JPH11104148A - Hand-piece for dental sandblast - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a turbine for a turbine hand-piece from becoming contaminated by grinding powder when connecting the hand-piece for dental sandblast which jets the grinding powder and the turbine hand-piece to a dental hose in an interchangeable manner. SOLUTION: In this hand-piece 10 for dental sandblast comprising a powder container 24 which stores grinding powder, a compressed air feed ductwork 32 which is open into the powder container 24, a joint part 16 which connects the upstream end of the compressed air feed ductwork 32 to a dental hose 18 extending from a dental unit in such a manner that the hose 18 is interchangeable with a dental turbine hand-piece 10 and a jet nozzle 58 which ejects a mixture of compressed air and the grinding powder, the compressed air feed ductwork 32 is internally equipped with a check valve 38 for checking the reverse flow of the grinding powder toward the joint part 16.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a handpiece for dental sandblasting in which a tooth is polished or cut by spraying an abrasive powder such as a baking soda powder or an alumina powder on the tooth.

[0002]

2. Description of the Related Art Japanese Patent Application Laid-Open No. 61-109560 discloses a powder container for storing grindable powder, a compressed air supply line for supplying compressed air to the powder container, compressed air and grindability. A handpiece for dental sandblasting comprising a spray nozzle for spraying a mixture with a powder is disclosed.

[0003] A hose joint is provided at the rear end of the sandblasting handpiece. When the sandblasting handpiece is connected to a dental hose extending from the dental unit, compressed air, water, electricity or electricity is supplied from the dental unit. Light energy is supplied.

[0004] Hose fittings allow a dentist to interchangeably connect a sandblasting handpiece, a turbine handpiece or other compressed air-operated dental handpiece to a single dental hose. The dental procedure is performed while changing the handpiece accordingly.

[0005]

In this kind of dental sandblasting handpiece, the inlet of the compressed air supply pipe provided in the handpiece is a female member of a hose joint (a member of the hose joint on the handpiece side). ), And the outlet thereof communicates with the powder container.

For this reason, when the handpiece is not used, the handpiece is sometimes held in such a position that the inlet of the compressed air supply pipe is lower than the outlet of the compressed air supply pipe. The powder flows back to the hose joint through the compressed air supply line, and the grindable powder flows on the inner periphery of the female member of the hose joint and, consequently, the male member of the hose joint (a member of the joint on the hose side). May contaminate the outer periphery of the device.

[0007] When the handpiece for sandblasting is removed from the dental hose in a state where the hose joint is contaminated with the abrasive powder and the turbine handpiece is connected to the hose, the powder is transferred from the male member of the hose joint to the turbine hand. Transfer to the female part of the piece joint and contaminate the compressed air supply line in the turbine handpiece.

The turbine of a turbine handpiece is generally
Since it rotates at a very high speed of 300 to 450,000 rpm, the bearing of the turbine is unacceptable if the compressed air supply line in the turbine handpiece is slightly contaminated with abrasive powder. May be damaged.

Further, since the abrasive powder increases the frictional resistance, if the abrasive powder adheres to the hose joint, it becomes difficult to smoothly attach and detach the handpiece, and the handpiece is attached to the hose. It becomes difficult to rotate.

It is an object of the present invention to provide a handpiece for dental sandblasting in which the hose joint is not contaminated by abrasive powder.

[0011]

SUMMARY OF THE INVENTION The present invention comprises a powder container for storing abrasive powder, a compressed air supply line opened to the powder container for supplying compressed air to the powder container, A joint for interchangeably connecting a dental turbine handpiece to a dental hose extending the upstream end of the compressed air supply line from the dental unit; and a connection between the compressed air and the abrasive powder in the powder container. In a handpiece for dental sandblasting having an injection nozzle for injecting the mixture, a check valve for preventing the abrasive powder from flowing back toward the joint portion is provided in the compressed air supply line. It is characterized by having.

Since the check valve is provided in the compressed air supply pipe as described above, regardless of the posture of the handpiece,
The grinding powder in the powder container is prevented from flowing toward the hose joint, and the hose joint is prevented from being contaminated by the grinding powder.

[0013] In a preferred embodiment, the downstream end of the compressed air supply line comprises an air supply tube projecting into the powder container, the air supply tube having a radially open air supply hole.
The check valve comprises an annular closure member formed of a resilient material, such as an elastomer, that is radially outwardly inflatable and is mounted around the air supply line to close the air supply hole. Preferably, the elastic closing member is constituted by two O-rings which are in contact with each other and are juxtaposed in the axial direction.

If the check valve is constituted by the annular closing member made of an elastomer as described above, since there is no movable portion, the check valve has excellent durability. Further, the check valve can be manufactured extremely simply and at low cost.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIGS. 1 and 2, a dental sandblasting handpiece 10 has an elongated handpiece body 12. In the embodiment shown, the body 12 comprises three parts screwed together,
It can take any other structure.

Formed at the rear of body 12 is a known type of female member 16 adapted to receive a standardized male member 14 of a hose connection. The male member 14 of the hose fitting is attached in a known manner to the end of a dental hose 18 extending from a dental unit (not shown). The male member 14 and the female member 16 form a hose joint.
As is well known, the male member 14 of the hose joint can be connected to the sandblasting handpiece 10 of the present invention, a conventional turbine handpiece and other compressed air-operated dental handpieces in a replaceable one-touch manner. it can.

A support portion 20 is formed below the main body 12, and a powder container 24 is attached to the support portion 20 using a nut 22. The powder container 24 can be composed of a cap 26 and a main body 28 screwed to each other. By loosening the main body 28 from the cap 26 and removing it, grindable powder such as baking soda powder or alumina powder can be removed from the container 24. Can be filled inside.

On the other hand, the compressed air supply port 30 of the male member 14 of the hose joint is connected to the powder container 24 by a compressed air supply line 32 so that compressed air is supplied into the powder container 24. Has become. In the illustrated embodiment, the compressed air supply line 32 includes a compressed air supply passage 34 formed in the main body 12 and an air supply tube 36 connected to the passage 34.

At the end of the compressed air supply pipe 36, the container 24
Check valve 3 for preventing the abrasive powder 39 in the inside from flowing back toward the hose joint through the compressed air supply line 32.
8 are provided.

Referring to the enlarged view of FIG. 3, in the illustrated embodiment, the check valve 38 has a main body 40 fixed to the tip of the air supply pipe 36 by press fitting or the like. The main body 40 has an axial passage 42 communicating with the air supply pipe 36,
Are formed with diametrically intersecting air supply holes 44.

An annular groove 46 is formed on the outer periphery of the main body 40, and the air supply hole 44 is opened in the annular groove 46. A pair of upper and lower O-rings 48 made of an elastomer are fitted in the annular groove 46 exactly.

The pair of O-rings 48 function as an elastic closing member or valve element for closing the air supply hole 44. When compressed air is sent from the compressed air supply line 32, the O-ring 48 has a radius. The compressed air expands outward in the direction to allow the compressed air to enter the powder container 24. However, when the supply of the compressed air is shut off, the O-ring 48 comes into close contact with the air supply hole 44, and the abrasive powder 39 is the air supply hole 4
4 is prevented from entering.

Referring to FIG. 2 again, when compressed air is supplied into the powder container 24, the abrasive powder 39 flies up in the container 24 and is sent to the mixing section 52 through the powder supply passage 50. Can be

In the preferred embodiment shown, the compressed air supply port 30 of the male member 14 of the hose connection, on the other hand, communicates with the mixing section 52 via a bypass passage 54. The grindable powder supplied from the powder supply passage 50 and the compressed air supplied from the bypass passage 54 are mixed in a mixing section 52.
The mixture is injected from the injection nozzle 58 through the mixing pipe 56. In order to prevent the powder in the mixing section 52 from moving toward the hose joint via the bypass passage 54 when the handpiece is not used, a check valve 55 that is spring-biased is also provided in the bypass passage 54. is there.

The handpiece body 12 is also provided with a water supply pipe 60, and if necessary, water is further added to a mixture of the powder and the compressed air injected from the injection nozzle 58 to remove the mist. It can be formed. The inlet of the water supply line 60 communicates with the water supply port 62 of the male member 14 of the hose joint. The outlet of the water supply line 60 is connected to the outer line of the nozzle 58 having a double pipe structure as shown in FIG. They are in communication.

Prior to using the handpiece, the powder container 2
4 is loosened and removed from the cap 26, and the grindable powder 39 is introduced to a desired level.
Is screwed into the cap 26. Baking soda powder can be used for polishing teeth and dentures, and alumina powder can be used for cutting.

When the sandblasting handpiece 10 is connected to the hose 18 from the dental unit and a foot switch (not shown) of the dental unit is operated to supply compressed air to the handpiece 10, the compressed air is It enters the powder container 24 while pushing and opening the pair of O-rings 48. The abrasive powder 39 in the powder container 24 is sent to the mixing section 52 and mixed with the compressed air, and the mixture is injected from the injection nozzle 58. The dentist can supply water by operating a foot switch as needed, and can also spray a mist of powder, compressed air, and water.

When the dental treatment is completed, the dentist presses the push-button shutoff valve 64 provided on the handpiece body 12 to shut off the compressed air supply passage 34 for only 2 to 3 seconds. As a result, only the compressed air from the bypass passage 54 is supplied to the mixing section 52, the mixing pipe 56, and the injection nozzle 58, so that the abrasive powder adhering to the inner walls thereof is blown off, and the mixing section 52 and the mixing pipe 56 and the injection nozzle 58 are cleaned.

When the supply of compressed air is stopped, the two O-rings 48 come into close contact with each other and come into close contact with the air supply hole 44, so that the abrasive powder enters the air supply pipe 36 when the sandblasting handpiece 10 is not used. Nothing. Further, the check valve 55 of the bypass passage 54 also closes when the supply of the compressed air is stopped.

[0030]

Thus, according to the present invention, the female member 16 on the sandblasting handpiece 10 and the male member 14 on the dental hose side of the joint of the dental hose are contaminated by the abrasive powder. Nothing. For this reason, even if the sandblast handpiece 10 is removed from the hose joint and a turbine handpiece or the like is connected instead, the compressed air supply pipe in the turbine handpiece and the female member of the joint of the turbine handpiece become abrasive. No contamination by powder.

Therefore, when the turbine handpiece is connected to the dental hose in a manner interchangeable with the sandblast handpiece, damage to the high-speed turbine of the turbine handpiece can be prevented, and the turbine handpiece can be securely connected. Therefore, the life of the turbine handpiece can be ensured.

Further, since the male member of the hose joint and the female member of the joint of the handpiece are not contaminated by the abrasive powder, the detachment and rotation of the handpiece can be performed smoothly.

When the closing member of the check valve is formed of an elastic member such as an O-ring, since there is no movable portion, excellent durability can be obtained, and it can be manufactured easily and inexpensively.

[Brief description of the drawings]

FIG. 1 is a side view of a handpiece for dental sandblasting of the present invention, showing a hose joint separated from the handpiece.

FIG. 2 is a cross-sectional view of the handpiece shown in FIG. 1, showing a state where the handpiece and a hose joint are connected.

FIG. 3 is an enlarged sectional view of a check valve of the handpiece shown in FIG. 2;

FIG. 4 is an enlarged sectional view of a nozzle of the handpiece shown in FIG. 1;

[Explanation of symbols]

 10: Handpiece for dental sandblasting 14/16: Hose joint 24: Powder container 32: Compressed air supply line 38: Check valve 44: Air supply hole of check valve 48: Elastic closing member (O-ring) 55: No. 2 check valve 58: injection nozzle

Claims (4)

[Claims] 1. A powder container for storing abrasive powder, a compressed air supply line opened to the powder container for supplying compressed air to the powder container, and a compressed air supply line. A joint for interchangeably connecting the dental turbine handpiece to a dental hose that extends the upstream end from the dental unit, and for injecting a mixture of compressed air and abrasive powder in a powder container. In the handpiece for dental sandblasting provided with an injection nozzle, the compressed air supply line is provided with a check valve for preventing the abrasive powder from flowing back toward the joint portion. Handpiece for dental sandblasting. 2. The downstream end of the compressed air supply line comprises an air supply tube projecting into the powder container, the air supply tube having a radially open air supply hole, and the check valve being provided with the supply valve. 2. A handpiece for dental sandblasting according to claim 1, wherein the handpiece comprises an annular resilient closure member mounted around the air supply tube to close the pores and expandable radially outward. 3. The handpiece for dental sandblasting according to claim 2, wherein the elastic closing member comprises two O-rings which are in contact with each other and are juxtaposed in the axial direction. 4. The hand for dental sandblasting according to claim 1, further comprising a bypass passage for supplying compressed air to the injection nozzle, wherein a second check valve is provided in the bypass passage. piece.