JPH0215455Y2 - - Google Patents

Description

[Detailed description of the invention] [Field of industrial application] The present invention relates to a device for preventing internal contamination of a handpiece, and in particular, to a dental handpiece used for tooth cutting and a drive device connected to the handpiece. This invention relates to a device for preventing internal contamination of a handpiece, which is ideal for preventing contamination of the entire dental unit.

[Conventional technology]

In recent years, dental handpieces used for tooth cutting have been designed so that the tip cutting tool is rotated at high speed by pressurized air from an appropriate external pressurized air supply source. When the handpiece is in use, running water from an appropriate external water source is poured into the cutting tip to prevent the tip cutting tool from heating up and to wash away tooth debris.

This allows tooth cutting to be carried out in a short period of time without causing pain to the patient.
If the tip cutting tool rotates at high speed when the handpiece is pulled out of the mouth, there is a risk of an unexpected accident.

Therefore, traditionally, after tooth cutting is completed,
A proposal has been made to stop the rotation of the tip cutting tool by discontinuing the supply of pressurized air, thereby stopping the rotation of the handpiece when the handpiece is pulled out of the mouth, thereby preventing unforeseen accidents. It is said that

However, in the conventional method described above, when stopping the rotation of the tip cutting tool, the supply of pressure air is simply stopped, so the rotation of the cutting tool is not stopped instantaneously, and the tip cutting tool is stopped due to inertia. will rotate for a while and then stop.

Therefore, due to the inertial rotation of the cutting tool, the blades in the cutting tool holding portion at the tip of the handpiece rotate idly, causing a suction action toward the inside of the handpiece, which damages the cutting tool and the hand in its vicinity. The water adhering to the outside of the piece enters the inside of the handpiece as dirty water containing tooth debris, saliva, blood, germs, etc.

Therefore, in order to prevent this, for example,
A suction prevention device for a dental air turbine has been developed as disclosed in Japanese Patent Publication No. -76642.

This device stops the inertial rotation of the cutting tool caused by stopping the supply of pressurized air by temporarily supplying pressurized air from the exhaust side, that is, by reverse feeding.

[Problem that the invention attempts to solve]

However, with the above-described suction prevention device, there is a risk that a suction effect similar to that described above may occur when the vehicle is reversed. In addition, since the pressure gas is sent back using an air storage accumulator, the supply of pressure gas ends instantaneously, and the pressure inside the handpiece immediately becomes the same as atmospheric pressure, causing the cutting tool holding part and It is not possible to completely prevent the above-mentioned sewage from entering through holes for installing cutting tools and other gaps.

As a result, not only the inside of the handpiece becomes contaminated, but also the contamination spreads to the entire drive device connected to the handpiece via the air supply circuit and water supply circuit, and the entire dental unit including the drive device. There are widespread inconveniences.

If the contamination is limited to the handpiece itself, it is possible to eliminate the contamination by disinfecting the handpiece with gas for a long period of time, but once the contamination is present in the drive unit or When it comes to dissemination to dental units including
In fact, it becomes impossible to eliminate the contamination, and the handpiece is always kept in an unsanitary condition.

Therefore, when treating another patient again, contaminated bacteria such as type B virus, etc.
There is a risk of infection to this patient, and if this is done repeatedly, the germs will be passed on to a large number of people.

Therefore, this idea was developed so that when the cutting tool stops rotating,
This is stopped instantly and the inside of the handpiece is maintained at high pressure for a predetermined period of time, thereby preventing dirty water from entering through the holding part of the cutting tool and other gaps. It is an object of the present invention to provide a device for preventing internal contamination of a handpiece, which can prevent contamination of the entire dental unit including the device.

[Means for solving problems]

In order to solve the above-mentioned problems, the configuration of this invention is such that while the cutting tool at the tip of the handpiece is rotated when pressurized air is being supplied to the air supply circuit, pressurized air is simultaneously supplied to the air supply circuit and exhaust circuit. The cutting tool is prevented from rotating while the cutting tool is being supplied, and the inside of the handpiece is maintained at a high pressure state for a predetermined period of time. In an internal contamination prevention device for a handpiece formed to prevent external sewage, etc. from entering the handpiece through a gap, a first air supply circuit is provided in the air supply circuit.
A pilot switching valve, a second pilot switching valve, and a solenoid switching valve are disposed in the exhaust circuit, and a third pilot switching valve is provided in the exhaust circuit to select whether the exhaust circuit is connected to the air supply circuit continuously or discontinuously. A valve is provided, the first pilot switching valve;
When pilot pressure is being supplied to the second pilot switching valve and the third pilot switching valve, pressure is supplied to the air supply circuit, and at the same time, pressure is supplied to the first pilot switching valve and the third pilot switching valve. When the pilot pressure is released, when the accumulated pilot pressure is being supplied to the second pilot switching valve, and when the solenoid switching valve is energized, pressure is simultaneously supplied to the air supply circuit and the exhaust circuit. It is characterized by being formed so that it is supplied with.

〔Example〕

Hereinafter, the present invention will be explained based on the illustrated embodiments.

The drawing shows an embodiment of the present invention, in which a hand piece 1 is connected to the tip of an air supply circuit 2 and to the tip of a water supply circuit 3. A base end of an exhaust circuit 4 is connected to the hand piece 1.

A cutting tool 1a is detachably and rotatably held at the tip of the hand piece 1, and the pressure through the air supply circuit 2 causes the cutting tool 1a to rotate at high speed at the holding portion, and the subsequent pressure is It is designed to be exhausted to the outside via the exhaust circuit 4.
When the cutting tool 1a rotates at high speed, water from the water supply circuit 3 is injected into the cutting tool 1a.

A pressurized air supply source 5 is connected to the base end of the air supply circuit 2. The pressurized air supply source 5 may be any source such as an air pump or a compressor, as long as it can supply a predetermined pressure air to the air supply circuit 2. Further, the air supply circuit 2 has an auxiliary air supply circuit 2a formed to be branched in the middle, and the auxiliary air supply circuit 2a and the air supply circuit 2 each have a pressure reducing valve with a relief. 6a, 6, and the air pressure in the hand piece side circuit is set to be the optimum air pressure for rotationally driving the cutting tool 1a. A pressure gauge 7 is attached to the air supply circuit 2, so that whether or not the pressure inside the circuit 2 is maintained at a set pressure can be visually checked from the outside.

Further, a first pilot switching valve 8 is disposed in the air supply circuit 2, and a first pilot switching valve 8 is provided in the auxiliary air supply circuit 2.
A solenoid switching valve 9 and a second pilot switching valve 10 are disposed at a. The auxiliary air supply circuit 2a is connected to the pilot switching valve 10.
are connected to a pilot switching valve 8 disposed in the air supply circuit 2 and a third pilot switching valve 11 disposed in the exhaust circuit 4, respectively. Note that the auxiliary air supply circuit 2a is
The pilot switching valve 10 is connected to the solenoid switching valve 9 by a side passage 2b.

Each of the pilot switching valves 8, 10, and 11 is configured to be switched by the supply of pilot pressure from the pilot pressure source 12, and one pilot switching valve 10 is Pilot circuit 13 connected to pressure source 12
It is connected to an auxiliary pilot circuit 13a which branches off from the auxiliary pilot circuit 13a, and is configured to be switched by the pilot pressure from the auxiliary pilot circuit 13a.

A check valve 14 is disposed in the auxiliary pilot circuit 13a to prevent the pilot pressure from returning in the direction of the pilot pressure source 12, and a reservoir tank 15 is provided in the auxiliary pilot circuit 13a. is attached, so that pilot pressure can be stored in the reservoir tank 15.

The pilot circuit 13 and the auxiliary pilot circuit 13a are provided with exhaust ports 16, 16a each having a variable throttle.

The pilot switching valve 8 has an air supply position 8a and a ventilation position 8b, and when it is in the air supply position 8a, the air supply circuit 2 receives pressurized air from the auxiliary air supply circuit 2a. When the venting position is switched by the action of the pilot pressure and is in the venting position,
This allows the pressure air from the air supply circuit 2 that has passed through the pressure reducing valve 6 with relief to flow toward the air supply circuit 2 on the hand piece 1 side.

Furthermore, the pilot switching valve 10 is in the shutoff position 10a during normal times, blocking communication with the auxiliary air supply circuit 2a, and when pilot pressure is added, it becomes the communication position 10b, thereby blocking the communication of the auxiliary air supply circuit 2a. It is formed to allow communication.

Furthermore, the pilot switching valve 11 is
During normal times, in the air supply position 11a, the pressurized air in the auxiliary air supply circuit 2a is allowed to flow toward the exhaust circuit 4, and when pilot pressure is added,
As the exhaust position 11b, the exhaust circuit 4
is connected to the muffler 17.

The solenoid switching valve 9 is normally in the air supply position 9a, and the pressure in the auxiliary air supply circuit 2a that has passed through the pressure reducing valve with relief 6a is transferred to the hand piece 1 via the pilot switching valve 10.
When the solenoid is energized, it becomes the communication position 9b so that the pressure in the auxiliary air supply circuit 2 is supplied to the handpiece 1 side via the side passage 2b. is formed.

The base end of the water supply circuit 3 is connected to a water supply source 18, and has a check valve 19 in the middle to prevent the water supplied to the handpiece 1 side through the water supply circuit 3 from flowing backward. are doing. In other words, the water supply circuit 3 is prevented from being contaminated by sewage flowing in from the handpiece 1 side due to the backflow of water in the water supply circuit 3.

In the embodiment of the present invention formed as described above, when the handpiece 1 is used, the pressurized air supply source 5
The pressurized air from the air supply circuit 2 and the auxiliary air supply circuit 2a
At the same time, the pilot pressure from the pilot pressure source 12 is transferred to each pilot switching valve 8,1.
0 and 11. In addition, water supply source 1
Flowing water from 8 is supplied into the handpiece 1 via the water supply circuit 3.

As a result, the pressure in the auxiliary air supply circuit 2a is
Although the flow is blocked by switching the pilot switching valves 8 and 11, the pressure in the air supply circuit 2 is
The cutting tool 1 is supplied into the handpiece 1 through the ventilation position 8b of the pilot switching valve 8.
This means that a will be rotationally driven. The pressure air after rotationally driving the tip cutting tool 1a flows into the exhaust circuit 4, passes through the exhaust position 11b of the pilot switching valve 11, and is discharged from the muffler 17 to the outside.

Next, when the rotation of the tip cutting tool 1a is stopped, the pilot pressure in the pilot circuit 13 is discharged to the outside through the exhaust port 16.

As a result, the pilot switching valves 8 and 11
will return to the air supply positions 8a and 11a, respectively. On the other hand, the pilot switching valve 10 in the auxiliary air supply circuit 2a is temporarily in the communication position 10b due to the accumulated pressure in the reservoir tank 15. Therefore, the pressure in the auxiliary air supply circuit 2a is simultaneously supplied to the air supply circuit 2 and the exhaust circuit 4 at the same pressure via the pilot switching valves 8 and 11 which have been switched, and the cutting tool The rotation of 1a will be stopped instantaneously.

When the rotation is stopped, the hand piece 1 is filled with pressurized air via the air supply circuit 2 and the exhaust circuit 4, and the pressurized air is blown out to the outside through the gap in the holding portion of the cutting tool 1a. , and is attached to the cutting tool 1a. This prevents so-called dirty water from entering the inside of the handpiece 1.

Note that even if the supply of running water from the water supply source 18 is stopped when the rotation is stopped, since the check valve 19 is provided, the backflow of the running water will not be caused, and the handpiece 1
There is no need to worry about sewage entering the interior from the tip and flowing back.

After the rotation stop continues for a while, the pilot switching valve 10 in the auxiliary air supply circuit 2a is returned to the cutoff position 10a, but at this time, the solenoid switching valve 9 is energized and switched to the communication position 9b. In particular, auxiliary air supply circuit 2
The pressure air in the cutting tool 1a is passed through the pilot switching valves 8 and 11 through the side passage 2b without passing through the pilot switching valve 10, and the rotation of the cutting tool 1a is maintained in a stopped state. The interior will be filled with pressure.

Note that the exhaust port 1 communicating with the reservoir tank 15
If the variable throttle is adjusted in step 6a, it is possible to arbitrarily set the time during which the rotation of the cutting tool 1a continues to be stopped and the time during which the hand piece 1 is filled with pressurized air. Furthermore, the solenoid switching valve 9 can continue to stop the rotation and fill the internal pressure when desired, regardless of the adjustment of the variable throttle of the exhaust port 16a.

[Effect of idea]

As described above, according to the present invention, the rotation of the cutting tool at the tip of the handpiece is stopped instantaneously, which prevents the suction phenomenon from the tip of the handpiece toward the inside, and the inside of the handpiece is filled with pressurized air for a predetermined period of time. Then, the pressure is blown out to the outside from the gap in the cutting tool holding part at the tip of the handpiece and other holes for mounting the cutting tool or other gaps, so that tooth debris, saliva, etc. attached to the cutting tool are removed. This has the advantage that dirty water containing blood, germs, etc. does not enter the inside of the handpiece.

As a result, it is possible to prevent contamination of not only the inside of the handpiece but also the device for driving the handpiece and the entire dental unit including the device.

In addition, when disinfecting the handpiece, it is now sufficient to disinfect only the outside, which eliminates the technical difficulties of disinfecting the outside of the handpiece and the long time constraints associated with gas disinfection. This has the effect of making it possible to disinfect the handpiece easily and in a short time.

[Brief explanation of the drawing]

The drawing is a circuit diagram showing an embodiment of the present invention. 1...handpiece, 1a...cutting tool, 2...
Air supply circuit, 3...Water supply circuit, 4...Exhaust circuit, 5
...Pressure air supply source, 8...First pilot switching valve, 9...Solenoid switching valve, 10...Second pilot switching valve, 11...Third pilot switching valve, 18...Water supply source, 19 ……non-return valve.

Claims (1)

[Scope of utility model registration request] While the cutting tool at the tip of the handpiece is rotated when pressure air is supplied to the air supply circuit, the rotation of the cutting tool is prevented when pressure air is simultaneously supplied to the air supply circuit and the exhaust circuit. and, the interior of the handpiece is maintained at a high pressure state for a predetermined period of time, and external sewage or the like enters into the handpiece through a gap formed at the cutting tool holding portion at the tip of the handpiece and at the tip of the handpiece. In a device for preventing internal contamination of a handpiece, the air supply circuit is provided with a first pilot switching valve, a second pilot switching valve, and a solenoid switching valve. A third pilot switching valve is disposed in the circuit to select whether the exhaust circuit is connected to the air supply circuit continuously or discontinuously, and the first pilot switching valve, the second pilot switching valve, and the third pilot switching valve are connected to each other. When pilot pressure is being supplied to the pilot switching valve No. 3, pressure air is being supplied to the air supply circuit, and the pilot pressure to the first pilot switching valve and the third pilot switching valve is released. , so that when the accumulated pilot pressure is being supplied to the second pilot switching valve and when the solenoid switching valve is energized, pressure is simultaneously supplied to the air supply circuit and the exhaust circuit. A handpiece internal contamination prevention device characterized by: