CN210639028U - Comprehensive experiment platform for material stress characteristic analysis - Google Patents

Abstract

The utility model provides a comprehensive experimental platform for analyzing material stress characteristics, which utilizes the connection of a double-rod oil cylinder with large output force and a swing oil cylinder with large output torque to form a new device, the two cylinders are respectively controlled to control the double-rod oil cylinder to obtain force and displacement, and the displacement can be used as an adjusting device to adapt to different samples and can also be used as a working stroke; the swing oil cylinder is controlled to obtain angular displacement and torque, and the angular displacement can be adjusted and also can be used as a working stroke; can be controlled logically simultaneously to obtain the stroke, angular displacement, force and torque required by work. The device occupies small space, can perform tensile stress analysis, compressive stress analysis, shear stress analysis, comprehensive stress analysis, various single fatigue stress analysis and comprehensive fatigue stress analysis, various symmetrical and asymmetrical fatigue stress analysis, can meet the requirements of various tests, and has wide application range.

Description

Comprehensive experiment platform for material stress characteristic analysis

Technical Field

The utility model relates to an experiment platform, in particular to material stress characteristic analysis comprehensive experiment platform.

Background

The analysis of the stress characteristics of the material is a very important part for the research of new materials or the research of materials produced in a specific batch and a specific process, and is the basis for the design of engineering technicians. The analysis of the stress characteristics of materials is a fundamental study that is very important for various applications built on the basis of materials. The scientific and technological development of China misses the research accumulation stage of the old-fashioned industrialized country on the stress characteristics of basic materials, data of good and multiple materials only refers to data of foreign similar products, and due to the fact that the components and the processes of the materials are different, actual data can be greatly different from standard data, so that the data are dangerous sometimes and unnecessary waste sometimes in engineering application, and the local reasons are manifold, one of the main reasons is that the amount of analysis equipment is expensive, and the number of test means is small.

Disclosure of Invention

For the defect of solving material stress test among the prior art, the utility model provides a test platform, this platform can cooperate different hydraulic control, forms multiple test mode, satisfies the stress test of material under various operating modes.

In order to achieve the above purpose, the utility model adopts the technical proposal that:

the utility model provides a material stress characteristic analysis comprehensive experiment platform, includes frame, test hydro-cylinder, hydraulic pressure source, control cabinet, and the test hydro-cylinder is installed in the frame, and the test hydro-cylinder passes through hydraulic line and hydraulic component and forms hydraulic circuit with the hydraulic pressure source, and the control cabinet passes through programmable control program control hydraulic circuit, the test hydro-cylinder comprises a swing hydro-cylinder and a two pole hydro-cylinders coaxial coupling, through spline coaxial coupling between two pole hydro-cylinders and the swing hydro-cylinder.

Further, install the spline on the last extension bar of two play pole hydro-cylinders or directly process out one section spline, the output of swing hydro-cylinder is connected with the spline housing, the last extension bar of two play pole hydro-cylinders slides from top to bottom in the spline housing, the spline housing internal diameter is greater than the external diameter of last extension bar, spline housing's bottom end processing is in spline fit's spline ring, the top of going up the extension bar is equipped with spacing step, when two play pole hydro-cylinders stretch out downwards, it is spacing to form the axial between spacing step and the spline ring.

Furthermore, a top plate can be arranged at the top of the rack, and the swing oil cylinder is vertically and downwards arranged on the top plate of the rack through a flange; the middle part of the frame is provided with a fixed platform, and the double-rod oil cylinder is vertically supported on the fixed platform downwards.

Further, the swing hydro-cylinder includes the casing, is equipped with hydraulic oil on the casing and advances, exports, installs piston, transmission sleeve and axis of rotation in the casing, and the coaxial cover of transmission sleeve is in the outside of axis of rotation, and the coaxial cover of piston is in the outside of transmission sleeve, and the internal tooth of piston and the meshing of the external tooth of transmission sleeve, the internal tooth of transmission sleeve and the external tooth meshing of axis of rotation form double gear drive.

Furthermore, the swing oil cylinder and the double-rod oil cylinder are respectively connected with an independent hydraulic source, and at least an electromagnetic valve and a pressure gauge are connected in series on a pipeline between the swing oil cylinder or the linear oil cylinder and the hydraulic source.

Further, the spline housing and the rotating shaft are integrated.

The experimental method of the comprehensive experimental platform for analyzing the stress characteristics of the material comprises the following steps:

(1) when the comprehensive test of stretching, compressing and shearing is carried out, oil inlets and oil return ports of a swing oil cylinder and a double-rod oil cylinder are respectively selected, an oil inlet electromagnetic valve on a pipeline connected with each oil inlet is opened and an oil return electromagnetic valve is closed, an oil return electromagnetic valve on a pipeline connected with each oil return port is opened and the oil inlet electromagnetic valve is closed, a hydraulic source is started to load, and the test is carried out;

(2) when a tensile or compression test is carried out, the electromagnetic valves of all pipelines connected with the swing oil cylinder are closed, the oil inlet and the oil return port of the double-rod oil cylinder are selected, the oil inlet electromagnetic valve on the pipeline connected with the oil inlet is opened, the oil return electromagnetic valve is closed, the oil return electromagnetic valve on the pipeline connected with the oil return port is opened, the oil inlet electromagnetic valve is closed, a hydraulic source is started for loading, and the test is carried out;

(3) when the shearing test is carried out, the electromagnetic valves of all pipelines connected with the double-rod oil cylinder are closed, an oil inlet and an oil return port of the swing oil cylinder are selected, an oil inlet electromagnetic valve on the pipeline connected with the oil inlet is opened, an oil return electromagnetic valve is closed, an oil return electromagnetic valve on the pipeline connected with the oil return port is opened, the oil inlet electromagnetic valve is closed, a hydraulic source is started to load, and the test is carried out;

(4) when the fatigue strength test is carried out, two oil ports of the swing oil cylinder or the double-outlet-rod oil cylinder correspond to pipelines to circularly and alternately feed oil and return oil, when one oil port feeds oil, an oil feed electromagnetic valve on the corresponding pipeline is opened, a return oil electromagnetic valve is closed, the other oil port corresponds to an oil feed electromagnetic valve on the pipeline and is closed, and the return oil electromagnetic valve is opened; through the control of a plurality of solenoid valves, two hydraulic fluid ports are oil inlet and oil return alternately, the swing oil cylinder rotates back and forth to form circulating shearing, and the double-outlet-rod oil cylinder extends and retracts circularly to form circulating stretching or compressing.

(5) When the fatigue strength test is carried out, the pressure reducing valve is adjusted to finish the fatigue strength test under a plurality of stresses or torques, and the pressure reducing valve corresponding to a single oil port is adjusted to finish the fatigue strength test under asymmetric stresses or torques.

After taking above technical scheme, the beneficial effects of the utility model are that:

the double-rod-out oil cylinder with large output force and the swing oil cylinder with large output torque are connected to form a new device, the two cylinders are respectively controlled to control the double-rod-out cylinder to obtain force and displacement, and the displacement can be used as an adjusting device to adapt to different samples and can also be used as a working stroke; the swing oil cylinder is controlled to obtain angular displacement and torque, and the angular displacement can be adjusted and also can be used as a working stroke; can be controlled logically simultaneously to obtain the stroke, angular displacement, force and torque required by work. The device occupies small space, can perform tensile stress analysis, compressive stress analysis, shear stress analysis, comprehensive stress analysis, various single fatigue stress analysis and comprehensive fatigue stress analysis, various symmetrical and asymmetrical fatigue stress analysis, can meet the requirements of various tests, and has wide application range.

Drawings

Fig. 1 is a perspective view of the present invention;

fig. 2 is a left side sectional view of the present invention;

FIG. 3 is a diagram showing the extended state of the double-rod cylinder;

FIG. 4 is a drawing showing the retracted state of the double-rod cylinder;

FIG. 5 is a hydraulic schematic of an intermittent pressure hold test;

FIG. 6 is a hydraulic schematic of a fatigue test;

fig. 7 is a hydraulic schematic diagram of a comprehensive experiment.

In the figure: the device comprises a frame 1, a top plate 2, a fixed platform 3, a swing oil cylinder 4, a shell 41, a piston 42, a transmission sleeve 43, a rotating shaft 44, a double-rod oil cylinder 5, a flange 6, a lower extension rod 7, an upper extension rod 8, a spline sleeve 9, a spline ring 10 and a limiting step 11.

Detailed Description

The following detailed description of the embodiments of the present invention is made with reference to the accompanying drawings:

as shown in the figure, the comprehensive experimental platform for analyzing the stress characteristics of the material comprises a rack 1, a test oil cylinder, a hydraulic source, a control console and the like. The top of the frame 1 can be provided with a top plate 2 or a cross beam for installing a test oil cylinder. The middle part of the frame 1 is provided with a fixed platform 3. The test cylinder body is fixedly arranged at the center of the bottom of the top plate 2 and can be fixedly connected in a conventional connecting mode such as welding, bolt connection and the like. The test oil cylinder is formed by coaxially connecting a swing oil cylinder 4 and a double-rod oil cylinder 5. The swing oil cylinder 5 is vertically and downwards arranged on the top plate 2 of the frame 1 through a flange 6; the flange 6 is cast on the cylinder housing body by means of integral casting. The cylinder body of the double-rod oil cylinder 5 is vertically and fixedly supported on the fixed platform 3 of the frame and can be fixed in a welding or bolt connection mode. The lower extension rod 7 of the double-extension-rod oil cylinder 4 vertically extends downwards out of the fixed platform 3. Through spline coaxial coupling between two play pole hydro-cylinders 5 and swing hydro-cylinder 4, install the spline on the last extension bar 8 of two play pole hydro-cylinders or directly process out a section spline, the output of swing hydro-cylinder 4 is connected with spline housing 9, and the last extension bar 8 of two play pole hydro-cylinders 5 slides from top to bottom in spline housing 9, and when swing hydro-cylinder 4's output was rotatory, the spline fit drove the upper and lower extension bar rotation transmission moment of torsion of two play pole hydro-cylinders.

The swing cylinder 4 is a double-gear-pair swing cylinder and comprises a housing 41, a piston 42, a transmission sleeve 43 and a rotating shaft 44 are installed in the housing 41, the transmission sleeve 43 is coaxially sleeved on the outer side of the rotating shaft 44, the piston 42 is coaxially sleeved on the outer side of the transmission sleeve 43, the inner teeth of the piston 42 are meshed with the outer teeth of the transmission sleeve 43, and the inner teeth of the transmission sleeve 43 are meshed with the outer teeth of the rotating shaft 44 to form double-gear transmission. The housing 41 has hydraulic oil inlets and outlets distributed on both sides of the piston, and when the piston 42 is pushed by high-pressure oil of the hydraulic source to move linearly, the piston 42 drives the transmission sleeve 43 to rotate, and the transmission sleeve 43 drives the rotating shaft 44 to rotate, so as to output torque. The utility model discloses a swing hydro-cylinder adopts the design of two-stage gear pair, and the profile of tooth and the drive ratio of optimizing simultaneously realize that the small-angle produces big moment of torsion for bear the requirement of big moment of torsion and fatigue design. In order to transmit the moment of torsion better, the utility model discloses set up spline housing 9 and axis of rotation 44 into an organic whole, through integrated into one piece processing, guaranteed the transmission precision, improved the reliability.

The swing oil cylinder 4 and the double-rod oil cylinder 5 are respectively connected with an independent hydraulic source, conventional hydraulic elements such as an electromagnetic valve, a one-way valve, an overflow valve, a pressure retaining valve and the like can be connected in series on a pipeline between the swing oil cylinder or the double-rod oil cylinder and the hydraulic source as required, and the independent work or the simultaneous work is controlled by a console. The control can adopt conventional control technologies in the field such as conventional PLC and the like, and the details are not repeated in the application.

The swing oil cylinder outputs forward and reverse small-angle swing, and the swing angle is related to the stroke of the piston and the transmission ratio of the two-stage gear. The extension rod of the double-extension-rod oil cylinder moves up and down, and the stroke of the extension rod is related to the stroke of the piston and the stroke of the upper extension rod spline. In order to avoid the double-rod oil cylinder 5 from being separated from the spline housing 9, the inner diameter of the spline housing 9 is larger than the outer diameter of the upper extension rod 8, the spline ring 10 matched with the spline is processed at the tail end of the bottom of the spline housing 9, the top end of the upper extension rod 8 is provided with a limiting step 11, and when the double-rod oil cylinder 5 extends to the limiting position, axial limiting is formed between the limiting step 11 and the spline ring.

In order to meet the requirement of user testing, a stress tester and a corresponding clamp can be installed on the lower extension rod of the double-extension-rod oil cylinder, and a test bench and a corresponding clamp are fixedly installed right below the fixed platform.

Because the output force and the input pressure of the double-rod hydraulic cylinder form a linear relation related to the internal friction force, the output torque and the input pressure of the swing oil cylinder form a linear relation related to the internal friction torque, the force and the torque can be indirectly determined according to a pressure gauge in a hydraulic system through an application program or table look-up, and the relative accurate pressure can be obtained by utilizing a marketized relatively economic digital pressure gauge, so that the relatively accurate force or torque can be calculated.

The utility model discloses in because it is fixed with swing hydro-cylinder and two play pole hydro-cylinders through the shaft coupling, can carry out following test to the sample under test when two hydro-cylinders collocation are used: such as tensile elastic stress analysis, yield stress analysis, compressive elastic stress analysis, shear yield stress analysis, tensile fatigue test or fatigue curve test, compressive fatigue test, shear fatigue stress analysis, symmetric or asymmetric fatigue stress analysis, tensile/compressive and shear simultaneous loading integrated stress analysis, and the like.

The following is a description of the specific implementation of the testing method of the present invention:

the first embodiment is as follows: stretching, compressing, shearing

As shown in FIG. 5, the swing cylinder can be combined with the balance valve, and by utilizing the characteristics of the friction force of the cylinder body and the almost zero leakage of the balance valve, under the condition that the pressure source stops supplying pressure, the tensile/compressive force or the torque is still kept on the workpiece, so that the uninterrupted observation of the sample is facilitated. The balance valve 1 is used for keeping the torque of the torque swing cylinder, and the balance valve 2 is used for keeping the loading of the stretching/compressing cylinder. The pressure gauges 1 and 2 are used for displaying the pressure of the torque swing oil cylinder or the torque obtained by table lookup, and the pressure gauges 3 and 4 are used for displaying the stretching/compressing pressure or the pulling/compressing force obtained by table lookup.

Example two: fatigue strength test

Fatigue strength is right the utility model relates to a pressure signal, there is not the flow, and test, very energy-conserving can just be accomplished to less hydraulic power unit. Because only pressure signals are adopted, the alternating pressure signals are mainly limited by the response time of the electromagnetic valve about 50ms, 100ms is required in a positive-negative one cycle, the stress frequency is 10Hz, and about 28 hours is required for 100 ten thousand cycles of operation. The fatigue load can be asymmetrical or symmetrical, and the load amplitude can be adjusted steplessly by the pressure valve.

As shown in fig. 6, the stress and full-spectrum fatigue test hydraulic schematic diagram, in the diagram, the control of the solenoid valve is completed by the PLC, the middle relay is not provided, and the solenoid valve 1, the solenoid valve 2 and the solenoid valve 12 are matched, so that the cyclic loading of the fatigue shear stress in a section of the fatigue shear stress in one direction (defined as a positive direction) can be completed by the pressure reducing valve 1 and the pressure reducing valve 2; the electromagnetic valve 1 and the electromagnetic valve 3 are cooperated with the electromagnetic valve 12 and the electromagnetic valve 11 which are matched, and the cyclic loading of the shearing positive reaction force can be formed through the pressure reducing valve 1 and the pressure reducing valve 3; the pressure gauge 1/2/3/4 is used to check the pressure provided by the pressure reducing valve 1/2/3/4 or the shear stress from a lookup table. Similarly, the solenoid valves 5, 6, 7 and 8 and the matched solenoid valves 13 and 14 can carry out various fatigue cycle loading and various stress loading on the stretching/compressing cylinder through the pressure reducing valves 5, 6, 7 and 8 and the pressure gauges 5, 6, 7 and 8. According to the designed application condition, all the electromagnetic valves and the electric control pressure reducing valves can be comprehensively utilized, and the loading or fatigue test which reflects the real application requirement and is more complex can be realized through programming control. Therefore, the platform is called as an experimental platform with a full-spectrum fatigue test function, has full functions, is relatively complex in a hydraulic circuit, and needs PLC programming or rapid switching of other programmable controllers to acquire the circulation needed by completing the fatigue test in a short time. Require highly to key model or factor of safety, can adopt this kind of mode, the utility model provides an alternative solution.

Example 3: combined tension and compression and shear loading test

The loading amplitude can be adjusted in a stepless mode, the actual working conditions can be completely copied at the same time, and guarantee is provided for specific application. Compared with the existing method for loading the shearing stress by the eccentric wheel, the method is simple to operate, can load the actual workpiece, can add other tensile/compressive stresses, is closer to the actual application, does not need to calculate simulation or calculate extension hypothesis for the experimental result, and directly reflects the real working condition.

As shown in fig. 7, the swing cylinder and the double-rod cylinder are respectively connected to independent oil pressure sources, a pressure reducing valve, a pressure gauge and an electromagnetic valve are arranged on each oil path, oil pressure is controlled by the pressure reducing valve, reversing, maintaining and the like of the oil paths are controlled by the electromagnetic valve, the pressure gauge reads a pressure value, and when the two cylinders are simultaneously controlled, a combined loading test of tension and compression and shearing with stepless adjustment of loading amplitude can be realized.

Claims (6)

1. A comprehensive experimental platform for analyzing material stress characteristics comprises a rack, a test oil cylinder, a hydraulic source and a console, wherein the test oil cylinder is installed on the rack, the test oil cylinder and the hydraulic source form a hydraulic loop through a hydraulic pipeline and a hydraulic element, and the console controls the hydraulic loop through a programmable control program.

2. The material stress characteristic analysis comprehensive experiment platform of claim 1, wherein a spline is installed on an upper extension rod of the double-extension-rod oil cylinder or a section of spline is directly processed, the output end of the swing oil cylinder is connected with a spline housing, the upper extension rod of the double-extension-rod oil cylinder slides up and down in the spline housing, the inner diameter of the spline housing is larger than the outer diameter of the upper extension rod, a spline ring matched with the spline is processed at the tail end of the bottom of the spline housing, a limiting step is arranged at the top end of the upper extension rod, and when the double-extension-rod oil cylinder extends downwards, axial limiting is formed between the limiting step and the spline ring.

3. The comprehensive material stress characteristic analysis experiment platform as claimed in claim 1, wherein a top plate can be arranged at the top of the rack, and the swing oil cylinder is vertically and downwardly mounted on the top plate of the rack through a flange; the middle part of the frame is provided with a fixed platform, and the double-rod oil cylinder is vertically supported on the fixed platform downwards.

4. The comprehensive material stress characteristic analysis experiment platform as claimed in claim 1, wherein the swing oil cylinder comprises a shell, a hydraulic oil inlet and a hydraulic oil outlet are formed in the shell, a piston, a transmission sleeve and a rotating shaft are installed in the shell, the transmission sleeve is coaxially sleeved on the outer side of the rotating shaft, the piston is coaxially sleeved on the outer side of the transmission sleeve, inner teeth of the piston are meshed with outer teeth of the transmission sleeve, and inner teeth of the transmission sleeve are meshed with outer teeth of the rotating shaft to form double-stage gear transmission.

5. The comprehensive material stress characteristic analysis experiment platform according to any one of claims 1 to 4, wherein two oil ports of the swing oil cylinder and the double-rod oil cylinder are respectively communicated with the output end of the hydraulic source through at least one pressure-reducing oil inlet oil way, and one oil return oil way is communicated with an oil tank of the hydraulic source; the pressure-reducing oil inlet oil path comprises a pressure-reducing valve, a pressure gauge and an oil inlet electromagnetic valve which are connected in series through pipelines; and an oil return electromagnetic valve is connected in series on the oil return oil path.

6. The comprehensive material stress characteristic analysis experiment platform according to claim 2, wherein the spline housing and the rotating shaft are integrated.

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