CN204783954U - High frequency is pneumatic cylinder durability test device for nonoculture based on parallel internet technology - Google Patents
High frequency is pneumatic cylinder durability test device for nonoculture based on parallel internet technology Download PDFInfo
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- CN204783954U CN204783954U CN201520375030.0U CN201520375030U CN204783954U CN 204783954 U CN204783954 U CN 204783954U CN 201520375030 U CN201520375030 U CN 201520375030U CN 204783954 U CN204783954 U CN 204783954U
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Abstract
The utility model discloses a high frequency is pneumatic cylinder durability test device for nonoculture based on parallel internet technology, the device include for nonoculture measuring device such as pneumatic cylinder, choke valve and various pressure, flow, displacement of high frequency action that motor, hydraulic pump, two cross proportion switching -over valves, proportion overflow valve, energy storage ware module, 6 quilts surveyed. Provide the testing system of a plurality of pneumatic cylinders of while testing in the process of the test through parallel internet technology, two cross proportion switching -over valves carry out high -frequency reciprocating motion durability test (the highest reciprocating motion frequency can reach 30Hz) through the high -frequency switching -over to the pneumatic cylinder, and pneumatic cylinder durability performance parameter is by automatic acquisition and analytical calculation in the process of the test. This test device can realize at least durability test to 6 high frequencies actions pneumatic cylinder for the nonoculture simultaneously, has saved test time, has practiced thrift the energy, has simplified test device, has reduced experimentation cost.
Description
Technical field
The utility model relates to a kind of hydraulic cylinder durability testing apparatus, particularly relates to a kind of high frequency single-action hydraulic cylinder durability test device based on parallel power-saving technology.
Background technique
Hydraulic energy is changed into mechanical energy, does the hydraulic actuator of straight reciprocating motion (or oscillating motion) by oil hydraulic cylinder, is substantially made up of cylinder barrel and cylinder cap, piston and piston rod, seal arrangement, damping device and venting gas appliance.Its structure is simple, reliable operation.When realizing to-and-fro motion with it, can speed reducer be removed from, and there is no drive gap, stable movement, therefore be used widely in the hydraulic system of various machinery.Oil hydraulic cylinder is as the critical elements of Hydraulic Power Transmission System, and its life level directly has influence on durability and the Security of whole hydraulic system, for guaranteeing that oil hydraulic cylinder normally runs and finds its weak link, needs to carry out endurance test.The general test loop with reference to machinery industry standard GB/T15622-2005, current domestic hydraulic cylinder durability test loop, this kind of scheme can only be tested for Normal hydraulic cylinder, cannot meet the test requirements document of high frequency direction changing ratio oil hydraulic cylinder, simultaneously few, the consuming time length of single test sample size, cost are high.
Model utility content
Technical problem to be solved in the utility model provides a kind of special testing apparatus carrying out the test of high-frequent reciprocating exercise endurance for high frequency mo single-action hydraulic cylinder, and make this testing apparatus can test the endurance test of multiple oil hydraulic cylinder by parallel power-saving technology simultaneously, save test period, simplify testing apparatus, reduce experimentation cost simultaneously.
The utility model solves the problems of the technologies described above adopted technological scheme: a kind of high frequency single-action hydraulic cylinder durability test device based on parallel power-saving technology, it is characterized in that: comprise the oil hydraulic pump rotated by driven by motor, oil hydraulic pump in-line connects fuel tank by stop valve, vent line connects one-way valve, one-way valve rear oil duct is divided into two branch roads, one branch road is through proportional pressure control valve oil sump tank, and another branch road connects force feed filter, force feed filter the other end oil circuit is divided into two branch roads, and a branch road connects the oil-feed interface of energy storage module, and the draining road of energy storage module connects fuel tank, and another branch road connects the P mouth of two four-way proportional reversing valves, the T mouth hydraulic circuit of two four-way proportional reversing valves connects fuel tank, A mouth multiple detection unit in parallel simultaneously of two four-way proportional reversing valves, B mouth multiple detection unit in parallel simultaneously of two four-way proportional reversing valves, each detection unit comprises stop valve, tested high frequency mo single-action hydraulic cylinder, graduated cylinder, displacement transducer, pressure sensor and spring loaded mechanism, hydraulic circuit is drawn from the A mouth of two four-way proportional reversing valves and B mouth, respectively through the oil inlet and outlet of stop valve multiple tested high frequency mo single-action hydraulic cylinder in parallel, the drain tap of tested high frequency mo single-action hydraulic cylinder connects graduated cylinder after pipeline is drawn, described pressure sensor one end connects the hydraulic rod end of tested high frequency mo single-action hydraulic cylinder, the other end linking springs deceleration loading device, change in time to detect hydraulic rod ouput force, displacement transducer is arranged on hydraulic rod to detect hydraulic rod displacement over time, one first pressure transducer is had to be arranged on proportional pressure control valve in-line with detection system pressure, there is one second pressure transducer to be arranged on the A mouth place of two four-way proportional reversing valves, change in order to the pressure detecting tested high frequency mo single-action hydraulic cylinder in parallel with A mouth, there is one the 3rd pressure transducer to be arranged on the B mouth place of two four-way proportional reversing valves, change in order to the pressure detecting tested high frequency mo single-action hydraulic cylinder in parallel with B mouth.
Above-mentioned fuel tank internal is provided with the heater to fluid heating, and in order to the temperature transducer to detect oil liquid temperature; The T mouth hydraulic circuit of two four-way proportional reversing valves connects fuel tank successively after throttle valve, radiator.Throttle valve is arranged on system oil return road, for tested high frequency mo single-action hydraulic cylinder provides backhaul back pressure, makes tested high frequency mo single-action hydraulic cylinder easy motion; Radiator and heater devices, make system oil temperature remain stable.
A mouth three detection units in parallel simultaneously of above-mentioned two four-way proportional reversing valves, are respectively the first detection unit, the second detection unit, the 3rd detection unit; B mouth three detection units in parallel simultaneously of two four-way proportional reversing valves, are respectively the 4th detection unit, the 5th detection unit, the 6th detection unit.A mouth and each three detection units in parallel of B mouth, its working efficiency and testing precision reach one and merge preferably.
Above-mentioned pressure sensor is cylindrical shape.
Compared with prior art, the utility model has the advantage of:
1, the high-frequency reciprocating exercise endurance test of 30Hz can be up to oil hydraulic cylinder, solve the problem that existing testing installation can not meet reciprocating frequency requirement.
2, whole testing apparatus is reasonable in design: under the commutation action of two four-way proportional reversing valves, and multiple oil hydraulic cylinder is divided into two groups alternately to complete the action of stretching out, retracting by hydraulic circuit; Energy storage module plays a part to absorb impacts, and makes system pressure remain stable; Force feed metre filter precision is high, ensures that proportional reversing valve and multiple tested liquid cylinder pressure are to the requirement of high cleanliness fluid; Throttle valve is arranged on system oil return road, for multiple oil hydraulic cylinder provides backhaul back pressure, makes oil hydraulic cylinder easy motion; Radiator and heater devices, make system oil temperature remain stable.
3, the parallel power-saving technology of application in endurance test, namely single test can carry out endurance test to multiple (6) high frequency mo single-action hydraulic cylinder simultaneously, adds test sample number, simplify testing apparatus, test efficiency is high, consuming time short, energy saving, reduces experimentation cost.
4, high frequency mo single-action hydraulic cylinder endurance test major parameter all uses sensor Real-Time Monitoring, can make accurate judgement, and make accurate analysis to failure cause to the current state of detected element.
5, testing apparatus adopts electrical control, and automaticity is high, easy and simple to handle.
Accompanying drawing explanation
Fig. 1 is the structural representation of the utility model embodiment.
In Fig. 1: 1, energy storage module; 2, two four-way proportional reversing valves; 3, pressure transducer; 4, pressure transducer; 5, stop valve; 6, tested high frequency mo single-action hydraulic cylinder; 7, graduated cylinder, 8, displacement transducer; 9, pressure sensor; 10, spring loaded mechanism; 11, the first detection unit; 12, the second detection unit; 13, the 3rd detection unit; 14, the 4th detection unit; 15, the 5th detection unit; 16, the 6th detection unit; 17, heater; 18, temperature transducer; 19, throttle valve; 20, cooler; 21, one-way valve; 22, stop valve; 23, oil hydraulic pump; 24, motor; 25, proportional pressure control valve; 26, pressure transducer; 27, force feed filter; 28, fuel tank.
Embodiment
Below in conjunction with accompanying drawing, embodiment is described in further detail the utility model.
As shown in Figure 1, be a preferred embodiment of the utility model testing apparatus.
Based on a high frequency single-action hydraulic cylinder durability test device for parallel power-saving technology, comprise
Driven the oil hydraulic pump 23 of rotation by motor 24, oil hydraulic pump 23 in-line connects fuel tank 28 by stop valve, and fuel tank 28 inside is provided with the heater 17 to fluid heating, and in order to the temperature transducer 18 to detect oil liquid temperature.Oil hydraulic pump 23 vent line connects one-way valve 21, and one-way valve 21 rear oil duct is divided into two branch roads, and a branch road is through proportional pressure control valve 25 oil sump tank 28, and another branch road connects force feed filter 27.
Force feed filter 27 the other end oil circuit is divided into two branch roads, and a branch road connects the oil-feed interface of energy storage module 1, and the draining road of energy storage module 1 connects fuel tank 28, and another branch road connects the P mouth of two four-way proportional reversing valves 2.
The T mouth hydraulic circuit of two four-way proportional reversing valves 2 connects fuel tank 28 successively after throttle valve 19, radiator 20, A mouth three detection units in parallel simultaneously of two four-way proportional reversing valves 2, are respectively the first detection unit 11, second detection unit 12, the 3rd detection unit 13; B mouth three detection units in parallel simultaneously of two four-way proportional reversing valves 2, are respectively the 4th detection unit 14, the 5th detection unit 15, the 6th detection unit 16.
Each detection unit comprises stop valve 5, tested high frequency mo single-action hydraulic cylinder 6, graduated cylinder 7, displacement transducer 8, pressure sensor 9 and spring loaded mechanism 10, hydraulic circuit is drawn from the A mouth of two four-way proportional reversing valves 2 and B mouth, respectively through the oil inlet and outlet of stop valve 5 multiple tested high frequency mo single-action hydraulic cylinder 6 in parallel, the drain tap of tested high frequency mo single-action hydraulic cylinder 6 connects graduated cylinder 7 after pipeline is drawn, pressure sensor 9 is cylindrical shape, pressure sensor 9 one end connects the hydraulic rod end of tested high frequency mo single-action hydraulic cylinder 6, the other end linking springs deceleration loading device 10, change in time to detect hydraulic rod ouput force, after two four-way proportional reversing valves 2 commutate, spring loaded mechanism 10 impels the hydraulic rod of tested high frequency mo single-action hydraulic cylinder 6 to reset, displacement transducer 8 is arranged on hydraulic rod to detect hydraulic rod displacement over time.
First detection unit, can be inconsistent except tested high frequency mo single-action hydraulic cylinder 6 specifications and models in the 6th detection unit, and all the other elements are completely the same, and each element Placement is identical.
One first pressure transducer 26 is had to be arranged on proportional pressure control valve 25 in-line with detection system pressure.
There is one second pressure transducer 4 to be arranged on the A mouth place of two four-way proportional reversing valves 2, change in order to the pressure detecting the tested high frequency mo single-action hydraulic cylinder 6 in the first detection unit 11, second detection unit 12 in parallel with A mouth, the 3rd detection unit 13.
Have one the 3rd pressure transducer 3 to be arranged on the B mouth place of two four-way proportional reversing valves 2, the pressure in order to the tested high frequency mo single-action hydraulic cylinder 6 of detection four detection unit 14 in parallel with B mouth, the 5th detection unit 15, the 6th detection unit 16 changes.
For this testing apparatus, proportional pressure control valve 25 sets up system pressure, two four-way proportional reversing valves 2 can set high-frequency commutation action (reaching as high as 30Hz), under the commutation action of selector valve, 6 tested high frequency mo single-action hydraulic cylinders are divided into two groups alternately to complete the action of stretching out, retracting by hydraulic circuit; Energy storage module 1 plays a part to absorb impacts, and makes system pressure remain stable; Force feed filter 27 filter precision is high, ensures that proportional reversing valve 2 and 6 tested liquid cylinder pressures are to the requirement of high cleanliness fluid; Throttle valve 19 is arranged on system oil return road, for 6 oil hydraulic cylinders provide backhaul back pressure, makes oil hydraulic cylinder easy motion; Radiator 20 matches with heater 17, makes system oil temperature remain stable.
This durability test device is divided into operating mode and test pattern.Under operating mode, oil hydraulic cylinder carries out life consumption, and now proportional reversing valve 2 is in high frequency direction changing ratio state, makes oil hydraulic cylinder reach the requirement of to-and-fro motion number of times within a short period of time, saves test period; During test pattern, proportional reversing valve 2 is in lower commutating frequency, be suitable for detecting the performance index of oil hydraulic cylinder, the lowest starting pressure of high frequency mo single-action hydraulic cylinder in endurance test process, internal leakage, load efficiency curve, piston displacement response curve in time can be detected in test mode.Start test pattern after durability test device work a period of time under operating mode, complete after the performance index of oil hydraulic cylinder are detected, switch to operating mode.Two kinds of patterns automatically switch, and complete test, automaticity is high.
Adopt a test method for afore-mentioned test device, comprise the following steps:
Step one: operating mode, in order to detect the life consumption of tested high frequency mo single-action hydraulic cylinder 6;
Proportional pressure control valve 25 being set up system pressure is oil hydraulic cylinder rated working pressure, two four-way proportional reversing valves 2 are set as that the high frequency needed for endurance test commutates, regulate the back pressure that throttle valve 19 makes hydraulic system reach required, starting electrical machinery, driven by motor hydraulic pump works, testing apparatus brings into operation, and makes the certain number of times of oil hydraulic cylinder to-and-fro motion;
Step 2: test pattern, can detect the lowest starting pressure of high frequency mo single-action hydraulic cylinder in endurance test process, internal leakage, load efficiency curve, piston displacement response curve in time in test mode;
After tested high frequency mo single-action hydraulic cylinder 6 reciprocates to certain number of times, durability test device automatically switches to test pattern, now the commutating frequency of two four-way proportional reversing valves 2 is automatically switched to the specified commutating frequency of oil hydraulic cylinder by system, proportional pressure control valve 25 set pressure is still oil hydraulic cylinder rated working pressure, displacement transducer gathers corresponding hydraulic cylinder piston displacement response curve in time, and graduated cylinder gathers the internal leakage of corresponding oil hydraulic cylinder;
After certain hour information gathering terminates, the commutating frequency of proportional reversing valve 2 to be automatically switched 0.01Hz by system, the set pressure of proportional pressure control valve 25 was slowly elevated to the rated pressure of oil hydraulic cylinder uniformly in 50 seconds by 0MPa, now the data that gather of the 3rd pressure transducer 3, second pressure transducer 4 and each pressure sensor can obtain lowest starting pressure, the load efficiency curve of oil hydraulic cylinder as calculated after machine process;
In step 2, each index specifically obtains in the following ways; Two four-way proportional reversing valves 2 commutate to right position and detect the multiple detection units in parallel with A mouth, in the set pressure elevation process of proportional pressure control valve 25, the hydraulic rod of oil hydraulic cylinder 6 by static setting in motion until stroke terminate stop, the signal that displacement transducer 8 gathers can determine the hydraulic rod motion moment, and the force value that this moment second pressure transducer 4 gathers is the lowest starting pressure of oil hydraulic cylinder 6; Displacement transducer 8 can determine hydraulic rod run duration section, the force value that second pressure transducer 4 gathers within this period is multiplied with oil hydraulic cylinder rodless cavity piston area and can obtains the theoretical ouput force of oil hydraulic cylinder 6, and the force value that in this period, pressure sensor 9 gathers is the actual ouput force of oil hydraulic cylinder 6, the two is done than the load efficiency curve that can obtain oil hydraulic cylinder 6; In like manner, the multiple detection units in parallel with B mouth are detected when two four-way proportional reversing valves 2 commutate to left position.
Step 3, by the operating mode in step 1 and the test pattern alternate run in step 2, after off-test, drawn the durability performance index of oil hydraulic cylinder by computer disposal analysis by collected information.
Although more than describe in detail the preferred embodiments of the present invention, should be expressly understood that, for a person skilled in the art, the present invention can have various modifications and variations.All any amendments done within the spirit and principles in the present invention, equivalent replacement, improvement etc., all should be included within protection scope of the present invention.
Claims (4)
1., based on a high frequency single-action hydraulic cylinder durability test device for parallel power-saving technology, it is characterized in that: comprise
The oil hydraulic pump (23) rotated is driven by motor (24), oil hydraulic pump (23) in-line connects fuel tank (28) by stop valve, vent line connects one-way valve (21), one-way valve (21) rear oil duct is divided into two branch roads, one branch road is through proportional pressure control valve (25) oil sump tank (28), and another branch road connects force feed filter (27);
Force feed filter (27) the other end oil circuit is divided into two branch roads, one branch road connects the oil-feed interface of energy storage module (1), the draining road of energy storage module (1) connects fuel tank (28), and another branch road connects the P mouth of two four-way proportional reversing valves (2);
The T mouth hydraulic circuit of two four-way proportional reversing valves (2) connects fuel tank (28), A mouth multiple detection unit in parallel (11,12,13) simultaneously of two four-way proportional reversing valves (2), B mouth multiple detection unit in parallel (14,15,16) simultaneously of two four-way proportional reversing valves (2);
Each detection unit comprises stop valve (5), tested high frequency mo single-action hydraulic cylinder (6), graduated cylinder (7), displacement transducer (8), pressure sensor (9) and spring loaded mechanism (10), hydraulic circuit is drawn from the A mouth of two four-way proportional reversing valves (2) and B mouth, respectively through the oil inlet and outlet of stop valve (5) multiple tested high frequency mo single-action hydraulic cylinder (6) in parallel, the drain tap of tested high frequency mo single-action hydraulic cylinder (6) connects graduated cylinder (7) after pipeline is drawn, described pressure sensor (9) one end connects the hydraulic rod end of tested high frequency mo single-action hydraulic cylinder (6), the other end linking springs deceleration loading device (10), change in time to detect hydraulic rod ouput force, displacement transducer (8) is arranged on hydraulic rod to detect hydraulic rod displacement over time,
One first pressure transducer (26) is had to be arranged on proportional pressure control valve (25) in-line with detection system pressure;
There is one second pressure transducer (4) to be arranged on the A mouth place of two four-way proportional reversing valves (2), change in order to the pressure detecting tested high frequency mo single-action hydraulic cylinder (6) in parallel with A mouth;
There is one the 3rd pressure transducer (3) to be arranged on the B mouth place of two four-way proportional reversing valves (2), change in order to the pressure detecting tested high frequency mo single-action hydraulic cylinder (6) in parallel with B mouth.
2. according to claim 1 based on the high frequency single-action hydraulic cylinder durability test device of parallel power-saving technology, it is characterized in that: described fuel tank (28) inside is provided with the heater (17) to fluid heating, and in order to the temperature transducer detecting oil liquid temperature (18); The T mouth hydraulic circuit of two four-way proportional reversing valves (2) connects fuel tank (28) successively after throttle valve (19), radiator (20).
3. according to claim 1 based on the high frequency single-action hydraulic cylinder durability test device of parallel power-saving technology, it is characterized in that: A mouth three detection units in parallel simultaneously of described two four-way proportional reversing valves (2), are respectively the first detection unit (11), the second detection unit (12), the 3rd detection unit (13); B mouth three detection units in parallel simultaneously of two four-way proportional reversing valves (2), are respectively the 4th detection unit (14), the 5th detection unit (15), the 6th detection unit (16).
4., according to claim 1 based on the high frequency single-action hydraulic cylinder durability test device of parallel power-saving technology, it is characterized in that: described pressure sensor (9) is cylindrical shape.
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104847738A (en) * | 2015-06-03 | 2015-08-19 | 宁波恒力液压股份有限公司 | Parallel energy-saving technology based high-frequency single-acting hydraulic cylinder durability test device and method |
| CN114483712A (en) * | 2022-02-04 | 2022-05-13 | 浙江大学 | Hydraulic cylinder micro-internal leakage detection test bed and detection method thereof |
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2015
- 2015-06-03 CN CN201520375030.0U patent/CN204783954U/en active Active
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104847738A (en) * | 2015-06-03 | 2015-08-19 | 宁波恒力液压股份有限公司 | Parallel energy-saving technology based high-frequency single-acting hydraulic cylinder durability test device and method |
| CN104847738B (en) * | 2015-06-03 | 2017-01-25 | 宁波恒力液压股份有限公司 | Parallel energy-saving technology based high-frequency single-acting hydraulic cylinder durability test device and method |
| CN114483712A (en) * | 2022-02-04 | 2022-05-13 | 浙江大学 | Hydraulic cylinder micro-internal leakage detection test bed and detection method thereof |
| CN114483712B (en) * | 2022-02-04 | 2023-04-07 | 浙江大学 | Hydraulic cylinder micro-internal leakage detection test bed and detection method thereof |
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