CN100376221C - Device for measuring length of teeth root canal - Google Patents
Device for measuring length of teeth root canal Download PDFInfo
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- CN100376221C CN100376221C CNB2005100918885A CN200510091888A CN100376221C CN 100376221 C CN100376221 C CN 100376221C CN B2005100918885 A CNB2005100918885 A CN B2005100918885A CN 200510091888 A CN200510091888 A CN 200510091888A CN 100376221 C CN100376221 C CN 100376221C
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Abstract
The present invention relates to a length-measuring instrument of tooth root canals, which belongs to a length-measuring device, particularly to a length-measuring device of human tooth root canals. The present invention provides a length-measuring instrument of tooth root canals, which has the advantages of good operability, power consumption saving and low cost. The present invention comprises a measuring circuit, a digital comparator circuit, a logic control circuit, an acoustic-opticalarm circuit and a display circuit, wherein a detecting head of the measuring circuit is connected with a tooth root tip, and the input terminal of the digital comparator circuit is connected with the measuring circuit; the input terminal of the logic control circuit is connected with the digital ratio output of the digital comparator circuit, the input terminal of the acoustic-optic alarm circuit is connected with the logic control circuit, and the input terminal of the display circuit is connected with the digital comparator output terminal of the digital comparator circuit. A general analog-digital conversion chip is adopted to realize digital proportional operation; compared with a micro-processing chip, the analog-digital conversion chip can simplify circuits and reduce cost. In theory, operational precision can reach 1/256 of input direct current voltage, and measuring targeting ranges are controlled in about 16 states. With the advantage of good operability, the present invention not only considers both product performance and battery consumption but also can reduce cost. A buffer insulating stage is added between a detecting terminal and a sampling input terminal so that the present invention has good linearity of response change and high sensibility.
Description
Technical field
The present invention relates to a kind of length-measuring appliance, especially relate to a kind of measuring device of human teeth's sono-explorer.
Background technology
The accurate measurement of human teeth's sono-explorer is the step that oral medicine must be finished in carrying out the tooth root canal, is related to the effect and the success or failure of treatment.Conventional means in the past is feel measurement method and x-ray imaging method, and the former accuracy the not good enough latter will repeatedly make film in therapeutic process, has both increased patient's expense, has increased again to accept radiating danger.
In recent years, along with the histological development of human oral cavity, a kind of novel root canal length electric measuring instrument simple, easy-to-use, that accuracy is high has grown up.Since 1979, experienced the three generations.The first generation (impedance method) is that the size with tooth tip of a root position resistance is a design principle, and instrument is simple, inexpensive, but accuracy does not reach clinical requirement, the oral cavity physicochemical environment is required high, uses inconvenience, and is superseded.The second filial generation (voltage gradient method, electric current density method) is that the resistance change rate with tip of a root position is a design principle, realizes difficulty, the circuit complexity, and instrument cost height, accuracy is still undesirable, and is only short-lived.The third generation (rule of three, frequency response relative value method) is to be design principle with the anti-response pattern to two kinds of different frequency alternating currents of root tip steric hindrance, its typical case represent instrument for day Benson field making the ROOT-ZX root canal length meter.This instrument is easy to use, the accuracy of measurement height, and clinical practice is reliable, repeatedly is seen in domestic relevant article report.This instrument application advanced microprocessor processes technology, and special-purpose Color Liquid Crystal Display chip, but cost is high, domestic price is about 9000 yuans every, has limited it and has applied.
Summary of the invention
The objective of the invention is to defectives such as the operability that the measure the root canal length device at the design of existing employing rule of three, frequency response relative value method exists is relatively poor, power consumption big, involve great expense, a kind of preferable operability, power consumptive province, device for measuring length of teeth root canal that cost is low are provided.
The present invention is provided with
Measuring circuit, be used to survey of the variation of tooth root tip position resistance value to two kinds of different frequency alternating current responses, and the two paths of signals that is varied to direct ratio of the corresponding two kinds of different frequency alternating currents response of output and tooth tip of a root position, the external tested tooth tip of a root of the detecting head of measuring circuit position;
Digital comparator is used for the two-way response signal of measuring circuit output is compared and exports the digital quantity of its ratio, the two-way response signal outfan of the input termination measuring circuit of digital comparator;
Logic control circuit is used for according to the parameter determination number word arithmetic result who sets, and the output control signal, the ratio digital quantity outfan of the input termination digital comparator of logic control circuit;
Sound light alarming circuit is used to point out measuring instrument residing different set state, the control signal output ends of the input termination logic control circuit of sound light alarming circuit;
Display circuit is used for showing the measuring process digital comparison results, the digital comparison results outfan of the input termination digital comparator of display circuit.
Said measuring circuit is provided with the agitator that produces two different frequency AC signals, characteristic is the hybrid circuit of constant-current source character, detecting head, the buffering buffer circuit of two-way response signal voltage, two-way frequency frequency selection circuit, two-way detecting circuit and two-way DC voltage amplifying circuit, the output of two agitators connects detecting head respectively behind hybrid circuit, the two response signal outfans that detecting head detects connect the input of two-way buffering buffer circuit respectively, the outfan of two-way buffering buffer circuit connects the input of two-way frequency selection circuit respectively, the outfan of two-way frequency selection circuit connects the input of two-way detecting circuit respectively, and the outfan of two-way detecting circuit connects the input of two-way amplifying circuit respectively.
The function of measuring circuit is to search the variation of two kinds of different frequency sinusoidal signals in the measuring process, and exports and be varied to the direct-flow signal voltage of direct ratio.Digital comparator obtains two-way DC voltage (analog quantity) digital quantity of their ratio after digital operation.Logic control circuit is according to different setting (early warning, put in place, excessive) determination number word arithmetic result, and the output control signal is used to control sound and light alarm.Sound light alarming circuit rings and the residing different set state of different colours luminous tube prompting operation person instrument with different news.Display circuit shows the variation of digital comparison results in the measuring process intuitively.
Digital comparator adopts general modulus conversion chip to realize the numerical scale computing.With the two-way analogue signal of measuring circuit output, the one tunnel as converted input signal voltage, connects and use the modulus conversion chip input; Another road is connected with modulus conversion chip reference voltage end as reference voltage; Transformation result directly obtains the n bit digital quantity of two-way aanalogvoltage ratio, its output termination logic control circuit input and display circuit input.
Logic control circuit adopts general logic control hardware, comprises that two-way decoder, two-way trigger and corresponding digital logic gates realize jointly; N bit digital comparison circuit output signal divides two-way to connect the input of two-way decoder respectively after the corresponding digital logic gates, two-way decoder output (m road) respectively is set at two-way output through adjusting, connect the input of two-way trigger respectively, the outfan of two-way trigger then joins with the input of sound light alarming circuit respectively.
The present invention designs according to the response pattern of tooth root tip position resistance value to two kinds of different frequency alternating currents, because to different physicochemical environments in Different Individual and the oral cavity, though its impedance variation rule has nothing in common with each other, but when arriving tip of a root position, the ratio of two kinds of responses is tending towards certain value, therefore by design of the present invention, its measurement result has preferable accuracy.
Advantage of the present invention is: 1, owing to adopt the general modulus conversion chip of ADC0804 to realize the numerical scale computing, adopt the technology of little process chip to simplify circuit widely compared with imported product, therefore reduced cost, the market price estimates to be reduced to 1/5～1/8 of imported product; Secondly, operational precision can reach 1/256 of input direct voltage in theory, and (256 kinds of output states are arranged), the present invention's measurement scope of putting in place is controlled at about 16 kinds of states, compared with about 48 kinds of states of import model machine stronger operability is arranged.2, the selected general low-power consumption IC components and parts of complete machine, and adopt the super low-power consumption bistable relay, both taken into account properties of product and battery consumption, reduced product cost again.Only 20 milliamperes of complete machine power consumptions are half of import model machine.3, add the buffering isolation level between end of probe and the sampling input, make result of detection not be subjected to the influence of instrument sending-end impedance, the contrast test result, better than the response change linearity of import machine, sensitivity is higher.4, increased the light emitting diode warning circuit, like this, the present invention has indication electric meter, sound and luminous three kinds of type of alarms simultaneously, more convenient practical application, and clinical use proof operability has bigger improvement compared with the import model machine.5, Chong Xinsheji self-calibration circuit and start zeroing circuit have guaranteed high accuracy, the high reliability of consistency of product and measurement.
Description of drawings
Fig. 1 is the structure composition frame chart of the embodiment of the invention.
Fig. 2 is the structure composition frame chart of embodiment of the invention measuring circuit part.
Fig. 3 is the structure composition frame chart of embodiment of the invention logic control circuit part.
Fig. 4 is the circuit theory diagrams of embodiment of the invention measuring circuit part.
Fig. 5 is the circuit theory diagrams of embodiment of the invention digital comparator, logic control circuit, display circuit part and sound light alarming circuit part.
The specific embodiment
Following examples will the present invention is further illustrated in conjunction with the accompanying drawings.
As shown in Figure 1, 2, the present invention is provided with measuring circuit 1, digital comparator 2, logic control circuit 3, sound light alarming circuit 4 and display circuit 5.Measuring circuit 1 is used to survey the responsive impedance value that tooth tip of a root position changes two kinds of different frequency alternating currents, and output and tooth tip of a root position are varied to the two-way response signal of direct ratio, the detecting head 10 external tested tooth tip of a root positions of measuring circuit 1 to two kinds of different frequency alternating currents; Digital comparator 2 is used for the two-way response signal of measuring circuit output is compared and exports the digital quantity of its ratio, the two-way response signal outfan of the input termination measuring circuit 1 of digital comparator 2; Logic control circuit 3 is used for according to the parameter determination number word arithmetic result who sets, and the output control signal, the ratio digital quantity outfan of the input termination digital comparator 2 of logic control circuit 3; Sound light alarming circuit 4 is used to point out measuring instrument residing different set state, the control signal output ends of the input termination logic control circuit 3 of sound light alarming circuit 4; Display circuit 5 is used for showing the measuring process digital comparison results, the digital comparison results outfan of the input termination digital comparator 2 of display circuit 5.
Said measuring circuit 1 is provided with the agitator 11 and 12 that produces two different frequency AC signals, characteristic is the hybrid circuit 13 of constant-current source character, detecting head 10, the buffering buffer circuit 14 and 15 of two-way response signal voltage, two-way frequency frequency selection circuit 16 and 17, two-way detecting circuit 18 and 19 and two-way DC voltage amplifying circuit 20 and 21, two agitators 11 and 12 output connect detecting head 10 respectively behind hybrid circuit 13, the two response signal outfans that detecting head 10 detects connect the input of two-way buffering buffer circuit 14 and 15 respectively, two-way buffering buffer circuit 14 and 15 outfan connect the input of two-way frequency selection circuit 16 and 17 respectively, two-way frequency selection circuit 16 and 17 outfan connect the input of two-way detecting circuit 18 and 19 respectively, and two-way detecting circuit 18 and 19 outfan connect the input of two-way amplifying circuit 20 and 21 respectively.
As an example, agitator 11 and agitator 12 produce the sine wave that frequency is 400Hz and 8000Hz respectively, through characteristic are to obtain modulating wave and deliver to detecting head 10 behind the hybrid circuit of constant-current source character; The response signal voltage that detecting head 10 inspection is picked up is delivered to 400Hz and 8000Hz signal voltage after two-way frequency separation circuit is isolated response through two-way buffering isolation level, deliver to peak-detector circuit separately then, obtain being proportional to the DC voltage of response back signal voltage peak value; After being amplified to suitable level, amplifier 20 and amplifier 21 send to the digital comparator 2 of back again.
Digital comparator adopts general modulus conversion chip to realize the numerical scale computing, general modulus conversion chip input termination measuring circuit conversion input analog signal voltage outfan, general modulus conversion chip reference voltage termination measuring circuit reference voltage analog signal output; Transformation result directly obtains the n bit digital quantity of two-way aanalogvoltage ratio, its output termination logic control circuit input and display circuit input.
As shown in Figure 3, said logic control circuit adopts general logic control hardware, comprises two-way decoder 22,23, and two-way trigger 24,25 and corresponding digital logic gates realize jointly; N bit digital comparison circuit output signal divides two-way to connect the input of two-way decoder respectively after the corresponding digital logic gates, two-way decoder output (m road) respectively is set at two-way output through adjusting, connect the input of two-way trigger respectively, the outfan of two-way trigger then joins with the input of sound light alarming circuit respectively.
Referring to Fig. 4,5, integrated operational amplifier AR101-1, AR102-2 constitutes Wen's bridge oscillating circuit of auto_steady amplitude; Integrated operational amplifier AR102-1 is the buffering isolation level; Integrated operational amplifier AR103-1, AR103-2 constitutes frequency selection circuit, and mid frequency is 400Hz, and Q-value is 2, and the attenuation rate of 40db/ ten frequencys multiplication is arranged; Integrated operational amplifier AR103-3 constitutes peak-detector circuit, and output dc voltage is transported to digital comparator after integrated operational amplifier AR103-4 amplifies.The principle of another road 8000Hz is similar.
For reducing cost and cost, it is the scheme of core that the present invention abandons with the microprocessor, adopt special analog digital operation method and logical controlling hardware to realize, wherein adopt the ADC0804 of National Semiconductor modulus conversion chip, with the two-way analogue signal, the one tunnel as converted input signal voltage, and another road is as reference voltage, transformation result directly obtains the digital quantity of two-way aanalogvoltage ratio, realizes the numerical scale calculation function.
IC 201 is finished digital comparing function, exports 8 bit comparisons digital quantity as a result, and IC 202 is realized display circuit function (IC 203 provides negative supply for its work), the direct drive current table of output current M201; Decoder IC203, IC204, trigger IC205 and digital logic gate circuit U 201, U203 realize the logic control circuit function jointly; The audible alarm circuit that output signal is controlled warning light emitting diode D203, D204 respectively and is made of integrated gate circuit U202.Audion Q201, low-power relay SW201, three-terminal voltage-stabilizing power supply IC207 etc. constitute auxiliary circuits such as timing shutdown and power supply indication.
Below provide components and parts among Fig. 3 with reference to model and parameter.
Integrated operational amplifier AR101, AR102, AR104:TL062 type, AR103, AR105:TL064 type.
Field effect transistor Q101, the Q102:2SK30A type.
Diode D101, D102, D103, D104, D105, D106:1N4148 (1S1588) type.
Resistance R 101, R102, R112, R114, R115, R116, R117, R120, R121, R122, R123:180K; R103, R119, R127, R130, R145, R151, R153:10K; R104, R131:22K; R105, R132:1M; R106, R108, R126, R133, R135, R152:100K; R109, R110, R111, R136, R137, R138H:47K; R113:7.8K; R118, R124, R144, R150, R154:6.8K; R128, R129, R140, R141, R142, R143, R146, R147, R148, R149:9.1K; R139:220K.
Miniature multiturn potentiometer R107, R134:50K; R125, R155:20K.
Capacitor C 101, C102, C104, C105, C106, C107, C110, C111, C113, C114, C115, C116:2200P; Electrochemical capacitor C103, C112:10 μ; C108, C109, C117, C118:1 μ.
Below provide components and parts among Fig. 4 with reference to model and parameter.
IC 201:ADC0804 type; The IC202:DAC0832 type; The IC203:CW7660 type; IC204, the IC205:CD4028 type; The IC206:CD4027 type.Three-terminal voltage-stabilizing power supply IC207:LM2931 type.
Logic gates U203:CD4023 type; The U202:CD74HC00 type; The U201:CD74HC04 type.
Integrated operational amplifier AR201:LM358 type.
Audion Q201, the Q202:9011 type.
Zener diode D201, the D202:LM336-2.5 type.
Light emitting diode D204, D203, D205.
Resistance R 201, R207, R211:10K; R202, R203, R206, R214:2.2K; R204, R212:4.7K; R205, R213:3.3K; R208:10M; R209, R210:1K.
Potentiometer R215:20K.
Capacitor C 201:100P; C202, C203:10 μ; C204:4.7 μ, C205:47 μ; C206:22 μ; C207:47 μ; C208:0.1 μ; C209:100 μ.
Relay SW201: low-power consumption type.
Claims (2)
1. device for measuring length of teeth root canal is characterized in that being provided with:
Measuring circuit, be used to survey of the variation of tooth root tip position resistance value to two kinds of different frequency alternating current responses, and the two paths of signals that is varied to direct ratio of the corresponding two kinds of different frequency alternating currents response of output and tooth tip of a root position, the external tested tooth tip of a root of the detecting head of measuring circuit position;
Digital comparator, be used for the two-way response signal of measuring circuit output is compared and exports the digital quantity of its ratio, the two-way response signal outfan of the input termination measuring circuit of digital comparator, digital comparator adopts general modulus conversion chip to realize the numerical scale computing, general modulus conversion chip input termination measuring circuit conversion input analog signal voltage outfan, general modulus conversion chip reference voltage termination measuring circuit reference voltage analog signal output; Transformation result directly obtains the n bit digital quantity of two-way aanalogvoltage ratio, its output termination logic control circuit input and display circuit input;
Logic control circuit, be used for according to the parameter determination number word arithmetic result who sets, and output control signal, the ratio digital quantity outfan of the input termination digital comparator of logic control circuit, logic control circuit adopts general logic control hardware, comprises two-way decoder, two-way trigger and Digital Logic gate circuit; The input termination n bit digital comparison circuit output signal of two-way decoder divides two-way through the corresponding digital logic gates, the two-way decoder output respectively is set at two-way output through adjusting, connect the input of two-way trigger respectively, the outfan of two-way trigger connects the input of sound light alarming circuit respectively;
Sound light alarming circuit is used to point out measuring instrument residing different set state, the control signal output ends of the input termination logic control circuit of sound light alarming circuit;
Display circuit is used for showing the measuring process digital comparison results, the digital comparison results outfan of the input termination digital comparator of display circuit.
2. device for measuring length of teeth root canal as claimed in claim 1, it is characterized in that said measuring circuit is provided with the agitator that produces two different frequency AC signals, characteristic is the hybrid circuit of constant-current source character, detecting head, the buffering buffer circuit of two-way response signal voltage, two-way frequency frequency selection circuit, two-way detecting circuit and two-way DC voltage amplifying circuit, the output of two agitators connects detecting head respectively behind hybrid circuit, the two response signal outfans that detecting head detects connect the input of two-way buffering buffer circuit respectively, the outfan of two-way buffering buffer circuit connects the input of two-way frequency selection circuit respectively, the outfan of two-way frequency selection circuit connects the input of two-way detecting circuit respectively, and the outfan of two-way detecting circuit connects the input of two-way amplifying circuit respectively.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB2005100918885A CN100376221C (en) | 2005-08-15 | 2005-08-15 | Device for measuring length of teeth root canal |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB2005100918885A CN100376221C (en) | 2005-08-15 | 2005-08-15 | Device for measuring length of teeth root canal |
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| Publication Number | Publication Date |
|---|---|
| CN1729948A CN1729948A (en) | 2006-02-08 |
| CN100376221C true CN100376221C (en) | 2008-03-26 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNB2005100918885A Expired - Fee Related CN100376221C (en) | 2005-08-15 | 2005-08-15 | Device for measuring length of teeth root canal |
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| Country | Link |
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| CN (1) | CN100376221C (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113057745A (en) * | 2021-03-24 | 2021-07-02 | 桂林市啄木鸟医疗器械有限公司 | Root canal treatment system based on voice control and control method |
Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN86108611A (en) * | 1986-12-19 | 1987-09-02 | 中国人民解放军第四军医大学口腔医院 | Audio detector for dental canal length |
| CN2050317U (en) * | 1989-05-16 | 1990-01-03 | 张庆 | Tooth length acoustoopic detector |
| US5211556A (en) * | 1991-11-27 | 1993-05-18 | Kabushiki Kaisha Morita Seisakusho | Root canal meter |
| US5295833A (en) * | 1991-09-30 | 1994-03-22 | Kabushiki Kaisha Morita Seisakusho | Dental root canal diagnostic and treating equipment |
| JPH06181939A (en) * | 1992-08-27 | 1994-07-05 | Morita Mfg Co Ltd | Ultrasonic root canal therapeutic unit with root canal length measuring function |
| JPH07163597A (en) * | 1993-12-03 | 1995-06-27 | Osada Res Inst Ltd | Root canal treating device |
| WO2001047414A1 (en) * | 1999-12-27 | 2001-07-05 | Forum Engineering Technologies (96) Ltd. | Device for detection of a tooth root apex |
| EP1384449A1 (en) * | 2002-07-26 | 2004-01-28 | Aseptico International | Systems and methods for locating a tooth's apical foramen |
-
2005
- 2005-08-15 CN CNB2005100918885A patent/CN100376221C/en not_active Expired - Fee Related
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN86108611A (en) * | 1986-12-19 | 1987-09-02 | 中国人民解放军第四军医大学口腔医院 | Audio detector for dental canal length |
| CN2050317U (en) * | 1989-05-16 | 1990-01-03 | 张庆 | Tooth length acoustoopic detector |
| US5295833A (en) * | 1991-09-30 | 1994-03-22 | Kabushiki Kaisha Morita Seisakusho | Dental root canal diagnostic and treating equipment |
| US5211556A (en) * | 1991-11-27 | 1993-05-18 | Kabushiki Kaisha Morita Seisakusho | Root canal meter |
| JPH06181939A (en) * | 1992-08-27 | 1994-07-05 | Morita Mfg Co Ltd | Ultrasonic root canal therapeutic unit with root canal length measuring function |
| JPH07163597A (en) * | 1993-12-03 | 1995-06-27 | Osada Res Inst Ltd | Root canal treating device |
| WO2001047414A1 (en) * | 1999-12-27 | 2001-07-05 | Forum Engineering Technologies (96) Ltd. | Device for detection of a tooth root apex |
| EP1384449A1 (en) * | 2002-07-26 | 2004-01-28 | Aseptico International | Systems and methods for locating a tooth's apical foramen |
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