CN103837341A - Method for obtaining circumferential load distribution of friction plate tooth part through variable-contact-rigidity testing - Google Patents
Method for obtaining circumferential load distribution of friction plate tooth part through variable-contact-rigidity testing Download PDFInfo
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- CN103837341A CN103837341A CN201410035136.6A CN201410035136A CN103837341A CN 103837341 A CN103837341 A CN 103837341A CN 201410035136 A CN201410035136 A CN 201410035136A CN 103837341 A CN103837341 A CN 103837341A
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Abstract
The invention belongs to the technical field of testing simulation, and provides a method for obtaining circumferential load distribution of a friction plate tooth part through variable-contact-rigidity testing. The method aims at carrying out testing on static stress on the friction element tooth part, accordingly achieving mutual verification of two distribution rule testing results, and providing theoretical supports for dynamic strength simulation and design of a friction element. According to the method, the mass data synchronous collecting problem difficult to solve can be solved, middle testing links and a data processing link are omitted, the distribution characteristics of circumferential loads of the friction plate tooth part can be directly obtained through a variable-contact-rigidity curve obtained through the testing, and the accuracy of the testing results is improved; the testing method is simple, practical and high in testing result accuracy.
Description
Technical field
The invention belongs to test simulation technical field, be specifically related to a kind of method of obtaining the circumferential load distribution of friction disc tooth portion by becoming contact stiffness test.
Background technology
Kinematic train is as the important component part of special vehicle, and its performance directly affects maneuverability (as braking, trafficability characteristic, acceleration), reliability and the serviceable life of vehicle, and the inefficacy of kinematic train will directly cause special vehicle to be lost and use.
Clutch friction pair is one of important basic components of kinematic train.In Practical Project, when friction pair power transmission, often there is spot corrosion, the crackle equivalent damage that even ruptures in engaging tooth portion, there is the reason of above-mentioned damage in order to probe into friction pair tooth portion engaged transmission, need to study circumferential load distribution characteristics and the Changing Pattern thereof of friction pair tooth portion intensity in engaged transmission process.Obtain above characteristic parameter, must carry out the circumferential load distribution experimental test of friction pair tooth portion.And if by the direct method of testing (as pasted 108 foil gauges on the whole teeth of 522 friction disc) of the circumferential load of tooth portion, not only be subject to testing equipment condition and limit (cannot find multichannel collecting device like this), and it is not identical with the contact force of generation in the position of each tooth engagement, the load obtaining also cannot fully reflect tooth portion actual engagement loading procedure, can not obtain stress distribution characteristic curve accurately.Therefore, need a kind of other testing method that can obtain by certain measuring technology means the circumferential load distribution characteristic of friction disc tooth portion.
Summary of the invention
(1) technical matters that will solve
The technical problem to be solved in the present invention is to provide a kind of testing method that obtains the circumferential load distribution of friction disc tooth portion by becoming contact stiffness test, for providing theoretical, the resistance to vibration simulation and design of friction element supports, this test simultaneously also can be carried out the test of friction element tooth portion static stress, thereby realizes the mutual checking of two kinds of regularity of distribution test results.
(2) technical scheme
For solving the problems of the technologies described above, the invention provides a kind of method of obtaining the circumferential load distribution of friction disc tooth portion by becoming contact stiffness test, it is characterized in that: the method comprises the steps:
Wherein, described groove pressing plate is radially uniformly distributed the strain acquirement data of 3 directions in fluting place.
Wherein, each direction of described 3 directions is made up of 6 strain rosette sensors.
Wherein, described strain rosette direction be friction disc tooth root place circumferentially and flank engagement place along normal force direction.
Wherein, describedly convert change contact micrometric displacement signal to mesh stiffness data, and obtain the method for circumferential load distribution characteristics, comprise the steps:
Wherein, described depth of groove is by 1/3 of specimen thickness.
Wherein, described specified pressure is 10MPa.
(3) beneficial effect
Compared with prior art, the present invention possesses following beneficial effect:
1, the test method of obtaining the circumferential load distribution characteristics of friction disc tooth portion by becoming contact stiffness test provided by the invention, not only can avoid insoluble synchronous acquisition mass data problem, semipilot link and data processing link are reduced, and the change contact stiffness curve that can obtain by experimental test, directly obtain the distribution characteristics of the circumferential load of friction disc tooth portion, improved the precision of experimental test result;
2, testing method provided by the invention is simple, practical, test result precision is high, the result obtaining by the present invention, can reflect comprehensive actuator speed change friction pair characteristic in actual use completely, and for further deeply to probe into the various performances (as resistance to vibration) in friction disc tooth portion engagement process, provide good method to use for reference.
Brief description of the drawings
Fig. 1 is the test platform structure arrangenent diagram of setting up according to the present invention;
Fig. 2 is for becoming contact stiffness experimental test result figure.
Embodiment
For making object of the present invention, content and advantage clearer, below in conjunction with drawings and Examples, the specific embodiment of the present invention is described in further detail.
Clutch friction pair is one of important basic components of kinematic train.In Practical Project, when friction pair power transmission, often there is spot corrosion, the crackle equivalent damage that even ruptures in engaging tooth portion.There is the reason of above-mentioned damage in order to probe into friction pair tooth portion engaged transmission, need to study circumferential load distribution characteristics and the Changing Pattern thereof of friction pair tooth portion intensity in engaged transmission process.Obtain above characteristic parameter, must carry out corresponding experimental test.
Ultimate value speed change friction pair power transmission being required according to gearing, is set as testing maximal value by this torque value, by the table apparatus of design, at the power intake of testing table, will be set as fixed step size increment by test piece torque loaded value.Record high sensitivity micrometric displacement changing value in loading procedure and the variation relation of loaded value, and be entered in the mesh stiffness program of finishing, by being related to conversion formula, drawing the variation relation of engaging tooth number percent number and mesh stiffness, and then obtain circumferential load distribution.
As shown in Figure 1, testing method provided by the present invention is realized by becoming contact stiffness experimental test platform, and this experiment test platform is mainly made up of testing table clutch end 1, torque sensor 2, spline joint dish 3, spline joint cylinder 4, outer end clamp plate 5, large radius arrowband friction disc 6, groove pressing plate 7, web joint 8, support 9, butterfly spring 10, interior hub 11, sensor stand 12, high sensitivity capacitive displacement transducer 13, output terminal spline joint dish 14 and connecting cylinder supporting seat 15.
The method of obtaining the circumferential load distribution of friction disc tooth portion by becoming contact stiffness test provided by the invention, the method comprises the steps:
Wherein, described groove pressing plate is radially uniformly distributed the strain acquirement data of 3 directions in fluting place.
Wherein, each direction of described 3 directions is made up of 6 strain rosette sensors.
As shown in Figure 1, spline joint cylinder 4 is connected with interior hub 11 by output terminal spline joint dish 14.Test unit is the circumferential load distribution of friction disc under test float support, but due to interior hub 11 and output terminal spline joint dish 14 own wts larger, can produce larger downward gravity, the lower end tooth and the friction disc 6 engaging tooths generations that make interior hub 11 are preloaded acting force by this gravity.Therefore, spline joint cylinder 4 bottoms near terminal pad 14 near, the semi-circular bracket of a supporting role is installed, to keep interior hub and friction disc in the time not applying outer opplied moment, engagement under float support condition completely, eliminate the influence of prestress to test result completely, improved the accuracy of test.
Wherein, describedly convert change contact micrometric displacement signal to mesh stiffness data, and obtain the method for circumferential load distribution characteristics, comprise the steps:
As shown in Figure 2, under torque load effect outside, the twist process of distortion of friction disc engaging tooth portion is divided into two parts: eliminate interstitial area and elastic deformation area.Moment of torsion load the starting stage, owing to having gap between hub in float support 11 and friction disc 6 engaging tooth portions, between two articles tooth portion gap diminish gradually until completely eliminate, now displacement deformation amount in elimination interstitial area within the scope of, the circumferential load of friction disc is zero.Along with the increase of torque load, engaging tooth contacts and starts to occur elastic deformation, but due to the impact of the various factorss such as gravity, processing, installation, when interior hub 11 is initial with friction disc 6, only part tooth comes in contact and elastic deformation, therefore rigidity shows as low value, be that friction disc only has minority tooth in engagement, program converts as calculated, accounts for 2% left and right of whole numbers of teeth.Along with the continuation of outer action torque increases, interior hub 11 increases gradually with friction disc 6 total number of teeth in engagement, and tooth portion torsional rigidity is in Fast growth phase.By test, mesh stiffness overall process has 3 times and significantly changes.In this change procedure, engaging tooth elastic deformation amount increase gradually, and total number of teeth in engagement increases gradually, and therefore rigidity be phase step type and increase.When moment of torsion continues to increase, when interior hub 11 approximately reaches 97% left and right of whole numbers of teeth with friction disc 6 total number of teeth in engagement, friction disc tooth portion torsional rigidity reaches maximal value, and remains unchanged.
Principle of the present invention:
Under the load of clutch end 1, interstitial area and two processes of elastic deformation area can be eliminated by friction disc engaging tooth portion.Moment of torsion load the starting stage, owing to having gap between hub in float support 11 and friction disc 6 engaging tooth portions, between two articles tooth portion gap diminish gradually until completely eliminate, now displacement deformation amount in elimination interstitial area within the scope of, the circumferential load of friction disc is zero.Along with the increase of torque load, engaging tooth contacts and starts to occur elastic deformation, but due to the impact of the various factorss such as gravity, processing, installation, when interior hub 11 is initial with friction disc 6, only part tooth comes in contact and elastic deformation, therefore rigidity shows as low value, and friction disc only has minority tooth in engagement.Along with the action torque of clutch end 1 continues to increase, interior hub 11 increases gradually with friction disc 6 total number of teeth in engagement, and engaging tooth elastic deformation amount increase gradually, and tooth portion torsional rigidity will be phase step type build phase.When the action torque of clutch end 1 continues to increase, interior hub 11 will reach full-depth tooth with friction disc 6 total number of teeth in engagement and engage or approach the state that full-depth tooth engages, and friction disc tooth portion torsional rigidity reaches maximal value.In the time that action torque continues to increase, total number of teeth in engagement no longer changes, and in friction disc tooth portion regime of elastic deformation, friction disc tooth portion deflection no longer changes, and torsional rigidity remains unchanged substantially, and now the circumferential load of friction disc tooth portion is distributed as full-depth tooth engagement.
According to the present invention, adopt the method for multiple spot flank static stress test and collection in friction disc tooth portion, realize by the comparative analysis of the circumferential load distribution characteristics of test specimen situation, obtain the accuracy of the circumferential load distribution results of friction pair tooth portion to be verified change contact stiffness.
The above is only the preferred embodiment of the present invention; it should be pointed out that for those skilled in the art, do not departing under the prerequisite of the technology of the present invention principle; can also make some improvement and distortion, these improvement and distortion also should be considered as protection scope of the present invention.
Claims (7)
1. obtain by becoming contact stiffness test the method that the circumferential load of friction disc tooth portion distributes, it is characterized in that: the method comprises the steps:
Step 1, the array mode of utilizing multi-disc butterfly spring to be superimposed as one group is carried out the pressurization of Control experiment device, makes the pressure between pressing plate and friction disc keep specified pressure;
Step 2, set the degree of depth of groove pressing plate according to friction factor, make groove pressing plate should play friction disc positioning action, can meet again the axle pressure between outer end clamp plate and groove pressing plate, make friction disc there is enough friction force, also will take into account simultaneously and keep friction disc frictional layer frictional behaviour;
Step 3, according to friction pair tooth portion engaging stress direction, is arranged on interior hub engaging tooth portion side by the test position of high sensitivity displacement transducer, and direction is normal orientation;
Step 4, carries out mesh stiffness data-switching to the change contact displacement micro-signal measuring, and obtains circumferential load distribution characteristics.
2. according to claim 1ly obtain by becoming contact stiffness test the method that the circumferential load of friction disc tooth portion distributes, it is characterized in that: described groove pressing plate radially fluting place is uniformly distributed the strain acquirement data of 3 directions.
3. the method for obtaining the circumferential load distribution of friction disc tooth portion by becoming contact stiffness test according to claim 2, is characterized in that: each direction of described 3 directions is made up of 6 strain rosette sensors.
4. according to claim 3ly obtain by becoming contact stiffness test the method that the circumferential load of friction disc tooth portion distributes, it is characterized in that: described strain rosette direction be friction disc tooth root place circumferentially and flank engagement place along normal force direction.
5. the method for obtaining the circumferential load distribution of friction disc tooth portion by becoming contact stiffness test according to claim 1, it is characterized in that: describedly convert change contact micrometric displacement signal to mesh stiffness data, and obtain the method for circumferential load distribution characteristics, comprise the steps:
Step 1, the program that the information that becomes contact micro-displacement sensor test is write through data collecting instrument and computing machine, converts its corresponding tooth portion mesh stiffness data to;
Step 2, calculates the mesh stiffness of monodentate according to theory, derive the real-time total number of teeth in engagement of friction pair and in full-depth tooth engagement shared number percent number, and then obtain the circumferential load distribution characteristics of tooth portion.
6. the method for obtaining the circumferential load distribution of friction disc tooth portion by becoming contact stiffness test according to claim 1, is characterized in that: described depth of groove is by 1/3 of specimen thickness.
7. the method for obtaining the circumferential load distribution of friction disc tooth portion by becoming contact stiffness test according to claim 1, is characterized in that: described specified pressure is 10MPa.
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Cited By (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104634676A (en) * | 2015-02-13 | 2015-05-20 | 中国北方车辆研究所 | Method for controlling dynamic test load of friction plate and system for realizing method |
| CN104931259A (en) * | 2015-06-29 | 2015-09-23 | 中国北方车辆研究所 | Method for testing thermal-elastic coupled vibration characteristics in friction and sliding process of variable speed friction plate |
| CN107677438A (en) * | 2017-10-12 | 2018-02-09 | 电子科技大学 | Epicyclic gearbox sun gear gradual change spot corrosion time-variant mesh stiffness analysis method |
| CN110567708A (en) * | 2019-08-14 | 2019-12-13 | 中国北方车辆研究所 | friction plate vibration fatigue test device |
| CN110567706A (en) * | 2019-08-14 | 2019-12-13 | 中国北方车辆研究所 | Friction plate impact plastic deformation test system |
| CN110567707A (en) * | 2019-08-14 | 2019-12-13 | 中国北方车辆研究所 | Friction plate impact plastic deformation test device |
| CN110567709A (en) * | 2019-08-14 | 2019-12-13 | 中国北方车辆研究所 | Equivalent constant-load simulation loading test system for friction plate tooth part |
| CN110967185A (en) * | 2018-09-28 | 2020-04-07 | 中国航发商用航空发动机有限责任公司 | Rotor bearing radial load measuring method and device and aircraft engine |
| CN111458236A (en) * | 2020-04-01 | 2020-07-28 | 中国北方车辆研究所 | Friction plate actual condition thermal fatigue load simulation test device |
| CN116625926A (en) * | 2023-04-17 | 2023-08-22 | 中国北方车辆研究所 | Friction performance testing device for inertia load friction element |
| CN116659851A (en) * | 2023-04-18 | 2023-08-29 | 中国北方车辆研究所 | Torsion rigidity test system for floating support friction plate |
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Cited By (18)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104634676A (en) * | 2015-02-13 | 2015-05-20 | 中国北方车辆研究所 | Method for controlling dynamic test load of friction plate and system for realizing method |
| CN104634676B (en) * | 2015-02-13 | 2017-09-01 | 中国北方车辆研究所 | A kind of system for controlling the method for friction plate dynamic test load and realizing this method |
| CN104931259A (en) * | 2015-06-29 | 2015-09-23 | 中国北方车辆研究所 | Method for testing thermal-elastic coupled vibration characteristics in friction and sliding process of variable speed friction plate |
| CN104931259B (en) * | 2015-06-29 | 2017-06-09 | 中国北方车辆研究所 | A kind of speed change friction plate rubs and slips over journey Thermoelastic Vibration characteristic test method |
| CN107677438A (en) * | 2017-10-12 | 2018-02-09 | 电子科技大学 | Epicyclic gearbox sun gear gradual change spot corrosion time-variant mesh stiffness analysis method |
| CN110967185B (en) * | 2018-09-28 | 2022-02-22 | 中国航发商用航空发动机有限责任公司 | Rotor bearing radial load measuring method and device and aircraft engine |
| CN110967185A (en) * | 2018-09-28 | 2020-04-07 | 中国航发商用航空发动机有限责任公司 | Rotor bearing radial load measuring method and device and aircraft engine |
| CN110567706A (en) * | 2019-08-14 | 2019-12-13 | 中国北方车辆研究所 | Friction plate impact plastic deformation test system |
| CN110567707A (en) * | 2019-08-14 | 2019-12-13 | 中国北方车辆研究所 | Friction plate impact plastic deformation test device |
| CN110567709A (en) * | 2019-08-14 | 2019-12-13 | 中国北方车辆研究所 | Equivalent constant-load simulation loading test system for friction plate tooth part |
| CN110567708B (en) * | 2019-08-14 | 2021-05-14 | 中国北方车辆研究所 | Friction plate vibration fatigue test device |
| CN110567708A (en) * | 2019-08-14 | 2019-12-13 | 中国北方车辆研究所 | friction plate vibration fatigue test device |
| CN111458236A (en) * | 2020-04-01 | 2020-07-28 | 中国北方车辆研究所 | Friction plate actual condition thermal fatigue load simulation test device |
| CN111458236B (en) * | 2020-04-01 | 2022-10-28 | 中国北方车辆研究所 | Friction plate actual condition thermal fatigue load simulation test device |
| CN116625926A (en) * | 2023-04-17 | 2023-08-22 | 中国北方车辆研究所 | Friction performance testing device for inertia load friction element |
| CN116625926B (en) * | 2023-04-17 | 2024-03-26 | 中国北方车辆研究所 | Friction performance testing device for inertia load friction element |
| CN116659851A (en) * | 2023-04-18 | 2023-08-29 | 中国北方车辆研究所 | Torsion rigidity test system for floating support friction plate |
| CN116659851B (en) * | 2023-04-18 | 2024-03-15 | 中国北方车辆研究所 | Torsion rigidity test system for floating support friction plate |
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