JPH05344980A - Attitude measuring device for handpiece - Google Patents

Abstract

PURPOSE:To obtain a measuring device which is small-sized and permits high precision and can grasp the result of measurement as the numerical data. CONSTITUTION:Each tilt angle on the three-dimensional coordinates of a handpiece A is calculated by a calculation means C from the detection signal of a semiconductor type accelerating speed sensor B installed on the handpiece A, and the result of the calculation is outputted. Accordingly, the attitude of the handpiece is detected with high precision for the three-dimensional coordinates, the numerical data a be obtained, and the data can be applied to the usage in a wide range such as the educational device in handpiece operation, besides at the site for therapy, by outputting the result of the calculation in a variety of modes.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for measuring the posture of a dental handpiece and displaying the result.

[0002]

2. Description of the Related Art It is necessary to maintain the orientation of the bar at the tip of the handpiece in the case of machining the peripheral surface of an abutment tooth or machining a pin hole, and therefore various proposals for detecting the posture of the handpiece Has been done. Examples include a spherical inclinometer with a structure that detects the attitude based on the position of the bubble, or a vertical meter with a structure in which the ball for blocking the optical path moves and light reaches the light receiving element when tilted. And the like (see, for example, Japanese Utility Model Publication No. 57-157318, Japanese Utility Model Publication No. 50-2707, etc.). However, all of these have low accuracy, and the orthogonal X,
Of the three-dimensional coordinates of the Y and Z axes, only the inclination in the X and Y directions can be known, and it is difficult to grasp the inclination angle as numerical data.

[0003]

In view of this point, the present invention has a small size and high accuracy so that the measurement result can be grasped as numerical data and can be displayed and utilized by various output means. The task was to do.

[0004]

In order to achieve the above object, the attitude measuring device for a handpiece according to the present invention comprises a semiconductor type acceleration sensor attached to the handpiece and a detection signal from the semiconductor type acceleration sensor. The calculation unit includes a calculation unit that calculates each tilt angle of the handpiece with respect to the three-dimensional coordinate axes and outputs a signal based on the calculation result, and an output unit that displays the calculation result according to the output signal. A CRT display can be used as the output means, and is configured to display the calculation result as an image of the handpiece by computer graphics technology.

A printer is used as an output means,
It is configured to output the calculation result as an image of the handpiece or a hard copy of a numerical value. Further, a sound generator may be used as the output means and the calculation result may be notified by sound or voice. FIG. 1 is a diagram showing a configuration of the present invention, in which A is a handpiece, B is a semiconductor type acceleration sensor, C is a calculation means, and D is an output means. D ₁ is a CRT
A display, D ₂ is a printer, and D ₃ is a speaker which is an example of a sound generator.

[0006]

The tilt angles of the handpiece with respect to the three-dimensional coordinate axes are detected by a small semiconductor acceleration sensor. Also, since the attitude of the handpiece is calculated from the detection signal,
The calculation result can be displayed by an output means such as a CRT display, a printer, a sound generator, etc., and the posture of the handpiece can be output and used in various modes according to the application.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment shown in the drawings will be described below. In FIG. 2, 1 is a handpiece, 2 is a bar provided at the tip of the handpiece, 3 is a hose, and 4 is a hose joint for connecting the hose 3 to the handpiece 2. 5x, 5
Reference numerals y and 5z denote semiconductor type acceleration sensors, for example, in which a mounting recess is formed on the outer periphery of the hose joint 4 in a state where a constant relationship is maintained with respect to the handpiece 1 and main axes thereof are orthogonal to each other. It is attached by an appropriate means such as fitting into. This is because the hose joint 4 is connected to the handpiece 1 while maintaining a constant relationship, and the acceleration sensor is the most suitable member that does not interfere with the operation of the handpiece.
Instead, it can be attached to the body of the handpiece 1. The acceleration sensors 5x, 5y, 5z may be semiconductor type sensors capable of detecting gravitational acceleration. For example, a semiconductor piezoelectric element is used, and the sensitivity is highest when the main axis is vertical, and the vertical line corresponding to the inclination of the main axis is used. Angle of CO
A structure in which the output changes in proportion to S (cosine) is used.

FIG. 3 is a block circuit diagram of the apparatus.
x, 6y, 6z are sensor amplifiers for amplifying the detection signals of the respective sensors 5x, 5y, 5z to a level capable of A / D conversion, 7 is a multiplexer, 8 is a filter, 9 is an A / D converter, 10 is control It is a department. A personal computer having a CPU 10a, a memory 10b, a keyboard 10c, etc., can be used as the control unit 10, and a CRT display 11, a printer 12, and a speaker 13 are connected as output devices. The printer 12 may be a plotter, or a speaker 13 may be replaced by a sound generator such as a buzzer.

The embodiment is configured as described above, and the detection signals of the sensors 5x, 5y, 5z corresponding to the attitude of the handpiece 1 are amplified by the sensor amplifiers 6x, 6y, 6z,
A / D converter 9 is sequentially switched by the multiplexer 7.
Is input to the control unit 10 after being A / D converted. The filter 8 is a low-pass or band-pass filter having a characteristic of passing only an analog signal component corresponding to the inclination of the main axis of each sensor 5x, 5y, 5z,
The noise signal included in the detection signal of each sensor, for example, the noise signal such as the vibration of the motor driving the bar 2 of the handpiece 1 is removed by the filter 8. The control unit 10
The inclination of each sensor, that is, the attitude of the handpiece 1 is calculated from the input detection signals of the sensors 5x, 5y, and 5z according to a predetermined algorithm, and the result is output by the CRT display 11, the printer 12, or the speaker 13. Has been done.

The attitude of the handpiece 1 is obtained as follows. Now, as shown in FIG. 4, each sensor 5x, 5y, 5z
When the main axis of is directed to the X-axis, the Y-axis, and the Z-axis of the orthogonal coordinate axes, respectively, the angle from the X-axis in the XY plane is θxy, the angle from the X-axis in the XZ plane is θxz,
When the angle from the Z axis on the XZ plane is θzx, the output Vx of the sensor 5x is Vx = G · cos θxy · cos θxz cos θxz = cos (90 ° −θzx) = sin θzx Therefore, Vx = G · cos θxy · sin θzx (1) To be done. However, G is a constant determined by gravity and the sensitivity of the sensor.

Similarly, the output Vy of the sensor 5y is Vy = G · cos θyz · sin θxy (2), and the output Vz of the sensor 5z is Vz = G · cos θzx · sin θyz (3). Is (1) above
It is a simultaneous equation of equations (2) and (3).

Therefore, by solving this simultaneous equation, the angle θx
By obtaining y, θyz, θzx, that is, the inclination of each sensor, the attitude of the handpiece 1 at that time can be calculated. Here, the coordinates and the reference posture of the handpiece are not absolute, and may be arbitrarily selected by an initial setting operation. Note that the angles θxy, θ
In the case where yz and θzx are small and the output of the sensor is substantially proportional to the angle, a simple method omitting the calculation of a complicated trigonometric function may be adopted, and the angle can be calculated by a relatively simple process. The calculation result is appropriately output in real time or stored in the memory 10b for future use, and the processing algorithm may be appropriately set according to the sensor type and the output format.

As the output format, for example, the numerical value of the tilt angle with respect to each coordinate axis is displayed on the CRT display 11 based on the calculation result, or the image of the handpiece 1 is converted into the above calculation result by using computer graphics technology. It can be displayed on the CRT display 11 in a posture based on it. FIG. 5 exemplifies the image 1 ′ of the handpiece displayed on the CRT display 11. In addition, the printer 12 can output a numerical value or an image in the form of a hard copy, or the speaker 13 can output sound according to the numerical value, or a signal sound that changes according to the inclination can be output. Output formats are possible.

In the above embodiment, three single-axis type acceleration sensors are used, but one three-dimensional sensor capable of detecting the tilt angle in all directions may be used. FIG. 6 shows an example of such a sensor 5. That is, n-Si wafers 22 and 23 are attached to both sides of a frame 21 made of a glass-based material, a thin diaphragm 24 is formed at the central portion of the wafer 22, and a weight 25 is supported at the center of the diaphragm 24. 8 formed on the surface
(4 pairs) of diffusion gauges 26 on the peripheral bonding pads 2
7 has a structure in which wiring is made. The overall size is a square with a side of 6 mm, and the thickness is 2.4 mm, which is very small compared to a handpiece and is also lightweight.

The above diffusion gauge 26 is a kind of piezoelectric element, and in the state shown in the figure, the diaphragm 24 receives downward gravity and the inner four of the eight gauges 26 receive the same strain, and the outer one. Receive the same magnitude but opposite phase distortion. Further, when the sensor 5 is tilted, the strain applied to each changes depending on the tilt, so that the posture of the sensor 5 with respect to the three-dimensional coordinates can be calculated from the output of the gauge 26 due to these strains. ..

As described above, according to the apparatus of this embodiment, the attitude of the handpiece 1 is detected, but the acceleration sensor 5
Alternatively, since 5x, 5y, and 5z are semiconductor type and are extremely small and lightweight, they do not hinder the operation of the handpiece 1. Also, when displaying an image on the CRT display 11, it is possible to visually understand the posture of the handpiece 1, and if it is output by the printer 12, the hard copy can be used for time for study and study. When the posture is displayed by voice or sound, it is possible to know whether or not the operation of the handpiece 1 is appropriate with the line of sight directed toward the workpiece. Therefore, this device is not only useful for processing abutment teeth in the actual treatment field, but is also suitable for, for example, a simulation device in an educational setting and can be used for various purposes. Is.

[0017]

As is apparent from the above description, the present invention calculates each tilt angle on the three-dimensional coordinate of the handpiece from the detection signal of the semiconductor type acceleration sensor attached to the handpiece, and the calculation result Is output. Therefore, the posture of the handpiece can be detected with high accuracy in three-dimensional coordinates to obtain numerical data, and the calculation results can be output from this data in various formats, so that it can be used only in the field of treatment. Therefore, it is possible to obtain a device that can be applied to a wider range of purposes such as education for handpiece operation.

Further, in the case of displaying an image on the CRT display, the posture of the handpiece can be visually understood, and in the case of outputting the calculation result in the form of a hard copy, time-consuming examination and the like become easy, Further, in the case where the calculation result is displayed by voice or sound, the posture of the handpiece can be understood audibly, so that a device which is suitable for each use and is effective and effective can be obtained. Further, according to the present invention, there is also an effect that a simple fluctuation measurement can be performed by pressing the bar at the tip of the handpiece against the tooth with wobbling and measuring the wobbling angle.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of the present invention.

FIG. 2 is a side view of the handpiece according to the embodiment of the present invention.

FIG. 3 is a block circuit diagram of the embodiment.

FIG. 4 is a diagram illustrating a mounting state and operation of an acceleration sensor.

FIG. 5 is a diagram exemplifying an image of a handpiece displayed on a CRT display.

6A and 6B are a cross-sectional view and a plan view illustrating a three-dimensional acceleration sensor.

[Explanation of symbols]

 1 Handpiece 1'Image of handpiece 2 Bar 4 Hose joint 5,5x, 5y, 5z Semiconductor type acceleration sensor 10 Control unit 10a CPU 10b Memory 11 CRT display 12 Printer 13 Speaker

Claims (4)

[Claims] 1. A semiconductor type acceleration sensor attached to a handpiece, and a calculating means for calculating each inclination angle with respect to the three-dimensional coordinate axis of the handpiece from a detection signal of the semiconductor type acceleration sensor and outputting a signal based on the calculation result. An attitude measuring device for a handpiece, comprising: and an output means for displaying a calculation result according to the output signal. 2. The attitude measuring device for a handpiece according to claim 1, wherein the output means is a CRT display, and the calculation result is displayed as an image of the handpiece by computer graphics technology. 3. The posture measuring device for a handpiece according to claim 1, wherein the output means is a printer, and the calculation result is output as an image of the handpiece or a hard copy of a numerical value. 4. The posture measuring device for a handpiece according to claim 1, wherein the output means is a sound generator, and the calculation result is notified by sound or voice.