CN209946192U - Non-contact magnetic fluid rotating speed measuring device - Google Patents
Non-contact magnetic fluid rotating speed measuring device Download PDFInfo
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- CN209946192U CN209946192U CN201920783047.8U CN201920783047U CN209946192U CN 209946192 U CN209946192 U CN 209946192U CN 201920783047 U CN201920783047 U CN 201920783047U CN 209946192 U CN209946192 U CN 209946192U
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- 230000006698 induction Effects 0.000 claims abstract description 65
- 239000011248 coating agent Substances 0.000 claims abstract description 43
- 238000000576 coating method Methods 0.000 claims abstract description 43
- 238000001514 detection method Methods 0.000 claims abstract description 19
- 238000005259 measurement Methods 0.000 claims description 16
- 238000007789 sealing Methods 0.000 claims description 14
- 239000002585 base Substances 0.000 description 18
- 239000002245 particle Substances 0.000 description 15
- 239000011554 ferrofluid Substances 0.000 description 10
- 239000012530 fluid Substances 0.000 description 5
- 238000012360 testing method Methods 0.000 description 5
- 238000003754 machining Methods 0.000 description 3
- 238000000034 method Methods 0.000 description 3
- 239000000306 component Substances 0.000 description 2
- 230000007547 defect Effects 0.000 description 2
- 238000013461 design Methods 0.000 description 2
- 238000010892 electric spark Methods 0.000 description 2
- 238000009434 installation Methods 0.000 description 2
- 239000012212 insulator Substances 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
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- 239000008358 core component Substances 0.000 description 1
- 238000009826 distribution Methods 0.000 description 1
- 239000000428 dust Substances 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 230000017525 heat dissipation Effects 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 125000002887 hydroxy group Chemical group [H]O* 0.000 description 1
- 230000001939 inductive effect Effects 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 239000000696 magnetic material Substances 0.000 description 1
- 230000005389 magnetism Effects 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 238000005459 micromachining Methods 0.000 description 1
- 239000010705 motor oil Substances 0.000 description 1
- 239000003921 oil Substances 0.000 description 1
- 230000002035 prolonged effect Effects 0.000 description 1
- 238000001338 self-assembly Methods 0.000 description 1
- 239000002904 solvent Substances 0.000 description 1
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- 230000001360 synchronised effect Effects 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
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Abstract
The utility model discloses a non-contact magnetofluid rotating speed measuring device; the device comprises a speed measuring shaft and a speed measuring sleeve which are coaxially arranged, wherein the speed measuring sleeve is sleeved on the speed measuring shaft, and a gap is formed between the speed measuring shafts; the speed measuring sleeve is provided with a speed measuring cavity, a conductive coating, an induction electrode and a magnetic fluid are arranged in the speed measuring cavity, and the conductive coating and the induction electrode are externally connected with a current detection circuit and are coaxially arranged with a speed measuring shaft; a speed measuring magnet is fixed on the speed measuring shaft, and the speed measuring magnet and the induction electrode are arranged in the same radial direction; the speed measuring shaft is used for connecting the rotating speed output end of the object to be measured and synchronously driving the speed measuring magnet to rotate. Therefore, the speed measuring load of the speed measuring shaft is effectively reduced, and the safety, the stability and the application range of the speed measuring shaft are improved.
Description
Technical Field
The utility model relates to a rotational speed measuring device field especially relates to a non-contact magnetic current body rotational speed measuring device.
Background
The rotating speed measuring device is a measuring device which converts the rotating speed of a rotating object into electric quantity to be output. Most of the existing rotating speed measuring devices belong to indirect measuring devices, and common rotating speed measuring devices can be manufactured by methods such as machining, electromagnetic machining, mixed machining and the like. The rotation speed measuring devices can be classified into analog type and digital type according to different signal forms, and the rotation speed measuring devices are various in types and extremely wide in application. The commonly used rotating speed measuring devices include photoelectric type, capacitance type, variable reluctance type, tachogenerator and the like.
The prior art mainly measures the rotating speed by directly transmitting the rotating state, but the form causes a speed measuring device to generate a certain amount of load and resistance to a speed measuring shaft, and the phenomenon is particularly obvious in an electromechanical system. In addition, the bearing bush of the internal measuring device is easy to generate heat when being continuously rubbed under the condition of electrification, and even electric sparks can be generated after the bearing bush is worn, so that the performance of the electric connector is seriously influenced, and dangerous accidents are caused. And most of the current rotating speed measuring devices need to use precision micromachining to manufacture core components of the measuring devices, so that the measuring devices need complicated microstructures in design; this causes the poor stability of current rotational speed measuring device, security poor and application scope is little problem.
Therefore, the prior art has defects and needs to be improved and developed.
SUMMERY OF THE UTILITY MODEL
The to-be-solved technical problem of the utility model lies in, to the above-mentioned defect among the prior art, provide a non-contact magnetic current body rotational speed measuring device, it is little to aim at solving prior art rotational speed measuring device poor stability, security poor and application scope.
The utility model provides a technical scheme that technical problem adopted as follows: the utility model provides a non-contact magnetic current body rotational speed measuring device, measures the object rotational speed that awaits measuring through external current detection circuit, and it includes: the device comprises a speed measuring shaft and a speed measuring sleeve which are coaxially arranged, wherein the speed measuring sleeve is sleeved on the speed measuring shaft, and a gap is formed between the speed measuring shafts; the speed measuring sleeve is provided with a speed measuring cavity, a conductive coating, an induction electrode and a magnetic fluid are arranged in the speed measuring cavity, and the conductive coating and the induction electrode are externally connected with a current detection circuit and are coaxially arranged with the speed measuring shaft; a speed measuring magnet is fixed on the speed measuring shaft, and the speed measuring magnet and the induction electrode are arranged in the same radial direction; the speed measuring shaft is used for connecting the rotating speed output end of the object to be measured and synchronously driving the speed measuring magnet to rotate.
Furthermore, the non-contact magnetic fluid rotating speed measuring device further comprises an induction electrode ring, the induction electrode ring is fixed on the surface of the speed measuring cavity far away from the speed measuring shaft, and induction electrodes are arranged on the induction electrode ring at intervals.
Further, the speed measuring sleeve is hollow cylindrical, the speed measuring cavity is provided with a first inner surface close to the speed measuring shaft and a second inner surface relatively far away from the speed measuring shaft, the conductive coating is arranged on the first inner surface, and the induction electrode ring is arranged on the second inner surface.
Furthermore, the non-contact magnetic fluid rotating speed measuring device further comprises a base, and one end of the speed measuring sleeve is integrally connected with the base.
Furthermore, the one end that the speed measuring sleeve kept away from the base is provided with end cover, end cover sets up to ring shape.
Furthermore, a sealing permanent magnet is arranged between the speed measuring sleeve and the sealing end cover and close to the first inner surface.
Further, the non-contact magnetic fluid rotation speed measuring device further comprises a rotor, the rotor is arranged between the speed measuring shaft and the speed measuring sleeve, the rotor is fixed on the speed measuring shaft, a gap is arranged between the rotor and the speed measuring sleeve, and the speed measuring magnet is arranged on the surface, facing the speed measuring sleeve, of the rotor.
Furthermore, a rotor sinking groove is formed in the surface, facing the speed measuring sleeve, of the rotor, the speed measuring magnet is fixed to the rotor sinking groove through a fixing sliding block, and the fixing sliding block is fixed to the rotor in a threaded connection mode.
Furthermore, a shaft end baffle is arranged at the connecting end of the rotor and the speed measuring shaft.
Further, the rotor and the speed measuring shaft are detachably and fixedly connected through a fixed key; the rotor is provided with a first key position sinking groove on the surface contacting with the speed measuring shaft, the speed measuring shaft is correspondingly provided with a second key position sinking groove, and the fixed key is accommodated in the first key position sinking groove and the second key position sinking groove.
Compared with the prior art, the utility model provides a non-contact magnetic fluid rotating speed measuring device; the non-contact magnetic fluid rotating speed measuring device measures the rotating speed of an object to be measured through an external current detection circuit, and comprises: the device comprises a speed measuring shaft and a speed measuring sleeve which are coaxially arranged, wherein the speed measuring sleeve is sleeved on the speed measuring shaft, and a gap is formed between the speed measuring shafts; the speed measuring sleeve is provided with a speed measuring cavity, a conductive coating, an induction electrode and a magnetic fluid are arranged in the speed measuring cavity, and the conductive coating and the induction electrode are externally connected with a current detection circuit and are coaxially arranged with the speed measuring shaft; a speed measuring magnet is fixed on the speed measuring shaft, and the speed measuring magnet and the induction electrode are arranged in the same radial direction; the speed measuring shaft is used for being connected with the rotating speed output end of the object to be measured and synchronously driving the speed measuring magnet to rotate. And then the speed measuring load of the speed measuring shaft is reduced, and the safety, the stability and the application range of the speed measuring shaft are improved.
Drawings
Fig. 1 is a first schematic perspective view of a non-contact magnetic fluid rotation speed measuring device according to the present invention.
Fig. 2 is a second schematic perspective view of the non-contact magnetic fluid rotation speed measuring device of the present invention.
Fig. 3 is a schematic cross-sectional view of a non-contact magnetic fluid rotation speed measuring device according to the present invention.
Fig. 4 is an enlarged schematic view of a in fig. 3.
Fig. 5 is an enlarged schematic view B of fig. 3.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention clearer and clearer, the present invention will be described in further detail below with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
Referring to fig. 1, the present invention provides a non-contact magnetic fluid rotation speed measuring device 10, wherein the non-contact magnetic fluid rotation speed measuring device 10 realizes synchronous rotation with an object to be measured through a rotation output end (not shown) of an external object to be measured, and outputs a current pulse signal through an external current detection circuit (not shown), so as to calculate the rotation speed of the rotation output end according to the current pulse signal. The non-contact magnetic fluid rotating speed measuring device 10 comprises a speed measuring shaft 11 and a speed measuring sleeve 12, wherein the speed measuring sleeve 12 is sleeved on the speed measuring shaft 11; further, the speed measuring sleeve 12 and the speed measuring shaft 11 are coaxially arranged, and a gap is formed between the speed measuring sleeve 12 and the speed measuring shaft 11; i.e. the tacho shaft 11 and the tacho sleeve 12 do not touch each other. The speed measurement load and resistance borne by the speed measurement shaft 11 are effectively reduced, direct friction damage, heating and even electric spark generation of the speed measurement shaft 11 and the speed measurement sleeve 12 are effectively avoided, the service life of the non-contact type magnetic fluid rotating speed measuring device 10 is effectively prolonged, and the use stability and the use range of the non-contact type magnetic fluid rotating speed measuring device are improved; meanwhile, dangerous accidents are effectively avoided, and the safety and the application range of the device are improved.
With further reference to fig. 2, fig. 3 and fig. 4, further, the tachometer sleeve 12 is provided with a tachometer cavity 121, a conductive coating 122, an induction electrode 123 and a magnetic fluid (not shown) are disposed in the tachometer cavity 121, a gap is disposed between the induction electrode 123 and the conductive coating 122 in the conductive coating 122, that is, the induction electrode 123 and the conductive coating 122 are not in contact, and the magnetic fluid is filled in the tachometer cavity 121; meanwhile, the conductive coating 122 and the induction electrode 123 are externally connected with a current detection circuit and are coaxially arranged with the speed measuring shaft 11; specifically, the conductive coating 122 is externally connected with a current input end of a current detection circuit, and the sensing electrode 123 is externally connected with a current output end of the current detection circuit, that is, the conductive coating is connected with one electrode of the current detection circuit in the speed measurement cavity 121, and the sensing electrode 123 is connected with the other electrode of the current detection circuit in the speed measurement cavity 121; when the conductive coating 122 and the inductive electrode 123 are electrically conducted, the external circuit detection circuit generates a current signal; and further, controlling the non-contact magnetic fluid rotating speed measuring device 10 to output a current pulse signal by controlling the on and off of the conductive coating 122 and the induction electrode 123.
With further reference to fig. 5, further, the tachometer magnet 111 is fixed on the tachometer shaft 11, and the tachometer magnet 111 and the sensing electrode 123 are radially disposed; the speed measuring magnet 111 can generate a magnetic field and magnetic induction lines in different directions; it can be understood that the speed measuring shaft 11 bears the speed measuring magnet 111 to rotate, so that the direction of the magnetic induction line of the speed measuring magnet 111 is constantly changed; when the tachometer magnet 111 and the sensing electrode 123 are radially distributed, the tachometer magnet 111 generates a magnetic induction line connecting the sensing electrode 123 and the conductive coating 122. Meanwhile, it should be noted that the magnetic fluid includes a ferrofluid, non-magnetic conductive particles and a base fluid, and the ferrofluid and the non-magnetic conductive particles are uniformly distributed in the base fluid; it is known that the ferrofluid and the base fluid are insulators. Further, the non-magnetic conductive particles are self-assembled along the magnetic induction line direction under the action of the magnetic field of the speed measuring magnet to form a chain structure, and the non-magnetic conductive particles of the chain structure can realize the electric conduction between the induction electrode 123 and the conductive coating 122, so that the circuit can be closed and opened by changing the state of the magnetic fluid through controlling the magnetic field, and further the non-contact magnetic fluid rotating speed measuring device 10 outputs a current pulse signal.
Specifically, when the tachometer magnet 111 and the induction electrode 123 are radially distributed, the tachometer magnet 111 generates a magnetic induction line connecting the induction electrode 123 and the conductive coating 122, so that the non-magnetic conductive particles are connected to the induction electrode 123 and the conductive coating 122 in a chained manner, and are further electrically conducted to the induction electrode 123 and the conductive coating 122, so that the non-contact type magnetic fluid rotation speed measuring device 10 outputs a current pulse signal through the measurement; meanwhile, the speed measuring shaft 11 is connected with the rotating output end of the object to be measured, and the speed measuring magnet 111 rotates continuously, namely the direction of the magnetic induction line of the speed measuring magnet 111 is also changed continuously; further, when the tachometer magnet 111 and the sensing electrode 123 are radially distributed, a magnetic induction line connecting the conductive coating 122 and the sensing electrode 123 is generated, that is, the non-magnetic conductive particles are linked to the sensing electrode 123 and the conductive coating 122, the sensing electrode 123 and the conductive coating 122 are electrically conducted once, the non-contact magnetic fluid rotation speed measuring device 10 outputs a current pulse signal, and then the number of current pulse information can be detected to measure the number of rotation turns of the rotation output end of the object to be measured. It should be noted that, current detection circuit is prior art, and it only needs to detect that there is the electric current to appear can, the utility model discloses only do the application, and do not aim at current detection circuit does specifically and restricts.
With reference to fig. 4, further, the tachometer sleeve 12 is configured as a hollow cylinder, the tachometer cavity 121 has a first inner surface 125 close to the tachometer shaft 11 and a second inner surface 126 relatively far away from the tachometer shaft 11, the conductive coating 122 is disposed on the first inner surface 125, the second inner surface 126 is provided with an induction electrode ring (not shown), the induction electrodes 123 are disposed on the induction electrode ring at intervals, the conductive coating 122 is coated on all the first inner surfaces 125, and the magnetic fluid is filled between the induction electrodes 123 and the conductive coating 122. It can be understood that the number of the induction electrodes 123 is one or more, when the number of the induction electrodes 123 is multiple, the induction electrodes 123 are uniformly distributed on the induction electrode ring, the speed measuring shaft 11 bears the speed measuring magnet 111 and rotates for a circle, so that the magnetic fluid can sequentially electrically conduct the induction electrodes 123 and the conductive coating 122, and further the non-contact magnetic fluid rotating speed measuring device 10 outputs current pulse signals equal to the number of the induction electrodes 123, and further the non-contact magnetic fluid rotating speed measuring device 10 can complete accurate measurement of the rotating speed of the object to be measured under the condition of no load, thereby effectively improving the stability and safety of the rotating speed measurement.
In one embodiment, the induction electrode ring is prepared from a high polymer material and an insulating hard plastic; specifically, firstly, the surface of the polymer material is plated with the induction electrode 123 and a circuit, and then the induction electrode 123 and the circuit are sealed, bent and attached to the inner surface of the annular fixing piece made of the insulating hard plastic, the circuit is connected with the output end of the test current, so that the current on the induction electrode 123 is timely output, and a current pulse signal is generated.
It should be noted that the test sensing electrode ring can also be used to adjust the size of the gap of the cavity 121, that is, the sensing electrode ring can also be used to adjust the size of the gap between the sensing electrode 123 and the conductive coating 122; it can be understood that magnetic fluid is filled in the gap of the tachometer cavity 121, and the size of the gap between the induction electrode 123 and the conductive coating 122 is 50-100 μm; therefore, the size of the gap between the sensing electrode 123 and the conductive coating 122 is in a negative correlation with the rotating speed of the object to be measured; namely, the larger the rotating speed of the object to be measured is, the smaller the gap between the induction electrode 123 and the conductive coating 122 is; meanwhile, the smaller the rotating speed of the object to be measured is, the larger the gap between the induction electrode 123 and the conductive coating 122 is; of course, when the rotating speed of the object to be measured is small, the gap between the sensing electrode 123 and the conductive coating 122 may also be set to be small. And then the gap between the induction electrode 123 and the conductive coating 122 is adjusted through the induction electrode ring, so that the non-contact type magnetic fluid rotating speed measuring device 10 can accurately measure the rotating speeds of objects with different rotating speeds, and the measuring stability of the non-contact type magnetic fluid rotating speed measuring device 10 is improved.
Preferably, the non-contact magnetic fluid rotation speed measuring device 10 further includes a base 13, one end of the velocity measuring sleeve 12 is integrally connected to the base 13, an opening (not shown) is disposed at one end of the velocity measuring sleeve 12 away from the base 13, a sealing end cover 14 is disposed at one end of the velocity measuring sleeve 12 away from the base 13, and the sealing end cover 14 is annular; namely, one end of the speed measuring cavity 121 is sealed by the base, and the other end is sealed by the sealing end cap 14; by arranging the sealing end cover 14, the magnetofluid solution in the speed measuring cavity 121 can be replaced and filled, and the speed measuring sleeve 12 is convenient to maintain. It should be noted that the base 13 is made of a non-magnetic material, so as to effectively avoid interference with the magnetic field distribution of the speed measurement magnet 111 in the speed measurement cavity 121, and effectively increase the speed measurement stability and accuracy of the non-contact magnetic fluid rotation speed measurement device 10.
Preferably, a permanent magnet 15 is further disposed between the tachometer sleeve 12 and the end cap 14, near the first inner surface 125. The permanent magnet 15 is used for assisting the end cover 14 to seal the magnetic fluid in the speed measuring cavity 121, so as to prevent the magnetic fluid from leaking.
Preferably, the non-contact magnetic fluid rotation speed measuring device 10 further includes a rotor 16, the rotor 16 is disposed between the tachometer shaft 11 and the tachometer sleeve 12, the rotor 16 is fixed on the tachometer shaft 11, a gap is disposed between the rotor 16 and the tachometer sleeve 12, and the tachometer magnet 111 is disposed on a surface of the rotor 16 facing the tachometer sleeve 12. Further, the rotor 16 is arranged in a circular ring shape, and the inner diameter of the rotor 16 is matched with the outer diameter of the speed measuring shaft 11; one end of the rotor 16 is fixed on one end of the speed measuring shaft 11 through a fixed key 19.
Specifically, a first key position sinking groove (not shown) is formed on the surface of the rotor 16, which is in contact with the speed measuring shaft 11, a second key position sinking groove (not shown) is correspondingly formed on the speed measuring shaft 11, and the fixing key 19 is accommodated in the first key position sinking groove and the second key position sinking groove; it can be understood that the rotor 16 can be fixed to the tachometer shaft 11 by providing a fixing key 19; meanwhile, the replacement and maintenance of the rotor 16 or the tachometer shaft 11 can also be realized.
Furthermore, a rotor sinking groove (not shown) is formed on a surface of the rotor 16 facing the speed measuring sleeve 12, the speed measuring magnet 111 is fixed on the rotor sinking groove through a fixing slider 18, and the fixing slider 18 and the rotor 16 are fixed in a threaded manner. It should be noted that the rotor 16 is fixed in contact with the tachometer shaft 11, and the rotor 16 is not in contact with the tachometer sleeve 12; further, the speed measuring load of the speed measuring shaft 11 is effectively reduced, and the safety of the non-contact magnetic fluid speed measuring device in measuring the rotating speed is improved.
Preferably, a shaft end baffle 17 is arranged at the connecting end of the rotor 16 and the speed measuring shaft 11. Namely, the rotor 16 and one end of the speed measuring shaft 11, which is far away from the object to be measured, are sealed by the shaft end baffle 17; the shaft end baffle 17 is a circular plate and is fixed on the rotor 16 through a bolt, and the interference of dust on the rotor 16 and the speed measuring shaft 11 can be effectively avoided by arranging the shaft end baffle 17, so that the application range of the non-contact magnetic fluid rotating speed measuring device 10 is expanded.
Further, the rotating speed measuring method based on the non-contact magnetic fluid rotating speed measuring device is used for measuring the rotating speed of an object to be measured, and comprises the following steps:
connecting the rotating speed output end of the object to be measured with the speed measuring shaft of the non-contact magnetic fluid rotating speed measuring device of the utility model;
after an object to be detected is started, the rotating speed R = N/(m multiplied by T) of the object to be detected, wherein N is the number of current pulse signals received by the current detection circuit within a time period T; and m is the number of the induction electrodes.
Still further based on the utility model provides a design method of non-contact magnetic current body rotational speed measuring device, it includes:
selecting the kind of magnetic fluid.
Specifically, the magnetic fluid mainly comprises non-magnetic conductive particles, ferrofluid and base fluid; wherein the particle size of the non-magnetic conductive particles is set to be micro-scale or nano-scale; selecting ferrofluid as base fluid according to the physical and chemical properties of the nonmagnetic conductive particles; wherein the ferrofluid is an insulator, and the non-magnetic conductive particles are uniformly dispersed and suspended in the ferrofluid. Furthermore, the ferrofluid is temperature-sensing insulating ferrofluid with good heat dissipation performance; the base liquid can be prepared by selecting solvents such as water, engine oil, hydroxyl oil and the like; and the self-assembly efficiency of the nonmagnetic conductive particles assembled into the chain with the length L under the designed magnetic field strength reaches 70 percent.
And designing components of the non-contact magnetic fluid rotating speed measuring device according to the rotating speed output end of the object to be measured and the rotating speed measuring environment.
Specifically, whether the rotating speed output end of the object to be measured has the conditions of magnetism, shaft diameter size, rotating speed range, measuring environment and the like or not is determined, and components of a speed measuring sleeve, a speed measuring shaft, a key, a shaft end baffle speed measuring magnet, a magnet stop block with a threaded hole and the like of the non-contact type magnetic fluid rotating speed measuring device are designed.
And designing the number m of the induction electrodes according to the width and rotating speed measurement requirements of the speed measuring magnet.
The base is designed according to the installation environment and the position size, the conductive coating is sprayed on the bottom of the speed measuring cavity, the sensing electrode ring is installed, the coaxiality of the base and the sensing electrode ring is checked, and the actual effective gap of the speed measuring cavity is adjusted through the thickness of the sensing electrode ring fixing piece.
Specifically, the actual effective gap of the velocity measurement cavity, that is, the gap between the sensing electrode and the conductive coating, should be smaller than the length of the chain formed by assembling the nonmagnetic conductive particles under the magnetic field strength. Further, the gap between the induction electrode and the conductive coating is defined as L1Defining the length of the chain assembled by the non-magnetic conductive particles under the magnetic field intensity as L2Then said L2/4<L1<L2。
Designing a sealing end cover according to the size of a base, designing an end cover sealing permanent magnet installation groove on the sealing end cover, installing a sealing permanent magnet, filling the prepared ferrofluid mixed with the non-magnetic conductive particles into a speed measuring cavity, and testing the anti-leakage characteristic of the speed measuring cavity.
Furthermore, a gap of 0.02-0.20mm needs to be reserved between the sealing permanent magnet and the speed measuring sleeve.
The rotor provided with the speed measuring magnet and the magnet stop block with the threaded hole is connected with the shaft end baffle through keys, is arranged on the speed measuring shaft, and is arranged at a test position corresponding to the induction electrode ring.
After the initial assembly, an electrification test experiment is required, and the effectiveness of the assembly is ensured.
Compared with the prior art, the utility model provides a non-contact magnetic fluid rotating speed measuring device; the non-contact magnetic fluid rotating speed measuring device measures the rotating speed of an object to be measured through an external current detection circuit, and comprises: the device comprises a speed measuring shaft and a speed measuring sleeve which are coaxially arranged, wherein the speed measuring sleeve is sleeved on the speed measuring shaft, and a gap is formed between the speed measuring shafts; the speed measuring sleeve is provided with a speed measuring cavity, a conductive coating, an induction electrode and a magnetic fluid are arranged in the speed measuring cavity, and the conductive coating and the induction electrode are externally connected with a current detection circuit and are coaxially arranged with the speed measuring shaft; a speed measuring magnet is fixed on the speed measuring shaft, and the speed measuring magnet and the induction electrode are arranged in the same radial direction; the speed measuring shaft is used for being connected with the rotating speed output end of the object to be measured and synchronously driving the speed measuring magnet to rotate. Therefore, the speed measuring load of the speed measuring shaft is effectively reduced, and the safety, the stability and the application range of the speed measuring shaft are improved.
It is to be understood that the invention is not limited to the above-described embodiments, and that modifications and variations may be made by those skilled in the art in light of the above teachings, and all such modifications and variations are intended to be included within the scope of the invention as defined in the appended claims.
Claims (10)
1. The utility model provides a non-contact magnetic current body rotational speed measuring device, measures the object rotational speed that awaits measuring through external current detection circuit, its characterized in that includes:
the device comprises a speed measuring shaft and a speed measuring sleeve which are coaxially arranged, wherein the speed measuring sleeve is sleeved on the speed measuring shaft, and a gap is formed between the speed measuring shafts;
the speed measuring sleeve is provided with a speed measuring cavity, a conductive coating, an induction electrode and a magnetic fluid are arranged in the speed measuring cavity, and the conductive coating and the induction electrode are externally connected with a current detection circuit and are coaxially arranged with the speed measuring shaft;
a speed measuring magnet is fixed on the speed measuring shaft, and the speed measuring magnet and the induction electrode are arranged in the same radial direction;
the speed measuring shaft is used for connecting the rotating speed output end of the object to be measured and synchronously driving the speed measuring magnet to rotate.
2. The non-contact magnetic fluid rotation speed measuring device according to claim 1, further comprising an induction electrode ring, wherein the induction electrode ring is fixed on a surface of the speed measuring cavity far away from the speed measuring shaft, and induction electrodes are arranged on the induction electrode ring at intervals.
3. The non-contact magnetic fluid speed measurement device according to claim 2, wherein the tachometer sleeve is configured as a hollow cylinder, the tachometer cavity has a first inner surface close to the tachometer shaft and a second inner surface relatively far from the tachometer shaft, the conductive coating is disposed on the first inner surface, and the induction electrode ring is disposed on the second inner surface.
4. The non-contact magnetic fluid rotation speed measuring device according to claim 3, further comprising a base, wherein one end of the speed measuring sleeve is integrally connected with the base.
5. The non-contact magnetic fluid rotation speed measuring device according to claim 4, wherein a sealing end cover is arranged at one end of the speed measuring sleeve, which is far away from the base, and the sealing end cover is arranged in a ring shape.
6. The non-contact magnetic fluid rotation speed measuring device according to claim 5, wherein a permanent magnet is further arranged between the speed measuring sleeve and the sealing end cover and close to the first inner surface.
7. The non-contact magnetic fluid rotation speed measuring device according to any one of claims 1 to 6, further comprising a rotor, wherein the rotor is disposed between the tachometer shaft and the tachometer sleeve, the rotor is fixed on the tachometer shaft with a gap therebetween, and the tachometer magnet is disposed on a surface of the rotor facing the tachometer sleeve.
8. The non-contact magnetic fluid rotation speed measuring device according to claim 7, wherein a rotor sinking groove is formed in a surface of the rotor facing the speed measuring sleeve, the speed measuring magnet is fixed to the rotor sinking groove through a fixing slider, and the fixing slider is fixed to the rotor in a threaded manner.
9. The non-contact magnetic fluid rotation speed measuring device according to claim 8, wherein a shaft end baffle is arranged at the connecting end of the rotor and the speed measuring shaft.
10. The non-contact magnetic fluid rotation speed measuring device according to any one of claims 8 to 9, wherein the rotor is detachably and fixedly connected with the speed measuring shaft through a fixed key; the rotor is provided with a first key position sinking groove on the surface contacting with the speed measuring shaft, the speed measuring shaft is correspondingly provided with a second key position sinking groove, and the fixed key is accommodated in the first key position sinking groove and the second key position sinking groove.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201920783047.8U CN209946192U (en) | 2019-05-28 | 2019-05-28 | Non-contact magnetic fluid rotating speed measuring device |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201920783047.8U CN209946192U (en) | 2019-05-28 | 2019-05-28 | Non-contact magnetic fluid rotating speed measuring device |
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| CN209946192U true CN209946192U (en) | 2020-01-14 |
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| CN201920783047.8U Expired - Fee Related CN209946192U (en) | 2019-05-28 | 2019-05-28 | Non-contact magnetic fluid rotating speed measuring device |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2020238402A1 (en) * | 2019-05-28 | 2020-12-03 | 南方科技大学 | Non-contact magnetic fluid rotational speed measuring device, design method and rotational speed measuring method |
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2019
- 2019-05-28 CN CN201920783047.8U patent/CN209946192U/en not_active Expired - Fee Related
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2020238402A1 (en) * | 2019-05-28 | 2020-12-03 | 南方科技大学 | Non-contact magnetic fluid rotational speed measuring device, design method and rotational speed measuring method |
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