JP2021122893A - Lens processing device - Google Patents

Abstract

To provide a lens processing device reduced in cost and improved in handling property, which can measure a lens shape utilizing a module provided in the lens processing device.SOLUTION: False grindstones 5 and 6 are attached to both sides or one side of a grindstone 3 at a grindstone rotating shaft 2. A control device 31 moves a spectacle lens 30 in a shaft center direction of a chuck shaft 7 while bringing the lens into contact with the false grindstones 5 and 6. A micro switch 16 is configured to generate a detection signal at a timing when the spectacle lens 30 comes off from the false grindstones 5 and 6. The control device 31 is configured to: obtain a pulse count value of driving of a lens shift motor 25 at the time when the detection signal is generated when a front face and a rear face of the spectacle lens 30 respectively come off from the false grindstones 5 and 6; calculate positions of the front face and of the rear face of the spectacle lens 30 on the basis of the pulse count value; and measure a lens thickness on the basis of the positions of the front face and of the rear face of the spectacle lens 30 and a distance between both outsides of the false grindstones 5 and 6.SELECTED DRAWING: Figure 1

Description

The present invention relates to a lens processing apparatus capable of measuring a lens shape by utilizing the function of the lens processing apparatus.

When an unprocessed spectacle lens is attached to a spectacle frame, it is necessary to grind it according to the lens frame portion of the spectacle frame, and lens shape data for grinding is required.

The lens shape data includes a lens outer shape and a lens thickness shape. Normally, the lens outer shape is traced inside the lens frame of the spectacle frame with a contactor by a shape measuring instrument, and the displacement of the contactor is traced by a linear sensor, an encoder, etc. It was detected by the sensor of.

Further, the thickness shape of the spectacle lens is required to form a bevel on the peripheral surface of the lens in order to mount the spectacle lens on the lens frame. To measure the thickness shape of the spectacle lens, the peripheral edge of the spectacle lens is sandwiched by two contacts, the spectacle lens is rotated, and the displacement of both contacts is detected, or as shown in Patent Document 2, The peripheral edge of the spectacle lens was dropped into the V-groove, and the relative displacement between the spectacle lens and the V-groove in the direction of the axis of rotation when the spectacle lens was rotated was detected. In this case as well, sensors such as a linear sensor and an encoder have been used as the displacement detecting means.

In conventional lens shape measurement, a shape measuring device separate from the lens grinding device is required, and a delicate and expensive sensor is used for shape measurement, and such a sensor is used for adjustment and maintenance. There was a problem that caution was required and the failure rate was high.

Japanese Unexamined Patent Publication No. 6-297309 Japanese Unexamined Patent Publication No. 2001-9690

The present invention provides a lens processing apparatus capable of measuring a lens shape by using a module included in the lens processing apparatus, reducing costs and improving handleability.

The present invention includes a chuck shaft that supports a spectacle lens via a chuck, a swing frame that supports the chuck shaft and is swingable and movable in the axial direction of the chuck shaft, and the swing frame as an axis. A lens shift motor that moves in the direction of the center, a grindstone rotation shaft that is parallel to the chuck shaft, and a shape motor that moves the chuck shaft up and down via a conversion unit to bring the chuck shaft and the grindstone rotation shaft closer to each other. A micro switch interposed between the conversion unit and the chuck shaft, a grindstone detachably attached to the grindstone rotating shaft, and a control device are provided, and the grindstone rotating shaft is provided on both sides of the grindstone or independently. A pseudo-abrasive is attached, the lens shift motor and the shape motor are pulse motors, and the control device controls the lens shift motor and the shape motor by drive pulses input to the lens shift motor and the shape motor. The control device moves the spectacle lens in the axial direction of the chuck shaft in a state where the spectacle lens is in contact with the pseudo grindstone, and the microswitch is a time point when the spectacle lens is disengaged from the pseudo grindstone. The control device is configured to emit a detection signal to the lens shift motor drive pulse count value when the detection signal is emitted when the front surface and the back surface of the spectacle lens are deviated from the pseudo grindstone, respectively. Obtained, calculate the positions of the front surface and the back surface of the spectacle lens based on the pulse count value, and measure the lens thickness based on the positions of the front surface and the back surface of the spectacle lens and the distance between both outer sides of the pseudo grindstone. It relates to the configured lens processing apparatus.

Further, in the present invention, the pseudo grindstone is provided on both sides of the grindstone, and the pseudo grindstone has a flange portion having the same diameter as the grindstone and a small diameter cylindrical portion having a small diameter with respect to the flange portion, and outer surfaces of both flange portions. It relates to a lens processing apparatus whose flange is known.

Furthermore, the present invention relates to a lens processing apparatus in which the conversion unit is a rack / pinion mechanism.

According to the present invention, a chuck shaft that supports a spectacle lens via a chuck, a swing frame that supports the chuck shaft and is swingable and movable in the axial direction of the chuck shaft, and the swing frame. A lens shift motor that moves the lens in the axial direction, a grindstone rotation shaft parallel to the chuck shaft, and a shape that moves the chuck shaft up and down via a conversion unit so that the chuck shaft and the grindstone rotation shaft are separated from each other. A motor, a microswitch interposed between the conversion unit and the chuck shaft, a grindstone detachably attached to the grindstone rotating shaft, and a control device are provided, and the grindstone rotating shaft is provided on both sides of the grindstone or on both sides of the grindstone. A pseudo-abrasive is attached independently, the lens shift motor and the shape motor are pulse motors, and the control device uses a drive pulse input to the lens shift motor and the shape motor to cause the lens shift motor and the shape motor. The control device is configured to control, and the control device moves the spectacle lens in the axial direction of the chuck shaft in a state where the spectacle lens is in contact with the pseudo grindstone, and the microswitch is such that the spectacle lens is disengaged from the pseudo grindstone. The control device is configured to emit a detection signal at a certain time, and the control device counts the pulse of the lens shift motor drive when the detection signal is emitted when the front surface and the back surface of the spectacle lens are deviated from the pseudo grindstone, respectively. A value is acquired, the positions of the front surface and the back surface of the spectacle lens are calculated based on the pulse count value, and the lens thickness is measured based on the positions of the front surface and the back surface of the spectacle lens and the distance between both outer sides of the pseudo-abrasive stone. Since it is configured to be It exerts an excellent effect that the thickness data of the spectacle lens can be acquired at low cost.

It is a schematic block diagram of the lens processing apparatus which concerns on this Example. It is a control block diagram which concerns on this Example. It is operation explanatory drawing of this Example. It is operation explanatory drawing of this Example. It is operation explanatory drawing of this Example. It is operation explanatory drawing which shows the relationship between the spectacle lens and the pseudo grindstone in this Example.

Hereinafter, examples of the present invention will be described with reference to the drawings.

1 and 2 show a schematic configuration of the lens processing apparatus 1 according to the present embodiment.

A grindstone 3 is mounted on the grindstone rotating shaft 2, and the grindstone rotating shaft 2 is rotatably provided in a housing (not shown) of the lens processing apparatus 1. Further, the grindstone rotation shaft 2 is rotated by a grindstone motor (not shown). The grindstone 3 is removable from the grindstone rotation shaft 2, and the grindstone 3 is further composed of three grindstones 3a, 3b, and 3c. The number and combination of grindstones are appropriately selected depending on the conditions for processing the lens and the like.

FIG. 1 shows a state in which disk-shaped pseudo-grindstones 5 and 6 are further attached to both sides of the grindstone 3. The pseudo grindstones 5 and 6 are made of metal or a hard synthetic resin.

The pseudo grindstones 5 and 6 have a symmetrical shape, and flanges 5a and 6a are formed on the side in close contact with the grindstone 3, and small diameter cylindrical portions 5b and 6b are formed on the anti-grindstone side. Therefore, the outer peripheral surfaces of the flanges 5a and 6a have a stepped shape with a small diameter on the outside.

The outer diameters of the flanges 5a and 6a are equal to the outer diameter of the grindstone 3, and the outer diameters of the small diameter cylindrical portions 5b and 6b are smaller in radius by about 2 mm with respect to the flanges 5a and 6a.

The radius difference between the small-diameter cylindrical portions 5b and 6b with respect to the grindstone 3 is not limited to 2 mm as long as the radius difference is such that the microswitch returns, as will be described later. Further, the flanges 5a and 6a of the pseudo grindstones 5 and 6 and the small diameter cylindrical portions 5b and 6b may be integrated, respectively, or the flange and the small diameter cylindrical portion may be separated.

Further, the distance (outer dimension) between the outer surfaces (surfaces not in close contact with the grindstone 3) of the flanges 5a and 6a is known.

Further, the detection block 14 suppresses the subsequent downward displacement (radial displacement) of the spectacle lens 30 when the spectacle lens 30 is disengaged from the flange 5a and the flange 6a and the microswitch 16 is turned on. By doing so, the small-diameter cylindrical portion 5b and the small-diameter cylindrical portion 6b can be omitted. Therefore, the pseudo grindstones 5 and 6 may be only the flange 5a and the flange 6a portion having the same diameter as the grindstone 3.

The swing frame 20 having a chuck shaft 7 parallel to the grindstone rotation shaft 2 is supported by a swing shaft (not shown) parallel to the chuck shaft 7 and is vertically oriented around the swing shaft (FIG. 1). It is swingable in the vertical direction with respect to the paper surface of the paper and is slidable in the axial direction along the swing axis.

The swing frame 20 is provided with a lens motor 8 integrally with the swing frame 20, and the lens motor 8 and the chuck shaft 7 are connected via a gear row 9.

The chuck shaft 7 has a chuck 11 at the center, and the spectacle lens 30 can be chucked on the chuck 11.

The distance between the axis of the swinging shaft and the axis of the chuck shaft 7 is known, and the distance between the axis of the swinging shaft and the axis of the grindstone rotating shaft 2 is also known.

Due to the swing of the swing frame 20 about the swing shaft, the chuck shaft 7 (that is, the spectacle lens 30) is brought close to and separated from the grindstone 3.

One end of the chuck shaft 7 protrudes from the swing frame 20, and a copy mold 13 is detachably provided at the protruding tip, and the copy mold 13 comes into contact with the detection block 14. The detection block 14 has a guide plate 15 that can be moved in and out in the vertical direction, and a micro switch 16 that is turned ON / OFF by the vertical movement of the guide plate 15. The guide plate 15 functions as an actuator for operating the microswitch 16 and prevents an excessive load from acting on the microswitch 16.

Although the microswitch 16 is operated via the guide plate 15, the vertical displacement of the chuck shaft 7 may be directly detected by the microswitch 16.

A rack gear 17 that can move in the vertical direction is provided below the detection block 14, a detection block receiver 18 is provided at the upper end of the rack gear 17, and the detection block receiver 18 moves up and down integrally with the rack gear 17. It has become. A sphere 19 is interposed between the detection block 14 and the detection block receiver 18, and the detection block 14, the detection block receiver 18 and the sphere 19 are in point contact with each other. The sphere 19 may be omitted, and the upper surface of the detection block receiver 18 may be a spherical surface.

A shape motor 22 is connected to the rack gear 17 via a pinion gear 21, the pinion gear 21 is rotated by driving the shape motor 22, and the rack gear 17 moves up and down by the rotation of the pinion gear 21.

Here, the vertical movement of the rack gear 17 is transmitted to the chuck shaft 7 via the detection block 14, and the vertical movement of the chuck shaft 7 causes the swing frame 20 to swing. The rack gear 17 and the pinion gear 21 constitute a conversion unit that converts the rotation of the shape motor 22 into linear motion, and the conversion unit is a rack / pinion mechanism.

The conversion unit may be a nut / screw mechanism in which the rack gear 17 is a screw rod and the nut screwed into the screw rod is rotated by the shape motor 22.

A belt 24 is provided in parallel with the chuck shaft 7, and the belt 24 is rotated by a lens shift motor 25. The belt 24 and the swing frame 20 are connected to each other, and the lens shift motor 25 is connected. Moves the swing frame 20 in the left-right direction in FIG. 1 via the belt 24.

Thus, by driving the lens shift motor 25, the swing frame 20 moves, and the position of the spectacle lens 30 with respect to the grindstone 3 shifts.

Further, in FIG. 1, reference numeral 31 denotes a control device, which controls the rotation of the grindstone motor, the lens motor 8, and the shape motor 22. Here, at least the lens motor 8, the shape motor 22, and the lens shift motor 25 are motors capable of controlling the angle of rotation and the direction of rotation, such as a servo motor and a pulse motor. In this embodiment, a pulse motor capable of controlling the rotation angle and rotation direction by inputting a drive pulse is used.

The control device 31 will be described with reference to FIG.

In FIG. 2, the control device 31 has a calculation unit 33, a storage unit 34, a driver 35, and a pulse counter 36.

As the calculation unit 33, a CPU specialized for this device, a general-purpose CPU, an embedded CPU, a microprocessor, or the like is used. Further, as the storage unit 34, a semiconductor storage memory such as RAM, ROM, FlashROM, DRAM, a magnetic storage memory such as an HDD, an optical storage memory such as a CDROM, or the like is used.

The storage unit 34 contains a sequence program for controlling grinding operation and measurement operation, a motor drive program for driving and controlling the motor, and a position on the upper surface of the detection block receiver 18 based on a pulse count value, that is, the detection block. A program that calculates the position of 14 and calculates the position of the chuck shaft 7 of the spectacle lens 30 in the axial direction based on the pulse count value of the lens motor 8, and calculates the lens thickness from the position of the spectacle lens 30 in the axial direction. Various programs such as a program to be calculated are stored. Further, the grinding operation and the measurement operation are executed by executing various programs by the calculation unit 33.

The calculation unit 33 issues a motor drive command to the driver 35, and the driver 35 inputs a drive pulse to the lens motor 8 and the shape motor 22 based on the motor drive command. Further, the drive pulse is input to the pulse counter 36, the number of drive pulses is counted, the count value is input to the calculation unit 33, and further stored in the storage unit 34.

First, the lens processing for grinding the outer shape of the spectacle lens 30 by the lens processing device 1 will be outlined.

When processing the lens, the pseudo grindstones 5 and 6 may be incorporated from the beginning, or may be incorporated at the time of thickness measurement described later.

Here, when the outer shape data for grinding is acquired in advance and the unprocessed spectacle lens 30 is ground based on the outer shape data, a disk having a known diameter is used instead of the copying die 13. It is attached to the shaft 7. When grinding the outer shape of the spectacle lens 30, the grindstone 3a having a flat outer peripheral surface is used.

In a state where the grindstone 3 is rotated and the spectacle lens 30 is ground by the grindstone 3a, the shape motor 22 is controlled based on the shape data, and the detection block receiver 18 passes through the detection block 14 to the chuck shaft 7. Is raised and lowered, and the spectacle lens 30 is ground into a shape that matches the shape data. The control of the shape motor 22 by the calculation unit 33 is performed by controlling the drive pulse input from the driver 35 to the shape motor 22.

Next, a case where the thickness of the spectacle lens 30'after the outer shape grinding is measured will be described with reference to FIGS. 1, 3 to 6. When measuring the thickness, the rotation of the grindstone 3 is stopped.

The thickness of the spectacle lens 30'is measured continuously from the state where the chuck 11 is chucked or chucked by external grinding. The detection block receiver 18 pushes up the chuck shaft 7 via the detection block 14 so that the spectacle lens 30'is separated from the grindstone 3.

In this state, the weight of the swing frame 20, the chuck shaft 7 and the like (hereinafter, abbreviated as the weight of the swing frame 20) acts on the detection block 14, so that the guide plate 15 is pushed down and the micro The switch 16 is in the ON state.

The lens shift motor 25 is driven to move the spectacle lens 30'to the vicinity of the pseudo grindstone 6. The movement of the spectacle lens 30'by the lens shift motor 25 is performed by a drive pulse input to the lens shift motor 25, and the drive pulse input to the lens shift motor 25 is counted by the pulse counter 36.

The amount of movement of the spectacle lens 30 and the position after movement are calculated by the calculation unit 33 based on the pulse count value input from the pulse counter 36.

Further, the shape motor 22 lowers the detection block 14 via the rack gear 17 to bring the spectacle lens 30'in contact with the grindstone 3. When the spectacle lens 30'is in contact with the grindstone 3, the weight of the swing frame 20 is supported by the grindstone 3 via the spectacle lens 30'.

Further, the shape motor 22 is driven to lower the detection block 14 to the extent that the micro switch 16 is turned off. When the micro switch 16 is turned off, the OFF detection signal of the micro switch 16 is input to the calculation unit 33.

The spectacle lens 30'is moved to the right in the drawing by the lens shift motor 25 in a state where the spectacle lens 30'is in contact with the grindstone 3. Since the weight of the swing frame 20 remains supported by the grindstone 3, the OFF state of the microswitch 16 is maintained.

Further, when the spectacle lens 30'is moved to the right and the spectacle lens 30' is detached from the flange 6a (see FIGS. 4 and 6A), the spectacle lens 30'up to the small diameter cylindrical portion 6b. Fall. In the process of dropping, that is, in the process of displacement of the spectacle lens 30'in the radial direction, the weight of the swing frame 20 acts on the detection block 14 and the micro switch 16 is turned on. Therefore, the microswitch 16 detects the time when the spectacle lens 30'is detached from the flange 6a and emits a detection signal.

The ON signal of the micro switch 16 is input to the calculation unit 33, and the calculation unit 33 acquires the pulse count value of the lens shift motor 25 at the time of inputting the ON signal, and based on the pulse count value, the spectacle lens 30'. (Position in the axial direction of the chuck shaft 7) is calculated. The calculated position is the position of the surface (the surface on the left side in the drawing) of the spectacle lens 30'.

The spectacle lens 30'is further moved to the right by the lens shift motor 25. Further, when the ON signal is input to the calculation unit 33, the shape motor 22 lowers the rack gear 17 by at least the diameter difference between the flange 6a and the small diameter cylindrical portion 6b.

When the spectacle lens 30'contacts the small-diameter cylindrical portion 6b, the weight of the swing frame 20 is supported by the small-diameter cylindrical portion 6b, so that the microswitch 16 is turned on.

When the weight of the swing frame 20 acts on the detection block 14, the micro switch 16 is turned off, and when the weight of the swing frame 20 does not act, the micro switch 16 is turned on. You may.

Next, the shape motor 22 is driven to raise the rack gear 17, push up the rack gear 17 via the detection block 14, and separate the spectacle lens 30'from the grindstone 3 (see FIG. 1). ..

The lens shift motor 25 moves the spectacle lens 30'to the left in the figure, near the pseudo grindstone 5. The shape motor 22 is driven to bring the spectacle lens 30'in contact with the grindstone 3. In this state, the micro switch 16 is turned on.

The spectacle lens 30'is further moved to the left in the abutted state, and is dropped from the flange 5a to the small-diameter cylindrical portion 5b (see FIG. 6B).

Similar to the above, the microswitch 16 is turned off in the process of falling, and the position of the spectacle lens 30'when it is turned off (the back surface of the spectacle lens 30'in FIG. 6 (the right side surface in the drawing)). Position) is calculated.

The calculation unit 33 calculates the distance between the two positions based on the position of the spectacle lens 30'obtained from the pseudo grindstone 6 and the position of the spectacle lens 30'obtained from the pseudo grindstone 5.

Further, the thickness of the spectacle lens 30'can be measured by subtracting the outer dimension between the flanges 5a and 6a from the distance between the two positions.

Next, the lens motor 8 rotates the spectacle lens 30'by a required angle, for example, 5 °, and repeats the same operation as described above to measure the thickness of the spectacle lens 30'when rotated by 5 °. be able to. Further, by rotating the spectacle lens 30'360 ° in 5 ° steps and measuring the thickness in each 5 ° step, the thickness of the entire circumference of the spectacle lens 30'can be measured.

If the thickness measurement can be roughly performed, the step angle may be increased, and if detailed measurement is desired, the step angle may be decreased.

When the thickness measurement of the entire circumference of the spectacle lens 30'is completed, the thickness center can also be calculated, and data for forming a bevel on the peripheral surface of the spectacle lens 30' can be acquired.

When the peripheral surface of the spectacle lens 30'is ground to form a bevel, the grindstones 3b and 3c are used. It should be noted that the formation of the bevel can be continuously performed for the thickness measurement, the outer shape grinding of the spectacle lens 30, the thickness measurement, and the formation of the bevel can be continuously performed, and the processing time and the measurement time are shortened, and the work efficiency is reduced. Is improved.

When separating the grinding work process and the thickness measuring process, the grindstone 3 may be removed and a dummy disk may be incorporated between the pseudo grindstones 5 and 6, or the small-diameter cylindrical portion 5b and the small-diameter cylinder. One disk on which the portion 6b is formed may be incorporated into the grindstone rotating shaft 2.

As described above, in this embodiment, only the pseudo grindstones 5 and 6, which are simple parts, are added to the conventional lens processing apparatus, and only the basic modules (components) of the lens processing apparatus are used to form the lens. The thickness shape can be measured. Therefore, since an expensive sensor is not used and a delicate sensor is not used, the manufacturing cost can be reduced and the workability and maintainability can be improved.

1 Lens processing device 2 Whetstone rotation shaft 3 Whetstone 5 Pseudo grindstone 5a Flange 5b Small diameter cylindrical part 6 Pseudo grindstone 6a Flange 6b Small diameter cylindrical part 7 Chuck shaft 8 Lens motor 14 Detection block 16 Micro switch 17 Rack gear 20 Swing frame 22 Shape motor 25 Lens shift motor 30 Eyeglass lens 31 Control device 33 Calculation unit 34 Storage unit 35 Driver 36 Pulse counter

Claims (3)

A chuck shaft that supports the spectacle lens via a chuck, a swing frame that supports the chuck shaft and can swing and move in the axial direction of the chuck shaft, and a swing frame that moves in the axial direction. A lens shift motor for causing the lens shift motor, a grindstone rotating shaft parallel to the chuck shaft, a shape motor that moves the chuck shaft up and down via a conversion unit, and causes the chuck shaft and the grindstone rotation shaft to move apart from each other, and the conversion unit. A micro switch interposed between the chuck shaft, a grindstone detachably attached to the grindstone rotating shaft, and a control device are provided, and pseudo grindstones are attached to the grindstone rotating shaft on both sides of the grindstone or independently. The lens shift motor and the shape motor are pulse motors, and the control device is configured to control the lens shift motor and the shape motor by a drive pulse input to the lens shift motor and the shape motor. The control device moves the spectacle lens in the axial direction of the chuck shaft in a state where the spectacle lens is in contact with the pseudo grindstone, and the microswitch outputs a detection signal when the spectacle lens comes off the pseudo grindstone. The control device acquires the pulse count value of the lens shift motor drive when the detection signal is emitted when the front surface and the back surface of the spectacle lens deviate from the pseudo grindstone, respectively, and the control device obtains the pulse count value. A lens configured to calculate the positions of the front and back surfaces of the spectacle lens based on the pulse count value and measure the lens thickness based on the positions of the front and back surfaces of the spectacle lens and the distance between both outer sides of the pseudo-grind. Processing equipment. The pseudo grindstone is provided on both sides of the grindstone, and the pseudo grindstone has a flange portion having the same diameter as the grindstone and a small diameter cylindrical portion having a small diameter with respect to the flange portion, and the distance between the outer surfaces of both flange portions is known. The lens processing apparatus according to claim 1. The lens processing apparatus according to claim 1, wherein the conversion unit is a rack / pinion mechanism.

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