JP2879482B2 - Eyeglass lens processing machine and eyeglass lens processing method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a spectacle lens processing machine and a spectacle lens processing method for grinding a peripheral portion of a lens blank into a shape that can be fitted to an inner peripheral surface of a rim of a spectacle frame. This is an improvement of the beveling process performed after rough grinding of the peripheral portion of the steel sheet.

[0002]

2. Description of the Related Art Conventionally, as this kind of eyeglass lens processing machine and processing method, there is known an eyeglass lens processing machine described in JP-A-59-156657. In the spectacle lens processing machine described in this publication, a beveled curved surface to be applied to the peripheral portion of a lens blank after rough grinding and serving as a reference when performing beveling is specified by the following procedure. That is, first, the center of curvature of each of the front surface and the back surface of the lens blank is calculated, and then the bevel curvature center is set at a predetermined position of the optical axis passing through the obtained two points of curvature center. The bevel surface was specified by the bevel radius of curvature. Further, as another method for specifying a beveled surface, for example, a method described in Japanese Patent Publication No. 1-27212 is known. This specifying method is based on the premise that the bevel curvature center exists on the axis of a pair of lens axes that sandwich the lens blank, and at least two or more of the outer peripheral side surfaces of the lens blank set based on a predetermined criterion. This is calculated and specified based on the bevel apex position.

[0003]

However, in any of the above-described conventional examples, when the center of the bevel curvature is obtained, the condition that the center of the bevel curvature exists on the optical axis or on the axis of the lens axis is satisfied. Need to be done. Therefore, in the calculation process for specifying the bevel curved surface, the axis at which the center of the bevel curvature is present has higher priority than other conditions. It was extremely difficult to form a bevel vertex at a desired position. As a result, when the processed spectacle lens is fitted to the inner peripheral surface of the rim of the spectacle frame, it is a derivative problem that it is not possible to meet the customer's demand for suppressing the amount of protrusion of the surface of the spectacle lens from the rim. Will occur. Responding to customer demands for such aesthetics has become extremely important today in the manufacture of spectacle lenses. Further, as another major problem, when the lens blank is sandwiched between a pair of lens axes, if the optical center of the lens blank is largely decentered from the axis of the lens axis, a bevel vertex cannot be formed on the outer peripheral side surface of the lens blank. This can happen in some cases. Further, in the former conventional example, when determining the center of curvature of the back surface, even if the back surface is a toric surface, since the calculation is performed by approximating the spherical surface, the back surface curvature center position serving as a reference of the bevel curvature center position is used. There is also a problem that the bevel curvature center position is naturally inaccurate because it is inaccurate.

The present invention has been made in view of the above-mentioned problems, and an object thereof is to give priority to a bevel apex position set on the outer peripheral side surface of a lens blank in a calculation process for specifying a bevel curvature radius. By doing
It is an object of the present invention to provide a spectacle lens processing machine and a spectacle lens processing method capable of performing a bevel processing so that a bevel vertex exists at a desired position on an outer peripheral side surface of a lens blank.

[0005]

The present invention SUMMARY OF] has been made in order to achieve the above object, the rotation thereof the first invention comprises a pair of lens axis sandwiching the front and back surfaces of the lens blank, the lens axis A lens holding unit having a driving device for moving along the lens axis direction and rotatably supported in a direction perpendicular to the lens axis, and reciprocating the lens holding unit in the lens axis direction. Moving means for moving, comprising a rotating grindstone formed on the surface with a rough grinding surface and a beveled grinding surface having a beveled groove for grinding the peripheral portion of the lens blank sandwiched by the pair of lens axes,
The lens blank held between the pair of lens shafts is subjected to a rough grinding process in which a peripheral portion thereof is pressed against a rough grinding surface of the rotating grindstone to form a shape larger than an inner circumferential contour shape of a rim of a predetermined eyeglass frame. After that, by moving the lens holding unit by the moving means and pressing the rough-ground lens blank against the beveled grinding surface of the rotating grindstone, the peripheral edge of the lens blank is placed on the inner peripheral surface of the rim of the eyeglass frame. In a spectacle lens processing machine that bevels into a fittable shape, three-dimensional coordinates defined by a Z-axis that is coincident with or parallel to the axis of the pair of lens axes and an rθ plane that is perpendicular to the Z-axis are set. An rθ value (r: moving radius from a reference point, θ: rotation angle from a reference angle) for specifying a contour shape similar and approximate to the inner peripheral contour shape of the rim of the spectacle frame is described. To rθ storing means and reads out the rθ value stored in the rθ storage means, Seki this rθ value
Three local maximums in the order of increasing value of r among the local maximums of the number r
For three angles θ corresponding to these local maxima.
A measurement position determination means for three locations determined measurement points of Z value of the peripheral portion of the lens blank to kick, and Z value measuring means for measuring the respective Z values of the surface and the back surface at the measurement point determined by the measurement position determination means A bevel apex position setting means for setting a predetermined bevel apex position between the front surface measurement point and the back surface measurement point at a peripheral portion of the lens blank; and the coordinate values of the set bevel apex in the rθ storage means. and stored rθ values, a first calculating means for calculating the Z value obtained by the Z value measuring means, resulting et in the first arithmetic means
Coordinate value of each bevel vertex and bevel curvature radius storage means
Of curvature center from bevel curvature radius R read from
A second calculating means for specifying the bevel curvature, and processing the peripheral edge of the roughly ground lens blank into a shape that can be fitted to the inner peripheral surface of the rim of the spectacle frame. After pressing the peripheral portion against the beveled grinding surface of the rotating grindstone, based on the calculation result obtained by the second calculation means, the moving means is operated to move the lens holding unit along the lens axis. The beveling is performed such that the bevel apex position formed over the entire outer peripheral side surface of the lens blank is positioned on the beveled curved surface calculated by the second calculating means .

In a second aspect, the front and back surfaces of the lens blank are
A pair of lens axes to be sandwiched and this lens axis is rotated
It has a driving device and is movable along the lens axis direction.
And rotatably supported in a direction perpendicular to the lens axis.
Lens holding unit and the lens holding unit
Moving means for reciprocating in the axial direction of the lens;
The peripheral edge of the lens blank held between the lens axes
Rough ground surface to be ground and bevel ground surface with bevel groove
A rotating grindstone formed on the surface, wherein the pair of lens axes
The peripheral part of the lens blank sandwiched by
It is pressed against the AraKen cutting surface of the grinding wheel in a predetermined spectacle frame Li
Roughening to form a shape larger than the inner peripheral contour shape
After shaving, the lens is held by the moving means.
Move the unit to rotate the rough-ground lens blank
By pressing against the beveled grinding surface of the whetstone,
Rim of the eyeglass frame with the inner peripheral surface of the rim of the eyeglass frame
For eyeglass lens processing machine that bevels into a shape that can fit in
Z that coincides with or is parallel to the axis of the pair of lens axes.
Axis and a third order defined by an rθ plane perpendicular to the Z axis.
Set the original coordinates, the inner contour of the rim of the eyeglass frame
Rθ value that specifies a similar and approximate contour shape
(R: moving radius from reference point, θ: rotation angle from reference angle)
Storage means for storing the
Read out the rθ value obtained,
Maximizes the distance from any extreme point to another extreme point
The two extreme points are determined as the first and second measurement points, and
Are located on both sides of the dividing line connecting these two extreme points.
The two extreme points to be placed are determined as the third and fourth measurement points
Measuring position determining means;
Measure the Z values of the front and back surfaces at the specified measurement points.
Z-value measuring means, and a peripheral portion of the lens blank
Te, predetermined bevel between the surface measurement point and the rear surface of the measuring points
A bevel apex position setting means for setting a vertex position, the setting
The coordinate value of the determined bevel vertex is stored in the rθ storage unit.
The stored rθ value and the Z value obtained by the Z value measuring means
And a first calculating means for calculating from the coordinates
From the center of the bevel curvature to the first and second measurement points
The condition that the distances are equal to each other and the center of the bevel curvature
Distances from the measurement points to the third and fourth measurement points are equal to each other
Calculates the curvature center coordinate value of the beveled surface under the condition
Further, based on the coordinate value of the bevel vertex,
And a second calculating means for calculating the bevel curvature by calculating
The edge of the rough-ground lens blank is
When processing into a shape that can fit into the inner peripheral surface of the rim of the
The edge of the lens blank is
After pressing against the cut surface, the calculation result obtained by the second calculation means is obtained.
The moving means is actuated based on the result and the lens holding unit is operated.
By moving the knit along the lens axis,
Formed over the entire outer peripheral side surface of the lens blank.
The bevel vertex position calculated by the second calculating means.
So as to be positioned on the down curved surface, characterized and this <br/> to perform beveling.

In a third aspect, the front and back surfaces of the lens blank are
A pair of lens axes to be sandwiched and this lens axis is rotated
It has a driving device and is movable along the lens axis direction.
And rotatably supported in a direction perpendicular to the lens axis.
Lens holding unit and the lens holding unit
Moving means for reciprocating in the axial direction of the lens;
Of the lens blang sandwiched between the lens axes
Rough ground surface to be ground and bevel ground surface with bevel groove
A rotating grindstone formed on the surface, wherein the pair of lens axes
The peripheral part of the lens blank sandwiched by
Press against the rough grinding surface of the rotating grindstone to fix the eyeglass frame
Roughening to form a shape larger than the inner peripheral contour shape
After shaving, the lens is held by the moving means.
Move the unit to rotate the rough-ground lens blank
By pressing against the beveled grinding surface of the whetstone,
Rim of the eyeglass frame with the peripheral edge of the blank
Eyeglass lens processing method to bevel the shape into a shape that can fit in
In, coincident or parallel to the axis of the pair of lens axes
3 defined by the Z axis and an rθ plane perpendicular to the Z axis
Set the dimensional coordinates, the inner circumference contour of the rim of the eyeglass frame
Rθ value that specifies a contour shape similar and approximate to the shape
(R: moving radius from reference point, θ: rotation angle from reference angle)
Storing the rθ, and storing the rθ
Is read out, and r of the function of this rθ value is read out.
Search for three maxima in the order of increasing r value among maxima of
And three angles θ corresponding to these local maxima.
Three measurement points of Z value on the periphery of lens blank
The measuring position determining step and the measuring position determining step
Each Z value of the front and back surfaces at the measurement point determined
Measuring a Z value, and
At the periphery, between the front surface measurement point and the back surface measurement point
Set the bevel vertex position
And the coordinate value of the set bevel apex is rθ
The rθ value stored in the storage step and the Z value measuring means
A first calculation step of calculating from the obtained Z value;
A coordinate value of each bevel vertex obtained in the first calculation step;
The bevel tune read from the bevel curvature radius storage step
Identify the bevel curvature by calculating the center of curvature from the radius of curvature R
A second operation step, wherein the rough-ground lens blank is
Can be fitted to the inner peripheral surface of the rim of the spectacle frame
When processing the lens blank,
After pressing the edge against the beveled grinding surface of the rotating grindstone, the second
The movement based on the calculation result obtained in the calculation step.
Activate the means to move the lens holding unit to the lens axis.
Along the outside of the lens blank.
The bevel apex position formed over the entire area of the peripheral side is
Located on the beveled surface calculated in the second calculation step
It is characterized in that the beveling is performed as described above.

In a fourth aspect, the front and back surfaces of the lens blank are
A pair of lens axes to be sandwiched and this lens axis is rotated
It has a driving device and is movable along the lens axis direction.
And rotatably supported in a direction perpendicular to the lens axis.
Lens holding unit and the lens holding unit
Moving means for reciprocating in the axial direction of the lens;
The peripheral edge of the lens blank held between the lens axes
Rough ground surface to be ground and bevel ground surface with bevel groove
A rotating grindstone formed on the surface, wherein the pair of lens axes
The peripheral part of the lens blank sandwiched by
Press against the rough grinding surface of the rotating grindstone to fix the eyeglass frame
Roughening to form a shape larger than the inner peripheral contour shape
After shaving, the lens is held by the moving means.
Move the unit to rotate the rough-ground lens blank
By pressing against the beveled grinding surface of the whetstone,
Rim of the eyeglass frame with the inner peripheral surface of the rim of the eyeglass frame
Eyeglass lens processing method to bevel the shape into a shape that can fit in
In, coincident or parallel to the axis of the pair of lens axes
3 defined by the Z axis and an rθ plane perpendicular to the Z axis
Set the dimensional coordinates, the inner circumference contour of the rim of the eyeglass frame
Rθ value that specifies a contour shape similar and approximate to the shape
( R: moving radius from reference point, θ: rotation angle from reference angle)
Storing the rθ, and storing the rθ
The rθ value stored in the rθ value function is read out and the
The distance from any extreme point to another extreme point is
Determine the two extreme points as the first and second measurement points
And on both sides of the dividing line connecting these two extreme points.
The two extreme points respectively located are referred to as third and fourth measurement points.
Determining a measurement position determining step;
Front and back surfaces at measurement points determined by Tep
A Z value measuring step for measuring each Z value of the lens lens;
Measurement of the front surface measurement point and the back surface at the periphery of the rank
Set bevel vertex position between points Bevel vertex position
Setting step and the coordinate value of this set bevel vertex
With the rθ value stored in the rθ storage step and Z
The first performance calculated from the Z value obtained in the value measurement step
Calculation step and the coordinates of the top of the bevel
Distance from the center of curvature to the first and second measurement points
From the center of the bevel curvature and
Under the condition that the distances to the fourth measurement point are equal to each other,
Calculating the coordinates of the center of curvature of the curved surface;
Calculate the bevel radius of curvature based on the coordinate values of the vertices and
A second operation step of determining a curvature
Rim of the eyeglass frame
When processing into a shape that can be fitted to the inner peripheral surface of
Press the peripheral edge of the lens blank against the beveled grinding surface of the rotating grindstone
Then, based on the operation result obtained in the second operation step,
Then, the moving means is operated to operate the lens holding unit.
By moving the lens along the lens axis,
Bead formed over the entire outer peripheral side of the lens blank
Bevel position calculated at the second calculation step
Performing beveling so that it is located on a curved surface
It is characterized by.

[0009]

The eyeglass lens processing machine according to the first and third inventions
And the processing method, the measurement position determining means
The rθ value stored in the storage means is read, and the rθ value
Three maxima in the order of increasing r value among the maximal values of r of the function
Check the values and determine the three angles θ corresponding to these local maxima.
Measurement points of Z value of the peripheral part of lens blank
I have decided. Also, the bevel vertex position setting means
Surface measurement point and back surface measurement at the periphery of lens blank
Set the bevel vertex position between the point and the first calculation
Means calculates the coordinate value of the top of the bevel,
The bevel surface is specified based on the coordinate values of the points. Second
In the arithmetic means of the above, obtained by the first arithmetic means
Coordinate values of three bevel vertices and bevel curvature radius storage means
Bevel based on bevel radius of curvature R read from
The bevel curved surface is specified by calculating the rate center coordinate value.

The eyeglass lens according to the second and fourth inventions
According to the machine tool and the processing method,
From any extremal point in the extremum of the rθ function to another extremal point
The first and second extreme points at which the distance to
Selected as a measurement point, and a dividing line connecting the two extreme points
The two extreme points respectively located on both sides are
Determined as a measurement point. Also, the second computing means
Of the bevel surface based on the coordinate values of the top of the bevel
When calculating the coordinate value of the center of curvature,
Condition that the distance from the first to the second is equal to each other
And the distance from the center of the bevel curvature to the third and fourth
Calculates the bevel radius of curvature of the bevel surface on condition that
Out and specify the bevel curvature.

[0011]

BRIEF DESCRIPTION OF THE DRAWINGS FIG.
Eyeglass lens processing machine and eyeglass lens processing method according to
Will be explained. FIG. 1 shows an eyeglass lens processing machine according to the present invention.
FIG. 3 is a perspective view of main components and mechanisms showing one embodiment,
Lens blank 6 before (or lens blank after rough grinding)
A) a lens holding unit 24 for holding the lens
Diamond for grinding the periphery of blank 6 or 60
A wheel 1, an arm 33 supporting the homer 20,
Moving means 2 for lens holding unit 24 and arm 33
9 is mainly shown. Figure 2 measures the rθ value of the lens blank
FIG. 3 is a side view of the rθ measuring means, and FIG.
FIG. 4 is a perspective view of the measuring means, and FIG. 4 is an electric circuit of the eyeglass lens processing machine.
FIG. The eyeglass lens processing machine according to the present invention is
Rough grinding of the periphery of the lens blank 6 following the shape of 0
Then, beveling is performed on the periphery.
In this embodiment, the axis of a lens axis described later is Z
Axis, and a plane orthogonal to the Z axis is an rθ plane.
The coordinates are defined by the rθ plane. Also, measure the rθ value.
Rθ measuring means 300 holds the lens as shown in FIG.
A Z-value measuring device arranged below the unit 24 for measuring the Z-value
The setting means 200 includes the lens holding unit 24 as shown in FIG.
Are arranged on the front side, but both are shown in FIG.
Not.

Here, the rθ value is the contour of the lens blank.
The lens blank is measured in this example.
With reference to the axis of a pair of lens axes that sandwich the front surface of
An arbitrary point located on the periphery from this reference point is represented by r (radial radius).
And θ (square seat) in polar coordinates.

Now, referring to FIG.
The eel 1 is mounted on a rotatable spindle 5.
The main motor (shown in FIG. 1)
) Is the power transmitted from the pulley 2 and belt 3
Transmission at a constant speed by transmission through the
It is configured to be inverted. In lens grinding work,
The diamond wheel 1 is a rotating bear,
Is pressed against the peripheral edge of the lens blank 6 and is ground.
The diamond wheel 1 has a rough cylindrical shape.
Rough grinding stone (mesh: # 100) 1b for grinding
Beveling wheel (mesh: # 400) 1a for shaving
And fixed to the spindle 5 with the fixing screw 1c.
With a vertex angle of 120 ° on the circumferential surface of the beveled grinding wheel 1a.
Bevel groove 1a ₁ of is formed.

The lens blank 6 includes a lens holding shaft 7.
And the lens support shaft 8 (hereinafter referred to as the lens shaft
Lens holding shaft 7 and lens support shaft 8
You. ) Sandwiches the front and back surfaces. On the lens holding shaft 7
Means that the rotational force of the chucking motor 9 is
Is transmitted through the client 11. Chucking motor 9
When the feed screw 12 is rotationally fed by the rotational force,
The lens holding shaft 7 can move in the axial direction.
You. In the mechanism relating to the feed screw 12, the rotation of the feed screw 12 is performed.
A female screw is inserted into the inner diameter hole of the pulley 11 so that
So that the feed screw 12 is screwed into this female screw.
It is configured. By moving the lens holding shaft 7 in the axial direction,
The lens blank 6 can be freely attached to and detached from the eyeglass lens processing machine.
Can be. That is, the lens holding shaft 7 is connected to the lens support shaft.
8 in the direction approaching the lens support shaft 8 and the lens
The lens blank 6 can be clamped between the
Direction in which the lens holding shaft 7 is separated from the lens support shaft 8
To remove the lens blank 6.
Wear.

The rotation of the lens blank 6 is controlled by a lens holding shaft.
This is performed by rotating the lens 7 and the lens support shaft 8. Ma
The rotation of the lens motor 13 via the gears 14 and 15
The rotation shaft 16 rotates. The rotational force of the lens motor 13 is
Further, pulleys 17 and 1 fixed to both ends of the rotating shaft 16 are provided.
7, each of the lens holding shaft 7 and the lens supporting shaft 8
Pulleys 19, 19 provided, wound between these pulleys
The lens holding shaft 7 is passed through the belts 18
Is given to the lens support shaft 8. Thus, the lens push
The shaft 7 and the lens support shaft 8 are connected to a common lens motor 13.
Rotational force is given to rotate in a synchronized state. In addition, above
The lens motor 13 described above is composed of a pulse motor,
As shown in FIG.
It operates on the basis of the pulse signal passed through.

The homer 20 is an unprocessed lens blank.
To give the target shape of grinding
The shape is the same as the rim inner circumference contour shape of the eyeglass frame
(Yes). Houma 20 and the lens blank 6
Means that the two ends of the lens support shaft 8 are coaxial
It is fixed and arranged in a positional relationship. Lens blank 6
As described above, the lens holding shaft 7 and the lens support shaft 8
While being held, the homer 20 is connected to the lens support shaft 8 and the homer.
It is clamped by a holding member 52. Therefore, the lens model
The lens 13 rotates and the lens holding shaft 7 and the lens support shaft
8 rotates, the lens blank 6 and the homer 20 are shared.
Rotates in a synchronized state. In this example, the shape of the homer 20 is shown.
Is the same as the inner contour of the rim of the eyeglass frame.
However, they do not necessarily have to be the same,
It only has to be similar.

The pulley 19 provided on the lens support shaft 8
On the left side in FIG. 1, a slit 100 is formed in the radial direction.
Further, a disk-shaped slit plate 101 is provided. this
The slit plate 101 emits light from the photo interrupter 102
・ The light emitted from the light emitting element rotates between the light receiving elements and slips.
It passes only at the position of 100. As shown in FIG.
The detection signal detected by the photo interrupter 102 is
00, and this detection signal is used as a reference for θ in the rθ value.
Since the angle is indicated, the lens motor 13 is operated.
Since it becomes the reference signal of the pulse signal to be
6 can be determined.

Lens holding indicated by a two-dot chain line in FIG .
The unit 24 has a flat surface with a recess formed in the center on the near side.
The case 24A has a U-shaped case. As mentioned earlier,
King motor 9, lens motor 13, lens holding shaft 7
And components such as lens support shaft 8 and various power transmission mechanisms
The element is disposed at a predetermined location in the case 24A, and
The lens holding unit 24 is configured by the components.
The lens blank 6 to be processed is a front concave portion of the case 24A.
It is arranged at a substantially central position of the place. Lens holding unit 24
As described below, the slide shaft 25 is used as a rotation center.
Swingable in the direction perpendicular to the lens axis as shown by arrow L1
And moves in the axial direction (Z-axis direction) of the slide shaft 25.
It is attached to the place. With this mounting structure,
Blank placed in the recess of the lens holding unit 24
6 can be freely moved vertically and horizontally.
Can be. In the lens holding unit 24, the lens
Sandwiched lenses Blanc in presser 7 and lens support shaft 8
6 is caused by the weight of the lens holding unit 24 during grinding.
Pressed against diamond wheel 1.

The slide shaft 25 has two bearing receivers.
Slide trays held inside the respective tables 26, 26
Rotating and moving in the Z-axis direction by the ring 27
Mounted as possible. Lens holding unit 24
Is connected to the slide shaft 25 via a slide bearing 24a.
Fixed. In addition, the slide shaft 25 is
Lens holding shaft 7 and the lens support shaft 8
You.

At the left end of the slide shaft 25,
Holding table having a profile plate 43 that comes into contact with the homer 20
The base end of the arm 33 on which the
Therefore, it is attached so as to be rotatable vertically. or,
From the lower surface of the base end of the arm 33, the rack 10
T-shaped rack member 104 formed with
The rack 103 is a rotating shaft of the electromagnetic clutch 105.
To be engaged with the pinion 106 disposed at one end of the
ing. The other end of the shaft of the electromagnetic clutch 105 has a pulley 1
07, and the pulley 107 and the Z-axis mode
To the pulley 110 attached to the tip of the shaft of the
A timing belt 109 is stretched. Electromagnetic crack
H 105 is free bevel processing (lens holding unit 2)
4 is beveled in a state where it can move freely in the lens axis direction.
Off), the lens holding unit is turned off.
24 is moved in the Z-axis direction by the Z-axis motor 108.
ON when the power of the Z-axis motor 108
To the rack member 104 via the timing belt 109
introduce. This Z-axis motor 108 is also a pulse motor.
As shown in FIG.
Driven by a pulse signal sent through the
You. Incidentally, the above-mentioned trailing plate 43 of the holding table 42 is
It has a surface with the same radius of curvature as the processing surface of Mondo wheel 1.
I have.

The holding table 42 is supported below the holding table 42.
And a support mechanism for the elevator 44 are provided.
You. As described above, the arm 33 moves in the Z-axis direction.
In, the roller 45 is provided between the holder 42 and the temperature Fudai 44
The holding table 42 slides on the roller 45.
ing.

Reference numeral 49 denotes a lens holding unit at the time of moving a process or the like.
24 is a Y-axis motor that moves up and down. This Y-axis motor
By rotating 49, the elevator 44 is
As shown in L3, in the Y-axis direction (vertical direction in FIG. 1)
Can be raised and lowered. When the elevator 44 is raised,
First, the profile plate 43 rises and comes into contact with the homer 20,
When the ascent continues, the contact plate 43 maintains the contact state.
And Houma 20 both rise. Houma 20 is home presser
The lens 52 is held between the member 52 and the lens support shaft 8, and
The shaft 8 is a bearing (not shown) which is a lens holding unit 2.
4, the homer 20 moves upward.
And the lens holding unit 24, as shown by the arrow L1,
The ascending rotation is performed using the slide shaft 25 as a rotation fulcrum. Opposition
Then, when the elevator 44 is lowered, the copy plate 43 is lowered.
Following this, the lens holding unit 24 moves by its own weight.
Descend. In addition, 50 and 51 indicate the elevating movement of the elevating table 44.
It is a supporting member for supporting. Also, this Y-axis motor
Reference numeral 49 denotes a pulse motor, as shown in FIG.
500 sent from interface 500 via interface 501.
It is driven by a loose signal.

As described above, the lens holding unit 24
The Z-axis motor 108 moves in the Z-axis direction,
Swings up and down around the slide shaft 25,
The lens blank 6 to be processed
Can be moved. In addition, it swings up and down
As a result, the lens blank 6 is
Can be moved on the Tiremond Wheel 1
You.

Next, referring to FIG.
explain. First, the slide on the back of the lens holding unit 24
A pair of left and right L-shaped arms 11 is attached to the id bearing 24a.
0, 111 (where 111 is the shadow of 110 in FIG. 2)
(Not hidden).
A slide shaft 112 extends between 0 and 111.
You. To measure the rθ value, a lens blank (Araken
Kezunochi) 60 and diamond wheel 1 and shape which is brought into contact with
In the state, the lens shaft 7 holding the lens blank 60,
When the lens 8 is rotated by the lens motor 13 (FIG. 1),
Variation of the radial radius r of the lens blank 60 at a predetermined angle θ
, The lens holding unit 24 moves the slide shaft 25
The arm 11 swings in the direction of arrow A with the center as the center.
0 and 111 also follow and swing in the direction of arrow B. Also,
The slide shaft 112 provided between the arms 110 and 111
Is a slide that is slidably inserted into and supported by the guide cylinder 114.
It is rotatably attached to the tip of the id shaft 115.
Roller 119 has published. This roller 119 is
Slide when the holding unit 24 moves in the Z-axis direction.
Roll along axis 112.

The slide shaft 115 is connected to the arm 110
(111) is arranged at an angle in a direction substantially perpendicular to
Is biased by the spring 120 toward the arm 110 (111).
I have. A rack 1 is provided at the base end of the slide shaft 115.
16 is formed, and the rack 116 is
-Engage with the pinion 118 of the encoder 117
You. Therefore, the arms 110 and 11 are changed according to the change in the moving radius r.
When 1 swings up and down, the slide shaft 115 also moves up and down.
The amount of movement is detected by the rotary encoder 117
Then the lens shaft 7, 8 and the rotation on the diamond wheel
The amount of change in the distance (H) between the axis and the axis of rotation is detected. And
Detection signal detected by this rotary encoder 117
Is the reference angle θ _{0 of the} lens blank 60 as shown in FIG.
Sent from the photo interrupter 102 that detects
It is sent to the CPU 500 together with the reference angle signal. CPU5
00, the detection signal and the reference angle signal
The following calculation is performed. First, as shown in FIG.
The trajectory 400 of the tip of the axis distance (H) about the axis of the shaft
Draw all around. Next, the die 400
With the rotation center of the diamond wheel 1 positioned,
Move the diamond wheel 1 along the trace 400
You. The inner envelope 401 obtained at this time is the rθ value.
You. The r obtained by the calculation by the CPU 500 in this manner
The θ value is stored in the RAM 502 (r
θ storage means).

Next, with reference to FIG. 3 and FIG.
The means 200 will be described. Front side of lens holding unit 24
This Z value measuring unit 200 arranged in
Measuring element having a probe 201 and a second probe 202 at the tip.
The measuring shaft 204 protruding downward from the base end of the
The rotary cylinder 205 rotates by itself through a bearing (not shown).
The rotary cylinder 205 is further disposed on the outer periphery.
Via a bearing (not shown)
It is rotatably supported. In addition, the first tracing stylus 2
01 and the second tracing stylus 202 are as shown in FIG.
It has an inverted truncated cone shape. Also, the lower end of the rotary cylinder 205
A driven pulley 207 is disposed in the section.
Side pulley 207 and the rotation axis of Z value measurement motor 215
The timing between the drive pulley 208 and the
Guberto 209 is suspended. This Z value measurement model
The motor 215 is a pulse motor, and as shown in FIG.
Sent from PU 500 via interface 501
It is driven by an incoming pulse signal. This Z value measurement mode
The rotation cylinder 205 rotates by driving the
Therefore, when measuring the Z value, the measurement arm
Arranged at a solid line position (measurement position A) orthogonal to axes 7 and 8
The lens axis can be set when not measuring.
To the one-dot chain line position (retreat position B) parallel to
be able to. Each stop at the measurement position A and the retreat position B
Is controlled by a stop signal from a sensor (not shown).
Also, at the lower end of the measuring shaft 204 described above,
Arm formed with slit plate 210 having slits
211 is disposed so as to be perpendicular to the measuring arm 203.
Have been. The slit plate 210 of the sensor arm 211 is
Move between the light emitting and light receiving elements of the photo interrupter 212
The sensor arm 211 is connected to the measuring arm.
When the arm 203 is placed at the measurement position A, the slit plate
The slit of 210 passes the light of the photo interrupter 212.
The elastic member (not shown)
Pressing is stopped. The detailed description of the structure is omitted.
However, the measurement axis 204 to which the measurement arm 203 is attached is
A predetermined angle from the measurement position A with respect to the rotary cylinder 205
It is rotatable within the range, but at a predetermined angle
When it exceeds, it rotates with the rotary cylinder 205.
You.

Next, referring to FIG. 3 and FIG.
Lens blank after rough grinding using fixed unit 200
60 for measuring the Z value on the front surface 6a and the back surface 6b
explain about. 6 (a) to 6 (c) show measuring arms.
The positional relationship between the lens 203 and the lens blank 60 is shown in the y-axis direction in FIG.
FIG. 6D shows the lens blank 60 when viewed from the front.
FIG. 4 is a diagram showing a state of contact with each probe in the x direction in FIG. 3.
You. FIG. 6E shows a lens blank 60 between each probe.
FIG. 4 is a view of the state in which is arranged as viewed in the Z-axis direction in FIG. 3.

First, the Z value measuring motor 215 is driven.
To move measuring arm 203 from retracted position B to measured position A
Let it. At this time, the tip of the measuring arm 203 is
(E) As shown in FIG.
Or located above. Next, the lens holding unit 24
The held lens blank 60 (in this example, after rough grinding)
However, before the rough grinding), the first probe 201 and the second
Z-axis motor so that it is located
Activate the lens holding unit 24 to move the lens axis
Move in the direction. At this time, the lens blang 60
The stop position is set as a reference position a (see FIG. 6A).

Next, the Z-axis motor 108
A pulse signal to determine whether the lens blank 6 is at the reference position a.
Operates Z-axis motor 108 to move leftward in the figure
Let it. Counter 50 of microcomputer 600
In 3, the CPU 500 sends a pulse signal to the Z-axis motor 108.
And the number of pulses sent to the Z-axis motor 108 at the same time
Start measuring. The surface 60a of the lens blank 60 is
1 When it comes into contact with the tracing stylus 201, the measuring arm 203 moves to the left
(See FIG. 6B), so that the sensor arm 2
11 slit plate 210 is a photo interrupter 212
The optical path is blocked, and as a result, the detected signal is detected by the CPU.
500. The CPU 500 determines based on this detection signal.
The pulse signal sent to the Z-axis motor 108
Since the lens blank 60 is stopped, the lens blank 60 stops at the stop position b.
Stop. On the other hand, the counter 503 stops from the reference position a.
Continues sending from CPU 500 to Z-axis motor 108 until position b
The number of pulses (α) being measured is measured. In addition, FIG.
As shown, a table of the first tracing stylus 201 and the lens blank 60 is shown.
The contact point 60a _{1 in} contact with the surface 60a is at the surface side Z value measurement point.
is there. Next, from the CPU 500 to the Z-axis motor 108,
The lens blank 60 to the right in the figure.
Sends out a loose signal. With this pulse signal, the lens
The rank 60 moves to the right, and its back surface 60b is
Measuring arm 203 is tilted to the right by pressing fixed element 202
(See FIG. 4C), the light of the photointerrupter 212
Block the road. At this time, it is detected by the photo interrupter 212.
The detected signal is sent to the CPU 500 and the CPU 500
Stops the pulse signal sent to the Z-axis motor 108
The lens blank 60 stops at the stop position c.
You.

Stop at the stop position b at the counter 503
CPU 500 sent to Z-axis motor 108 to position c
The number of pulses (B) is measured. The communication shown in FIG.
The second tracing stylus 202 and the back surface 60 of the lens blank 60.
contacts 60b ₁ where b and are in contact is a rear side Z value measuring points.
In the present embodiment, the contact with the contact 60a ₁ described above 6
Bevel apex is located to be formed on the line connecting the 0b ₁
Become like

Next, based on the pulse numbers α and β measured by the counter 503 by the CPU 500, the lens blank 6
0 of the Z value Z _F and the rear surface of the Z value Z _R of the surface to calculate by the following equation. _{Z F = Zφ + δα Z R} = Z F + (C-δβ) where: Zfai the Z value at the reference point a, [delta] is the amount of movement of the lens blank 60 per pulse, C is stopped point c from the stop b
(C-δβ) is the lens thickness of the lens blank 60. In this manner, the CPU 500 determines
The Z value Z _F at the front and back surfaces 6a and 6b of the lens blank 60,
The Z _R is stored in the RAM 502.

Next, the first P-ROM 501 of the microcomputer 600 of the eyeglass lens processing machine having the above-described configuration is stored in the P-ROM 501.
The beveling process in which the fourth to fourth programs are stored and executed according to each program will be described. First, the first program and the second program will be described with reference to the flowchart shown in FIG.

<First Program> First, in FIG. 1, the chucking motor 9 is operated to hold the front and back surfaces 6 a and 6 b of the lens blank 6 before rough grinding between the lens holding shaft 7 and the lens support shaft 8. Then, the elliptical homer 20 is sandwiched between the other end of the lens support shaft 8 and the homer retainer 52.

Step S1 First, the operator decides which of the rough grinding and the specific calculation of the beveled curved surface is to be performed first, and selects the microcomputer 60 by using a selection key (not shown) on the operation panel 610.
0 is input to the CPU 500. In this example, rough grinding is performed first.

Step S2 Next, the diamond wheel 1 is rotated at a high speed, and the lens holding unit 24 is moved by the Z-axis motor 108 so that the lens blank 6 is positioned on the rough grinding surface 1b of the diamond wheel 1. Thereafter, the Y-axis motor 49
Is operated to lower the elevating table 44 so that the lens blank 6 is pressed against the diamond wheel 1.
While the lens shafts 7 and 8 are rotated clockwise and counterclockwise so that the contour shape of the shaper approximates the contour shape of the homer 20, the peripheral edge thereof is roughly ground. This rough grinding is completed in a state in which the shaving allowance at the time of beveling is divided into the contour shape of the spectacle lens to be finally finished.

Step S3 When the rough grinding is completed, the aforementioned rθ measuring means 300
Is used to measure the rθ value of the contour of the roughly ground lens blank 60. The measurement result of the rθ value is stored in the RAM 502 of the microcomputer 600 (rθ storage means). The CPU 500 reads out the stored rθ value from the RAM 502 and determines the measurement point of the Z value in the next step (measurement position determining means) according to the program stored in the P-ROM 501. The method of determining the measurement point of the Z value in the first program is as follows: r ₀ θ ₀ , r ₉₀ θ located at angles obtained by dividing the circumferential direction around the reference point (lens axis) into four.
₉₀ , r ₁₈₀ θ ₁₈₀ , and r ₂₇₀ θ ₂₇₀ are measurement points θ ₀ , θ ₉₀ , θ ₁₈₀ , and θ ₂₇₀ of the Z value. In this example, θ ₀ is the reference angle.

Step S4 The Z value at the front and back surfaces of each measurement point determined in this way is measured by the Z value measuring means 200 described above. First, the measurement arm 203 of the Z-axis measurement unit 200 at the retreat position B is moved to the measurement position A by operating the pulse motor 207, and the first tracing stylus 301 of the measurement arm 303 is moved.
The lens blank 60 is positioned at a reference point between
Place. The arrangement of the lens blank 60 is such that the Y-axis motor 49 is operated to raise the lens holding unit 24, and then the Z-axis motor 108 is operated so that the lens blank 60 reaches above the reference position a shown in FIG. Then, the Z-axis motor 108 is stopped, and the Y-axis motor 4
9 is operated to lower the lens holding unit 24 to a predetermined position shown in FIG. As described above, the lens blank 6 is moved from the first tracing stylus 101 to the second tracing stylus 20.
After the lens blank 60 has been placed at the reference position a, the first point r ₀ θ ₀ (θ ₀ is the reference angle) of the lens blank 60 determined in the above-described step is determined by the first tracing stylus 201 and the second tracing stylus 202. The CPU 500 sends a pulse signal to the lens motor 13 to rotate the lens blank 60 so that the lens blank 60 is positioned between the lens blanks (see FIG. 6E). Then, the lens blank 60 is moved in the Z-axis direction, and the surface thereof is brought into contact with the first tracing stylus 201. Contacts 60a ₁ of the first surface 60a of the feeler 201 and the lens blank 60 at this time is the measurement point of the surface 60a at the measurement point _{r 0 θ 0} (see FIG. 6 (d)).
Then, the back surface 60b of the lens blank 60 is
The Z-axis motor 108 is operated so as to come into contact with 02. Contacts 60b ₁ of the second measuring element 202 and the back surface 60b at this time is the measurement point of the back surface 60b. In this way, the Z values Z ₁ and Z ₂ on the front surface and the back surface at the peripheral portion r ₀ θ ₀ of the lens blank 60 are measured, and the measurement results are stored in the RAM 502. Then, the lens motor 13
Is operated to rotate the lens blank 60, and the other measurement points r ₉₀ θ ₉₀ , r ₁₈₀ θ ₁₈₀ , r ₂₇₀ θ
_{In step 270} , similarly, the Z values on the front and back surfaces are measured (Z value measuring means) and stored in the RAM 502. This gives R
As shown in Table 1 below, the AM 502 stores the Z value on the front surface and the back surface at each measurement point.

[0038]

[Table 1]

Next, in the CPU 500, the RAM 502
, The front surface Z value and the back surface Z value at each measurement point are read out, the difference between the front surface Z value and the back surface Z value is calculated, and the lens thickness at each measurement point is obtained as shown in Table 2 below.

[0040]

[Table 2]

Step S5 After determining the lens thickness at each measurement point in this way, the CP
It is recorded in the P-ROM 501 in U500.
A bevel vertex position at each measurement point is set (bevel vertex position determination means) according to a bevel vertex position setting program corresponding to the lens thickness. The criteria for this program are as shown in Table 3 below.

[0042]

[Table 3]

The bevel vertices thus set correspond to the surface 60a of the lens blank 60 shown in FIG.
It is located on the line connecting the contact point 60b ₁ contacts 60a ₁ and the back 60b of.

Step S6 : The Z of the bevel apex position set based on the above-described determination criteria
The value is calculated from the Z values of the front and back surfaces as shown in Table 4 below (first calculating means).

[0045]

[Table 4]

Step S7 After the bevel apex Z value at each measurement point is obtained in this manner, the rθ value of each measurement point is converted to XY coordinates as follows for convenience. r ₀ θ ₀ → (X ₀ , Y ₀ ), r ₉₀ θ ₉₀ → (X ₉₀ , Y ₉₀ ) r ₁₈₀ θ ₁₈₀ → (X ₁₈₀ , Y ₁₈₀ ) r ₂₇₀ θ ₂₇₀ → (X ₂₇₀ , Y _270,) then bevel curvature bevel curved surface that contains these bevel top radius _{R 1} and the bevel curvature center point _{P 1 (X Q, Y Q} , Z
_Q ) is obtained as a solution of the following equation (1).

[0047]

(1) | (X_Q-X₀)²+ (Y_Q-Y₀)²+ (Z_Q-Z₀)²= R₁ ²  | (X_Q-X₉₀)²+ (Y_Q-Y₉₀)²+ (Z_Q-Z₉₀)²= R₁ ²  | (X_Q-X₁₈₀)²+ (Y_Q-Y₁₈₀)²+ (Z_Q-Z₁₈₀)²  = R₁ ²  | (X_Q-X₂₇₀)²+ (Y_Q-Y₂₇₀)²+ (Z_Q-Z₂₇₀)²  = R₁ ²

The bevel curvature center P thus calculated
FIG. 8 schematically shows the relationship between ₁ and each measurement point. Thus bevel radius of curvature R ₁ and bevel curvature center point P
By calculating ₁ ( _XQ , _YQ , _ZQ ), the beveled curved surface is specified (second calculating means).

Step S12 Next, it is determined whether or not rough grinding has been completed before the above-described specific calculation of the beveled curved surface. In this example, since rough grinding has been completed, beveling is performed next.

Step S13 Next, the peripheral surface of the lens blank 60 is beveled so that the bevel apex is located on the bevel curved surface specified in this manner. First, the lens blanks 60 held by the lens holding unit 24 is located at the reference point of the Z value measuring unit 200, it is moved by operating the Z-axis motor 108 on the V-shaped groove 1a ₁ of the diamond wheel 1.
At this time, the outer peripheral side surface 60d and the S ₁ point of intersection of the bevel surface S of the lens blank 60 has been stopped on the V-shaped groove 1a ₁ as shown in FIG. 9 is located on the apex of the V-shaped groove 1a _1. Then, by operating the Y-axis motor 49, lowers the lens holding unit 24, a V-shaped groove 1a ₁ of the diamond wheel 1 during high-speed rotation, the lens blank 60
Press the outer peripheral side surface 60d. Next, the lens motor 1
3 to rotate the lens blank 60, and
At a predetermined angle θ of the lens blank 60, the lens holding unit 24 is set so that the bevel apex has a predetermined Z value.
Is moved in the lens axis direction by the Z-axis motor 108 to bevel the entire circumference of the peripheral side surface of the lens blank 60. Thus, the lens blank 60
The bevel apex obtained by performing the beveling on the outer peripheral side surface 60d is located on the beveled curved surface obtained as a result of calculation by the CPU 500.

Thus, in the eyeglass lens processing machine and the processing method according to the present embodiment, four predetermined bevel apex positions based on the lens thickness are set on the outer peripheral side surface 60d of the lens blank 60 in the calculation process. Since the beveled surface including the bevel apex is specified, the beveled surface can be set at a desired position on the outer peripheral side surface 60d of the lens blank 60 without depending on the front and back curves or the lens axis of the lens blank 60. . In addition, since the bevel apex position is set based on the table of the P-ROM 501 shown in Table 3, the spectacle lens can be attached to the frame rim in an excellent aesthetic sense.

In this embodiment, the measurement point for measuring the Z value is selected at a location where the circumference around the reference point is divided into four parts. However, the division is not limited to four parts, but may be performed at four or more parts. I just want it. In addition to the method of dividing the circumference at a predetermined ratio in this way, when the contour specified by the rθ value is surrounded so as to be in contact with the rectangle, the contact point between the contour and the rectangle is selected as a measurement point. Is also good. Also, lens blank 6
If the shape of 0 is not an ellipse as in this example, but is, for example, generally a so-called "blink" type, when measuring the Z value, it may be necessary to move the measuring arm 203 in the Z-axis direction, In such a case, the Z value measuring means 200 may be provided with a mechanism that allows the measurement arm to move in the Z-axis direction. Further, the criterion for determining the bevel apex position according to the lens thickness in step S5 is not limited to Table 3 described above, but may be appropriately determined according to various design specifications.

<Second Program> Next, a description will be given of a spectacle lens processing machine and a processing method for performing beveling according to the second program stored in the P-ROM 501. The difference between the second program and the first program described above lies in the procedure for selecting the Z-value measurement point and the procedure for specifying the beveled surface in the CPU 500.
The other steps are the same as in the beveling processing of the first program, and thus the description is omitted. In FIG. 7, the second program uses three points instead of four when measuring points of the Z value are selected based on the rθ value. These three points are peripheral portions at angles θ ₀ , θ ₁₂₀ , and θ _{240 obtained} by dividing the circumference around the reference point into three.

Step S8, Step S9, Step S10 Measurement of the Z values of the front and back surfaces at this measurement point, and the Z values of the obtained front and back surfaces.
The means for setting the bevel apex position based on the values and calculating the Z values Z ₀ , Z ₁₂₀ and Z ₂₄₀ of these bevel apex positions are steps S4 to S4 of the first program in FIG.
Same as 6.

Step S11 Next, when specifying the bevel surface based on the Z values Z ₀ , Z ₁₂₀ , and Z ₂₄₀ of the bevel apex, the bevel curvature radius R ₂ is previously stored in the RAM 502 by key input of the operation panel 610 shown in FIG. The bevel radius of curvature R is read out from the RAM 502, and the bevel radius of curvature R and
A beveled surface is specified by the Z values Z ₀ , Z ₁₂₀ , and Z _{240 of the} bevel apex. That is, the bevel curvature radius R ₂
Since is known, the bevel curvature center point P ₂ (X _P , Y _P , Z _P ) necessary for specifying the bevel surface is obtained as a solution of the following equation (2).

[0056]

(X)_P-X₀)²+ (Y_P-Y₀)²+ (Z_P-Z₀)²= R₂ ²  (X_P-X₁₂₀)²+ (Y_P-Y₁₂₀)²+ (Z_P-Z₁₂₀)²  = R₂ ²  (X_P-X₂₄₀)²+ (Y_P-Y₂₄₀)²+ (Z_P-Z₂₄₀)²  = R₂ ²

After the bevel curved surface is specified in this manner, the lens blank 6 is
The procedure of performing the beveling on the outer peripheral side surface of No. 0 is the same as the first program. As in this second program, three Z
When the bevel curved surface is specified based on the value measurement point and the known bevel curvature radius R, the beveled spectacle lens is smoothly and easily fitted to the inner peripheral surface of the rim of the spectacle frame. Can be. As a result, it is possible to prevent the occurrence of residual stress in the spectacle lens.

The input of the bevel radius of curvature R to the RAM 502 was performed by a key switch on the operation panel 610. Alternatively, the lens blank 6
The Z value at a predetermined position on the front and back surfaces of the zero is measured, the curvature of the front and back surfaces is calculated from the measured Z values, the bevel curvature radius R is calculated based on this curvature, and the calculation result is stored in the RAM 502.
May be stored. The details will be described below.

First, four Z-value measurement points are determined based on the rθ value by, for example, the procedure described in the first program, and the Z-values on the front and back surfaces of these measurement points are measured by the Z-value measuring means 200. The front surface curvature Rf and the back surface curvature Rb are calculated from the obtained Z values of the front and back surfaces. These surface curvature radii R
The method of calculating f and the back surface curvature radius Rb may be the same as the method of calculating the bevel curvature radius from the bevel vertex coordinates in the first program. Next, the surface curve value Rcf and the back surface curve Rcb are obtained from the surface curvature radius Rf and the back surface curvature radius Rb thus obtained. still,
These curvature radii and curve values have the following relationship. Rcf = 523 / Rf Rcb = 523 / Rb

Next, based on the front surface curve value Rcf and the rear surface curve value Rcb, the bevel curvature radius R is obtained through the following determination procedure. First, whether the lens blank is a minus power lens or a plus power lens is determined based on the obtained front surface curve value Rcf and back surface curve value Rcb. This determination is made based on the following equation. Rcf ≦ Rcb → Minus power Rcf> Rcb → Minus power First, the case where the lens is a minus lens as a result of this determination will be described first. First, a temporary bevel curve value Rif is obtained from the surface curve value Rcf based on Table 5.

[0061]

[Table 5]

Next, the final bevel curve value Ry is determined by the following formula using the obtained temporary bevel curve value. Temporal bevel curve value Rif > Back surface curve value Rcb

[0063]

(Equation 3)

In the case of the provisional bevel curve value Rif <the back surface curve value Rcb, the bevel curve value Ry = the provisional bevel curve value Rif In this manner, the bevel curve value Ry is determined by selecting one of the expressions. Next, the bevel curvature radius R is obtained from the following equation from the obtained bevel curve value Ry. R = 523 / Ry

The above is the method of calculating the bevel radius of curvature R of the minus power lens. Next, the method of calculating the bevel radius of curvature R of the plus power lens will be described. First, a temporary bevel curve value Rif is obtained by the following equation. Temporary bevel curve Rif = 1.05 × (front surface curve value Rcf + back surface curve value Rcb) Next, a bevel curve value Ry is obtained from the obtained temporary bevel curve value Rif based on the following determination. Front surface curve value Rcf> Temporary bevel curve value Rif> Back surface curve value Rcb → Bevel curve value Ry = Temporary bevel curve value Rif Temporary bevel curve value Rif > Surface curve value Rcf → Bevel curve value Ry = Surface curve value Rcf When bevel curve value Rif ≦ backside curve value Rcb

[0066]

(Equation 4)

The bevel curve value R obtained as described above
The bevel curvature radius R is obtained from y using the following equation. R = 523 / Ry The above is the calculation method of the bevel radius of curvature R in the case of a plus power lens.

As described above, the bevel curvature radius R is calculated in the CPU 500, the calculation result is stored in the RAM 502, and after the step 11 for specifying the beveled curved surface, the beveling in the second program step 13 described above is performed. If executed in a similar manner, the same effect can be obtained.

<Third Program> Next, a spectacle lens processing machine and a processing method for performing beveling according to a third program stored in the P-ROM 501 will be described with reference to FIG. This third program determines whether the lens blank 60 has a minus power or a plus power, and based on the determination result, determines measurement points of the Z value so that the bevel apex can be formed at an optimum position. The center of the bevel curvature is determined from the Z value of the bevel apex calculated from the Z values of the front and back surfaces and the bevel curvature radius R stored in the RAM 502 to specify the bevel curved surface. The details will be described below. Steps S6 and S11 in FIG. 10 shift to steps S7 and S12 in FIG. 11, respectively.

First, after going through the first and second steps in the same manner as the above-mentioned first and second programs, the rθ measuring means uses the rθ of the roughly ground lens blank 60 having the shape shown in FIG. The value is measured and stored in the RAM 502.

Step S3 Next, the CPU 500 reads the rθ value from the RAM 502, and stores the rθ value on the vertical axis shown in FIG.
Expressed in coordinates with the angle θ on the horizontal axis. The moving radius r and the angle θ represented by these coordinates are the rθ function. Next, the extreme value of r is determined, and the extreme values r _A θ _{A to} r _F θ _F are determined as the Z value measurement points.

Step S4 Next, the Z value on each of the front and back surfaces of the measurement points r _A θ _{A to} r _F θ _F is measured using the Z value measuring means 200 (FIG. 3).

Step S5 From the Z values of the front and back surfaces at each measurement point obtained by the Z value measuring means 200, the front surface curvature radius Rf, the back surface curvature radius Rb, and the front surface curvature radius Rb are calculated.
f and the back surface curve value Rcf from the back surface curvature radius Rb
And the back curve value Rcb are sequentially calculated. From the Z values of the front and back surfaces, a front surface curve value Rcf and a rear surface curve value Rcb are obtained.
Is calculated in the second program described above.
The same calculation method as described in the process of obtaining the bevel curve value from the measurement result of the Z value is used. Next, based on the obtained front surface curve value Rcf and back surface curve value Rcb, it is determined whether the lens blank 60 has a minus power or a plus power according to the following criteria. Rcf ≦ Rcb → minus power Rcf> Rcb → plus power After determining whether the lens blank 70 is a minus power or a plus power, the procedure differs depending on the plus power and the minus power. First, the case of a minus frequency will be described.

If it is determined in step S6 that the frequency is minus, the two extreme values at which the distance from an arbitrary extreme value point to another extreme value point among the extreme values of r obtained by the rθ measuring means are maximum are obtained. Points are selected as first and second measurement points. Figure 12 (a) to indicate the first and second measurement points in the lens blank shape _{r A} theta _A and _{r E} theta
_E. Then, each on either side of the line that runs on the first measurement point _{r A} theta _A second measurement point _{r E} theta _E, the minimum value _{r B} theta _B and _{r F} theta _F positioned respectively, third measurement The point and the fourth measurement point are determined.

[0075] Step S7 then these measurement points _{r A θ A, r E θ} E, r
Each bevel apex Z value of _{B θ B, r F θ F} , Z A, Z E, Z
_B, and calculated by the same method as the first program described above the Z _F.

Step S8 Next, the obtained bevel vertex Z value, Z _A , Z _E , Z _B , Z
_F and the bevel radius of curvature R stored in the RAM 502
₄ , the bevel center of curvature P ₃ (X _S , Y _S , Z _S )
Is calculated as the solution of the following equation (5).

[0077]

(X)_S-X_A)²+ (Y₃-Y_A)²+ (Z₃-Z_A)²  = (X_S-X_E)²+ (Y_S-Y_E)²+ (Z_S-Z_E)²  (X_S-X_B)²+ (Y_S-Y_B)²+ (Z_S-Z_B)²= R₄ ²  (X_S-X_F)²+ (Y_S-Y_F)²+ (Z_S-Z_F)²= R₄ ²

The bevel curvature center P calculated as described above
FIG. 13 schematically shows the relationship between No. ₃ and each bevel apex position (Z value). As shown in FIG. 13, the bevel curvature center P
_Although the distances from ₃ to the bevel apex positions Z _A and Z _E are the same, these bevel apex positions Z _A and Z _E are not always located on the bevel curved surface. On the other hand, the bevel curvature center _{P 3,} the bevel apex position _Z B, the distance of each to _{Z F} are both equal to the bevel radius of curvature _{R 4.} Note that, in this solution as well, the coordinates are converted from the rθ coordinates to the XY coordinates as in the first program. After specifying the beveled surface in this manner, steps S9 and S13 are performed similarly to the first program.
If the beveling is performed sequentially after the above, suitable beveling of the minus lens can be performed.

Step S10 Next, a case where it is determined to be a plus frequency will be described. r
Among the local maxima, the value of r is large in three places, r _A θ _A ,
Select the measurement point _{r C θ C, r F θ} F, calculated lens thickness shown in Table 6 below from the Z value of the front and back surfaces at these measurement points, setting the bevel apex position corresponding to the lens thickness I do.
The calculation of the lens thickness and the setting of the bevel apex position are the first.
It is the same means as a program.

[0080]

[Table 6]

Step S11 The method of calculating the bevel apex Z value from the respective Z values of the front and back surfaces at this measurement point is the same as in the first program. Table 7 below
Shows the values obtained in this calculation process.

[0082]

[Table 7]

Step S12 Next, the obtained bevel vertex Z values, Z _A , Z _C , and Z _E are obtained.
The bevel curvature center P ₄ (X _R , Y _R , Z _R ) is calculated from the bevel curvature radius R ₃ stored in the RAM 502 as a solution of the following equation (6).

[0084]

(X)_R-X_A)²+ (Y_R-Y_A)²+ (Z_R-Z_A)²= R₃ ²  (X_R-X_C)²+ (Y_R-Y_C)²+ (Z_R-Z_C)²= R₃ ²  (X_R-X_E)²+ (Y_R-Y_E)²+ (Z_R-Z_E)²= R₃ ²

The bevel curvature center P calculated as described above
FIG. 14 schematically shows the relationship between No. ₄ and each bevel apex position (Z value). As shown in FIG. 14, the bevel curvature center P
The distances from ₃ to the bevel apex positions Z _A , Z _C , and Z _E are all equal to the bevel radius of curvature R ₄ . In this solution, as in the first program, rθ coordinates are converted to XY coordinates for convenience. After specifying the beveled surface in this manner, steps S9 and S9 are performed similarly to the procedure of the first program.
By performing the beveling process sequentially through the steps 13, it is possible to perform a suitable beveling process on the positive power lens.

<Fourth Program> This fourth program is a program for measuring Z values,
If the lens thickness of the measurement point not adopted in the calculation for specifying the beveled surface is the smallest of all the measurement points,
Suitable beveling becomes possible. The fourth program will be described with reference to an example of a procedure determined to be positive in the third program. In the above-described operation, adopted measuring points to calculate the bevel vertex Z value _{r A θ A} ~r _{F θ r} in _{F A θ A, r C θ} C, r
_E θ _E only. In this case, the measurement points r _B θ _B and r _D
Although θ _D and r _F θ _F are not employed in the calculation, these measurement points r _B θ _B , r _D θ _D and r _F θ _F are also r _A θ _A , r
First, the lens thickness and the bevel apex Z value are calculated by the same method as that for calculating the lens thickness of _C θ _C and r _E θ _E. Measurement points r _B θ _B and r _D θ _D and r _F thus obtained
theta lens thickness of _{F, Z 10,} Z ₁₁ and a _{Z 12,} lens thickness of the other measuring points _{r A θ A, r C θ} C, r E θ E Z 7, Z
₈ compares the _{Z 9,} as a result, the lens thickness _{Z 11} measuring points _{r D} theta _D is assumed to be minimal. In this case, the measurement point r
_{Since D} θ _D is not employed in the calculation process, it is assumed that the bevel vertex of this measurement point θ _B is not located on the bevel curved surface specified based on the measurement points θ _A , θ _C , and θ _E. As described above, if a predetermined bevel apex is not formed at the measurement point r _D θ _D where the lens thickness is minimum, there is a possibility that breakage may occur at that portion. Therefore, the measurement points r _A θ _A , r _C θ _C , r
_After the bevel curved surface is specified based on _E θ _E , when the Z-axis motor 108 is operated to move the lens blank 60 onto the bevel groove 1 a ₁ of the diamond wheel 1, the specified bevel curved surface has θ Move so that the bevel vertex of _B is included. If the beveling is performed in such a positional relationship, a bevel vertex at a predetermined position can be formed at a portion on the peripheral side surface where the lens thickness is minimum.

The lens blank having the positive power of the third program has been described above as an example. However, even in the case of the negative power of the third program, the measurement value which is not subjected to the calculation among the measurement points at which the Z value is measured is also used. Since there is a point, when the lens thickness becomes minimum at the measurement points not used for these calculations, the same effect can be obtained by performing beveling according to the above-described procedure. Further, in the first and second programs shown in FIG. 7, even when the lens thickness of the measurement point not subjected to the calculation among the measurement points for which the Z value is measured becomes the minimum, the beveling is performed according to the above-described procedure. A similar effect can be obtained by doing so.

Next, a modified example common to the above-described first to third programs will be described below. First, the measurement of the Z value
Although performed after rough grinding, it may be performed before rough grinding. or,
When the Z value is measured, it is preferable to measure the top of the bevel portion as in the above-described embodiment, but it may be the inner peripheral side or the outer peripheral side of the top. When the Z value is measured before the rough grinding as described above, the rough grinding and the beveling may be sequentially performed after specifying the beveled curved surface. next,
The method of inputting the rθ value to the RAM 502 of the microcomputer 600 is based on the input from the above-described rθ value measuring means,
In addition to the input using the key switches on the operation panel, a measurement value from the frame shape measuring device may be input. This frame shape measuring device moves the tracing stylus over the entire periphery of the rim of the rim in a state in which the tracing stylus is in contact with the inner periphery of the rim of the spectacle frame, measures the amount of movement, and obtains an rθ value. Is measured. Further, when the rθ value is measured, the roughed lens blank is measured, but the rθ value of the homer may be measured instead of the lens blank. Furthermore,
Instead of using the rθ measuring means exemplified in the above-described embodiment, for example, the change amount of the moving radius r may be detected by measuring the rotation angle of the slide shaft 25 with a potentiometer. Further, as the rθ storage means, a magnetic recording medium such as a floppy disk separately provided outside may be used in addition to the RAM 502 of the microcomputer 600. or,
The reference point of the moving radius R may be another position as long as the position can be specified without being the axis of the lens axis. Further, although the Z axis coincides with the axis of the lens axis, it does not have to coincide, and may be substantially parallel to the lens axis.

[0089]

As described above, according to the eyeglass lens processing machine and the processing method according to the first and third inventions, the measurement
Rθ value stored in the rθ storage means by the position determining means
The read, the r in the maximum value of r of the function of this rθ value
Search for the three local maxima in descending order of the values, and find these maxima
Of the lens blank at three angles θ corresponding to
Three measurement points of the Z value of the portion are determined, and the bevel vertex position is set between the front surface measurement point and the back surface measurement point on the periphery of the lens blank by the bevel vertex position setting means. Calculating the coordinate value of the bevel vertex,
Since the beveled surface is specified based on the coordinate values of the bevel vertices, the peripheral portion of the spectacle lens can be obtained with less measurement point data.
Beveled in a well-balanced manner all around
it can.

Further , the spectacle glasses according to the second and fourth inventions.
According to the lens processing machine and the processing method,
From the extremum of the rθ function, any extremal point
The two extreme points where the distance to the value point is the largest are
Select the two measurement points and divide the two extreme points
The two extreme points located on each side of the line are
4 was determined as the measurement point. Also, the second calculating means
, Based on the coordinate value of the bevel apex position
When calculating the coordinates of the center of curvature of the surface,
Article that the distance from the heart to the first and second are equal to each other
And the distance from the center of the bevel curvature to the third and fourth
The bevel radius of curvature of the bevel surface under the condition
The bevel curvature is calculated and specified. In this way,
Identify the beveled surface and apply beveling to the spectacle lens
When manufactured, the outer peripheral side of the spectacle lens of minus power
Gen tops can be formed in a well-balanced manner all around
it can. This is for the following reason. First, minus degree
The number of spectacle lenses is generally small at r,
Is thin and the lens thickness is thick where r is long
You. Therefore, at the third and fourth measurement points where r is short,
The distance from the center of curvature to bevel radius of curvature R
In the place where the lens thickness is thin,
Can be formed. In addition, r is long and the edge thickness is large.
At the first and second measurement points, the distance from the center of the bevel curvature
Are equal, so the bevel apex positions balanced with each other
Can be

[Brief description of the drawings]

FIG. 1 is a perspective view showing main components showing an embodiment of an eyeglass lens processing machine according to the present invention.

FIG. 2 is a side view of the rθ measuring means.

FIG. 3 is a perspective view of a Z value measuring unit.

FIG. 4 is an electric block diagram.

FIG. 5 is a conceptual diagram for calculating a Zθ value from a distance between axes.

FIGS. 6A to 6E are diagrams illustrating a relationship between a measurement arm of a Z value measurement unit and a lens blank.

FIG. 7 is a flowchart of first and second programs.

FIG. 8 is a diagram illustrating a relationship between a bevel curvature center and a bevel apex position.

FIG. 9 is a diagram showing a position of a lens blank on a diamond wheel immediately before starting beveling.

FIG. 10 is a diagram showing the first stage of the flowchart of the third program.

FIG. 11 is a diagram illustrating the second half of the flowchart of the third program.

FIGS. 12A and 12B are a diagram showing a lens blank used when executing a third program, and a diagram showing rθ coordinates used in the calculation of the third program.

FIG. 13 is a diagram illustrating a relationship between a bevel curvature center and a bevel apex position.

FIG. 14 is a diagram illustrating a relationship between a bevel curvature center and a bevel apex position.

[Explanation of symbols]

1 ... diamond wheel , 6 ... lens blank , 7 ...
Lens holding shaft , 8 : Lens support shaft , 9 : Chucking motor , 13 : Lens motor , 24 : Lens holding unit , 29 : Moving means , 49 : Y-axis motor , 60 : Lens blank , 108 : Z-axis motor , 200 ... Z value measuring means , 215 ... Z value measuring motor , 300 ... rθ measuring means.

──────────────────────────────────────────────────続 き Continuation of front page (56) References JP-A-59-156657 (JP, A) JP-A-1-177953 (JP, A) JP-A-62-9858 (JP, A) JP-A-2- 212058 (JP, A) (58) Field surveyed (Int. Cl. ⁶ , DB name) B24B 9/14

Claims (4)

(57) [Claims] 1. A lens device comprising: a pair of lens shafts for sandwiching the front and back surfaces of a lens blank; and a driving device for rotating the lens shafts, the direction being movably along the lens axis direction and orthogonal to the lens axis. A lens holding unit that is rotatably supported on the lens, moving means for reciprocating the lens holding unit in the lens axis direction, and a rough ground surface for grinding a peripheral portion of a lens blank held between the pair of lens shafts And a rotating grindstone having a beveled grinding surface having a beveled groove formed on the surface thereof. After performing a rough grinding process to form a shape larger than the inner peripheral contour shape of the rim of the frame, the moving means moves the lens holding unit to perform rough grinding. A spectacle lens processing machine that presses a lens blank against a beveled grinding surface of a rotating grindstone to bevel the peripheral portion of the lens blank into a shape that can be fitted to an inner peripheral surface of a rim of the spectacle frame, wherein the pair of lenses A Z-axis that is coincident with or parallel to the axis of the axis, and three-dimensional coordinates defined by an rθ plane perpendicular to the Z-axis are set, and a contour similar and approximate to the inner peripheral contour shape of the rim of the spectacle frame. rθ value specifying the shape (r: radius vector from the reference point, theta: the rotation angle from the reference angle) reads rθ values stored as rθ storage means to said rθ storage means to be serial billion, this rθ value The value of r among the local maxima of the function
Search for the three maxima in descending order of
Peripheral edge of lens blank at corresponding three angles θ
Measuring position determining means for determining three Z value measuring points, Z value measuring means for measuring each of the front and rear Z values at the measuring points determined by the measuring position determining means, and a periphery of the lens blank In the unit, bevel vertex position setting means for setting a predetermined bevel vertex position between the front surface measurement point and the back surface measurement point, and the coordinate value of the set bevel vertex with the rθ value stored in the rθ storage means , Z obtained by the Z value measuring means
First calculating means for calculating from the value, coordinate values of each bevel vertex obtained by the first calculating means,
Half bevel curvature read from bevel curvature radius storage means
The second to specify the bevel curvature by calculating the center of curvature from the radius R
When processing the peripheral edge of the roughly ground lens blank into a shape that can be fitted to the inner peripheral surface of the rim of the spectacle frame, the peripheral edge of the lens blank is beveled by a rotary grindstone. Then, based on the calculation result obtained by the second calculating means, the moving means is operated to move the lens holding unit along the lens axis, so that the entire area of the outer peripheral side surface of the lens blank is A spectacle lens processing machine, wherein the beveling is performed such that a bevel apex position formed over the bevel is located on the beveled curved surface calculated by the second calculating means . 2. A pair of lens blanks for sandwiching the lower surface of the lens blank.
And a driving device for rotating the lens axis.
To move freely along the lens axis direction, and
Lens holder supported rotatably in the direction perpendicular to the axis
Unit and the lens holding unit
Moving means for reciprocating in a direction, and the pair of lens axes
Rough grinding that grinds the periphery of the pinched lens blank
Form a beveled grinding surface with a beveled surface and a beveled groove on the surface
And a rotating whetstone, which is pinched by the pair of lens axes.
The peripheral edge of the roughened lens blank
Press against the ground surface to remove the
Rough grinding to form a shape larger than the peripheral contour shape
Then, the lens holding unit is moved by the moving means.
Move the rough-ground lens blank to bevel
By pressing against the ground surface, the lens blank
Peripheral part can be fitted to the inner peripheral surface of the rim of the spectacle frame
In a spectacle lens processing machine for beveling a shape, three-dimensional coordinates defined by a Z-axis coinciding with or parallel to the axis of the pair of lens axes and an rθ plane perpendicular to the Z-axis
Is set to the inner peripheral contour shape of the rim of the eyeglass frame.
Rθ value specifying a similar and approximate contour shape (r: reference
Radius from the point, θ: rotation angle from the reference angle)
rθ storage means, and rθ value stored in the rθ storage means
And read any arbitrary extremum among the extremum points of the rθ value function.
The two extremes where the distance from the value point to the other extreme point is maximum
The points are determined as the first and second measurement points, and are located on both sides of a dividing line connecting the two extreme points.
Measuring two extreme points as third and fourth measurement points
Position determining means, and at a measurement point determined by the measurement position determining means,
Value measuring means for measuring the respective Z values of the front surface and the back surface, and the surface measurement point at the periphery of the lens blank.
A predetermined bevel vertex position between the measurement points on the back and back
Bevel vertex position setting means, and the rθ storage means
Obtained by the Z value measuring means and the rθ value stored by
A first calculating means for calculating from the Z value, and a center of the bevel curvature based on the coordinates of the bevel vertex position.
The distances to the first and second measurement points are equal to each other
Conditions and the third and fourth measurement points from the center of the bevel curvature
The curvature of the bevel surface under the condition that the distances are equal to each other
Calculate the center coordinate value, and further calculate the coordinate value of the bevel vertex
Calculate the bevel curvature radius based on the bevel curvature
A second arithmetic means, wherein the peripheral portion of the roughly ground lens blank is
When processing into a shape that can be fitted to the inner peripheral surface of the rim, the peripheral edge of the lens blank is
After pressing, the calculation result obtained by the second calculation means
The moving means is operated based on the
By moving the lens along the lens axis,
A lens formed over the entire area in front of the outer periphery of the lens blank
The bevel tune whose bean vertex position is calculated by the second calculating means
A spectacle lens processing machine characterized by performing beveling so as to be positioned on a surface . 3. A pair of holding the front and back surfaces of a lens blank.
And a driving device for rotating the lens axis.
To move freely along the lens axis direction, and
Lens holder supported rotatably in the direction perpendicular to the axis
Unit and the lens holding unit
Moving means for reciprocating in a direction, and the pair of lens axes
Rough grinding that grinds the periphery of the pinched lens blank
Form a beveled grinding surface with a beveled surface and a beveled groove on the surface
And a rotating whetstone, which is pinched by the pair of lens axes.
The peripheral edge of the roughened lens blank
Press against the ground surface to remove the
Rough grinding to form a shape larger than the peripheral contour shape
Then, the lens holding unit is moved by the moving means.
Move the rough-ground lens blank to bevel
By pressing against the ground surface, the lens blank
Peripheral part can be fitted to the inner peripheral surface of the rim of the spectacle frame
In the eyeglass lens processing method for beveling into a shape, three-dimensional coordinates defined by a Z-axis coinciding with or parallel to the axis of the pair of lens axes and an rθ plane perpendicular to the Z-axis.
Is set to the inner peripheral contour shape of the rim of the eyeglass frame.
Rθ value specifying a similar and repetitive contour shape (r: reference
Radius from the point, θ: rotation angle from the reference angle)
reading and rθ storing step, the rθ value stored in the rθ storage step,
The order of the largest value of r among the maximum values of r in the function of this rθ value
Are searched for three local maxima, and 3 maxima corresponding to these maxima are retrieved.
Of the Z value of the peripheral edge of the lens blank at the angle θ
A measurement position determination step of three positions determined fixed point, the measurement points determined by the measurement position determination step
Value measurement step for measuring each Z value of the front and back surfaces
And the surface measurement point at the periphery of the lens blank.
To set a predetermined bevel apex position between the
The step of setting the position of the bevel apex and the step of storing the coordinate values of the set bevel apex in the rθ storage step.
Value obtained by the r-value stored in the
Calculation step for calculating from the Z value obtained, and coordinate values of each bevel vertex obtained in the first calculation step
And the bevel read from the bevel curvature radius storage step
Calculate the center of curvature from the radius of curvature R to specify the bevel curvature
A second calculating step of performing the above-described operation, and
When processing into a shape that can be fitted to the inner peripheral surface of the rim, the peripheral edge of the lens blank is
After the pressing, the calculation result obtained in the second calculation step is obtained.
The moving means is actuated based on the result and the lens holding unit is operated.
By moving the knit along the lens axis,
Formed over the entire outer peripheral side surface of the lens blank.
Bevel vertex position calculated in the second calculation step
Execute beveling so that it is located on the beveled surface
An eyeglass lens processing method comprising: 4. A pair of lens blanks for holding the front and back surfaces of a lens blank.
And a driving device for rotating the lens axis.
To move freely along the lens axis direction, and
Lens holder supported rotatably in the direction perpendicular to the axis
Unit and the lens holding unit
Moving means for reciprocating in a direction, and the pair of lens axes
Rough grinding that grinds the periphery of the pinched lens blank
Form a beveled grinding surface with a beveled surface and a beveled groove on the surface
And a rotating whetstone, which is pinched by the pair of lens axes.
The peripheral edge of the roughened lens blank
Press against the ground surface to remove the
Rough grinding to form a shape larger than the peripheral contour shape
Then, the lens holding unit is moved by the moving means.
Move the rough-ground lens blank to bevel
By pressing against the ground surface, the lens blank
Peripheral part can be fitted to the inner peripheral surface of the rim of the spectacle frame
In the eyeglass lens processing method for beveling into a shape, three-dimensional coordinates defined by a Z-axis coinciding with or parallel to the axis of the pair of lens axes and an rθ plane perpendicular to the Z-axis.
Is set to the inner peripheral contour shape of the rim of the eyeglass frame.
Rθ value specifying a similar and approximate contour shape (r: reference
Radius from the point, θ: rotation angle from the reference angle)
reading and rθ storing step, the rθ value stored in the rθ storage step,
From the extremum points of the rθ value function,
The two extreme points where the distance to the extreme point is the maximum are defined as the first and the
It is determined as a second measurement point, and is located on each side of a dividing line connecting these two extreme points.
Measuring two extreme points as third and fourth measurement points
A position determination step, and a measurement point determined by the measurement position determination step.
Value measurement step for measuring each Z value of the front and back surfaces
And the surface measurement point at the periphery of the lens blank.
A predetermined bevel vertex position between the measurement points on the back and back
A bevel vertex position setting step, and the coordinate values of the set bevel vertex are stored in the rθ storage step.
The rθ value stored by the step and the Z value measurement step
A first calculation step of calculating from the obtained Z value, and determining the coordinates of the bevel vertex position from the bevel curvature center
The distances to the first and second measurement points are equal to each other
Conditions and the third and fourth measurement points from the center of the bevel curvature
The curvature of the bevel surface under the condition that the distances are equal to each other
Calculate the center coordinate value, and further calculate the coordinate value of the bevel vertex
Identify the bevel curvature by calculating the bevel radius of curvature
A second calculating step, wherein the peripheral edge of the roughly ground lens blank is
When processing into a shape that can be fitted to the inner peripheral surface of the rim, the peripheral edge of the lens blank is
After the pressing, the calculation result obtained in the second calculation step is obtained.
The moving means is actuated based on the result and the lens holding unit is operated.
By moving the knit along the lens axis,
Formed over the entire outer peripheral side surface of the lens blank.
The bevel vertex position is calculated in the above-mentioned knitting 2 calculation step.
Execute beveling so that it is located on the beveled surface
An eyeglass lens processing method comprising: