JPH07328034A - Hand piece head with root canal length measuring function - Google Patents

Abstract

PURPOSE:To improve the operability of a hand piece by eliminating the external wiring of lead wires for a root canal length measuring circuit. CONSTITUTION:A fitting section 3 to a hand piece main body is electrically connected to a tool holding mechanism 9 via conducting members 4, 6, 7 in a head. When the tool holding mechanism 9 is combined with the hand piece main body storing or externally connected to a root canal length measuring circuit, a cutting tool fitted to the tool holding mechanism is connected to one signal circuit of the root canal length measuring circuit, thus no external wiring of lead wires for the measuring circuit is required, and a hand piece having good operability is obtained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a head attached to the tip of a handpiece and used in a treatment apparatus having a root canal length measuring function.

[0002]

2. Description of the Related Art A device in which a cutting tool such as a file or a reamer is also used as an electrode for measuring a root canal length so that a root canal treatment can be performed while measuring a root canal length is well known (for example, Japanese Utility Model Publication 57). -3303, JP-A-5-64643, etc.). In this case, the cutting tool will be used as the electrode of one of the signal circuits of the root canal length measuring circuit.
It is necessary to connect the leads for the measuring circuit to the cutting tool.

However, conventionally, the lead wire for the measuring circuit is connected via the outside of the handpiece, the lead wire obstructs the operability of the handpiece, and the lead wire is changed for each treatment. There is a problem in that work is troublesome because external wiring is required for the head for the handpiece.

[0004]

SUMMARY OF THE INVENTION The present invention has been made in view of this point and has been made for the purpose of improving the operability of a handpiece by eliminating the external wiring of a lead wire for a root canal length measuring circuit. .

[0005]

In order to achieve the above object, the present invention is provided with a tool holding mechanism for mounting a cutting tool, which is mounted on the tip of a handpiece with a root canal length measuring function. In a head used as a head, a mounting portion of the handpiece body and a tool holding mechanism are electrically connected to each other through a conductive member inside the head.

The above electrical connection is made via a driving force transmission mechanism for transmitting the rotation of the motor transmitted from the handpiece body to the tool holding mechanism.

A gear mechanism can be used as the driving force transmission mechanism. In this case, it is desirable to provide an urging means for urging the gear mechanism with a pressing force, and an elastic body is used as the urging means. .

Further, as the driving force transmission mechanism, a conversion mechanism for converting continuous rotation of the motor into reciprocating rotary motion and transmitting it to the tool holding mechanism can be used.

The above electrical connection can also be made via a brush mechanism.

Further, a contact piece for abutting the cutting tool mounted on the tool holding mechanism is provided, and the mounting portion on the handpiece main body and the tool holding mechanism are electrically connected through a conductive member inside the head. There is.

Further, in each of the above heads, at least the head housing and the outer surface of the tool holding mechanism are made of an insulating material.

[0012]

The handpiece head with a root canal length measuring function of the present invention is mounted on the tool holding mechanism by combining it with the handpiece body which has a signal circuit for root canal length measurement built therein or which is provided externally and connected. Since the cutting tool conducts to one of the root canal length measuring circuits through the conductive member inside,
There is no need to externally connect the measuring circuit lead wire to the handpiece head.

By making an electrical connection between the mounting portion to the handpiece body and the tool holding mechanism via the driving force transmission mechanism in the head, the head of the present invention can be obtained without requiring any special parts. The head of the present invention can be easily obtained by using a gear mechanism that can be realized and is usually provided in the head as the driving force transmission mechanism. Further, by providing the gear mechanism with the urging means for urging the pressing force, the mutual contact of the gears is maintained even during operation, and the connection is ensured.

Even when a conversion mechanism for converting continuous rotation into reciprocating rotary motion is used as the driving force transmission mechanism, the head of the present invention can be realized without requiring special parts.

Further, by making the above electrical connection via the brush mechanism, the connection is secured.

Further, in the case where a contact piece that comes into contact with the cutting tool is provided for electrical connection, the connection is reliable because it does not pass through the movable part.

Further, by forming the outer surface of the insulating material, the measuring circuit is not affected even if a part of the head comes into contact with the patient, and the root canal length measurement can be continued without any trouble.

[0018]

EXAMPLES Next, examples of the present invention will be described.

FIG. 1 shows a first embodiment. Reference numeral 1 denotes a head, a bearing holder 3 is fixed to a head housing 2, and a drive shaft 4 is supported by the bearing holder 3. 5 is a drive gear fixed to the input side end of the drive shaft 4,
6 is a front gear fixed to the output side end of the drive shaft 4,
Reference numeral 7 is a rotor shaft to which a rotor gear 8 is fixed. The drive shaft 4 and the rotor shaft 7 are arranged orthogonally to each other so that the front gear 6 and the rotor gear 8 mesh with each other. The cutting tool 10 is attached to the tool holding mechanism 9 provided at the upper end of the rotor shaft 7 for use. It

The above is a general structure which has been conventionally known, and a well-known one can be appropriately adopted as the tool holding mechanism 9, and the bearing can be directly attached to the tip of the main body of the handpiece or via a shank. When the holder 3 is inserted, the drive gear 5 meshes with the gear on the main body side, the rotation of the motor is transmitted, and the cutting tool 10 rotates.

In this embodiment, all of the bearing holder 3, the drive shaft 4, the bearing 4a supporting the drive shaft 4, the front gear 6, the rotor shaft 7, and the rotor gear 8 are made of metal or other conductive material. A continuous circuit is formed by the members, and the bearing holder 3 and the tool holding mechanism 9 are electrically connected. Therefore, by mounting the head 1 of this embodiment on the handpiece body in which the bearing holder 3 is entirely or at least partially formed of a metal or other electrically conductive material, the tool holding mechanism 9 is operated. The piece is brought into conduction with the conductive member of the body.

Therefore, when this conductive member is combined with the handpiece body in which one of the root canal length measuring circuits is connected, the cutting tool 10 mounted on the tool holding mechanism 9 is rooted through the conductive member inside the head. The pipe length measuring circuit is electrically connected to one of the signal circuits, and it is not necessary to purposely wire and connect the measuring circuit lead wire to the outside of the handpiece head. The handpiece main body incorporating the above-mentioned signal circuit will be described later.

In the above example, part of the signal transmission circuit passes through the front gear 6 and the rotor gear 8. Therefore, if the two gears are momentarily separated from each other while the gears are rotating, the conduction may be interrupted. There is. In order to prevent this, in this embodiment, the front gear 6 is pressed to maintain contact with the rotor gear 8. That is, 11 is a wave washer for applying this pressing force, which is inserted between the bearing holder 3 and the bearing 4 a of the drive shaft 4. Therefore, the drive shaft 4 is pressed in the leftward direction in the figure, and the urging force of the drive shaft 4 causes the front gear 6 and the rotor gear 8 to rotate.
Therefore, the contact between the gears 6 and 8 is reliably maintained even during rotation.

A member that can be accommodated in a small space is desirable as the urging means for urging the pressing force to both gears 6 and 8. In addition to the above-mentioned wave washer, for example, a spring such as a coil spring or a disc spring or An elastic body such as rubber is suitable.

FIG. 2 shows a second embodiment, in which a signal transmission circuit is constructed via a brush mechanism. That is, the brush mechanism 15 including the brush 15a, the pressing spring 15b, and the set screw 15c is provided in the head housing 2, and the brush 15a is brought into contact with the outer peripheral surface of the rotor shaft 7. In the above-described first embodiment, the head housing 2
Since it is not an essential member of the conduction circuit, it is possible to use an insulating material such as synthetic resin, but in this embodiment, the head housing 2 is also formed of a conductive material such as metal.

As described above, by electrically connecting the head housing 2 and the rotor shaft 7 by using the brush mechanism 15, the two gears are momentarily separated from each other as in the case where a part of the conduction circuit is a gear mechanism. There is no possibility that the circuit will be interrupted during rotation, and conduction will be ensured, and stable measurement will be facilitated.

FIG. 3 shows an embodiment of a head of the type in which the rotor shaft 7 is twisted by a conversion mechanism for converting continuous rotation into reciprocating rotary movement. That is, a long hole 7a is formed in the outer peripheral surface of the rotor shaft 7 in the axial direction, and in response to this, a drive body 16 having an eccentric convex portion 16a instead of the front gear is fixed to the drive shaft 4, and Convex portion 1 in hole 7a
6a is engaged. Therefore, when the drive shaft 4 rotates, the convex portion 16a makes a circular motion, and accordingly, the rotor shaft 7 repeats reciprocating rotation within a certain range. Also in this embodiment, since the head housing 2 and the rotor shaft 7 are electrically connected by the brush mechanism 15 as in the case of FIG. 2, stable measurement can be performed without interruption of electrical connection.

In FIG. 4, unlike the above-described embodiments, a conduction circuit is formed without passing through the driving force transmission mechanism. That is, 17 is a contact piece made of a conductive plate material having a high elasticity such as phosphor bronze, and is fixed to the head housing 2 with a fixing screw 17b. As shown in (b) of the figure, a V-shaped notch 17a is formed at the tip, and the cutting tool 10 mounted on the tool holding mechanism 9 is inserted into the notch 17a and a predetermined contact is made. Contact piece 17 under pressure
And the cutting tool 10 are in contact with each other. Also in this embodiment, the head housing 2 is made of a conductive material such as metal.

With the above structure, the head housing 2 and the contact piece 1 are provided between the bearing holder 3 and the cutting tool 10.
Since it is not necessary to wire the measuring circuit lead wire from the outside to connect to the cutting tool 10, there is no need for a moving part such as a gear to ensure conduction.

By the way, since the head 1 is inserted into the oral cavity of a patient, touching a tissue such as the oral cavity may affect the root canal length measuring circuit and cause a problem such that measurement cannot be performed. In each of the above-mentioned embodiments, an insulating film is formed on the outer surface of the tool holding mechanism 9. Further, in the embodiment of FIG. 1, the entire head housing 2 can be made of an insulating material such as synthetic resin,
When a conductive material such as metal is used, an insulating film is also formed on the outer surface of the head housing 2.
In this embodiment, since the head housing 2 is made of a conductive material, an insulating film is formed on its outer surface. With this, even if the head 1 touches the tissue such as the oral cavity, the measurement can be performed without any trouble. Since these insulating films may be very thin, they are not shown in the figure.

The head of the present invention exerts its intended action and effect when it is combined with at least a handpiece body which has a root canal length measuring circuit built in or externally connected thereto. Examples of such a handpiece will be described below.

In FIGS. 5 and 6, reference numeral 21 denotes a main body, 22
Is a shank, and in this embodiment, the head 1 is attached to the main body 21 via the shank 22. Two
Reference numeral 1a is a motor housing, 21b is a cover, and a motor 23 having a clutch 23b at the tip of an output shaft 23a is built in the motor housing 21a, and one end is provided with a stationary controller (not shown). A connecting tube 24 connecting between the two is attached, and a head portion 25 to which the shank 22 is fitted is provided at the other end portion, that is, the tip end side.

A display unit 26 for displaying the result of root canal length measurement and an operation switch 27 for turning the cutting tool on and off and starting and stopping the measurement are provided on the outer peripheral portion.
As the display unit 26, for example, a plurality of LEDs are arranged and information is displayed by lighting or blinking the LEDs.

The tube 24 is provided with a water injection tube 24a, an air tube 24b, a motor lead wire 24c, a control lead wire 28 for the display section 26 and an operation switch 27, and is separate from the handpiece. A signal lead wire 29 electrically connected to one signal circuit of the root canal length measuring circuit provided outside is provided. The water injection tube 24a is connected to the joint 31, communicates with the opening 25a on the outer peripheral surface of the head 25 via the water pipe 32a, and similarly, the air tube 24b is connected to the joint 31 and the outer periphery of the head 25 via the air pipe 32b. It communicates with the opening 25b of the surface, and the signal lead wire 29 is also connected to the joint 31. Although a specific connection path is not shown, the motor lead wire 24c is connected to the motor 23 via the terminal plate 33, and the control lead wire 28 is connected to the display section 26 and the operation switch 27.
It is connected to the.

The above-mentioned joint 31 and each pipe 32a, 32b
The head 25 is made of metal, and the O-rings 34a and 34b provided at both ends of the pipes 32a and 32b and the O-ring 35 attached to the outer periphery of the head 25 are made of conductive rubber. Is used. Therefore, the signal lead wire 29 and the head portion 25 are connected to the joint 31, the O-rings 34a, 3
4b and the pipes 32a, 32b, etc., so that they are electrically connected to each other.

The shank 22 is connected to the housing 41 by the connecting cylinder 4
2 and the body 43 are integrally assembled, and the drive shaft 44 is supported at the shaft center portion. The drive shaft 44 is provided with a clutch 44a at one end and a drive gear 44b at the other end. When the connecting cylinder 42 is fitted into the head portion 25 of the main body 21, the fixing spring ring 25c of the head portion 25 is engaged with the annular groove 42a of the connecting cylinder 42 and prevented from coming off, so that the main body 21 is rotatable. Can be installed with. The water injection pipe 45 communicates with the opening 25a of the main body 21 through the annular groove 45a, and an air pipe (not shown) provided in parallel with the water injection pipe 45 also communicates with the opening 25b of the main body 21 through the annular groove 46a. .

The body 43 has a cylindrical insertion hole 43a, and a ring member 47 having an eccentric groove 47a on its inner peripheral surface is attached to the outside. This ring member 47
The ball 47b is projected into and retracted from the insertion hole 43a by rotating, and the bearing holder 3 of the head 1 is inserted into the insertion hole 43a.
The head 1 is mounted on the shank 22 by engaging the ball 47b with the hole 3a on the outer surface when the head 1 is inserted into the shank 22. In this state, the drive gear 44b and the drive gear 5 of the head 1
Mesh with each other.

Here, the housing 41 of the shank 22,
The connecting tube 42 and the body 43 are made of metal, and the head 1
When the shank 22 attached with is attached to the head 25 of the main body 21, the bearing holder 3 of the head 1 is attached to the shank 22.
Since it is connected to the signal lead wire 29 of the main body 21 via the, the above-described desired operational effects are exhibited.

In the above case, the head 25 of the main body 21 and the connecting tube 42 of the shank 22 are surely brought into contact with each other by the O-ring 35 made of conductive rubber. In the above example, since the signal lead wire 29 and the head portion 25 are electrically connected to each other through the water pipe 32a and the air pipe 32b, the motor housing 21a and the cover 21b are not necessarily made of metal, but this structure is not necessary. It is just an example, and other structures can be adopted.

FIG. 7 shows another embodiment of the structure. The motor housing 21a and the cover 21b are made of metal, and one or a plurality of contact plates 21c each having a contact 21d attached to a leaf spring are provided on the cover 21b. The contact 21d is provided in contact with the fixing spring ring 25c. That is, since the fixing spring ring 25c is made of metal and contacts the body 43 of the shank 22 with a sufficient contact pressure due to its elasticity, this embodiment pays attention to this point and prevents the ring 25c from coming off. It is also used for conduction. As a result, the contact between the head portion 25 and the ring 25c, which is apt to be structurally insufficient, is compensated for by the contact plate 21c, so that electrical continuity is ensured and stable measurement is possible.

The contact plate 21c is not limited to the shape shown in the figure, and other suitable shapes can be adopted. Further, as described above, the contacts are fixed to the spring ring 25.
connection tube 42 of shank 22 rather than contacting c
The structure may be such that it is brought into direct contact with.

FIG. 8 shows an embodiment of a handpiece having no water and air supply function. The same parts as those in FIG. 5 are designated by the same reference numerals, and different points will be described.
In this embodiment, since the structure relating to water and air is not necessary, the structure is simple as a whole, and the body 43 is the housing 4 of FIG.
1 and the connecting cylinder 42 are also used. Also, the head 2 of the main body 21
5 is provided with a signal terminal 51 to which one signal circuit of the root canal length measuring circuit is connected.
Inside, there is provided a conduction spring 52 that is prevented from coming off by a retaining ring 52a.

That is, when the shank 22 is attached to the main body 21, the metal spring holder 4 of the shank 22 is provided with the conduction spring 52 by the end face of the head 25 of the main body 21.
The shank 22 and the main body 21 are electrically connected to each other by being pressed into contact with the end surface of 3a. The conduction spring 52 is preferably formed of a good conductor having a high elasticity such as phosphor bronze, and the shape thereof may be a coil spring as shown in the figure, a wave washer, a disc spring or the like.

The display unit 26 and the operation switch 27 provided in the main body 21 are for displaying the measurement result of the root canal length and the like, and for turning the cutting tool on and off, starting and stopping the measurement, etc. As described above, the shank 22 is the main body 21.
It is freely rotatable with respect to. Therefore, the display unit 26 and the operation switch 27 can be turned to a position where confirmation and operation can be easily performed, and only the head 1 can be arbitrarily rotated according to the site to be treated, and an easy-to-use handpiece can be realized. it can.

In each of the above examples, the shank 22
Since there is a possibility of touching the inside of the patient's mouth and lips, it is desirable to provide an insulating film on at least the outer surface of the possible range.

In the example of FIG. 8, since it is not necessary to supply water and air from the stationary control device through the tube, the main body 21 is equipped with a power supply battery and a root canal length measuring circuit, and the tubeless cordless It may be used as a handpiece.
Therefore, if the head 1 is combined with such a cordless type main body 21, the operation is not restricted by the tube, and the external wiring of the lead wire for the measurement circuit is not required, and the operability is excellent. The features of the present invention can be further exerted, and it is effective in further improving the usability of the treatment apparatus having the root canal length measuring function.

[0047]

As is apparent from the above description, in the handpiece head of the present invention, the mounting portion to the handpiece body and the tool holding mechanism are electrically connected through the conductive member inside the head. The cutting tool mounted on the tool holding mechanism can be connected to the root canal length measuring circuit through an internal conduction circuit by combining it with a handpiece body that has a root canal length measuring circuit built in or externally connected. It is connected to the signal circuit, eliminating the need for external wiring of the measuring circuit lead wires.

Therefore, the lead wire obstructs the operability of the handpiece, and since the lead wire has to be externally wired for each treatment, troublesome problems are solved and the operability of the handpiece is improved. Therefore, it is possible to obtain an easy-to-use root canal length measuring device.

Further, in the case where the above-mentioned signal transmission circuit is constituted via the driving force transmission mechanism in the head, the head of the present invention can be realized without requiring special parts.

Further, by utilizing a gear mechanism normally provided in the head as a driving force transmission mechanism and providing an urging means for urging a pressing force to the gear mechanism, mutual contact between the gears is maintained even during operation. The conduction circuit is maintained, and stable root canal length measurement is possible.

Also, when a converting mechanism for converting continuous rotation into reciprocating rotary motion is used as the driving force transmitting mechanism, the head of the present invention can be realized without requiring special parts.

Further, in the case where the conduction circuit is configured via the brush mechanism, the contact is better than that of the gear mechanism, and the conduction is ensured, and the stable root canal length measurement can be performed.

Further, in the case where the conduction circuit is constituted by providing the contact piece that comes into contact with the cutting tool, the conduction is ensured because the contact does not go through the movable portion where the contact is likely to be unstable, and the external wiring of the lead wire is unnecessary. The feature that exists is exhibited as it is.

Further, by forming the outer surface of the insulating material, the measuring circuit is not affected even if a part of the head touches the patient, and the root canal length measurement can be continued without any trouble.

[Brief description of drawings]

FIG. 1 is a sectional view of a first embodiment of the present invention.

FIG. 2 is a sectional view of a main part of the second embodiment.

FIG. 3 is a sectional view of a main part of a third embodiment.

FIG. 4 is a cross-sectional view of a main part of a fourth embodiment and a plan view of a tip of a contact piece.

FIG. 5 is a cross-sectional view of one embodiment of the body of a handpiece used in combination with the head of the present invention.

FIG. 6 is a cross-sectional view of one embodiment of a shank of a handpiece that is also used in combination.

FIG. 7 is a cross-sectional view of a main part of a modified example of the handpiece body.

FIG. 8 is a sectional view of another embodiment of a handpiece used in combination with the head of the present invention.

[Explanation of symbols]

 1 head 2 head housing 3 bearing holder 4 drive shaft 6 front gear 7 rotor shaft 8 rotor gear 9 tool holding mechanism 10 cutting tool 11 wave washer 15 brush mechanism 16 driver 17 contact piece 21 main body 22 shank 29 signal lead wire 51 signal Terminal 52 Spring for conduction

Claims (9)

[Claims] 1. A head, which is equipped with a tool holding mechanism for mounting a cutting tool, is used by being mounted on the tip of a handpiece with a root canal length measuring function, and which is mounted on a handpiece body. A head for a handpiece with a root canal length measuring function, which is electrically connected to a tool holding mechanism through a conductive member inside the head. 2. The electric connection between the mounting portion to the handpiece body and the tool holding mechanism is via a driving force transmission mechanism for transmitting the rotation of the motor transmitted from the handpiece body to the tool holding mechanism. The head for a handpiece with a root canal length measuring function according to claim 1, which is performed. 3. The handpiece head with a root canal length measuring function according to claim 2, wherein the driving force transmitting mechanism is a gear mechanism. 4. The head for a handpiece with a root canal length measuring function according to claim 3, wherein the gear mechanism is provided with an urging means for urging a pressing force. 5. The head for a handpiece with a root canal length measuring function according to claim 4, wherein the biasing means is an elastic body. 6. The root canal length measuring function according to claim 2, wherein the driving force transmitting mechanism is a converting mechanism for converting the continuous rotation of the motor transmitted from the handpiece body into a reciprocating rotary motion and transmitting the reciprocating rotary motion to the tool holding mechanism. Head for the attached handpiece. 7. The head for a handpiece with a root canal length measuring function according to claim 1, wherein the electrical connection between the mounting portion on the main body of the handpiece and the tool holding mechanism is performed via a brush mechanism. . 8. A head equipped with a tool holding mechanism for mounting a cutting tool, the head being mounted and used at the tip of a handpiece with a root canal length measuring function, the cutting being mounted on the tool holding mechanism. A head for a handpiece with a root canal length measuring function, characterized in that a contact piece that comes into contact with a tool is provided, and a mounting portion to a handpiece body and a cutting tool are electrically connected through the contact piece. 9. The head for a handpiece with a root canal length measuring function according to claim 1, wherein at least the outer surfaces of the head housing and the tool holding mechanism are made of an insulating material.