JPS58177256A - Lens periphery processing machine - Google Patents

Abstract

PURPOSE:To provide a machine to process the lens peripheries of a pair of glasses, which can be operated easily even by an operator with poor experience, by equipping the machine with an electric control means for automatic grinding into the optimum curve, whichever shape the lens has, through measurement of its edge thickness. CONSTITUTION:A head frame 4 is equipped with a chucking mechanism to hold a lens 5 for glasses and turn it, and is so constructed as movable both in the horizontal direction and in the lens's radial direction. One of the ends of a lens holder shaft 6 installed on this head frame 4 is coupled with a motor 8, and a ball piece 9 having a form copied from the rim contour of the frame of glasses is mounted on a lens receptacle shaft 7 at its one end so as to be moved vertically by a driver device 24. A coarse grinder 20 and a V-shaped grinder 21 are installed on the body frame 1 in such a way that their rotary shafts are positioned in parallel with the supplorting shaft 3. Near this grinder 20 is installed a sensor part 25 for automatic measurement of the edge thickness of the lens 5.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a lens periphery processing machine that can automatically form a bevel on the periphery of a spectacle lens.

In order to fit into the rim of an eyeglass frame, the periphery of the eyeglass lens is usually processed into a V-shape called a bevel. In this case, the procedure is to process the eyeglass lenses into the same shape as the rim of the eyeglass frame, and then attach a bevel.

As a premise, it is necessary to consider the relationship between the edge thickness of eyeglass lenses and the rim curve of eyeglass frames. That is, the edge thickness of eyeglass lenses varies depending on the following factors.

(1) Required lens power.

(2) Pressure shape determined by the rim shape of eyeglass frames.

(3) When the eyeglass lens is eccentrically chucked to the processing machine with respect to its optical center.

On the other hand, the rim curve of eyeglass frames is manufactured with a substantially constant curve due to manufacturing reasons. Therefore, it is necessary to add a bevel curve to the peripheral edge of the eyeglass lens to match the substantially constant rim curve of the eyeglass frame.

Therefore, conventionally, spectacle lenses have been processed as follows. In other words, for eyeglass lenses with relatively low power, the curve of the lens is the same as or close to the rim curve, so after making the head frame of the lens edge processing machine freely swingable in the horizontal direction, the eyeglass lens is It was processed so that the bevel was placed near the center of the edge thickness.

In addition, with high-power eyeglass lenses, the above method would result in a bevel curve that was far different from the rim curve of the eyeglass frame, so a cam was installed to restrict horizontal movement of the head frame to create a bevel curve that was close to the rim curve. . Moreover, this cam was troublesome to adjust its position every time a lens was added or replaced. Furthermore, when using this cam, the position where the curve will actually form on the eyeglass lens cannot be determined before processing, so the lens must be brought close to the grinding wheel to find the optimal horizontal position, and then the lens must be placed on the grinding wheel. I had to try it out. This work requires the most experience among the processing steps, and also requires a lot of time.

However, some eyeglass frames require a grooved edge instead of a bevel, and the same applies to cases where grooved curves are ground into eyeglass lenses.

An object of the present invention is to provide a lens peripheral edge processing machine that can automatically grind grinding curves such as bevels and groove edges to optimal positions.

The present invention will be fully explained below based on embodiments shown in the drawings.

1 to 5 show embodiments of the present invention.

A support shaft 3 is supported slidably in the horizontal direction (in the axial direction) on a support bearing 2 fixed to the main body frame 1, and a head frame 4 is rotatably supported on the shaft 3 (arrow A). Attach.

The head frame 4 is formed with a concave tube for chucking the eyeglass lens 5. A lens press shaft 6 and a lens holder shaft 7 are passed through the concave hole from both sides of the head frame 4, and a lens press shaft 7 is inserted into one end of the lens press shaft 6. A drive device 8 such as a motor for driving the shaft 6 in the axial direction is connected thereto, and the other end is provided with a rubber band for directly pressing the spectacle lens 5, although not shown in the figure.

- The lens holder has a pressure mold 9 shaped like the rim of an eyeglass frame attached to one end of the shaft 7, and this pressure mold 9 is replaceable, and the lens holder has a spectacle lens 5 attached to the other end of the shaft 1.
A rubber or the like (not shown) is provided to directly receive the water.

The lens holding shaft 6 and the lens holder have a shaft T which is a gear train 10a,
The lens holder is synchronously rotated by a pulse motor 10 for lens rotation via a transmission device such as a belt 10b (arrow B), and a reference plate 11 having a cutout is provided on the shaft 7 for initial device detection of lens rotation. A photointerrupter 12 is provided on the head frame 4 so as to be fixed and sandwich the reference plate 11.

In Figure 2, which shows the machine shown in Figure 1 from the rear,
The support shaft 3 passes through a linear portion 4a cut out to include the support shaft 3f on the rear side of the head frame 4, so that the support shaft 3 is moved along the support shaft 3 together with the head frame 4 in the horizontal direction (
A connecting member 13 movable in the direction of arrow C) is provided, and the other end of the connecting member 13 is connected to a pulse motor 1 for moving the head frame.
4 and an electromagnetic clutch 15, it is connected to a timing belt 1g that moves horizontally by a pulley 16 fixed to the shaft end of the clutch 15. The initial position of the head frame 4 in the horizontal direction is set by the projecting piece 18 provided at the end of the connecting member 13 shielding the photo interrupter 19 provided on the main body frame 1 from light.

A roughing grindstone 20 and a ■-shaped grindstone 21 for bevel processing are installed on the main body frame 1 so that their rotational axes are parallel to the support shaft 3.

The rotation of the grindstones 20 and 21 is driven by a motor (not shown). A press die receiver 22 having a curved surface having the same curvature as the grindstone 21 is provided on the main body frame 1 side to receive the press die 9. Although the pressure mold receiver 22 is not shown in FIG. 1, as shown in FIG. 4, a rack 223 is attached to the frame 220, and a gear 23 is engaged with the rack 223. The gear 23 is rotated by a pulse motor 24 for raising and lowering the upper mold, and thereby the mold receiver 22 is configured to move up and down (arrow D). The vertical height reference position of the pressure mold receiver 22 is added to the fixed guide 225 side, and the photo interrupter 224 is attached to the frame body 220 side.
Detected by light source. Also, whetstone 2
As shown in FIG. A light shielding member 251° and a spring 254 are provided in the middle part of the photointerrupter 252tl-HI, and the spectacle lens 5 which has been roughly rubbed is swung within the U-shaped part of the contact 250. , photo interrupter 252
It turns on and off.

Further, in order to rotate the head frame 4 around the support shaft 3, a wire 26 whose one end is fixed to the connecting member 13 is provided.
The wire 26 is hung on the pulley 27 on the tl-head frame 4 and bent horizontally, and the other end of the wire 26 is fixed to the movable member 2B which moves horizontally by the rotation of the screw 28.

The screw 28 is connected to a DC motor 31 via a gear 30. Since the head frame 4 is given a rotational force in the clockwise direction in FIG. 1 due to its own weight, the DC motor 3
1, gear 30, screw 2B, moving member 29, wire 26
Thus, a rotational force for rotating the head frame 4 to the left is obtained. In order to detect the rotational position of the head frame 4, an i-recorder 32 is fixed to the head frame 4, and a small pulley 32m is integrally provided on the rotation axis of the encoder 32, and this pulley 32m and pulley 13a are connected to each other. A string 32b is hung between them, and as a result, the encoder 32 rotates in accordance with the rotation of the head frame 4. Further, the initial position of the encoder 32 is the photo interrupter 4b attached to the nose frame 4.
It is detected by machining the base plate 13c added to the connecting member 13.

In this embodiment, the drive unit includes pulse motors 10 and 14.
, 24 are connected to photointerrupters 4b and 1 for position detection.
I am using 2.19.222.224.252,
This photointerrupter-4b, 12.19.222.
Instead of 224.252, other sensors or sensors such as limit switches can be used. Furthermore, it is also possible to achieve the same function by using a DC motor in place of the pulse motors 10 and 1424, and an encoder for detecting the position.

Next, the electric control device '1&:@5 used in conjunction with the apparatus shown in FIGS. 1 to 4 will be explained. Electrical control system [
50 is an input switch 51 for a curve value (represented by K as described later, and has a relationship of =52- with the radius R of this spherical surface when considered as a part of the spherical surface of the eyeglass frame).
a and a measurement start switch 51b; a predetermined program based on a flowchart to be described later and a horizontal reference position, the roughening grindstone 20, the ■-shaped grindstone 21, and the contactor 250 of the detection unit 25 on the casing; A first storage unit 52 that stores the distance as the number of drive pulses of the pulse motor 14; a control unit 53 that has an arithmetic function and controls each part according to a program stored in the first storage unit 52; and It has a second storage unit 54. The control s53 is connected to a pulse motor 10 for rotating eyeglass lenses via a pass line 55.
, a photo interrupter 12 that outputs a rotation reference signal for eyeglass lenses, and a pulse motor 14 for driving the head frame.
, a photointerrupter 19 that outputs a horizontal reference signal.
, a DC motor 31 that moves the head frame up and down,
Photointerrupter 4b that detects the reference position of the vertical movement of the head frame 4; encoder 32 that detects the amount of vertical movement of the eyeglass lens; grindstone rotation motor 56; photointerrupter as a sliding detector; vertical height detector of the 222 type receiver. and a photointerrupter 252 for measuring the edge thickness of eyeglass lenses.

Next, a flowchart (illustrated in FIG. 6) and other explanatory diagrams (FIGS. 7 to 12) defining the above-mentioned predetermined program
The operation of the device will be explained with reference to.

When the power switch (not shown) is turned on, the DC motor 31
rotates, the wire 26 is pulled to the left in FIG. 2, and as a result, the head frame 4 is lifted upward to a predetermined position.

In this state, the upper mold 9 and the unprocessed eyeglass lens 5 are chucked. The diameter and curve value (11) are entered into the keyboard section 51 using the input switch 51m (step 60 in FIG. 6), and the measurement start switch 51bi is turned on (step 61 in FIG. 6).

Then, the diameter and curve value are changed to the second
The driving pulse is stored in the memory circuit 54, and the driving pulse is inputted from the control unit 53 to the pulse motor 14 for moving the head frame. The pulse motor 14 rotates, and the protruding piece 18
passes through the photo-interrupter 19, and the photo-interrupter 19 generates a horizontal reference signal. When the control unit 53 receives the horizontal reference signal, it stops supplying drive pulses to the pulse motor 14 for moving the head frame.
Thereafter, pulses of an order corresponding to the distance of the roughening grindstone 201 from the horizontal reference position stored in the first storage section 52 are inputted to the pulse motor 14 for moving the head frame. Therefore, the unprocessed eyeglass lens 5 is polished by the rough grinding wheel 20.
It will come to a horizontal position corresponding to I7c. When the control unit 53 finishes inputting a predetermined number of pulses (2) to the pulse motor 14 for moving the rough grinding wheel 14, the control unit 53 controls the motor 5 for rotating the roughing grindstone 20.
6 and causes the motor 56 to rotate. Next, the DC motor 31 is rotated, the moving member 29 is advanced to the right in FIG. When placed on the grindstone 20 with a predetermined pressing force, the spectacle lens 5 is roughly rubbed. The control unit 53 also sends a signal to the eyeglass lens rotating pulse motor 10. Therefore, the unprocessed eyeglass lens 5 is roughly polished by the slowly rotating roughening grindstone 20. The end face of the unprocessed eyeglass lens 5 is ground so that it has approximately the same shape as the upper mold 9 that has been previously attached. The degree of this is adjusted by raising and lowering the mold receiver 22 using a pulse motor 24 for raising and lowering the mold. Near the end of roughing, the upper mold 8 comes into contact with the pressure mold receiver 22, the pressure mold receiver 22 is thereby rotated, and the closing rod 221 is brought into contact with the photointerrupter 2.
22 intermittently, and the end of the roughening is detected by the signal from the photo ink scrubber 222 obtained thereby (
At step 62 in FIG. 6), the control unit 53 enters the lens radius measurement step (step 63 in FIG. 6) and applies drive pulses to the eyeglass lens rotation pulse motor 10 until a rotation reference signal is obtained from the photointerrupter 12. send. When the rotation reference signal is obtained from the photointerrupter 12,
The control unit 53 performs a step of reading the rotation angle θ and the radius r (
Step 64) in FIG. 6 is entered. Glasses lens 5't-
When rotated, the head frame 4 moves up and down in response to changes in the radius r of the eyeglass lens 5. Therefore, the control unit 53 stores a value corresponding to the radius r of the eyeglass lens 50 obtained from the encoder 32 in the second storage circuit 54 in correspondence with the number of drive pulses sent to the eyeglass lens rotation pulse motor 10.
to be memorized. 1 pulse has L degrees Celsius glasses lens 5 is 1
If it is set to rotate by 1 degree, the radius r for each 1 degree is stored in correspondence with the rotation angle. When the eyeglass lens 5 rotates 360 degrees and the rotation reference signal is obtained again from the photointerrupter 12, 360 pieces of data are stored in the second storage circuit 54, and the step of reading the angle θ and the radius γ (the first Step 64) in Figure 6 is completed. The control unit 53 enters an extreme value detection step (step 65 in FIG. 6).

The control unit 53 sequentially reads out the values of the radius r from the second storage circuit 54 and finds the extreme value by comparing the previous and subsequent values. That is, as shown in FIG. 7, if the spectacle lens 5 after rough printing is considered as a circle for simplicity, the positions where the short axis and long sleeve intersect with the outer circumference, b, e, and d are extreme values. . That is, the second memory circuit 54 actually stores 0 to 3 as described above.
Data for 360 degrees is obtained for each degree over 60 degrees, but for the sake of simplicity, we assume that the data is obtained continuously, and if we show it all visually, it will be as shown in Figure 8. . In FIG. 8, the horizontal axis is the rotation angle (15) of the spectacle lens 5 from the rotation reference position, and the vertical axis is the radius γ of the spectacle lens 5. As is clear from FIG. 8, at point a when the tie angle is 0 and at point 0 when the rotation angle is π, the radius γ is the minimum value ra, rc4
The radius γ takes the maximum value rbzrd at point b when the rotation angle is 2 and at point d when the rotation angle step is π.

The positions of the extreme values, ie, points a to d, are stored in the second storage circuit 54. As is clear from FIG. 7, the extreme points a to d are the points where processing is performed at the apex of the hulling grindstone 20, and the radii ra to rd at these points indicate the true radius of the eyeglass lens 5.

When the extreme value detection step is completed, the control section 53 proceeds to step 66 in FIG. 6 and determines whether or not there is an extreme value. If the spectacle lens 5 is circular, there is no extreme value, so the rotation reference position is determined as the extreme value via step 6T in FIG. Once the extreme values have been determined for all shapes in this manner, a step (step 68 in FIG. 6) K of measuring the edge thickness of the eyeglass lens 5 at the extreme value is entered. That is, (16) the control unit 53 applies a drive pulse to the pulse motor 14 to move the head frame 4 in the horizontal direction at position 1 where the spectacle lens 5 enters the contact 250 of the detector 25.

Since the position of the contact 250 is at a constant distance from the horizontal reference position S, the control unit 53 determines the position of the contact from the distance from the horizontal reference position S stored in the first storage circuit 52 to the hulling grindstone 20. The head frame 4t is moved by the distance obtained by subtracting the distance up to 250. After that, the control section 53
sends a rotation signal to the pulse motor 24 to lower the head frame 4 and insert the spectacle lens 5 into the contact 250. The horizontal position of the lens at this time is set in advance and is called the edge thickness measurement reference position. Thereafter, a signal is sent to the pulse motor 10 for rotating the eyeglass lens so that the extreme value is located within the contact 250. In this example, since the rotation direction reference position corresponds to the extreme point a, the pulse motor 10 does not rotate. Note that the first memory circuit 52 includes:
Instead of storing the distance from the horizontal reference position S to the contactor 250, the distance from the hulling grindstone 20 to the detection unit 25'! ! !
Of course, it is also possible to store the position at .

FIG. 9 shows the lens in the edge thickness measurement reference position, and when a drive pulse is input to the pulse motor 14 to move the lens to the left, the contact 250 rotates and a signal is output from the photointerrupter 252. . Movement from the edge thickness measurement reference position at that time i】+ *Number of pulses (The control unit 53 counts up and down the drive pulses and constantly checks the number of drive pulses corresponding to the current position of the eyeglass lens 5. ) to read. Similarly, it moves to the right and the amount of movement from the edge thickness measurement reference position is 1. Read in number of pulses.

Taking this into account, the control unit 53# calculates the edge thickness aDi of the lens at point a by performing all calculations H-(+1 +It) from the previously stored distance H between the left and right end surfaces 25a and 25b of the contactor 250. The control unit 53 sends a signal to the pulse smoke 10, and sequentially inserts the other extreme points, point C, and point d into the contactor 250, and determines the edge thickness bD of the lens at point A, point C, and point d.

Find cD and aD.

Note that the distance between the edge thickness measurement reference position and the horizontal direction reference position S is stored in advance in the memory circuit 52, and it is stored in the memory circuit 52 in advance.
Then, the positions of both end faces of point a are calculated as M-], , M+], respectively. If this value '(a・L17, dL2 is set, the other points are bL+, bL2, ......, dL,
, dL2, and these data are stored in the storage circuit 54.
to be memorized.

Using FIG. 10 to visually explain the data obtained in this way, the horizontal axis shows the distance 1 from the horizontal reference position.
11! L is taken as the vertical axis and the rotation angle θ of the eyeglass lens is taken as 50,
For each point a, b, C, and d, the distances aL1, bIi, cLl, dLl, from the horizontal reference position S,
and aLl + taking into account the thickness of the eyeglass lens at each point.
JLD% bLl +bDXcL1 +cDx dLl
+dD(2)] By connecting the points corresponding to point a, point b, point C, and point d, a graph showing the edge of the eyeglass lens 5 can be obtained. The shaded area in Figure 9 is the edge thickness (a) of the eyeglass lens.
Points other than point B, point C, and point d are approximate), and the area within this shaded area is the area in which bevel curves can be added.

Next, the control unit 53 determines the average value of the radius γ over the entire circumference of the spectacle lens 5 determined previously (step 69 in FIG. 6).
At the same time, the curve value inputted prior to the measurement is read out from the storage circuit 52, and the radius Ri corresponding to the curve value is determined,
As shown in FIG. 11, the tangent at the intersection Q on the radius R with the average value rm@lLn of the radius r is determined (step 70 in FIG. 6). The slope of this tangent line becomes the approximate straight line (step 71 in FIG. 6). In the finishing start step (step 27B in FIG. 6), which will be described later, the spectacle lens 5 is rotated and given a bevel curve while following this straight line according to the change in radius. Approximate tracing straight line shown in FIG. 11 and radii of eyeglass lens 5 ra, rb, ro%
The intersection points Qa%Qb, Qc, and Qd with rd are the positions on the circumference of the spectacle lens 5 where the bevel curve is actually formed. Here, the width ΔQ is the maximum deviation width of the bevel curve, and in the case of the spectacle lens 5, the bevel curve is formed within this width ΔQ. Next, the control unit 53 finds the center of the minimum value in the edge thickness (step 12 in FIG. 6). In this case, a point Qa is determined as the center of one point as shown in FIG. In this way, if the intersection points Qb and QaSQd in FIG. 11 are written in FIG. 10 based on the constant f next points Qa t -, the polygonal curve 100 shown in FIG. 10 is obtained (step 74 in FIG. ). This polygonal line car 1100 corresponds to a bevel curve. As shown in Figure 10, points Qa and Qb
, Qc, and Qd are within the shaded area, the bevel car 110 can be attached without coming off on the HX lens edge thickness. When the curve is large, the bevel curve 100 may deviate from the lens edge thickness at a value other than the minimum value among the edge thicknesses.In that case, the control unit 53 sets the lens edge thickness to the minimum value among the edge thicknesses, that is, in this example. moves the point Qa in the direction of one of the end faces (step 76 in Figure 6) and finds the remaining three points Qb, Q from the approximate tracing curve.
a, Qdt is calculated, and it is checked whether all the points fall within the middle white of the edge thickness of the eyeglass lens 5 (step 77 in Fig. 6). If it is confirmed that they fall within the white range, the finishing step begins (step in Fig. 6). 79), otherwise the specified curve is inappropriate, so a display etc. is performed and the specified curve value is changed (step 78 in FIG. 6).

After confirming that the bevel curve is on the lens edge thickness in this way, the control section 53 first controls the pulse motor 2.
4), raise the pressure mold receiver 22 so that it comes off the contactor 250, and then input a pulse to the pulse motor 14 so that the position where the bevel curve of the eyeglass lens 5 is attached is exactly above the ■-shaped grindstone 21. .

In the case as explained in FIG. 10, the control section 53 applies pulse gold to the pulse motor 14 so that the point Qa at the point a of the spectacle lens 5 is exactly on the V-shaped grindstone 21.

The control unit 53 rotates the rotary motor 56 of the V-shaped grindstone 21, sends pulses to the pulse motor 24 again, and
In order to form a bevel on the eyeglass lens 5 and to form a complete bevel curve, the pulse motor is applied while applying pulses to the pulse motor 10 and in synchronization with the encoder 32. -14, the pulse f is inputted and the previously determined bevel curve (see FIG. 10) is formed on the outer peripheral surface of the spectacle lens 5. As a result, a bevel curve is formed on the eyeglass lens 5 that matches the rim curve specified by & machining designation 1 (.

Note that in order to obtain the edge thickness of the eyeglass lens 5 (23), in the above explanation, a concave contact 2 as shown in FIG. 3 is used.
50, the edge thickness of the eyeglass lens 5 can also be determined by using a convex contact 250' as shown in FIG. In this case, in order to bring the spectacle lens 5 into contact with both sides of the convex part of the contactor 250', the width of the convex part is required as data, and the movement of carrying the spectacle lens 5 over the convex part to the opposite side is necessary. It becomes necessary.

Further, the nose frame 4 is located close to the eyeglass lens 5.
The glasses lens 5, which has finished hulling and obtained the extreme value, is detected by the front sound microphone generated by grinding minute portions of both end faces with the hulling grindstone 20, and the photo of the detection unit 25 is detected. A signal similar to the signal from the ink club 252 can be obtained, and the position of the edge of the eyeglass lens 5 can be measured.

Similarly, it is also possible to use a vibration sensor or the like instead of a microphone.

As described above, according to the present invention, an optimal generation curve can be automatically determined by measuring the entire edge thickness of any 24) lens.
Even people with little experience can easily process eyeglass lenses in a short time and without mistakes, and there is no need to be attached to a processing machine.Not only does it have the 10 points, but it can also be expected to save labor in the entire processing process. .

Furthermore, the device of the present invention is combined with a device that automatically measures the rim shape of the eyeglass frame and converts the relationship between the radius of the mold and the angle into an electrical signal, and the pulse motor 24 uses the signal to move the mold receiver 22 up and down. This movement is effective because it allows spectacle lenses to be manufactured without the need for stamping, and allows the spectacle lens to be accurately matched to the spectacle frame.

[Brief explanation of drawings]

FIG. 1 is a perspective view of an embodiment of the device according to the present invention, FIG. 2 is a view of the device in FIG. 1 seen from the rear, FIG. 3 is a configuration diagram of the detection section, and FIG. A cross-sectional view of the ground lens, Figure 5 & A diagram of the eyeglass lens and grindstone when the eyeglass lens is considered as a circle, Figure 8 is a graph visually showing the data from Figure 7, Figure 9 is a diagram of the relationship between the eyeglass lens and the contact, and Figure 10 The figure is a graph visually explaining the data obtained from Figure 9, Figure 11 is a tangent on the radius R and the intersection point Q with the average value rmean of the radius r, and Figure 12 is another example of the contactor. This is an example. [Explanation of symbols of main parts] 3...Support shaft, 4...Head frame, 5
... Glasses lens, 9 ... Pressure type, 14 ... Pulse motor for moving head frame 20 ... Hulling grindstone, 21 ... ■-shaped grindstone for bevel processing, 24 ... Pulse for upper and lower lens shape Motor, 25...detection section.

Claims (1)

[Claims] It is provided with a chucking mechanism capable of holding and rotating the eyeglass lens, and is configured to be movable both horizontally and in the radial direction of the eyeglass lens, and is continuously connected to the head frame and allows the head frame to move horizontally. a drive device, a drive device installed on the head frame to rotate a lens rotation shaft equipped with a chucking mechanism, a grindstone installed on the main body frame, and an IC installed on the main body frame and attached to an end of the lens rotation shaft. A lens periphery processing machine characterized by having a drive device for moving a pressing mold up and down, and a lens position detection device provided close to the grindstone.