JPH01305308A - Measuring apparatus for shape of spectacle lens frame - Google Patents

Abstract

PURPOSE:To enable highly-precise three-dimensional measurement of the shape of a spectacle lens frame by a method wherein a spectacle frame being held, a stylus having a disk-shaped head is rolled and moved along the V-shaped inner peripheral groove of the lens frame thereof. CONSTITUTION:A spectacle frame F being fixed and held, the head 32 of stylus 30 is brought into contact with the V-shaped inner peripheral groove of a lens frame Fr. When a microcomputer of a control circuit is put in operation, a rotary table 2 rotates and the stylus 30 rolls in contact with the inner peripheral groove of the frame Fr. A rotary encoder 9 is rotated with the rotation H of a measuring element 1 and an angle theta of rotation is detected. The amount of movement in the radial direction of the stylus 30 is detected as the amount (r) of movement in the direction R of a slide plate 16 by a linear encoder 24, while the amount of movement in the vertical direction is detected as the amount (z) of movement in the direction Z of the stylus 30 by a CCD line image sensor 34. Receiving an origin signal of the encoder 9 as an input, CPU memories the respective count values of the encoder 24 and the sensor 34, the data on the axes (r) and (z), sequentially corresponding to an angle signal of the encoder 9. The data theta, (r) and (z) are inputted to an arithmetic circuit and the three-dimensional shape of the frame Fr is thereby determined.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an eyeglass lens frame shape measuring device for three-dimensionally measuring the shape of an eyeglass lens frame.

[Conventional technology]

The outline of the lens frame of an eyeglass frame has a shape such as a circle, a square, or an oval in order to accommodate the lens.

Furthermore, when viewing the lens frames from above or below while wearing glasses, the left and right lens frames are arranged on a curve that matches the shape of the human face.

Therefore, in order to accurately obtain information on the shape of eyeglass lens frames, in addition to measuring the two-dimensional shape of the frame when viewed from the front, it is necessary to measure the curved shape of the lens frame when viewed from above or below, and whether the left and right lens frames are on the curve. It is necessary to know in what position it is placed. In order to realize this, a three-dimensional measuring device has been developed (Japanese Patent Application Laid-Open No. 62-169008 and Japanese Patent Application Laid-Open No. 62-169009).

[Problem that the invention seeks to solve]

However, the three-dimensional measuring device treats the radial displacement r of the contact point of the lens frame and the height direction displacement 2 of the contact point as an angle of rotation about a point outside the lens frame, so The angular displacement is small and difficult to measure accurately. Further, although angular changes are detected using a rotary encoder, only a portion of the measurement range (one rotation) of the rotary encoder can be used, so the rotary encoder must be large in order to increase resolution.

The present invention has been made to eliminate the drawbacks of the above-mentioned conventional techniques, and its purpose is to provide an eyeglass lens frame shape measuring device that can three-dimensionally measure the eyeglass lens frame shape with high precision.

[Means for solving problems]

This purpose is, according to the present invention, a means for moving the stylus in the horizontal direction and a means for moving the stylus in the vertical direction in order to move the disc-shaped head of the stylus as a measuring point along the inner circumference of the lens frame of the eyeglass frame. and a scale for measuring the horizontal displacement of the stylus or the member holding the stylus, the vertical displacement of the stylus or the member holding the stylus; and means for measuring the angle of rotation of the stylus or the member holding the stylus with respect to said arbitrary point.

[Example] Next, an example of the present invention shown in the drawings will be described in detail.

The eyeglass lens frame shape measuring device according to the present embodiment holds an eyeglass frame and moves a stylus having a disc-shaped head along a figure-7 inner circumferential groove of a lens frame of the eyeglass frame while moving the stylus. The movement of the stylus is measured in three dimensions, and FIG. 1 shows the coordinate system for this measurement.

In Fig. 1, 0 is an arbitrary point in the lens frame Fr, P is a point on the inner groove of the lens frame Fr, r is the horizontal distance from O to P, 2 is the vertical distance from 0 to P, and θ is O It is the angle rotated on the horizontal plane around r, z.

The shape of the lens frame Fr is measured by measuring and calculating θ.

2 and 3 show the entire spectacle lens frame shape measuring device without the spectacle frame holding means. FIG. 2 is a perspective view of the present device, and FIG. 3 is a view of the present device in FIG. 2 as viewed in the ■ direction.

This device consists of an eyeglass frame F held stationary in a predetermined position by an eyeglass frame holding means (not shown).
The lens frame Fr is provided with a measuring section l for measuring the lens frame Fr. This measuring unit 1 is equipped with a U-shaped rotary table 2, and this rotary table 2 is rotationally driven in the θ direction by a motor 6 via a timing boot I73 attached to the lower end surface, a timing belt 4, and a timing pulley 5. Ru. This angle of rotation is determined by the timing pulley 3 attached to the rotating table 2.
It is detected by a low-return encoder 9 connected via a timing belt 7 and a timing pulley 8. The motor 6 and the rotary encoder 9 are fixed to a substrate 10 of the measuring device (only a part of which is shown in FIG. 2 to make it easier to see other parts of the measuring device), and the timing pulley 3 and the rotary encoder 9 are The stand 2 is rotatably supported on the substrate 10 by a bearing (not shown).

The rotary table 2 of the measuring section 1 consists of two side plates 11 and 12, and a rectangular center plate 13 that connects the two side plates. Two slide guide shafts 14 and 15 are fixed in parallel between the side plates 11 and 12. A horizontal slide plate 16 is slidably guided in the R direction along this slide guide shaft 14,15. For this purpose, the slide plate 16 is provided with three rotatable slide guide rollers 17, 18, and 19 on its lower surface. In this case, two slide guide rollers 17, 1B are in contact with one slide guide shaft 14, one slide guide roller 19 is in contact with the other slide guide shaft 15, and these rollers 17, 18, 19 The slide guide shafts 14 and 15 are transferred from both sides along the slide guide shafts.

A constant force spring (Conston spring) 20 acts on the sliding plate 16 in the sliding direction R, and one side plate 1
being pulled towards 2. This spring 20 is wound around a bushing 21 and fixed to the side plate 12 via a shaft 22 and a bracket 23. The other end of the constant force spring 20 is attached to the slide plate 16. The spring 20 has the function of pressing a stylus, which will be described later, against the inner circumferential groove of the lens frame Fr.

The movement 1ir of the slide plate 16 in the backward direction is measured by a non-conforming linear encoder 24 as a displacement measurement scale. This linear encoder 24 is connected to the side plate 1 of the rotary table 2.
1 and 12, a detector 26 fixed to the slide plate 16 and moving along the scale 25, an amplifier 27, and the amplifier 27 and the detector 26.
and a flexible cable 28 for connecting. The amplifier 27 is attached to the bracket 2 fixed to the side plate 12.
It is attached to 9.

By moving the slide plate 16, the detector 26 moves while maintaining a constant distance from the surface of the scale 25. In response to this movement, the detector 26 outputs a pulse signal to the amplifier 27 connected to the flexible cable 28. The amplifier 27 amplifies this signal and sends it to a counter to be described later.

A stylus 3 as a probe is mounted on the slide plate 16.
0 is retained. The stylus 30 is supported by a sliding bearing in a sleeve 31 fixed to the slide plate 16 so as to be movable up and down (Z direction) and rotatable. The stylus 30 has a disc-shaped head 32, which comes into contact with the inner circumferential groove of the lens frame Fr by the action of the constant force spring 200, and is moved along the inner circumferential groove of the lens frame by the rotation of the rotary table 2. Roll.

At this time, the stylus 30 moves in the radial direction in accordance with the shape of the lens frame Fr. The amount of movement in the radial direction, that is, the amount of movement r in the R direction, is measured by the linear encoder 24 via the sleeve 31 and the slide plate 16, as described above.

Further, the stylus 30 moves in the Z direction in accordance with the curve of the lens frame Fr. A Z-axis measuring device 33 formed as a displacement measurement scale detects the amount of movement in the Z direction. As shown in detail in FIGS. 4 and 5, this Z-axis measuring device 33 is composed of a charge-coupled device (CCD) line image sensor 34 and a light emitting diode (LED) 35 as a light source. installed.

The CCD line image sensor 34 and the LED 35 are arranged facing each other. Since the stylus 30 moves up and down between the two according to the curve of the lens frame Fr, the CCD line image sensor 34 is blocked by the stylus 30.
The boundary between the shadow of the stylus 30 and the bright area above also moves up and down.

Therefore, by detecting the distance from the edge of the measurement surface of the CCD line image sensor 34 to this boundary, the stylus 3
A displacement 2 in the Z direction of 0 can be measured. The CCD line image sensor 34 exchanges the brightness of each point on the measurement surface into voltage, and uses an externally applied start pulse to sequentially start from the end of the measurement surface of the CCD line image sensor 34 in synchronization with an external clock. Since a voltage corresponding to this brightness is output, this voltage is binarized at an arbitrary level by a comparator, and the voltage from the start pulse to the point where the binarized signal changes from 0 to 1, that is, the point at the border of the shadow, is The amount of vertical movement of the stylus is measured by counting the number of clocks (see Figure 6).

Furthermore, this device is equipped with a motor rotation limit mechanism 36 for stopping the motor 6 after measurement, as shown in FIGS. 3 and 7. This mechanism consists of a rotation limit fitting 37 fixed to the side of the swimming pool 'J3, a vertical shielding rond 38 operated by this fitting, a shielding plate 39 integrally formed with this shielding rond, and It consists of springs 40a and 40b that movably support the shielding plate and shielding rod by pulling them from both sides, and photoinclusters 41a and 41b that cooperate with the shielding plate 39. Both springs 40a
, 40b are attached to the substrate IO. Photo ink clubters 41a and 41b are also attached to the substrate 10 in the same way, and two are provided corresponding to the forward and reverse rotations of the rotary table 2. The rotation limit fitting 37 is connected to the shielding rod 3
8, the shielding plate 39 will cover the photo ink printers 41a and 4.
A signal obtained by the shielding plate 39 passing through 1b and blocking the light is input to the control circuit, and the motor 6 is stopped.

Next, the operation of the eyeglass lens frame shape measuring device having the above structure will be explained.

The eyeglass frame F is fixedly held by an eyeglass frame holding means (not shown), and the head 32 of the stylus 30 is attached to the lens frame F.
Bring it into contact with the 7-shaped inner circumferential groove of r.

When a measurement start switch (not shown) is turned on, the motor 6 rotates according to instructions from the microcomputer of the control circuit 42 (see FIG. 8), the rotary table 2 connected by the timing belt 4 rotates, and the stylus 30 rotates. Lens frame Fr
Transfers while contacting the inner circumferential groove. The rotation of the measuring part 1 is
A rotary encoder 9 connected by a timing belt 7 is rotated and detected as a rotation angle (θ). The amount of radial movement of the stylus 300 is determined by the linear encoder 24.
The moving amount (r) of the slide plate 16 in the R direction is detected by the CCD line image sensor 34, and the moving amount in the vertical direction is detected as the moving amount (r) of the stylus 30 in the Z direction.
) is detected as At this time, when the microcomputer inputs the origin signal of the rotary encoder 9, it outputs the counter value of the linear encoder 24, which is r-axis data, and the CCD line image, which is two-axis data, in response to the angle signal of the rotary encoder 9. Sensor 340 counter values are stored in memory in sequence. These data (θ, [
, 2) are input to an arithmetic circuit (not shown), and the three-dimensional shape of the lens frame Fr is determined.

Then, when the rotary table 2 rotates once and the origin signal of the row reencoder 9 is inputted again, data storage is stopped, the rotation limit fitting 37 pushes the shielding rod 38, and the shielding plate 39 moves the photo ink controller 41a. Or block the light of 41b. The motor 6 is stopped by inputting the resulting signal to the control circuit 42.

Further, the eyeglass frame holding means (not shown) can be slid to measure the other lens frame Fr while holding the eyeglass frame F, and moves the stylus 30 into the other lens frame Fr. Lens frame measurements can be performed. Since the sliding amount of the spectacle frame holding means is set to a constant value in advance, the relative positional relationship between both lens frames can be known from this set value and the measurement data of both lens frames Fr. The measured data or calculated data here is output to another computer via the interface 43 (see FIG. 8).

The present invention is not limited to the above embodiments.

For example, instead of the linear encoder 24 and the Z-axis measuring device 33, other displacement measurement scales (for example, electromagnetic induction type, magnetic type, or optical displacement measurement scale) may be used.

[Effects of the Invention] As described above, the spectacle lens frame shape measuring device of the present invention has the following advantages:
Since the horizontal displacement and vertical displacement of the stylus or the member holding the stylus are measured as linear displacements without converting them to angles, it is possible to measure the lens frame shape with extremely high accuracy. can.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing the measurement principle of an eyeglass lens frame shape measuring device according to an embodiment of the present invention, FIG. 2 is a perspective view of the device, and FIG.
The figure is a view of this device as seen in the ■ direction of Figure 2, Figure 4 is a perspective view of the Z-axis measuring instrument, Figure 5 is a vertical cross-sectional view of the Z-axis measuring instrument, and Figure 6 is a diagram of the Z-axis measuring instrument. A diagram showing the signal processing method of the CCD line image sensor, S7'' Figure 7 is a perspective view showing a motor rotation limit mechanism for stopping the motor, Figure 8 is a detection circuit diagram of the eyeglass lens frame shape measuring device. 1...Measuring part, 2...Rotary table, 3,5°8...
・Timing pulley, 4, 7...Timing belt, 6...Motor, 9...Low reencoder, 10...Board, 11°12...Side plate,
13...Central plate, 14°15...Slide guide shaft, 16...Slide plate, 17.
18.19...Slide guide roller, 20...
・Constant force spring, 21...Bushing, 22・
...Axis, 23...Bracket, 24...Linear encoder, 25...Scale, 26...Detector, 27...Amplifier, 28...Flexible cable, 29...Bracket, 30 ... Stylus, 31... Sleeve, 32... Head, 33... Z-axis measuring device, 34... CCD line image sensor, 35... LED. 36... Motor rotation limit mechanism, 37... Rotation limit fitting, 38... Shielding rod, 39
...Shielding plate, 40a, 40b...Spring, 41
a, 41b...Photo ink book, 42...
Control circuit, 43...interface, F...
Eyeglass frame, Fr...lens frame, 0...any point, P...point on the lens frame, R...movement direction of the slide plate, r...horizontal distance between 0 and P , Z
...Vertical movement direction of the stylus, 2...0 and P
Vertical distance between e...Rotation direction of rotating table, θ・
...Rotation angle of P with respect to 0, Applicant Hoya Co., Ltd. Agent Patent Attorney Shizuo Nakamura No. 18

Claims (1)

[Claims] 1. Means for moving the stylus in the horizontal direction, means for moving the stylus in the vertical direction, and a lens frame in order to move the disc-shaped head of the stylus as a measuring tip along the inner circumference of the lens frame of the eyeglass frame. a scale for measuring the horizontal displacement of the stylus or the member holding the stylus; a scale for measuring the vertical displacement of the stylus or the member holding the stylus; and an eyeglass lens frame shape measuring device, comprising means for measuring the rotation angle of the stylus or the member that holds the stylus, with reference to any of the above points.