JP3043054B2 - Hand piece - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial applications]

The present invention relates to a handpiece used for dental treatment or the like.

[Prior art]

Conventionally, handpieces of various structures have been proposed, and FIG. 4 shows an example of such a handpiece, in which a head portion 2 can be detachably detached from a grip portion 1. The internal structure of the head head 3 is as shown in FIG. 5, for example, a hollow rotary shaft 4 is installed at the center thereof, and an impeller 5 is mounted on the outer periphery of the rotary shaft 4. A chuck 7 for holding the tool 6 is built in, and the whole is accommodated in a head casing 8, and bearings (bearing mechanisms) 9 are provided at two places (up and down) between the casing 8 and the outer periphery of the rotating shaft 4. , 9 are installed, and the injection of compressed air or the like to the impeller 5 causes the rotating shaft 4 to rotate at high speed and the tool 6 to rotate.

[Problems to be solved by the invention]

However, in the conventional head 3 described above, since the constituent members of each part are generally made of metal, there are the following problems to be improved. (1). First, in the case of a metal material, integral molding such as molding is not suitable, and in general, individual products must be manufactured by machining. For this reason, the cost of individual components increases, and the number of components is large. As a result, an increase in manufacturing cost is unavoidable as a whole, and it has been difficult to reduce costs. (2). Even more important recently, infections through handpieces have become a serious problem. In other words, in the case of dental treatment, the handpiece is placed in the mouth of the patient, so the problem of recent infectious diseases (such as AIDS and hepatitis A) will cause the handpiece to be used for the next patient. Need to be sterilized. For this sterilization, for example, an autoclave method using high-temperature and high-pressure steam, a chemiclave method using a chemical such as alcohol, or an ultraviolet irradiation method using ultraviolet rays have been proposed.However, in the autoclave method and the chemiclave method, heating and cooling are performed. , Drying and other steps are required, which requires a long time (about 40 minutes to 1 hour), and also requires a dedicated liquid. On the other hand, although the ultraviolet irradiation method has an advantage that it can be completed in a short time (about several tens of seconds), it has a disadvantage that sterilization of a portion where the light beam does not turn or the inside tends to be incomplete. The present invention has been made in view of such a conventional situation.

[Means for Solving the Problems]

That is, in order to solve the above-mentioned conventional problems, at least the rotating shaft and the impeller housed in the head casing are integrally formed of plastic, and the head casing is also formed of an inorganic material such as plastic or ceramic. Then, an annular convex portion for sealing is provided by integral molding on a portion of the head casing that comes into contact with the bearing exterior portion of the rotating shaft, and a bearing interior portion is provided on the outer periphery of the rotating shaft, or on the outer periphery of the rotating shaft, The bearing interior part of the rotary shaft is directly provided.

According to the present invention, the manufacturing cost can be reduced by the above configuration, but sterilization can be performed in a very short time due to non-metallization. High-frequency sterilization using microwaves can be used.

【Example】

FIG. 1 shows an embodiment of a handpiece according to the present invention. In the head head 13 of this handpiece, a head casing 18 is divided into two parts, and a hollow rotary shaft 14, a peripheral impeller 15 and a stopper 17 for a chuck 17 are provided at the center in the longitudinal direction of each of the casing parts 18 a and 18 b. The portion 17a is integrally formed. In the hollow of the rotating shaft 14, for holding a tool,
A spring material 17b for chuck is housed, and the spring material 17b is fixed by the stopper portion 17a and a cylindrical stopper 17c inserted from the tool insertion port side. Two locations on the outer periphery of the integrally formed rotary shaft 14 (in the figure,
Bearings (bearing mechanisms) 19, 19 are provided between the upper and lower portions) and the inside of each of the casing portions 18a, 18b. The bearings 19, 19 are composed of a ball 19a, and an annular interior part (inner ring) 19b and an exterior part (outer ring) 19c that support the ball 19a inside and outside.
The annular projections 18c, 18c for sealing are provided on the portions of the 18a, 18b that come into contact with the exterior portion 19c. Each part (constituent element) of the head head 3 thus formed is made of all plastics (including not only ordinary resins but also hard rubbers), preferably hard plastics, engineering plastics, and even ceramics. Of inorganic materials. Therefore, the above-described rotary shaft 14, impeller 15, and chuck
In addition to integral molding with the 17 stopper part 17a,
Each of the casing portions 18a, 18b and the annular projections 18c, 18c for sealing are also integrally formed. As a result, the manufacture of each part is facilitated and the number of parts is reduced, so that the cost can be significantly reduced. Furthermore, the use of all-metallization makes it possible to use a high-frequency sterilization method using microwaves, thereby achieving sterilization in a very short time (about 20 to 30 seconds). 2 and 3 show other embodiments of the handpiece according to the present invention. These handpieces are also basically the same as those shown in FIG. 1, but by integrally forming the rotating shaft 14 and the impeller 15, the interior part 19 b of the bearing 19 is directly attached to the outer periphery of the rotating shaft 14. It is provided. In the handpiece shown in FIG. 2, a ball 19a is used for the bearing 19, and in the handpiece shown in FIG. 3, a columnar roller 19a 'is used instead of the ball 19a. In any case, this further reduces the number of components. In the present invention, the structure of the chuck 17, the two-part structure of the head casing 18, the structure of the bearing 19, and the like are not limited to those in the above embodiments. Also, in each of the above embodiments, each part is made of an inorganic material such as plastic or ceramic, in order to enable high-frequency sterilization using microwaves. For the purpose, for each part other than the rotating shaft and the impeller,
Various combinations are conceivable, such as a metal as in the past, or an inorganic material such as plastic or ceramic.

【The invention's effect】

As apparent from the above description, according to the present invention, the following excellent effects can be obtained. (1). First, at least the rotating shaft and the impeller housed in the head casing are integrally formed of plastic, and the head casing is also formed of an inorganic material such as plastic or ceramic. The sealing annular convex portion is provided by integral molding at the contacting portion, and the bearing interior portion is provided on the outer periphery of the rotating shaft, or the bearing interior portion of the rotating shaft is directly provided on the outer periphery of the rotating shaft. Therefore, it is excellent in mass productivity and cost can be reduced. This non-metallization also enables the use of microwave-based high-frequency sterilization, which enables sterilization in a very short time. (2). In other words, when the head casing is integrally formed of an inorganic material such as plastic or ceramic, a necessary portion, particularly, an annular convex portion for sealing, which is in contact with an outer portion of the bearing, can be easily integrally formed. Further, the O-ring storage groove is not required, so that the mass productivity is also excellent and the cost can be reduced. Needless to say, the parts for accommodating the respective parts of the casing (the rotating shaft, the impeller, the bearings, etc.) can be integrally formed without machining, so that a design with extremely high flexibility is possible. (3). In particular, the fact that the high-frequency sterilization method using microwaves can be used as described above is a very significant advantage. As described above, the high-frequency sterilization method is completed in about 20 to 30 seconds, and steps such as heating, cooling, and drying (required time, about 40
Minutes to about one hour) is not required. Therefore, conventionally, since a single sterilization takes a long time, even a small-scale dental clinic or the like requires a large number of fairly expensive handpieces. With the provision of the non-metallized handpiece of the present invention, if several handpieces are provided, it is possible to sufficiently cope with the handpieces, so that thorough sterilization can be expected. Due to this, infectious diseases (AIDS, hepatitis A, etc.), which have become a problem these days,
The problem described above can be solved smoothly. (4). In addition, even if it is partially non-metallized, the following advantages are obtained as secondary effects: lightness, reduction of noise such as metal noise during rotation, vibration reduction, and no maintenance such as lubrication. Can be

[Brief description of the drawings]

1 to 3 are longitudinal cross-sectional views of essential parts showing respective embodiments of a handpiece according to the present invention, FIG. 4 is an exploded side view showing the entire handpiece, and FIG. 5 is a conventional handpiece. It is a longitudinal section of an important section showing a piece. In the figure, 13: head head, 14: rotating shaft, 15: impeller, 17: chuck, 18: head casing, 18c: annular convex part for sealing, 19: bearing, 19a ... ... Ball, 19a '... Columnar roller, 19b ... Inner part (inner ring), 19c ... Outer part (outer ring),

Claims (2)

(57) [Claims] 1. A hand which is housed in a head casing and has a chuck in the hollow of a hollow rotary shaft having an impeller mounted on its outer periphery, and a tool is detachably mounted on the chuck. A piece, at least the rotating shaft and the impeller housed in the head casing are integrally formed of plastic,
The head casing is also formed of an inorganic material such as plastic or ceramic, and a sealing annular convex portion is provided by integral molding on a portion of the head casing that abuts on a bearing exterior part of the rotating shaft, and an outer periphery of the rotating shaft is provided. A handpiece characterized by having a bearing interior part provided in the handpiece. 2. A hand which is housed in a head casing and has a chuck in the hollow of a hollow rotary shaft having an impeller mounted on its outer periphery, and a tool is detachably mounted on the chuck. A piece, at least the rotating shaft and the impeller housed in the head casing are integrally formed of plastic,
The head casing is also formed of an inorganic material such as plastic or ceramic, and a sealing annular convex portion is provided by integral molding on a portion of the head casing that abuts on a bearing exterior part of the rotating shaft, and an outer periphery of the rotating shaft is provided. Wherein the bearing interior part of the rotary shaft is directly provided.