CN201909747U - Heating and temperature detection mechanism for magnetorheological material tester - Google Patents

Abstract

The utility model discloses a magnetorheological material testing equipment heating and temperature detection mechanism, which is characterized in that it comprises a fixed ring, the fixed ring is located above the shear ring and can form an outer end on the mating surface after being matched with the shear ring A closed magnetorheological fluid cavity, the upper surface of the fixed ring is provided with the same through hole as the magnetorheological fluid cavity, and also includes an electric heating device located on the upper surface of the fixed ring and a temperature control device set in the through hole on the upper surface of the fixed ring The probe, the electric heating device and the temperature probe are connected with the computer control center. The magnetorheological material testing equipment with the structure of the utility model can test the influence of temperature on the performance of the magnetorheological fluid, because the three factors affecting the magnetorheological fluid (temperature, magnetic field strength and shear strain rate) can all be controlled , so the performance parameters of the magnetorheological fluid can be detected more comprehensively.

Description

A magnetorheological material testing equipment heating and temperature detection mechanism

technical field

The utility model relates to the technical field of magnetorheological fluid, in particular to a heating and temperature detection mechanism of magnetorheological material testing equipment.

Background technique

Magnetorheological materials are a new type of intelligent materials, including magnetorheological grease, magnetorheological elastoplastic, magnetorheological fluid, etc., among which magnetorheological fluid is the most widely studied and applied. Magneto-rheological fluid is a suspension mixture formed by micron-sized ferromagnetic particles evenly distributed in a specific solvent. When there is no external magnetic field, the rheological properties are similar to ordinary Newtonian fluids, but it can produce The magnetorheological effect (Magnetorheological Effect MRE), that is, the apparent viscosity can increase several orders of magnitude in milliseconds, showing solid-like mechanical properties, and the shear stress and viscosity change reversibly with the magnetic field. This is because when the magnetorheological fluid is under the action of a strong magnetic field, its suspended magnetic particles are induced into strong magnetism, forming a "chain" bridge between the magnetic poles, making it change from liquid to viscous solid in an instant.

Since the invention of magnetorheological fluid by Rabinow in 1948, it has had certain theoretical research and application practice in many engineering fields such as machinery, aerospace, petroleum, and civil engineering. With the development of scientific and technological production practice, its application is becoming wider and wider, and new formulas of magnetorheological fluids are constantly appearing. Therefore, how to test the performance of the newly produced magnetorheological fluid requires special testing equipment.

There are already some techniques for detecting the performance of magnetorheological fluids in the prior art, such as a kind of rheological testing equipment for magnetorheological polishing fluid published in China's utility model patent No. ZL200810030896.2, which includes a computer, a bracket and a The torque measuring device, the magnetic field generating device, the shearing mechanism and the driving mechanism on the support, the torque measuring device, the magnetic field generating device and the driving mechanism are connected with the computer, and the shearing mechanism installed in the magnetic field generating device includes a shearing ring and a fixing ring , the shear ring is located above the fixed ring, and the outer circumferences of the shear ring and the fixed ring are respectively provided with a shear ring edge and a fixed ring edge with a certain height, and the shear ring edge and the fixed ring edge are formed for A liquid storage groove for storing the magnetorheological polishing liquid, a rotating shaft connected to the drive mechanism is arranged above the center of the disc-shaped shear ring, and a connecting shaft connected to the torque measuring device is arranged below the center of the fixed ring. The utility model has the advantages of simple and compact structure, low cost, convenient control, stable test and high precision.

Another example is a test system for the rheological characteristics of magnetorheological fluids published in my country's utility model patent application number 01113648.0. Hall plate for measuring magnetic field strength. Its cavity is a barrel-shaped airtight container composed of an upper and a lower equal-diameter disc made of two magnetically conductive materials, and a ring made of non-magnetically conductive material fixedly connected around the lower disc. The main shafts of the feed motors are connected, and the lower disc shaft is connected with a lifting mechanism. Near the barrel-shaped container, two or more excitation coils are arranged symmetrically on the axes of the upper and lower disks, and the Hall plates and strain gauges are respectively arranged under the surface of the lower disk and on the surface of the lower disk axis. The magnetic field distribution of the device is uniform, the R/h ratio is high, the torque measurement part is set on a stationary shaft made of non-magnetic material, and will not be affected by the magnetic field force and the support friction torque, and the measurement accuracy is improved.

These existing detection devices can detect some characteristics of the magnetorheological fluid, but cannot detect the more comprehensive performance of the magnetorheological fluid, such as the influence of temperature on the performance of the magnetorheological fluid. Therefore, there is a defect that the detection function is limited.

Utility model content

Aiming at the deficiencies of the above-mentioned prior art, the technical problem to be solved by the utility model is: to provide a magnetorheological material testing equipment heating and temperature detection mechanism, so that the magnetorheological material testing equipment obtained based on this mechanism can be more comprehensively The performance of the magnetorheological fluid was detected.

In order to solve the problems of the technologies described above, the following technical solutions are adopted in the utility model:

A heating and temperature detection mechanism for magnetorheological material testing equipment, characterized in that it includes a fixed ring, which is located above the shear ring and can form a magnetorheological ring with a closed outer end on the mating surface after being matched with the shear ring. The upper surface of the fixed ring is provided with the same through hole as the magnetorheological liquid chamber, and also includes an electric heating device located on the upper surface of the fixed ring and a temperature probe arranged in the through hole on the upper surface of the fixed ring. The heating device and the temperature probe are connected with the computer control center.

In this technical solution, an electric heating device is arranged on the upper surface of the fixing ring, and the temperature of the electric heating device can be controlled through a computer control center, and the temperature can be detected in real time through a temperature probe. The temperature probe is set in the through hole, through which the heat of the electric heating device can be more easily transferred to the magnetorheological fluid cavity, and the temperature probe is set in the magnetorheological fluid cavity, so that the magnetic flow can be detected The temperature of the variable fluid is more accurate. In this way, the temperature of the magnetorheological fluid can be controlled and detected through the utility model, which is convenient for detecting the influence of temperature on the performance of the magnetorheological fluid, and can detect the performance of the magnetorheological fluid more comprehensively, and also has test results The advantage of precision.

The applicant also designed a magnetorheological material testing device based on the above heating and temperature detection mechanism, the structure of which is as follows.

A magneto-rheological material testing device, comprising a frame, the frame is provided with:

A magnetic field generating device, the magnetic field generating device includes an upper magnetic pole and a lower magnetic pole, the upper magnetic pole includes a vertically arranged upper bush made of pure electric iron and an electromagnetic coil winding outside the upper bush, and the lower magnetic pole includes a vertical The lower bushing made of electric pure iron and the electromagnetic coil winding outside the lower bushing, the upper end of the lower bushing has a step extending outward; the upper bushing and the electromagnetic coil winding outside the upper bushing are fixed On the upper connecting plate, the upper connecting plate is connected to the frame, the lower bushing and the electromagnetic coil winding outside the lower bushing are fixed on the lower connecting plate, and the lower connecting plate is fixed on the frame;

Shearing mechanism, the shearing mechanism includes a rotating shaft arranged concentrically, a shearing ring made of a weak magnetic material, and a fixed ring; the rotating shaft is vertically arranged inside the lower bush by bearings, and the motor is connected to the bottom of the rotating shaft through a reducer The shearing ring is installed and fixed on the upper end of the rotating shaft; the upper surface of the fixed ring has an assembly round platform, and the side wall of the assembly circular platform is provided with a positioning key; the upper surface of the shearing ring is coaxially provided with an annular The magnetorheological fluid tank for releasing the magnetorheological fluid. The position of the magnetorheological fluid tank corresponds to the position of the step extending outward from the upper end of the lower bushing. The bottom of the magnetorheological fluid tank is embedded with a lower circle made of pure electric iron. Ring piece, the height of the outer wall of the magnetorheological fluid tank is higher than the inner wall, an annular overflow groove is arranged coaxially in the inner ring of the magnetorheological fluid groove, and an annular ball groove is arranged coaxially in the inner ring of the overflow groove , balls are installed in the ball groove; the lower surface of the fixed ring is provided with an annular boss corresponding to the magneto-rheological fluid tank, and the annular boss is embedded in the fixed ring by an upper ring piece of pure electric iron material Obtained above, the position of the upper ring piece corresponds to the position of the lower end of the upper bushing; after the shear ring and the fixed ring are bonded together, a magnetorheological fluid cavity with a closed outer end can be formed in the magnetorheological fluid tank. An overflow chamber communicated with the magnetorheological fluid chamber is formed in the groove, and at the same time, the shear ring and the fixed ring can form a rolling friction fit through balls; the upper surface of the fixed ring is provided with a through hole communicated with the overflow chamber;

The shear stress detection mechanism includes a force transmission cylinder arranged inside the upper bushing. The lower end of the inner wall of the force transmission cylinder is provided with a keyway. The positioning key is slidably fitted in the keyway inside the force transmission cylinder, the upper end of the force transmission cylinder is fixed on the upper connecting plate, and a concave step is arranged on the outer wall of the force transmission cylinder, and a shear stress sensor is arranged on the concave step;

The heating and temperature detection mechanism includes an electric heating device located on the upper surface of the fixed ring and a temperature probe arranged in the through hole on the upper surface of the fixed ring;

The lifting mechanism includes several positioning poles fixed vertically around the magnetic field generating device and a third connecting plate fixedly connected above the upper connecting plate, and the upper connecting plate and the third connecting plate are slidably sleeved on the On the positioning pole; the lifting mechanism also includes a vertically arranged screw rod, the middle part of the screw rod is rotatably fitted on the frame by threads, and the lower end of the screw rod passes downward through the third connecting plate and is provided with a supporting tray , a ring of balls is arranged between the bearing tray and the third connecting plate, and the support and rolling friction fit of the third connecting plate are realized by the balls, and a handle is arranged horizontally on the upper end of the screw rod;

A control system, the control system includes a computer control center and the motor connected to the computer control center, electromagnetic coil windings, shear stress sensors, electric heating devices and temperature probes.

In this test equipment, put the magnetorheological fluid to be tested into the magnetorheological fluid tank of the shear ring, close the fixed ring, and control the upper magnetic pole to press down through the lifting mechanism so that the assembly round platform of the fixed ring is assembled into the In the force transmission cylinder, the starting motor drives the shearing ring to rotate, so that the shearing ring and the fixed ring rotate relative to each other, and then the detection starts. During detection, the shear strain rate can be adjusted by controlling the motor speed through the control system, and the actual shear stress can be detected by the shear stress sensor; the temperature can be adjusted by the electric heating device, and the actual temperature of the magnetorheological fluid can be detected by the temperature probe; by controlling the electromagnetic coil The magnitude of the winding current controls the magnetic field strength; in this way, the linear relationship between the shear stress of the magnetorheological fluid and temperature, shear strain rate, and magnetic field strength can be detected and calculated, and the characteristics of the magnetorheological fluid to be detected can be obtained. Among them, since there is a strict corresponding relationship between the magnetic field generated by the electromagnetic coil winding and the current of the electromagnetic coil winding, there is also a strict corresponding relationship between the motor current and the shearing ring speed, so the corresponding relationship can be detected first and preset through the program In the computer control center of the control system, when the test equipment is working, it directly adjusts the magnetic field of the electromagnetic coil winding by controlling the current of the electromagnetic coil winding, and controls the speed of the shearing ring by controlling the motor current, so there is no need to separately set up a magnetic field detection mechanism and a speed detection mechanism , and the temperature change is easily affected by the outside world, so it is necessary to set the temperature probe to detect the actual temperature of the magnetorheological fluid, so that the accuracy of the final measurement result can be guaranteed.

In this test equipment, the rack can be set as a frame structure to support the rest of the components. The upper bushing and lower bushing made of pure electric iron in the magnetic field generating device can concentrate the magnetic field generated by the electromagnetic coil to the middle, and increase the magnetic flux at the position of the shearing ring and the fixing ring located in the middle of the upper magnetic pole and the lower magnetic pole , especially the upper end of the lower bushing has an outwardly extended step, which extends to the position corresponding to the position of the magnetorheological fluid chamber obtained after the shear ring and the fixed ring are closed, and the position of the lower end of the upper bushing is also the same as the position of the magnetorheological fluid cavity. The positions of the liquid chambers are corresponding, so the magnetic flux at the magnetorheological liquid chamber can be further maximized, so that fewer coils and reduced coil currents can be used to generate a larger magnetic flux required for the test, which indirectly reduces the implementation cost of the device. In the magnetic field generating device, the lower connecting plate is directly fixed on the frame, and the upper connecting plate can move relative to the frame through the cooperation of the lifting mechanism. In the shear mechanism, the motor is connected through a reducer and drives the shear ring to rotate, providing shear power and adjusting the shear strain rate by controlling the motor. Wherein said shearing ring refers to that the shearing ring rotates and provides shearing force during the test, but the actual shearing ring is fixedly assembled on the lower magnetic pole, and the said fixed ring refers to that the fixed ring is fixed in the circumferential direction during the test. It does not move, but actually the fixing ring is only limited but not fixed; the shearing ring and the fixing ring are made of weak magnetic materials, preferably brass, but other weak magnetic materials can also be used. The lower ring piece and the upper ring piece made of electrical pure iron provided in the shearing mechanism can also achieve the effect of further increasing the magnetic flux at the position of the magnetorheological liquid cavity. embedded in. The overflow cavity formed by the overflow groove provided can play the following roles. One is to reduce the friction plane between the fixed ring and the shear ring, so that the rotational friction and shear force between the fixed ring and the shear ring can be concentrated on the magnetic flow as much as possible. Second, because the test equipment is equipped with an electric heating device, when the test temperature affects the magnetorheological fluid, the magnetorheological fluid may expand after being heated, so that the expanded magnetorheological fluid It can enter the overflow chamber to avoid affecting the experimental results. The third is that the upper surface of the fixed ring corresponding to the overflow cavity is provided with a through hole communicating with the overflow cavity, so that the heat of the electric heating device arranged on the upper surface of the fixed ring is more easily transferred to the magnetorheological fluid in the overflow cavity through the through hole, Since the overflow cavity is connected to the magnetorheological fluid cavity, the temperature of the magnetorheological fluid at the two places is basically the same, and the temperature of the magnetorheological fluid can be detected by the temperature probe installed in the through hole, which facilitates temperature detection and makes the temperature The detection result is more accurate. At the same time, since the shearing ring rotates during the test, the magnetorheological fluid will not escape from the through hole of the overflow cavity due to the action of a certain centrifugal force. The height of the outer wall of the magnetorheological fluid tank is higher than that of the inner wall, which can strengthen the blocking and sealing effect on the magnetorheological fluid, and prevent the magnetorheological fluid from running out of the gap outside the magnetorheological fluid chamber under the action of centrifugal force. The set ball grooves and balls can also further reduce friction, so that the rotational shear friction between the shear ring and the fixed ring is mainly concentrated at the magneto-rheological fluid, thereby improving detection accuracy. In the shear stress detection mechanism, the shear force is transmitted through the force transmission cylinder, the upper end of the force transmission cylinder is fixed on the upper connecting plate, and the lower end is slidably matched with the positioning key of the fixed ring assembly round table through the keyway to transmit the torque. A shear stress sensor is arranged on the concave step of the outer wall to detect the shear stress. The shear stress sensor may be a half-bridge patch or other forms of shear stress sensor in the prior art, which are not detailed here because they belong to the content of the prior art. In the heating and temperature detection mechanism, the electric heating device can specifically adopt the structure of surrounding resistance wire heating, wherein the electric heating device and the temperature probe all belong to the existing mature technology content, and the utility model makes a contribution to the prior art The most important thing is that the electric heating device and temperature probe are used in this position, so that the test equipment can detect the influence of temperature on the performance of magnetorheological fluid, not the structure of the electric heating device and temperature probe itself, so it will not be described in detail here . The setting of the lifting mechanism can lift the upper magnetic pole, facilitate the installation and disassembly of the fixed ring, and facilitate the replacement of the magnetorheological fluid. Sliding fit, so during the test, the position of the upper magnetic pole can also be adjusted at a certain height (a certain height refers to the length range of the key and keyway mating section), and the performance change of the magnetorheological fluid at different magnetic field positions can be detected. When the lifting mechanism is working, the rotating handle drives the screw rod to move upward, which can drive the third connecting plate through the supporting tray and then drive the upper connecting plate and the upper magnetic pole to move upward. When the rotating handle drives the screw rod to move downward, the upper connecting plate and the upper magnetic pole move upward. The poles can move downward under the action of their own weight. The positioning pole is used for guidance to ensure the alignment of the upper magnetic pole and the lower magnetic pole. The lifting mechanism itself also has the advantages of simple structure, labor-saving operation, purely mechanical structure and low price. In the control system, the computer control center is an integrated upper-level concept, and the computer control center integrates temperature control functions required for control testing, digital display adjustment functions, motor frequency conversion functions, magnetic field and magnetic field change gradient control functions, Functions such as the speed control function of the shaft coupling all belong to common knowledge in the field of electrical control, and do not belong to where this application contributes to the prior art, so they will not be described in detail here.

In summary, the magnetorheological material testing equipment obtained based on the utility model can test the influence of temperature on the performance of the magnetorheological fluid compared with the existing testing equipment due to the addition of heating and temperature detection mechanisms. , since the three factors affecting magnetorheological fluid (temperature, magnetic field strength and shear strain rate) and the gradient of the factors can be controlled, the performance parameters of magnetorheological fluid can be detected more comprehensively. At the same time, it also has the advantages of more accurate detection results and better detection effects.

Description of drawings

Fig. 1 is a schematic structural view of a magnetorheological material testing device based on the structure of the present invention.

Fig. 2 is a schematic diagram of the structure at the upper magnetic pole alone in Fig. 1 .

FIG. 3 is a schematic diagram of the structure at a single lower magnetic pole in FIG. 1 .

Fig. 4 is a schematic diagram of the structure of the separate fixing ring and the shearing ring in Fig. 1 .

Detailed ways

The structure of the present invention will be further described in detail below in conjunction with the accompanying drawings and a magnetorheological material testing device adopting the structure of the present invention.

As shown in Figures 1 to 4, a magnetorheological material testing device includes a frame 1, and the frame 1 is provided with:

A magnetic field generating device, the magnetic field generating device includes an upper magnetic pole and a lower magnetic pole, the upper magnetic pole includes a vertically arranged upper bushing 2 made of electric pure iron and an electromagnetic coil winding 3 outside the upper bushing, the lower magnetic pole It includes a vertically arranged lower bush 4 made of pure electric iron and an electromagnetic coil winding 5 located outside the lower bush. The upper end of the lower bush 4 has a step extending outward; the upper bush 2 and the upper bush The external electromagnetic coil winding 3 is fixed on the upper connecting plate 6, and the upper connecting plate 6 is connected to the frame 1, and the electromagnetic coil winding 5 outside the lower bushing 4 and the lower bushing is fixed on the lower connecting plate 7, and the lower connecting plate 7 is fixed on the frame 1; during implementation, each of the electromagnetic coil windings includes a multi-layer coil obtained by winding adjacently and side by side with an enameled wire in turn, each layer of coils is separated by insulating paper, and the outside of the electromagnetic coil winding Wrapped with insulating paper;

A shearing mechanism, which includes a rotating shaft 8 coaxially arranged, a shearing ring 9 made of a weak magnetic material, and a fixed ring 10; the rotating shaft 8 is vertically arranged inside the lower bushing 4 by a bearing 11, and the rotating shaft 8 below is connected to motor 13 through reducer 12; Described shearing ring 9 is installed and fixed on the upper end of rotating shaft 8; The upper surface of described fixed ring 10 has an assembly round table 14, and the side wall of assembly round table 14 is provided with positioning key 15; The upper surface of the cutting ring 9 is coaxially provided with an annular magnetorheological fluid tank 16 for holding the magnetorheological fluid. The position of the magnetorheological fluid tank 16 corresponds to the position of the step extending outward from the upper end of the lower bushing 2 , the bottom of the magnetorheological fluid tank 16 is embedded with a lower ring piece 17 made of electrical pure iron, the height of the outer wall of the magnetorheological fluid tank 16 is higher than the inner wall, and the inner ring of the magnetorheological fluid tank 16 is coaxially arranged There is an annular overflow groove 18, and an annular ball groove is arranged coaxially in the inner ring of the overflow groove, and balls 19 are installed in the ball groove; the lower surface of the fixed ring 10 is set corresponding to the magnetorheological fluid groove 16 There is an annular boss, which is obtained by embedding an upper ring piece 20 of pure electric iron material on the fixed ring 10, and the position of the upper ring piece 20 corresponds to the position of the lower end of the upper bushing 2; the scissors After the cutting ring 9 and the fixed ring 10 are bonded together, a magnetorheological fluid cavity with a closed outer end can be formed in the magnetorheological fluid tank 16, and an overflow cavity communicating with the magnetorheological fluid cavity can be formed in the overflow tank 18. At the same time, the shear ring 9 and the fixed ring 10 can form a rolling friction fit through the ball 19 (the remaining bonding surfaces of the shear ring and the fixed ring leave a gap of about 0.5mm during specific implementation); the upper surface of the fixed ring 10 is provided with a The through hole 22 connected to the overflow chamber;

The shear stress detection mechanism includes a force transmission cylinder 23 arranged inside the upper bushing 2, the lower end of the inner wall of the force transmission cylinder 23 is provided with a keyway 24, and the assembly round table 14 on the upper surface of the fixed ring 10 can be inserted into the force transmission cylinder 23 Inside and make the positioning key 15 on the assembly round table 14 slideably fit in the keyway 24 inside the force transmission cylinder 23, the upper end of the force transmission cylinder 23 is fixed on the upper connecting plate 6, and the outer wall of the force transmission cylinder 23 is provided with a concave Step, the concave step is provided with a shear stress sensor 25;

The heating and temperature detection mechanism includes an electric heating device 26 located on the upper surface of the fixed ring 10 and a temperature probe 27 arranged in the through hole 22 on the upper surface of the fixed ring 10;

The lifting mechanism includes several positioning uprights 28 vertically fixedly arranged around the magnetic field generating device and a third connecting plate 34 fixedly connected to the top of the upper connecting plate 6, the upper connecting plate 6 and the third connecting plate 34 can be Slidingly socketed on the positioning pole 28; the lifting mechanism also includes a vertically arranged screw rod 29, the middle part of the screw rod 29 is rotatably fitted on the frame 1 by threads, and the lower end of the screw rod 29 passes downwards The third connecting plate 34 is also provided with a supporting tray 30, a circle of balls 31 is arranged between the supporting tray 30 and the third connecting plate 34, and the bearing and rolling friction fit of the third connecting plate 34 are realized by the balls 31, and the screw rod 29 The upper end is horizontally provided with a handle 32; the upper end of the positioning vertical rod 28 of the lifting mechanism is a cone section with an upward tip, and the lower end of the positioning vertical rod 28 is a cylindrical section;

A control system, the control system includes a computer control center 33 and the motor 13 connected to the computer control center 33 , electromagnetic coil windings, shear stress sensor 25 , electric heating device 26 and temperature probe 27 .

Claims (1)

1. a magnetorheological materials testing apparatus is heated and temperature testing organization, it is characterized in that, comprise set collar, set collar be positioned at shearing ring top and with can form the magnetorheological sap cavity that an outer end is sealed at mating surface after shearing ring cooperates, described set collar upper surface is provided with the through hole identical with magnetorheological sap cavity, also comprise electric heater unit that is positioned at the set collar upper surface and the temp probe that is arranged at set collar upper surface through hole, described electric heater unit links to each other with computer controlling center with temp probe.

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