JPH084599B2 - Handpiece - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a handpiece as a dental medical instrument.

[0002]

2. Description of the Related Art In a conventional handpiece, a handle portion and a handle tip portion to which a rotary drive unit can be attached are integrated by welding or screwing, and the rotary drive unit is inserted into a casing of the handle tip portion and then a cap is used. It is generally used by screwing, fixing and integrating.

[0003]

In the field of dentistry, the risk of secondary infections such as AIDS and hepatitis is extremely high due to the handpiece among many therapeutic instruments. ing.

The reason is that instruments such as pliers and tweezers can be sterilized or sterilized with little trouble in boiling water liquid or in a high temperature sterilization furnace and can be used repeatedly, but the internal structure of conventional handpieces is small. It requires high speed rotation and is composed of precision parts including bearings. Therefore, after repeated high temperature sterilization, it is necessary to replenish the bearing with lubricating oil, but the lubrication state cannot be confirmed.

Further, since a complete seal is not possible due to the internal structure, it cannot be washed to remove the residue after sterilization unless the unit containing the rotating mechanism such as the turbine and the bearing is removed.

An object of the present invention is to fundamentally solve these problems and provide a handpiece capable of protecting secondary infections in dental care such as AIDS and hepatitis.

[0007]

According to the present invention, in order to achieve the above-mentioned object, a cartridge (3) containing a rotary drive portion of a bar (21) is made of a plastic molded product except for bearings. , The handle (1) and the cartridge (3) are separate parts that can be attached to and detached from each other, and the tip portion (2) of the handle (1) is fitted into the casing (4) that constitutes this cartridge (3). A tubular portion (4a) is provided, and from the top surface of the head of the casing (4), the bearing (12), the flange (26), the bearing (12 '), and the pressure retainer (27) are attached to the turbine rotating shaft (11). The turbine assembly assembled in order is inserted to form the rotary drive part, but the inner circumference of the upper surface of the head of the casing (4) has a taper fitting part (28), and the side surface is tapered (28 ') to be snap-fastened. Caps (16) A polygonal surface (14 ') is formed below the tapered fitting portion (28) and the pressurizing retainer (27) has an outer peripheral cylindrical shape of a polygonal surface (14). ′) Has a small clearance that allows the polygonal surface (14) to slide up and down, and the pressurizing retainer (27) has an inner circumference molded to a size that allows the outer ring of the bearing (12 ′) to be press-fitted. Outer ring holder (13)
And the outer ring of this bearing (12 ') is pushed down with an appropriate pressure, and the spring-like elasticity causes the whole to move up and down against a fluctuating load, always keeping the axial gap between the bearing (12) and the bearing (12') constant. The turbine inner shaft of the turbine rotating shaft (11) is provided with an elastic imparting part (15) that can maintain the straightness of the bar (20) and the diameter of the bar (21) is smaller than that of the bar (21). The gist of the present invention is that the stop cylindrical portion (18) for preventing the through protrusion of (21) and the tapered cylindrical portion (19) in the middle thereof are provided.

[0008]

According to the present invention, the handle (1) and the cartridge (3) are separate parts, and the purpose of use of the handpiece is achieved by docking and integrating them with one touch each time of use. Due to the separation of the two parts, the handle (1) withstands repeated high temperature sterilization to protect against secondary infections such as AIDS and hepatitis, which are rapidly increasing.
It enables complete sterilization and high-temperature washing for residue removal.

A cartridge (3) having a built-in rotation driving unit which can be attached / detached to / from the handle end (2) with one touch.
Can be made disposable to ensure hygiene and safety.

The elasticity imparting portion (15), which is the upper surface plate of the pressurizing retainer (27), has a wave-shaped elastic curved surface during assembly by the end surface of the rib-shaped ring (17) contacting the end surface of the cap (16). When it occurs, the outer ring of the bearing (12 ') is pushed down by an appropriate pressure, and the spring-like elasticity causes the pressure retainer (27) to move up and down as a whole, and the bearing (12) and the bearing (12') always move. It is possible to properly maintain the axial clearance of.

The inner diameter cylindrical structure of the turbine rotating shaft (11) is
Since the straight cylindrical part (20), the stop part (18) and the tapered cylindrical part (19) in the middle of the straight cylindrical part (20) are provided, the straight cylindrical part (20) maintains the bar straight holding accuracy and the tapered cylindrical part. In (19), due to plastic plastic elasticity, the bar (21) is securely chucked even when the turbine rotates at high speed.
In addition, even if the shaft diameter tolerance of the bar (21) is slight, vibration due to center deviation does not occur, and the bar (21) is loose.
Prevent falling accidents.

[0012]

Embodiments of the present invention will now be described in detail with reference to the drawings. 1 is a side view before docking showing one embodiment of a handpiece of the present invention, FIG. 2 is a plan view of the same as above, and FIG. 5 is a side view after docking.

The handle (1) and the cartridge (3) are separate parts, of which the handle (1) is a simple pipe-shaped structure made of metal or high heat resistant resin that is free from alteration, deformation and corrosion. In a high-temperature liquid such as boiling water or in a high-temperature sterilization furnace, complete sterilization and washing can be performed without the risk of failure of the rotary drive unit.

The handle tip portion (2) of the handle (1) is an angled portion of the body of the handle (1).

Then, as shown in FIG. 4, the handle (1)
On the rear end face, a turbine rotation air supply pipe (32), a water pipe (33) for mixed spraying of air and water, an air pipe (34) and an exhaust pipe (35) are provided, which is used as an operating table for dental treatment. Compressed air and water are supplied by the connecting tube connector, and the air supply pipe (32), the water pipe (33) and the air pipe are attached to the front end surface of the handle (1) as shown in FIG. Each (34) protrudes into place.

On the other hand, in order to make the cartridge (3) disposable and inexpensive, all parts except the bearings (12) and (12 ') are made of plastic molded products.

As shown in FIGS. 6 and 8, the casing (4) constituting the cartridge (3) has a tubular portion (4a) into which the handle tip (2) is fitted, with its opening at the rear end. A concave ring groove (5) is provided on the inner peripheral surface of the cylindrical portion (4a) near the rear end of the tubular portion (4a) so as to prevent it from coming off when it is integrally docked with the handle (1). .

On the other hand, the handle (1) has
In order to integrate docking, a mountain-shaped ring (6) protruding in accordance with the position of the concave ring groove (5) formed on the inner peripheral surface of the casing (4) is provided on the rear end of the handle front end (2). The handle (1) and the cartridge (3) are pressed together in the directions (7) and (7 ') of the arrow so that they can be docked and integrated with one touch.

When the handle (1) and the cartridge (3) are separated, they can be separated with one touch by pulling the arrow directions (8) and (8 ').

An R-concave key groove (9) is provided in front of the mountain-shaped ring (6) of the handle (1), and is provided on the inner peripheral surface of the tubular portion (4a) of the casing (4). Is provided with an R-shaped key (10) protruding in the vertical direction, and the key (10) is engaged with the key groove (9) to prevent the cartridge (3) from rotating during docking.

As shown in FIG. 10, from the top surface of the head of the casing (4) of the cartridge (3), the turbine rotating shaft (11)
Then, the turbine assembly assembled in the order of the bearing (12), the flange (26), the bearing (12 ') and the pressurizing retainer (27) was inserted into the rotary drive part.

The bearings (12) and (12 ') have a function of causing the outer ring to rotate in the rotation direction due to inertia at the time of starting rotation, so that the outer ring is fixed to smooth the rolling of the bearing balls. I need.

Further, the bearings (12) and (12 ') are built in the turbine rotating shaft (11) above and below with the central turbine blade sandwiched between them, but they are molded on the inner and outer rings of the rolling surface of the bearing ball. Because of the R groove, there is an axial gap, which causes looseness of the inner and outer rings in the thrust direction. This axial gap is spring-like elasticity so that the tip of the bar (21) can always be kept constant according to changes in radial and axial loads during cutting, and is suitable for the inner and outer rings of the bearings (12) (12 '). It is necessary to apply pressure.

Further, as described above, in order to sufficiently exert the bearing performance, the variable loads in the thrust direction and the radial direction generated during the cutting work of the bar (21) are absorbed,
It is necessary to prevent the outer ring from rotating due to inertia as well as to rotate smoothly with a constant pressure.

A cap (16) for accommodating the turbine assembly in a fixed position is fitted on the upper surface of the head of the casing (4).
The inner circumference of the upper surface of the head of the casing (4) is tapered (2
8) and the side surface of the cap (16) is a taper (28 ') that engages with the taper fitting portion (28).

A casing tip head portion (29) for heating car rig fusion is secured above the tapered fitting portion (28) of the casing (4), and a polygon is provided below the tapered fitting portion (28). Mold the surface (14 ').

The outer peripheral cylindrical shape of the pressurizing retainer (27) is a polygonal surface (14), and the polygonal surface (14 ') at a position opposite to the inner cylinder pressurizing retainer (27) of the casing (4).
Has a small clearance that allows the polygonal surface (14) to slide up and down.

As shown in FIG. 11, this pressurizing retainer (2
The outer ring holding part (13) of the inner circumference of 7) is a bearing (12 ')
The outer ring of the bearing is molded into a size that can be press-fitted and the bearing (12 ')
Secure the outer ring of. Further, in order to keep the axial gap between the bearing (12) and the bearing (12 ') appropriate, the elastic imparting portion (15) which is the upper surface plate of the pressurizing retainer (27) has a rib shape that contacts the end surface of the cap (16). The end surface of the ring (17) creates a wave-like elastic curved surface during assembly to push down the outer ring of the bearing (12 ') with an appropriate pressure, and the spring-like elasticity pressurizes the retainer (27) against fluctuating load.
As a result, the whole system operates up and down so that the axial clearance can always be kept constant.

By the way, in the cutting work with the handpiece, the bar (21) is surely chucked when the turbine rotates at a high speed, and the vibration due to the center deviation is caused by the slight variation in the shaft diameter tolerance of the bar (21). You need to ensure chucking without getting up.

Therefore, the inner diameter cylindrical structure of the turbine rotating shaft (11) is assumed to be composed of a straight cylindrical portion (20), a stop portion (18), and a tapered cylindrical portion (19) in the middle thereof.

The straight cylindrical part (20) maintains the straightness holding accuracy of the bar, and the tapered cylindrical part (19) completely secures the chucking of the bar (21) by plastic plastic elasticity.
Prevents the bar (21) from loosening and falling off even when the turbine rotates at high speed.

The stop cylinder part (18) is a cylinder having a diameter smaller than that of the bar (21) so that the bar (21) can be stopped at a fixed position when the bar (21) is inserted to prevent the bar (21) from projecting through.

Next, usage and operation will be described. When reaching the end of the handpiece, move the tip (2) of the handle (1) and the cartridge (3) toward each other in the direction of the arrow (7).
Docking integrated with (7 ').

A mountain-shaped protruding ring (6) and an R-shaped keyway (9) are provided on the handle tip (2) of the handle (1).
The concave ring groove (5) on the inner peripheral surface of the cylinder of the cartridge (3) and the protruding key (10) are fitted to each other to prevent the retainer and the detent.

The bar (21) firmly fixed by the straight cylindrical portion (20) and the tapered cylindrical portion (19) provided on the inner peripheral surface of the turbine rotating shaft (11) is provided with a turbine rotating air supply pipe (32). The air that is more pumped and accelerated by the compressed air injection hole (30) rotates in conjunction with the high-speed rotation of the turbine.

The heat generated when the high-speed rotating bar (21) is applied to the dental affected area for cutting is generated by the water pipe (33) and the air pipe.
Pass through (34) through casing of cartridge (3) (14)
It reaches the spray holes provided in each of them, and the mixture injection holes (36) are formed in a slanting manner to form a spray and cool the bar (21) and the affected area.

Depending on the condition of the affected area, the turbine rotating shaft (11)
The fluctuating load is applied in the radial direction and the thrust direction to the bar (21) fixed to the turbine (21), and the same fluctuating load is also applied to the turbine rotating shaft (11).

The bearings (12) and (12 ') always require stable rotation of the bearing balls against the above-mentioned fluctuating load, but in order to rotate the radial load and the thrust load with respect to the torque within the allowable range without difficulty. The bearing (1
2) The axial clearance of (12 ') must be maintained by constant pressure.

The pressurizing retainer (27) performs the following functions in order to maintain the axial clearance of the bearing by a constant pressurization. Due to the polygonal surface (14) on the outer periphery, the polygonal surface (14 ') facing the casing (4) moves up and down with a small clearance that can slide, against overload at the start of rotation and cutting. In addition, rotation of the outer ring of the bearing (12 ') due to inertia is prevented. Elasticity imparting part (15)
Keeps a constant pressure on the bearing by spring-like elasticity through a ring (17) that contacts the inner end surface of the cap (16) with a film-like ring. The outer ring holding portion (13) fixes the outer ring by the inner cylinder peripheral surface that can always provide an appropriate pressure of a slip detent that can prevent the outer ring slip due to inertia during rotation of the bearing (12 ').

Due to the three functions of the pressurizing retainer (27), the turbine rotating shaft (11) and the bar (21) can smoothly keep rotating with respect to the torque within the allowable range.

A turbine blade is formed on the outer periphery of the turbine rotating shaft (11), and a flange is integrally formed on one side of the turbine rotating shaft (11) in order to prevent expansion of the tip of the turbine blade due to centrifugal force due to high speed rotation.

By inserting a flange (26) into one of them, both end faces are closed to form bucket-shaped turbine blades, and the energy of the injection air can be converted to the maximum rotational energy.

The bar (21) is vertically held by the straight cylindrical portion (20) and the tapered cylindrical portion (19) of the inner cylindrical surface of the turbine rotating shaft (11) and firmly held by the elastic chucking torque. Rotate. The rear end of the bar (21) stops in place without a through protrusion by a stop cylinder (18) with a diameter smaller than that of the bar (21).

In the manufacturing process of the handpiece of the present invention, as described above, the tapered fitting portion (28) between the casing head of the cartridge (3) and the cap (16) is
The turbine assembly assembled in the order of the bearing (12), the flange (26), the bearing (12 ') and the pressurizing retainer (27) was inserted into the turbine rotating shaft (11) from the upper surface of the head of the casing (4). After that, the cap (16) is fitted and mounted, and a confirmation inspection for normal rotation is performed.

After the confirmation, the head end (29) of the casing tip is fusion-bonded with a heating car rig to complete the assembly.

In this inspection process, if a defective rotation is generated, in order to re-inspect whether or not it is based on the assembly procedure of the parts having the specified dimensions, the cap ( 16) Remove and take out the turbine assembly.

Cartridge (3) for conducting inspection work
Compressed air is sent from the compressed air injection hole (30a) to check the rotation, but the cap (16) is prevented from floating and fixed by the injection pressure of the compressed air even before the heating curling fusion, so that the cap is fixed. The side of the cap (16) is tapered (28
′) And the taper fitting part (28) of the casing (4) are engaged by snap-fitting and inspection.

After confirming that the operation is normal, the casing head portion (29) is heated and curling-fused to be integrated.

When the affected part is to be deleted by hand bead, appropriate removal treatment is performed by exchanging several kinds of bars (21) having different tip shapes depending on the condition of the affected part.

The bar (21) can be quickly detached from the cartridge (3), and the replaced bar (21) needs to be securely chucked even if there is a diameter difference within the dimensional tolerance range. . For reliable chucking and attachment / detachment work of the bar (21), since the bar (21) is firmly chucked by the plastic plastic elasticity of the tapered cylindrical portion (19), the insertion work and the removal work of the bar (21) are performed. A large amount of torque is required for the work, and the bearings must be attached and detached without damage to the bearing due to excessive load during the insertion and extraction work.

Therefore, the present invention uses an attaching / detaching jig (31) as shown in FIG. The attaching / detaching jig (31) is
A two-divided cavity having the same shape as the head of the cartridge (3) and having the same shape can be freely opened and closed by a hinge. The vertical direction of the cavity of the attaching / detaching jig (31) is the same as the length of the turbine rotating shaft (11) built in the cartridge (3).

The attachment / detachment jig (31) has the same cylindrical diameter as the bar (21) when the attachment / detachment jig is closed by the right and left symmetrical R-shaped portions of the attachment / detachment jig. When the bar is pressed, the insertion guide part (25), which is a part that linearly slides, and the left and right symmetrical R-shapes of the detachable jig that can be opened and closed like this insertion guide part (25). When the left and right sides of the attachment / detachment jig are closed, the push-out guide part (37) is provided as a part which has the same cylindrical diameter as the stop cylinder part (18) and which slides the pin (24) straightly.

Further, the attachment / detachment jig (31) includes a jig (2) for extracting the bar (21) integrally provided with the pin (24).
3) and the insertion jig (22) having a concave taper at the tip of the bar (21) are integrally molded, and they are arranged above and below the two-divided external shape of the cartridge (3).

In this way, when the head of the cartridge (3) is wrapped by closing the attachment / detachment jig (31) for molding the cavity into the left and right symmetrical shapes of vertical division, when the bar (21) is pressed and inserted, The tip of the bar (21) is applied to the insertion jig (22) having a concave taper at the tip, and the bar (21) is press-fitted from the insertion guide (25).

In the work of extracting the bar (21), the pin (24) of the extracting jig (23) is inserted into the pushing guide portion (37) and the stop cylinder portion (18) of the turbine shaft (11) and then pressed. The bar (21) firmly chucked in the tapered cylindrical portion (19) of the turbine rotating shaft (11) can be removed.

Due to the above structure and operation, the turbine shaft (11) and the bearings (12) and (12 ') are prevented from moving up and down by the attachment / detachment jig (31), and the roller R surface of the bearing and the bearing ball are overloaded. It is possible to repeat the work of attaching and detaching the bar (21) without damaging it. Further, due to the sliding effect of the insertion guide portion (25) and the push-out guide portion (37) of the bar (21), it is possible to prevent bending deformation of the bar (21) and damage of the tip cutting edge due to the attachment / detachment work.

[0057]

As described above, in the handpiece of the present invention, the handle and the cartridge are separate parts, and the purpose of use of the handpiece is achieved by docking and integrating them with each other with one touch each time of use. so,
By separating the two parts, the handle withstands repeated high temperature sterilization, complete sterilization and high temperature washing to remove residues, and Cartridge secures hygiene and safety by making it disposable. Therefore, it is possible to protect against secondary infection in dental care such as AIDS and hepatitis.

Axial clearance of the bearing is maintained by a constant pressure, so that stable rotation of the bearing ball can always be secured against fluctuating load, and the bar is surely chucked even at high speed rotation of the turbine, and a slight amount of fluctuation is caused. Vibration due to center deviation does not occur against the deviation of the shaft diameter tolerance of the bar, and it is possible to prevent loosening and falling accidents of the bar.

[Brief description of drawings]

FIG. 1 is a side view of a handpiece according to an embodiment of the present invention before docking.

FIG. 2 is a plan view showing an embodiment of the handpiece of the present invention before docking.

FIG. 3 is a front end view of the handle.

FIG. 4 is a rear end surface of a handle.

FIG. 5 is a side view after docking showing an embodiment of the handpiece of the present invention.

FIG. 6 is a vertical side view of the cartridge.

FIG. 7 is a sectional view taken along line AA of FIG. 6;

FIG. 8 is a cross-sectional plan view of the cartridge.

9 is a cross-sectional view taken along the line BB of FIG.

FIG. 10 is an exploded perspective view of a cartridge.

FIG. 11 is a partially cutaway perspective view of the pressurizing retainer.

FIG. 12 is a perspective view of an attachment / detachment jig for a cartridge and a bar.

[Explanation of symbols]

(1) ... Handle (2) ... Handle tip (3) ... Cartridge (4) ... Casing (4a) ... Cylindrical part (5) ... Recessed ring groove (6) ... Mountain-shaped ring (7) ( 7 ')
(8) (8 ') ... arrow (9) ... key groove (10) ... key (11) ... turbine rotating shaft (12) (12')
... Bearing (13) ... Outer ring holding part (13 ') ... Bearing outer ring (14) (14') ... Polygonal surface (15) ... Elasticity providing part (16) ... Cap (17) ... Ring (18) ... Stop cylindrical part (19)… Tapered cylindrical part (20)… Straight cylindrical part (21)… Bar (22)… Insertion jig (23)… Extrusion jig (24)… Pin (25)… Insertion guide part (26)… Flange (27)… Pressurized retainer (28)… Taper fitting part (28 ′)… Taper (29)… Casing tip head part (30) (30a)
… Compressed air injection hole (31)… Detachment jig (32)… Air supply pipe (33)… Water pipe (34)… Air pipe (35)… Exhaust pipe (35 ′)… Exhaust hole (36)… Mixed injection Hole (37)… Extrusion guide

Claims (4)

[Claims] 1. A cartridge (3) having a built-in rotary drive part of a bar (21), wherein all parts except a bearing are made of plastic molding so that the handle (1) and the cartridge (3) are mutually connected. The casing (4) constituting the cartridge (3) is provided with a tubular portion (4a) into which the tip portion (2) of the handle (1) is fitted. From the top surface of the head, insert the turbine assembly assembled in the order of bearing (12), flange (26), bearing (12 ') and pressurizing retainer (27) into the turbine rotating shaft (11) to install the rotary drive unit. Although the inner periphery of the upper surface of the head of the casing (4) is formed as a tapered fitting portion (28), the side surface is tapered (28 ') and a snap-fittable cap (16) is fitted to the tapered fitting portion. Below (28) is a polygon (14 ' ), And the pressurizing retainer (27) has a polygonal surface (14) as the outer peripheral cylindrical shape, and the polygonal surface (14 ′) has a small clearance allowing the polygonal surface (14) to slide up and down. In addition, the pressurizing retainer (27) is molded into a size such that the outer ring of the bearing (12 ') can be press-fitted into the pressurizing retainer (27).
And the outer ring of this bearing (12 ') is pushed down with an appropriate pressure, and the spring-like elasticity causes the whole to move up and down against a fluctuating load, always keeping the axial gap between the bearing (12) and the bearing (12') constant. The turbine inner shaft of the turbine rotating shaft (11) is provided with an elastic imparting part (15) that can maintain the straightness of the bar (20) and the diameter of the bar (21) is smaller than that of the bar (21). A handpiece comprising a stop cylindrical portion (18) for preventing a through protrusion of (21) and a tapered cylindrical portion (19) in the middle thereof. 2. A cylindrical ring portion (4a) of the casing (4), which is formed by docking with the distal end portion (2) of the handle (1) and uses a plastic ring-like elastic groove to prevent the stopper from coming off. 5) is formed on the inner peripheral surface, while the concave ring groove (5) is formed on the tip portion (2) of the handle (1).
The handpiece according to claim 1, wherein a chevron-shaped ring (6) that engages with is formed on the outer peripheral surface. 3. The chevron-shaped ring (6) of the handle (1).
A key groove (9) having an R-shaped recess is provided in front of the casing, and an R-shaped key (10) protruding in the vertical direction is provided on the inner peripheral surface of the tubular portion (4a) of the casing (4). The handpiece according to claim 1 or claim 2. 4. The insertion guide part (25) and the push-out guide part (37) can be opened and closed by left and right cavities of two-part shape having the same shape as the head part of the cartridge (3) and having the same shape. (2) having a pin (24) integrally formed with a detaching jig (31) having a bar (21).
The handpiece according to any one of claims 1 to 3, wherein 3) is combined with an insertion jig (22) having a concave taper at the tip of the bar (21).