Patent Description:
Conventionally, there is known a technique that detects an abnormality in a handpiece. For example, <CIT> and <CIT> disclose a technique which uses a temperature detecting member attached to a handpiece to determine whether or not a thermal abnormality is present in the handpiece. Further technological background can be found in <CIT> and <CIT>.

In the technique described in the patent literatures described above, since the temperature detecting member is integrated with the handpiece, the temperature detecting member will suffer from fast degradation during the use of the handpiece.

The present disclosure has been accomplished in view of the aforementioned problems, and an object thereof is to provide a detection tool capable of determining whether or not a thermal abnormality is present in a handpiece for a long period of time and a detection method using the detection tool.

According to the present disclosure, a detection tool that detects the temperature of air is provided. The detection tool includes a detection section that detects a temperature of air released from the air turbine handpiece, and a main body that includes a surface. The detection section is provided on the surface so as to allow the air turbine handpiece to be brought close to the detection section.

In accordance with the invention, a detection method for detecting a temperature of air as defined in claim <NUM> is provided. The detection method includes driving the air turbine handpiece to operate for a predetermined time and bringing an air turbine handpiece close to a detection tool that detects the temperature of air within a predetermined distance.

The foregoing and other objects, features, aspects and advantages of the present disclosure will become apparent from the following detailed description of the present disclosure when taken in conjunction with the accompanying drawings.

The present disclosure will be described in detail with reference to the drawings. In the drawings, the same or corresponding portions are denoted by the same reference numerals, and the description thereof will not be repeated.

An application example of a detection tool (thermal gauge) <NUM> will be described with reference to <FIG> is a schematic diagram illustrating an application example of the detection tool <NUM>.

The detection tool <NUM> is a card-type temperature detection tool that detects the temperature of air released from an air turbine handpiece <NUM>. When an operator such as a dentist grasps a grip <NUM> of the air turbine handpiece <NUM> and brings a head <NUM> of the air turbine handpiece <NUM> close to a detection section <NUM> of the detection tool <NUM>, a thermo-sensitive material <NUM> provided in the detection section <NUM> may change color in response to the temperature of air released from the head <NUM> of the air turbine handpiece <NUM>.

The thermo-sensitive material <NUM> provided in the detection section <NUM> of the detection tool <NUM> changes color when the temperature of the detected air is equal to or higher than a predetermined temperature. When the temperature of air released from the air turbine handpiece <NUM> that is brought close to the detection tool <NUM> by the operator is equal to or higher than the predetermined temperature, the thermo-sensitive material <NUM> provided in the detection section <NUM> changes color in response to the temperature of the air.

Thus, the operator may use the detection tool <NUM> to determine whether or not a thermal abnormality is present in the air turbine handpiece <NUM>. Further, since the detection tool <NUM> is separated from the air turbine handpiece <NUM>, it is possible to use the detection tool <NUM> for a long period of time to determine whether or not a thermal abnormality is present in the air turbine handpiece <NUM> without suffering from degradation during the use of the air turbine handpiece <NUM>.

The configuration of the air turbine handpiece <NUM> will be described with reference to <FIG>. The air turbine handpiece <NUM> is a handpiece to be used by a dentist and is configured to rotate a cutting tool <NUM> attached to the head <NUM> by a driving force generated by air. Hereinafter, the configuration of the air turbine handpiece <NUM> will be described in detail.

<FIG> is a side view illustrating the air turbine handpiece <NUM>. <FIG> is a longitudinal sectional view illustrating a main part of the air turbine handpiece <NUM>. <FIG> is a partial cross-sectional view illustrating a main part of the air turbine handpiece <NUM>. <FIG> is a transverse cross-sectional view illustrating a main part of the air turbine handpiece <NUM>. The cross-sectional view in <FIG> is obtained by cutting the air turbine handpiece <NUM> along line IV-IV in <FIG>.

The air turbine handpiece <NUM> includes a grip <NUM> to be grasped by an operator such as a dentist during treatment. A base end of the grip <NUM> is provided with a connection member 2a which is connected to a supply tube <NUM> for supplying air. A distal end of the grip <NUM> is connected to the head <NUM> via a neck 2b. The cutting tool <NUM> is detachably mounted to the head <NUM>.

The head <NUM> is integrated with a shaft member <NUM> which is connected to the distal end of the grip <NUM> and a cylindrical housing <NUM> which is configured to house the cutting tool <NUM> and a driving member <NUM> configured to drive the cutting tool <NUM>. A rotation axis 41a of the cylindrical housing <NUM> is arranged perpendicular or substantially perpendicular to a central axis 40a of the shaft member <NUM>. The rotation axis 41a corresponds to a central rotation axis of the cutting tool <NUM>.

The shaft member <NUM> of the head <NUM> has a small diameter portion 40b which is sized and shaped so as to allow the shaft member <NUM> to be inserted into the distal end of the cylindrical grip <NUM>. The shaft member <NUM> is provided with a plurality of through holes to fluidly communicate a rear end surface 40c on the side of the grip <NUM> with an inner wall surface of the cylindrical housing <NUM>. The plurality of through holes include air supply passages <NUM> to <NUM> configured to supply pressurized air to the driving member <NUM>, and exhaust passages <NUM> and <NUM> configured to discharge pressurized air from the driving member <NUM>.

The air supply passages <NUM> to <NUM> are connected to an air supply pipe <NUM> that extends inside the grip <NUM> in the longitudinal axis direction of the grip <NUM> from the connection member 2a to which the supply tube <NUM> is connected. The air supply passage <NUM> communicates with a communication member <NUM> of the air supply pipe <NUM> which is drilled in the shaft member <NUM>. The air supply passages <NUM> and <NUM> communicate with the communication member <NUM> via communication passages 72a and 73a drilled in the shaft member <NUM>. Thus, the pressurized air supplied from the air supply pipe <NUM> is introduced into the cylindrical housing <NUM> through the air supply passages <NUM> to <NUM>, respectively.

The base ends of the gas supply passages <NUM> and <NUM> open to the outer circumferential surface of the small diameter portion 40b, and spherical sealing members (such as steel balls) 72b and 73b are pushed halfway into the gas supply passages <NUM> and <NUM> from the opening side thereof so as to seal the gas supply passages <NUM> and <NUM>, respectively. The communication passage 73a is formed to transect the air supply passage <NUM> so as to communicate with both the air supply passage <NUM> and the air supply passage <NUM>.

The distal end of each of the air supply passages <NUM> to <NUM> is provided with a corresponding nozzle <NUM>, <NUM>, <NUM> with a small diameter. The distal ends of the nozzles <NUM>, <NUM> and <NUM> open to the inner wall surface of the cylindrical housing <NUM> so as to form air supply ports <NUM>, <NUM> and <NUM>, respectively. The nozzles <NUM>, <NUM> and <NUM> are arranged in such a manner that the cutting tool <NUM> disposed inside the cylindrical housing <NUM> receives a rotary force about the rotation axis 41a in the direction indicated by an arrow <NUM> (the clockwise direction in <FIG>) which is generated by the pressurized air ejected from the nozzles <NUM>, <NUM>, and <NUM>.

As illustrated in <FIG>, the exhaust passages <NUM> and <NUM> are formed below the air supply passages <NUM> to <NUM> as through holes extending from the rear end surface 40c to the inner wall surface of the cylindrical housing <NUM>. The distal ends of the exhaust passages <NUM> and <NUM> open to the inner wall surface of the cylindrical housing <NUM> so as to form exhaust ports. The base ends of the exhaust passages <NUM> and <NUM> open to the rear end face 40c, and communicate with an exhaust means (not shown) via the connection member 2a and the supply tube <NUM> illustrated in <FIG>, using the inner cylindrical portion of the grip <NUM> as an exhaust path. Further, an auxiliary exhaust port <NUM> is formed in the shape of an elongated hole in communication with the exhaust passages <NUM> and <NUM>, and thereby, a part of the air introduced into a first air passage <NUM> is directly discharged from the exhaust passages <NUM> and <NUM> without being guided to a second air passage <NUM> and a third air passage <NUM>.

Further, the shaft member <NUM> is provide with a light member <NUM> configured to illuminate the distal end of the cutting tool <NUM> and a chip air passage <NUM> configured to supply water to the distal end of the cutting tool <NUM>. Note that a water supply pipe and an air supply pipe in communication with the chip air passage <NUM> are not shown in the figures.

As illustrated in <FIG> and <FIG>, the cylindrical housing <NUM> of the head <NUM> has an cylindrical inner space <NUM> with a shape and a size corresponding to the outer profile of the driving member <NUM> configured to convert the pressurized air ejected from the air supply passages <NUM> to <NUM> into a rotary force to drive the cutting tool <NUM>. The inner space <NUM> is opened with an upper opening <NUM> and a lower opening <NUM>.

In order to hold the driving member <NUM> at a predefined position in the inner space <NUM>, a ring-shaped sub-housing <NUM> is provided and detachably attached to the upper opening <NUM>. An external thread is formed on an outer circumferential surface of the sub-housing <NUM>, and is screwed into an internal thread formed on an inner circumferential surface of the opening <NUM>, and the engagement is locked by a screw <NUM> screwed into the head <NUM>.

Further, a cap support ring <NUM> is disposed on the upper surface of the sub-housing <NUM>, and a cap <NUM> is detachably attached to the opening <NUM> through the intermediary of the cap support ring <NUM>. The cap support ring <NUM> engages with the circumferential edge of the cap <NUM> so as to prevent the cap <NUM> from falling out from the upper direction while allowing the cap <NUM> to move up and down along the rotation axis 41a.

As illustrated in <FIG>, a spring member <NUM> is resiliently biased between the inner surface of the cap <NUM> and the driving member <NUM>. The cap <NUM> is stably held at a position illustrated in the figure by a biasing force of the spring member <NUM>. In the resiliently biased state, the spring member <NUM> acts on a pressing ring <NUM> which is disposed to straddle an outer ring <NUM> of an upper bearing <NUM> and the cap support ring <NUM>, and functions to hold the driving member <NUM> at a predefined position. When the cap <NUM> is pressed against the biasing force of the spring member <NUM>, the cutting tool <NUM> may be released from a tool support member <NUM> for replacement.

As illustrated in <FIG>, the tool support member <NUM> is provided in the driving member <NUM> of the cutting tool <NUM> so as to support the cutting tool <NUM> along the rotation axis 41a of the inner space <NUM>. The tool support member <NUM> is formed with a hole (tool support hole) <NUM> having a predetermined depth from one end (the lower end in <FIG> and <FIG>). The tool support member <NUM> is provided with a chuck mechanism configured to hold the cutting tool <NUM> inserted into the tool support hole <NUM>.

The tool support member <NUM> is rotatably supported about the rotation axis 41a by an upper bearing <NUM> provided at an upper position and a lower bearing <NUM> provided at a lower position. The upper bearing <NUM> includes an inner ring <NUM>, an outer ring <NUM> arranged concentrically with the inner ring <NUM>, and a plurality of balls <NUM> arranged between the inner ring <NUM> and the outer ring <NUM>. The inner ring <NUM> is fixed outside the tool support member <NUM>. The outer ring <NUM> is pressed into the sub-housing <NUM> and fixed relative to the sub-housing <NUM> via an O-ring <NUM>. The inner circumference of the sub-housing <NUM> is formed with a circumferential groove 413a for housing the O-ring <NUM> therein. The O-ring <NUM> prevents the pressurized air ejected to a rotor <NUM> from leaking upward.

The lower bearing <NUM> is a ball bearing similar to the upper bearing <NUM>. Similar to the upper bearing <NUM>, the lower bearing <NUM> includes an inner ring <NUM>, an outer ring <NUM>, and a plurality of balls <NUM> disposed therebetween. The inner ring <NUM> is fixed outside the tool support member <NUM>. The outer ring <NUM> is pressed into the inner space <NUM> of the cylindrical housing <NUM> and fixed relative to the inner space <NUM> via an O-ring <NUM>. The O-ring <NUM> prevents the pressurized air from leaking downward.

The inner space <NUM> of the cylindrical housing <NUM> is shaped and sized in accordance with the region where the upper bearing <NUM>, the lower bearing <NUM> and the rotor <NUM> are arranged, and is substantially composed of an upper cylindrical portion <NUM> with a large inner diameter, a lower cylindrical portion <NUM> with a small inner diameter, and a step portion <NUM> formed between the upper cylindrical portion <NUM> and the lower cylindrical portion <NUM>. The O-ring <NUM> provided for the lower bearing <NUM> is housed in a circumferential groove 417a formed on the inner circumference of the lower cylindrical portion <NUM>.

A double-wheel rotor <NUM> is integrally provided in the region of the tool support member <NUM> between the upper bearing <NUM> and the lower bearing <NUM> so as to rotate the tool support member <NUM> and the cutting tool <NUM> about the rotation axis 41a via the tool support member <NUM> by using the pressurized air ejected from the air supply passages <NUM> to <NUM>.

The height position of the first air passage <NUM> (the height position along the rotation axis 41a) is set in such a manner that when the rotor <NUM> is provided in the inner space <NUM>, the pressurized air ejected from the nozzles <NUM>, <NUM>, and <NUM> is blown into the upper portion of the first air passage <NUM>. A part of the first air passage <NUM> from the lower surface of the upper ceiling wall to the outer circumference of a large diameter ring portion <NUM> is formed as a curved surface <NUM> curved inward along the radial direction so that the air blown into the first air passage <NUM> from the outside of the rotor <NUM> in the radial direction is smoothly directed downward along the curved surface <NUM> with a minimum air resistance. The side surface of each first turbine blade <NUM> when viewed from the direction toward the rotation axis 41a is recessed from the upstream side toward the downstream side in the rotation direction <NUM> of the rotor.

As illustrated in <FIG>, an air guide member <NUM> configured to guide air from a first turbine blade portion <NUM> to a second turbine blade portion <NUM> is provided on the inner circumference of the inner space <NUM> of the head <NUM>, and specifically on the step portion <NUM>.

The pressurized ejected from the air supply passages <NUM> to <NUM> into the inner space <NUM> is guided into the first air passage <NUM> from the outside thereof in the radial direction, and the pressurized ejected from the lower end of the first air passage <NUM> is guided into the third air passage <NUM> from outside thereof in the radial direction. The air guide member <NUM> includes a plurality (seven in the present example) of second air passages <NUM> configured to guide air from the lower end of the first air passage <NUM> into the third air passage <NUM>. The plurality of second air passages <NUM> are arranged side by side along the circumferential direction about the rotation axis 41a.

When the air turbine handpiece <NUM> with the configuration as described above is used to cut a tooth, a cutting tool <NUM> suitable for a specific operation is selected as illustrated in <FIG>, and is mounted to the tool support member <NUM> from the lower end thereof. Next, the pressurized air is supplied from a pressurized air supply source (not shown) into each of the air supply passages <NUM> to <NUM> through the supply tube <NUM>. The pressurized air is supplied from the air supply passages <NUM> to <NUM> to the corresponding nozzles <NUM>, <NUM> and <NUM>. The pressurized air passing through the nozzles <NUM>, <NUM> and <NUM> is accelerated and ejected from the air supply ports <NUM>, <NUM> and <NUM> in a direction perpendicular to the rotation axis 41a of the rotor <NUM> (downstream side in the rotation direction <NUM> of the rotor <NUM>). When the pressurized air is blown into the first air passage <NUM>, the energy of the pressurized air acts on a working surface <NUM> of the first turbine blade <NUM> in the first turbine blade portion <NUM>, and the rotor <NUM> is rotated around the rotation axis 41a in the direction indicated by the arrow <NUM>. Because of the rotation, the pressurized air is sequentially blown into the first air passage <NUM> running opposite to the air supply ports <NUM>, <NUM> and <NUM> to keep the rotor <NUM> rotating. Since the side surface of the first turbine blade <NUM> is recessed in the rotation direction <NUM>, the energy of the pressurized air blown into the first air passage <NUM> acts on the working surface <NUM>, and is effectively consumed as the rotary power of the rotor <NUM>. Therefore, the rotor <NUM> rotates at a high rotary speed with a large rotary torque.

Thus, in the air turbine handpiece <NUM>, the rotor <NUM> provided inside the head <NUM> is rotated by the pressurized air, and the cutting tool <NUM> is rotated by the rotation of the rotor <NUM>. When an abnormality in which those members which are normally not in contact with each other during the rotation of the rotor <NUM> contact each other occurs, the surface of the head <NUM> may become overheated by the frictional heat generated by the contacting members, whereby the temperature of the surface of the head <NUM> may be raised to approximately <NUM> or more. In order to prevent such abnormality from occurring, the operator needs to determine whether or not a thermal abnormality is present in the air turbine handpiece <NUM>.

Conventionally, as a technical solution, a temperature detecting member that detects the temperature of a handpiece is attached to the handpiece. However, in the conventional detection method, since the temperature detecting member is integrated with the handpiece, the temperature detecting member will suffer from fast degradation during the use of the handpiece. For example, a dental handpiece is subjected to an autoclave sterilization of <NUM> each time after use, but it is hard for a temperature detecting member to withstand the temperature of <NUM> for a long period of time. Therefore, it is required to find an approach so as to determine whether or not a thermal abnormality of a handpiece is present for a long period of time. Thus, a detection tool <NUM> and a detection method are provided that are capable of determining whether or not a thermal abnormality is present in a handpiece for a long period of time. Hereinafter, the detection tool <NUM> and the detection method will be described in detail.

The configuration of the detection tool <NUM> will be described with reference to <FIG> and <FIG>.

<FIG> is a schematic view illustrating one side surface of the detection tool. As illustrated in <FIG>, the detection tool <NUM> is a card-type temperature detection tool including a main body <NUM>. One surface (for example, the front surface) 500a on one side (for example, the front side) of the main body <NUM> includes a region <NUM>, a region <NUM> and a region <NUM>.

The region <NUM> is provided with a detection section <NUM> that detects the temperature of air released from the air turbine handpiece <NUM>.

The detection section <NUM> has a shape serving as a target into which the air released from the air turbine handpiece <NUM> is blown. As illustrated in <FIG>, the cross section of the head <NUM> of the air turbine handpiece <NUM> is circular. Therefore, the detection section <NUM> has a size equal to or greater than the size of the head <NUM> of the air turbine handpiece <NUM> is accommodated, and is formed into the same circular shape as the head <NUM>.

The detection section <NUM> includes a thermo-sensitive material <NUM> which changes color in response to a temperature change. The thermo-sensitive material <NUM> changes color when the thermo-sensitive material <NUM> is heated to a temperature equal to or higher than a predetermined temperature, and once the color of the thermo-sensitive material <NUM> is changed, the thermo-sensitive material <NUM> does not return to an original color.

The temperature at which the thermo-sensitive material <NUM> changes color is set to a temperature at which a thermal abnormality in the air turbine handpiece <NUM> may be appropriately detected without any erroneous detection caused by the indoor temperature. For example, the thermo-sensitive material <NUM> changes color when the thermo-sensitive material <NUM> is heated to about <NUM> or more. When the thermo-sensitive material <NUM> is blown by the air released from the air turbine handpiece <NUM>, the thermo-sensitive material <NUM> maintains color at a predetermined color (for example yellow) when the temperature of the air is lower than a predetermined temperature (for example about <NUM>), and changes from a predetermined color (for example yellow) to a specific color (for example red) when the temperature of the air is equal to or higher than the predetermined temperature (for example about <NUM>).

In general, the room temperature of a dental hospital is set at a comfortable temperature of <NUM>, but it may become higher than <NUM> in summer or the like. In such an environment, if the thermo-sensitive material <NUM> changes color at <NUM>, the thermo-sensitive material <NUM> may change color due to the influence of the indoor temperature. On the other hand, it has been empirically confirmed that the air turbine handpiece <NUM> rises up to about <NUM> or more when a thermal abnormality is present in the air turbine handpiece <NUM>. Therefore, if the thermo-sensitive material <NUM> that changes color when heated to about <NUM> or more is provided in the detection section <NUM>, it is possible for the detection tool <NUM> to further accurately detect the thermal abnormality of the air turbine handpiece <NUM> without any erroneous detection. It is preferable that the thermo-sensitive material <NUM> changes color when heated to <NUM> or more, but it is acceptable that the thermo-sensitive material <NUM> changes color when detecting a temperature in the range of <NUM> to <NUM>±<NUM> or <NUM>±<NUM>.

The thermo-sensitive material <NUM> may be a sticker-type detection member to be stuck to a position corresponding to the detection section <NUM> in the region <NUM>, or may be a paint-type detection member to be painted to a position corresponding to the detection section <NUM> in the region <NUM>.

The region <NUM> is a region for describing the content of color changes of the thermo-sensitive material <NUM>. For example, when the thermo-sensitive material <NUM> is blown by the air released from the head <NUM> of the air turbine handpiece <NUM>, the region <NUM> describes that the use of the air turbine handpiece <NUM> is permitted if the thermo-sensitive material <NUM> maintains its color at a predetermined color (for example yellow), and the use of the air turbine handpiece <NUM> is prohibited if the thermo-sensitive material <NUM> changes its color from a predetermined color (for example yellow) to a specific color (for example red).

The region <NUM> describes a warning which indicates that the use of the air turbine handpiece <NUM> is prohibited if the color of the thermo-sensitive material <NUM> is changed.

<FIG> is a schematic view illustrating the other side surface of the detection tool <NUM>. As illustrated in <FIG>, one surface (for example, the back surface) 500b on the other side (for example, the back side) of the main body <NUM> includes a region <NUM>.

The region <NUM> is a region for describing a detection method for detecting the temperature of air released from the air turbine handpiece <NUM> by using the detection section <NUM>. For example, the region <NUM> describes that the head <NUM> of the air turbine handpiece <NUM> is brought close to the detection section <NUM> within a predetermined distance after the air turbine handpiece <NUM> has been driven to operate for a predetermined time. The predetermined time is <NUM> seconds or more, and preferably <NUM> seconds to <NUM> seconds (for example, <NUM> seconds). The predetermined distance between the detection section <NUM> and the air turbine handpiece <NUM> is <NUM> to <NUM>, and preferably <NUM> to <NUM>.

Although the region <NUM> illustrated in <FIG> describes that the air turbine handpiece <NUM> is driven to operate for <NUM> seconds, it is acceptable to describe that the air turbine handpiece <NUM> is driven to operate for <NUM> seconds or more, or that the air turbine handpiece <NUM> is driven to operate for <NUM> seconds to <NUM> seconds. Although the region <NUM> illustrated in <FIG> describes that the distance between the detection section <NUM> and the air turbine handpiece <NUM> is <NUM> to <NUM>, it is acceptable to describe that the distance between the detection section <NUM> and the air turbine handpiece <NUM> is <NUM> to <NUM>.

A detection method for detecting the temperature of air released from the air turbine handpiece <NUM> by using the detection tool <NUM> will be described with reference to <FIG> is a schematic view illustrating an example usage of the detection tool <NUM>.

As illustrated in <FIG>, firstly, an operator holds the air turbine handpiece <NUM> with one hand, and holds the card-type detection tool <NUM> with the other hand. Then, the operator brings the head <NUM> of the air turbine handpiece <NUM> close to the detection section <NUM> of the air turbine handpiece <NUM> within a predetermined distance after the air turbine handpiece <NUM> has been driven to operate for at least <NUM> seconds, and preferably <NUM> seconds to <NUM> seconds (for example, <NUM> seconds). Specifically, the operator moves the head <NUM> of the air turbine handpiece <NUM> close to the detection section <NUM> until the distance between the detection section <NUM> and the air turbine handpiece <NUM> is <NUM> to <NUM>, and preferably <NUM> to <NUM>.

In the present embodiment, the duration of <NUM> seconds to <NUM> seconds is such a duration that is required to stabilize the operation of the air turbine handpiece <NUM>. Thus, at the time of detecting the temperature of air released from the air turbine handpiece <NUM>, the operator may use the detection tool <NUM> to detect the temperature of the air after the operation of the air turbine handpiece <NUM> is stabilized.

The distance of <NUM> to <NUM> between the detection section <NUM> and the air turbine handpiece <NUM> is such a distance range that allows the thermo-sensitive material <NUM> included in the detection section <NUM> to stably detect the temperature of air released from the air turbine handpiece <NUM>, which makes it possible for the operator to further accurately detect the temperature of air released from the air turbine handpiece <NUM>.

As illustrated in Figs. 8A and 8B, if the temperature of air released from the air turbine handpiece <NUM> is lower than a predetermined temperature (for example, approximately <NUM>), the thermo-sensitive material <NUM> maintains its color at a predetermined color (for example, yellow). In this case, since no thermal abnormality is present in the air turbine handpiece <NUM>, the use of the air turbine handpiece <NUM> is permitted.

On the other hand, as illustrated in Figs. <NUM>(A) and <NUM>(C), if the temperature of air released from the air turbine handpiece <NUM> is equal to or higher than a predetermined temperature (for example, approximately <NUM>), the thermo-sensitive material <NUM> changes its color from a predetermined color (for example, yellow) to a specific color (for example, red). In this case, since a thermal abnormality is present in the air turbine handpiece <NUM>, the use of the air turbine handpiece <NUM> is prohibited.

As described above, the determination of a thermal abnormality in the air turbine handpiece <NUM> by using the detection tool <NUM> is performed before using the air turbine handpiece <NUM> to treat a patient. Thus, an operator such as a dentist may determine the thermal abnormality in the air turbine handpiece <NUM> before treating a patient.

The following concepts have been described above.

The detection tool <NUM> includes a detection section <NUM> that detects the temperature of air released from the air turbine handpiece <NUM>, and a main body <NUM> that includes a surface. The detection section <NUM> is provided on the surface so as to allow the air turbine handpiece <NUM> to be brought close to the detection section <NUM>.

Thus, the operator may determine whether or not a thermal abnormality is present in the air turbine handpiece <NUM> by bringing the air turbine handpiece <NUM> close to the detection section <NUM> of the detection tool <NUM>. Further, since the detection tool <NUM> is separate from the air turbine handpiece <NUM>, it is possible to use the detection tool <NUM> for a long period of time to determine whether or not a thermal abnormality is present in the air turbine handpiece <NUM> without suffering from degradation during the use of the air turbine handpiece <NUM>.

The detection section <NUM> includes a thermo-sensitive material <NUM> which changes in response to a temperature change. For example, the thermo-sensitive material <NUM> may change color from yellow to red in response to a temperature change.

Thus, the operator may determine whether or not a thermal abnormality is present in the air turbine handpiece <NUM> by utilizing the characteristics of the thermo-sensitive material <NUM>.

The thermo-sensitive material <NUM> changes color when it detects air at a temperature equal to or higher than a predetermined temperature. For example, the thermo-sensitive material <NUM> may change color when it detects air at a temperature equal to or higher than about <NUM> (for example a temperature from <NUM> to <NUM>±<NUM> or <NUM>±<NUM>) at which a thermal abnormality in the air turbine handpiece <NUM> may be appropriately detected without any erroneous detection caused by the indoor temperature.

Thus, the operator may further accurately determine whether or not a thermal abnormality is present in the air turbine handpiece <NUM> without being adversely affected by the indoor temperature as much as possible and thereby without any erroneous detection.

The thermo-sensitive material <NUM> is configured not to return to the original color once the color thereof is changed in response to the temperature change.

Since the thermo-sensitive material <NUM> does not return to the original color once the color thereof is changed, it is possible to prevent the operator from missing a thermal abnormality, which makes it possible for the operator to accurately determine whether or not a thermal abnormality is present in the air turbine handpiece <NUM>.

As illustrated in <FIG>, the main body <NUM> includes a region <NUM> for describing the content of color changes of the thermo-sensitive material <NUM>.

Thus, the operator may appropriately use the detection tool <NUM> to determine whether or not a thermal abnormality is present in the air turbine handpiece <NUM> by checking the content described in the region <NUM> included in the main body <NUM>.

The detection section <NUM> has a shape into which the air released from the air turbine handpiece <NUM> is blown.

Thus, the operator may appropriately blow the air released from the air turbine handpiece <NUM> to the detection section <NUM> so as to accurately determine whether or not a thermal abnormality is present in the air turbine handpiece <NUM>.

The detection section <NUM> has a size equal to or greater than that of the head <NUM> of the air turbine handpiece <NUM>.

Thus, the operator may appropriately bring the head <NUM> of the air turbine handpiece <NUM> close to the detection section <NUM> so as to accurately determine whether or not a thermal abnormality is present in the air turbine handpiece <NUM>.

The main body <NUM> includes a region <NUM> for describing a detection method for detecting the temperature of air released from the air turbine handpiece <NUM> by using the detection section <NUM>, and the detection method includes bringing the air turbine handpiece <NUM> close to the detection section <NUM> within a predetermined distance after the air turbine handpiece <NUM> has been driven to operate for a predetermined time.

Thus, the operator may accurately determine whether or not a thermal abnormality is present in the air turbine handpiece <NUM> by using the method.

The detection method includes bringing the head <NUM> of the air turbine handpiece <NUM> close to the detection section <NUM> within a predetermined distance.

Thus, the operator may further accurately detect the temperature of air released from the air turbine handpiece <NUM> by the detection section <NUM> so as to further accurately determine whether or not a thermal abnormality is present in the air turbine handpiece <NUM>.

The predetermined time for driving the air turbine handpiece <NUM> before the air turbine handpiece <NUM> is brought close to the detection section <NUM> of the detection tool <NUM> is <NUM> seconds or more, and preferably <NUM> seconds to <NUM> seconds (for example, <NUM> seconds).

Thus, the operator may use the detection tool <NUM> to detect the temperature of the air after the operation of the air turbine handpiece <NUM> is stabilized.

The predetermined distance between the detection section <NUM> and the air turbine handpiece <NUM> is <NUM> to <NUM>, and preferably <NUM> to <NUM>.

Thus, the operator may further accurately detect the temperature of air released from the air turbine handpiece <NUM>.

The present disclosure is not limited by the above description, and various modifications and applications are possible. Hereinafter, applicable modifications of the present disclosure will be described.

Although the detection tool <NUM> described above is configured to detect the temperature of air released from the air turbine handpiece <NUM> by using the color changes of the thermo-sensitive material <NUM>, the present disclosure is not limited thereto.

<FIG> is a schematic diagram illustrating another kind of detection tool <NUM>. The detection tool <NUM> illustrated in <FIG> is a card-type detection tool that electrically measures the temperature. Specifically, one surface (for example, the front surface) on one side (for example, the front side) of the main body <NUM> of the detection tool <NUM> is provided with a detection section <NUM> that detects the temperature of air released from the air turbine handpiece <NUM> and a display unit <NUM> that displays the temperature of the air detected by the detection section <NUM>.

The detection section <NUM> is a temperature sensor for electrically measuring a temperature, such as a built-in thermocouple or a built-in temperature measuring resistor. When an operator brings the head <NUM> of the air turbine handpiece <NUM> close to the detection section <NUM>, the detection section <NUM> electrically measures the temperature of air released from the head <NUM>. The measured air temperature is displayed on the display unit <NUM>.

As described above, the detection tool <NUM> includes a detection section <NUM> that detects the temperature of air released from the air turbine handpiece <NUM>, and a main body <NUM> that includes a surface. The detection section <NUM> is provided on the surface so as to allow the air turbine handpiece <NUM> to be brought close to the detection section <NUM>.

The detection tool is not limited to the detection tool <NUM> and the detection tool <NUM>, and any other temperature measuring device such as a thermometer or a temperature sensor may be used to measure the temperature of air released from the air turbine handpiece <NUM>.

The detection tool may be a contact-type detection tool that measures the temperature of air released from the air turbine handpiece <NUM> by contacting the air turbine handpiece <NUM>, or a non-contact type detection tool that measures the temperature of air released from the air turbine handpiece <NUM> without contacting the air turbine handpiece <NUM>.

The thermo-sensitive material <NUM> may be an irreversible thermo-sensitive material that does not return to the original color after it is heated to a temperature equal to or higher than a preset temperature to change color, but it is not limited thereto. For example, the thermo-sensitive material may be a reversible thermo-sensitive material which changes color after it is heated to a temperature equal to or higher than a preset temperature, and then returns to the original color when it is cooled to a temperature lower than the preset temperature. Thus, the detection tool using the reversible thermo-sensitive material may be repeatedly used by the operator a plurality of times, which is different from the disposable detection tool <NUM> using the irreversible thermo-sensitive material.

The thermo-sensitive material <NUM> may change color when it is heated to a temperature equal to or higher than a preset temperature, but it is not limited to the color, and it is acceptable to change the pattern or shape thereof.

Although the detection section <NUM> may be formed into a circular shape in accordance with the cross section of the head <NUM> of the air turbine handpiece <NUM>, the detection section <NUM> may be formed in another shape such as a quadrangular shape as long as the size of the detection section <NUM> is equal to or greater than that of the head <NUM> of the air turbine handpiece <NUM>.

Although the detection tool <NUM> may be configured to detect the temperature of air released from the air turbine handpiece <NUM> which has the configuration as illustrated in <FIG>, the detection tool <NUM> may detect the temperature of air released from an air turbine handpiece that has another configuration. In other words, the detection tool <NUM> may be used in combination with any air turbine handpiece that generates air.

Claim 1:
A detection method for detecting a temperature of air, the detection method comprising:
driving an air turbine handpiece (<NUM>) to operate for a predetermined time; and
bringing the air turbine handpiece (<NUM>) close to a detection tool (<NUM>) that detects the temperature of air within a predetermined distance,
wherein the air turbine handpiece (<NUM>) comprises a head (<NUM>) and a cutting tool (<NUM>) attached to the head (<NUM>),
the air turbine handpiece (<NUM>) is configured to rotate the cutting tool (<NUM>) by a driving force generated by air,
the detection tool (<NUM>) including a thermo-sensitive material (<NUM>) which changes color in response to a temperature change,
wherein the thermo-sensitive material (<NUM>) changes color when detecting an air higher than <NUM>.