Pneumatic dental vibrator with replaceable vibrator module

Pneumatic dental vibrating appliance with replaceable vibrator module

Technical field

The present invention relates to improvements in hand-held pneumatic dental vibrating appliances such as pneumatic dental scrapers.

Generally, a powered dental vibration appliance includes an elongated housing suitable for being held by hand, a vibration device provided in the housing and used as a vibration source, and a dental vibration tool (such as Scratching head and root canal reaming device), the dental tool vibrates in response to the vibration generated in the vibrating device, so as to perform dental treatments such as scraping and root canal reaming.

The vibrators used in power dental vibrating appliances can be divided into two categories according to their working principles: electric vibrators, which use electrical energy to generate vibration; pneumatic vibrators, which use compressed air as a power source.

The first type of electric vibrator is disclosed in, for example, JP-A-59-25738 and JP-A-60-55941. The electric vibrator includes an electrostrictive or piezoelectric transducer, which generates vibration when an alternating voltage is applied. The advantage of electric vibrators is that since they can work at ultrasonic frequencies exceeding 20,000 Hz, they basically do not emit noise.

However, the problem with the electric vibrator is that there is a danger that the electromagnetic waves emitted by the electrostrictive or piezoelectric transducer may cause malfunction of medical electronic components, electrical devices and instruments (such as pacemakers).

In contrast, another type of pneumatic vibrator is designed to vibrate in response to the vibrating movement of a rotor or a vibrating element, the vibrating movement being caused by a compressed air flow provided by a dental treatment device. Therefore, the advantage of dental appliances equipped with pneumatic vibrators is that they have no problems related to the emission of electromagnetic waves.

However, two basic problems must be overcome in the design of dental appliances equipped with pneumatic vibrators.

The first problem is that moving parts such as rotors and vibrating elements inevitably wear out while working. This requires replacement of the rotor or the vibrating element when its service life expires. For this reason, it must be repaired by a dentist in a personal dental office or by a professional mechanic in a designated repair center.

The second problem is that since the rotor or vibrating element of the pneumatic vibrator may usually only vibrate at a frequency in the subsonic or audible sound wave range, it will produce very annoying audible sound or noise, which often makes the patient feel uncomfortable.

In order to discuss the prior art, US-E-29,687 (Sertich) discloses a dental scraper equipped with a pneumatic vibrator. The vibrator includes a tube shaft elastically supported in a housing and a sleeve-shaped rotor loosely and rotatably mounted on the tube shaft. When compressed air is sprayed tangentially toward the inner circumferential surface of the rotor through an air nozzle formed across the wall of the tube axis, the rotor rotates around the tube axis and vibrates it.

Sertich's dental scraper has the above-mentioned advantages of a pneumatic vibrator, that is, there are no problems caused by electromagnetic waves.

Moreover, since the rotor is freely installed on the tube shaft and is limited in the axial direction by a pair of spaced O-rings assembled on the tube shaft, whenever the rotor is worn or damaged, only the tube shaft needs to be taken out The rotor can be easily replaced by removing the outer shell and the O-ring. Since the replacement of the rotor can be easily completed by the user in this way, there is no maintenance problem.

However, the problem with this dental scraper is that the pneumatic vibrator therein can only generate vibrations with a frequency as low as 3000-6000 Hz. This is because the vibration occurs in a so-called bending or flexural vibration mode, in which an elongated tube shaft is vibrated by the bending or flexural motion of the tube shaft under the action of a rotating rotor. Therefore, the dental curette cannot solve the above-mentioned problem of the pneumatic vibrator, that is, it generates annoying noise that makes the patient uncomfortable.

US-A-4,453,919 (Takeshita) describes a structure and working principle of different types of pneumatic vibrators that can be installed in a dental scraper and used as a vibration source. The vibrator includes a shell with a disc-shaped working chamber (or rotor chamber), a disc-shaped vibrating element (or rotor) movably contained in the working chamber, and a nozzle for tangentially injecting compressed air into the working chamber.

Since compressed air is injected into the working chamber through the nozzle, the vibrating element vibrates while it rotates, thereby impacting the wall of the working chamber to generate vibration. The vibration generated by the vibrator is transmitted to a scraping head through a shaft. It can be considered that the transmission of vibration through the axial scraping head is a combination of flexural mode vibration and sound or elastic wave mode vibration.

US-A-5,190,456 (Hasegawa) aims to improve the tooth scraper described in US-A-4,453,919 (Takeshita), and proposes to increase the vibration frequency of the vibrator as close to the ultrasonic range as possible to reduce the traditional pneumatic vibrator The inherent annoying noise.

To this end, the shaft is shortened to transmit sound or elastic mode vibration proportionally larger than the flexural mode vibration to the scraping head, and the shaft is supported in such a way as to avoid the existence of vibration nodes that will Causes flexural mode vibration.

According to the concept of US-A-5,190,456 (Hasegawa), by reducing the size of the vibrating element (rotor) as much as possible, the vibration frequency can be increased to close to the ultrasonic range, thereby avoiding annoying noise. For example, with a vibration element as small as 5 mm in diameter, the vibration frequency will be increased to about 15000 Hz, which can significantly reduce the audible noise.

However, increasing the vibration frequency will also accelerate the wear of the vibrating element and the side wall. In addition, in order to increase the vibration frequency to the extent close to the ultrasonic range, the more the size of the vibrating element is reduced, the more obvious and serious the abrasion effect produced on the vibrating element will be, which will also shorten the service life of the element. As a result, the vibrating element and the side wall have to be replaced more frequently.

However, compared with the tooth scraper described in US-E-29,687 (Sertich) (the vibrating rotor can be easily replaced by anyone, as described above), the one described in US-A-5,190,456 (Hasegawa) In the case of a dental curette, it is difficult for ordinary users (such as dentists) to smoothly replace the vibrating element and related wearable parts.

This is firstly because it is difficult to take out the vibrating device as a whole because the vibrating device is deeply installed in the elongated casing. A special clamp must be used to take out the vibrating device and install it into the housing.

The second difficulty is that the body of the vibrator is made of multiple components, including a pair of side plates that define the working chamber. Therefore, even if the vibrating device as a whole can be smoothly taken out of the housing, the user must further disassemble the vibrator body into parts to replace the vibrating element. It is also necessary to use a special tool to disassemble and reassemble the vibrator body, which is usually difficult for ordinary users to complete.

Third, in the vibrator described in US-A-5,190,456, it is very important that the vibrating element cooperates well with the side plate during vibration to effectively generate high-frequency vibration. It is often encountered that simply replacing the vibrating element or the side plate is not enough to restore the output performance of the vibrator.

For these reasons, for users of the scraper described in US-A-5,190,456, they must transport their scraper to a remote repair center or factory, and a professional mechanic will replace the worn parts or the entire vibration. Device. This caused inconvenience to the user, who had to interrupt the use of their scraper until the scraper was repaired and returned to the user.

Another object of the present invention is to provide a pneumatic dental vibrating appliance, which encourages users to perform self-maintenance and replace the vibrating device as a whole whenever it is necessary to replace the vibrating element and/or related parts.

The present invention provides a pneumatic dental vibrating appliance, comprising: an elongated housing with a longitudinally extending chamber defined to be continuous with the front end of the housing; the housing is divided into a main body and a front cover, which are connected, for example, by threads Are detachably connected to each other; a pneumatic vibrator module or an integral assembly that is replaceably accommodated in the chamber, the module has a vibrating element that generates vibration, and the module has a vibrating tool that is detachably connected to the module The front screw connection device; the device that elastically supports the module in the housing; the axial positioning device that positions the vibrator module against the front cover; the device that delivers compressed air to the vibrator module to excite the vibrating element; and An anti-rotation device that prevents the vibrator module from rotating relative to the housing when the vibrating tool is screwed onto or unscrewed from the vibrator module. The terms "front" and "rear" used herein refer to the viewing direction of the user of the appliance during use.

According to the present invention, the axial position of the joint between the main body and the front cover is selected such that when the main body and the front cover are separated from each other for replacement of the vibrator module, at least a part of the vibrator module is exposed to the main body or Outside the front cover, to allow the operator to hold the module with his fingers to take the module out of the main body or the front cover.

With this structure, when the user realizes that the power output of the pneumatic vibrator installed in the dental appliance is reduced due to the wear of the vibrating element or related parts, the user can loosen the threaded connection of the housing to separate the main body and the front cover from each other. When the main body is separated from the front cover, the vibrator module will remain connected to the main body or the front cover (depending on the situation), and the front or rear part of the vibrator module will be exposed to the main body or front cover to which it is connected. This will make the user think that the vibrator module is designed to be replaceable, and will visually encourage the user to replace it with a new one.

After such encouragement, the user uses the fingers of one hand to hold the exposed part of the vibrator module, and the other hand to hold the main body or the front cover, and only need to pull the module and the main body (or front cover) apart. A simple way to remove the module from the main body or front cover. After simply installing a new vibrator module on the main body or the front cover and screwing the main body and the front cover to each other, the dental appliance can be reused. The used vibrator module can be disposed of or sent to a repair center for repair.

In this way, it is only necessary to separate the main body and the front cover from each other, hold the used vibrator module to remove it from the main body or the front cover, install a new vibrator module in it, and make the main body and The front covers are screwed to each other, and the entire vibrator module can be replaced. Because all these operations can be performed by hand without special tools or fixtures, the module can be replaced very conveniently and quickly.

Therefore, for example, when the power of the vibrator is reduced due to the wear of the vibrating element, the user can immediately replace the vibrator module, thus avoiding the time loss caused by the need to send the dental appliance for repair and retrieve the repaired appliance. .

The user can be equipped with one or more spare vibrator modules that have been tested to a predetermined performance level after assembly. Therefore, the replaced module can always generate the required high level of vibration energy.

In an embodiment of the present invention, the anti-rotation mechanism is adapted to lock the vibrator module to the front cover. When the main body and the front cover are separated from each other, this will keep the vibrator module connected to the front cover. The axial length of the front cover is made shorter than the axial length of the vibrator module, and is preferably substantially equal to half of the axial length. With this structure, when the main body and the front cover are separated from each other, the rear half of the vibrator module will be exposed outside the front cover, thereby allowing the user to firmly and conveniently hold the module when the module is taken out of the front cover.

In this embodiment where the anti-rotation mechanism locks the vibrator module to the front cover, when the vibrating tool is screwed to or unscrewed from the vibrator module, the torque applied to the vibrating tool will be borne by the front cover. Therefore, when the vibration tool is screwed to or unscrewed from the vibrator module, there is a danger of over-tightening and loosening the front cover on the main body.

In order to avoid this inconvenience, according to a preferred embodiment of the present invention, the anti-rotation mechanism is designed to lock the vibrator module to the main body of the housing. With this structure, the torque applied to the vibrating tool to screw the vibrating tool to or from the vibrator module will be borne by the main body, and therefore the front cover will not be subjected to torque. This prevents the front cover from being over-tightened or loosened accidentally.

In this embodiment where the anti-rotation mechanism locks the vibrator module to the main body, when the main body and the front cover are separated from each other, the vibrator module will remain connected to the main body. The axial length of the front cover can be made shorter than the axial length of the vibrator module, preferably substantially equal to half, to ensure that the front half of the vibrator module is exposed outside the main body when the module is taken out of the front cover, thereby facilitating operation Hold by the person.

In another preferred embodiment of the present invention, the axial positioning device includes a positioning sleeve axially extending in the housing and fixed to the main body, and the anti-rotation mechanism is adapted to lock the vibrator module to the positioning sleeve, This ensures that the vibrator module remains connected to the positioning sleeve when the front cover is separated from the main body. Moreover, the contact point between the main body and the front cover is located behind the front end of the positioning sleeve to ensure that the front part of the vibrator module is exposed to the outside of the positioning sleeve when the main body and the front cover are separated from each other.

In this embodiment, since the contact point between the main body and the front cover is moved to the rear of the anti-rotation mechanism, the operator can use the dental appliance to hold a thinner part with his fingers. This facilitates the operator's grip and facilitates accurate positioning of the appliance during dental treatment.

Preferably, the axial length of the front cover is made greater than half of the entire axial length of the housing. More preferably, the front cover is made long enough to substantially cover the entire length of the appliance. It can be noted that it is easy to autoclave and ultrasonically clean the front cover separated from the vibrator module. By increasing the length of the front cover to substantially cover the entire length of the dental appliance and frequently disinfecting the front cover, the appliance can be kept cleaner and more hygienic.

Preferably, the anti-rotation mechanism includes at least one notch formed on the inner peripheral surface of the main body and at least one corresponding protrusion provided on the outer peripheral surface of the vibrator module to cooperate with the notch. With this structure, the vibrator module can be easily embedded in the front cover or the containing chamber of the main body. Preferably, the outer peripheral surface of the vibrator module forms a polygonal cross-section, and more preferably forms a hexagonal cross-section. This allows the user to assemble the module in the front cover or main body only after applying a limited relative angle action.

The above and other features and advantages of the present invention will be reflected from the following description.

With reference to these drawings, the scraper 10 is designed in the form of a dental handpiece, which is adapted to be connected to a dental treatment device (not shown) through a dental hose 12 to obtain compressed air and water therefrom.

The dental scraper 10 has a hand-held elongated tubular housing 14 in which a pneumatic vibrator module or assembly 16 is replaceably accommodated. When the handpiece is used as a dental scraper, a traditional dental scraper 18 can be detachably mounted on the front end of the vibrator module 16 as a vibrating tool. Alternatively, when the handpiece is used to ream the root canal, a traditional reamer or a dental file (not shown) can be installed in the vibrator module or assembly 16 instead of the scraping head 18.

The housing 14 is divided into a short front cover 22 with an external thread 20 (FIGS. 3 and 6A) and an elongated body 26 with an internal thread 24 (FIG. 3). The front cover 22 and the body 26 The housing 14 is formed by screw connection in a detachable manner.

The front cover 22 has a stepped axial hole 27, and the shape of the vibrator module 16 is made to be partially embedded in the stepped hole 27 with a small gap.

As shown most clearly in FIGS. 2 and 6A, the axial length of the front cover 22 is substantially equal to half of the vibrator module 16. Therefore, when the vibrator module 16 is installed on the front cover 22, only the front half of the vibrator module 16 is accommodated in the front cover 22, and the rear half of the module is exposed outside the front cover 22, as shown in FIG. 6B.

The vibrator module 16 is generally designed to work according to the working principle described in the above-mentioned US-A-4,453,919 (Takeshita), and is specifically designed to be similar to the vibrator structure described and shown in US-A-5,190,456 (Hasegawa). Therefore, the disclosures of these patents are incorporated herein for reference, and the working principle and overall structure of the vibrator module 16 are only briefly described below.

3, the vibrator module 16 includes a metal shell 28 in the form of a stepped cylinder, which has an axial hole 30, in which a disc-shaped first side plate 32 and an air jet ring are installed in sequence. 34 and a disc-shaped second side plate 36. These parts 32, 34 and 36 are held together by a retaining screw 38 screwed into the housing 28.

The inner surface of the side plates 32 and 36 and the inner peripheral surface of the air jet ring 34 define a disc-shaped working room or rotor chamber 40, which can vibrately accommodate a rotor or vibrating element 42 in the form of a perforated disc. . The outer diameter and axial thickness of the vibrating element or rotor 42 are respectively selected to be slightly smaller than the inner diameter and axial size of the working chamber 40 to allow the vibrating element 42 to vibrate or oscillate in the working chamber 40.

In order to improve the wear resistance, the side plates 32 and 36 and the rotor 42 are preferably made of cemented carbide such as high-speed steel and subjected to appropriate surface hardening treatment.

It is desirable to make the size of the vibrating element 42 as small as possible so that the vibrator operates at a vibration frequency higher than 15000 Hz, which is close to the ultrasonic range. A preferred axial thickness of the vibrating element or rotor 42 is about 0.4-0.8 mm, and a preferred outer diameter thereof is about 5-8 mm.

The vibrator module 16 can be provided to the user in the form of a disposable module or a movement, and the user cannot loosen the retaining screw 38 and disassemble it into parts to replace the vibrating element 42.

The air blowing ring 34 has a plurality of (for example, three) nozzles 44 which are equally spaced apart from each other in the circumferential direction. Although only shown schematically in FIG. 3, these nozzles 44 are arranged to open tangentially into the working chamber 40 to ensure that the air flow injected into the working chamber 40 through the nozzles 44 generates a strong swirling air flow therein. As described and represented in US-A-4,453,919 and US-A-5,190,456.

In order to deliver compressed air to the nozzle 44, the housing 28 of the vibrator module 16 has a groove 46 extending in the circumferential direction along its inner circumference facing the nozzle 44, and the groove is further separated from a plurality of circumferentially spaced ones. The open air inlet 48 (see also FIG. 6C) communicates. The manner in which compressed air is delivered to these inlets 48 will be described later.

In order to supply water for cooling and cleaning the scraping head 18 and teeth during the scraping operation, a water supply pipe 50 is provided, which extends through the housing 28, the side plates 32 and 36, and the central opening of the retaining screw 38, respectively. The vibrating element 42 also has a central opening to ensure that the vibration of the vibrating element is not disturbed by the water pipe 50.

The front end of the water pipe 50 is opened into an internally threaded hole 54 (FIG. 3) formed in the small-diameter end shaft portion 52 of the housing 28, and the externally threaded connection portion 53 (FIG. 1) of the scraping head 18 is screwed. The water pipe 50 and the housing 28 are sealed to each other by one or more O-rings 56 (Figure 3).

In order to prevent the vibrating element 42 from adhering to the inner surfaces of the side plates 32 and 36 when the vibrator is not working, a pair of shaft sleeves 58 and 60 are press-fitted in the center holes of the side plates 32 and 36, their axial length Slightly larger than the axial thickness of the side plate. The details of the bushing are described in US-A-5,997,172, the disclosure of which is incorporated herein by reference.

The air used in the working chamber 40 is also discharged through the inner space of the sleeve 60 and the central opening 62 of the holding screw 38, and the opening 62 is thus also used as an exhaust port.

As shown most clearly in FIG. 3, the axially extending stepped hole 27 of the front cover 22 has a rearward positioning shoulder, and the vibrator housing 28 correspondingly has a positioning shoulder 66 opposite to the shoulder 64 . An O-ring 70 is installed in an outer groove 68 formed on the housing 28. A positioning sleeve 90 presses the vibrator module 16 against the front cover 22 so that the O-ring 70 is properly pressed between the shoulders 64 and 66, so that the vibrator module 16 can be axially positioned relative to the front cover 22 .

The O-ring 70 is used to isolate the front cover 22 and the vibrator module 16 from vibration, and is used to airtightly seal the front cover 22 and the housing 28 with each other. Another O-ring 72 may be used to elastically support the end shaft 52 of the housing 28 with respect to the front cover 22.

An anti-rotation structure must be provided to prevent the vibrator module 16 from being unfavorable relative to the housing 14 when the scraping head 18 is screwed to or unscrewed from the threaded hole 54 formed in the end shaft 52 of the housing 28 of the module 16 Rotate. In the first embodiment, the housing 28 is locked to the front cover 22 during rotation. To this end, as shown in FIGS. 3 and 5, an intermediate portion 76 having an elliptical cross-section is provided between the end shaft 52 and the large-diameter portion 74 of the housing 28, and the inner peripheral surface 77 of the front cover 22 is shaped to have A complementary elliptical cross-section to ensure that the side surface of the elliptical portion 76 of the rotator housing 28 is in contact with the inner peripheral surface 77 of the front cover 22, thereby restricting the rotation of the housing 28 relative to the front cover 22. An elastic O-ring 80 can be installed in the outer groove 78 of the elliptical portion 76 to prevent the vibration of the module 16 from being transmitted to the front cover 22 through the portion 76.

1 and 2, the dental curette 10 is connected to a dental hose 12 extending from a dental treatment device (not shown) in a conventional manner. To this end, the first part 82 (for example, a male part) of a conventional hose connector is connected to one end of the dental hose 12, and the second part 84 (for example, a female part) is arranged on the main body 26 of the housing 14. rear end. In the embodiment shown in Figures 1 and 2, the first connector on the hose 12 is in the form of a plug 82, which has a plug ball-lock quick-connect mechanism 85, and the second connector on the housing 14 is In the form of a socket 84, the socket has a joint-shaped hole 86 into which a plug 82 is inserted. The socket member 84 is inserted into the main body 26 snugly, and is held in place by a retaining screw 88 screwed into the main body 26.

The positioning sleeve 90 can be formed concentrically with the socket 84 as one body, as shown in FIG. The positioning sleeve 90 is used for axially positioning the vibrator module 16 against the front cover 22. Before the front cover 22 and the main body 26 are screwed to each other, the vibrator module 16 is partially inserted into the front cover 22, and an O-ring 94 is installed in an outer groove formed on the retaining screw 38 of the vibrator module 16 in. Once the front cover and the main body 26 are screwed to each other through the engagement of the threads 20 and 24, the positioning sleeve 90 presses and positions the vibrator module 16 against the front cover 22, as shown in FIGS. 2 and 3, and an O-ring 70 is pressed between the shoulders 64 and 66.

The front end of the positioning sleeve 90 is retracted back into the front end of the main body 26 of the housing 14. Therefore, a cavity 91 that opens forward is formed in the main body 26 between the front end of the main body 26 and the front end of the positioning sleeve 90. The cavity 91 cooperates with the stepped axial hole 27 of the front cover 22 to form a cavity 92 for accommodating the vibrator module 16.

An annular space 93 between the positioning sleeve 90 and the housing main body 26 serves as a compressed air passage. This configuration is beneficial to simplify the structure of the dental curette 10.

On the other hand, the annular space 93 communicates with the plug receiving hole 86 of the socket 84 through an air passage 96 (FIG. 2) formed in the socket 84 of the hose joint, and will be connected with the plug 82 of the hose joint when inserted into the socket 84 The air supply port 98 of the plug 82 communicates with each other. In addition, the annular space 93 communicates with the air inlet 48 of the vibrator housing 28, so the compressed air is delivered to the nozzle 44 of the jet ring 34 through the inlet 48 and the inner groove 46 of the housing 28.

The air used in the working chamber 40 will pass through the central opening 62 of the retaining screw 38 (Figure 2), the annular space 100 between the positioning sleeve 90 and the water pipe 50, and the air jet channel 102 formed on the socket 84 of the hose connector. Return to the dental hose 12.

Cooling and washing water can be conveyed through a central water channel (not shown) formed in the plug 82 of the hose connector in a conventional manner and through the water pipe 50 to a water channel 104 formed in the scraping head 18 (FIG. 1) , Thereby conveying to the scraping head 18. The rear end of the water pipe 50 is firmly supported by the socket 84.

In use, use a wrench to firmly screw the scraping head 18 into the threaded hole 54 of the vibrator module 16, and insert the plug 82 of the dental hose 12 into the socket 84 of the hose connector of the housing 14 to compress Air is delivered to the vibrator. When compressed air is sprayed tangentially into the working chamber 40 through the nozzle 44, a vortex airflow is generated in the working chamber 40, thereby oscillating the vibrating element 42 according to the principle described in US-A-4,453,919, thereby generating vibration. According to the principle described in US-A-5,190,456, the vibration generated by the vibrator module 16 is transmitted to the scraping head 18 so that it vibrates at a high vibration frequency close to the ultrasonic range.

When the scraper 10 is used, the vibrating element 42 and the side plates 32 and 36 are worn out, thereby reducing the power output of the vibrator 16. At that time, the user can easily replace the entire vibrator module 16 in the following manner.

First, screw the scraping head 18 with a suitable wrench and remove it from the vibrator module 16. Then, the user holds the front cover 22 and the main body 26 of the housing 14 with two hands respectively and unscrews the front cover 22 and the main body 26 until the front cover 22 is separated from the main body 26, as shown in FIG. 6A.

Since the vibrator module 16 is rotationally locked to the front cover 22 by the anti-rotation structure 76/77, when the front cover 22 and the main body 26 are unscrewed from each other, the water pipe 50 will be rotated relative to the O-ring 56 at the same time. Pull out the O-ring 56. Therefore, there is sliding friction at the contact point between the water pipe 50 and the O-ring 56. On the contrary, there is static friction at the contact points between the front cover 22 and the O-rings 70 and 72, which static friction is greater than the sliding friction applied between the water pipe 50 and the O-ring 56.

Therefore, when the front cover 22 is separated from the main body 26, the vibrator module 16 will remain connected to the front cover 22 due to the static friction of the O-rings 70 and 72, as shown in FIG. 6A. At this time, half of the vibrator module 16 will be exposed to the outside of the front cover 22 toward the rear. This will visually encourage the user to replace the vibrator module 16 with a new one. Since the rear half of the vibrator module 16 is exposed, it can be easily pinched with fingers.

Therefore, by holding the front cover 22 with the fingers of one hand, holding the vibrator module 16 with the fingers of the other hand, and pulling open the front cover and the module as shown in FIG. 6B, it is easy to vibrate The detector module 16 is separated from the front cover 22, as shown in FIG. 6C.

After that, only a new vibrator module needs to be installed on the front cover 22, and the front cover 22 and the main body 26 are screwed to each other, so that once the scraping head 18 is installed, the scraping head 10 can be used again.

In this way, according to the present invention, when the power of the vibrator is reduced due to the wear of the vibrating element and related parts, anyone can easily replace the vibrator module without requiring special jigs or tools. The used vibrator module can be disposed of or sent to a repair center.

Figures 7 and 8 show a variation of the dental curette embodying the present invention. This variation is different from the first embodiment only in that a traditional threaded hose joint is used to replace the ball lock type quick connection mechanism used in the first embodiment. Therefore, those parts similar to those of the first embodiment are denoted by the same reference numerals in FIGS. 7 and 8, and the description will not be repeated.

7 and 8 and only describe the different points, a male connector 84A embedded in the main body 26 of the housing 14 has an external thread 106, which is used to connect to a female connector 82A of the hose connector. Threads (not shown) are engaged. The female connector 82A may be a traditional four-hole standard component, for example.

The male connector 84A has a compressed air inlet 108 communicating with the air passage 96, a water passage 112 communicating with the water pipe 50, and a water inlet communicating with the water passage 112. The water inlet is covered by the air inlet 108 in FIG. 8 .

In use, the male connector 84A and the female connector 82A are screwed together, so as to connect the dental scraper to the dental hose 12. In other respects, the operation of the scraper and the way of replacing the vibrator module are the same as those described in the first embodiment.

Figures 9-11 show a dental curette according to a third embodiment of the present invention. The feature of this embodiment is that the vibrator module 16 is locked to the main body 26 during rotation. In FIGS. 9-11, those parts similar to those of the first embodiment are denoted by the same reference numerals, and the description will not be repeated.

Only the difference will be described. The threaded joint used to detachably connect the front 22 and the main body 26 includes an external thread 120 formed on the outer peripheral surface of the front part of the main body 26 and a threaded joint formed on the inner periphery of the rear part of the front cover 22. Internal thread 122.

In this embodiment, since the connecting thread 120 of the main body 26 is formed on the outside of the main body 26, the front cavity 91 of the main body 26 has a cylindrical inner peripheral surface 124 without any threads. This allows the inner peripheral surface 124 of the front chamber 91 to have a plurality of notches or recesses 126, for example six in number, which are equally spaced apart from each other in the circumferential direction. The central notch 126 can be easily formed, for example, by locally milling or drilling the inner peripheral surface of the cavity 91 in the axial direction.

Corresponding to the notch 126 formed on the inner peripheral surface 124 of the main body 26, a locking structure 128 with a hexagonal cross-section is formed between the housing 28 of the vibrator module 16 and the end shaft 52. In this embodiment, The end shaft is tapered to enhance the transmission of sound and vibration. The cross-sectional size of the locking structure 128 is selected so that the two-sided corners of the hexagonal cross-section are loosely engaged in the notches 126.

In order to replace the vibrator module 16, firstly, firmly hold the main body 26 with one hand, and at the same time loosen the scraping head 18 with a wrench, so that the scraping head 18 is separated from the vibrator module 16. Contrary to the first embodiment, since the vibrator module 16 in this embodiment is locked to the main body 26 by the anti-rotation structure 126/128, the front cover 22 will not be subjected to the torque exerted by the wrench. This can prevent the front cover 22 from being accidentally loosened when the scraping head 18 is loosened.

Then, screw the threads 122 of the front cover 22 and the threads 120 of the main body 26 by hand to separate the front cover 22 and the main body 26 from each other.

In the third embodiment, since the vibrator module 16 is locked to the main body 26 during rotation, as described above, there is static friction at the contact point between the water pipe 50 and the O-ring 56, and when the front When the cover 22 and the main body 26 are unscrewed from each other, sliding friction will be generated at the contact point between the front cover 22 and the O-rings 70 and 72. Therefore, when the front cover 22 is separated from the main body 26, the vibrator module 16 will remain connected to the main body 26, as shown in FIG. 10.

Therefore, by holding the main body 26 with the fingers of one hand, and holding the vibrator module 16 with the fingers of the other hand, and pulling the main body 26 and the module 16 apart, the vibrator module 16 can be easily connected to the main body. 26 is separated, as shown in Figure 11.

When a new vibrator module needs to be installed on the scraper 10, first rotate the vibrator module 16 relative to the main body 26 until the corners of the hexagonal locking structure 128 are respectively embedded in the notches 126, so that The module is positioned at an angle, and then the module 16 is partially pressed into the main body 26. It can be seen from FIG. 11 that, since the locking structure 128 has a hexagonal cross-section, the vibrator module 16 can be easily assembled to the main body 26 by only rotating a relative angle of 60 degrees at most.

Then, screw the front cover 22 to the main body 26, and use a wrench to screw the scraping head 18 to the vibrator module 16. In the process of tightening the scraping head 18, the torque applied by the wrench will be borne by the main body 26, so the front cover 22 will not be affected by the tightening torque applied by the wrench. This advantageously prevents the front cover 22 from being over-tightened. Therefore, the front cover 22 can be easily released by hand when needed.

Figures 12-15 show a dental curette according to a fourth embodiment of the present invention. Those parts that are the same as those in the previous embodiment are denoted by the same reference numerals, and the description will not be repeated. The vibrator module 16 in this embodiment is the same as the module used in the embodiment shown in FIGS. 9-11.

This embodiment is characterized in that, compared with the third embodiment, the front cover is made significantly longer and slightly thinner. For this reason, the structure is made such that the vibrator module 16 is locked to the positioning sleeve during rotation.

More specifically, referring to FIGS. 12-15, the axial length of the front cover 22A is greater than half of the entire axial length of the handpiece 10. The main body 26A of the housing is shortened accordingly. Therefore, the contact point between the main body 26A and the front cover 22A is significantly located behind the front end of the positioning sleeve 90A.

The handpiece 10 has a conventional valve device 130 at its rear for controlling the flow of compressed air delivered to the vibrator module 16, and another conventional valve device 132 for controlling the delivery to the scraping head 18. The flow of cooling and cleaning water. The valve devices 130 and 132 are provided to allow the user to adjust the power of the vibrator and the flow rate of cooling water as needed. However, these valve devices are not necessary. Since these valve devices 130 and 132 are conventional and do not form part of the present invention, there is no need to show and describe their details.

The positioning sleeve 90A is integrally connected to the tubular housing 134, which defines a cavity 91, forming a part of the cavity 92 for accommodating the vibrator module 16. As shown in the figure, the housing 134 has a plurality of axially extending recesses or depressions 136 which are spaced apart from each other in the circumferential direction. These recesses 136 are designed to cooperate with the corresponding corners of the hexagonal structure 128 of the vibrator module 16 to lock the module 16 relative to the positioning sleeve 90A in rotation.

In order to prevent rotation and lock the vibrator module, a positioning sleeve 90A is used, which can make the front cover 22A longer, so that the threaded joint 20/ of the foregoing embodiment is removed in the area of the handpiece directly outside the vibrator module 16 in the radial direction. 24 and 120/122. This allows the outer diameter of the front cover at the position where the user's fingers are pinched during dental treatment to be reduced as much as possible. Although the possible reduction in the outer diameter of the front cover is as small as about less than 1 mm, this can significantly facilitate the user to hold the handpiece snugly and accurately position the dental tool relative to the teeth during treatment.

In this embodiment, the front cover 22A and the main body 26A are detachably connected to each other through a quick connection structure instead of the threaded joint 120/122 used in the third embodiment. In this way, as shown in FIG. 15, a telescopic locking pin 138 is slidably installed in a radial hole 140 formed in a connecting insert 142, and the connecting insert is tightly embedded in the housing main body 26A. The lock pin 138 is biased radially outward by a coil spring 144 so as to engage with a through hole 146 formed in the front cover 22A.

In use, the front cover 22A and the main body 26A are connected to each other by the lock pins 138 engaged in the corresponding holes 146. Since the vibrator module 16 is locked to the positioning sleeve 90A in rotation by the anti-rotation structure 128/134/136, a wrench is used to screw the scraper head 18 to and from the vibrator module 16 The torque applied to the scraping head will first be transmitted to the positioning sleeve 90A, and from there to the front cover 22A through the lock pin 138. Since the front cover is made long enough to be easy to hold, the torque applied by the wrench will be completely borne by the grip of the front cover 22A firmly.

In order to replace the vibrator module 16, first remove the scraping head 18 from the vibrator module 16, and push the lock pin 138 inward to escape the hole 146. When the front cover 22A is separated from the main body 26A, the vibrator module 16 will remain connected to the housing 134, as shown in FIG. 13. Obviously, it is now easy to hold the module 16 with your fingers and replace it with a new one, as shown in FIG. 14.

In the process of daily use of the handpiece, it is best to remove the front cover 22A from the handpiece and only sterilize the front cover with an autoclave and clean it with an ultrasonic cleaning device. Since the front cover covers most of the length of the handpiece, it is only necessary to frequently disinfect and purify the front cover to keep the handpiece basically clean and hygienic. Sterilizing only the front cover helps prevent thermal degradation of the vibrator module and other parts of the handpiece, thus prolonging the service life of these components.

Figures 16 and 17 show other embodiments of the present invention. Likewise, components similar to those in the previous embodiment are denoted by the same reference numerals.

In the embodiment shown in FIG. 16, the front cover 22A and the main body 26B forming part of the housing are detachably connected to each other by a threaded joint 148 and locked to each other by a locking screw 150. The locking screw 150 can advantageously prevent the front cover 22A and the main body 26B from undesirably loosening when the high-pressure head is screwed onto the vibrator module 16.

In the embodiment shown in FIG. 17, the front cover 22B is made long enough to substantially cover the entire length of the handpiece, thereby facilitating sterilization and improving the grip of the hand, as described above. The front cover 22B can also be used to cover the adjustment screws 152 and 154 of the flow control valve for controlling the flow of compressed air and cooling water installed in the main body 26B. Once the adjustment screws 152 and 154 are set and the lock pin 138 is used to connect the front cover 22B and the main body 26B to each other, the front cover 22B can prevent the adjustment screws 152 and 154 from being accidentally touched.

Although the present invention has been described with reference to its specific embodiments, the present invention is not limited thereto, and those skilled in the art can make various changes and modifications to it without departing from the scope of the present invention. For example, the pneumatic dental appliance of the present invention can be used in any occasion other than a dental curette. The structure, form and quantity of the elements constituting the anti-rotation mechanism can be changed. Specifically, the hexagonal structure can be changed to a triangular, quadrilateral or pentagonal structure, or replaced by one or more pins.