CN1103206C - Dental syringe with circuit for detecting connecting point, charge driving device and illumination device built in - Google Patents

Abstract

The invention provides a contact detecting circuit which surely detects the open/ close of contact of a switch, etc., to provide a load drive device and also to provide a dental syringe with a built-in illuminator and can improve its durabil ity, operability, etc. A load drive device consists of a handpiece main body and a load control circuit. The main body contains an illumination power supply and a switch which includes the conduction members. The circuit contains an oscillation circuit which generates an AC signal to be applied to the member, a signal detecting circuit which rectifies and smoothes the signal received from the member when the switch is closed, a comparator which compares the output signal of the circuit with the prescribed reference value, a control circuit, and a drive circuit which supplies the power to the power supply from a power circuit based on the control signal of the circuit.

Description

The built-in dental syringe of circuit for detecting connecting point and illuminator

Technical field

The present invention relates to a kind of circuit for detecting connecting point that electric contact opens and closes that detects, and detect the load driving circuits of the switching of electric terminal and driving light source or motor and then relate to the dental syringe of the illuminator of a kind of built-in illumination therapentic part etc.

Background technology

In the past in dental treatment, in order to cut tooth, remove tartar, clean therapentic part and to reclaim cutting chip or saliva etc., use various functional units such as resembling air turbine functional unit, miniature motor functional unit, scaler, three usefulness syringes, vacuum syringe.When using these functional units to carry out dental care, operation is set on the diagnosis and treatment platform in addition throw light on illuminating lamp boil on the nape opposite the mouth intracavity and treat operation.

But if patient's posture or treatment doctor's direction of operating one changes, intraoral illumination will produce shade, makes and observes the difficulty that becomes, and whenever this situation all has to adjust the position of working lights, this just causes treating the decline of operability.

Therefore, concealable lamp and light emitting diode in the functional unit body have also been implemented in recent years exploitation, penetrate throw light on a kind of functional unit (as Japan Patent real fair 3-13301 number, real fair 3-19369 number) of treatment operation and therapentic part of light from the functional unit front end.

Fig. 9 is the block diagram that the existing operating portion electricity of expression constitutes.In operating portion body 1, in keep illumination light source 2, on the other hand, for being provided with the light switch 5 that the control lamp is used on the load control circuit 4 of driving light source 2, the electric power of being supplied with by load control circuit 4 transmits by drive wire 3.Light switch 5 by manually operated console switch such as operator's hands or foot or by be equipped on the operating portion body work asynchronously with the dental instrument and permutator of opening and closing etc. constitutes.

In syringe in the past, be used to open and close the handle of air pipe line and water lines and be provided with respectively for the light switch that opens and closes built-in light source.Therefore, the internal structure complexity of syringe is difficult to miniaturization.

In addition in order to prevent the infection etc. in the hospital, suitably implement to disinfect or hot and humid sterilization treatment etc., be very necessary to keep syringe often to clean, still, electric parts such as light switch are very low for the durability of sterilization treatment generally.And the parts such as switch that durability is strong are very expensive often and volume is big.

And then in common treatment operation, affected part must throw light on when spraying fluid such as water or air to affected part.But because handle and light switch that jet fluid is used are provided with respectively, it is pretty troublesome while operating grip and light switch, and this just causes treating miscellaneousization of operation.

Summary of the invention

The circuit for detecting connecting point that the purpose of this invention is to provide contact open and-shut modes such as a kind of sense switch definitely inerrably.

Another object of the present invention provides the open and-shut mode of contact such as a kind of sense switch positively, thereby reliably inerrably drives the load drive device of loaded work piece.

Another purpose of the present invention provides a kind of durability height to sterilization treatment etc., and component quantity is few and the light weight miniaturization, further improved the built-in dental syringe of illuminator of operability.

The invention provides a kind of circuit for detecting connecting point, it is characterized in that comprising: 2 conductive components change relative positions and isolate mutually or the contact hands section of contact; Generation is to the oscillating circuit of a side the additional AC signal of conductive component; And the output signal of the opposing party's conductive component carried out rectification, the signal deteching circuit of smothing filtering.

According to signal deteching circuit of the present invention, owing to have in two conductive components that constitute electric contact, one side is added AC signal, and the opposing party's output signal is carried out the signal deteching circuit of rectification, smothing filtering, therefore, though influence such as conductive component is worn, burn into oxidation, pollution and the D.C. resistance of contact is increased, because approaching along with 2 conductive components, AC impedance reduces, and therefore can detect the opening and closing operations of contact definitely.

Another feature of the present invention is that above-mentioned AC signal frequency is more than 1KHz.

Another feature of the present invention is that above-mentioned circuit for detecting connecting point has a slow start circuit that can relax above-mentioned comparison circuit output signal rising and descend.

In addition, another feature of the present invention is: above-mentioned circuit for detecting connecting point has the power transfer adjustor of a powering load.

Similarly, according to circuit for detecting connecting point of the present invention, owing to have in 2 conductive components that constitute electric contact, a side added AC signal, and the opposing party's output signal is carried out the signal deteching circuit of rectification, smothing filtering, therefore, even increase owing to the deterioration of contact makes its D.C. resistance, because approaching along with 2 conductive components, AC impedance reduces, therefore, can detect both contact open and-shut modes definitely.In addition, can compare according to reference signal and detect clearly having or not of contact open closed operation the output signal of signal deteching circuit and regulation.And then, learn that contact opens and closes to operate that load driving circuits is just given the power supply of light source or motor even load according to comparative result.This just can positively detect the contact open closed operation, reliably inerrably drives loaded work piece.

In addition, because the frequency of AC signal is more than 1KHz, therefore along with the opening and closing operations of contact, the variation of the AC impedance between contact is big, thereby the variation quantitative change of detection signal is big, and this just can realize more definite reliable detection.

Because load driving circuits has the rising of the output signal that can make comparison circuit and the demulcent slow start circuit that descends, this just can make the electric current that is added in the load slowly rise or descend again.Therefore, alleviated the rapid variation of burst current even load electric current, this just can prevent the baneful influence to load.

Because load driving circuits has the power transfer adjustor of powering load, therefore can realize losing few load control again.

The invention provides the built-in dental syringe of a kind of illuminator, it is characterized in that it has: the lighting mechanism that produces illumination light; The fluid that guiding is supplied with from the outside, and make near its most advanced and sophisticated fluid passage that sprays from syringe body; Valve body for inaccessible or open above-mentioned fluid passage; And isolate with above-mentioned valve body or contact, and allow the modified gear of this valve body change position; Have contactless to control the illumination controlling organization of above-mentioned lighting mechanism by above-mentioned valve body of electro-detection and above-mentioned modified gear.

One of feature of this invention is to have the handle that moves above-mentioned modified gear, and above-mentioned valve body and above-mentioned modified gear are made of conductive material, and above-mentioned handle and above-mentioned modified gear are by electric insulation fully.

According to the present invention, owing to add DC voltage or alternating voltage between valve body and modified gear, both have contactless by electro-detection.Control lighting mechanism, therefore, there is no need the other light switch that is set to control light source separately, this just can reduce used unit and make simple structure.And then, owing to there is not the low electronic unit of useful life longevity, therefore, can carry out that globality is disinfected and sterilization treatment to syringe.Again owing to can detect air at an easy rate or whether water or other fluid sprays, therefore, can with the fluid ejection operation control of synchronously throwing light on, this has just improved the operability of the work for the treatment of.

And then because the handle that modified gear is moved is arranged, this has just reduced the desired power of operating valve body.Because valve body and modified gear are made of conductive material, therefore can detect both contact conditions definitely again.Because handle and modified gear are electric insulations, therefore, detect current in loop and just can not leak into handle again, this just can prevent the generation of operator's electric shock accidents definitely.

In addition, the invention provides the built-in dental syringe of a kind of illuminator, it is characterized in that it has: one produces the lighting mechanism of illumination light; The fluid that guiding is supplied with by the outside also makes near its fluid path from spraying the injection body tip; One makes the inaccessible or open valve body of above-mentioned fluid passage; Isolate with aforementioned valve body or contact, and make the modified gear of this valve body change position; Generation is added on the oscillating circuit of the AC signal on the side of aforementioned valve body or aforementioned modified gear; The signal of the opposing party of aforementioned valve body or aforementioned modified gear output is carried out the signal deteching circuit of rectification, smothing filtering; The comparison circuit that the output signal and the specified reference value of above-mentioned signal deteching circuit compared; And, drive the illumination driving circuit of above-mentioned lighting mechanism according to the output signal of aforementioned comparison circuit.

And according to syringe of the present invention, constitute electric contact by valve body and modified gear, and have on a certain side to valve body or modified gear and add AC signal, the opposing party's output signal is carried out the signal deteching circuit of rectification, smothing filtering, therefore, even owing to the deterioration of contact causes D.C. resistance to increase, approaching mutually by valve body and modified gear, its AC impedance is reduced, therefore still can detect both contact open and-shut modes definitely.Owing to output signal and specified reference value with signal deteching circuit compare, therefore can detect clearly having or not of contact open closed operation again.And then when detecting the contact open closed operation according to comparative result, illumination driving circuit just drives lighting mechanism work.Like this,, therefore the light switch that driving light source is used can be set separately in addition, the simplification that this just can make the minimizing of used unit quantity and structure is set owing to whether contact with modified gear and drive lighting mechanism by detecting valve body definitely reliably.And then, because the low electronic unit of useful life longevity not, can implement therefore that globality is disinfected or sterilization treatment to syringe.Again owing to be easy to detect having or not of fluid ejection operation such as water or air, therefore can with the fluid ejection operation control of synchronously throwing light on, this has just improved the operability of the work for the treatment of.

Followingly describe embodiments of the invention in detail with reference to accompanying drawing.

From following detailed description and appended drawing can further clear and definite above-mentioned purpose of the present invention, feature and advantage.

Description of drawings

Fig. 1 is the block diagram that the expression principle of the invention constitutes.

Fig. 2 is the variation of Fig. 1.

Fig. 3 is the block diagram of expression one embodiment of the invention.

Fig. 4 is the circuit diagram of the concrete formation of load drive device 10 in the presentation graphs 3.

Fig. 5 is the sectional view of expression as the three usefulness syringes 40 of one embodiment of the invention.

Fig. 6: Fig. 6 (a) is the end-view of jet pipe 47 shown in Figure 5;

Fig. 6 (b) is the sectional view of Fig. 5 from the B1-B1 line; Fig. 6 c) is sectional view from Fig. 5 B2-B2 line.

Fig. 7 is the figure of expression light guide 30 shapes shown in Figure 5, and wherein: Fig. 7 (a) is its plane graph, and Fig. 7 (b) is its front elevation, and Fig. 7 (c) is its ground plan.

Fig. 8 is the sectional view that the part of Fig. 5 is amplified.

Fig. 9 represents the block diagram of the electricity formation of operating portion in the past.

The specific embodiment

Now embodiments of the invention are elaborated:

Fig. 1 is the block diagram that the expression principle of the invention constitutes.On operating portion body 11, be provided with the illuminating light source 12 of lamp or light emitting diode and so on, and then be provided with switch 13 into control light source 12.By the break-make of holding wire 15 sense switches 13, in case while switch 13 closures, it is shinny by drive wire 14 light source 12 to be switched on again on the one hand for load control circuit 16.So, owing to be provided with switch 13 on the operating portion body 11, therefore improved the operability of treatment operation greatly.

Fig. 2 is the example of the distortion of Fig. 1.Operating portion body 11 and load driving circuits 16 are coupled together by three lines of 17a-17c, and wherein 17a is as drive wire, and 17c is as holding wire, and 17b is as common line.So compared to Figure 1, Fig. 2 just can reduce and uses the line number.

Fig. 3 is the block diagram of expression one embodiment of the invention.Load drive device 10 is made of operating portion body 11 and load control circuit 16.Operating portion body 11 possesses lamp or light emitting diode and so on illumination light source 12 and the conductive component 13a that realizes by the change relative position cutting off or contacting and the switch 13 of 13b formation is arranged.

Load control circuit 16 has: produce the oscillating circuit 21 that is added on the AC signal on the conductive part 13a by holding wire 15; The signal that when switch 13 cuts out conductive component 13b is come carries out the testing circuit 22 of rectification, smothing filtering; The comparison circuit 23 that the reference signal of the output signal of testing circuit 22 and regulation is compared; According to the output signal of comparison circuit 23, the circuit 24 of output control signal; Based on the control signal of control circuit 24, power circuit 26 electrical power supplied are offered the drive circuit 25 of light source 12 by drive wire 14.

The following describes the system works situation.At first, do not close a switch 13 o'clock the operator, because conductive component 13a and conductive component 13b are separated from each other, the AC signal that therefore is added on the conductive component 13a just can not pass on the conductive component 13b.So at this moment the signal level that detected of signal deteching circuit 22 almost is zero V.Comparison circuit 23 is made the judgement that signal level is lower than the stipulated standard level, for example just exports a kind of high level signal.In addition,, just sneak into extraneous noise easily, but, therefore improved the noiseproof feature of system because comparison circuit 23 is distinguished the level height if holding wire 15 is long.If the output of comparison circuit 23 is high level, then because control circuit 24 does not make drive circuit 25 work, so light source 12 does not just work.

Secondly, for obtaining illumination light, if operator's Closing Switch 13, because conductive component 13a would be near conductive component 13b and contact with it, so between obtains conduction of current.But because wearing and tearing, the burn into oxidation of conductive component 13a, 13b, influence such as get dirty, the D.C. resistance of the contact point that grows with time will increase gradually.Particularly when conductive component 13a, 13b used the metal material of Titanium or rustless steel and so on strong corrosion resistant, the oxide layer thin film on surface can make the direct current conduction unstable.At this, even adhere to electric insulation between conductive component 13a and the conductive component 13b, owing to pass through both approaching, AC impedance reduces, and therefore the switching that utilizes AC signal to detect contact is very ideal.Also have, in order to increase the variable quantity of signal, the frequency of AC signal is preferably in more than the 1KHz.

Conductive component 13a is in case near conductive component 13b, and the AC signal that is added on the conductive component 13a just is transferred on the conductive component 13b, and is imported into signal deteching circuit 22.Signal deteching circuit 22 is with AC signal rectification, smothing filtering and be transformed into direct current signal.In case comparison circuit 23 decision signal level ratio fixed reference level height, for example with regard to the output low level signal.When the output of comparison circuit 23 was low level, control circuit 24 made light source 12 luminous with regard to making drive circuit 25 work.This just can be positively detects and driving light source 12 definitely inerrably the mode of operation of switch 13.

Fig. 4 is the circuit diagram of the concrete formation of load drive device 10 in the presentation graphs 3.Operating portion body 11 has the switch 13 that filament or light emitting diode and so on illumination light source 12 and the conductive component 13a that realizes by changing relative position cutting off or contacting and 13b constitute.

Oscillating circuit 21 has three grades of phase inverter G1-G3, and because the positive feedback that resistance or electric capacity produce, more satisfactory such as with the 10KHz hunting of frequency with the frequency more than the 1KHz, for example behind the square wave that forms TTL (transistor-transistor logic circuit) level (0V-5V), block the direct current composition and the bottoming value is that-2.5V, higher limit are+AC signal of 2.5V by capacitor C 6 and resistance R 9.The AC signal of oscillating circuit 21 outputs is added on the conductive component 13a of switch 13 by resistance R 10 and holding wire 15.

On the other hand, conductive component 13b is connected with signal deteching circuit 22 by holding wire 15.This signal deteching circuit 22 has commutation diode D1 and level and smooth filter capacitor C1, in case when Closing Switch 13 makes the AC signal input of self-oscillating circuit 21, just be transformed into direct current signal corresponding to this signal level by signal deteching circuit 22.

Comparison circuit 23 for example is made of TTL phase inverter etc., when cut-off switch 13, the detection signal of signal deteching circuit 22 compare fixed reference level when low, comparison circuit is just exported high level.On the contrary, when Closing Switch 13, detection signal compare fixed reference level when high, comparison circuit is with regard to output low level.Also have, to use difference amplifying type operational amplifier still be that all it doesn't matter for comparator to circuit 23 as a comparison.

The output of comparison circuit 23 is received in the noninverting input of operational amplifier Q1 by resistance R 1.The output of operational amplifier Q1 is connected with its anti-phase input and constitutes buffer.Also have, between this noninverting input and pressure-wire Va, be connected to capacitor C 2 with constant when very big and resistance R 2 and constitute the slow start circuit.Because the effect of this slow start circuit has relaxed the rising and the decline of comparison circuit 23 output signals, thereby prevented the rapid variation of load current, this is suppressed with regard to the deterioration that makes light source 12.

The output of operational amplifier Q1 is connected with the noninverting input of operational amplifier Q2 with diode D2 by resistance R 3.In addition, in the noninverting input of operational amplifier Q2, be connected to the monitored resistance Rm and the resistance R 11 of detection light source 12 load currents.On operational amplifier Q2, also be connected to and be used for degenerative resistance R 5, R6, R7, thereby constitute the noninverting amplifying circuit with certain amplification, this just constitutes the add circuit that the output signal of voltage signal on the monitored resistance Rm and operational amplifier Q1 is carried out addition.

The output of operational amplifier Q2 is connected on the feedback end FB of conversion adjustor Q3 (model is LM2575T-ADJ, the panasonic semiconductor corporate system) by resistance R 8.When the input IN of conversion adjustor Q3 adds non-stable DC voltage, make the pulsewidth modulation (PWM) of pulse width variation corresponding to the voltage signal that is input to feedback end FB, thereby export the power of changing from its outfan OUT.On this outfan OUT, be connected to the coil L1 and the capacitor C 3 that are used for smothing filtering, and then be connected to the diode D5 that goes up backward power into absorbing coil L1.So, owing to provide electrical power to adopt conversion adjustor Q3 for light source 12, therefore can realize the load control of little loss.

Supply with light source 12 through the electrical power that smothing filtering is crossed by drive wire 14.The load current of light source 12 flows into earth terminal by monitored resistance Rm, thereby forms the voltage signal that is proportional to load current at monitored resistance Rm two ends.In addition, be added in voltage on the light source 12, and be imported into the non-inverting input of the operational amplifier Q2 that constitutes add circuit through diode D3 by Zener diode D4 and resistance R 4 detections.

Like this, the load current of light source 12 is by monitored resistance Rm detection, and is input to the feedback end FB of conversion adjustor Q3 by operational amplifier Q2, with the supply power of control output end OUT.For example, when voltage signal on the monitored resistance Rm was improved, the input voltage of feedback end FB just increased, thereby suppresses the supply power of outfan OUT.On the contrary, when the voltage signal on the monitored resistance Rm descends, will increase the supply power of outfan OUT.This keeps constant and realizes constant current work with regard to the load current that makes light source 12.

In addition, in case open switch 13, during comparison circuit 23 output high level, the voltage signal of high level just is imported into operational amplifier Q2, thereby, force the input voltage of feedback end FB to reach maximum.So, just can not realize above-mentioned constant current work, the power that outfan OUT supplies with is almost nil, and light source 12 just extinguishes.On the other hand, in case Closing Switch 13, during comparison circuit 23 output low levels, low level voltage signal just is imported into operational amplifier Q2, thereby above-mentioned constant current work is achieved, and light source 12 just illuminates.That is to say, control the constant current work of light source 12, realize the connection of light source 12 or cut-off by console switch 13.

And then when added voltage was higher than setting on the light source 12, the voltage that is input to operational amplifier Q2 by Zener diode D4 also just increased, thereby the input voltage of feedback end FB raises, and load current is suppressed.This just forms the load voltage slicing circuit.

On the other hand, be provided with power circuit 26 from electrical power to the input IN of conversion adjustor Q3 that supply with.In this power circuit 26,,, and export non-stable DC voltage by capacitor C4 smothing filtering by the AC power process diode bridge D6 rectification that alternating current power supply PS such as source power supply provide.And then Q4 obtains constant DC and presses, and constitutes pressure-wire Va through capacitor C 5 by constant voltage adjustor (model NJM78M12FA, new Japanese wireless company limited system).

Fig. 5 is the sectional view as the three usefulness syringes 40 of one embodiment of the invention.Three usefulness syringes 40 can switch arbitrarily from the front end of jet pipe 47 fluid to three kinds of states of patient's injection water, air or water smoke (water and AIR MIXTURES) by operating two handles 43.Handle portion 41 can adorn with respect to the pipe box portion 42 that connects tubular container 48 to be taken off, thereby can implement sterilization treatment and disinfect handle portion separately.

Holding the fluid circuit and the electric wire of water, air etc. in tubular container 48, these can be connected with the feedway of outside.One operating grip 43 is moved by valve rod 44 roof pressures by the ball valve 45 of the application of force, just conducting fluid circuit 46 and to jet pipe 47 supply fluids.Also have, in the middle of fluid circuit 46, be provided with the pipe bindiny mechanism of taking off corresponding to handle portion 41 dresses.

On the other hand, keep bulb or light emitting diode and so on light source 12 in the handle portion 41, by electric wire 50, connection electrode 51, binding post 52,53 and connection electrode 54 powered lightings in the tubular container 48.Keep the fiber waveguide 30 that multifiber is formed in the jet pipe 47, and the incident end face 31a of fiber waveguide 30 is positioned at almost and light source 12 tight position contacting.In addition, the ejaculation end face 32a of fiber waveguide 30 form fluid circuits such as water lines 70 and air pipe line 71 surrounded fully circular, and radiate rotational symmetric illumination light with respect to the axle center of jet pipe 47.

Fig. 6 (a) is the end-view of jet pipe 47 shown in Figure 5, and Fig. 6 (b) is the sectional view along B1-B1 line among Fig. 5, and Fig. 6 (c) is the sectional view along B2-B2 line among Fig. 5.In Fig. 6 (a), jet pipe 47 end faces central authorities form water lines 70, and form the air pipe line 71 of concentric ring-shaped around it, and then form the ejaculation end face 32a of the fiber waveguide 30 of bigger concentric ring-shaped around it again.In Fig. 6 (b), form water lines 70 again, form three air pipe lines 71 that section is circular-arc around the water lines, around it, disposing circular fiber waveguide 30 again in Section Central.In Fig. 6 (c), it is the most central that circle shape fiber waveguide 30 is configured in the cross section in addition, and nearby dispose garden shape water lines 70 and air pipe line 71 respectively at it.Because this structure makes to realize the miniaturization of jet pipe 47.

Fig. 7 is the shape figure of expression fiber waveguide 30 shown in Figure 5, and wherein Fig. 7 (a) is its plane graph; Fig. 7 (b) is its front elevation; Fig. 7 (c) is its ground plan.Fiber waveguide 30 has the shape that the multifiber bundle is pricked, and that an end is restrainted into by grip tube 31 is a branch of, and forms circular incident end face 31a.Its other end is pricked with grip tube 32 bundles cylindraceous, forms circular ejaculation end face 32a.

Fiber waveguide 30 is stable on heating, is to use rubber elastic material, and therefore for example material soaking or lining such as silicone rubber, keep its flexible on the one hand, improved the intensity of optical fiber on the one hand greatly.Particularly in three usefulness syringes 40, between fiber waveguide 30 and jet pipe 47, be formed with air pipe line 71,,, preferably optical fiber strengthened with rubber elastic material for anti-highly compressed flow velocity like this owing to the high pressure air flow of pressure that wherein flowing up to 4Kg/cm2.In addition, optical fiber is made of glass fibre, as stalemate agent or above-mentioned coating agent material, preferably adopts heat-resisting, moisture-proof material.Fiber waveguide 30 is put into handle portion 41, may make hot and humid high-voltage device.

Fig. 8 is the part amplification sectional view of Fig. 5.Fluidic mobility status at first is described.In handle portion 41, by the fluid circuit 46 in the metal tube 46a, then arrive in the cylindric ball valve grip tube 66 of stainless steel by the right-hand fluids of sending here such as air among the figure.The ball valve 45 that rustless steel is made is under the effect of metal spring 65, and the left application of force in figure is adjacent to it tightly with seal member 45a such as silica gel, and as shown in Figure 8, under excellent valve 44 and ball valve 45 isolated states, fluid circuit 46 is in blocked state.

When stainless steel bar valve 44 right-hand move and touch ball valve 45 in figure, ball valve 45 during right-hand displacement, just produces the gap, thereby makes the fluid circuit opening in figure between with seal member 45a.So, the fluid in the ball valve grip tube 66 by these gaps arrive excellent valve 44 around, and the intercommunicating pore 68a by forming on the tubular distance piece 68 of the whole mechanism of maintaining valve imports in the fluid circuit 46 in the pipe 46b.Rod valve 44 is by spring 64 left application of force in the figure, and slides with respect to tubular distance piece 68 by garden ring 44a.

Next illustrates test bar valve 44 and ball valve 45 contacted Circuits System.Here, excellent valve 44 also plays a part conductive component 13a among Fig. 3, and ball valve 45 also plays a part conductive component 13b among Fig. 3, isolates mutually or contact by changing relative position, just plays the effect of switch 13 among Fig. 3.

In case operating grip 43, axle 43a just rotate to change an angle around inhour, and electrode clamp 61 is just right-hand mobile in figure, and by the plastic pellet part 62 that electrical insulating property the is arranged electrode 63 that bears down on one.Electrode 63 has thread structure with respect to excellent valve 44, and can be adjusted to the position of hope.When extruding electrode 63, just right-hand mobile in figure by the excellent valve 44 of spring 64 application of forces, and contact ball valve 45, thereby make the fluid circuit conducting.Ball valve 45 is electrically connected by spring 65, ball valve grip tube 66 and pipe 46a and electrode 67.So, because ball valve 45 and excellent valve 44 are all made by corrosion resistant good conductor rustless steel, therefore can detect both contact conditions definitely reliably.Also have,, therefore prevented to handle 43 electric leakages because handle 43 and excellent valve 44 by electric insulation by insulating pellet part 62.

Each electrode 63,67 is connected on the oscillating circuit 21 and signal deteching circuit 22 of load control circuit shown in Figure 3 16 by holding wire 15.Also have, in Fig. 8, circuit has been done merging, but in fact holding wire 15 is to extract in the tubular container 48 by Fig. 5 for easy to understand.

Load control circuit 16 have generation through holding wire 15 or electrode 63 etc. give the oscillating circuit 21 of the AC signal that excellent valve 44 adds, in excellent valve 44 and ball valve 45 contact back to the signal from ball valve carry out the signal deteching circuit 22 of rectification, smothing filtering, comparison circuit 23 that the output signal and the stipulated standard value of signal deteching circuit 22 compared, according to the output signal of comparison circuit 23 export the control circuit 24 of control signal, according to the control signal of control circuit 24, the drive circuit 25 of powering to light source 12 through drive wire 14 by power circuit 26 electrical power supplied.

The following describes working condition.At first when the operator did not have operating grip 43, because excellent valve 44 and ball valve 45 are isolated mutually, therefore the AC signal that is added on the excellent valve 44 was not transferred to ball valve 45, so the signal level that signal deteching circuit 22 is detected is almost nil.Comparison circuit 23 is lower than specified reference value with regard to the decision signal level, high level signal of analogy output.If the output of comparison circuit 23 is high level, because control circuit 24 can not make drive circuit 25 work, so light source 12 just can not throw light on.

Secondly, when if the operator gives as security lower handle 43 for obtaining illumination light, since excellent valve 44 near and contact with ball valve 45, connected electric current between the two, but, because wearing and tearing, the burn into oxidation of excellent valve 44 or ball valve 45, the influence of getting dirty etc., the D.C. resistance between contact can strengthen along with the increase of time.Especially as the material of excellent valve 44, ball valve 45 if the metal material of strong corrosion resistants such as titanium or rustless steel is arranged, then because the oxide-film on surface makes the direct current conduction unstable.Therefore, go up the electric current insulant, because along with both reduce, so utilize AC signal can detect the disconnection or the closure of both contacts near AC impedance even covering between excellent valve 44 and the ball valve 45.

If excellent valve 44 is near ball valve 45, the AC signal that is added on the excellent valve 44 just passes to ball valve 45, is input to signal deteching circuit 22.22 pairs of AC signals of this signal deteching circuit carry out rectification, smothing filtering is transformed into direct current signal.In case comparison circuit 23 decision signal level are higher than specified reference value, just the output analogy is a low level signal.When comparison circuit 23 was output as low level, control circuit 24 just made drive circuit 25 work, and made light source 12 illuminations.So, the operation that just can definitely inerrably detect handle 43 comes driving light source 12.

Like this, detect ball valve 45 with AC signal and whether contact with excellent valve 44, need only be according to the light on and off of light source 12 and light switch needn't be set in addition.In addition, because light source 12 will be bright when operating grip 43, this has just improved operability.Also have, contact the conductivity that causes in order to detect ball valve 45 with excellent valve 44, the two structure that can guarantee high impedance under usual isolation is ideal, such as, be preferably in air that fluid circuit 46 interior supplies have the high impedance rate, pure water and so on fluid.

Also have,, equally also be applicable to the situation of CD-ROM drive motor, thermal source even load though load is that example is represented with the light source in the above description.

The present invention can implement with other various forms without prejudice to its spirit or its principal character.Therefore only represent single example on all parts of the foregoing description, scope of the present invention is the scope described in claims, is not limited in the description.

And then be out of shape on an equal basis or similarly or change all belonging in the claim scope, all belongs to the present invention and comprise.

Claims (7)

1, a kind of circuit for detecting connecting point is characterized in that comprising: the contact mechanism that isolates or contact mutually with 2 conductive components (13a, 13b) change relative position; Generation is added on the oscillating circuit (21) of a conductive component AC signal; And the signal deteching circuit (22) that the output signal of another conductive component is carried out rectification, smothing filtering.

2, circuit for detecting connecting point according to claim 1 is characterized in that, also comprises: the comparison circuit (23) that the output signal of above-mentioned signal deteching circuit (22) and stipulated standard signal are compared; And according to the load driving circuits (25) of the output signal powering load of above-mentioned comparison circuit (23).

3, circuit for detecting connecting point as claimed in claim 2 is characterized in that: the frequency of aforementioned AC signal is more than the 1KHz.

4, circuit for detecting connecting point as claimed in claim 2 is characterized in that: it also has the slow start circuit for the rising and the decline of the output signal that relaxes above-mentioned comparison circuit (23).

5, circuit for detecting connecting point as claimed in claim 2 is characterized in that: it also comprises the conversion adjustor (Q3) of powering load.

6, the built-in dental syringe of a kind of illuminator is characterized in that it has: the lighting mechanism (12) that produces illumination light; The outside fluid of supplying with of guiding, and make its fluid passage (46) from spraying near the front end of syringe (40) body; The valve body (45) that is used for obturation or open above-mentioned fluid passage (46); One isolates or contacts above-mentioned valve body and make it change the modified gear (44) of position; One produces the oscillating circuit (21) of the AC signal that is added on above-mentioned valve body (45) or above-mentioned modified gear (44); The output signal of above-mentioned valve body (45) or above-mentioned modified gear (44) is carried out the signal deteching circuit (22) of rectification, smothing filtering; The comparison circuit (23) that the output signal and the specified reference value of above-mentioned signal deteching circuit (22) compared; And, drive the illumination driving circuit (25) of above-mentioned lighting mechanism (12) according to the output signal of above-mentioned comparison circuit (23).

7, the built-in dental syringe of illuminator as claimed in claim 6, it is characterized in that it also comprises the handle (43) that above-mentioned modified gear (44) is moved, above-mentioned valve body (45) and above-mentioned modified gear (44) are made of conductive material, and above-mentioned handle (43) and modified gear are electrically insulated from one another.

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