JP2771547B2 - Eyeglass lens peripheral edge chamfering device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a spectacle lens peripheral edge chamfering apparatus used for chamfering both side corners of an eyeglass lens.

(Prior Art) In general, in order to mount a spectacle lens on a lens frame of a spectacle frame, it is necessary to bevel or groove a peripheral portion of the spectacle lens. FIG. 9 and FIG. 10 schematically show the principle of beveling a cloth lens. The Fig. 9, first in FIG. 10, now, when processing bevel portion D of the acute radius of curvature Re in the periphery of the fabric lens L, the lens rotation axis O _L and the grindstone on the meridian having a radial gamma _A The center distance of E is l _A , and the lateral movement position of the lens L is Y _A.

In this fabric lens L, the bevel portion D having a radius of curvature Re
When the position corresponding to the diameter wire is also provided, in the conventional ball mill, the center distance l _B is changed only by l _B = l _A -x = l _A- (γ _A -γ _B ) and the lens L Move the horizontal movement position by y
It was configured to Y _B.

As an apparatus for chamfering the corners on both sides of the beveled portion D of the lens L to be processed, for example, there is a lens outer peripheral processing machine as shown in FIGS. -15964).

In this lens peripheral processing machine, a lens 4 to be processed is held between lens axes 2 and 3 of a main body 1 to rotate the lens axes 2 and 3 at low speed, while a cutting blade 6 driven by a motor 5 By moving the cutting blade 6 to the peripheral surface of the lens 4 to be processed by moving the cutting blade 6 to the side 4, the shape of the lens 4 to be processed is roughly cut into the lens frame shape of the eyeglass frame to be mounted. .

In addition, the beveling grindstone 7 is moved onto the lens 4 to be roughly cut in this manner, and the beveling grindstone 7 is driven to rotate by the motor 8 so that the beveled grindstone 7 is placed on the periphery of the lens 4 to be machined by its own weight. As shown in FIG. 9, a beveled portion D is formed on the peripheral edge of the lens 4 to be processed. In this processing, since the lens 4 to be processed is rotated by the lens axes 2 and 3, the length of the lens 4 to be contacted with the beveled grindstone 7, that is, the moving radius changes with the rotation. However, the beveling grindstone 7 is vertically swung by the swingable arm 9 in accordance with the change in the moving radius.

The lens to be processed 4 which is beveled by this machine has corner portions a and b on both sides of the bevel portion 4a.

In order to chamfer the corners a and b, in the above-described lens outer peripheral processing machine, the angle θ of the V-groove A is larger than the angle θ of the beveling grindstone 7.
Is used.

The chamfering grindstone G is mounted on an output shaft of a motor M, and a support plate SP holding the motor M is mounted on a support shaft SA so as to be rotatable and movable in the axial direction.

(Problems to be Solved by the Invention) In such a lens peripheral processing machine, an operator presses the support plate SP by hand and presses the chamfering grindstone G against the beveled portion D of the lens 4 to be processed. By doing so, the corners a, b
Chamfering. However, there is a problem that skill is required because the amount of chamfering is manually performed while visually checking by an operator.

In addition, since the chamfering of the corners a and b is performed separately, there is a problem that the chamfering operation takes time.

Therefore, the present invention does not require skill in chamfering the corner of the beveled portion of the lens to be processed which is beveled,
Moreover, it is an object of the present invention to provide a spectacle lens peripheral edge chamfering apparatus capable of shortening a chamfering operation time.

(Means for Solving the Problems) In order to achieve this object, the present invention provides a carriage mounted on a main body so as to be vertically movable and movably laterally, and a pair of lenses mounted on the carriage in a lateral direction. Shaft, edge thickness measuring means for measuring the edge thickness of the peripheral edge of the lens to be processed held between the pair of lens axes, corresponding to each radius, and rotatable about an axis parallel to the lens axis. A chamfering grindstone disposed above the lens axis and mounted on the main body so as to advance and retreat with respect to the lens to be processed; A moving arm member, an elastic member for suppressing the rocking of the rocking arm member, and a lifting / lowering drive control of the carriage based on information from the edge thickness measuring means, and the rocking arm member by the elastic member. Control the swing of And a control circuit for controlling the chamfering depth of the corners on both sides of the eyeglass lens.

(Example) Hereinafter, an example of the present invention will be described with reference to the drawings.

Device Configuration FIGS. 1 to 6 show a first embodiment of the present invention. FIG. 1 is an external perspective view showing a part of the configuration of a lens processing apparatus, ie, a ball mill, and a configuration of a chamfering apparatus according to the present invention, together with an electric circuit block diagram of a beveling control system and a chamfering control system. FIG.

The casing 10 is provided with a grindstone chamber 11, in which a grindstone rotated at high speed by a motor (not shown) is stored. This whetstone is composed of a rough whetstone 12 and a bevel whetstone 13. A bearing 14 is provided behind the housing 10, and a carriage turning shaft 21 is fitted into the bearing 14 so as to be rotatable and movable in the axial direction. The rear end of the carriage 20 is fixed to the carriage pivot 21. Thus, the carriage 20 can turn around the carriage turning shaft 21 and can slide in the axial direction. Protrusions 20a and 20b are provided on both sides of the free end of the carriage 20, and the protrusions 20a and 20b hold coaxially disposed lens shafts 22a and 22b, which are mounted on the lens shafts 22a and 22b. The lens L to be processed is clamped and held. Further, the lens shafts 22a and 22b
It is rotated via a known rotation transmission mechanism Q by a lens axis motor 25 disposed therein. A template T is attached to the other end of the lens shaft 22b by well-known template holding means 24.

On the side of the housing 10, there is an L-shaped arm member 30 which is a carriage lateral moving means. The arm member 30 is slidably supported by an axial rail member 15 protruding from the side wall of the housing 10. Further, a pivot shaft 21 of the carriage is attached to one end 34 of the arm member 30 so as to be rotatable but not to move laterally. The arm member 30 is further screwed with a feed screw 33 attached to a motor 32 for lateral movement (Y-axis) on the fixed frame side (not shown). The rotation of the motor 32 moves the arm member 30 along the Y axis, and the movement of the arm member causes the carriage 20 to move in the same direction by the same amount. At the other end of the arm member 30, a pulse motor 200 as an X-axis motor is held, and a mold receiving stand 38 having a structure described later is attached. The mold receiving table 38 has a mold receiving body 38b and a contact piece 38c for contacting the template.
38c is supported at one end of the mold receiving body 38b via a shaft 207. Moreover, the template T is located on the upper surface of the mold receiving table 38, that is, the mold receiving surface 38.
It is configured to abut a. Here, the mold receiving surface 38a has the same radius of curvature as the grinding line of the beveling grindstone 13.

Further, a spring 206 is interposed between the abutment piece 38c of the mold receiving body 38, and the abutment piece 38c is lifted up by the spring 206 when the template T does not abut on the mold receiving surface 38a. Have been. Further, a light-shielding bar 205 is passed to the contact piece 38c. Mold support 38
A detector 204 is provided on the upper surface of the light emitting element 204. The detector 204 includes a pair of a light emitting element 204a and a light receiving element 204b that can block an optical path with the light-shielding rod.

The female screw 203 fixed to the lower surface of the mold receiving base 38 is the arm member 3
0 is slidably inserted into the hole, and the pulse motor 200
Is screwed with the feed screw 201 attached to the. A guide rail 202 is attached to the lower surface of the mold receiving body 38b, and is inserted into a guide hole 208 of the arm member.

FIGS. 8C and 8D show the main body 10 of the ball mill shown in FIG.
As shown in the figure, the chamfering device main body 40 of the eyeglass lens both-side corner chamfering device is mounted.

The chamfering device main body 40 includes an arm support member 41 having a lower portion bifurcated from the branch portions 41a, 41a, rubbers 42, 42 mounted on opposing surfaces of the branch portions 41a, 41a, and an arm support member 41.
A support shaft 43 attached to the upper end of the lens in parallel with the lens shafts 22a and 22b, and a swing arm rotatably held by the support shaft 43
Has 44.

The swing arm 44 includes a pair of side plates 45, 45, and the side plates 45, 45.
And the frame support shafts 47, 47 bridged close to each other between the intermediate portions between the side plates 45, 45 in parallel with the lens shafts 22a, 22b. . An arm-side stopper 45a is provided at one end of the side plate 45.

Further, the chamfering device main body 40 includes slide support members 48, 48 attached to the frame support shafts 47, 47 slidably in the axial direction by bearings 48a, 48a, and a slide fixed to the slide support members 48, 48. Frame 49 and slide frame 49
A chamfering motor 51 fixed with screws 50, a chamfering grindstone 52 detachably fitted to an output shaft 51a of the motor 51, and a nut 53 fixing the chamfering grindstone 52 to the output shaft 51a. Have.
The output shaft 51a is provided in parallel with the lens shafts 22a and 22b, and the chamfering grindstone 52 includes a pair of chamfering grindstone members 52a and 52b. As shown in FIG. 8 (G), the inclination angle δ of the chamfered slope 52a ′ of the chamfering grindstone member 52a is equal to the chamfered slope of the chamfered grindstone member 52b.
It is set smaller than the inclination angle γ of 52b ′. The chamfering grindstone 52 is used by being arranged on the lens shafts 22a and 22b. In this arrangement, the branch portions 41a, 41a are fitted to the front wall 10a of the main body 10 of the rasing machine as shown in FIGS. 8C and 8D, and the swing arm 44 is mounted on the lens shafts 22a, 22b. This is done by arranging.
Note that the chamfering device main body 40 is detached from the main body 10 at the time of the copying process and the beveling process using the template of the lens to be processed.

On the other hand, a stopper column (not shown) of the chamfering device is provided on the main body 10 so as to be able to move up and down from the upper surface toward the space between the protrusions 20a and 20b of the carriage 20, and a fixed stopper is attached to the upper end of the stopper column. Mounting portion 54 is provided. As shown in FIG. 8 (E), the mounting portion 54 is formed with a mounting hole 55 penetrating vertically, and a shaft portion 56a of an arm stopper receiver 56 is fitted into the mounting hole 55 so as to be vertically movable. Stopper screw as a fixed stopper at the lower end of the mounting hole 55
57 is screwed. The stopper screw 57 is fixed by a lock nut 58. A cushioning elastic member 59 made of rubber, synthetic resin, or the like is mounted between the arm stopper receiver 56 and the mounting portion 54. This elastic member 59
Is compressed when the own weight of the swing arm 44 acts on the arm stopper receiver 56 via the stopper 45a, so that the shaft portion 56a of the arm stopper receiver 56 can abut against a stopper screw 57 as a fixed stopper. ing.

In FIG. 1, reference numeral 100 denotes a beveling control device which is also used for driving control of such a chamfering device.

The beveling control device 100 includes a counter 301 that is controlled by a signal from the detector 204 and counts pulses from the pulse generator 103, an arithmetic circuit 106 including a microprocessor that receives count data from the counter 301, and an arithmetic circuit. Circuit 1
A control circuit 108 for controlling the motors 25, 32, etc. during beveling,
Calculation program memory 107 for storing calculation programs
And a sequence program memory 120 for storing a machining control sequence, a curve input device 121 for inputting a bevel curve value to the arithmetic circuit 106, a determination circuit 302 for determining a descending amount of the mold receiving table 38, and driving of the motor 32. Driver 1 used for
04 and a driver 102 used to drive the lens axis motor 25
And a driver 300 used to drive the pulse motor 200
And so on. The memory 110 includes first to fourth memories used for beveling and a fifth memory used for chamfering.
To a seventh memory.

Detailed configurations and operations of the beveling control device 100 and the chamfering device will be described in the following operation description.

(1) Grinding of lens shape and storage of chamfering information Step 1 In FIG. 1, the template T is mounted on the lens shaft 22b of the carriage 20 shown in FIG.
Are held at an initial home position as shown in FIG. 1 by known holding means (not shown). In this state, when the switch LS for starting the lens shape grinding is turned on, the control circuit
108 controls the driver circuit 300 to control the pulse generator 103
Is supplied to the pulse motor 200, the pulse motor 200 is rotated forward, and the mold receiving table 38 is raised. At this time, the number of pulses supplied to the pulse motor 200 is
Counted at 01.

When the contact piece 38c of the mold receiving table 38 contacts the template T, the detector 204 outputs the detection signal to the counter 301 as the stop signal S, and stops the pulse coefficient of the counter 301. The counter 301 inputs the count value at that time to the arithmetic circuit 106.

Here, as shown in FIG. 3, the mold receiving surface 38a of the mold receiving table 38 is provided.
Is the bevel groove bottom 13 of the bevel grindstone 13 as shown by the two-dot chain line.
It has a radius of curvature that matches the radius of curvature R of a. When the rotation center or the lens axis 22a of the lens L, and a predetermined distance between the rotation center O _L and the grindstone groove bottom 13a and 22b is M, the mold cradle 38 is raised, the type receiving surface 38a is the template T Assuming that the amount of movement of the mold receiving table 38 when contacted with e is e _i , the distance L ₀ ≒ L between the lens 23 and the rotation axis Oe of the beveling grindstone 13 is the distance L L between the lens and the lens shaft-grinding wheel The distance M and the grinding wheel radius R are given as L = M + R.

The increase amount e _i from l _i = (M-e _i) of the center distance l _i the type cradle in the radial [rho _i of the template T + R ......... (7) (where, i = 0, 1, 2, 3,... J... N) in the first memory of the memory 110.
The template radius vector [rho _i corresponding to 111 are stored in the [rho _i address.

When this is completed, the control circuit 108 then proceeds to the driver 300
Is controlled to reverse the motor 200 and lower the mold receiving table 38 by a predetermined Δd. Then, the motor 25 is rotated via the driver 102, and the template T is moved by the unit angle Δθ as shown in FIG. By rotating, the template moving radius ρ _{i + 1} is positioned on the straight line X. Then, when the template T is rotated by the unit angle, the control circuit 108 outputs a reset signal to the counter 301 to reset the counter 301. If there is a detection output from the detector 204 during this unit angle rotation, the determination circuit 302 receives the command and
Is determined not to have dropped below the length of the next radius ρ _{i + 1} ,
This is output to the control circuit 108. The control circuit 108 receives the command from the determination circuit 302, and further lowers the mold receiving table 38. When the lens axes 22a and 22b are rotated by a unit angle,
Again rotate the motor 200 forward via the driver 300, and
38 was elevated to measure the center distance l _{i + 1} of the radius vector ρ _{i + 1.}
Hereinafter, this is repeated, and the whole template radial radius ρ _i (i = 0,1,2,3,
... N) between the axes l _i (where i = 0,1,2,3,
... N).

Then, Zendo径[rho each axial distance over _i (l _i) means the template radius vector [rho _i in the first memory 111 [rho _i address (i
= 0, 1, 2, 3,... N).

Step 2 Next, the arithmetic circuit 106 reads the axial distance data (l ₀ ) of the address ρ ₀ stored in the first memory 111 in accordance with the arithmetic program memory 107, and as shown in FIG. determination of the distance from the radius R and the center distance l ₀ of the grinding line 13a to the virtual working point P ₀ of the same type [rho _0. That is, the rotational axis center Oe and lens axis 22a of the grindstone 13, a straight line connecting the rotation center O _L of 22b as a reference line X, the virtual machining point the intersection of the grinding line 13a of the reference line X and the grindstone 13 Assuming that P ₀ , the arithmetic circuit 106 calculates the distance from the lens rotation axis center _OL to the virtual processing point P ₀ [hereinafter referred to as the virtual processing radial length ρ
_i (l _j )] is determined by using ρ _i (l _j ) = l _i −R (3) (where i, j = 0, 1, 2, 3,..., n). In this step, the virtual machining radius length ρ ₀ (l ₀ ) of the radius radius ρ ₀ specified as i = 0, j = 0 is obtained as ρ ₀ (l ₀ ) = l ₀ −R from the equation (3). .

Step 3 Next, the arithmetic circuit 106 sets the lens axes 22a and 22b to the unit rotation angle Δ
θ rotation, that is, l _{j + 1} (in this step, l
_{0 + 1} = l ₁ the axial distance l ₁ of [rho ₁ at address) read from the first memory 111, a virtual processing radius vector length [rho ₀ virtual working point P ₁ of the radius vector [rho ₀ in the inter-axis distance l ₁ (L _o ) Using Asking.

FIG. 4 shows a template T to facilitate understanding of this relationship.
The instead to the unit angle Δθ rotation, by Δθ rotation of the grindstone 13 to the lens axis O _L times despite grinding wheel grinding line when the
13a is shown as being in contact with the template T. Both of these notations indicate the same phenomenon.

Step 4 Next, the virtual machining radial length ρ _i (l _j ) obtained in Step 2
And the virtual machining radial length ρ _i (l _{j + 1} ) obtained in step 3 are compared. At this stage, ι = 0 and j = 0, so ρ
₀ (l ₀ ) and ρ ₀ (l ₁ ) are compared. The symbol “/” in the flowchart of FIG. 2 means that the values before and after that are compared (the same applies hereinafter). Then, ρ _i (l _j ) ≦ ρ _i (l
_{j + 1} ), that is, in the case of ρ ₀ (l ₀ ) ≦ ρ ₀ (l ₁ ), the process proceeds to step 10 described later. Also, ρ _i (l _j )> ρ _i
If (l _{j + 1} ), that is, ρ ₀ (l ₀ )> ρ ₀ (l ₁ ), the process proceeds to the next step 5.

In the example of FIG. 4, since ρ ₀ (l ₀ )> ρ ₀ (l ₁ ), the process proceeds to the next step 5.

Step when the type 5 plates were further unit angle Δθ rotation l _{j + 2} axis distance data of [rho ₂ address (l _{0 + 2} ≡l ₂ in this step) (l ₂₎
Is read from the memory 111 and the virtual machining radius length ρ ₀ (l ₂ ) is obtained by using the above equation (4).

Step 6 The virtual machining radius length ρ _i (l _{j + 1} ) of Step 4 is compared with the virtual machining radius length ρ _i (l _{j + 2} ) of Step 5. At this stage, since i = 0 and j = 0, ρ ₀ (l ₁ ) and ρ ₀ (l ₂ )
Compare with When ρ _i (l _{j + 1} ) ≦ ρ _i (l _{j + 2} ), the process moves to the next step 7, where ρ _i (l _{j + 1} )> ρ _i (l
_{In the case of j + 2} ), the process proceeds to step 6 '. In the example of FIG. 4, since ρ ₀ (l ₁ ) <ρ ₀ (l ₂ ), the process proceeds to the next step 7.

Step 6 'If ρ _i (l _{j + 1} )> ρ _i (l _{j + 2} ), that is, ρ ₀ (l ₁ )> ρ _o (l ₂ ) in the previous step 6, if this step is performed, center distance data corresponding to the template T was the unit angle Δθ rotation _{{l (j + 1) +2} , θ (j + 1) +2} from between the axes of the distance l _{(j + 1) +2} The virtual machining radius length ρ _i (l _{(j + 1) +2} ) is obtained. Then, it is compared with the previous data ρ _i (l _{j + 2} ). Until the virtual machining radial length based on the updated inter-axis distance becomes larger than the virtual machining radius length of the immediately preceding inter-axis distance, the virtual machining radial length is sequentially determined based on the successive inter-axis distance data. Seeking and comparing.

Step 7 If it is determined in the previous step 6 that ρ _i (l _{j + 1} ) ≦ ρ _i (l _{j + 2} ), ρ _i (l _{j + 1} ) is actually machined by the grindstone 13 at the radius ρ _i . Is determined to be the working radius. At this stage, that is, in the example of FIG. 4, i = 0 and j = 0, so that the moving radius ρ ₀
Is determined as the working radial length ρ ₀ (l ₁ ) at.

Step 8 The arithmetic circuit 10 determines the machining radius length ρ determined in the previous step 7.
Working radial length data (▲, ▼), as a set of the lens axis rotation angle θ _{j + 1} corresponding to this inter-axis distance l _{j + 1} of _i (l _{j + 1} ).
▼) is stored in the second memory 112 of the memory circuit 110. In the example of FIG. The machining radius (▲ ▼, ▲ ▼) is the template radius ρ
₀ corresponds to the memory [rho ₀ address of the second memory 112.

Step 9 Steps 3 to 8 are sequentially executed for each moving radius ρ _i until a working radius length is obtained for the entire moving radius ρ _i (i = 0, 1, 2, 3,..., N) of the template T. . For example, the radius vector [rho ₀ processing radius vector data in the example of FIG. 4 (▲ ▼, ▲
▼) Since the obtained transfer from the radius vector [rho ₀ Step 7 'in the radial [rho _1, perform the steps 3-8 for new rata of radius vector [rho _1, the processing radius vector relates radius vector [rho ₁ The length is obtained, and the result is stored in the second memory 112 as the template radius ρ ₁
It is stored in the [rho ₁ address to correspond to. Processing radius vector length for the final radius vector [rho _n the following the same procedure (▲ ▼, ▲
▼) are calculated and calculated, and these are calculated as ρ _{N in} the second memory unit 112.
Store the address.

FIG. 6 shows the relationship between the working radius data (（, ，) and the template radius ρ _i . The template T is the lens axis 22a,
22b is rotated about the axis Oe, and the rotation amount _i from the reference line H of the template
When the template moving radius ρ _{i in} the direction of XΔθ is positioned so as to be located on the reference line X, the lens L is lowered at the grinding line 13a of the grinding wheel 13 and the descending point P _i , and the processing movement of the processing line is performed. The diameter is ▲ ▼ and the processing angle is ▲ ▼.

Step 10 When ρ _i (l _j ) ≦ ρ _i (l _{j + 1} ) is satisfied in step 4, the process proceeds to this step, and as shown in FIG. 5, the template T is moved toward the lens axes 22a and 22b. The inter-axis distance ln of the address ρ _n of the first memory 111 of the rotation angle θn inverted by the unit angle Δθ.
The virtual machining radius length ρ _i (l _j-1 ) is obtained from equation (4) based on Center distance [rho for moving radius [rho ₀ in the example of FIG. 5
_{Use 0-1} ≡ln to calculate the virtual machining radius length ρ ₀ (ln) Asking.

Step 11 The virtual machining radius length ρ _i (l _j ) obtained in step 2 is compared with the virtual machining radius length ρ _i (l _j-1 ) obtained in the previous step 10. Then, when ρ _i (l _j ) ≦ ρ _i (l _j-1 ), the flow proceeds to the next step 12, and when ρ _i (l _j )> ρ _i (l _j-1 ), the flow proceeds to step 11 ′. Transition. In the example of FIG. 5, i = 0,
ρ ₀ (l ₀ ) and ρ ₀ (l _0-1 ) where j = 0, that is, ρ ₀ (l
n) are compared with each other. If ρ ₀ (l ₀ ) <ρ ₀ (ln), the process proceeds to the next step 12.

In the counting step 11 'Before step _{11 ρ i (l j)>} ρ i is migrated to the present step is determined _{(l j-1)} and the arithmetic circuit 106 further units template T to the lens axis O _L times fairly The inter-axis distance data when the angle Δθ is reversed, that is, as the new inter-axis distance l _j−1 , the inter-axis distance data (l _{(j−1) −1} , θ _{(j−1) −1} ) Distance l
_{Using (j-1) -1} (not shown), the virtual machining radius length ρ _j (l _{(j-1) -1} ) is calculated by Expression (4), and the previous virtual machining radius length ρ is calculated. _i (l _j-1 ). This operation is repeated until the sequentially updated virtual machining radius becomes smaller than the immediately preceding virtual machining radius.

Step 12 When ρ _j (l _i ) ≦ ρ _i (l _j-1 ) in the previous step 11, the process proceeds to this step. Then, the arithmetic circuit 106 calculates ρ
_i (l _j ) is the moving radius length actually processed by the grindstone 13 on the moving radius ρ _i Is determined, and the rotation angle θ of the template T corresponding to the axis distance l _j is determined.
Combined with _j , machining radial length data (▲ ▼, ▲
▼).

In the example of FIG. 5, i = 0 and j = 0, and these are determined as the machining radial lengths. Data (▲ ▼, ▲ ▼) becomes is obtained and stored in the [rho ₀ address of the second memory 112 in step 8.

When executed up to step 9, each radial radius ρ _i (i
= 0,1,2,3, ... n), the machining radial length data Is obtained, the corresponding [rho _i address indicating each template radius vector [rho _i of此these second memory 112 (i = 1,2,3, ...... n ) it is stored in.

Step 13 A known rough grinding process is executed by the rough grinding stone 12 following the template T.

Step 14 The control circuit 108 selects any four template radials ρ _a , ρ _b , ρ _c , and ρ _d from the second memory 112. The motor 25 is driven via the driver 102 on the basis of the first template radial radius ρa to rotate the lens shafts 22a and 22b by ( _a XΔθ), and the template T is positioned on the reference line X (X axis). The radius is set so that ρ _a is located.

Next, the control circuit 108 drives the motor 200 to
It is detected whether or not the coarsely ground lens L, which has been coarsely ground in the previous step 12, comes into contact with the beveling grindstone 13 as shown in FIG. 7A.

At this time, the contact point S of the lens L to the beveled grindstone 13 is stored at the address ρa of the second memory 112 corresponding to the template radius ρ _a as schematically shown in FIG. 7B. Machining angle of machining radius length data (▲ ▼, ▲ ▼) ▲ ▼ minute direction of plate radius ▲ ▼ (since this radius ρa is on the X axis), that is, it is rotated ▲ ▼ from the X axis. Processing line K
It is in.

A predetermined number of pulses corresponding to a predetermined reference height χD is supplied from the pulse generator 103 to the motor 200 via the driver circuit 300 under the control of the control circuit 108, and the number of pulses is reduced to the reference height χD. The cradle 38 is lowered. At this time, the motor 20
The number of pulses supplied to 0 is counted by the counter 301. Whetstone 13
Is a two-stage V-shaped grindstone 13 'as shown in FIG. 7 (C), so-called "medium V grindstone", .DELTA.D is set to the gentle slopes 13b' and 13c '. If no contact is made at this time, the determination circuit 302 determines that the contact is non-contact because the detector 204 does not generate an ON signal even if the predetermined number of pulses are supplied from the pulse generator 103, and the control circuit 108 Output to The control circuit 108 includes a motor
200 is inverted to return the lens axes 22a and 22b to the initial height. Then, the control circuit 108 operates the motor 32 to move the seventh minute distance in the unit minute distance Y-axis direction (axial direction of the lens axis).
After leftward on the figure to move the carriage 20, and re-execute the above operation, the lens front edge end L _f are repeated until contact at the reference height χD the front grinding surface 13b of the grindstone 13. When the reference height χD is reached, the detector 204
It outputs an ON signal and a stop signal S to the counter 301. The number of pulses supplied from the pulse generator 103 to the motor 32 is counted by the counter 301, and the counter 301 has a double structure that can independently count the number of pulses supplied to the motor 200 and the motor 32. . Judgment circuit
The control circuit 108 that has received the signal from 302 sends the count value of the counter 301 to the arithmetic circuit 106, and temporarily stores it in an internal memory (not shown) in the arithmetic circuit 106. At the time of contact at the reference height χD, this is stored as the lens movement amount Y _fi in the third memory 113 in association with the template plate radius ρ _i (in the case of the present embodiment, this corresponds to the radius ρ a). _Is stored as Y _fa .) The counter 301 has been reset at that time. While lowering the mold receiving table 38 for the first time, the reference height χD
In the course of descent until, when the front edge end L _f of rough grinding already lens L abuts the mold pedestal 38 the number of pulses has been supplied from the pulse generator 103 to the motor 200 in order to lower the counter The counting is performed at 301, and the counting is stopped at the point of contact by the stop signal from the detector 204. Judgment circuit 30
Control circuit 108 receives a signal from the 2 sends the count value of the counter 301 at that time to the arithmetic circuit 106, as compared to the reference height KaiD, based on the inclination angle epsilon ₁ of V-shaped grinding wheel from the difference ΔχD The Y movement ΔY that stops is sent to the control circuit 108, and after the Y movement ΔY is moved to the right in the lens axis direction, the same operation is repeated again.

Then, until the side edge end L _b is the reference height χD of the lens L (the reference height χD is no problem different from the time of measurement of the front edge end L _f.), Edge end L _b The cradle 38 is lowered while detecting whether the abutment comes into contact with the front grindstone surface 13c of the grindstone 13. Here below in advance edge end L _f does not contact the front grinding surface 13b of the grinding wheel 13 positions, it goes without saying to keep moving the carriage to the right.

Operation of the latter is similar to the case of measuring the lens edge end L _f, only the movement in the Y direction is the opposite direction. Reference height χD
_Is stored as Y _bi in the third memory 113 in association with the template radius ρ _i (in the present embodiment, it is stored as Y _ba because it corresponds to the radius ρ _a). Is done).

In the same manner, the above-mentioned operation is executed for template radials ρ _b , ρ _c , ρ _d , and the corresponding Y movement amounts Y _fb , Y _fc , Y _fd and Y _bb , Y _bc , Y _bd
Is obtained and stored in the third memory 113.

The position of the contact point on the front side of the edge with respect to the Y-direction position of the grinding line 13a of the beveling wheel 13 at the reference height は D is χD / tanε ₁ ,
The position of the contact point on the rear side is ΔD / tanε ₂ .

The Y coordinate memory value Y _fi when the front contact is measured is calculated as χD / tan
Moving only epsilon _1, the front contact comes on grinding line 13a of the grindstone 13. The edge thickness W _{i at} this time is as follows: W _i = [(χD / tanε ₁ ) + (χD / tanε ₂ )] − | Y _fi −Y _bi |

The edge thickness W _i the lens axis 22a, is stored in the fifth memory in correspondence to the rotational angle theta _i and its radius vector [rho _i of 22b. At this time, the change rate ΔW _i of the edge thickness with respect to the change of the moving radius is stored in the fifth memory from each of the working radius ρ _i and the edge thickness W _i .

Then, the lens axes 22a and 22b and the lens L to be processed are
The lens L to be processed is lowered by xD in FIGS.
Radius ρ _i and edge thickness W _i when beveling is applied to the periphery of
The edge thickness W _i ′ between the corner portions a and b of the bevel portion at the time is the rate of change ΔV _i of the width of the V-groove between the grindstone surfaces 13 b and 13 c of the bevel grindstone 13.
And the rate of change ΔW _i . Then, the edge thickness W _i ′ is stored in the sixth memory together with the rotation angle θ _i and the moving radius ρ _i of the lens shafts 22a and 22b.

Here, the chamfering device main body 40 is connected to the main body 10 as shown in FIG.
And the stopper 45a of the swing arm 44 abuts against the arm stopper receiver 56, and the horizontal axis including the output shaft 51a of the motor 51 when the shaft portion 56a of the arm stopper receiver 56 abuts against the stopper screw 57. Is a virtual line, and this virtual line K
And the distance between the bevel grinding wheel 13 and the rotation center θe is LX.
Also, the mold receiving base 38 is raised by eH _i , and the lens L to be processed is
The distance between the lens axis 22a, 22b and the imaginary line K when the upper part of the lens is brought into contact with the chamfered slopes 52a ', 52b' of the V groove of the chamfering grindstone 52 is And Further, the radius of the chamfering grindstone 52 is r ₀ , the radius of the chamfering grindstone 52 to the bottom of the V-groove is r ₁ , and the rotation angle of the lens shafts 22a and 22b is θ.
The moving radius of the lens L to be processed to the contact portion of the lens L on the mold receiving table 38 at _i The height of the upper bevel portion D is Δh _i , and the edge thickness of both side corners a and b of the bevel portion D is The moving radius including the contact portion of the lens L to be chamfered to the chamfering grindstone 52 with the moving radius advanced by π from The radius up to this abutment is The height of the beveled part D ' The edge thickness between a 'and b' between both corners of the beveled part D 'is And the distance from the imaginary line K at this position to the contact portion of the lens L to be processed to the V groove is The depth of the V groove of the chamfering grindstone 52 is h ₀ , and the maximum width of the V groove is Wx.

Using the codes of such conditions, the edge thickness W _i ′, the rotation angle θ _i , the radius ρ _{i, and the} like stored in the sixth memory are used. Also, in equation (a) Is Becomes

From these equations (a) and (b) Is Becomes

Lx is Therefore, the vertical movement control amount of the mold stand at this position Is calculated by the arithmetic circuit 106 from (A) to (D). Can be obtained as

Therefore, the control information necessary for chamfering obtained in this way, ie, Is the radial radius corresponding to each rotation angle θ _i of the lens axis. Is stored in the seventh memory in correspondence with the above, and is used at the time of chamfering processing to be described later. And in this beveling, Amount plus chamfered height h _w becomes possible to perform a control for increasing the.

On the other hand, if the bevel position of the solid line is attached to the position of the edge q: S based on the edge thickness W _i described above, the movement amount in the Y direction at that time is: Is required.

Center of the bevel spherical surface including the machining point P _i is the optical axis of the lens to be processed is attached eccentrically to the lens axis of the carriage, not located on the rotation axis of the lens axis. Therefore, the amount of deviation of the center of curvature of the beveled sphere in the three-dimensional coordinate axis (X, Y, Z) direction corresponding to the lens axes 22a and 22b of the lens L to be processed is
Let A, B, and C be the radius of curvature Re of the bevel sphere. Becomes

Therefore, the deviation amounts A, B, C and the curvature radius Re are determined by the machining angle ▲
Using ▼ and machining radius length ▲ ▼, the Y direction movement amount of machining points P _a , P _b , P _c , P _d corresponding to at least four template plate radiuses ρ _a , ρ _b , ρ _c , ρ _{d y a, y b, y c} , determined in a y _d (6) wherein the the obtained _{y a, y b, y c} , by substituting y _d is determined by solving the above equation (7). For a machining point P _i corresponding to an arbitrary template plate radius ρ _i , the movement amount yi is determined from the machining radius length data (▲, ▲ ▼) for the radius ρ _i stored in the second memory 112. A, B, C, Re can be obtained from the following equation (7). In the embodiment shown in FIG. 1, the curve input device 121 can be used to input the bevel position ratio q: S. In addition, when the user inputs the bevel curve value Ce using this input device 121, the arithmetic unit 106
Is (Where n is the refractive index of the lens, usually n = 1.525) is used to calculate Re, and the value of Re is substituted into the above equation (7), and the Y axis movement amount y _{i of the} lens based on an arbitrary bevel curve value Ce Can be requested.

The determined amount of movement y _{i in} the Y-axis during beveling of the lens
Is stored in the address ρ _{i of} the fourth memory 114 in correspondence with the template radius ρ _i , and the Y-axis direction movement amount data (ρ _i , y _i ) (i = 0,
1,2,3 ... N).

Step 15 At the time of beveling grindstone processing, the control circuit 108 controls the motor 21 and the motor 32 using the Y-axis direction movement amount data (ρ _i , y _i ) from the fourth memory 114 so that the template plate radius ρ _i becomes X When located on the axis,
Control is performed so that the carriage 20 comes to the position of y _i . Thereby, a bevel vertex can be formed at the position of the specified ratio q: S over the entire edge of the lens. Also, bevel curve value
When Ce is given, processing is performed so that the bevel apex of the whole circumference is located on the bevel surface having the curve.

Incidentally, in step 14, assuming that the lens L is eccentrically attached to the lens axis of the carriage, the lens drop amounts χD _a , χD _b , based on the four template radials ρ _a , ρ _b , ρ _c , ρ _d are assumed. χ
D _c and χD _d are obtained, and the movement amount yi in the Y-axis direction is obtained using the expressions (6) and (7). If the lens L is attached to the lens axis without any eccentricity. If it is guaranteed, the (7) of the shift amount a, B, since C are all zero, the movement amount y obtained from the lens drop KaiD _a based on a single template radius vector [rho _{a The} radius of curvature Re of the beveled spherical surface can be determined only by _a , the machining radius ▲ ▼, and the machining angle ▲ ▼. After the curvature radius Re is determined, the Y-axis based on an arbitrary template plate radius ρ _i using the equation (7). The direction movement amount y _i is the machining radius length data (▲ ▼, ▲) for the radius ρ _i of the second memory 112.
Can be obtained using ▼).

(2) Chamfering Operation When the above-mentioned lens shape grinding is completed, the operation of the ball mill, that is, the lens grinding device is stopped. In this state, when the chamfering apparatus main body 40 is mounted on the main body 10 as shown in FIGS. 8C and 8D and the chamfering switch MS is turned on, the control circuit 108 operates according to the sequence program in the sequence program memory 120. I do. Thereby, the control circuit 108
Is moved up to a predetermined height, that is, a position shown in FIG.
Of the seventh memory Is lifted and lowered in accordance with the formula (1), and chamfering is performed on both side corners of the beveled portion D of the lens L to be processed.

At the time of this chamfering, the mold receiving table 38 raises the chamfering grindstone 52 from the position of the height of Lx by hw through the lens L to be processed, slightly raises the swing arm 44 upward, and stops the stopper 45a.
From the arm stopper receiver 56 by HW. In this state, the chamfering grindstone 52 is pressed against the side corners a and b of the beveled portion D of the lens L to be processed by its own weight on the swing arm 44 side.
Before the lens L to be processed comes into contact with the chamfering grindstone 52, the chamfering grindstone 52 is driven to rotate by the motor 51.

When the corners a and b are chamfered by this rotation and pressure contact, the swing arm 44 is gradually displaced downward, and the stopper 45a comes into contact with the arm stopper receiver 56. After this contact, a part of the own weight on the swing arm 44 side is received by the elastic force of the elastic member 59, so that the pressing force by which the chamfering grindstone 52 is pressed against the lens L to be processed by the own weight on the swing arm 44 side. Is the swing arm
44 gradually decreases as it moves downward. The shaft portion 56a of the arm stopper receiver 56 is
When the abutment with the upper end of the oscillating arm 44 is stopped, the downward movement of the swing arm 44 is stopped, and the pressing force of the chamfering grindstone 52 against the lens L to be processed becomes zero, and the radial Will be completed. Therefore, by performing such a chamfering operation little by little corresponding to each moving radius, chamfering of a substantially uniform depth is performed on both side corners of the beveled portion of the lens L to be processed.

(Effects of the Invention) As described above, according to the present invention, a carriage mounted on a main body so as to be vertically movable and movably laterally, and a pair of lens shafts mounted on the carriage in a lateral direction, Edge thickness measuring means for measuring the edge thickness of the peripheral edge of the lens to be processed held between the pair of lens axes in accordance with each radial direction; and the lens being rotatable about an axis parallel to the lens axis. A chamfering grindstone disposed above the shaft and mounted on the main body so as to be able to advance and retreat with respect to the lens to be processed, and a swing arm member that rotatably supports and swings the chamfering grindstone An elastic member for suppressing the rocking of the rocking arm member; and a lifting / lowering drive control of the carriage based on information from the edge thickness measuring means, and a rocking motion of the rocking arm member by the elastic member. Control the surface of both sides of the lens to be processed Since a configuration having a control circuit for controlling the chamfering depth is employed, chamfering of both side corners of the lens to be processed can be automatically facilitated even by a non-expert, and the chamfering operation can be shortened. Further, the chamfering depth at both corners of the lens to be processed can be made substantially constant.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating an example in which a chamfering device according to the present invention is applied to a lens grinding device, FIG. 2 is a flowchart illustrating the operation thereof, FIG. 4 and 5 are schematic diagrams showing a method of obtaining machining radius data, FIG. 6 is a schematic diagram showing a relationship between a lens rotation angle, a machining radius length and a machining angle, and FIGS. 7 (A) and (A). FIGS. 8B and 8C are schematic diagrams showing a method for measuring the amount of lens descent, FIGS. 8A and 8B are schematic diagrams showing a method for obtaining the amount of movement in the Y-axis direction, and FIG. FIG. 8 (D) is a plan view of FIG. 8 (C), FIG. 8 (E) is a cross-sectional view taken along line EE of FIG. 8 (D), FIG. 8 (F) is an operation explanatory view of a section along line FF of FIG. 8 (C), FIG. 8 (G) is a partial explanatory view of FIG. 8 (F), FIG. 9 and FIG. Lens diameter and FIG. 11 is a schematic view showing the relationship of movement, FIG. 11 is a perspective view of a lens processing machine provided with a conventional chamfering device, and FIG. 12 is an explanatory diagram showing the relationship between the chamfering wheel and the lens to be processed in FIG. . 10 Main unit 12 Coarse whetstone 13 Beveled whetstone 22a, 22b Lens shaft 25, 32, 37 Motor 38 Die stand 40 Chamfering device main body 44 Swing arm 45a ... Stopper 51 ... Motor 52 ... Chamfering grindstone 56 ... Stopper receiver 56a ... Shaft 57 ... Stopper screw (fixed stopper) 301 ... Counter 302 ... Control circuit 106 ... Calculation circuit 108 ... Control circuit 110 …… Memory L …… Lens to be processed

Claims (1)

(57) [Claims] A carriage mounted on the main body so as to be vertically movable and laterally movable; a pair of lens shafts mounted on the carriage in a lateral direction; and a work clamped between the pair of lens shafts. An edge thickness measuring means for measuring an edge thickness of a lens peripheral portion corresponding to each radial direction; and an edge portion disposed above the lens axis so as to be rotatable about an axis parallel to the lens axis, and provided on the lens to be processed. A chamfering grindstone mounted on the main body so as to be able to move forward and backward, a swing arm member that rotatably supports and swings the chamfering grindstone, and suppresses swinging of the swing arm member. An elastic member for controlling the movement of the carriage up and down based on information from the edge thickness measuring means, and controlling the swinging of the swing arm member by the elastic member so that the surface of the corner portion on both sides of the lens to be processed. Control circuit for controlling the depth The eyeglass lens chamfer and wherein the door.