JPH01250247A - Chuck apparatus of dental handpiece - Google Patents

Abstract

PURPOSE:To obtain the subject apparatus simple to detach and having structurally high safety, by providing such a structure that a cutting tool can be simply mounted only by inserting the a chuck releasing press cap in a pressed state. CONSTITUTION:When a cutting tool is mounted, the bar B of the tool is merely inserted in a chuck pipe 13 from below in such a state that a press cap 18 is pressed. Whereupon, the upper end of the bar is simply inserted in a clamp pipe 7 up to the predetermined position reaching the annular projection 10 thereof. Next, when the pressing of the cap is released, the outer periphery of the bar is tightened by the truncated cone part 15 pressed by a spring material 12 and a conical pipe part 18 to be fixed strongly. When external force ready to draw acts on the bar in this fixed state, the truncated cone part of the chuck part is further strongly pressed to a clamp pipe conical part structurally and, therefore, the unexpected pull-off of the tool is prevented almost completely and high safety can be obtained. The cutting tool can be simply detached by pushing the press cap to push down a screw member head part 11a and releasing the tightening of the chuck pipe.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a chuck device for a dental handpiece that allows easy attachment and detachment of cutting tools and the like and is highly safe.

<Prior Art> Various types of chuck devices for dental handpieces have been proposed.

<Problem to be solved by the invention> However, it is easy to attach and remove cutting tools, etc.
Furthermore, there has not yet been proposed a highly structurally safe device that will not allow tools to fall out even when tools are attached.

The present invention has been made in view of such conventional problems.

<Means for Solving the Problems> The features of the present invention include a cylindrical rotating shaft rotatably supported within the head, and a cylindrical rotating shaft inserted into the rotating shaft and a lower end inner side of the rotating shaft. is formed with a conical tube portion with a tapered diameter, and has a clamp tube with an upper end protruding from the rotating shaft, and a lower end inserted into the rotating shaft, and an upper end inserted into the clamp tube that extends in the axial direction. The chuck tube is formed with an extending slit and has a truncated conical portion formed on its outer periphery to fit with the conical tube portion of the clamp tube, and a spring member that biases the clamp tube upward with a spring force. Found in the chuck device of a dental handpiece.

<Function> In this chuck device, when a tool, etc. is attached, if the clamp tube is pushed down against the spring bias of the spring material, the clamping of the chuck tube is released, and in this state, the bar of the tool, etc. is held in the chuck tube. It can be easily attached by simply inserting it from the lower tip. After this attachment, if the clamp tube is released, the spring bias of the spring material will cause the inserted tool etc. to be attached to the outer periphery of the bar.
Since the truncated conical portion of the chuck tube pressed into the conical tube portion of the clamp tube bites, tools etc. are firmly tightened and fixed.

In this fixed state, if an outward force is applied to the bar of the tool, etc. to try to pull it out, the truncated conical portion of the chuck tube will be structurally pressed even more strongly against the conical tube portion of the clamp tube. Therefore, inadvertent removal of tools, etc. is almost completely prevented. In other words, extremely high safety can be obtained.

<Embodiment> FIG. 1 shows an embodiment of a chuck device for a dental handpiece according to the present invention.

In the figure, 1 is the head of the handpiece, and a cylindrical rotating shaft 4 rotatably supported by two bearings 3 is installed approximately in the vertical direction of the central shaft inside the case 2. There is. An impeller 5 is attached to the intermediate outer periphery of the rotating shaft 4 between the bearings 3, 3, and by blowing compressed air onto the impeller 5, the rotating shaft 4 is rotated at high speed. An O-ring 6.6 for vibration isolation is attached to the outer periphery of each of these bearings 3.3.

A clamp tube 7 is inserted inside the rotary shaft 4, which is thus rotatable. A conical tube part 8 is formed inside the lower end of this clamp tube 7, and the inner diameter becomes smaller toward the distal end, that is, the conical tube part 8 is tapered in diameter. It protrudes from the portion 4a. A threaded portion 9 and an annular projection 10 are formed from the opening on the inside of this upper end protruding portion. This annular protrusion 10 is a bar B of a cutting tool, etc., as described later.
This acts as a stopper that determines the insertion stroke. A screw member 11 is screwed onto the screw portion 9, and a coil-shaped spring member 12 is mounted between the screw member head 11a and the upper end of the rotating shaft 4.

The clamp tube 7 is always biased upward by the spring material 12. In other words, the clamp tube 70 conical tube section 8 is pulled upward.

On the other hand, a chuck tube 13 is inserted from the lower end of the rotating shaft 4 to the center. One or more slits 14 extending in the axial direction are formed at the upper end of the chuck tube 13, and a truncated conical section 15 that fits into the conical tube section 8 of the clamp tube 7 is formed in sections on the outer periphery. ing. This truncated cone portion 15 is cut by cutting 14.
With the outer diameter of the clamp tube 7 reduced, the conical tube portion 8 of the clamp tube 7
passed through. After insertion into the conical tube section 8, the truncated conical section 15 of the chuck tube 13 returns to its original state due to the elasticity of the chuck tube material (metal material).
is mated with. Incidentally, this fitting assembly is preferably carried out before each of the sounds 7 and 13 is inserted and mounted on the rotating shaft 4. Further, on the outer periphery of the chuck tube 13 near the lower end, there is a stepped portion 1.
6 is formed, and this stepped portion 16 is adapted to be engaged with the lower end portion of the rotating shaft 4 as a stopper.

Further, at the upper end of the head 1, above the screw member 11,
Pressing cap 1 elastically biased by internal leaf spring 17
8 is installed. If you press this cap for a day,
The clamp tube 7 is connected to the spring member 1 via the screw member 11.
It is pushed downward against the spring force of 2. As the clamp tube 7 descends, the conical tube section 8 is also pushed down, so that the pressing force of the chuck tube 13 against the truncated conical section 15 becomes weaker, and the chuck is released from tightening.

Note that 20 is a preload member for the lower bearing 3.

In the case of the chuck device of the present invention configured as described above, when a cutting tool or the like is attached, the pressing cap 1 is
8 in a pressed state B (with the clamp tube 7 pressed down against the biasing force of the spring material 12), simply press the bar B of a cutting tool, etc.
can be inserted into the inside of the chuck tube 13 from the lower end. Then, the upper end of the bar becomes the annular projection 10 of the clamp tube 7.
It is easily inserted until it reaches the desired position. After this insertion,
When the pressure on the pressing cap 18 is released to make it free, the outer periphery of the bar B is constantly pressed by the truncated conical portion 15 of the chuck tube 13 due to the pressure of the spring material 12 and the conical tube portion 8 of the clamp tube 7. Because it is tightened, it is firmly fixed.

In this fixed state, when an external force acting on the bar B such as a cutting tool to cause it to come off, a similar force acts on the chuck tube 13 integrated with the bar 8. For example, at point 19, which is the cutting tool part of the bar B, cutting is often performed by pressing the tip 19a against the tooth to be treated, but sometimes the shoulder 19b is pressed against the tooth to be treated. In some cases, the bar B is used in such a way that the bar B is pulled up and the point 19 is pulled up. It is also conceivable that such an outward force action is caused by other causes.

In any case, due to such an outward force, the truncated conical portion 15 of the chuck tube 13 naturally tries to move in the same direction, so that the truncated conical portion 15 gradually reduces the inner diameter of the clamp tube 7. Due to the conical tube portion 8, it is pressed even more strongly.

Therefore, the tightening of the truncated conical portion 15 to the bar B becomes even stronger, and the bar B, such as a cutting tool, is almost completely prevented from coming off. In other words, high safety can be obtained.

Note that when removing the cutting tool, etc., press the pressing cap 18 as described above to remove the head 11 of the screw member 11.
It can be easily removed by pushing down the chuck tube 13 and releasing the fastening of the chuck tube 13.

FIG. 2 shows another embodiment of the chuck device for a dental handpiece according to the present invention.

This chuck device is substantially the same as that of the embodiment shown in FIG. It is interposed between the portions 13b.

As a result, the clamp tube 7 is always in the free state.
Spring biased upward. The functions and usage of each part in this case are exactly the same as those shown in FIG. 1 above.

<Effects of the Invention> As is clear from the above description, according to the present invention, cutting tools, etc. can be easily attached and removed by simply inserting the chuck release press cap while being pressed. It is possible to provide a chuck device for a dental handpiece that is structurally safe and prevents tools from accidentally coming off.

[Brief explanation of the drawing]

FIG. 1 is a partial longitudinal sectional side view showing one embodiment of the chuck device for a dental handpiece according to the present invention, and FIG. 2 shows another embodiment of the chuck device for a dental handpiece according to the present invention. FIG. 3 is a partially longitudinal side view. In the figure, ■... Head of handpiece, 3... Bearing, 4... Rotating shaft, 5... Impeller, 7... Clamp tube, 8... Conical tube part, 9... Threaded part, 10... Annular projection, 11... Screw member, 12... Spring, material, 13... Chuck tube, 14... Cut, 15... ... truncated conical part, 16... step part,

Claims (3)

[Claims] (1) A cylindrical rotating shaft rotatably supported within the head;
a clamp tube that is inserted into the rotating shaft, has a conical tube portion with a tapered diameter formed inside its lower end, and has an upper end protruding from the rotating shaft; A chuck tube is formed with a slit extending in the axial direction at the upper end inserted into the tube, and a truncated cone portion is formed on the outer periphery of the chuck tube to fit with the conical tube portion of the clamp tube. A dental handpiece chuck device consisting of a spring material that applies an upward spring force. (2) The chuck device for a dental handpiece according to claim 1, wherein the spring material is interposed between the clamp tube and the rotating shaft. (3) The chuck device for a dental handpiece according to claim 1, wherein the spring material is interposed between the clamp tube and the chuck tube.