and actual error is big on compressor body, and have the characteristics that measurement error is small, influence factor specification of variables is reliable.
Description
【Technical field】
The present invention relates to the field of measuring technique of mechanical system, more particularly to a kind of conjugation of rotary compressor frictional behavior
Measuring system and measuring method.
【Background technology】
Rotary compressor is a kind of typical volumes formula fluid machinery for having a large capacity and a wide range and influenceing depth, is widely used in various
Gas compressing equipment and refrigerating air conditioning device.For a long time, it is low short with service life to there is mechanical efficiency in rotary compressor always
The defects of, reason is the multiple kinematic pairs for easily deriving from friction and wear of such compressor generally existing, wants to improve rotation
The mechanical efficiency and service life of compressor, just must try to reduce the fretting wear of its kinematic pair, and realize this target,
It then have to be understood that the frictional behavior of rotary compressor.
The factors such as the frictional behavior of rotary compressor and compressor rotary speed, atmospheric pressure, lubrication state, temperature are relevant, existing
Frictional behavior measuring method mainly take simulated experiment mensuration, i.e. certain kinematic pair of analog compression machine under actual condition
Motion conditions, the frictional behavior of independent measurement gym suit.But there are shortcomings in these measuring methods：(1) pressure of simulation
There is very big error in contracting machine actual condition, usually only consider analog compression machine rotating speed, atmospheric pressure, lubrication state, temperature etc.
The influence of some factors therein, it is impossible to consider comprehensively；(2) individually simulate to do the movement pair surface tested and actual motion
Secondary surface difference is too big.Therefore, the key of frictional behavior e measurement technology is to ensure that experiment condition is consistent with actual condition as far as possible,
Preferably tested on compressor body, but isolate on compressor body that frictional force difficulty is larger, and the present invention provides one
Kind measures the measuring method of frictional behavior on compressor body.
【The content of the invention】
The goal of the invention of the present invention is：For above-mentioned problem, there is provided a kind of rotary compressor frictional behavior
It is conjugated measuring system and measuring method.Measuring system is based on " conjugation dynamometry principle ", i.e., produces one altogether using torquer
Yoke torque is simultaneously applied it in the rotating shaft of tested compressor, and the conjugation torque derives from tested compressor operating intracavitary working medium
Torque is equivalent, reverse and synchronous, is cancelled out each other with the gas expansion torque of tested compressor, so as to isolate moment of friction,
Further measure the relation of moment of friction and tested compressor rotary speed, atmospheric pressure, corner, time etc..Instant invention overcomes pressing
The shortcomings of frictional force is difficult, simulated experiment mensuration simulation operating mode and kinematic pair and actual error is big is isolated on contracting machine body, and
And have the characteristics that measurement error is small, influence factor specification of variables is reliable.
To achieve these goals, the technical solution adopted by the present invention is as follows：
A kind of conjugation measuring system of rotary compressor frictional behavior, including operational module, measurement module and control module,
The operational module includes DC servo motor, tested compressor, torquer and source of the gas feeder, the DC servo electricity
Coaxial concatenation and the run-in synchronism successively of machine, tested compressor and torquer, source of the gas feeder are connected with tested compressor；Institute
Stating measurement module includes micro-torque sensor, photoelectric encoder and high-torque sensor, and the high-torque sensor is co-axially mounted
Between torquer and tested compressor；The micro-torque sensor is coaxially mounted to tested compressor and DC servo electricity
Between machine；The photoelectric encoder is arranged on tested compressor close to micro-torque sensor side；The control module includes：PC
Mechanical, electrical machine controller and load modulator, the conjugation power for the compressor difference corner that the load modulator is set according to PC
Square and the operation of control moment generator, the rotating speed for the different corners that electric machine controller is set according to PC simultaneously control DC servo electric
Machine is run；The PC is connected with DC servo motor, is run by motor controller controls direct current generator；PC supplies with source of the gas
Connected to device, by controlling source of the gas feeder to produce atmospheric pressure to act on tested compressor；Micro-torque in the measurement module
Sensor, photoelectric encoder and high-torque sensor are connected with PC respectively.
A kind of measuring method of rotary compressor frictional behavior, comprises the following steps：
(1) the maximum conjugation torque of corner, the angular signal that the source of the gas feeder is sent according to PC, output pressure are measured
Power, act the corresponding gas expansion torque in compressor main shaft so that tested compressor has rotation trend, and PC is according to power
The moment values of square sensor feedback main-axis end set conjugation torque corresponding to this corner, and control load modulator produces conjugation
Torque is with the torque of balancing main shaft shaft end, and control moment generator is stepped up being conjugated moment values to tested compressor on PC
Interior static friction torque disappears, and PC record torquer output conjugation torque size is as the maximum conjugation torque of corner；
(2) corner size (numerical value) is changed, the process in repeat step (1), PC records preserve tested compressor whole
The maximum conjugation torque of different corners in swing circle；
(3) moment of friction is measured, the PC exports the rotating speed of setting by motor controller controls DC servo motor,
PC obtains the speed of mainshaft and corner of tested compressor by photoelectric encoder measurement, and PC feeds back according to photoelectric encoder
Data produce the conjugation torque of corresponding corner through load modulator control moment generator, while control the generation pair of source of the gas feeder
Answer the expansive force of corner, the speed of mainshaft of tested compressor is steadily reached, the PC according to micro-torque sensor measure by
Moment of friction in measured compressed machine rotation process, as moment of friction corresponding to corner and the rotating speed；
(4) PC sets multiple different tachometer values, the process of repeat step (3), draws the friction under corresponding rotating speed
Torque, corner, the numerical value set in advance for expanding atmospheric pressure p corresponding to torque, PC are surveyed according under multiple different tachometer values
Finally fitting draws moment of friction and corner, time t, atmospheric pressure p, the relation curve of rotating speed to the parameter value measured.
Further, the electric machine controller, DC servo motor and photoelectric encoder form a closed-loop control system.
Further, the PC using virtual instrument software Lab VIEW structure software platform, be programmed, show and
Processing.
In summary, by adopting the above-described technical solution, the beneficial effects of the invention are as follows：
(1) present invention is using conjugation dynamometry principle, and torquer produces conjugation torque and the gas of tested compressor is swollen
Expansive force square is cancelled out each other, and so as to isolate moment of friction, is overcome frictional force difficulty is isolated on true compressor the problem of.
(2) present invention measures in the enterprising Mobile state of real rotary compressor, overcomes simulated experiment mensuration simulation work
The shortcomings of condition and kinematic pair and big actual error.
(3) present invention is exported using torque output, atmospheric pressure output, rotating speed, and closed-loop system is more used in rotating speed output,
So that the conjugation torque of setting, atmospheric pressure, the relation of rotating speed and corner can be better controled over and fed back, with measurement error it is small,
The influence factor specification of variables feature such as reliably.
(4) present invention determines compressor frictional force using the multifactor whole dynamic change such as atmospheric pressure, rotating speed, and can be real
When show the relation curve of frictional force and atmospheric pressure, rotating speed etc., friction measurement is more comprehensively, fast.
【Brief description of the drawings】
Fig. 1 is a kind of construction module arrangement schematic diagram of conjugation measuring system of rotary compressor frictional behavior of the present invention.
Fig. 2 is a kind of operation principle schematic diagram of the measuring method of rotary compressor frictional behavior of the present invention.
Items in accompanying drawing illustrate：
1- DC servo motors；2- micro-torque sensors；3- photoelectric encoders；The tested compressors of 4-；5- high-torques sense
Device；6- torquers；7- load modulators；8- source of the gas feeders；9- electric machine controllers；10-PC machines.
【Embodiment】
The present invention is explained in detail below against accompanying drawing and with reference to optimal embodiment.
Fig. 1 is that a kind of construction module of the conjugation measuring system of rotary compressor frictional behavior of the present invention arranges schematic diagram.
As shown in figure 1, a kind of conjugation measuring system of rotary compressor frictional behavior, including operational module, measurement module and control mould
Block, the operational module includes DC servo motor 1, tested compressor 4, torquer 6 and source of the gas feeder 8, described straight
Coaxial concatenation and the run-in synchronism successively of flow servo motor 1, tested compressor 4 and torquer 6, source of the gas feeder 8 with it is tested
Compressor 4 connects；The measurement module includes micro-torque sensor 2, photoelectric encoder 3 and high-torque sensor 5, it is described energetically
Square sensor 5 is coaxially mounted between torquer 6 and tested compressor 4；The micro-torque sensor 2 be coaxially mounted to by
Between measured compressed machine 4 and DC servo motor 1；The photoelectric encoder 3 is arranged on tested compressor 4 close to micro-torque sensor
2 sides；The control module includes：PC 10, electric machine controller 9 and load modulator 7, the load modulator 7 is according to PC
The conjugation torque and control moment generator 6 for the 4 different corners of tested compressor that machine 10 is set are run, the basis of electric machine controller 9
The rotating speed for the different corners that PC 10 is set simultaneously controls DC servo motor 1 to run；The PC 10 connects with DC servo motor 1
Connect, control DC servo motor 1 to run by electric machine controller 9；PC 10 is connected with source of the gas feeder 8, by controlling source of the gas
Feeder 8 produces atmospheric pressure to act on tested compressor 4；Micro-torque sensor 2, photoelectric encoder 3 in the measurement module
It is connected respectively with PC 10 with high-torque sensor 5.
Fig. 2 is a kind of operation principle schematic diagram of the measuring method of rotary compressor frictional behavior of the present invention.Such as Fig. 2 institutes
Show, a kind of measuring method of rotary compressor frictional behavior, the measuring method comprises the following steps：
(1) the maximum conjugation torque of corner, the angular signal that the source of the gas feeder 8 is sent according to PC 10, output are measured
Atmospheric pressure, acting the corresponding gas expansion torque in the tested main shaft of compressor 4 so that tested compressor 4 has rotation trend,
PC 10 is conjugated torque, and control load according to corresponding to the moment values of the feedback main-axis end of torque sensor 5 set this corner
Modulator 7 produces conjugation torque with the torque of balancing main shaft shaft end, and control moment generator 6 is stepped up being conjugated on PC 10
Static friction torque in moment values to tested compressor 4 disappears, and PC is gradually increased value, until, now compressor is inoperative, and
In the absence of static friction torque, because conjugation both torque and gas expansion torque are cancelled out each other.PC 10 records torquer 6
Output conjugation torque size is as the maximum conjugation torque of corner；
(2) corner size (numerical value) is changed, the process in repeat step (1), PC record preserves tested compressor whole
The maximum conjugation torque of different corners in individual swing circle；
(3) moment of friction is measured, the PC exports the rotating speed of setting by motor controller controls DC servo motor,
PC obtains the speed of mainshaft and corner of tested compressor 4 by the measurement of photoelectric encoder 3, and PC 10 is according to photoelectric encoder 3
The data of feedback produce the conjugation torque of corresponding corner through the control moment generator 6 of load modulator 7, while control source of the gas to supply
Device 8 produces the expansive force of corresponding corner, the speed of mainshaft of tested compressor 4 is steadily reached, the PC passes according to micro-torque 2
Sensor measures the moment of friction in the tested rotation process of compressor 4, as moment of friction corresponding to corner and the rotating speed；
(4) PC sets multiple different tachometer values, the process of repeat step (3), draws the friction under corresponding rotating speed
Torque, corner, the numerical value set in advance for expanding atmospheric pressure p corresponding to torque, PC 10 is according under multiple different tachometer values
Measuring obtained parameter value, finally fitting draws moment of friction and corner, atmospheric pressure p, the relation curve of rotating speed.
The electric machine controller 9, DC servo motor 1 and photoelectric encoder 3 form a closed-loop control system, make tested
The speed of mainshaft of compressor 4 is steadily reached, and the PC 10 is carried out using virtual instrument software Lab VIEW structure software platforms
Programming, display and processing.
Claims (4)
1. a kind of conjugation measuring system of rotary compressor frictional behavior, including operational module, measurement module and control module, its
It is characterised by：The operational module includes DC servo motor, tested compressor, torquer and source of the gas feeder, described
Coaxial concatenation and the run-in synchronism successively of DC servo motor, tested compressor and torquer, source of the gas feeder with by pressure measurement
Contracting machine connects；The measurement module includes micro-torque sensor, photoelectric encoder and high-torque sensor, the high-torque sensing
Device is coaxially mounted between torquer and tested compressor；The micro-torque sensor be coaxially mounted to tested compressor and
Between DC servo motor；The photoelectric encoder is arranged on tested compressor close to micro-torque sensor side；The control
Module includes PC, electric machine controller and load modulator, and the PC is connected by load modulator with torquer, institute
The conjugation Torque Control torquer operation for the compressor corner that load modulator is set according to PC is stated, the PC passes through
Electric machine controller is connected with DC servo motor, and the rotating speed for the corner that electric machine controller is set according to PC simultaneously controls DC servo
Motor operation；PC is connected with source of the gas feeder, by controlling source of the gas feeder to produce atmospheric pressure to act on tested compressor；
Micro-torque sensor, photoelectric encoder and high-torque sensor in the measurement module are connected with PC respectively.
2. a kind of measuring method of the conjugation measuring system of the frictional behavior of rotary compressor according to claim 1, its feature
It is：It comprises the following steps：（1）The maximum conjugation torque of measurement corner, the angular signal that source of the gas feeder is sent according to PC,
Output pressure power, act the corresponding gas expansion torque in compressor main shaft so that tested compressor has rotation trend, PC
Machine is conjugated torque, and control moment according to corresponding to the moment values of high-torque sensor feedback main-axis end set this angular signal
Generator produces conjugation torque with the torque of balancing main shaft shaft end, and control moment generator is stepped up being conjugated torque on PC
Be worth in tested compressor static friction torque disappear, PC record torquer output conjugation torque size as corner most
Big conjugation torque；
（2）Change angular signal size, the process in repeat step (1), PC records preserve tested compressor in whole revolution
The maximum conjugation torque of different angular signals in phase；
(3) moment of friction is measured, the PC exports the rotating speed of setting, PC by motor controller controls DC servo motor
The speed of mainshaft and corner of tested compressor, the data that PC feeds back according to photoelectric encoder are obtained by photoelectric encoder measurement
The conjugation torque of corresponding corner is produced through load modulator control moment generator, while controls source of the gas feeder to produce corresponding turn
The expansive force at angle, the speed of mainshaft of tested compressor is set steadily to reach, the PC is measured by pressure measurement according to micro-torque sensor
Moment of friction in contracting machine rotation process, as moment of friction corresponding to corner and the rotating speed；
(4) PC sets multiple different tachometer values, the process of repeat step (3), draws the frictional force under corresponding rotating speed
Square, corner, the numerical value set in advance for expanding atmospheric pressure p corresponding to torque, PC measure according under multiple different tachometer values
Finally fitting draws moment of friction and corner, atmospheric pressure p, the relation curve of rotating speed to obtained parameter value.
3. the measuring method of the conjugation measuring system of rotary compressor frictional behavior according to claim 2, it is characterised in that：
The electric machine controller, DC servo motor and photoelectric encoder form a closed-loop control system.
4. the measuring method of the conjugation measuring system of rotary compressor frictional behavior according to claim 2, it is characterised in that：
The PC is programmed, shown and processing using virtual instrument of LabVIEW structure software platform.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201610235258.9A CN105782049B (en) | 2016-04-14 | 2016-04-14 | The conjugation measuring system and measuring method of a kind of rotary compressor frictional behavior |
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| CN201610235258.9A CN105782049B (en) | 2016-04-14 | 2016-04-14 | The conjugation measuring system and measuring method of a kind of rotary compressor frictional behavior |
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| CN105782049B true CN105782049B (en) | 2018-01-12 |
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| CN106768566B (en) * | 2017-03-15 | 2023-05-05 | 广西大学 | Friction force measuring device for sliding vane and sliding chute of rolling piston compressor |
| CN113107834B (en) * | 2021-05-14 | 2022-04-29 | 浙江大学 | Non-invasive axial plunger pump cylinder dynamic characteristic measuring method |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102507435A (en) * | 2011-12-01 | 2012-06-20 | 中联重科股份有限公司 | Friction coefficient measurement method |
| CN102518582A (en) * | 2011-12-09 | 2012-06-27 | 中国兵器工业集团第七○研究所 | Abrasion test device for gas compressor |
| EP2796719A1 (en) * | 2013-04-22 | 2014-10-29 | Kabushiki Kaisha Kobe Seiko Sho (Kobe Steel, Ltd.) | Gas compressor and abrasion state determining method |
| CN104236885A (en) * | 2014-09-04 | 2014-12-24 | 广西大学 | System for testing relation of speeds and friction force between rotary compressor blade and end covers |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20000040677A (en) * | 1998-12-19 | 2000-07-05 | 전주범 | Device and method for measuring frictional loss of shaft for airtight compressor |
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Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102507435A (en) * | 2011-12-01 | 2012-06-20 | 中联重科股份有限公司 | Friction coefficient measurement method |
| CN102518582A (en) * | 2011-12-09 | 2012-06-27 | 中国兵器工业集团第七○研究所 | Abrasion test device for gas compressor |
| EP2796719A1 (en) * | 2013-04-22 | 2014-10-29 | Kabushiki Kaisha Kobe Seiko Sho (Kobe Steel, Ltd.) | Gas compressor and abrasion state determining method |
| CN104236885A (en) * | 2014-09-04 | 2014-12-24 | 广西大学 | System for testing relation of speeds and friction force between rotary compressor blade and end covers |
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