CN204359476U - Magnetic flow liquid shear yielding force checking device under dynamic non-uniform magnetic-field - Google Patents

Abstract

The utility model relates to magnetic flow liquid shear yielding force checking device under dynamic non-uniform magnetic-field.This device comprises motor, shaft coupling, torque sensor, driving wheel, guide rail, slide block, sensor block, C shape pure iron, detects block, weight, support, engaged wheel, shell, solenoid, magnetic flow liquid, Hall element, fine rule, worktable.Whole device controls the break-make of motor and solenoid by Hall element, and two C shape pure iron with solenoid are for generation of the dynamic non-uniform magnetic-field of space distribution; Motor is connected by shaft coupling with torque sensor, and detection block and magnetic flow liquid are sealed in shell, and weight, engaged wheel, detection block, sensor block, driving wheel are connected by fine rule, is controlled their motion by motor and weight; Sensor block is fixed on above slide block, along slide, and can be respectively equipped with two Hall elements at guide rail two ends.This apparatus structure is ingenious, and degree of accuracy is high, can direct-detection model magnetic flow liquid shear yielding power.

Description

Magnetic flow liquid shear yielding force checking device under dynamic non-uniform magnetic-field

Technical field

The utility model relates to a kind of magnetic flow liquid shear yielding force checking device, especially relates to one magnetic flow liquid shear yielding force checking device under dynamic non-uniform magnetic-field.

Background technology

Within 1948, Rabinow has invented magnetic flow liquid the earliest, this is almost identical by the time of inventing with electrorheological fluid, because the shear yield stress of electrorheological fluid is lower, and there is the problem of high-voltage safety, thus more and more deep from the research of researchist to magnetic flow liquid since nineteen ninety.

Magnetic flow liquid is the suspending liquid that the magnetic polarization Granular composite of micron-scale is formed in non magnetic liquid (mineral oil, silicone oil etc.). under zero magnetic field conditions, magnetic flow liquid shows as the good liquid of flowing property; Within the short time (Millisecond), can become class solid state from free-pouring liquid rotating under strong magnetic field action, its intensity is characterized by shear yield stress; And this change is continuous print, reversible, not only original state is returned to after removing magnetic field. magnetic flow liquid is an important branch of current intellectual material research field, has broad application prospects in fields such as automobile, machinery, aviation, building, medical treatment.

The constitutive relation of magnetic flow liquid represents with bingham's plasticity model usually, and its formulation is:

$\left\{\begin{array}{cc}\mathrm{\&tau;}={\mathrm{\&tau;}}_0\left(H\right)\mathrm{sgn}\left(\stackrel{\&CenterDot;}{\mathrm{\&gamma;}}\right)+\mathrm{\&eta;}\stackrel{\&CenterDot;}{\mathrm{\&gamma;}}& \left|\mathrm{\&tau;}\right|\&GreaterEqual;{\mathrm{\&tau;}}_0\left(H\right)\\ \stackrel{\&CenterDot;}{\mathrm{\&gamma;}}=0& \left|\mathrm{\&tau;}\right|<{\mathrm{\&tau;}}_0\left(H\right)\end{array}\right.$

τ in formula ₀(H) be shear yield stress that externally-applied magnetic field causes; H is the magnetic field intensity of externally-applied magnetic field; η is plastic viscosity, is the ratio of shear yield stress and shear strain; γ is shear rate.

When magnetorheological device in the work environment, always there is disturbing magnetic field around, and this disturbing magnetic field is not exist with a stable state, and its space distribution and degree of strength thereof, all in the middle of constantly changing, therefore be can not ignore the impact of magnetorheological device.At present, many researchists are confined to the research to Shear Yield Stress of Magnetorheological Fluids under steady magnetic field, and this is not in full conformity with magnetic flow liquid actual condition operationally, causes magnetorheological device control accuracy operationally to decline, has a strong impact on its serviceability.For this reason, situation of change and the microcosmic Rheology Mechanism of studying the shear yield stress of magnetic flow liquid under dynamic non-uniform magnetic-field are significantly.

Utility model content

It is ingenious that the technical problems to be solved in the utility model is to provide a kind of structure, is easy to operation, easy to detect, is quick on the draw, magnetic flow liquid shear yielding force checking device under the dynamic non-uniform magnetic-field that degree of accuracy is high.

In order to effectively realize magnetic flow liquid shear yielding force checking device advantage as above under dynamic non-uniform magnetic-field, the utility model realizes as follows: this device is by motor, shaft coupling, torque sensor, driving wheel, guide rail, slide block, sensor block, C shape pure iron, detects block, weight, support, engaged wheel, shell, solenoid, magnetic flow liquid, Hall element, fine rule, worktable forms.Whole device controls the break-make of motor and solenoid by Hall element, be respectively equipped with two Hall elements at the two ends in the centre position of two guide rails: the Hall element away from motor drive direction controls the startup of motor and the energising of solenoid, the Hall element near motor drive direction controls the power-off of motor and the power-off of solenoid.Two C shape pure iron with solenoid are for generation of the dynamic non-uniform magnetic-field of space distribution, detection block and magnetic flow liquid are sealed in shell, weight, engaged wheel, detection block, sensor block, driving wheel are connected by fine rule, and by their motion of gravity control of motor and weight, sensor block is fixed on above slide block, and can along slide, motor is connected by shaft coupling with torque sensor, driving wheel is connected with torque sensor, and the shearing force of magnetic flow liquid is tried to achieve by the reading of torque sensor and the ratio of driving wheel radius.The material of shell and detection block is aluminium, detects on block and has the gap that width is 2mm, and for when detecting block and doing shearing motion, magnetic flow liquid is refluxed by this gap.

Under dynamic non-uniform magnetic-field described in the utility model, the good effect of magnetic flow liquid shear yielding force checking device is: this device introduces turn the stop transport dynamic and rheological phenomena of magnetic flow liquid and the introducing of torque sensor that Hall element controls motor and indirectly detects in real time the shearing force of magnetic flow liquid, do not need manual operation, while improve automatization level, improve accuracy of detection and the sensitivity of this pick-up unit.Because the automatization level of this device is high, make the workable, easy to detect of whole device, can direct-detection model magnetic flow liquid shear yielding power.

Accompanying drawing explanation

Figure is the structural principle schematic diagram of magnetic flow liquid shear yielding force checking device under the dynamic non-uniform magnetic-field of the utility model.

Embodiment

Below in conjunction with drawings and Examples, the utility model is further described.

In figure, magnetic flow liquid shear yielding force checking device under the dynamic non-uniform magnetic-field of the utility model, this device is made up of motor 1, shaft coupling 2, torque sensor 3, driving wheel 4, guide rail 5, slide block 6, sensor block 7, C shape pure iron 8, detection block 9, weight 10, support 11, engaged wheel 12, shell 13, solenoid 14, magnetic flow liquid 15, Hall element 16, fine rule 17, Hall element 18, worktable 19.Whole device controls the break-make of motor 1 and solenoid 14 by Hall element, be respectively equipped with two Hall elements at the two ends in the centre position of two guide rails 5: the Hall element 16 away from motor 1 direction controls the startup of motor 1 and the energising of solenoid 14, the Hall element 18 near motor 1 direction controls the power-off of motor 1 and the power-off of solenoid 14.Two C shape pure iron 8 with solenoid 14 are for generation of the dynamic non-uniform magnetic-field of space distribution, detection block 9 and magnetic flow liquid 15 are sealed in shell 13, weight 10, engaged wheel 12, detect block 9, sensor block 7, driving wheel 4 is connected by fine rule 17, and pass through their motion of gravity control of motor 1 and weight 10, sensor block 7 is fixed on above slide block 6, and can slide along guide rail 5, motor 1 is connected by shaft coupling 2 with torque sensor 3, driving wheel 4 is connected with torque sensor 3, the shearing force of magnetic flow liquid 15 is tried to achieve by the reading of torque sensor 3 and the ratio of driving wheel 4 radius.The material of shell 13 and detection block 9 is aluminium, has the gap that width is 2mm on detecting 9 pieces, and for when detecting block 9 and doing shearing motion, magnetic flow liquid 15 is refluxed by this gap.

The feature of this device is to introduce turn the stop transport dynamic and rheological phenomena of magnetic flow liquid 15 and the introducing of torque sensor 3 that Hall element controls motor 1 and indirectly detects in real time the shearing force of magnetic flow liquid 15, do not need manual operation, while improve automatization level, improve accuracy of detection and the sensitivity of this pick-up unit.Because the automatization level of this device is high, make the workable, easy to detect of whole device, can direct-detection model magnetic flow liquid shear yielding power.

The magnetic flow liquid 15 that will detect is sealed in shell 13, is energized to motor 1 and two solenoids 14.Because weight 10, engaged wheel 12, detection block 9, sensor block 7, driving wheel 4 are connected by fine rule 17, the initial position of sensor block 7 is in guide rail 5 one end away from motor 1 direction, now solenoid 14 and motor 1 are energized, generation non-uniform magnetic-field around magnetic flow liquid 15, motor 1 drives fine rule 17 to make to detect block 9 and do shearing motion to magnetic flow liquid 15 inside shell 13 simultaneously, and shearing force is directly obtained by following formula by the moment of torsion be presented on torque sensor 3 liquid crystal display:

T _{torque sensor}=(m _weightg+F _{shearing force}) r _{driving wheel}

Calculate the shearing force of magnetic flow liquid 15, this completes the detection of the shear yielding power of the magnetic flow liquid 15 detected in block 9 track of passing by under different magnetic field.When the Hall element 18 near motor 1 direction senses sensor block 7, solenoid 14 and motor 1 power-off, under the effect of weight 10, haul fine rule 17 to go back, make to detect block 9 and get back to initial position, Hall element 16 away from motor 1 direction has sensed again sensor block 7, solenoid 14 and motor 1 are energized, now change the power of the non-uniform magnetic-field being adjusted space distribution by the size of current of solenoid 14, repeat again above action, so just detected the size of the shear yielding power of magnetic flow liquid 15 under dynamic non-uniform magnetic-field.

Claims (2)

1. magnetic flow liquid shear yielding force checking device under dynamic non-uniform magnetic-field, this device is made up of motor, shaft coupling, torque sensor, driving wheel, guide rail, slide block, sensor block, C shape pure iron, detection block, weight, support, engaged wheel, shell, solenoid, magnetic flow liquid, Hall element, fine rule, worktable; It is characterized in that: be respectively equipped with two Hall elements at the two ends in the centre position of two guide rails (5), described Hall element (16) controls the startup of motor (1) and the energising of solenoid (14), and Hall element (18) controls the power-off of motor (1) and the power-off of solenoid (14); Described two the C shape pure iron (8) with solenoid (14) are for generation of the dynamic non-uniform magnetic-field of space distribution; Described detection block (9) and magnetic flow liquid (15) are sealed in shell (13); Described weight (10), engaged wheel (12), detection block (9), sensor block (7), driving wheel (4) are connected by fine rule (17), and pass through their motion of gravity control of motor (1) and weight (10); Described sensor block (7) is fixed on above slide block (6), and can slide along guide rail (5); Described motor (1) is connected by shaft coupling (2) with torque sensor (3), and described driving wheel (4) is connected with torque sensor (3).

2. dynamic magnetic flow liquid shear yielding force checking device under non-uniform magnetic-field as claimed in claim 1, is characterized in that: the material of described shell (13) and detection block (9) is aluminium; Described detection block (9) has the gap that width is 2mm.