JPS62169008A - Apparatus for measuring groove shape for fixing lens of spectacles frame - Google Patents

Abstract

PURPOSE:To find the degree of a curve of a groove for fixing lens of a spectacles frame, by measuring the shape of the lens fixing groove of the spectacles frame three-dimensionally. CONSTITUTION:When measuring a groove for fixing lens of a spectacle frame three-dimensionally, it is required to know coordinates on the Z axis 14, the amount theta of rotation when a spectacles frame is turned on the Z axis and a distance gamma of the frame from the Z axis at the rotation. Then, the Z coordinates are obtained from an encoder 6, the gamma from an encoder 4 and the angle theta of rotation is obtained from the number of pulses given to a pulse motor 11 from the initial position determined by a light shielding plate 13 and a photosensor 12. Thus, 3-D coordinate value can be determined.

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field of the Invention) The present invention relates to a shape measuring device for a lens fixing groove of an eyeglass frame.

(Background of the Invention) A V-shaped groove for fitting a lens is formed in an eyeglass frame. This structure is curved to match the curvature of the lens. Therefore, the above-mentioned lens fixing groove has a three-dimensional shape.

However, conventional devices for measuring the lens groove shape of eyeglass frames of this type have a structure that two-dimensionally measures the shape of either the left or right side of the eyeglass frame when the frame is viewed from the front.

Therefore, there is a drawback that it is difficult to know the degree of curvature of the lens fixing groove.

(Objective of the Invention) An object of the present invention is to solve these drawbacks and provide a measuring device for the shape of a lens fixing groove that can also determine the degree of curvature of the lens fixing groove of an eyeglass frame.

(Summary of the Invention) The technical point of the present invention is to solve the conventional drawbacks by three-dimensionally measuring the shape of the lens fixing groove of an eyeglass frame.

(Embodiment) Fig. 1 is a perspective view of the mechanical part of the first embodiment of the present invention, in which a measuring arm 1 has a stylus 2 at its tip, and the other end can freely rotate around a shaft 3. It is supported as such. A rotary encoder 4 is attached to the shaft 3 to measure the movement of the stylus 2 at the tip of the measuring arm 1 in the direction of arrow j1. This encoder 4 is an absolute encoder for measuring absolute position or an incremental encoder with an origin signal. Measuring arm 1, stylus 2, shaft 3, and encoder 4 are all centered around shaft 5 as shown by the arrow! , is supported by a support member 7 so as to be able to rotate freely in the force direction, and the amount of rotation is measured by a rotary encoder 6. This encoder 6 is also an absolute encoder capable of measuring absolute position or an incremental encoder with an origin signal. The stylus 2 moves along a groove in the frame portion of the eyeglass frame 1010 under the weight of the measuring arm 1. The eyeglass frame 8 is fixed to the frame rotating plate 10 via frame fixing members 9a, 9b, and 9a. The frame rotating plate 10 has teeth cut on its outer periphery and is rotated by a pulse motor 11. In addition, the photosensor 1 for initial position detection
A light shielding plate 13 is attached to shield light from light.

When performing three-dimensional measurement of the lens fixing groove of an eyeglass frame, the coordinates on the two axes 14, the amount of rotation θ when the eyeglass frame is rotated around the two axes, and the distance γ of the frame from the two axes at that time. It's good if you know.

In this embodiment, the two coordinates are determined by the encoder 6, γ
Since the rotation angle θ is determined by the encoder 4 and the number of pulses applied to the pulse motor 11 from the initial position determined by the light shielding plate 13 and the photosensor 12, three-dimensional coordinate values can be obtained. Note that since it is sufficient to know the relative position in the direction of arrow l and force, the encoder 6 may be an incremental encoder that can only know the relative position.

FIG. 2 is a block diagram of an electrical circuit used with the mechanical portion of FIG. 1. The pulse generator 21 generates clock pulses in response to command signals from the microcomputer 20. This pulse a drives the pulse motor 11 and is counted by the counter n. The initial position signal obtained when the photosensor 12 is shielded from light by the light shielding plate 13 resets the counter n and is also input to the microcomputer. The microcomputer operates according to a flowchart as shown in FIG. That is, when a measurement start switch (not shown) is turned on, the microcomputer drives the pulse generator 21 (step 31), and when the initial position signal output from the photosensor 12 is input (step 32), the count value of the counter n is input. The count values of encoders 4 and 6 are stored in correspondence with (step 33). Then, when the initial position signal is input again (step 34), the eyeglass frame 8 has been rotated once, so from the data acquired in step 33, the center of the eyeglass frame and the lens fixing groove relative to the center of the eyeglass frame are determined. The radius and curve values are calculated (step 35) and stored as data (step 36).

With such a configuration, the eyeglass frame 8 is fixed to the frame rotating plate 10 by the frame fixing members 9a, 9b, and 9c, and after dropping the stylus 2 into the lens fixing groove, the measurement start switch is turned on. Glasses frame 8
The shape of the lens fixing groove can be determined three-dimensionally.

Although the above example uses a stylus as the measuring section, the stylus 2 may be replaced with a non-contact photoelectric sensor as shown in FIG.

The sensor body 40 is provided with a light source 41, a projection lens 12, a focusing lens 43, and a position detector 44.
The light is projected onto the bottom 80 of the groove of the eyeglass frame by a projection lens, and the reflected light is received by a position detector through a condensing lens 43.The position detector 44 detects a light point in the direction of the arrow. When the eyeglass frame 80 moves from position P to Pt, the light intensity center position on the position detector 44 changes, and the sensor body 4
It is possible to detect that the distance between 0 and the frame has changed. Also, if the projected light deviates from the groove,
This means that the distance has changed by the depth of the groove, and the positional shift can be detected from the change in the center of gravity position of the light quantity of the weak position detector.

In this case, the sensor body 40 is fixedly installed at the tip of the measuring arm 1 shown in FIG.
The frame shape is measured from the output of the encoder attached to the servo motor by controlling the servo motor so that the 0 is always at a constant position with respect to the frame groove.

Note that in the above embodiments, the entire circumference of the eyeglass frame was measured by rotating the eyeglass frame, but there is no problem in this method in which the measurement system is rotated.

(Effects of the Invention) As described above, according to the present invention, the shape of the lens fixing groove of an eyeglass frame can be measured in three dimensions.

Conventional equipment R (moulding machine) for measuring the shape of lens grooves in eyeglass frames does not measure in two directions at all, but only traces the shape of the grooves in eyeglass frames in two dimensions. By measuring in three dimensions, we can obtain much more information about the frame shape than before.

Generally, the lens fixing groove of an eyeglass frame has the shape of the frame in two dimensions, but in three dimensions it has a shape that is further curved in two directions. That is, it is a three-dimensional shape obtained by further projecting the two-dimensional frame shape onto a spherical surface centered in the Z-axis direction. In other words, the shape of the groove is a collection of points on a spherical surface, and the radius K of this sphere is a numerical value called the frame force, which is a curve value when machining a spectacle lens. Conventionally, no measurements were taken on the curve K, and the beading process was performed based on the experience and intuition of the processor.
When fitting a lens into a frame, parts that do not fit have been corrected by modifying the lens or deforming the 7-nm lens to make it fit. However, according to the present invention, the three-dimensional shape of the eyeglass frame groove is measured, so if the beading process is performed based on the measured value, the frame can be inserted without deforming the eyeglass frame or distorting the lens. It is possible.

In addition, in general, a sphere of radius γ centered at a point (a, b, c) in space is (X a)"+ (Y b)"+ (Z c)'
= r'', so a, b, c, and γ can be found by substituting the measured values obtained from the lens fixing groove of the eyeglass frame, which is originally made into a spherical shape, into the above equation. Since the value r determined here corresponds to the curve of the eyeglass frame, it is extremely effective to know the curve value K that should be set when processing lenses using a conventional abrasive machine.

[Brief explanation of drawings]

Fig. 1 is a perspective view of the mechanical part of the first embodiment of the present invention;
The figure is a block diagram of an electric circuit used in conjunction with the mechanical part of Figure 1, Figure 3 is a flowchart of the microcomputer used in Figure 2, and Figure IX4 explains the senna main body 4o of the second embodiment of the present invention. This is a diagram for (Explanation of symbols of main parts) 1...Measuring arm, 2...Stylus, 4, 6...Encoder, 9a, 9b, 9cm7 frame fixing member, 1
゜... Frame fixing plate, 11... Pulse motor,
12... Photo sensor for initial position detection, 13... Light shielding plate, 20... Microcomputer, 40... Senna main body.

Claims (1)

[Scope of Claims] A holding member that holds the eyeglass frame from the outside; a means for detecting the position of a lens fixing groove provided in the inner space of the eyeglass frame; and a means for detecting the position of the groove provided in the inner space. The first penetrating
a first holding means for holding the detecting means movably in the first direction; and a first holding means for detecting the amount of movement of the detecting means in the first direction.
a movement amount detection means; a second holding means for holding the groove position detection means movably in a second direction orthogonal to the first direction; and a second holding means for detecting the movement amount of the detection means in the second direction. a second movement amount detection means; a rotation means for relatively rotating the eyeglass frame and the detection means with the first direction as a rotation center; and a rotation position of the detection means relative to the eyeglass frame by the rotation means as an absolute position. The detection signals of the first movement amount detection means, the second movement amount detection means, and the rotation position detection means are inputted, and the detection signals of the rotation position detection means are inputted to correspond to the detection signals of the rotation position detection means. A measuring device for the shape of a groove for fixing a lens in an eyeglass lens, comprising: a storage means for storing the detection signal of the first movement amount detection means and the second movement amount detection means.