CN201159631Y - Detection apparatus for hydraulic support linear displacement transducer - Google Patents
Detection apparatus for hydraulic support linear displacement transducer Download PDFInfo
- Publication number
- CN201159631Y CN201159631Y CNU200820092633XU CN200820092633U CN201159631Y CN 201159631 Y CN201159631 Y CN 201159631Y CN U200820092633X U CNU200820092633X U CN U200820092633XU CN 200820092633 U CN200820092633 U CN 200820092633U CN 201159631 Y CN201159631 Y CN 201159631Y
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- Prior art keywords
- displacement transducer
- linear displacement
- magnetic
- hydraulic support
- tongue tube
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Abstract
The utility model relates to a linear displacement detecting sensor for detecting the linear displacement of a hydraulic bracket. The linear displacement detecting sensor comprises an excitation mechanism and a displacement detecting sensor main body; wherein the excitation mechanism is composed of a horizontal excitation unit which is capable of magnetic extrusion and a vertical extrusion unit which is capable of preventing horizontal magnetic leakage; the displacement detecting sensor main body is composed of a constant power supply circuit, a dry reed pipe detection circuit and a signal filter circuit. The current that the linear displacement detecting sensor needs when detecting the displacement runs through the displacement detecting sensor main body which is constituted by the dry reed pipe detection circuit and excites only one dry reed pipe at certain place to be pulled on through the displacement of the external excitation mechanism to generate detection voltage; then the detection voltage generates, through the filter circuit, noise-eliminating voltage signal which can be connected to the main control unit of the hydraulic bracket. The linear displacement detecting sensor is high in detecting sensitivity and precision. Adopting an active resistance-capacitance low-pass network, the linear displacement detecting sensor is improved in shake resistance.
Description
Technical field
The utility model relates to detection technique, is specifically related to a kind ofly be suitable for mining industry and combine and to adopt in the high vibration environment of operation, and the hydraulic support linear displacement transducer detection device with higher detection precision, sensitivity and high vibration resistance.
Background technology
Hydraulic support electrohydraulic control system is to begin research and development in the seventies in last century the earliest, just enter practical stage the eighties, to the nineties, the hydraulic support electrohydraulic control system technology is ripe, serviceability and reliability can satisfy the operation technique requirement, the hydraulic support sensor is also along with development of technology, and its serviceability and reliability are also constantly perfect.
Classical electromagnetic potential displacement sensor stage (Jiang Xiaoxia has been experienced in the development of displacement transducer, Zhong Ronglong, Lu Changgeng. the application of magnetostrictive displacement sensor. sensor technology .2003, (1): 50-52) with semiconductor displacement transducer developing stage (Yu Yanguang, Sun Xiaoming, Wei Zhenlu etc. the modelling of semiconductor laser tube displacement transducer and simulation analysis. optical technology .1999, (3): 11-13).
The novel sensor of based semiconductor photoelectric characteristic (Huang Wei, Zhou Zhaofei open great waves. the research of integrated electro sensor.Laser technology .2004,28 (6): 596-597), they are information carrier with the light beam, have advantages such as noncontact, high precision, caused the displacement transducer technology revolution, measurement is developed to the noncontact direction, jump onto a new step, formed the important branch of modern sensor technology and subject.
Detect occasion at high precision displacement, generally adopt grating to carry out displacement detecting.For example: the displacement detecting of the elevator device cab of Mitsubishi is used photoelectric encoder; The endless loop pneumatic system of the band displacement detecting of FESTO company is used potentiometric displacement transducer (Liu Qin, Ma Fengming, Liu Ming. differential variable pressure transducer displacement measurement system design. Tianjin Enginnering Normal College's journal .2005,15 (3): 50～53), the differential type inductance displacement sensor is adopted in the detection of the medium and small displacement of product of BOST company.
The patent No. of Siemens Company's application is 02808461.6, the work range that name is called passive this sensor of magnetic position sensor only has several centimetres, thereby adopt the adhesive of magnetic magnetization magnetic sheet to constitute resistance loop and come the detection position, this utility model has proposed the improved passive magnetic position sensor of a kind of magnetive attraction to permanent magnetism in order to improve accuracy of detection.
The patent No. of Amada Co., Ltd.'s JP-6301 application is 200510054876.5, and name is called to be used the magnetic Hall element and detect displacement because of magnet assembly in the utility model patent of displacement transducer.
The patent No. of Japan Servo application is to adopt a kind of Hall element that the variation of magnetic flux is converted into voltage output in 200510004137 utility model patents that are called magnetic linear position sensor, and the range of linearity of detection is 10mm.
The patent No. of Amada Co., Ltd.'s JP-6301 application is 200510054876.5, and name is called to be used the magnetic Hall element and detect displacement because of magnet assembly in the utility model patent of displacement transducer.
The patent No. of Nanjing Aero-Space University application is 200510040268, and the magnetic flux density that name is called breath place between the survey sensor and testee in the utility model patent of magnetic displacement sensor obtains the range information between measured object and the sensor.
The above these patent or document all do not provide the linear displacement transducer device technique that is applicable to hydraulic bracket system, though the displacement transducer of Amada Co., Ltd.'s JP-6301 application can be suitable for the occasion of wide range, but because displacement transducer is to expose under industrial and mineral in the hydraulic bracket system, so the installation of this patented technology and principle of work and be not suitable in the hydraulic bracket system.
The utility model content
In order to solve can not providing a kind of and effectively providing this technical matters of linear displacement transducer device technique that is applicable to hydraulic bracket system of existing in the prior art, the utility model provides a kind of and has been suitable for mining industry and combines and to adopt in the high vibration environment of operation, and the hydraulic support linear displacement transducer detection device with higher detection precision, sensitivity and high vibration resistance.
The technical scheme that the prior art problem that solves the utility model is adopted is: a kind of hydraulic support linear displacement transducer device is provided, described pressure support linear displacement transducer device comprises that excitation mechanism, displacement transducer detect body, wherein, described excitation mechanism comprises the vertical magnetic cell of squeezing with waterproof flat leakage magnetic in the crowded horizontal excitation of magnetic unit; Described displacement transducer detects body and comprises constant-current source circuit, tongue tube testing circuit and signal filter circuit; The described hydraulic support linear displacement transducer device detection body that required electric current is flowed through and is made up of described tongue tube testing circuit of finding range, the unique adhesive of displacement excitation somewhere tongue tube by described external excitation mechanism, generate and detect voltage, described detection voltage obtains connecing the de-noising voltage signal of putting hydraulic support electricity liquid master control system unit by described filtering circuit.
According to a preferred embodiment of the present utility model: described excitation mechanism adopts two pairs of magnet peers to generate the horizontal excitation of the described crowded magnetic unit that strengthens magnetic circuit directive property, magnetic field intensity to squeezing.
According to a preferred embodiment of the present utility model: described magnet is a horseshoe type.
According to a preferred embodiment of the present utility model: in described horse-shoe magnet both sides to accompanying axial excitation magnet ring.
According to a preferred embodiment of the present utility model: described displacement transducer detects body and adopts tongue tube as magnetic switch.
According to a preferred embodiment of the present utility model: the equidistant discharging of described tongue tube also links to each other with power supply.
According to a preferred embodiment of the present utility model: the magnetic circuit that the horizontal excitation of described crowded magnetic unit produces is a zero degree with the angle of described tongue tube, and the angle that described waterproof flat leakage magnetic vertically squeezes axial energized circuit in the magnetic cell and described tongue tube is 90 to spend.
According to a preferred embodiment of the present utility model: described displacement transducer detects body and adopts casting glue formula structure.
The utility model hydraulic support linear displacement transducer device has been broken away from the dependence that comprehensively needs import to the displacement measurement unit of hydraulic support control system, adopt tongue tube to finish the demand of wide range range finding as the magnetic switch that detects, and utilize the change of external excitation cellular construction according to tongue tube adhesive principle of work, sensitivity of linear displacement transducer Device Testing and measuring accuracy have been improved, reduced the time of producing simultaneously with processing, by adopting active capacitance-resistance low-pass network, improved the anti-seismic performance of the utility model linear displacement transducer device.
Description of drawings
Fig. 1. the corresponding relation structural representation that the inner tongue tube of the utility model hydraulic support linear displacement transducer device cathetus displacement transducer pick-up unit links to each other with power supply;
Fig. 2. tongue tube and horizontal magnetic force lineman make the coordinate synoptic diagram;
Fig. 3. tongue tube and vertical magnetic line of force work coordinate synoptic diagram;
Fig. 4. the horseshoe magnet structural representation;
Fig. 5. the cross-sectional view of external excitation magnet ring;
Fig. 6. horseshoe magnet section magnetic circuit H analyzes synoptic diagram;
Fig. 7. external excitation magnet ring magnetic circuit H analyzes synoptic diagram;
Fig. 8. external excitation mechanism structural representation;
Fig. 9. displacement transducer shell mechanism synoptic diagram;
Figure 10. the utility model hydraulic support linear displacement transducer detection device structural representation;
Figure 11. strong motion situation bottom offset sensor end output waveform synoptic diagram;
Figure 12. the constant-current source circuit schematic diagram;
Figure 13. tongue tube testing circuit schematic diagram;
Figure 14. active capacitance-resistance low-pass network filtering circuit schematic diagram.
Embodiment:
Below in conjunction with accompanying drawing and concrete embodiment the utility model is done explanation in further detail:
The purpose of this utility model is that the discrete feature at tongue tube PI value changes the magnetic force loop of external excitation mechanism 101, improves the precision that detects.
In order to satisfy the wide range range finding, to combine the high measurement accuracy of adopting antidetonation demand and hydraulic bracket system cathetus displacement sensing, the utility model provides a kind of wide range, high precision, high shock resistance linear displacement transducer device device, this device can not only guarantee that measuring hydraulic support at high vibration environment pushes away and saunter and draw the slide rectilinear path, and can satisfy distance accuracy and approximate 4mm, this device processing simultaneously is simple, is suitable for producing in batches.
For realizing above-mentioned utility model purpose, hydraulic support linear displacement transducer device provided by the utility model, comprise that excitation mechanism 101, displacement transducer detect body 102, wherein, described excitation mechanism 101 comprises the vertical magnetic cell of squeezing with waterproof flat leakage magnetic in the crowded horizontal excitation of magnetic unit; Described displacement transducer detects body 102 and comprises constant-current source circuit 103, tongue tube testing circuit 104 and signal filter circuit 105; The described hydraulic support linear displacement transducer device detection body that required electric current is flowed through and is made up of described tongue tube testing circuit 104 of finding range, displacement excitation somewhere tongue tube 106 unique adhesives by described external excitation mechanism 101, generate and detect voltage, described detection voltage obtains connecing the de-noising voltage signal of putting hydraulic support electricity liquid master control system unit by described filtering circuit 105.
The principle of work of the utility model displacement sensor device is to change displacement into resistance change, the variation of resistance value is that the principle of using tongue tube 106 conducting under certain magnetic field intensity realizes, the constant current source drive current produces pressure drop on pull-up resistor, realize by the voltage that detects the pull-up resistor two ends, make displacement and to detect voltage linear.The design of range finding body is to adopt tongue tube 106 as magnetic switch, by made tongue tube 106 adhesives at current displacement place by custom-designed outside excitation loop, generates and the corresponding magnitude of voltage of this displacement thus.Therefore move or perhaps the body circuit of finding range can detect output terminal output and the corresponding voltage of this displacement when moving when outside excitation loop.
The utility model hydraulic support linear displacement transducer Device Testing method is: change displacement into resistance change, the variation of described resistance value is to use the principle of tongue tube 106 conducting under certain magnetic field intensity to realize, the constant current source drive current produces pressure drop on pull-up resistor, realize by the voltage that detects the pull-up resistor two ends, make displacement linear with detection voltage.Described detection method specifically comprises step: one, described excitation mechanism 101 is detected body 102 relative to described displacement transducer and move; Two, the displacement increase being changed into corresponding pull-up resistor increases; Three, detect the voltage at described pull-up resistor two ends; Four, the corresponding relation according to described pull-up resistor both end voltage and described displacement obtains shift length.The utility model hydraulic support linear displacement transducer apparatus structure synoptic diagram can be consulted Figure 10.
The excitation mechanism 101 of the utility model patent adopts two pairs of horse-shoe magnet 107 peers to generate the enhancement mode magnetic excitation circuit to squeezing, as shown in Figures 4 and 5.For preventing that the air gap magnetic circuit that leaks from causing having simultaneously two tongue tubes, 106 adhesive situations, this to squeeze horse-shoe magnet 107 both sides to folder on two plain shafts to excitation magnet ring 108, these two magnet rings can stop the air gap of water chestnut magnet 107 magnetic circuit that leaks.The shape of a hoof in the utility model linear displacement transducer device is a zero degree to squeezing the magnetic circuit and tongue tube 106 angles that produce, axial energized circuit in the device and tongue tube 106 angles are 90 degree, and magnetic circuit and tongue tube 106 angles are that 90 tongue tubes 106 when spending are not worked as can be known by the principle of work of tongue tube 106.Therefore this device satisfied when external energized circuit only be the tongue tube 106 adhesive work of correspondence with it during in certain.
The anti-seismic performance of this device of detection filter circuit 105 designs can the raising of this utility model distance measuring equipment, adopt the filtering circuit 105 of active capacitance-resistance low-pass network as this device, described active capacitance-resistance low-pass network filtering circuit schematic diagram can be consulted Figure 14, selected in the present embodiment amplifier model is LM258, resistance is 560K Europe, electric capacity is 0.1uF, and it is the noise bandwidth decision that leaches as required that RC is worth selecting.The frequency that records this vibrations noise during actual ore deposit is tested down is greater than 20Hz, the timeconstant=0.56s of this filtering circuit 105, and this value can leach the vibrations noise greater than 17.8Hz.
When a strength of current is that I constant current source drive current is arranged series load resistance by one, be connected to tongue tube 106 between the resistance, tongue tube 106 equidistantly discharging links to each other with power supply 109.When magnet ring passed through on sensor, tongue tube 106 was with regard to conducting, and corresponding pull-up resistor increases, and detects the voltage in the load, just can determine the displacement of magnet ring on sensor as shown in Figure 1.After A moved N tongue tube 106 spacings, the B point was R to the resistance of conducting tongue tube 106 to magnet ring from the B point
x: R
X=(N-1) R+R
0
Fig. 2 has provided tongue tube 106 and concerned coordinate in the position of adhesive and shutoff under the horizontal magnetic force line, by analyzing this coordinate, the design horseshoe magnet as shown in Figure 4 external excitation magnet ring 108.Range finding direction and Fig. 2 of this utility model patent, the X-direction unanimity of Fig. 3.Fig. 5 has provided tongue tube 106 and concerned coordinate in the position of adhesive and shutoff under the vertical magnetic line of force, by analyzing this coordinate, designed external excitation unit as Fig. 8, the fundamental purpose of this device is in order to stop 107 pairs of water chestnut magnets to squeeze air gaps that the back the generates magnetic circuit that leaks, and magnetic circuit can cause when a certain position not only error that tongue tube 106 adhesive work bring thereby this leaks.Fig. 6 is that horseshoe magnet cuts open magnetic circuit H analysis chart, this figure is the vertical view of shape of a hoof magnet ring, this figure can clearly see the magnetic circuit that leaks, Fig. 7 is external excitation magnet ring 108 magnetic circuit H analysis charts, by analyzing this figure, the magnetic circuit that this excitation unit can satisfy level only is present in the shape of a hoof magnet ring, therefore when the excitation unit is in certain, can only convey its corresponding tongue tube 106 adhesive work.
Fig. 8 is external excitation mechanism 101 entity structure synoptic diagram, and excitation magnet ring 108 is by magnet ring shell 110 parcels in Fig. 8.Fig. 9 is this utility model device displacement transducer steel body case structural representation, Figure 10 is the hydraulic support linear displacement transducer apparatus structure synoptic diagram behind the casting glue, external excitation mechanism 101 is enclosed within outside this displacement transducer solid element during detection, move horizontally external excitation mechanism 101, just can obtain the detection voltage waveform of 0.5V to 4.5V as shown in figure 11 at output terminal, among the figure 111 for sealing, 112 be that tongue tube testing circuit plate, 113 is the output connection head.
Constant-current source circuit 103 schematic diagrams can be consulted Figure 12 in the utility model, and this circuit input 12V voltage is output as the 0.1667mA electric current as shown in figure 12.Two diodes of power supply 109 input ends constitute safety barrier, and diode is selected 1N5822 for use, and 1N5822 is a low-power consumption, high-level efficiency, and the diode component that current carrying capacity is strong has the instantaneous protection function, and it is encapsulated as DO-201AD.Connect a current-limiting resistance after the safety barrier and remove lotus root electric capacity, C
1, C
2Be respectively 4.7 μ F, 0.01 μ F.Be the output of constant current source at last, the three end constant-current source devices of selecting for use are LM234, and the input voltage range of this device is 1～40V, and output current value is by a non-essential resistance R
1=750 Ω set, and do not need other settings, and its output current precision is 3%, the electric current adjustable extent is 1 μ A～10mA, its temperature coefficient of constant current source that single outer meeting resistance constitutes is bad, electric current with variation of temperature satisfy 0.33%/℃, suppress temperature and float and need add a resistance R
2=7.5K Ω and diode model be 1N457 as shown in the figure because this model diode does not have at present, select general-purpose diode 1N4148 for use, when an external 27K Ω load, load voltage is 4.501V, meets the demands.As shown in figure 12, electric current:
The utility model hydraulic support linear displacement transducer device has been broken away from the dependence that comprehensively needs import to the displacement measurement unit of hydraulic support control system, adopt tongue tube 106 to finish the demand of wide range range finding as the magnetic switch that detects, and utilize the change of external excitation cellular construction according to tongue tube 106 adhesive principle of work, sensitivity of linear displacement transducer Device Testing and measuring accuracy have been improved, reduced the time of producing simultaneously with processing, by adopting active capacitance-resistance low-pass network, improved the anti-seismic performance of the utility model linear displacement transducer device.
Above content be in conjunction with concrete preferred implementation to further describing that the utility model is done, can not assert that concrete enforcement of the present utility model is confined to these explanations.For the utility model person of an ordinary skill in the technical field, under the prerequisite that does not break away from the utility model design, can also make some deduction or replace, all should be considered as belonging to protection domain of the present utility model.
Claims (8)
1. a hydraulic support linear displacement transducer detection device comprises excitation mechanism (101), displacement transducer detection body (102), it is characterized in that: described excitation mechanism (101) comprises the vertical magnetic cell of squeezing with waterproof flat leakage magnetic in the crowded horizontal excitation of magnetic unit; Described displacement transducer detects body (102) and comprises constant-current source circuit (103), tongue tube (106) testing circuit (104) and signal filter circuit (105); The described hydraulic support linear displacement transducer device detection body that required electric current is flowed through and is made up of described tongue tube testing circuit (104) of finding range, the unique adhesive of displacement excitation somewhere tongue tube (106) by described external excitation mechanism (101), generate and detect voltage, described detection voltage obtains connecing the de-noising voltage signal of putting hydraulic support electricity liquid master control system unit by described filtering circuit (105).
2. according to the described hydraulic support linear displacement transducer detection device of claim 1, it is characterized in that: described excitation mechanism (101) adopts two pairs of magnets (107) at the same level to squeezing the horizontal excitation of the described crowded magnetic unit that generates enhancing magnetic circuit directive property, magnetic field intensity.
3. according to the described hydraulic support linear displacement transducer detection device of claim 2, it is characterized in that: described magnet (107) is a horseshoe type.
4. according to claim 2 or 3 described hydraulic support linear displacement transducer detection devices, it is characterized in that: in described horse-shoe magnet (107) both sides to accompanying axial excitation magnet ring (108).
5. according to the described hydraulic support linear displacement transducer detection device of claim 1, it is characterized in that: described displacement transducer detects body (102) and adopts tongue tube (106) as magnetic switch.
6. according to the described hydraulic support linear displacement transducer detection device of claim 1, it is characterized in that: the equidistant discharging of described tongue tube (106) also links to each other with power supply (109).
7. according to the described hydraulic support linear displacement transducer detection device of claim 1, it is characterized in that: the magnetic circuit that the horizontal excitation of described crowded magnetic unit produces and the angle of described tongue tube (106) are zero degree, and the axial energized circuit in the vertically crowded magnetic cell of described waterproof flat leakage magnetic and the angle of described tongue tube (106) are 90 degree.
8. according to the described hydraulic support linear displacement transducer detection device of claim 1, it is characterized in that: described displacement transducer detects body (102) and adopts casting glue formula structure.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNU200820092633XU CN201159631Y (en) | 2008-03-07 | 2008-03-07 | Detection apparatus for hydraulic support linear displacement transducer |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNU200820092633XU CN201159631Y (en) | 2008-03-07 | 2008-03-07 | Detection apparatus for hydraulic support linear displacement transducer |
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| CN201159631Y true CN201159631Y (en) | 2008-12-03 |
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| CNU200820092633XU Expired - Lifetime CN201159631Y (en) | 2008-03-07 | 2008-03-07 | Detection apparatus for hydraulic support linear displacement transducer |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103410567A (en) * | 2013-08-27 | 2013-11-27 | 天津华宁电子有限公司 | Mine smoke sensor with self-checking function |
| CN109855519A (en) * | 2017-11-30 | 2019-06-07 | 中国科学院沈阳自动化研究所 | A kind of manned underwater vehicle non-contact compensation oil mass detection sensor device |
-
2008
- 2008-03-07 CN CNU200820092633XU patent/CN201159631Y/en not_active Expired - Lifetime
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103410567A (en) * | 2013-08-27 | 2013-11-27 | 天津华宁电子有限公司 | Mine smoke sensor with self-checking function |
| CN109855519A (en) * | 2017-11-30 | 2019-06-07 | 中国科学院沈阳自动化研究所 | A kind of manned underwater vehicle non-contact compensation oil mass detection sensor device |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| AV01 | Patent right actively abandoned |
Granted publication date: 20081203 Effective date of abandoning: 20080307 |