CN107192547A - A kind of diesel locomotive unit brake testing stand - Google Patents
A kind of diesel locomotive unit brake testing stand Download PDFInfo
- Publication number
- CN107192547A CN107192547A CN201710537697.XA CN201710537697A CN107192547A CN 107192547 A CN107192547 A CN 107192547A CN 201710537697 A CN201710537697 A CN 201710537697A CN 107192547 A CN107192547 A CN 107192547A
- Authority
- CN
- China
- Prior art keywords
- testing stand
- unit brake
- diesel locomotive
- locomotive unit
- brake testing
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- 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.)
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Classifications
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
- G01M13/00—Testing of machine parts
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
- G01M3/00—Investigating fluid-tightness of structures
- G01M3/02—Investigating fluid-tightness of structures by using fluid or vacuum
- G01M3/26—Investigating fluid-tightness of structures by using fluid or vacuum by measuring rate of loss or gain of fluid, e.g. by pressure-responsive devices, by flow detectors
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- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Force Measurement Appropriate To Specific Purposes (AREA)
Abstract
A kind of diesel locomotive unit brake testing stand that the present invention is provided, including testing stand base, test block, installation clamping fixture, control system, measuring system, drive device and protector, also include displacement transducer, radial load sensor and pressure sensor, measuring system includes displacement measurement system, force measuring system and pressure-measuring system, drive device is made up of worm-gear speed reducer and motor, industrial computer and liquid crystal display are provided with control system, effectively improve the accuracy of diesel locomotive unit brake testing stand, reduce the error occurred in process of the test, avoid triggering serious consequence；Diesel locomotive unit brake test platform structure after improvement is simple, facilitates technical staff to be operated, practicality is significantly improved；Protector is set, and security is improved, effectively ensures that experiment is safe and reliable；Drive device provides sufficient power, it is to avoid the consumption plenty of time, it is possible to increase operating efficiency.
Description
Technical field
The present invention relates to a kind of testing stand, more particularly to a kind of diesel locomotive unit brake testing stand belongs in locomotive
Combustion engine technical field.
Background technology
Unit brake be assembled by checking cylinder, casing, slack adjuster, brake head assembling and amplification a few part groups of lever
Into, unit brake be ensure locomotive operation can at a high speed, the important leverage of safe operation, needed in actual production process pair
The performance of unit brake is detected, including the experiment of sensitivity test, brake clearance, test braking force and air-tight test
Deng, and unit brake testing stand is applied to experiment to diesel locomotive unit brake, but current diesel locomotive unit
Also there are some defects in brake tester, in addition it is also necessary to further perfect.
The diesel locomotive unit brake testing stand of prior art, because equipment is more complicated, the skill during use
Art human users are relatively difficult, and the data that existing unit brake testing stand is detected are accurate not enough, it sometimes appear that compared with
Big error, considerable influence is brought to result of the test, influences the accuracy of test, and complex operation reduces unit brake testing stand
Efficiency, therefore technology in terms of diesel locomotive unit brake testing stand will also update.
In general, the diesel locomotive unit brake testing stand of prior art is primarily present following a few point defects：One is
The data that unit brake testing stand is detected are accurate not enough, it sometimes appear that larger error, brings larger to result of the test
Influence, influences the accuracy of test, or even trigger serious consequence；Two be that current device structure is complicated, technical staff's operation
Get up relatively difficult, automaticity is very low, items test needs are accomplished manually, and practicality is not high；Three are the absence of protector,
The use of unit brake testing stand is not safe enough, and safeguard procedures are not enough, it is impossible to ensure the safe and reliable of experiment；Four be drivetrain
The design comparison of system falls behind, and transmission speed ratio is small, it is impossible to self-locking, is short of power, and consumes the substantial amounts of time, reduces operating efficiency；
Five be that monitoring result can not be by signal conversion in liquid crystal screen display, it is impossible to generates experimental report printout, monitoring knot
The output of fruit is not enough quick and precisely.
The content of the invention
In view of the shortcomings of the prior art, a kind of diesel locomotive unit brake testing stand that the present invention is provided, displacement measurement
System, force measuring system and pressure-measuring system cooperate, and effectively improve the accurate of diesel locomotive unit brake testing stand
Degree, reduces the error occurred in process of the test, it is to avoid trigger serious consequence；Diesel locomotive unit brake experiment after improvement
Platform is simple in construction, facilitates technical staff to be operated, and practicality is significantly improved；Protector is provided with, security is improved,
It can effectively ensure that experiment is safe and reliable；Drive device provides sufficient power, it is to avoid the consumption substantial amounts of time, hence it is evident that improve work
Make efficiency；Monitoring result can be by signal conversion in liquid crystal screen display, and can generate experimental report printout, prison
Survey the output of result quick and precisely.
To reach above technique effect, the technical solution adopted in the present invention is as follows：
A kind of diesel locomotive unit brake testing stand, including testing stand base, test block, installation clamping fixture, control system,
Measuring system, drive device and protector, in addition to displacement transducer, radial load sensor and pressure sensor, are surveyed
Amount system includes being provided with pressure sensor on displacement measurement system, force measuring system and pressure-measuring system, test block, drives
Device is made up of worm-gear speed reducer and motor, and industrial computer and liquid crystal display are provided with control system.
A kind of diesel locomotive unit brake testing stand, further, is provided with displacement transducer on displacement measurement system,
The data of displacement transducer collection are changed in liquid crystal screen display by signal.
A kind of diesel locomotive unit brake testing stand, further, on force measuring system is provided with radial loading biography
Sensor, the data of radial load sensor collection are changed in liquid crystal screen display by signal.
A kind of diesel locomotive unit brake testing stand, further, is provided with pressure sensor in pressure-measuring system,
The data of pressure sensor collection are changed in liquid crystal screen display by signal.
A kind of diesel locomotive unit brake testing stand, further, the concave surface of the brake shoe of unit brake and test block
Convex surface be engaged, test block is pressed into contact with being detected by the brake shoe with unit brake.
A kind of diesel locomotive unit brake testing stand, further, protector use stainless steel plate bending and forming, no
It is furnished with peep hole on rust steel plate.
A kind of diesel locomotive unit brake testing stand, further, testing stand base is welded using shaped steel.
A kind of diesel locomotive unit brake testing stand, further, the brake shoe of pressure sensor detection unit brake
Pressure.
A kind of diesel locomotive unit brake testing stand, further, displacement transducer are surveyed by inflation with detection of deflating
The position of test block.
Compared with prior art, the advantage of the invention is that：
1. a kind of diesel locomotive unit brake testing stand that the present invention is provided, including displacement transducer, radial loading
Sensor and pressure sensor, measuring system are included on displacement measurement system, force measuring system and pressure-measuring system, test block
It is provided with to cooperate between pressure sensor, system and effectively improves the accuracy of diesel locomotive unit brake testing stand, subtracts
The error occurred in few process of the test, improves the reliability and accuracy of result of the test, it is to avoid trigger serious consequence.
2. a kind of diesel locomotive unit brake testing stand that the present invention is provided, including testing stand base, test block, installation
Mold, control system, measuring system, drive device and protector, the diesel locomotive unit brake testing stand knot after improvement
Structure is simple, facilitates technical staff to be operated, and automaticity is high, and items test can be automatically performed substantially, and manual intervention is few,
Practicality is significantly improved.
3. a kind of diesel locomotive unit brake testing stand that the present invention is provided, protector is bent into using stainless steel plate
It is furnished with peep hole on shape, stainless steel plate, is provided with protector, security is improved, can effectively ensures that experiment is safe and reliable.
4. a kind of diesel locomotive unit brake testing stand that the present invention is provided, drive device by worm-gear speed reducer and
Motor is constituted, and transmission speed ratio is big, being capable of self-locking, the sufficient power of drive device offer, it is to avoid consumption substantial amounts of time, hence it is evident that carry
High workload efficiency.
5. it is provided with industrial computer and liquid in a kind of diesel locomotive unit brake testing stand that the present invention is provided, control system
Crystalline substance screen, monitoring result can generate experimental report printout by signal conversion in liquid crystal screen display, monitoring result
Output is quick and precisely.
Brief description of the drawings
Fig. 1 is a kind of structural representation for diesel locomotive unit brake testing stand that the present invention is provided.
Fig. 2 is that the present invention removes the top view after protector.
Description of reference numerals：1- testing stand bases, 2- test blocks, 3- installation clamping fixtures, 4- displacement transducers, 5- radial lotuses
Sensor is retransmitted, 6- pressure sensors, 7- drive devices, 8- protectors, 9- industrial computers, 10- liquid crystal displays, 71- worm and gears subtract
Fast machine.
Embodiment
Below in conjunction with the accompanying drawings, a kind of technical scheme of the diesel locomotive unit brake testing stand provided the present invention is carried out
Further description, allows those skilled in the art to be better understood from the present invention and can be practiced.
A kind of diesel locomotive unit brake testing stand provided referring to Fig. 1 and Fig. 2, the present invention, including testing stand base
1st, test block 2, installation clamping fixture 3, control system, measuring system, drive device 7 and protector 8, in addition to displacement transducer 4,
Radial load sensor 5 and pressure sensor 6, measuring system include displacement measurement system, force measuring system and pressure measxurement
Pressure sensor 6 is provided with system, test block 2, drive device 7 is made up of worm-gear speed reducer 71 and motor, control system
Industrial computer 9 and liquid crystal display 10 are provided with system, the diesel locomotive unit brake test platform structure after improvement is simple, facilitates technology
Personnel are operated, and practicality is significantly improved, and are cooperated between system and are effectively improved the examination of diesel locomotive unit brake
The accuracy of platform is tested, the error occurred in process of the test is reduced, it is to avoid triggers serious consequence, drive device 7 provides abundance
Power, transmission speed ratio is big, being capable of self-locking, it is to avoid the consumption substantial amounts of time, hence it is evident that improve operating efficiency.
A kind of diesel locomotive unit brake testing stand provided as a kind of preferred scheme, the present invention, displacement measurement system
Displacement transducer 4 is provided with system, the data that displacement transducer 4 is gathered are changed by signal and shown on liquid crystal display 10, passed through
The real-time monitoring test data of liquid crystal display 10, can generate experimental report printout, the output of monitoring result is quick and precisely.
A kind of diesel locomotive unit brake testing stand provided as a kind of preferred scheme, the present invention, force measuring system
On be provided with radial load sensor 5, the data that radial load sensor 5 is gathered are changed on liquid crystal display 10 by signal
It has been shown that, the data of radial load sensor 5 are monitored by liquid crystal display 10 in real time.
A kind of diesel locomotive unit brake testing stand provided as a kind of preferred scheme, the present invention, pressure measxurement system
Pressure sensor 6 is provided with system, the data that pressure sensor 6 is gathered are changed by signal and shown on liquid crystal display 10, liquid crystal
Screen 10 can show the numerical value of pressure sensor 6 in real time.
A kind of diesel locomotive unit brake testing stand provided as a kind of preferred scheme, the present invention, unit brake
The concave surface of brake shoe be engaged with the convex surface of test block 2, test block 2 is pressed into contact with being examined by the brake shoe with unit brake
Survey.
A kind of a kind of diesel locomotive unit brake testing stand provided as preferred scheme, the present invention, protector 8 is adopted
Use and be furnished with peep hole on stainless steel plate bending and forming, stainless steel plate, be provided with protector 8, security is improved, can be effectively true
Protect experiment safe and reliable.
A kind of diesel locomotive unit brake testing stand provided as a kind of preferred scheme, the present invention, testing stand base 1
It is welded using shaped steel.
A kind of diesel locomotive unit brake testing stand provided as a kind of preferred scheme, the present invention, pressure sensor 6
The brake shoe pressure of detection unit brake.
A kind of diesel locomotive unit brake testing stand provided as a kind of preferred scheme, the present invention, displacement transducer 4
By inflating the position with detection test block 2 of deflating.
The operation principle that the present invention is provided：
The concave surface of brake shoe is engaged the experiment below completing with the convex surface of the test block 2 of experimental rig on unit brake.
1st, test braking force：Checking cylinder assembling is made up of checking cylinder, piston, leather cup, after compressed air is filled with into cylinder,
Piston will produce motion, promote lever to move ahead, amplified to act on brake head, and then form brake shoe pressure.Brake shoe during test
It is pressed into contact with test block 2, pressure sensor 6 is provided with test block 2, pressure sensor 6 can detect brake shoe pressure.
2nd, brake clearance is tested：Brake shoe is pressed into contact with test block 2 during test, keeps pressure constant in test process, examination
Equipment has displacement transducer 4 on experiment device, and displacement transducer 4 can analyze detection unit brake in inflation and deflation course
The position of test block 2.
3. air-tight test：Inflated respectively into checking cylinder or shutoff cylinder, the test checking cylinder of pressure sensor 6 or shutoff cylinder
Interior pressure.
The course of work that the present invention is provided：
1. sensitivity test:50KPa pressure airs are poured to checking cylinder, 3 experiments are carried out continuously, action well can determine that
Sensitivity is qualified.
2. brake slack adjuster is tested：Under the normal relieved state of normal temperature, brake head is adjusted to most short position, in braking
Reference point is selected on device, it is measured to Zha Tuo center of arc point apart from L, checking cylinder is inflated repeatedly, is vented, when brake head is pushed away
Output is not in increase, under relieved state, difference apart from La, L and La of the witness mark to brake head center of arc point
As total adjustment amount, total adjustment amount L-La >=110mm is qualified.
3. test braking force:
(1) checking cylinder test braking force：When brake shoe is in normal clearance with tread, 350KPa compressions are filled with to checking cylinder empty
Gas, measures brake shoe power output, should >=34.2KN ± 5%, when being filled with 450KPa compressed airs to checking cylinder, measure brake shoe power output
Should >=44KN ± 5% is qualified.
(2) spring braking device test braking force：600KPa compressed airs are filled with to Parking brake cylinder, are then emptied, it is real
Apply stopping brake, measure spring braking power, spring braking power should >=31.5KN ± 5% is qualified.
4. air-tight test：
(1) low-pressure air leakage test：Under normal temperature condition, 100KPa pressure is filled with into checking cylinder or shutoff cylinder respectively
Contracting air, pressurize 3 minutes, it is qualified that amount of leakage, which is not more than 2KPa,.
(2) high pressure air-tight test：Under normal temperature condition, 430-465KPa compressed airs are filled with into checking cylinder respectively,
600-650KPa compressed airs, pressurize 3 minutes are filled with spring stop cylinder, it is qualified that amount of leakage, which is not more than 2KPa,.
The basic principles, principal features and advantages of the present invention have been shown and described above.The technical staff of the industry should
Understand, the present invention is not limited to the above embodiments, the original for simply illustrating the present invention described in above-described embodiment and specification
Reason, without departing from the spirit and scope of the present invention, various changes and modifications of the present invention are possible, these changes and improvements
It all fall within the protetion scope of the claimed invention.The claimed scope of the invention is by appended claims and its Xiao Wu circle
It is fixed.
Claims (9)
1. a kind of diesel locomotive unit brake testing stand, it is characterised in that：Including testing stand base (1), test block (2), peace
Fill mold (3), control system, measuring system, drive device (7) and protector (8), in addition to displacement transducer (4), spoke
Formula load sensor (5) and pressure sensor (6), the measuring system include displacement measurement system, force measuring system and pressure
Pressure sensor (6) is provided with measuring system, the test block (2), the drive device (7) is by worm-gear speed reducer
(71) constituted with motor, industrial computer (9) and liquid crystal display (10) are provided with the control system.
2. a kind of diesel locomotive unit brake testing stand according to claim 1, it is characterised in that：Institute's displacement measurement
Institute's displacement sensors (4) are provided with system, the data of institute's displacement sensors (4) collection are changed in liquid crystal display by signal
(10) shown on.
3. a kind of diesel locomotive unit brake testing stand according to claim 1, it is characterised in that：The power measurement system
The radial load sensor (5) is provided with system, the data of radial load sensor (5) collection are turned by signal
Change and shown on liquid crystal display (10).
4. a kind of diesel locomotive unit brake testing stand according to claim 1, it is characterised in that：The pressure measxurement
The pressure sensor (6) is provided with system, the data of pressure sensor (6) collection are changed in liquid crystal display by signal
(10) shown on.
5. a kind of diesel locomotive unit brake testing stand according to claim 1, it is characterised in that：Unit brake
The concave surface of brake shoe is engaged with the convex surface of the test block (2), and the test block (2) with the brake shoe of unit brake by compressing
Contact is detected.
6. a kind of diesel locomotive unit brake testing stand according to claim 1, it is characterised in that：The protector
(8) use and be furnished with peep hole on stainless steel plate bending and forming, the stainless steel plate.
7. a kind of diesel locomotive unit brake testing stand according to claim 1, it is characterised in that：The testing stand bottom
Seat (1) is welded using shaped steel.
8. a kind of diesel locomotive unit brake testing stand according to claim 1, it is characterised in that：The pressure sensing
The brake shoe pressure of device (6) detection unit brake.
9. a kind of diesel locomotive unit brake testing stand according to claim 1, it is characterised in that：The displacement sensing
Device (4) detects the position of the test block (2) by inflating with deflating.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710537697.XA CN107192547A (en) | 2017-07-04 | 2017-07-04 | A kind of diesel locomotive unit brake testing stand |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710537697.XA CN107192547A (en) | 2017-07-04 | 2017-07-04 | A kind of diesel locomotive unit brake testing stand |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN107192547A true CN107192547A (en) | 2017-09-22 |
Family
ID=59880748
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201710537697.XA Pending CN107192547A (en) | 2017-07-04 | 2017-07-04 | A kind of diesel locomotive unit brake testing stand |
Country Status (1)
| Country | Link |
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| CN (1) | CN107192547A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107976310A (en) * | 2017-11-21 | 2018-05-01 | 中车株洲电力机车有限公司 | A kind of brake test tool |
| CN110487569A (en) * | 2019-08-26 | 2019-11-22 | 中国铁道科学研究院集团有限公司 | The full-automatic testing device and method of tread braking unit |
| CN110514426A (en) * | 2019-09-18 | 2019-11-29 | 华南理工大学 | A kind of performance testing device of mechanical electronic hydraulic composite braking system |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN201637573U (en) * | 2009-12-24 | 2010-11-17 | 重庆和平自动化工程有限公司 | On-line automatic high-speed testing system for general-purpose engine |
| CN203011706U (en) * | 2012-12-17 | 2013-06-19 | 常州科兴铁路装备有限公司 | Multi-variety microcomputer control unit brake test bench |
| JP2013140125A (en) * | 2012-01-06 | 2013-07-18 | Ntn Corp | Bearing device for wheel with sensor and vehicle control device using sensor output thereof |
| CN104833528A (en) * | 2015-05-15 | 2015-08-12 | 长春速建新技术开发有限公司 | Oil cylinder lifting type lift brake test platform |
| CN105806611A (en) * | 2016-06-08 | 2016-07-27 | 中车株洲电力机车有限公司 | Brake fatigue test system |
| CN206114291U (en) * | 2016-09-07 | 2017-04-19 | 韶关比亚迪实业有限公司 | Transaxle break -in testing arrangement |
| CN207095832U (en) * | 2017-07-04 | 2018-03-13 | 襄阳国铁机电股份有限公司 | A kind of diesel locomotive unit brake testing stand |
-
2017
- 2017-07-04 CN CN201710537697.XA patent/CN107192547A/en active Pending
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN201637573U (en) * | 2009-12-24 | 2010-11-17 | 重庆和平自动化工程有限公司 | On-line automatic high-speed testing system for general-purpose engine |
| JP2013140125A (en) * | 2012-01-06 | 2013-07-18 | Ntn Corp | Bearing device for wheel with sensor and vehicle control device using sensor output thereof |
| CN203011706U (en) * | 2012-12-17 | 2013-06-19 | 常州科兴铁路装备有限公司 | Multi-variety microcomputer control unit brake test bench |
| CN104833528A (en) * | 2015-05-15 | 2015-08-12 | 长春速建新技术开发有限公司 | Oil cylinder lifting type lift brake test platform |
| CN105806611A (en) * | 2016-06-08 | 2016-07-27 | 中车株洲电力机车有限公司 | Brake fatigue test system |
| CN206114291U (en) * | 2016-09-07 | 2017-04-19 | 韶关比亚迪实业有限公司 | Transaxle break -in testing arrangement |
| CN207095832U (en) * | 2017-07-04 | 2018-03-13 | 襄阳国铁机电股份有限公司 | A kind of diesel locomotive unit brake testing stand |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107976310A (en) * | 2017-11-21 | 2018-05-01 | 中车株洲电力机车有限公司 | A kind of brake test tool |
| CN107976310B (en) * | 2017-11-21 | 2021-02-05 | 中车株洲电力机车有限公司 | Brake test tool |
| CN110487569A (en) * | 2019-08-26 | 2019-11-22 | 中国铁道科学研究院集团有限公司 | The full-automatic testing device and method of tread braking unit |
| CN110514426A (en) * | 2019-09-18 | 2019-11-29 | 华南理工大学 | A kind of performance testing device of mechanical electronic hydraulic composite braking system |
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