KR0150868B1 - Dental syringe with illuminator - Google Patents

Abstract

The present invention improves the durability of a load driving device and sterilization process capable of driving a load without malfunction by reliably detecting a contact detection circuit, a switch such as a switch, which can reliably detect a contact opening and closing of a switch, It is an object of the present invention to provide a dental syringe with a built-in lighting device which is designed to reduce the number of parts, reduce weight and size, and improve operability. It is composed of a load control circuit 16, the handpiece main body 11 is provided with a light source 12 for illumination and a switch 13 made of a conductive member (13a, 13b) to move away or in contact with each other, The load control circuit 16 includes an oscillation circuit 21 for generating an AC signal applied to the conductive member 13a through the signal line 15, and from the conductive member 13b when the switch 13 is turned on. Of A signal detection circuit 22 for rectifying and smoothing the call, a comparison circuit 23 for comparing the output signal from the signal detection circuit 22 with a predetermined reference value, and an output signal from the comparison circuit 23. A control circuit 24 for outputting a control signal based on the control signal and power supplied from the power supply circuit 26 based on the control signal from the control circuit 24 through the drive line 14. It is provided with a drive circuit 25 for supplying to the.

Description

Lighting Syringe Dental Syringe

The present invention is a built-in lighting device having a lighting control means for detecting the opening and closing of the electrical contact, the lighting driving circuit for driving the load of a light source or a motor by detecting the opening and closing of the electrical contact and the lighting device for illuminating the treatment area, etc. It relates to a dental syringe (syringe).

Conventionally, dental treatments include air turbine handpieces, micromotor handpieces, scalers, and three-way syringes for cutting teeth, removing calculus, cleaning treatment areas, and recovering debris or saliva after cutting. Various hand pieces such as syringes and vacuum syringes are used.

In the case of treating the oral cavity using such a handpiece, a work lamp installed on a medical table and the like has been lit to illuminate the oral cavity.

However, when the patient's posture or the doctor's working direction is changed, shadows appear in the oral cavity, making it difficult to observe, resulting in a decrease in workability because the position of the work lamp must be adjusted at each time.

Recently, a handpiece has been developed and put into practical use by incorporating a lamp and a light guide into the handpiece main body to emit light from the tip of the handpiece to illuminate the treatment area (Japanese Utility Model Publication No. 3-13301). Japanese Utility Model Publication No. 3-19369).

9 is a block diagram showing the electrical configuration of a conventional handpiece.

The handpiece main body 1 has a lighting light source 5 for lighting control 5 in the load control circuit 4 for driving the light source 2 while the light source 2 for lighting is built therein. The power supplied is transmitted by the drive line 3.

The lighting switch 5 is composed of an operation switch operated manually by a worker or the like by a hand or a foot, or a relay switch which is opened and closed in synchronization with the operation of a dental tool mounted on the handpiece body 1.

In a conventional syringe, a lever for opening and closing an air line and a water line and a light switch for turning on a built-in light source are separately installed, making the internal structure of the syringe complicated and miniaturization difficult.

In addition, in order to prevent infections in hospitals, disinfection treatment and high temperature and high humidity sterilization treatment should be appropriately maintained to keep the syringe clean at all times. In general, electric parts such as lighting switches have low durability against sterilization treatment and durability. These switches are often expensive and large.

In addition, in a normal treatment operation, when ejecting a fluid such as water or air into the affected part, the affected part must be illuminated. Since the fluid injection lever and the light switch are separately installed, it is difficult to operate the lever and the switch at the same time. The difficulty is that the treatment is cumbersome and complicated.

The present invention has been invented to solve the conventional problems as described above, the object of the present invention is to reliably detect the contact opening and closing of the lighting control means and the switch that can detect the contact opening and closing of the switch and the like without any malfunction A lighting drive circuit capable of driving a load is provided to improve durability against sterilization and the like, to reduce the number of parts, to reduce the weight and size, and to provide a dental syringe with a built-in lighting device which further improves operability.

1 is a block diagram showing the principle configuration of the present invention.

2 is a block diagram showing a modification of the configuration shown in FIG. 1 of the present invention.

3 is a block diagram showing an embodiment of the present invention.

4 is a circuit diagram showing a specific configuration of the load driving apparatus shown in FIG. 3 of the present invention.

Figure 5 is a cross-sectional view showing a three way syringe of an embodiment of the present invention.

6A is a sectional view of the nozzle shown in FIG. 5 of the present invention.

6B is a cross-sectional view taken along the line B1-B1 in FIG. 5 of the present invention.

6C is a cross-sectional view taken along the line B2-B2 in FIG. 5 of the present invention.

7A is a plan view showing the shape of the light guide shown in FIG. 5 of the present invention.

FIG. 7B is a front view showing the shape of the light guide shown in FIG.

Figure 7c is a bottom view showing the shape of the light guide shown in Figure 5 of the present invention.

8 is a partially enlarged cross-sectional view of the three-way syringe shown in FIG. 5 of the present invention.

9 is a block diagram showing the electrical configuration of a conventional handpiece.

* Explanation of symbols for main parts of the drawings

10: load driving device 11: handpiece body

12 light source 13 switch

16: load control circuit 30: light guide

31,32 holder 31a: incident cross section

32a: Cross-section 40: Three Way Syringe

46: fluid passage 47: nozzle

70: water pipe 71: air pipe

The present invention provides a lighting means for generating illumination light, a fluid passage for guiding the fluid supplied from the outside to eject through the vicinity of the tip of the syringe body, a valve body for closing or opening the fluid passage, A dental syringe having a built-in illumination device having displacement means for displacing the valve element by moving away from or in contact with the valve body, the illumination control controlling the lighting means by electrically detecting the contact between the valve body and the displacement means. It is characterized by having a means.

The lighting control means comprises a contact means for the two conductive members to move away from or in contact with each other by relative displacement, an oscillation circuit for generating an AC signal applied to one conductive member, and rectified from the other conductive member. It is characterized by including a signal detection circuit for smoothing (smoothness).

According to the lighting control means, an AC signal is applied to one of the two conductive members constituting the electrical contact, and a signal detection circuit is rectified and rectified from the other side to provide a smooth signal detection circuit. Even when the DC resistance of the contact increases due to contamination, the AC impedance is lowered by the approach of the two conductive members, so the contact opening and closing operation can be detected reliably.

The present invention is also characterized by having a lever for moving the displacement means, wherein the valve body and the displacement means are made of a conductive material, and the lever and the displacement means are electrically insulated.

In addition, the present invention provides a lighting means for generating illumination light, a fluid passage for guiding the fluid supplied from the outside to eject through the vicinity of the tip of the syringe body, a valve body for closing or opening the fluid passage, and the valve A dental syringe having a built-in illumination device having displacement means for displacing the valve element by moving away from or in contact with the sieve, comprising: an oscillating circuit for generating an AC signal applied to one of the valve element or the displacement means; And a signal detection circuit for rectifying and smoothing a signal from the other side of the valve body or the displacement means, and an illumination driving circuit for driving the lighting means based on an output signal of the comparison circuit. It is a dental syringe with built-in lighting device.

The illumination driving circuit includes a contact means for the two conductive members to be separated or contacted with each other by relative displacement, an oscillation circuit for generating an AC signal applied to one conductive member, and a rectified and smoothed signal from the other conductive member. A signal detection circuit, a comparison circuit for comparing the output signal from the signal detection circuit with a predetermined reference value, and a load driving circuit for supplying power to the load based on the output signal of the comparison circuit. do.

In addition, the present invention is characterized in that the frequency of the AC signal is 1kHz or more.

In addition, the present invention is characterized in that the illumination driving circuit is provided with a slow start circuit for mitigating the rise and fall of the output signal of the comparison circuit.

In addition, the present invention is characterized in that the lighting driving circuit is provided with a switching regulator (switching regulator) for supplying power to the load.

According to the above lighting driving apparatus, an AC signal is applied to one side of two conductive members constituting an electrical contact, and a signal detection circuit is provided to rectify and smooth the signal from the other side, thereby increasing DC resistance due to deterioration of the contact. Even in this case, as the two conductive members approach each other, the AC impedance is lowered, thereby making it possible to reliably detect the contact opening and closing operation of both conductive members.

Further, by comparing the output signal from the signal detection circuit with a predetermined reference value, it is possible to clearly detect the presence or absence of the contact opening and closing operation. Also, based on the comparison result, when the contact opening and closing operation is detected, the lighting driving circuit supplies power to the load of the light source and the motor. Therefore, the contact opening and closing operation can be detected reliably and the load can be driven without malfunction.

When the frequency of the AC signal is 1 kHz or more, the change in the AC impedance between the contacts due to the contact opening and closing operation increases and the amount of change in the detection signal increases, so that more reliable detection is possible.

In addition, since the lighting driver circuit includes a slow start circuit for mitigating the rise and fall of the output signal of the comparison circuit, the voltage applied to the load gradually rises or falls. As a result, abrupt fluctuations in the load current such as rush current can be alleviated, and thus adverse effects on the load can be prevented.

In addition, since the lighting driver circuit includes a switching regulator for supplying power to the load, load control with low loss can be realized.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

1 is a block diagram showing the principle configuration of the lighting control means used in the present invention.

The handpiece main body 11 is provided with a light source 12 for illumination, such as a filament lamp, a light emitting diode, and the like, and a switch 13 for lighting the light source 12 with light. The load control circuit 16 detects contact opening and closing of the switch 13 through the signal line 15, and when the switch 13 is turned on, energizes the light source 12 through the driving line 14. Light is on. Thus, by providing the switch 13 to the handpiece body 11, the operability of the treatment operation can be improved.

FIG. 2 is a block diagram showing a modification of the configuration shown in FIG. 1.

The handpiece body 11 and the load control circuit 16 are connected by three lines 17a, 17b and 17c, where 17a functions as a drive line, 17c as a signal line, and 17b as a common line.

As such, the configuration shown in FIG. 2 can reduce the number of lines as compared with the configuration of FIG. 1.

3 is a block diagram showing an embodiment of an illumination driving circuit used in the present invention.

The load driving device 10 includes a handpiece main body 11 and a load control circuit 16. The handpiece main body 11 is displaced relatively apart from each other with a light source 12 for illumination such as a filament lamp or a light emitting diode. And a switch 13 made of conductive members 13a and 13b which lose or contact.

The load control circuit 16 includes an oscillation circuit 21 for generating an AC signal applied to the conductive member 13a through the signal line 15, and from the conductive member 13b when the switch 13 is turned on. A signal detection circuit 22 for rectifying and smoothing a signal of?, A comparison circuit 23 for comparing the output signal from the signal detection circuit 22 with a predetermined reference value, and an output from the comparison circuit 23; The control circuit 24 outputting a control signal based on the signal, and the power supplied from the power supply circuit 26 based on the control signal from the control circuit 24 through the drive line 14. ) Is provided with a drive circuit 25 for supply.

Next, the operation of the above configuration will be described.

First, when the operator does not operate the switch 13, since the conductive member 13a and the conductive member 13b are separated from each other, the AC signal applied to the conductive member 13a is not transmitted to the conductive member 13b. .

Therefore, the signal level detected by the signal detection circuit 22 is almost 0V. The comparison circuit 23 determines that the signal level is lower than the predetermined reference value and outputs, for example, a high level signal. In addition, when the signal line 15 is longer, external noise tends to be mixed. However, since the comparison circuit 23 discriminates the level, noise performance is improved. If the output of the comparison circuit 23 is at a high level, the light source 12 is not turned on because the control circuit 24 does not operate the driving circuit 25.

When the operator operates the switch 13 to obtain illumination light, electrical conduction is obtained between the conductive members 13a and 13b because the conductive member 13a approaches and contacts the conductive member 13b.

However, the DC resistance of the contacts tends to increase over time due to the wear, corrosion, oxidation, and contamination of the conductive members 13a and 13b. In particular, when a highly corrosion-resistant metal such as titanium or stainless steel is used as the material of the conductive members 13a and 13b, direct current electrical conductivity becomes unstable due to the oxide film on the surface.

Therefore, even if an electrical insulator is attached between the conductive member 13a and the conductive member 13b, it is preferable to detect the contact opening and closing by using the AC signal because the AC impedance is lowered by both conductive members 13a and 13b approaching. Do.

In addition, in order to increase the amount of change in the signal, the frequency of the AC signal is preferably 1 kHz or more.

When the conductive member 13a approaches the conductive member 13b, an AC signal applied to the conductive member 13a is transmitted to the conductive member 13b and input to the signal detection circuit 22. The signal detection circuit 22 rectifies and smoothes the AC signal to convert it into a DC signal. When the comparison circuit 23 determines that the signal level is higher than the predetermined reference value, it outputs a low level signal, for example. If the output of the comparison circuit 23 is at the low level, the control circuit 24 operates the drive circuit 25 to light the light source 12. In this way, the operation of the switch 13 can be reliably detected and the light source 12 can be driven without malfunction.

4 is a circuit diagram showing a specific configuration of the load drive device 10 shown in FIG.

The handpiece body 11 includes a light source 12 for illumination, such as a filament lamp or a light emitting diode, and a switch 13 composed of conductive members 13a and 13b that move away from or contact each other with relative displacement.

The oscillation circuit 21 has three stages of inverters G1 to G3, and is oscillated at a frequency of preferably 1 Hz or more, for example, 10 Hz by positive feedback by a resistor or a capacitor. For example, a square wave of TTL (Transistor to Transistor Logic) level (0V-5V) is generated, and the DC component is cut by the capacitor C6 and the resistor R9, so that the lower limit is -2.5V and the upper limit is 2.5V. Output the signal.

The AC signal output from the oscillation circuit 21 is applied to the conductive member 13a of the switch 13 through the resistor R10 and the signal line 15.

On the other hand, the conductive member 13b is connected to the signal detection circuit 22 through the signal line 15. The signal detecting circuit 22 includes a rectifying diode D1 and a smoothing capacitor C1. When the switch 13 is turned on and an AC signal from the oscillation circuit 21 is input, the signal detecting circuit 22 receives an AC signal. Convert to a corresponding DC signal.

The comparison circuit 23 is composed of, for example, an inverter of a TTL and the like, and when the switch 13 is turned off and the detection signal of the signal detection circuit 22 is lower than a predetermined reference level, a high level is output and the switch 13 is turned on. When the detection signal is higher than the predetermined reference level, the low level is output. As the comparison circuit 23, a differential amplification type or the like may be used.

The output of the comparison circuit 23 is input to the non-inverting terminal of the operational amplifier Q1 through the resistor R1, and the output of the operational amplifier Q1 is input to the inverting terminal to form a buffer.

In addition, a capacitor C2 and a resistor R2 having a large time constant are connected between the non-inverting terminal and the voltage line Va to form a slow start circuit. The slow start circuit eases the rise and fall of the output signal from the comparison circuit 23, thereby preventing the sudden change of the load current and suppressing the deterioration of the light source 12.

The output of the operational amplifier Q1 is input to the non-inverting terminal of the operational amplifier Q2 through the resistor R3 and the diode D2, and the load current of the light source 12 is supplied to the non-inverting terminal of the operational amplifier Q2. The monitor resistor Rm to be detected and the resistor R11 are connected. The negative feedback resistors R5, R6, and R7 are connected to the operational amplifier Q2 to form a non-inverting amplifier circuit having a predetermined amplification rate, and the monitor resistor Rm and the resistor R11 are connected to the operational amplifier Q2. . Negative feedback resistors R5, R6, and R7 are connected to the operational amplifier Q2 to form a non-inverting amplifier circuit having a predetermined amplification factor. The voltage signal from the monitor resistor RM and the operational amplifier ( An adder circuit to which the signal from Q1) is added is configured.

The output of the operational amplifier Q2 is applied via the resistor R8 to the feedback terminal FB of the switching regulator Q3 (model number "LM2575T-ADJ", manufactured by National Seiko). When the unstable DC voltage is supplied through the input terminal IN, the switching regulator Q3 performs a pulse width modulation PWM to change the pulse width in response to the voltage signal input to the feedback terminal FB, thereby outputting the output terminal. Output the switched power via (OUT). The smoothing coil L1 and the condenser C3 are connected to this output terminal OUT, and a diode D5 for back electromotive force absorption of the coil L1 is connected. Thus, by using the switching regulator Q3 for supplying electric power to the light source 12, load control with low loss can be implement | achieved.

The smoothed power is supplied to the light source 12 through the drive line 14. The load current of the light source 12 flows to the ground through the monitor resistor Rm, and a voltage signal proportional to the load current is generated at both ends of the monitor resistor Rm. In addition, after the voltage applied to the light source 12 is detected by the zener diode D4 and the resistor R4, the non-inverting terminal of the operational amplifier Q2 constituting the addition circuit through the diode D3. Is entered.

As such, after the load current of the light source 12 is detected by the monitor resistor Rm, the load current of the light source 12 is input to the feedback terminal FB of the switching regulator Q3 through the operational amplifier Q2 and thus from the output terminal OUT. Supply power is controlled. For example, when the load current increases to increase the voltage signal of the monitor resistor Rm, the input voltage of the feedback terminal FB is increased, thereby suppressing the supply power from the output terminal OUT. In addition, when the voltage signal of the monitor resistor Rm decreases, the supply power from the output terminal OUT is suppressed. In addition, when the voltage signal of the monitor resistor Rm decreases, the supply power from the output terminal OUT increases. In this way, a constant current operation for maintaining a constant load current of the light source 12 is realized.

In addition, when the switch 13 is turned off and the comparison circuit 23 outputs a high level signal, a high level voltage signal is input to the operational amplifier Q2 so that the input voltage of the feedback terminal FB is forcibly increased. do. Then, since the above-described constant current operation does not work, the power supply from the output terminal OUT becomes almost zero, so that the light source 12 does not light up. On the other hand, when the switch 13 is turned on and the comparison circuit 23 outputs a low level signal, the low level voltage signal is input to the operational amplifier Q2 to operate the above-described constant current operation so that the light source 12 is turned on. do. In this way, the constant current operation of the light source 12 is controlled by the operation of the switch 13 so that the light source 12 is turned on or off.

In addition, when the applied voltage of the light source 12 is higher than the predetermined value, the voltage input to the operational amplifier Q2 through the zener diode (D4) is increased to increase the input voltage of the feedback terminal (FB) to suppress the load current Works in the direction of Thus, the voltage limiter circuit of the load is formed.

On the other hand, a power supply circuit 26 for supplying power to the input terminal IN of the switching regulator Q3 is provided. In this power supply circuit 26, AC power supplied from AC power supply such as commercial power is rectified by a diode bridge (D6) and smoothed by a capacitor (C4) to output an unstable DC voltage. have. In addition, a stable DC voltage is obtained by a constant voltage regulator (model number "NJM78M12FA", manufactured by Nippon Wireless Co., Ltd.) Q4, and the DC voltage is supplied to the voltage line Va through the capacitor C5.

5 is a cross-sectional view showing a three way syringe 40 of an embodiment of the present invention.

The three-way syringe 40 blows fluid toward the affected part by arbitrarily switching three states of water, air, or mist (mixing of water and air) through the tip of the nozzle 47 by operating two levers 43. You can.

Since the handle portion 41 can be detachably attached to the socket portion 42 to which the tube 48 is connected, the handle portion 41 can be sterilized or disinfected.

In the tube 48, a fluid line through which water, air, and the like flow and an electric wire are stored, which are connected to an external supply device. When the lever 43 is operated, the ball valve 45 which is held is moved by the valve rod 44, so that the fluid line 46 is conducted so that the fluid is supplied toward the nozzle 47. In addition, the fluid pipe 46 is provided with a pipe connecting mechanism corresponding to the attachment / detachment of the handle portion 41.

On the other hand, the handle portion 41 has a light source 12, such as a lamp, a light emitting diode, or the like is built in, the light source 12 is a wire 50 installed in the tube 48, the connection electrode 51, the connection pin 52 ), And the lamp is turned on by supplying electric power through the connecting pin 53, the connecting electrode 54, and the like. The nozzle 47 has a built-in light guide 30 made of a plurality of optical fibers, the incidence end surface 31a of the light guide 30 is positioned so as to be in close contact with the light source 12. Further, the light emission section 32a of the light guide 30 is formed in a circular ring shape so as to surround a fluid pipe such as the water pipe 70 or the air pipe 71, and rotates about the axis center of the nozzle 47. Emits symmetrical illumination light.

FIG. 6A is a sectional view of the nozzle 47 shown in FIG. 5, FIG. 6B is a sectional view taken along the line B1-B1 in FIG. 5, and FIG. 6C is a sectional view taken along the line B2-B2 in FIG.

In FIG. 6A, the water pipe path 70 is formed at the center of the cross section of the nozzle 47, and the air pipe path 71 is formed in a concentric annular shape around the light guide 30. An emission cross section 32a is formed.

In FIG. 6B, the water pipe passage 70 is formed at the center of the end face, and the air guide 71 is formed in three places in the shape of a circular arc around the light guide. 30) is arranged.

In FIG. 6C, a circular light guide 30 is disposed at the center of the cross section, and a water pipe passage 70 and an air pipeline 71 in the shape of a circular ring are arranged around the cross section. By such a configuration, the nozzle 47 can be miniaturized.

FIG. 7 illustrates the shape of the light guide 30 shown in FIG. 5, wherein FIG. 7A is a plan view, FIG. 7B is a front view, and FIG. 7C is a bottom view.

The light guide 30 has a shape in which a plurality of optical fibers are bundled. At one end, an incidence end surface 31a, which is bundled together by a holder 31, is formed, and at the other end thereof is a cylindrical holder 32. Bundled by this, an exit end face 32a of a circular ring shape is formed.

The light guide 30 is impregnated or coated with a rubber-elastic material having a heat resistance, for example, silicone rubber, thereby improving the strength of the optical fiber while maintaining flexibility.

In particular, in the three-way syringe 40, since an air line 71 is formed between the light guide 30 and the nozzle 47, high pressure air of about 4 kg / cm 2 flows, so that the flow rate can withstand this flow rate. It is preferable to reinforce the optical fiber with a material having rubber elasticity. In addition, since the optical fiber is made of glass fiber or the like, an autoclave sterilization at high temperature and high humidity with the light guide 30 attached to the handle part 41 using an adhesive or a coating material having heat resistance and moisture resistance. Is making it possible.

FIG. 8 is a partially enlarged cross-sectional view of the three-way syringe shown in FIG. 5.

First, the flow of the fluid will be described. In the handle portion 41, a fluid such as air sent from the right side in FIG. 8 passes through the fluid pipe 46 in the metal pipe 46a, and then reaches the cylindrical stainless steel ball valve holder 66. . Since the stainless steel ball valve 45 is held to the left in the drawing by the metal spring 65 and is in close contact with the sealing material 45a such as silicone rubber, the valve rod 44 is the ball valve 45 as shown in FIG. Fluid management 46 is occluded in a state away from

When the stainless steel valve rod 44 moves to the right side in FIG. 8 and comes into contact with the ball valve 45, the ball valve 45 is displaced to the right side in the drawing, and a gap is formed between the sealing member 45a and the fluid pipe ( 46) is opened. Then, the fluid in the ball valve holder 66 reaches around the valve rod 44 through this gap and then passes through the communication hole 68a formed in the spacer 68 supporting the entire valve mechanism. It is introduced into the fluid passage 46. The valve rod 44 is tethered to the left side in the figure by the spring 64 and slides in the spacer 68 through the zero ring 44a.

Next, the circuit system which detects the contact of the valve rod 44 and the ball valve 45 is demonstrated.

The valve rod 44 corresponds to the conductive member 13a of FIG. 3, and the ball valve 45 corresponds to the conductive member 13b of FIG. 3, respectively. The switch 13 shown in FIG. It functions as).

When the lever 43 is operated, the angular displacement in the counterclockwise direction about the axis 43a causes the holder 61 to be displaced to the right in FIG. 63). Since the electrode 63 is screwed to the valve rod 44, it can be adjusted to a desired position. When the electrode 63 is depressed, the valve rod 44 supported by the spring 64 is displaced to the right in FIG. 8 to be in contact with the ball valve 45 to conduct the fluid pipe 46. The ball valve 45 is electrically connected to the electrode 67 through the spring 65, the ball valve holder 66, and the pipe 46a. Since the ball valve 45 and the valve rod 44 are made of stainless steel which is a conductive material having good corrosion resistance, the contact between them can be reliably detected. In addition, since the lever 43 and the valve rod 44 are electrically insulated by the spherical member 62 having electrical insulation, electrical leakage to the lever 43 is prevented.

Each of the electrodes 63 and 67 is connected to the oscillation circuit 21 and the signal detection circuit 22 of the load control circuit 16 shown in FIG. 3 via the signal line 15. In addition, in FIG. 8, although an electric circuit is shown for easy understanding, the actual signal line 15 is drawn out in the tube 48 shown in FIG.

The load control circuit 16 includes an oscillation circuit 21 for generating an AC signal applied to the valve rod 44 through the signal line 15 or the electrode 63, the valve rod 44 and the ball valve ( The signal detection circuit 22 rectifies and smoothes the signal from the ball valve 45 when 45 is in contact, and the comparison circuit comparing the output signal from the signal detection circuit 22 with a predetermined reference value ( 23, a control circuit 24 for outputting a control signal based on the output signal from the comparison circuit 23, and a power supply circuit 26 based on the control signal from the control circuit 24. A driving circuit 25 is provided to supply the supplied electric power to the light source 12 through the driving line 14.

Next, the operation of the above configuration will be described.

First, when the operator lever 43 is not operated, since the valve rod 44 and the ball valve 45 are separated from each other, the AC signal applied to the valve rod 44 is not transmitted to the ball valve 45. Therefore, the signal level detected by the signal detection circuit 22 is almost 0V. In this case, the comparison circuit 23 determines that the signal level is lower than the predetermined reference value and outputs, for example, a high level signal. If the output of the comparison circuit 23 is at a high level, the control circuit 24 does not operate the driving circuit 25, so that the light source 12 is not turned on.

When the operator pushes the lever 43 to obtain the illumination light, the valve rod 44 approaches and contacts the ball valve 45, so that electric conductivity can be obtained between them.

However, the DC resistance of the contacts tends to increase over time due to the effects of wear, corrosion, oxidation, contamination of the valve rod 44 or the ball valve 45. In particular, when a metal having high corrosion resistance such as titanium or stainless steel is used as the material of the valve rod 44 and the ball valve 45, direct current electrical conductivity becomes unstable due to the oxide film on the surface. Therefore, even if an electric insulator is attached between the valve rod 44 and the ball valve 45, the contact impedance can be detected by using an AC signal because the AC impedance is lowered by both approaches.

When the valve rod 44 approaches the ball valve 45, an AC signal applied to the valve rod 44 is transmitted to the ball valve 45 and input to the signal detection circuit 22. The signal detection circuit 22 rectifies and smoothly converts an AC signal into a DC signal. When the comparison circuit 23 determines that the signal level is higher than the predetermined reference value, it outputs a low level signal, for example. If the output of the comparison circuit 23 is at the low level, the control circuit 24 operates the drive circuit 25 to turn on the light source 12. By doing so, the operation of the lever 43 can be reliably detected and the light source 12 can be driven without malfunction.

As such, the contact of the ball valve 45 and the valve rod 44 is detected using an AC signal to turn on the light source 12, thereby eliminating the need to separately install an illumination switch. Moreover, since the light source 12 is lighted every time the lever 43 is operated, operability is improved. In addition, since the electrical conductivity due to the contact between the ball valve 45 and the valve rod 44 is detected, a structure capable of ensuring high resistance in a state where both are separated is preferable. It is preferable to supply a fluid having a high specific resistance, such as air or pure water.

Although the example which used the light source as a load was shown in the said Example, it is similarly applicable also when driving a motor, a heater, etc.

The present invention can be implemented in other various forms without departing from its spirit or main features. Therefore, the above-described embodiments are merely examples in all respects, and the scope of the present invention is shown in the claims, and is not limited to the specification text.

Moreover, all the deformation | transformation and a change which belong to the same range as a claim are considered within the scope of this invention.

As described above, according to the syringe of the present invention, by applying a DC voltage or an alternating voltage between the valve body and the displacement means to electrically detect the presence or absence of both, the lighting switch for turning on the light source is controlled. Since there is no need to install it separately, the number of parts can be reduced and the configuration can be simplified. In addition, since it is not necessary to use low-durability electrical parts, the entire syringe can be sterilized, sterilized, or the like. In addition, the presence or absence of a fluid ejection operation such as water or air can be easily detected, so that the light can be illuminated in synchronization with the fluid ejection operation, thereby improving the operability of the treatment operation.

In addition, by providing a lever for moving the displacement means, the force required for operating the valve body can be reduced. In addition, since the valve body and the displacement means are made of a conductive material, the contact between them can be reliably detected. In addition, since the lever and the displacement means are electrically insulated, electricity flowing through the detection circuit never leaks into the lever, so that an electric shock of an operator can be reliably prevented.

Claims (3)

A lighting means for generating illumination light, a fluid passage for guiding the fluid supplied from the outside and ejecting it through the vicinity of the tip of the syringe body, a valve body for closing or opening the fluid passage, and away from the valve body. Or an illumination device built-in dental syringe having displacement means for abutting and displacing the valve body, the apparatus comprising: lighting control means for electrically detecting the contact between the valve body and the displacement means and controlling the lighting means; Illuminating device built-in dental syringe, characterized in that one. 2. The lighting apparatus built-in type according to claim 1, further comprising a lever for moving the displacement means, wherein the valve body and the displacement means are made of a conductive material, and the lever and the displacement means are electrically insulated. Dental syringe. An illuminating means for generating illumination light, a fluid passage for guiding the fluid supplied from the outside and ejecting it through the vicinity of the tip of the syringe body, a valve body for closing or opening the fluid passage, and away from the valve body; Or a dental syringe having a built-in illumination device having displacement means for abutting and displacing the valve body, comprising: an oscillating circuit for generating an alternating signal applied to one side of the valve body and the displacement means; A signal detection circuit for rectifying and smoothing a signal from the other side of the displacement means, a comparison circuit for comparing the output signal from the signal detection circuit with a predetermined reference value, and the illumination means based on the output signal of the comparison circuit. Lighting device built-in dental syringe, characterized in that provided with a lighting drive circuit for driving.