JPH0716498B2 - Internal contamination prevention device for medical handpieces - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention is described above in a handpiece main body having a treatment tool such as a cutting tool that operates using air as a driving source, such as a dental air turbine handpiece. An air supply passage for supplying compressed air for driving the treatment tool, an exhaust passage for discharging air exhausted in the handpiece body to the outside, and a water supply passage for supplying pressurized water for cleaning and cooling the oral cavity. A medical handpiece equipped with, when using the handpiece in the oral cavity or body, externally contaminated blood,
The present invention relates to a device for preventing internal contamination of a medical handpiece, which is configured to prevent saliva, shavings, sewage, bacteria, etc. from entering the body of the handpiece and further various units connected thereto. .

(Prior Art) This type of internal pollution control device is used to prevent AIDS, hepatitis B, herpes, influenza, tuberculosis, etc., which accompany the entry of various contaminants as listed above into the body of the handpiece. Although it aims to prevent nosocomial infections,
As internal pollution preventing devices developed aiming at such a purpose, those described in, for example, Japanese Utility Model Publication No. 61-185408 and Japanese Patent Application Laid-Open No. 62-127047 are conventionally known. ing.

The former device instantaneously stops the operation of the air-driven treatment tool by simultaneously supplying compressed air with the same pressure as the air supply passage to the exhaust passage when the handpiece stops operating, and Is kept at a high pressure to prevent invasion of contaminants from the outside, while a check valve is provided in the water supply passage to shut off the water supply at the same time when the turbine stops operating.

In the latter device, an airtight cover is provided near the pressure fluid (air) discharge port of the head of the handpiece, and the pressure fluid is introduced into this cover so that the internal pressure of the handpiece head does not become negative. In this way, that is, the internal pressure of the handpiece head portion is maintained at a pressure higher than the atmospheric pressure to prevent invasion of contaminants from the outside.

(Problem to be Solved by the Invention) Among the above-mentioned conventional internal pollution control devices, the former one is configured such that only the check valve is interposed in the air supply passage, and therefore the water supply is stopped when the turbine stops operating. Even if the water is shut off, if water remains in the water supply passage downstream of the check valve, and the remaining water is contaminated, the residual contaminated water will be used by the patient during the next treatment. However, there is a drawback that the desired pollution prevention cannot be achieved reliably and sufficiently.

In addition, the latter not only cannot sufficiently prevent contamination in the water supply passage, but also attach a cover to the head of the handpiece and install a new air supply passage to prevent negative pressure in the cover. It is necessary to provide such a device, and as a result, there is an inevitable drawback that the handpiece head portion is increased in size and the structure is complicated.

The present invention has been made in view of the above circumstances, and can reliably and sufficiently prevent internal contamination of the handpiece including the water supply passage and the entire unit connected to the handpiece. Effective utilization and simple structure,
Another object of the present invention is to provide a device for preventing internal contamination of a medical handpiece that can be easily configured in a small size.

Another object of the present invention is to make it possible to prevent pollution in the water supply system more effectively.

(Means for Solving the Problems) In order to achieve the above object, an internal contamination preventing device for a medical handpiece according to the present invention is provided with the above-mentioned treatment tool in a handpiece body having an air-driven treatment tool. An air supply passage for supplying compressed air through the air supply on / off valve for driving, an exhaust passage for discharging air exhausted in the handpiece body to the outside through the exhaust on / off valve, and pressurized water in the handpiece body. In a medical handpiece including a water supply passage for supplying the water, a flow rate in a range where the treatment tool is not driven for a set time from the signal input based on the input of an operation stop signal or an operation start signal to the handpiece. And / or an air supply passage contamination prevention means for supplying air, and an exhaust passage contamination prevention means for maintaining a high pressure in the exhaust passage for a set time from the signal input. Stop means, and the air supply passage pollution preventing means is a bypass passage which is provided with a throttle valve and a bypass opening / closing control valve and is connected in parallel to the air supply opening / closing valve. It is characterized in that it is a bypass passage with a throttle valve connected in parallel to the on-off valve.

Further, it is preferable that the water supply passage of the above-mentioned device is provided with a water supply passage contamination preventing means that operates so as to discharge the residual water to the outside. As means for preventing contamination of the water supply passage, means for closing the water supply on-off valve after a lapse of a set time from the input of the operation stop signal of the handpiece, means for temporarily introducing compressed air branched from the air supply passage into the water supply passage Any one of the means for instantaneously injecting pressurized water into the water supply passage from the water storage portion provided in the water supply passage is selectively configured.

Further, the apparatus having the above-mentioned configuration may be provided with drip water prevention means that operates based on an operation stop signal of the water supply passage contamination prevention means.

(Operation) According to the internal contamination prevention device for a medical handpiece having the above-mentioned configuration, when the normal treatment use is finished and the operation of the handpiece is stopped, the operation stop signal is input. Based on the signal input, air having a flow rate and / or pressure within a range in which the treatment tool is not driven for a set time is supplied into the handpiece body, and the exhaust passage is kept at a high pressure for the set time. Thus, the air passage inside the handpiece body is maintained at a high pressure state, and contaminants are prevented from entering the handpiece body from the outside. On the other hand, the residual water in the water supply passage is positively discharged to the outside on the basis of the input of the operation stop signal, so that the contaminated water is prevented from remaining in the water supply passage.

Also, after discharging the contaminated residual water in the water supply passage,
By activating the water drop prevention means, water drops drop from the end of the water inlet of the handpiece body, so-called "bottom drop".
Can be prevented.

(Embodiment) An embodiment of the present invention will be described in detail below with reference to the drawings.

1 and 2 are operation system diagrams of an internal contamination preventing device for a medical handpiece according to an embodiment of the present invention. In each of these drawings, 2 is a handpiece body, and a head portion of the handpiece body 2 is shown. 2a is equipped with a rotary treatment tool 1, such as an air driven type, that is, an turbine driven type cutting machine. Reference numeral 3 denotes an air supply passage, which supplies compressed air for driving the treatment tool 1 into the main body 2 of the handpiece, and a base end portion of the air supply passage 3 is added via a pressure reducing valve 7. In addition to being connected to the compressed air supply source 8, a supply air opening / closing valve 9 which is opened / closed by pilot pressure is interposed in the middle thereof. Reference numeral 10 is a pilot pressure control valve. This pilot pressure control valve 10 is switched to two positions by turning ON / OFF an electric signal a from the controller 11, and the pilot pressure is controlled via the passage 3a branched from the air supply passage 3 as described above. By operating the air supply on-off valve 9, the air supply on-off valve 9 is opened and closed.

Reference numeral 4 denotes an exhaust passage. The exhaust passage 4 guides the air exhausted in the handpiece body 2 to a position separated from the handpiece body 2 by an air distance, and a silencer 12 to the outside.
The exhaust on-off valve 13 whose opening and closing is controlled by pilot pressure is installed in the middle of the exhaust gas. 14
Is a pilot pressure control valve. This pilot pressure control valve 14 is switched to two positions by turning ON / OFF the electric signal b from the controller 11, and the pilot pressure is applied to the exhaust on-off valve 13 via the branch passage 3a. By doing so, the exhaust on-off valve 13 is opened and closed.

Reference numeral 5 denotes a water supply passage, which supplies pressurized water into the handpiece main body 2, and its base end is connected to a pressurized water supply source 18 via a pressure reducing valve 15 and a main valve 16. At the same time, a water supply on-off valve 16 whose opening and closing is controlled by pilot pressure is interposed. Reference numeral 19 is a pilot pressure control valve. This pilot pressure control valve 19 is switched between two positions by turning ON / OFF the electric signal d from the controller 11, and the pilot pressure is applied to the feed water opening / closing valve 6 via the branch passage 3a. By doing so, the water supply on-off valve 6 is opened and closed.

In the dental air turbine handpiece having the basic structure as described above, the bypass passage 20 is formed in parallel with the air supply on-off valve 9 in the middle of the air supply passage 3, and the bypass passage 20 is formed.
A throttle valve 21 and a control valve 22 are provided on the valve 20. The throttle valve 21 supplies the air in a flow rate and / or pressure range where the treatment tool 1 is not driven to the air supply passage 3 and the handpiece body 2 via the bypass passage 20 when the air supply on-off valve 9 is closed. The throttle valve is set to
22 is controlled to an open / close 2 position by an electric signal c output from the controller 11 based on the input of an operation signal for stopping the operation to the handpiece, and its closed state is set for a set time t1 from the input of the operation signal. A timer circuit 23 for holding is provided. As described above, based on the input of the operation signal of the operation stop to the handpiece, the handpiece main body 2 is operated for a set time t1 from the input of the operation signal.
An air supply passage contamination preventing means for supplying the air in the above range to the inside of the head portion 2a and maintaining the inside of the head portion 2a at a high pressure is constituted.

Further, a bypass passage 25 with a throttle valve 24 is formed in parallel with the exhaust opening / closing valve 13 in the middle of the exhaust passage 4, and a pilot pressure control valve 14 for controlling the opening / closing of the exhaust opening / closing valve 13 is provided. Switching to the open position Electric signal b
Is provided for a set time t2 from the input of the operation signal described above. As described above, based on the input of the operation signal for the operation stop to the handpiece, the exhaust from the inside of the handpiece body 2 is performed through the bypass passage 25 with the throttle valve 24 for a set time t2 from the input of the operation signal. As a result, an exhaust passage contamination prevention unit that also serves as a sudden stop unit for the treatment tool 1 that keeps the exhaust passage 4 at a high pressure is configured.

Further, the application of the switching electric signal (d) to the closed position for the pilot pressure control valve 19 for controlling the opening / closing of the feed water opening / closing valve 6 is performed for a set time from the input of the operation signal described above.
A timer circuit 27 is provided after the elapse of t3, whereby the water supply is opened and closed by holding the water supply for a set time t3 from the operation signal input based on the input of the operation signal of the operation stop to the handpiece. A water supply passage contamination preventing means for discharging the contaminated water remaining in the water supply passage 5 downstream of the valve 6 to the outside of the handpiece is configured.

Furthermore, in the middle of the water supply passage 5, the water supply on-off valve 6
A pump 28 for preventing dripping water is communicatively connected to a location near the downstream of the. This dripping water preventing pump 28 has a piston-like valve 28b fitted in its pump chamber 28a, as clearly shown in FIG.
The pump chamber 28a in the free state via the spring 28c.
While urged to move in the direction of increasing the internal volume,
By applying a pilot pressure to the back chamber 28d through the pilot pressure control valve 19, the piston-shaped valve 28b is configured to move in the direction of reducing the volume inside the pump chamber 28a against the spring 28c. By this, based on the input of the operation signal of the deactivation to the handpiece,
When the water supply opening / closing valve 6 is closed after a delay of a set time t3 from the input of the operation signal, that is, by switching the pilot pressure control valve 19 that controls the operation stop of the water supply passage pollution preventing means to the closed position, the back chamber 28d The pilot-like valve 28b in the state shown in FIG.
Is moved in a direction to increase the volume in the pump chamber 28a by the elastic return force of the spring 28c, and a part of the residual water in the water supply passage 5 is removed as shown in FIG. A drip prevention means for preventing water from dropping from the tip of the water supply passage 5 by being sucked into the pump chamber 28a is configured.

Next, regarding the operation of the above configuration, a timing chart of the electric signals a to d shown in FIG. 4 and the electric signals a
The operation will be described with reference to the timing chart of FIG. 5, which shows the operating states of the three on-off valves 9, 13, 6 and the control valve 22 and the pump 28 which operate in correspondence with .about.

When the operation signal for starting the operation of the handpiece is input via the controller 11, the electric signals a and d are turned on, the pilot pressure control valves 10 and 19 are switched to the open position, and the pilot pressure is supplied via the branch passage 3a. The air supply on / off valve 9, the water supply on / off valve 6 and the back chamber 28d of the pump 28 are actuated to open the on / off valves 9 and 6, and the pump 28 is moved as shown in FIG. 3 (a).
It becomes the state of. At this time, the pilot pressure control valve 14 is kept in the closed position, the exhaust opening / closing valve 13 is also left open, and
16 is open.

FIG. 1 shows the above state. In this state, compressed air is supplied from the pressurized air supply source 8 through the air supply passage 3 into the handpiece main body 2 to drive the treatment tool 1, and the hand The exhausted air in the body 2 of the piece 2
The compressed water is supplied to the outside through the water supply passage 18 and the pressurized water is supplied from the pressurized water supply source 18 through the water supply passage 5. By the above,
The handpiece is actuated for any desired length of time to provide the desired treatment.

Next, when the operation stop operation signal of the handpiece is input via the controller 11, the electric signal a is turned off and the air supply on-off valve 9 is closed via the pilot pressure control valve 10, and at the same time, the electric signal is changed. d is the time set by the timer circuit 23
Control valve 22 opens after t1 is turned on for the above set time.
Over the time t1, air having a flow rate and / or pressure within a range in which the treatment tool 1 is not driven is supplied into the handpiece body 2 through the bypass passage 20 with the throttle valve 21 and the air supply passage 3, and the electric signal b Turns on for a set time t2 by the timer circuit 26, the exhaust opening / closing valve 13 is closed via the pilot pressure control valve 14, and the bypass passage 25 with the throttle valve 24
The exhaust passage 4 is maintained in a high pressure state for the set time t2 by switching the exhaust to the exhaust.

As described above, the treatment tool 1 suddenly stops, the inside of the head portion 2a of the handpiece body 2 is kept at a pressure higher than the atmospheric pressure, and external contaminants are removed from the handpiece body 2, the air supply passage 3, and the air supply passage 3. Intrusion into the exhaust passage 4 is prevented.

On the other hand, from the input of the above operation stop operation signal, the timer circuit
The electric signal d remains ON until the time set by t27 has passed,
Moreover, the water supply on-off valve 6 is kept open, and the pressurized water is supplied into the handpiece body 2 through the water supply passage 5,
The contaminated water remaining in the passage portion of the water supply passage 5 inside the handpiece body 2 is discharged to the outside of the handpiece, so that the water supply passage 5 is prevented from being contaminated.

Then, after the set time t3 has passed, the electric signal d is turned off.
Then, the water supply on-off valve 6 is automatically closed via the pilot pressure control valve 19 and the pilot pressure acting on the back chamber 28d of the pump 28 is released. Therefore, as shown in FIG. As described above, the volume in the pump chamber 28a is increased, whereby the pump suction force acts on the residual water in the water supply passage 5 and a part of the residual water is sucked into the pump chamber 28a, Drops of water drops are prevented.

FIG. 2 shows the above state. In this state, invasion of contaminants into the handpiece body 2, the air supply passage 3, and the exhaust passage 4 is prevented, and the contaminated water remains in the water supply passage 5. The contamination of the handpiece as well as the units connected to it is prevented.

In the timing charts shown in FIG. 4 and FIG. 5, the OFF timing of the electric signals c, b, d and the corresponding operation timings of the on-off valve 9, the control valve 22, and the on-off valves 13, 6 are indicated by dotted lines. It may be set to.

FIG. 6 is an operation system diagram showing another embodiment of the present invention. The difference from the above embodiment is that the pilot pressure control valve 1
Eliminating the use of 0,14,19, each open / close valve for air supply, exhaust, water supply 9,1
All the solenoid valves 3 and 6 are solenoid valves, and these solenoid on-off valves 9, 13, 6 and the control valve 22 are configured to be directly controlled to be opened / closed by turning ON / OFF the electric signals a, b, d and c. 28 is also a plunger pump that electrically operates via a timer circuit 29 that operates by receiving a command signal from the controller 11, and the opening and closing operation timings thereof are the same as those shown in FIG. Since the configuration is the same as that shown in FIGS. 1 and 2, the same reference numerals are given and detailed description thereof will be omitted.

FIG. 7 is another embodiment of the present invention showing an operation system diagram of another example of the pollution preventing means of the water supply passage 5, which is an opening / closing 2 position by turning ON / OFF the electric signal d in the middle of the water supply passage 5. A water storage section 17 is communicatively connected to a position near the downstream side of the water supply on-off valve 6 which is opened and closed by the pilot pressure of the pilot pressure control valve 19 which is switched to. As shown in FIG. 8, in this water storage section 17, the piston valve 17b fitted in the water storage chamber 17a has a spring.
In the free state, it is urged to move in a direction to increase the volume in the water storage chamber 17a via 17c, and this state, that is, the eighth
A pilot pressure control valve that stores water in the water storage chamber 17a in the state shown in FIG. 1 (a) and that can be switched between two open / close positions by turning on / off the electric signal e output from the controller 11 via the timer circuit 30. When the pilot pressure is applied to the back chamber 17d through the branch passage 3a of the air supply passage 3 as the valve 31 is switched to the open position, the piston valve 17b resists the spring 17c, as shown in FIG. 8 (b). As a result, the stored water in the water storage chamber 17a is transferred to the water supply passage 5
The residual contaminated water in the water supply passage 5 is instantaneously injected into the handpiece to be discharged to the outside of the handpiece to prevent the water supply passage 5 from being contaminated.

FIG. 9 is a timing chart in the case of the embodiment shown in FIG. 7, in which the water supply on-off valve 6 is closed simultaneously with the input of the operation signal for stopping the operation of the handpiece, and the setting by the timer circuit 30. The residual water is extruded by the injection of the stored water in the water storage chamber 17a over the time t4.

FIG. 10 is also another embodiment of the present invention showing an operation system diagram of another example of the pollution preventing means of the water supply passage 5, which is located in the vicinity of the downstream of the water supply opening / closing valve 6 in the middle of the water supply passage 5. The tip of the branch passage 3b of the air supply passage 3 is directly connected via the throttle valve 32, and the controller 11 is connected to the branch passage 3b.
ON of the electric signal f output from the
An electromagnetic opening / closing valve 34, which is switched to the open / closed 2 position by being turned off, is provided. Therefore, as shown in the timing chart of FIG. 11, the water supply opening / closing valve 6 is closed simultaneously with the input of the operation signal for stopping the operation of the handpiece. At the same time, the timer circuit 33
The compressed air branched from the air supply passage 3 for a set time t5 is temporarily introduced into the water supply passage 5 through the throttle valve 32, and the residual contaminated water in the water supply passage 5 is pushed out to the outside of the handpiece. Therefore, the water supply passage 5 is configured to be prevented from being contaminated. In the embodiment shown in FIG. 10, the third
Drip water prevention means as shown in the figure, that is, a water drop prevention pump 28 is connected, and this pump 28 is a controller.
It operates with the pilot pressure sent from 11 through the pilot pressure control valve 36 which is switched to the open / close 2 position via the electric signal g output for a set time t6 by the timer circuit 35, but this is omitted. You may.

In each of the embodiments shown in FIGS. 7 and 10, the air supply passage contamination preventing means and the exhaust passage contamination preventing means are omitted. However, these means are configured as shown in FIGS. 1 and 2. Naturally, the pollution prevention means of is provided.

Although not shown, it goes without saying that a check valve and / or a cleaning liquid supply passage may be installed in the water supply passage 5.

Further, in each of the above-mentioned embodiments, the contamination preventing means of each of the passages 3, 4, and 5 is shown to be configured to be operated based on the input of the operation signal for stopping the operation of the handpiece. It may be configured to operate based on the input of a start operation signal. Figures 12 and 13 show the first
Timings corresponding to FIGS. 4 and 5 in the case of the embodiment shown in FIG. 2 and FIG. 2 when the respective pollution preventing means are operated based on the input of the operation signal for starting the operation of the handpiece. It is a chart.

(Effect of the Invention) As is apparent from the above description, according to the present invention, the air supply passage is based on the input of the operation stop signal after the use of the handpiece or the operation start signal before the use of the handpiece. The inside of the handpiece main body extending from the exhaust passage to the exhaust passage and the passage portion connected to the handpiece main body can be maintained at a high pressure within the range where the treatment tool is not driven, and the invasion of contaminants from the outside can be surely prevented, and in the water supply passage, The contaminated residual water can be discharged to the outside to prevent infection caused by the use of the contaminated residual water. As a result, the effect of preventing contamination of the inside of the handpiece and the entire unit connected thereto can be reliably and sufficiently achieved. Moreover, a structure for enlarging the head portion of the handpiece body is not required, and a predetermined contamination preventing action can be exerted by controlling the flow of air and water in each passage of the existing handpiece. This has the effect of making it easier to reduce the size and size.

Further, when the water drop prevention means is arranged in parallel in the water supply passage where it is technically most difficult to prevent pollution, it is possible to more effectively prevent pollution in the water supply system.

[Brief description of drawings]

1 and 2 are operation system diagrams showing an embodiment of the present invention, FIGS. 3 (a) and 3 (b) are enlarged vertical cross-sectional views showing drip water preventing means, and FIGS. 4 and 5 are operations. 6 is an operation system diagram showing another embodiment of the present invention, and FIGS. 7 and 10 are other embodiments of the present invention, respectively, showing a contamination preventing means of a water supply passage. A central operation system diagram, FIGS. 8 (a) and 8 (b) are enlarged vertical cross-sectional views of the water storage portion which is a constituent element in the case of the embodiment shown in FIG. 7, and FIG. 9 is shown in FIG. FIG. 11 is a timing chart for explaining the operation of the embodiment, FIG. 11 is a timing chart for explaining the operation of the embodiment shown in FIG. 10, and FIGS. 12 and 13 are FIGS. 6 is a timing chart corresponding to FIGS. 4 and 5 for explaining another operation in the case of the embodiment shown in FIG. (Explanation of symbols) 1 ... Treatment tool, 2 ... Handpiece body, 3 ... Air supply passage, 4 ... Exhaust passage, 5 ... Water supply passage, 6 ... Water supply opening / closing valve, 9 ... Air supply opening / closing Valve, 13 ... Exhaust on-off valve, 17 ... Water storage part, 20, 25 ... Bypass passage, 21, 24 ... Throttle valve.

Claims (3)

[Claims] 1. A supply for supplying compressed air into a handpiece body (2) having an air-driven treatment tool (1) through an air supply on-off valve (9) for driving the treatment tool (1). The air passage (3), the exhaust passage (4) for exhausting the air exhausted in the handpiece body (2) to the outside through the exhaust opening / closing valve (13), and the pressurized water in the handpiece body (2). In a medical handpiece provided with a water supply passage (5) for supplying, based on an input of an operation stop signal or an operation start signal to the handpiece, a set time (t ₁ ) from the signal input
The air supply passage contamination prevention means for supplying air with a flow rate and / or pressure in a range in which the treatment tool (1) is not driven, and the exhaust passage (for a set time (t ₂ ) from the signal input. 4) an exhaust passage pollution preventing means for keeping the inside pressure high, and the supply passage pollution preventing means is provided with a throttle valve (21) and a bypass opening / closing control valve (22). 9 is a bypass passage (20) connected in parallel, wherein the exhaust passage contamination prevention means is a bypass passage (25) with a throttle valve (24) connected in parallel to the exhaust opening / closing valve (13). An internal contamination prevention device for medical handpieces. 2. A water supply passage contamination preventing means which operates so as to discharge the residual water in the water supply passage (5) to the outside, the water supply passage contamination preventing means being based on the input of an operation stop signal to the handpiece. , Means for closing the water supply on-off valve (6) after a lapse of a set time (t ₃ ) from the signal input, and compressed air branched from the air supply passage (3) to the water supply passage (5)
It is any one of a means for temporarily introducing into the water supply means and a means for instantaneously injecting pressurized water into the water supply passage (5) from a water storage section (17) provided in the water supply passage (5). 1. An internal contamination prevention device for a medical handpiece according to 1. 3. The internal contamination prevention device for a medical handpiece according to claim 2, further comprising a drip water prevention means which operates in response to an operation stop signal of the water supply passage contamination prevention means.