JPH06181934A - Hand piece dental therapy - Google Patents

Abstract

PURPOSE:To use a disposable head section, prevent secondary infection, and reduce the cost of a hand piece by removably fitting the head section to a hand piece main body, forming a turbine chamber between bearings provided in the storage chamber of the head section, and providing an impeller to form an air turbine. CONSTITUTION:A head section (b) is removably fitted to a hand piece main body (a), an air turbine (c) stored in the head section (b) is provided with a lower bearing 6, a rotary shaft 7, an impeller 8, and an upper bearing 9 in a storage chamber 3, and a rod-like cutting tool (d) is provided at the lower end of the rotary shaft 7. When the tip of the hand piece main body (a) is thrust into the tube section 4 of the head section (b), lugs 4 are elastically coupled with a recessed groove a12, and the hand piece main body (a) is fitted in one touch. The impeller 8 and the rotary shaft 7 are rotated by the compressed air flowing from an intake passage 1a in the hand piece main body (a) into the air turbine chamber (c) and flowing to a discharge passage 1b. The head section (b) has a simple structure, secondary machining is rarely required, and it is disposable.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dental treatment handpiece used for removing and cutting a tooth affected area.

[0002]

2. Description of the Related Art Heretofore, a handpiece of this kind has integrally formed a cylindrical main body having a head portion at its tip, has an air turbine built in the head portion, and is provided with a cooling water spray port. A cutting blade is inserted into the cylindrical rotary shaft of the air turbine via a collet, and the air turbine is driven by compressed air flowing through the supply / exhaust passages in the main body of the handpiece. It rotates at high speed to remove and cut the affected part of the tooth.

[0003]

By the way, the biggest problem in the field of dental treatment in recent years is prevention of secondary infections such as AIDS and hepatitis, and it is assumed that the risk of becoming an infection medium at the treatment site is the highest. There is a conventional handpiece having the above-mentioned configuration.

That is, high temperature sterilization by boiling is the most effective and inexpensive for preventing the above-mentioned viral infectious diseases, but in the conventional handpiece, the air turbine built in the head portion is boiled. It is not formed to withstand high temperature sterilization by.

In order to solve this problem, it is conceivable to improve the high temperature durability of the air turbine or to use a sterilization method with a sterilizing gas. However, when these means are adopted, the manufacturing cost of the handpiece or The cost for sterilization increases, which may lead to a high treatment cost and a large increase in patient burden.

The present invention has been made in view of the above conventional circumstances, and an object of the present invention is to construct a handpiece main body and a tip head portion so that they can be separated from each other, and to make the head portion extremely low in cost. Sterilization on the main body side uses the boiling method that is the most effective and cheaper for infection prevention, and the head side is disposable for each treatment, and the manufacturing cost and sterilization of the entire handpiece are possible. It is an object of the present invention to provide a dental treatment handpiece that has an excellent effect of preventing infectious diseases while maintaining the cost for the same as the conventional one.

[0007]

In order to achieve the above-mentioned object, a dental treatment handpiece according to the present invention has a handpiece main body and a head portion which are separately formed, and a head is connected via desired connecting means. Part is detachably attached to the body of the handpiece, and the upper and lower bearings are installed inside the accommodating chamber provided in the head part to form a turbine chamber between the two bearings. An air turbine is formed by loading a rotary shaft whose lower end is axially supported and an impeller integrally provided on the outer periphery of the rotary shaft, and a cutting tool is integrally formed continuously with the rotary shaft. Is characterized by.

For the reasons described below, the above bearings are
An inner ring portion formed of an arc-shaped ball sliding contact surface formed on the peripheral surface of the rotating shaft, and an outer ring portion having an arc-shaped ball sliding contact surface that is mounted on the bottom of the housing chamber or the back surface of the lid member and faces the inner ring portion, It is effective to form a plurality of balls slidably mounted between the inner ring portion and the outer ring portion.

Further, it is possible to form a collar portion at the lower end of the impeller and form a compressed air discharge passage at the peripheral edge of the bottom portion of the turbine chamber.

[0010]

According to the above construction, the head portion formed separately from the handpiece main body is mounted on the tip of the handpiece main body through the desired connecting means, and then the air supply passage to the exhaust passage through the accommodation chamber. The compressed air that flows with this drives the impeller inside the turbine room to rotate, and the dental knife is treated by the high speed rotation of the cutting blade. After the treatment is completed, the head part is removed from the main body of the handpiece by releasing the connecting means, the head part is discarded, and the handpiece main body is sterilized by boiling at a high temperature. Attach to the body of the handpiece to treat the next patient.

Further, the air turbine incorporated in the head portion is a simple one comprising upper and lower bearings, a rotary shaft, and an impeller,
Moreover, the cutting tool that is rotated by the drive of the air turbine is also integrated with the rotary shaft without using a holding tool such as a collet, so that the entire head portion can be provided at extremely low cost. Further, from the structure of the second aspect, the upper and lower bearings have an extremely simple structure, and the entire head portion can be provided at a lower cost.

Further, there is a possibility that grease may leak in the lower bearing as a part of the compressed air flowing into the accommodating chamber is discharged from the cutting blade insertion portion of the bottom wall of the head portion. As described above, by providing the collar portion at the lower end of the impeller, a part of the compressed air is prevented from wrapping around to the bottom wall of the head portion, and the compressed air is discharged from the discharge passage provided at the peripheral edge of the bottom of the turbine chamber. To eliminate the grease leak.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the dental treatment handpiece according to the present invention will be described below with reference to FIGS. The handpieces of the present invention each have a handpiece body a formed separately.
In this embodiment, an elastic engaging means is used as a connecting means for detachably mounting the head portion b on the handpiece body a.

The connecting means of the head portion b to the handpiece body a is not limited to this, and for example, although not shown, a screw portion is formed on the outer periphery of the handpiece body a and the head portion b side is provided with this. It is possible to make changes within a known range, such as equipping a nut member that is screwed.

The handpiece body a is a pencil type with a hollow inside by screwing and connecting a cylindrical front case a1 and a rear case a2 made of a metal material having desired durability so that it can be used for a long period of time. It is formed, and its both end openings are covered with lids a3 and a3, respectively.

Inside the handpiece body a, pressure-resistant and heat-resistant pipes for compressed air supply passage 1a and exhaust passage 1b, cooling water passage 1c, and cooling water spraying air passage 1d are provided. The channels 1a to 1d are formed by inserting. Each of the channels 1a to 1d
Each of the forming pipes has a tip and a rear end inserted through the lid a3, and a tip end is connected to the head b and a rear end is connected to a supply source of compressed air or cooling water.

The tip portion of the handpiece body a, that is, the outer periphery of the end portion a1 'of the front case a1 is formed in a substantially drum shape in cross section as shown in FIG. 3, and the outer peripheral surface extends along the longitudinal direction of the case a1. A key groove a11 and an annular groove a12 extending in the circumferential direction of the case a1 are respectively provided as recesses.

The head part b has an air turbine c built in the casing 5. The casing 5 is provided with the housing chamber 3 inside the front end thereof, and is provided on the rear end side thereof with the tubular portion 4 which is externally fitted to the front end of the handpiece body a, and is integrally molded of synthetic resin or a metal material. An air turbine c is accommodated in the accommodation chamber 3 in a accommodation manner.

The tubular portion 4 has the front case a1 on its inner periphery.
The inner circumference is formed in a substantially drum shape in cross section as shown in FIG. In addition, a positioning key 4a, which is inserted into the key groove a11 and serves as a guide when the end portion a1 'is fitted, is formed on its inner peripheral surface so as to project along the axial direction of the tubular portion 4.

On the inner circumference of the rear end opening portion of the cylindrical portion 4, there are provided a plurality of retaining projections 4b (three in the drawing) which are elastically engaged with the concave groove a12 in a detachable manner. The protrusions 4b and the concave groove a12 are elastically engaged and disengaged in the direction, so that the head portion b can be detachably attached to the tip of the handpiece body a. The key 4a and each protrusion
4b is integrally formed when forming the tubular portion 4.

The outer periphery of the end portion a1 'of the front case a1 is formed in a taper shape from the rear end to the front end, and
The inner circumference of the cylindrical portion 4 is formed in an expanded shape from the inner end toward the rear end opening. As a result, the front case end portion a1 'can be fitted into the tubular portion 4 without being obstructed by the protrusions 4b, and the protrusions 4b can be prevented.
The engagement between 4b and the concave groove a12 can be performed without any trouble.

An air supply passage 41 and an exhaust passage 42 for communicating the air supply passage 1a and the exhaust passage 1b with the turbine chamber c'are opened in the intermediate portion 5a connecting the housing chamber 3 and the tubular portion 4 to each other.

Further, a cooling water spray port 51 is opened in the intermediate portion 5a, and a passage 52 for connecting the cooling water flow path 1c and the air flow path 1d to the spray port 51 is provided.

The accommodating chamber 3 is formed in a bottomed cylindrical shape having an opening 3a on the upper surface, and the insertion hole 3b for the cutting tool is formed in the center of the bottom wall.
To open.

Since the cooling water spray port 51 communicates with both the flow paths 1c and 1d, it is formed by a secondary process such as a drill after the casing 5 is molded. That is, the key 4a, the protrusion 4b, the passages 41, 42, 52, the opening 3
The a, the through holes 3b and the like are formed at the same time when the casing 5 is molded. In short, if the cooling water spray port 51 is provided after molding the casing 5, the casing 5 is completed.

At the inner end of the tubular portion 4, two packings e, front and rear,
Load e. Each packing e has a through hole e1 communicating with the air supply passage 41, a through hole e2 communicating with the exhaust passage 42, and a notch e3 communicating with the passage 52.

In the air turbine c, as shown in an enlarged view in FIG. 1, a lower bearing 6, a rotating shaft 7 and an impeller 8, and an upper bearing 9 are sequentially loaded into the accommodation chamber 3 and the accommodation chamber 3 The lid member 10 is fitted and adhered to the upper surface opening 3a of the to be assembled.

The rotary shaft 7 is made of a desired synthetic resin or metal material, and the impeller 8 is fitted and mounted on the outer periphery thereof to be integrated with the impeller 8. The lower end portion of the rotary shaft 7 is the lower bearing 6
The upper end of the bearing 9 is supported by the upper bearing 9 and is supported in the accommodation chamber 3 at high speed.

A rod-shaped cutting tool d is integrally formed on the lower end of the rotary shaft 7 in a continuous manner. The cutting tool d is inserted into an insertion hole 3b formed in the bottom wall of the accommodation chamber 3 and protrudes from the casing 5.

The lower bearing 6 has an outer ring portion which is fitted in the inner bottom portion 31 of the accommodation chamber 3 whose lower end peripheral edge is formed into a spherical shape.
61, an inner ring portion 62 formed of a spherical ball sliding surface formed on the lower end peripheral surface of the rotating shaft 7, and a plurality of balls (steel balls) slidably mounted between the outer ring portion and the inner ring portion. ) 63, 63 ...
Composed of. A spherical ball sliding contact surface 61a is formed on the inner peripheral surface of the outer ring portion 61 facing the inner ring portion 62.

Further, the outer peripheral surface 61b of the outer ring portion 61 and the inner bottom portion 31 of the housing chamber 3 in sliding contact with the outer peripheral portion 61 are centered on a point h1 where the centers of the balls 63, 63 and the center line g of the rotary shaft 7 intersect. It is formed into a spherical shape to be drawn.

The upper bearing 9 has a recess 10a recessed in the back surface of the lid member 10 having a spherical upper end peripherally fitted with an outer ring portion 91 in the recess 10a, and also has an upper end peripheral surface of the rotary shaft 7. The inner ring portion 92 is formed by providing a spherical ball sliding contact surface on the inner surface, and a plurality of balls (steel balls) 93, 93 ... Are slidably loaded between the outer ring portion 91 and the inner ring portion 92. To be done. Outer ring
A spherical ball-sliding surface 91a having a spherical shape is formed on the inner peripheral surface of the inner surface of the inner surface of the inner surface of the inner surface of the inner ring portion 91 which faces the inner ring portion 92.

The outer peripheral surface 91b of the outer ring portion 91 and the inner bottom portion 10b of the lid member 10 slidingly contacting the outer peripheral portion 91 are centered on a point h2 where the centers of the balls 93, 93 and the center line g of the rotary shaft 7 intersect. It is formed into a spherical shape to be drawn.

In this way, the outer peripheral surfaces 61b, 91 of the respective outer ring portions are
By making b and its sliding contact surface (31, 10b) spherical as described above, when the head part b is assembled, the respective bearings 6, 9 rotate about points h1, h2 and rotate. An automatic centering effect of automatically centering the center of the moving shaft 7 can be obtained.

When loading balls 63 and 93, each ball
63, 93 or the respective ball sliding contact surfaces (61a, 62, 91a,
Apply grease to 92) and use its adhesiveness to make balls
Make sure to prevent the 63 and 93 from falling off. Grease is used as it is as a lubricant.

An air supply passage is provided between the upper and lower bearings 6 and 9.
A turbine chamber c ′ communicating with the air supply passage 1a and the exhaust passage 1b via 41 and the exhaust passage 42 is formed, and the impeller 8 is housed in the turbine chamber c ′.

The impeller 8 is an integrally molded product in which a large number of blades 8a, 8a ... Are connected in series and a disc-shaped brim portion 8b is provided at the lower end portion thereof, which is formed between adjacent blades 8a, 8a. The lower surface side of the gap is closed by the collar portion 8b.

A plurality of compressed air discharge passages f are formed in parallel at the bottom peripheral edge of the turbine chamber c ', that is, at the inner peripheral portion of the bottom of the accommodating chamber 3 facing the outer periphery of the lower bearing 6. Each discharge path f
As shown in FIG. 2, the upper end inlet f1 is formed on the inner wall of the accommodation chamber 3, and the lower end outlet f2 is formed on the inner wall of the cutting blade insertion hole 3b.

In the handpiece of the present embodiment having the above-mentioned structure, the key 4a to be inserted into the key groove a11 is used as a guide, and the tip of the handpiece main body a (the end a of the front case a1).
1 ') is pushed into the cylindrical portion 4 of the head portion b, the respective protrusions 4b
Elastically engages with the concave groove a12, whereby the head portion b is attached to the tip of the handpiece body a with one touch.

At this time, the elastic force of each packing e cushions the collision between the tip of the handpiece main body a and the inner end of the tubular portion 4, and urges the handpiece main body a and the head portion b in the directions of separating from each other. Then, the elastic engagement between the protrusion 4b and the concave groove a12 is made more reliable.

In this state, the air supply passage 1a and the exhaust passage 1b in the handpiece body a are in the turbine chamber c ', the cooling water passage 1c,
The air flow paths 1d communicate with the cooling water spray ports 51, respectively. Then, the impeller 8 and the rotary shaft 7 are driven by the compressed air flowing from the air supply passage 1a into the turbine chamber c'and flowing into the exhaust passage 1b.
When the tool rotates at a high speed, the cutting tool d integrally molded with the rotating shaft 7 rotates at a high speed, thereby removing the tooth affected area.
Make a cut.

At the same time, the cooling water supplied from the cooling water flow path 1c and the spraying air supplied from the air flow path 1d are sprayed from the spray port 51 to cool the affected area.

When a part of the compressed air flowing into the turbine chamber c is discharged from the cutting tool insertion hole 3b, there is a risk that grease leakage in the lower bearing 6 will occur with it. By providing the collar portion 8b at the lower end of the impeller 8 as described above, it is possible to prevent a part of the compressed air from wrapping around in the insertion hole 3b direction, and to discharge the compressed air from each discharge passage f, f. Eliminate grease leakage.

Lower end discharge ports of the respective discharge paths f, f ...
The compressed air discharged from f2 functions as an air bearing that supports the cutting blade d at high speed.

Although a flange is not provided on the upper edge side of the impeller 8, the upper surface of the housing chamber 3 is sealed by the lid member 10, so there is no risk of grease leakage in the upper bearing 9.

After completion of the treatment, if the handpiece body a and the head portion b are pulled in opposite directions, the elastic engagement between the protrusion 4b and the concave groove a12 is released, and the head portion b can be removed with one touch. .

The used head part b removed is discarded,
After sterilizing the handpiece body a by boiling at a high temperature, a new unused head part b is removed as described above.
Attach to the tip and treat the next patient. Therefore, an excellent effect of preventing virus infection using the handpiece as a medium can be obtained.

The head portion b is, as described above, the casing 5, the bearing 6, the rotary shaft 7, the cutting tool d, the impeller 8, the bearing 9,
The head portion b has a very simple structure including the lid member 10, and since each of the constituent members can be formed by press molding or die molding which requires almost no secondary processing by having the structure as described above. Can be provided at an extremely low cost. Therefore, even if the head part b is used disposable for each treatment, the manufacturing cost of the entire handpiece can be maintained at the same level as the conventional one.

In the handpiece of this embodiment,
Each component of the connecting means of the head part b (key groove a11, concave groove
Since the a12, the key 4a, and the protrusion 4b) are covered by the tubular portion 4 of the casing 5, the head portion b is attached to the gripping portion during treatment.
There is no risk that a component for mounting, for example, a collar or the like that is screwed onto the outer periphery of the tubular portion 4 will protrude and the operability of the handpiece during treatment will be reduced.

Further, when the tip of the handpiece is formed into a bent shape as shown in order to improve the operability, there is no fear that the operation allowance of the parts such as the collar described above cannot be secured. Has the effect of.

Further, in this embodiment, the groove a12 and the key groove a11 are provided on the side of the handpiece body a, and the key groove is provided on the side of the head portion b.
4a and the retaining projection 4b are provided, the present invention is not limited to this, and the retaining projection 4b is provided on the handpiece body a side and the concave groove a12 is provided on the head part b side, or It is possible to provide the key 4a on the side of the handpiece body a and the key groove a11 on the side of the head portion b.

Similarly, the concave groove a12 may be composed of a plurality of concave portions that match the protrusion 4b, or the protrusion 4b may be formed in an annular shape that matches the concave groove a12. The head portion b is appropriately selected depending on the convenience of molding.

[0053]

Since the dental treatment handpiece according to the present invention is constructed as described above, it has the following effects.

By attaching the head part with the built-in air turbine to the main body of the handpiece in a detachable manner, the head part which is not durable against high temperature sterilization by boiling is a disposable item which is replaced after each treatment. Since only the main body of the handpiece that can withstand sterilization is repeatedly used, the sterilized state of the entire handpiece can be maintained, and the risk of secondary infection such as AIDS and hepatitis associated with dental treatment can be reliably prevented. Moreover, the sterilization method uses boiling, which is the most effective and cheapest method for preventing infection, and prevents a steep increase in treatment costs and a corresponding increase in patient burden.

Further, by making the casing of the head portion and the entire structure of the air turbine and the respective constituent members to have an extremely simple shape and structure, the whole head portion can be provided at an extremely low cost, and the hand portion can be disposable. The cost of the whole piece will be prevented from increasing and the effect of preventing secondary infections such as AIDS and hepatitis mentioned above will be made more effective.

[Brief description of drawings]

FIG. 1 is a vertical sectional side view showing an embodiment of a dental treatment handpiece according to the present invention, in which only a head portion is separately enlarged.

FIG. 2 is an enlarged cross-sectional view taken along the line (X)-(X) of FIG.

FIG. 3 is an enlarged cross-sectional view taken along the line (Y)-(Y) of FIG.

FIG. 4 is an exploded perspective view showing a head portion.

[Explanation of symbols]

a: Handpiece body 1a: Air supply flow path 1b: Exhaust flow path b: Head part 3: Storage chamber c: Air turbine 6, 9: Bearing 61, 91: Outer ring part 62, 9
2: Inner ring 63, 93: Ball 7: Rotating shaft 8: Impeller 8a: Feather 8b: Collar c ':
Turbine chamber d: Cutting tool f: Discharge path

Claims (3)

[Claims] 1. An air turbine driven by compressed air from the air supply passage is built in a tip head portion of a handpiece body having an air supply passage and an exhaust air passage for compressed air therein. A dental treatment handpiece equipped with a cutting tool that rotates at high speed by driving, wherein the handpiece body and the head portion are separately formed, and the head portion is detachably attached to the handpiece body through a desired connecting means. The upper and lower bearings are installed in the accommodating chamber provided in the head portion to form a turbine chamber between the bearings, and the upper and lower ends are rotatably supported by the bearings in the turbine chamber. A dental treatment hand characterized in that an air turbine is formed by loading a shaft and an impeller integrally provided on the outer periphery of the rotary shaft, and a cutting tool is continuously formed integrally with the rotary shaft. piece. 2. Each of the bearings has an inner ring portion formed of an arc-shaped ball sliding contact surface formed on the peripheral surface of the rotating shaft, and an arc-shaped member that is mounted on the bottom of the housing chamber or the back surface of the lid member and faces the inner ring portion. The handpiece for dental treatment according to claim 1, wherein the handpiece is formed from an outer ring portion having a ball sliding contact surface and a plurality of balls slidably mounted between the inner ring portion and the outer ring portion. . 3. The handpiece for dental treatment according to claim 1, wherein a flange portion is formed at a lower end of the impeller, and a compressed air discharge passage is formed at a peripheral edge of a bottom portion of the turbine chamber.