JPH0532108Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] This invention is used in dental applications to tighten and hold tools for cutting, grinding, polishing, etc. of teeth and dentures, and to give rotational motion to the tools. Concerning improvement of contra angle.

[Prior Art] FIG. 5 is a conceptual diagram showing a conventional contra-angle 1.

This contra-angle 1 is made up of a sheath 2 that is attached to the tip of a handpiece (not shown) and an elbow 3 that is bent at a predetermined angle and screwed to the sheath 2.
The dental treatment tool is made up of a neck 4 which screws onto the elbow 3, and a head 9 to which a dental treatment tool 8 such as a brush 5, drills 6, 7, etc. is detachably attached.

On the other hand, the power transmission path for transmitting rotational motion to the tool 8 attached to the above-mentioned head 9 is transmitted from a hand piece (not shown) as shown in FIG. At the bent portion 3a of the spindle 10 and elbow 3, which transmits the rotational force,
A first gear transmission means 12 for transmitting the rotational force to the transmission spindle 11 supported on the neck 4, and a first gear transmission means 12 for transmitting the rotational force to the transmission spindle 11, arranged horizontally in the head 9. and a second gear transmission means 14 for transmitting the signal to the final spindle 13.

The first gear transmission means 12 described above is composed of a gear 15 fixed to the upper end of the spindle 10, and a gear 16 meshed with the gear 15 and fixed to the lower end of the transmission spindle 11. The second gear transmission means 14 is composed of a gear 17 fixed to the upper end of the transmission spindle 11, and a gear 18 meshing with the gear 17 and fixed to the final spindle 13. There is.

According to the power transmission path described above, the spindle 1
0 rotates, its rotational force is transmitted to the final spindle 13 via the first gear transmission means 12, the transmission spindle 11, and the second gear transmission means 14.

On the other hand, a final spindle 13 disposed within the head 9 is equipped with a shaft portion 8a (FIGS. 6 and 5) of a tool 8 in a detachable manner, and is used to transmit rotational force to the tool 8. A hole 13a is formed at the rear end of the hole 13a, and a protrusion 13b that fits into a recess 8b (FIGS. 6 and 5) formed at the rear end of the tool 8 is formed. .

Therefore, according to the mounting structure of the final spindle 13 and the tool 8 described above, when the final spindle 13 rotates, the tool 8 rotates following the rotation.

Further, since it is not possible to prevent the tool 8 from coming off in the axial direction of the final spindle 13 with only the mounting structure of the final spindle 13 and the tool 8 described above, a screw 19 is installed at the rear of the head 9.
A plate-shaped bar latch 21 is rotatably supported around a shaft 20, and a notch 21a formed above is connected to the shaft portion 8 of the tool 8.
a Small diameter portion 8c formed at the rear end (Figs. 6 and 5)
(Fig.). The lower end 21b of the bar latch 21 has a V-shaped cross section, and by resiliently engaging the V-shaped rear end 21b with the circumferential surface of the neck 4,
Rotation of the bar latch 21 under normal conditions is restricted.

According to such a structure for preventing the tool 8 from falling out, when replacing the tool, rotate the bar latch 21 counterclockwise about the shaft 20 from the rotational position of the bar latch 21 in FIG. 7 shown in the right side view in FIG. When the bar latch 21 is rotated by a predetermined angle, the engagement between the notch 21a of the bar latch 21 and the small diameter portion 8c (FIG. 6) formed at the rear end of the shaft portion 8a of the tool 8 is released, as shown in FIG. Therefore, by pulling the tool 8 to the left in the drawing from the position shown in FIG. 6, the tool 8 can be taken out from the hole 13a of the final spindle 13 disposed in the head 9.

To install a new tool 8 into the head 9, insert the tool 8 into the hole 13a of the final spindle 13 in the reverse order of the above-mentioned operation, and then rotate the bar latch 21 as shown in FIG. If the bar latch 21 is rotated by a predetermined angle clockwise from the position, the bar latch 21
A notch 21a formed at the upper part of the small diameter part 8 is formed at the rear end of the shaft part 8a of the newly inserted tool 8.
c, and the tool 8 is immovably mounted within the head 9.

On the other hand, in the above-mentioned contra-angle 1,
As shown in the figure, in order to transmit the rotational force to each spindle whose position has been changed, a first
The gear transmission means 12 is disposed in the head 9, and the second gear transmission means 14 is disposed in the head 9.
In order to maintain the smooth operation of these gear transmission means, it is necessary to supply oil during maintenance and inspection. For this reason, as shown in Figure 6, a first oil supply hole 30 and a second oil supply hole 31 are formed in the bent portion 3a of the elbow 3 and the rear end of the head 9, respectively.

The first and second oil filling holes 3
As shown in FIG. 7, the first oil filling hole 31 formed in the head 9 of 0 and 31 is opened by the surface of the bar latch 21 in the rotational position where the tool 8 is prevented from coming out by the bar latch 21. When the tool 8 is closed and the locking of the tool 8 by the bar latch 21 is released as shown in FIG.
The oil filling hole 31 is unblocked and oil can be filled into the head 9 through the oil filling hole 31.

Note that, conventionally, the second oil filling hole 30 formed in the elbow 3 remains open at all times.

[The problem that the idea aims to solve]

By the way, the above-mentioned dental contra angle 1
According to the above, since the first oil lubrication hole 30 formed in the elbow 3 remains open at all times, the oil supplied into the elbow 3 is supplied to the second oil lubrication hole 30 when the first gear transmission means 12 is operated. There was a problem with the water flowing out from the hole 30.

Conversely, since the first oil fill hole 30 formed in the elbow 3 remains open at all times, dust and the like enter the inside of the elbow 3 through this second oil fill hole 30, and the first gear transmission There was also a risk that the particles would adhere to the means 12 and interfere with its smooth drive, making it impossible to maintain stable operation of the power transmission path.

Note that it is conceivable to close this first oil filling hole 30 with an independent plug member such as a screw,
In this case, there is a problem that the number of parts and manufacturing steps increases, which increases manufacturing costs.In addition, when performing lubrication work during maintenance and inspection, it is necessary to remove the plug member and reinstall it when finished. A certain difficulty arises.

In view of the above-mentioned circumstances, this dental contra angle does not require an increase in the number of parts, simplifies lubrication work during maintenance and inspection, maintains stable operation of the power transmission path, and prevents oil leakage. The purpose is to provide

[Means to solve the problem]

In order to achieve the above-mentioned object, this invention includes an elbow having a first gear transmission means therein and a first oil lubrication hole for supplying oil to the first gear transmission means; A head for mounting a tool, which is mounted above and has a second gear transmission means therein, and is formed with a second oil lubrication hole for supplying oil to the second gear transmission means; It is rotatably supported, and a notch at its upper end prevents the tool attached to the head from coming off, and its surface closes the second oil filling hole at the rotational position to prevent the tool from coming off. In the dental contra angle, the lower end of the bar latch extends at least to a position where the first oil fill hole is formed, and the extended end is attached to the head. A protrusion is formed that fits into the first oil fill hole at the rotational position where the tool is prevented from coming off.

[Effect]

According to the dental contra angle mentioned above,
At the rotational position where the bar latch prevents the tool from coming out, the second oil fill hole is blocked by the upper surface of the bar latch, and the protrusion formed at the lower end of the bar latch fits into the first oil fill hole. At the same time, the first oil filling hole is also blocked.

Moreover, the first and second oil filling holes can be simultaneously expanded by the simple operation of rotating the bar latch.

〔Example〕

An embodiment of the dental contra-angle according to this invention will be described in detail below.

FIG. 1 is a conceptual diagram of a dental contra-angle 40 according to this invention, and the same parts as in FIG. 5 are designated by the same symbols.

In this dental contra-angle 40, the lower end 41a of the bar latch 41, which prevents the tool 8 attached to the head 9 from being removed, is coated with the first oil as shown in FIG. The bar latch 41 extends to the position where the oil filling hole 30 is formed, and a protrusion 41b is formed on the back surface of the lower end 41a. 1 oil lubrication hole 30
The first oil filling hole 30 is closed.

Next, the action of the above-mentioned bar latch 41 will be explained,
The configuration will also be explained in more detail.

According to the structure of the bar latch 41 described above, the second
As shown in FIG. 3, which is a right side view of the figure, in the rotational position where the bar latch 41 prevents the tool 8 from being removed, the upper surface of the bar latch 41 causes the second
The oil filling hole 31 of the
The oil lubrication hole 30 (Fig. 2) is also closed by the protrusion 41b formed on the back surface of the lower end 41a of the extended bar latch 41. Therefore, the bar latch 41 prevents the tool 8 from coming out. In the desired rotational position, that is, in the normal rotational position of the bar latch 41 for rotationally driving the tool 8, both the first and second oil filling holes 30, 31 are connected to the bar latch 41.
Since the oil injected into the head 9 and the elbow 3 to lubricate the first and second gear transmission means 12 and 14 shown in FIG.
The oil does not flow out from the second oil filling holes 30 and 31, and no dust or the like enters into the elbow 3.

On the other hand, the tool 8 attached to the head 9 (Fig. 1)
or when injecting oil for maintenance and inspection of the first and second gear transmission means 12, 14, move the bar latch 41 counterclockwise around the shaft 20 shown in FIG. All you have to do is rotate it by a predetermined angle.

That is, when the bar latch 41 is rotated counterclockwise by a predetermined angle as shown in FIG. 4, the notch 21a of the bar latch 41 and the small diameter portion 8c (FIG. 2) formed at the rear end of the shaft 8a of the tool 8 are connected. This disengages the tool 8 from the position shown in FIG.
By pulling to the left in the drawing, the tool 8 can be taken out from the hole 13a of the final spindle 13 disposed in the head 9.

Furthermore, by rotating the bar latch 41 by a predetermined angle counterclockwise about the shaft 20 shown in FIG. Since it is expanded, oil can be supplied to the inside of the head 9 and the inside of the elbow 3 through the first and second oil filling holes 30 and 31 at the rotational position of the bar latch 41 shown in FIG. The work of expanding the first and second oil filling holes 30, 31 during maintenance and inspection becomes extremely easy.

After installing the new tool 8 in the head 9, the bar latch 41 is rotated by a predetermined angle clockwise from the rotation position of the bar latch 41 shown in FIG. For example, similarly to FIGS. 2 and 3, the notch 21a formed above the bar latch 41 engages with the small diameter portion 8c formed at the rear end of the shaft portion 8a of the newly inserted tool 8, and the corresponding A bar latch 41 is installed in which the tool 8 is immovably mounted in the head 9, the second oil fill hole 31 is closed by the surface of the bar latch 41, and the first oil fill hole 30 is also extended. The first and second oil fill holes 30, 31 are closed at the same time by a protrusion 41b formed on the back surface of the lower end 41a, which makes it extremely easy to close the first and second oil fill holes 30, 31 during maintenance and inspection.

[Effects of the invention] As explained above, with this invention, the oil lubrication holes formed at two locations on the dental contra-angle can be closed and expanded at the same time by a simple operation of rotating the bar latch that prevents the tool from being pulled out. This prevents oil from flowing out of the oil hole when the dental contra-angle is operated when it is closed, and also prevents dust from entering the contra-angle through the oil hole and preventing its smooth operation. Since the operation is not hindered, it is possible to provide a dental contra-angle that maintains stable function.

In addition, since it has a simple structure in which the rear end of the conventional bar latch is extended and a protrusion is formed at the lower end, the number of parts does not increase and manufacturing is simple, so the increase in manufacturing costs can be suppressed as much as possible. You can also do it.

In addition, by simply rotating the bar latch, the oil fill holes formed in two locations can be closed and opened at the same time, making it extremely easy to fill the oil holes during maintenance and inspection. It has excellent effects.

[Brief explanation of the drawing]

Fig. 1 is a conceptual diagram of the dental contra-angle according to this invention, Fig. 2 is a cutaway cross-sectional view of the main part of Fig. 1, Figs. 3 and 4 are right side views of Fig. 2, and Fig. 5
The figure shows a conceptual diagram of a conventional dental contra-angle.
Figure 6 is a cross-sectional view of the main parts of Figure 5, Figures 7 and 8.
The figure is a right side view of FIG. 2. 3...Elbow, 8...Tool, 9...Head, 1
2...First gear transmission means, 14...Second gear transmission means, 30...First oil filling hole, 31...
...Second oil lubrication hole, 40...Dental contra angle, 41...Bar latch, 41a...Lower end (extended end), 41b...Protrusion.

Claims (1)

[Claims for Utility Model Registration] Having a first gear transmission means inside, and the first gear transmission means;
an elbow formed with a first oil lubrication hole for supplying oil to the gear transmission means; a second gear transmission means mounted above the elbow and having a second gear transmission means therein; A tool mounting head formed with a second oil lubrication hole for supplying oil; rotatably supported by the head; and a notch at the upper end of the head for preventing the tool mounted on the head from coming off; , a dental contra angle having at least a bar latch whose surface closes the second oil filling hole in a rotational position to prevent the tool from being removed; The first oil filling hole is extended to the position of the first oil filling hole, and a protrusion is formed at the extending end thereof to fit into and engage with the first oil filling hole at a rotational position to prevent the tool from coming off. A dental contra-angle that is characterized by the following features: