JP7845900B2 - Dental Unit - Google Patents

Description

This disclosure relates to a dental unit equipped with a water supply device for supplying water used by patients during treatment, etc.

Dental units equipped with various facilities used during dental treatment are fitted with a water dispenser that automatically supplies water to a cup for patients to rinse their mouths. In recent years, due to the impact of the novel coronavirus, aerosols generated during dental treatment, such as when using a turbine for cutting or scaling, have become a concern.
As countermeasures, measures have been taken to improve the suction power of the vacuum itself and to aspirate more aerosols by using an extraoral vacuum in combination. However, depending on how the handpiece is applied, the scattering angle may widen, and some aerosols inevitably remain.
If these unavoidable aerosols end up in the water in a cup placed in a water dispenser, there is a risk of infection.

Furthermore, from the perspective of infection prevention, Patent Documents 1 and 2 disclose a technique for forming an air curtain between the practitioner and the patient.

Japanese Unexamined Patent Publication No. 53-122293 Japanese Patent Application Publication No. 10-028696

Conventional air curtain formation devices produce loud noises during air supply, potentially causing anxiety and stress to patients.

This disclosure aims to provide a dental unit that can suppress the mixing of aerosols into the water in a cup placed in a water supply device using an air curtain, while also suppressing the noise level during air supply.

This application discloses a dental unit having a water supply device, wherein the water supply device includes an air outlet that emits air toward a cup-holding area, and the air outlet has multiple outlets for emitting air, and the dental unit emits air from the multiple outlets.

Multiple outlets are arranged at intervals along a virtual line where their center of gravity forms a ring. When considering a circle with the same area as the area enclosed by the ring, the diameter of this circle is 50 mm or more. The system may also include control means to control the air discharge flow rate at the air outlet between 3 L/min and 20 L/min.

The control mechanism may be configured to emit air from the air outlet when a cup is placed on the cup-holding area, and to stop the air outlet from emitting air at all other times.

According to this disclosure, it is possible to suppress infection by forming an air curtain to prevent aerosols from mixing with the water in the cups placed in the water supply device, while also reducing the noise level during air supply.

Figure 1 is an external view of dental unit 1. Figure 2 is an external perspective view of the water supply device 10. Figure 3 is a perspective view of the water supply device 10 from another angle. Figure 4 shows the air outlet 15 as viewed from the cup holder 12 side.

The following description of this disclosure is based on the embodiments shown in the drawings. However, this disclosure is not limited to these embodiments.

1. Structure of the Dental Unit Figure 1 shows an external perspective view of a dental unit 1 in one configuration. The dental unit 1 comprises a base 2, a patient chair 3, a lighting unit 4, a doctor's unit 5, an assistant unit 6, and a water supply and drainage unit 7.

1.1. Base The base 2 is positioned below the patient chair 3 and serves as the base for the patient chair 3. The base 2 has an outer casing formed by a housing, and various control devices are enclosed inside the housing. Examples of the control devices included here include a hydraulic circuit for raising and lowering, tilting and standing up the patient chair 3, and a hydraulic control means for controlling the hydraulic circuit. Accordingly, a foot switch 2a is provided on the back side of the base 2 of the patient chair 3. The practitioner can operate this foot switch 2a or the operation switches on the control panel of the doctor unit 5 to issue commands to the hydraulic control means, thereby controlling the hydraulic circuit to raise and lower, tilt and stand up the patient chair 3.

1.2. Patient Chair In this embodiment, the patient chair 3 comprises a seat 3a, a backrest 3b, a headrest 3c, a leg rest 3d, and a footrest 3e. These parts of the patient chair are well known and are not particularly limited.

1.3. Lighting Unit The lighting unit 4 is equipped with a lighting head 4a attached via an arm 4b that can move and rotate with a high degree of freedom using a universal joint or the like, so that the inside of the patient's mouth can be accurately illuminated when performing treatment.

1.4. Doctor Unit The doctor unit 5 is located on the side of the patient chair 3 opposite to the assistant unit 6, and has a workbench 5a equipped with various instruments and switches required by the practitioner. The workbench 5a has a work surface on its upper surface, and a group of handpieces 5b used by the practitioner during treatment are housed in a holder. Examples of handpieces included in the group of handpieces include air turbines, micromotors, scalers, syringes, etc. An operation panel may be provided on the workbench 5a, on which various operation switches are arranged, allowing for operations such as tilting and raising/lowering the patient chair 3, switching the lighting head 4a on and off, and operating and stopping the handpieces.
Furthermore, the workbench is supported by an arm that allows it to move and rotate, enabling it to move and rotate in accordance with the practitioner's movements, thereby improving convenience.

1.5. Assistant Unit The assistant unit 6 is located on the opposite side of the patient chair 3 from the doctor unit 5 and is primarily equipped with instruments used by the assistant. The assistant unit 6 consists of a hanger section 6a supported by an arm, from which various instruments are suspended. Examples of suspended instruments include vacuums, saliva ejectors, syringes, and other handpieces.

1.6. Water supply and drainage unit The water supply and drainage unit 7 is located on the same side as the assistant unit 6 on the side of the patient chair 3 and is equipped with a spittoon 7a and a water supply device 10.

The spittoon 7a is a bowl-shaped structure designed to drain water spit out from the patient's mouth after rinsing during or after treatment. The saliva and water expelled into the spittoon 7a are then drained through a drain trap in the water unit.

The water supply device 10 automatically supplies water to a cup C used by the patient for gargling and holds the cup C. In this configuration, the water supply device 10 also includes an air outlet 15 that forms an air curtain. The water supply device 10 will be described in detail below.

2. Water supply device Figure 2 is a perspective view focusing on the area around the water supply device 10, and Figure 3 is a perspective view showing the water supply device 10 viewed from below, with the air outlet 16 visible.
As can be seen from Figures 2 and 3, the water supply device 10 has a water supply section, a cup receiving section 12, an ultrasonic sensor 13, a photoelectric sensor 14, and an air discharge section 15.

2.1. Water Supply Section The water supply section is the part that supplies water to cup C, and has a water supply pipe (not shown) and a water inlet 11 provided at its end. The water supply section is also equipped with a solenoid valve (not shown) that switches between supplying and stopping water. That is, water flowing through the water supply pipe flows out from the water inlet 11 and is poured into cup C. The water supply and stopping are switched by the solenoid valve. The operation of the solenoid valve for this switching is performed by a control means (not shown).

The control means are not particularly limited here, but for example, one example is a system in which a central operator performs calculations in a RAM (RAM) as a work area based on a program stored in a memory means such as ROM and data received from various sensors equipped in the dental unit 1, and outputs the calculation results to control each part of the dental unit 1.

2.2. Cup Receiving Section The cup receiving section 12 is the part on which the cup C is placed and which holds the cup C, which is filled with water, until the patient picks it up. The shape of the cup receiving section 12 is not particularly limited and can be any known shape, as long as it can hold the cup C.

2.3. Ultrasonic Sensor The ultrasonic sensor 13 has an oscillating unit that emits ultrasonic waves toward the cup receiving unit 12 and a detection unit that detects the ultrasonic waves that have been reflected back. In this embodiment, the ultrasonic sensor 13 is positioned near the water inlet 11. By processing the ultrasonic waves detected by the detection unit as data in the control means, the water level of the water poured into cup C is detected, and the water supply is started and stopped.

2.4. Photoelectric Sensor The photoelectric sensor 14 has a light-emitting unit that emits infrared rays so as to cross directly above the cup holder 12, and a light-receiving unit that detects the infrared rays that have been reflected back. In this embodiment, as shown in Figure 2, the photoelectric sensor 14 is positioned opposite the side of the cup C when the cup C is placed. The presence or absence of the cup C is determined by processing the infrared rays received by the light-receiving unit as data in the control means. That is, if the infrared rays emitted from the light-emitting unit are reflected by the cup C and received by the light-receiving unit, it is determined that the cup C is present, and if the infrared rays are not received by the light-receiving unit, it is determined that the cup C is not present.

2.5. Air discharge section [Form of the air discharge section]
The air outlet 15 is the part that emits air. As can be seen from Figures 1 to 3, the air outlet 15 in this embodiment is arranged to surround the water inlet 11 and is configured to emit air toward the cup holder 12, as shown by the straight dotted arrow in Figure 3. Therefore, in this embodiment, the air outlet 15 is annular, and the air curtain formed by the air emitted from it is cylindrical, with the cup C placed inside this cylindrical air curtain. This prevents aerosols, dust, and airborne debris from outside the air curtain from mixing with the cup C and the water stored inside it.

Figure 4 shows a view of the air outlet 15 from the cup holder 12 side. As described above, air is emitted from the air outlet 15 to form a cylindrical air curtain that encloses the cup C. To achieve this, the air outlet 15 in this embodiment has multiple hole-like outlets 16, which are spaced apart along a ring-shaped imaginary line (K in Figure 4), as can be seen in Figures 3 and 4. This allows the air to reach around the cup C while suppressing the amount of air used to form the air curtain and thus reducing noise.
According to the inventor's findings, forming the air outlet with an annular slit resulted in increased noise during air discharge and insufficient air thrust to the cup holder 12, leading to inadequate function as an air curtain. In contrast, these problems were solved by arranging multiple hole-shaped outlets 16 as in the present embodiment. Particularly given the nature of a dental unit, it is essential to avoid causing any anxiety or stress to the patient, and loud noise is one of the causes, making it important to suppress the noise level. Here, the specific noise level varies depending on the situation, but it is preferably 55 dB or less, and more preferably 52 dB or less, at the headrest 3c of the patient chair 3.

To enhance the air curtain function while suppressing noise levels, it is effective to appropriately set the airflow velocity emitted from the air outlet 15. A specific flow velocity of 15 m/s to 40 m/s is preferable. Here, since the flow velocity itself is related to the airflow path and flow rate, it is preferable to satisfy the following conditions as a more specific configuration for achieving this.

The air discharge flow rate from the entire air discharge section 15 is preferably 3 L/min to 20 L/min, and more preferably 4 L/min to 15 L/min. The means for adjusting the flow rate are not particularly limited, but for example, it can be done by placing a graduated needle valve in the piping to the air discharge section. By obtaining the discharge flow rate for a given air pressure in advance and adjusting the needle valve's scale in accordance with the air pressure, an appropriate discharge flow rate can be obtained. Alternatively, a flow meter can be installed in the piping to the air discharge section, and the flow rate adjustment valve can be operated by a control means based on the measured value.

Multiple injection ports 16 are arranged at intervals along a virtual line (K in Figure 4) that forms a ring, with the centroid (center if the injection port is circular) of each port being at the center of gravity. When considering a circle with the same area as the area enclosed by this ring K, it is preferable that the diameter of this circle be 50 mm or more. There is no upper limit, but it is preferably 100 mm or less. If the ring K is a circle, the diameter shown by D in Figure 4 is preferably 50 mm or more, and there is no particular upper limit, but it is preferably 100 mm or less.
It is preferable that ring K is a circle, but it does not need to be a perfect circle; it is sufficient if it is approximately a circle.

The size of each injection port 16 is preferably such that, from the viewpoint of Figure 4, if it is circular, its diameter is 1 mm or more and 10 mm or less, and if it is not circular from the viewpoint of Figure 4, its area is preferably 0.78 ^mm² or more and 78.5 ^mm² or less.
Furthermore, there may be multiple outlets 16. More preferably, there may be four or more. In this case, the outlets 16 may be spaced equally apart, but the arrangement of the outlets 16 may be made more densely packed so that more outlets 16 are placed on the side closer to the patient chair 3 where aerosols are more likely to be generated.

The supply of air to each outlet 16 is not particularly limited, but it is preferable to connect them to the same air supply source that supplies air to the handpiece. This allows air to be supplied by the existing compressor used in the dental unit, eliminating the need for a new air supply source and keeping costs low.

[Starting and stopping air discharge]
Air is discharged from the air discharge unit 15 by supplying and stopping air to the air discharge unit 15. This can be done by, for example, installing a switch on any part of the dental unit 1 (e.g., the doctor's unit 5), which allows the practitioner to discharge and stop air as desired.

In addition to this, or instead, the supply and cessation of air to the air outlet 15 may be performed automatically depending on the presence or absence of the cup C. That is, when the cup C is placed on the cup holder 12, air is discharged from the air outlet 15, and when the cup C is not placed on the cup holder 12, the discharge of air from the air outlet 15 is stopped.
While the specific configuration for this purpose is not particularly limited, the presence or absence of a cup C in the cup receiving section 12 is detected by the photoelectric sensor 14 as described above. The control means, upon receiving the signal from the photoelectric sensor 14, performs calculations to determine the presence or absence of cup C, and then instructs the solenoid valve, which is installed in the piping that supplies air to the air outlet section 15, to open or close according to the determination. This eliminates the need for the practitioner to perform individual tasks for forming the air curtain, thus reducing the practitioner's workload.

1. Dental unit 2. Base 3. Patient chair 4. Dental lighting 5. Doctor's unit 6. Assistant unit 7. Water supply and drainage unit 10. Water supply device 15. Air outlet

Claims (1)

A dental unit having a water supply system,
The water supply device is
It is equipped with an air outlet that emits air towards the area where the cup is placed,
The aforementioned air outlet unit has a plurality of outlets for discharging air,
It emits air from multiple nozzles,
Each of the multiple injection ports is hole-shaped, and the lines connecting the centroids of the holes form a ring, and these ports are spaced apart along an imaginary line.
Dental unit.