HK1131325B - Dental grinding bar and process for manufacturing the same - Google Patents

Description

Dental grinding rod and method for manufacturing same

Technical Field

The present invention relates to a dental grinding bar used for grinding teeth in dental treatment, and more particularly to a mark for identifying the type of the dental grinding bar.

Background

A dental grinding bar used for grinding teeth and the like has a stem portion formed at one base end portion of a rod-shaped base body for being held by a chuck such as an air motor, and a grinding portion formed at the other tip end portion thereof for fixing an abrasive. In order to fix the abrasive grains to the grinding portion of the dental grinding bar, a plating method is generally used.

This method is described in, for example, patent document 1 (japanese patent No. 3140517), and is performed as follows. First, a plating solution is filled in a plating tank, a refractory container containing abrasive grains to be fixed to a grinding portion is immersed in the plating solution, and an anode metal such as nickel is immersed in a position apart from the container. The abrasives in the container are immersed in the plating solution. Further, when a part of the base body serving as a grinding portion is inserted into the container and current is applied to the base body serving as a cathode, an anodic metal such as nickel is deposited on the surface of the grinding portion, and an abrasive in contact with the surface of the grinding portion is electrodeposited as the metal increases.

The dental grinding rods are different depending on the kind and particle size of the abrasive, and it is necessary to identify them, but generally, the identification is performed by forming an identification portion coated with a colored paint on a base and by the difference in color of the identification portion. Further, as a method for forming the identification portion, a groove is formed in the middle of the substrate, and a coating material is applied to the groove.

However, this method has the following problems. First, there is a problem in that the number of processes increases. When the abrasive is fixed to the grinding portion, in order to prevent the abrasive from adhering to the portion other than the grinding portion and to make the grinding portion end quite beautiful, the grinding portion is covered with an insulating tape, and the rear end of the base is entirely masked by a dipping method from the middle of the covering portion, so that only the grinding portion is fixed with abrasive grains. That is, a process of winding the insulating tape and a stripping process are additionally required.

Secondly, since the grooves are formed in the substrate, there is a problem that the strength of the substrate is lowered. Third, the dental grinding bar is used by being attached to a chuck such as an air motor, but there is a problem that the identification portion is not visible when the dental grinding bar is used, and the type of the dental grinding bar cannot be confirmed.

In order to solve these problems, patent document 2 (Japanese examined patent publication No. Hei 3-62089) proposes a method in which an insulating coating is applied to form a recognition portion without forming a groove in a substrate at a position adjacent to a grinding portion, and thereafter an abrasive is fixed.

That is, by applying the insulating coating material, the insulating tape can be coated at the same time, and the number of steps can be reduced. Further, since no groove is formed, a decrease in strength can be avoided. Further, by forming the identification portion at a position adjacent to the grinding portion, the identification portion can be visually confirmed even when the dental grinding bar is used.

Patent document 1: japanese patent No. 3140517

Patent document 2: japanese examined patent publication (Kokoku) No. 3-62089

However, the dental grinding bar in patent document 2 also has a need for improvement. That is, a thermosetting acrylic resin coating material and an ultraviolet curable resin coating material are used as the insulating coating material, but these coating materials have a problem of being easily peeled off. For example, there is a problem that the abrasive comes into contact with the identification portion to be peeled off when the abrasive is electrodeposited, or comes into contact with the affected part or with adjacent teeth to be peeled off at the time of treatment.

The best way to solve this problem is to form a groove and apply a coating thereto, however, there is a problem of a decrease in strength. In addition, the number of processing steps is also increased.

Disclosure of Invention

The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a dental grinding bar in which a groove for applying a paint is not required to be formed in a recognition portion, and the paint on the recognition portion is not easily removed.

In order to achieve the above object, a dental grinding bar according to the present invention includes: a rod-shaped base; a grinding part which is positioned at the front end part of the base body and is fixed with abrasive; and a recognition part which is located at the outer peripheral part of the base body adjacent to the grinding part and coated with insulating colored paint, wherein the recognition part has uniform thickness in the circumferential direction and is in a mountain shape in the axial direction, and the mountain shape is a mountain shape with a thicker central part and thinner two sides or a mountain shape with a top inclined to one side.

The abrasive is a diamond abrasive capable of being fixed to the grinding portion by electrodeposition.

In addition, a method for manufacturing a dental grinding bar according to the present invention includes the steps of: rotating the rod-shaped substrate at a speed at which a sufficient amount of the applied coating material is formed into a mountain-like shape (bulge shape) having a thick center in the axial direction by a centrifugal force; applying an insulating color paint to a portion having a predetermined width from a base end of the rotating base body as an operation portion by an application device; stopping the rotation of the substrate and drying the coating; and fixing the abrasive material to a portion located on the distal end side of the identification portion by electrodeposition.

The dental grinding bar manufacturing method can form the following structure: a step of drying the paint by stopping the rotation of the substrate, wherein the substrate is erected at a position where the substrate is removed from the rotating device; the coating device has an inclined surface contacting with the substrate, and supplies the coating to the contact part of the substrate from the upper part of the inclined surface in a mode of making the coating flow downwards; the coating material is sufficiently adhered to the coating device by surface tension, and the coating device is used to coat the coating material on the substrate so that the coating material is mountain-shaped in the axial direction.

Effects of the invention

After a sufficient amount of a colored paint is applied to a portion (about 1.4mm) having a predetermined width as an identification portion by bringing a coating device into contact with a substrate rotating at a speed of not less than a predetermined speed (about 100 to 1000 rpm), the paint is initially applied in a circular shape over the entire identification portion by applying surface tension. Thereafter, the coating apparatus is separated from the substrate, and the substrate is further rotated, so that the coating material is drawn outward by the centrifugal force. The centrifugal force concentrates the paint in the central portion of the identification portion and distributes the paint in a mountain shape having a thick central portion and thin both sides. When the substrate is rotated further, the paint becomes semi-dry. The mountain shape can be maintained even if the rotation is stopped after the semi-drying, so that the drying is performed while being left as it is. When the substrate is dried while standing upright, the coating material does not deflect to one side in the circumferential direction, and the thickness in the circumferential direction can be kept uniform. In this case, the mountain shape is slightly deviated in the gravity direction, but the mountain shape is deviated to one side, and the mountain shape is included in the "mountain shape" of the present invention. When the base is erected, the grinding part is usually erected upward, but the grinding part may be erected downward in a hanging manner. In this case, since the mountain shape is formed at a portion near the grinding portion due to the gravity, the abrasive can be prevented from being erroneously electrodeposited on the lower portion of the base. Further, since the paint is stretched outward by a centrifugal force, the paint needs to have a certain viscosity, and therefore the paint is used by appropriately adjusting the viscosity.

Since the coating film of the identification portion formed in this way is thick, the coating is less likely to fall off, and the usability is remarkably improved.

The coating device has an inclined surface contacting with the substrate, and supplies the coating material to the contact part of the substrate from the upper part of the inclined surface in a mode of making the coating material flow downwards, thereby being capable of sufficiently supplying the coating material, and preventing poor coating caused by cut-off of the coating material. The coating material is sufficiently adhered to the coating device by the surface tension, and the coating material can be applied to the substrate by the coating device so that the coating material is formed into a mountain shape in the axial direction, and the dental grinding bar of the present invention can be formed even at a speed (for example, 10prm or the like) at which the coating material becomes a mountain shape having a thick center in the axial direction due to a centrifugal force.

Drawings

Fig. 1 is a view for explaining a method of forming a dental grinding bar according to the present invention, fig. 1(a) is a front view of a base, fig. 1(b) is a front view of a state where a coating material is applied to the base, fig. 1(c) is a view showing a mask portion by a broken line in a state where a recognition portion is formed, fig. 1(d) is a front view of a finished dental grinding bar according to the present invention, and fig. 1(e) is a longitudinal sectional view of the dental grinding bar according to the present invention.

Fig. 2 is a diagram showing a configuration of a main part of the coating apparatus, fig. 2(a) is a plan view, and fig. 2(b) is a front view.

Description of the reference symbols

10: a dental grinding bar;

11: a substrate;

11 a: an identification unit;

20: a coating device;

21: a rotating device;

21 a: a chuck;

22: a coating device;

22 a: an inclined surface;

23: a drive device;

23 a: a rotating shaft;

30: a container;

a: an insulating colored coating.

Detailed Description

Embodiments of the present invention will be described below with reference to the drawings.

Fig. 1 is a view for explaining a method of forming a dental grinding bar according to the present invention, fig. 1(a) is a front view of a base, fig. 1(b) is a front view of a state where a coating material is applied to the base, fig. 1(c) is a view showing a mask portion by a broken line in a state where a recognition portion is formed, fig. 1(d) is a front view of a finished dental grinding bar according to the present invention, and fig. 1(e) is a longitudinal sectional view of the dental grinding bar according to the present invention.

The base 11 of the dental grinding bar 10 of the present invention is made of stainless steel since it is hard to rust. The front end of the stainless steel round bar is tapered and cut to a predetermined size to form the base 11. as the stainless steel, either martensitic stainless steel or austenitic stainless steel may be used.

Fig. 2 is a diagram showing a configuration of a main part of the coating apparatus 20, fig. 2(a) is a plan view, and fig. 2(b) is a front view. The coating device 20 includes a rotating device 21 and a coating device 22. The coating device 22 is a plate-like member, and is fixed to the rotary shaft 23a of the driving device 23 by a nut, and can be rotated by 90 ° in two directions, so that one position is selected from the position shown by the broken line and the position shown by the solid line in fig. 2 (b).

The substrate 11 shown in fig. 1(a) is clamped by a chuck 21a of a rotating device 21, and the substrate 11 is rotated. A container 30 containing an insulating color paint a is placed below the chuck 21a of the rotating device 21, and when the coating device 22 is positioned as indicated by the broken line, the tip of the coating device 22 is immersed in the color paint a, and the color paint a is adhered thereto. The front end of the coating device 22 has an inclined surface 22a, and when the device is rotated 90 ° counterclockwise from the broken line position to the solid line position, the lower side of the inclined surface 22a contacts the substrate 11, and the color paint a is coated on the substrate 11. The color paint a can be applied to a portion of the substrate 11a, which is the recognition portion 11a, by fixing the length of the substrate 11 and setting the position where the chuck 21a clamps the substrate 11 at a fixed position.

Since the paint flows down from above to below on the inclined surface 22a of the coating device 22, the color paint a can be applied to the outer periphery of the substrate 11 at a uniform thickness by continuously supplying a sufficient amount of paint to the contact portion between the substrate 11 and the coating device 22.

After the coating is applied, the coating device 22 is moved to the dotted line position by rotating it 90 ° clockwise. On the other hand, the substrate 11 continues to rotate. By continuing the rotation, the paint spreads to a uniform thickness toward the outer periphery, and expands outward due to the centrifugal force applied to the paint. The most easily expandable portion is the central portion of the identification portion 11a, and as shown in fig. 1(b), the paint is concentrated from both sides of the identification portion 11a toward the center and distributed in a mountain shape. In addition, as rotation continues, the paint also begins to dry. Further, when the paint is in the semi-dry state, the mountain distribution of the paint can be maintained even if the rotation is stopped.

After this state, the rotation device 21 is stopped, the substrate 11 is detached by loosening the chuck 21a, and the substrate 11 is held in an upright state at a position not shown, so that the paint is completely dried. After the paint is dried, the substrate 11 is held in the state shown by the solid line in fig. 1 (c). When the substrate 11 is dried while standing upright, the paint may slightly hang down if the previous dried state is insufficient. In this case, the thickness of the dried paint is not a laterally symmetrical mountain shape, but a shape in which the top of the mountain is offset downward.

Next, as shown by a dotted line in fig. 1(c), the entire lower portion of the base 11 is covered with a masking 12 from the middle of the recognized part 11a, and the base is put into a plating bath to electrodeposit abrasive grains to form a grinding part 11b, and then the masking 12 is peeled off to form the dental grinding bar 10 in fig. 1 (d). As shown in fig. 1(e), the cross-section of the dental grinding bar 10 is particularly a cross-sectional shape in which the recognizable portion 11a has a mountain shape in the axial direction (the longitudinal direction of the base 11).

The thickness of the coating was 28 μm at the portion of the measurement recognition portion 11a located 0.45mm from the side end of the grinding portion 11b, 34 μm at the center, and 34 μm at the portion located 0.45mm from the lower side of the substrate 11. The thickness of the coating film is at most 20 μm or more, preferably 30 μm or more, for preventing the coating from falling off, but can be selected appropriately according to the type of the coating. The upper limit of the thickness of the coating film is a thickness at which the coating can be applied in general, but is not particularly limited.

The viscosity of the coating material is preferably about 15 to 30 seconds (measured as NK-2), but the value is not limited thereto.

Since the identification portion 11a of the present invention is located close to the grinding portion 11b, the color of the identification portion 11a can be checked even when the device is mounted on a rotary device for use. Further, since no grooving is required, the rigidity of the grinding rod is not weakened.

In particular, since the substrate 11 is rotated, the insulating colored paint a is applied thereto, and the rotation is continued after the application, the thickness of the coating film of the identification portion 11a of the present invention in the circumferential direction is uniform. Further, since the thickness in the axial direction is mountain-shaped, the identification portion 11a is thick and is not easily detached.

Claims (6)

1. A dental grinding bar is characterized in that,

the dental grinding bar includes: a rod-shaped base; a grinding part which is positioned at the front end part of the base body and is fixed with abrasive; and a recognition part which is located at the outer peripheral part of the base body adjacent to the grinding part and coated with insulating colored paint, wherein the recognition part has uniform thickness in the circumferential direction and is in a mountain shape in the axial direction, and the mountain shape is a mountain shape with a thicker central part and thinner two sides or a mountain shape with a top inclined to one side.

2. A dental grinding bar as in claim 1,

the grinding material is a diamond grinding material which can be fixed on the grinding part through electrodeposition.

3. A method for manufacturing a dental grinding bar,

the method for manufacturing the dental grinding rod comprises the following steps:

rotating the rod-like substrate at a speed at which a sufficient amount of the applied coating material becomes a mountain-like shape with a thick center in the axial direction due to centrifugal force;

applying an insulating color paint to a portion having a predetermined width from a base end of the rotating base body as an operation portion by an application device;

stopping the rotation of the substrate and drying the coating; and

and fixing the abrasive material to a portion located on the front end side of the identification portion by electrodeposition.

4. The method of manufacturing a dental grinding bar as set forth in claim 3,

the step of drying the paint by stopping the rotation of the substrate is performed by raising the substrate at a position after the substrate is removed from the rotating device.

5. The method of manufacturing a dental grinding bar as set forth in claim 3 or 4,

the coating device has an inclined surface that contacts the substrate, and supplies the coating material to the contact portion of the substrate from above the inclined surface so that the coating material flows down.

6. The method of manufacturing a dental grinding bar as set forth in claim 3 or 4,

the coating material is sufficiently adhered to the coating device by surface tension, and the coating device is used to coat the coating material on the substrate so that the coating material is mountain-shaped in the axial direction.