CN207965170U - A kind of detection device checking preceding human body metal material for MR - Google Patents

Abstract

The utility model is related to a kind of detection devices checking preceding human body metal material for MR, including：Control core microcontroller, metal object detector, stepper motor, photoelectric sensor, D/A converter, signal amplifier, audible-visual annunciator, large-screen display；Stepper motor controls the movement of metal object detector, the metal object detector, photoelectric sensor, D/A converter, signal amplifier, audible-visual annunciator, large-screen display are both connected on core microcontroller, audible-visual annunciator, large-screen display are both connected on signal amplifier, and entire detection device is powered using power supply module.The utility model can be quickly detected the presence of metal object and accurately provide specific location information, and can fundamentally avoid using the unnecessary injury caused by human body of x-ray detection mode.

Description

A kind of detection device checking preceding human body metal material for MR

Technical field

The utility model is related to a kind of detection devices of human metalloproteinase material, and in particular to a kind of to be quickly detected gold Belong to the presence of object and accurately provide specific location information, and what will not be damaged to human body checks preceding human body gold for MR Belong to the detection device of material.

Background technology

The medical detection method high as a noninvasive "dead" radiation damage diagnosis efficiency, magnetic resonance (MR) have, Energy unrestricted choice photography level, and can show the spatial distribution of reflection histoorgan metabolic function, physiology and Biochemical Information, to Achieve the purpose that a variety of diseases of diagnosis.Favored by more and more medical personnels and those who are investigated.Magnetic resonance (MR) structure of scanning machine can be divided into two large divisions by its function：(1) signal is generated, detects and is encoded；(2) data acquisition, place Reason and image show, store.It can generate powerful and uniform main field.Patient is placed in main field when inspection, by The coil that can generate radio-frequency pulse is placed at inspection position, and the second magnetic field is formed after energization.The frequency that coil generates radio-frequency pulse such as connects The metal material (coin, metal hanger, the underwear brassiere etc. made with metal material) that person of modern times's body carries in various ways draws Magnetic resonance imaging can be impacted by playing artifact：Metal material will produce electric current when human motion and displacement in MR checking processes And fever.Magnetization is will produce into the ferrimagnet (ferromagnetic materia1) behind magnetic field, and is occurred with magnetic field Effect, related with the ferromagnetic size of the field strength size and object of main field and gradient fields first, shape, matter secondly with object Amount, the position and direction of plane are in relation to being finally the length with imaging time.If metal implant is nonferromagnetic in human body , the either suffered deflecting force or attraction is smaller is not enough to cause object of which movement and displacement or magnetic force in magnetic field When interior fixed force when being implanted into less than metal, MR checks still safe and feasible.There is quite a few that can measure partially in oral cavity material Turn power, but wherein only has Magnetized Material (magnetically activateddevice) to be only MR and check taboo.Silver amalgam, Deflecting force is not present in silver-colored points etc..Cardiac replacement valve majority has ferromagnetism, can measure deflecting force, but the deflecting force is much smaller than heart The active force that beating applies valve, thus patient remains to receive MR inspections in most cases.Blood vessel internal filter and holder After being implanted into several weeks, once it is securely connect with vascular wall, it, will not be because of the powerful effect in magnetic field when checking even if there is ferromagnetism It falls off.Materials most is fixed in bone surgery to be made of nonmagnetic alloy, can equally receive MR inspections.And early stage Some can then seriously affect the effect of magnetic resonance imaging to reduce cost using the material that inferior stainless steel makes.However Ferromagnetic aneurysm clip and hemostatic clamp cannot then do MR inspections certainly.In addition artificial cochlea or intraocular have ferromagnetic material Patient can not do MR inspections.These metal materials cause artifact, also known as magnetic susceptibility artifact (magneticsusceptibility artifact).It, which shows as local signal, which loses around low signal, high RST ring, Frequency coding and select layer coding direction occur object form distortion.The reason is that：(1) cause local magnetic field uneven and spin proton Dephasing position, the frequency and phase anomaly of (2) spin proton cause space orientation mistake, and (3) metal material is encouraged in radio-frequency pulse Lower generation eddy current, it is uneven to will also result in local magnetic field, and this effect is relatively weak, but nonferromugnetic material generate it is pseudo- The basis of shadow.So ferrimagnet and nonferromugnetic material can generate artifact, magnetic field intensity is bigger, ferrimagnet magnetization Rate is bigger, and quality is bigger, and artifact is more serious.Artifact not only deforms topography on image, but also can be expanded at a distance, Seriously affect picture quality.In summary：It must strictly be checked before being checked before carrying out MR and checking.To prevent metal object from depositing In the influence to inspection, various metal detectors can only be higher to coin and this kind of magnetic intensity of metal on-hook currently on the market Material is detected, the pendant weaker to some metal magnetics, underwear slide fastener and the magnetic implanted surgical material of use But it is difficult to detect, to affect the effect and working efficiency of MR diagnosis.It is simple checked by staff inevitably have an omission can Can, at the same when human body carry metal material (coin or key etc) by the strong magnetic field of MR equipment be drawn into it is scanning bed in Coin is taken to different positions by face by the movement of bed, and the artifact of generation not only directly affects the diagnosis of MR, but also in many In the case of directly result in MR equipment damage cause scanning can not continue.According to Pudong New District one, diformazan hospital not exclusively unites It is more than 120 that meter 2017 brings (wherein some is the family members for accompanying patient's inspection) into influence the case of diagnosis because of metal material Example, causes machine halt trouble up to 30.One senior MR Maintenance Engineer teaches that because metal is drawn into MR magnets Nei Laiwei The case where repairing accounts for percent the 40 or so of repair total amount.The various forms for the unconscious carrying that human body carries is removed before MR is scanned Metal material have become check preparation a very important job.

There are missing inspection flase drop wrong report etc. is a series of in the utility model serious analysis market metal detection various products Practical problem examines changing room and devises detection device pre-.It is integrated using high performance inductance sensor and microcontroller and periphery The metal detecting apparatus of the optimum organization of circuit automatically carries out top-down scanning to human body, to there are human body surfaces It is accurately detected with internal metal group material, compared with conventional detectors：Detection area working face has carried out special designing, Detection area is big, sweep speed is fast, high sensitivity." N " cluster film coil metope is covered by active picture built in frame-type metope Lid, the metal object for all kinds being hidden in human body, including jewellery can be detected by standing to turn around in specified position, A variety of materials for influencing normal MR scannings such as the tinsel on brassiere underwear.It is shown with intuitive way by large screen display Go out the metal decoration at each position of human body and internal metal material.And prompt patient's progress that can handle by voice system It extracts.The novel high 180cm of detecting devices, wide 80cm.Have the scanned metal ornament positions of materials detected to show, be aided with A variety of intelligent functions such as the alarm of LED light optical flare, voice warm tip.It is effective to prevent from examining in MR after metal material carrying Adverse consequences caused by looking into.

Utility model content

In view of the above-mentioned problems, metal object can be quickly detected the main purpose of the utility model is to provide a kind of In the presence of and accurately provide specific location information, and human body metal material before what will not be damaged to human body check for MR Detection device.

The utility model is to solve above-mentioned technical problem by following technical proposals：Human body before one kind is checked for MR The detection device of metal material, it is described to check that the detection device of preceding human body metal material includes for MR：Control core microcontroller, Metal object detector, stepper motor, photoelectric sensor, D/A converter, signal amplifier, audible-visual annunciator, large-size screen monitors are shown Device；Stepper motor controls the movement of metal object detector, the metal object detector, photoelectric sensor, D/A conversions Device, signal amplifier, audible-visual annunciator, large-screen display are both connected on core microcontroller, audible-visual annunciator, large-screen display It is both connected on signal amplifier, entire detection device is powered using power supply module.

In specific embodiment of the utility model, the hand-held POS of patient of preparation MR inspections, which enters, is equipped with gate The inspection chamber of device controls the movement of metal object detector using stepper motor, and metal object detector is between the regular hour Whether there is the position on the patient body of metal object every interior Scanning Detction, in the presence of detecting metal object, will detect Signal input to photoelectric sensor, the signal of photoelectric sensor passes sequentially through D/A converter, after signal amplifier, passes to Audible-visual annunciator, and show on large-screen display the position of metal object.

In specific embodiment of the utility model, the control core microcontroller is selected as AT90S8515 microcontrollers.

In specific embodiment of the utility model, the metal object detector is LDC1000 inductance/number conversion Device.

In specific embodiment of the utility model, the D/A converter is MAX536D/A conversion chips.

The positive effect of the utility model is：It is provided by the utility model to check preceding human body metal material for MR Detection device mainly have following advantage：1, the presence of metal object can be quickly detected and accurately provide specific position Confidence cease, 2, the utility model metal object detector utilize electromagnetic induction basic principle, using have alternating current by line Circle, generates vertiginous magnetic field.This magnetic field energy can induct eddy current inside metal object.There is eddy current and without eddy current Different signal strengths is will produce, shaping is amplified by acquisition, shaping is further amplified in analog-to-digital conversion and driving circuit, by showing Screen shows position existing for reducing metal.It is possible thereby to fundamentally avoid using x-ray detection mode unnecessary caused by human body Injury.

Description of the drawings

Fig. 1 is the overall structure diagram of the utility model.

Specific implementation mode

The utility model preferred embodiment is provided below in conjunction with the accompanying drawings, the technical solution of the utility model is described in detail.

Fig. 1 is the overall structure diagram in the utility model, as shown in Figure 1, being used for described in provided by the utility model The detection device of human body metal material includes before MR is checked：Control core microcontroller, metal object detector, stepper motor, light Electric transducer, D/A converter, signal amplifier, audible-visual annunciator, large-screen display；Stepper motor controls metal object detection The movement of device, the metal object detector, photoelectric sensor, D/A converter, signal amplifier, audible-visual annunciator, large-size screen monitors Display is both connected on core microcontroller, and audible-visual annunciator, large-screen display are both connected on signal amplifier, entire to detect Device is powered using power supply module.

Prepare the patient that MR is checked and hold the POS into the inspection chamber for being equipped with gating device, gold is controlled using stepper motor Belong to the movement of object detector, whether Scanning Detction has the trouble of metal object to metal object detector at a certain time interval The signal detected is inputed to photoelectric sensor, photoelectric sensing by the position on person's body in the presence of detecting metal object The signal of device passes sequentially through D/A converter, after signal amplifier, passes to audible-visual annunciator, and shown on large-screen display The position of metal object.

Control core microcontroller in the utility model is selected as AT90S8515 microcontrollers.

Metal object detector is LDC1000 inductance/digital quantizer in the utility model.

Metal object detector utilizes the basic principle of electromagnetic induction, using have alternating current by coil, generate rapid Changing magnetic field.This magnetic field energy can induct eddy current inside metal object.There is eddy current and will produce difference without eddy current Signal strength, shaping is amplified by acquisition, shaping is further amplified in analog-to-digital conversion and driving circuit, is shown and is restored by display screen Position existing for metal.It is possible thereby to fundamentally avoid using the unnecessary injury caused by human body of x-ray detection mode.

D/A converter in the utility model is MAX536D/A conversion chips.

With AT90S8515, core, AT90S8515 are based on AVR enhancings performance, risc architecture to the utility model in order to control Low-power consumption, CMOS technology, eight-bit microcontroller (Enhanced RISC Microcontrollers).AVR cores are 32 general Register and abundant instruction set.32 registers are all connect with arithmetic and logical unit so that can be within a clock cycle It executes an instruction and two independent registers is accessed.AT90S8515 has the Downloadable flash storage of 8K bytes, 512 words The RAM of section, 32 general purpose Is/O lines, 512 byte EEPROM (service life is 100,000 times), the flexibility timing with comparison pattern Device, programmable serial UART, inside and out interrupt, programmable watchdog (WDT) timer with internal crystal oscillator；One is Download program and the SPI serial ports designed and 2 battery saving modes that can be selected by software.It can also similar 51 series one Sample, when using external SRAM, the former exports as the address/data mouth being multiplexed, the latter as address, and DH also has other many Function.In short, using AT90S8515 as embedded efficient microcontroller, without additional program storage, data storage, PWM controls special chip, and the greatly simplified hardware of system improves reliability and the safety of system.It is set with AT90S8515 The metal object probe positioners group (hereinafter referred to as detector group) of 80CmX200Cm of the meter one using array scan control.

The utility model uses LDC1000 inductance sensors as the critical piece of detection metal, and the probe of detector uses TI companies LDC1000 inductance/digital quantizer is as metal object detector.Its testing principle is former using electromagnetic induction Reason.Add an alternating current in coil, will produce alternating magnetic field around coil, at this moment if there is metal object enters this magnetic Field then can generate vortex in metal object surface.It is like with the presence of another secondary coil.The coil of LDC1000 in this way It is formed a transformer as primary coil.Since the mutual inductance of transformer acts on, in primary coil, this side can be examined Measure the parameter of secondary coil.You can be allowed easily to connect MCU by SPI interface, it can by simple peripheral coil To realize contactless inductance detection function.External metallization object and spatial position coil connected LDC1000 can be tested Relationship.Sensitivity is the most important parameters for the detectivity for weighing metal detector, and the preferable metal detector of performance ratio can be with 0.13 gram of gold is detected, non-ferrous metal is more far short of what is expected than the detection difficulty of non-non-ferrous metal, the reason is that the magnetic of non-ferrous metal Field sensing capability is very poor.The characteristics of metal detector：Advanced DSP processing chips, hypersensitivity；Intelligent liquid-crystal shows work( Can, intelligent operating system is with better function；Stronger stability, superpower anti-interference ability and adaptability；Meet HACCP System, QS systems and ISO system Specifications；Simple two-way signal detection circuit folding, it is accurate to detect iron and non-ferric gold Belong to impurity；Simple two-way signal display function；Different inductions can be shown according to metal size；It is adapted to moist, high temperature and low Warm working environment；Using stepless time adjustment motor, conveying tape speed is arbitrarily adjusted；Easy detachable rack, easy to clean, transmission Fast.

It is a completely new application that LDC1000, which is selected in metal detection, and inductance type transducer has simple in structure, measurement The series of advantages such as the high zero point stability of precision and output power are larger, major defect are sensitivity, the linearity and measurement range Mutually restrict.But the response of sensor own frequency is low, and discomfort carries out quickly dynamic and measures.But this is not inductance sensor Most fatal disadvantage, but conversion circuit is had to pass through, electricity could be exported, therefore for majority design application, it is complicated Conversion circuit be only and hinder the widely available stumbling-block of inductance sensor.TI has been selected to push away in the metal detector that we design This inductance digital quantizer gone out is then not necessarily to complicated conversion circuit, directly exports detectable digital signal by LDC1000. Higher resolution ratio：It can realize that submicron order is differentiated in the Application in Sensing of position by 16 resonant resistances and 24 inductance values There is higher reliability can provide influence caused by non-contact sensing technology avoids contact with, can extend service life of equipment for rate. LDC1000 has very high flexibility simultaneously：Sensor is allowed to be placed far from electronic product, in the position that PCB can not be placed. The characteristics of LDC1000 can not be compared there are one other equipment, has very low system cost：Using inexpensive sensor and conduction Target without magnet and has extremely low system power dissipation, and power consumption is not less than 8.5mW, under standby mode for power consumption when standard works Sufficient 1.25mW.Therefore inductance digital quantizer is used, is a kind of new way to present metallic test.It is designed as matrix form Acquire wall, it is ensured that capture small metal material.Simultaneously in order to make inductance digital quantizer be capable of providing better performance, There is higher reliability to the WeChat ID that some are detected.The sensor signal to access ADC conversions is needed to carry out conditioning amplification It is filtered, the amplification to WeChat ID is designed using high cmrr, high-precision instrument amplifier INA326.INA326 is One kind of TI companies production is used for precision instrument amplifier.It has unique topological structure, it can be achieved that positive and negative power limit of supply input/ Output, is highly suitable for single supply, low-power consumption and the application scenario of accurate measurement.It acts on the interference on the one hand reducing noise, On the other hand the detectability to weak signal is improved.Improve the measurement accuracy and transfer efficiency of analog-digital converter.

It is the U.S. to carry out digital-to-analogue conversion MAX536D/A conversion chips using chip inlet MAX536 in the utility model The product that MAXIN companies release.Its 4 tunnel of Embedded independently can synchronous control 12 high-precision double buffering digital analog converters, With 3 lines and 4 line serial line interfaces, is saved and encapsulated using 16 feet, make its taken up space smaller.OUTA, OUTB, OUTC and OUTD are Analog signal output pin.REFAB and REFCD is respectively the reference voltage input terminal of AB and CD, and LDAC is load DAC input letters Number, low level will be transmitted to input register content in corresponding DAC registers.SDI is serial data input, and SDO is string Row data output end.CS is chip select input signal, and the maximum clock of the serial line interface of sequential MAX536 is 10MHz.Therefore CS bends l After the low level of foot must keep 20ns, it could start to receive data.LDAC feet are controlled by the I/O mouths of AT90S8515.SDI draws The serial input data of foot is sent into shift register by turn by the rising edge of serial clock SCK, is converted into parallel data.Input After data fully enter shift register, set CS be high level, using CS rising edge by shift register output and line number According in dress people's input register.Then, when LDAC bends the low level of I feet, directly D/A is sent to turn the number two of input register Parallel operation is converted.

In the present invention, metal detector needs to realize the automatic detecting function within the scope of different height, program choosing It selects and vertical movement is carried out by stepper motor in Y-axis, this requirement is detected to reach whole body.Stepping is selected in Y-axis Motor is vertically moved, and the two is combined the Surface scan that can be carried out in vertical range.Operation control for stepper motor System, the integrated stepping motor controller that the professional factory that the utility model selected forms a complete production network, model-DKC-230A lead to The P0 mouths for crossing AT90S8515 microcontrollers and P3 mouthfuls are connected with stepper motor drive module, high close to switch output by positioning Low level control stepper motor movement direction, AT90S8515P0-2 mouthful output PWM waves control stepper motors movement speed and Distance, final stepper motor drive module export the operating that corresponding voltage drives stepper motor by A, B two-phase.While in order to Unexpected caused operating can be prevented abnormal, the control displacement distance for needing detecting system to be set to stepper motor, system passes through Infrared sensor module is detected, and double control is realized by DKC-230A.And language while being shone by P0-1 mouthfuls of driving LED Sound alarm system sends out prompt tone.Hardware design the utility model of metal detection positioning system is with LDC1000 inductance sensors And system needs Driving Stepping Motor, then requires power supply reliable and stable, is supplied so directly selecting numerical control source of stable pressure Electricity.Reduce the voltage to+12V, 5V and 3.3V subsequently into reduction voltage circuit to the DC voltage of+24V, to microcontroller with And other module for power supply.Selection the utility model selection OMROM reflective infrared photoelectrics switch of position sensor, distance of reaction For 1~50cm (adjustable), induction mode is diffusing reflection (nontransparent object), and operating voltage is DC4.5~5.5V, and operating current is 50mA, the way of output are that NPN is normally opened, response time 2ms.It, in this way can be random for detecting the length of linear motor stretching The position range of linear motor movement is set, to achieve the purpose that quickly to position.By comparing the performance of various motors, selection 42 stepper motors, stepping accuracy is up to 5%.Direct current generator shaft a diameter of 5mm, motor diameter 42mm, motor length are 67mm, rotating speed may be up to 4000 turns.System needs preferable human-computer interaction function, therefore big using 55 cun in peripheral circuit Screen liquid crystal display screen is connected with the universaling I/O port of AT90S8515 microcontrollers, and large-sized liquid crystal display is fully able to meet system The requirement of system, while unobscured advantage.

Before the utility model is to preventing patient from doing MR inspections, because a variety of causes carry metal material, ornaments and pendant and Self reason is studied and has been designed, and for problem state existing for current existing equipment, people can be acquired in real time by devising Body carries metal information, and obtained information is handled by microcontroller and generates multi-signal, realizes automatic alarm, prompt and display. And expected design object has been finally reached it.The realization of the utility model can reduce the equipment thing because accidentally entering interior initiation with metal Therefore scan artifact caused by reducing human factor.Improve the working efficiency of diagnostician.Safeguard the normal operation of MR equipment, this Utility model can not only be conveniently used for the preliminary examination in Medical Devices, and being upgraded modification to its module can be used for subway, machine The self-service safety check of field and high ferro entrance, improves working efficiency, and group platoon leader is arranged in solution true these industry safety checks at present The problem of team, has good development prospect.

The advantages of basic principles and main features and the utility model of the utility model have been shown and described above.One's own profession The technical staff of industry is it should be appreciated that the present utility model is not limited to the above embodiments, described in above embodiments and description Only illustrate the principles of the present invention, on the premise of not departing from the spirit and scope of the utility model, the utility model is also It will have various changes and improvements, these various changes and improvements fall within the scope of the claimed invention, the utility model Claimed range is defined by the appending claims and its equivalent thereof.

Claims (5)

1. a kind of detection device checking preceding human body metal material for MR, it is characterised in that：It is described to check preceding human body for MR The detection device of metal material includes：Control core microcontroller, metal object detector, stepper motor, photoelectric sensor, D/A Converter, signal amplifier, audible-visual annunciator, large-screen display；Stepper motor controls the movement of metal object detector, described Metal object detector, photoelectric sensor, D/A converter, signal amplifier, audible-visual annunciator, large-screen display are all connected with On core microcontroller, audible-visual annunciator, large-screen display are both connected on signal amplifier, and entire detection device uses power supply Assembly power supply.

2. the detection device according to claim 1 for checking preceding human body metal material for MR, it is characterised in that：Prepare MR The patient of inspection holds the POS and enters the inspection chamber for being equipped with gating device, and metal object detector is controlled using stepper motor Mobile, whether Scanning Detction has the portion on the patient body of metal object to metal object detector at a certain time interval Position, in the presence of detecting metal object, inputs to photoelectric sensor, the signal of photoelectric sensor is successively by the signal detected By D/A converter, after signal amplifier, audible-visual annunciator is passed to, and the position of metal object is shown on large-screen display It sets.

3. the detection device according to claim 1 for checking preceding human body metal material for MR, it is characterised in that：The control Core microcontroller processed is selected as AT90S8515 microcontrollers.

4. the detection device according to claim 1 for checking preceding human body metal material for MR, it is characterised in that：The gold Category object detector is LDC1000 inductance/digital quantizer.

5. the detection device according to claim 1 for checking preceding human body metal material for MR, it is characterised in that：The D/ A converters are MAX536D/A conversion chips.