JPH0655130U - Eyeglass lens frame shape measuring device - Google Patents

Abstract

(57) [Abstract] [Purpose] It is an object of the present invention to provide an eyeglass lens frame shape measuring apparatus which enables accurate positioning of a tracing stylus and realizes accurate shape measurement. [Structure] An outer cylinder 65 that guides the cylindrical portion of the stylus 30 in the axial direction, a cage 49 that is made up of rolling elements and a retainer, is provided inside the outer cylinder 65, and a stylus head 32 at one end, Extending in the axial direction of the cylindrical portion of the stylus 30,
A stylus 30 having an annular zone 30b is provided so as to penetrate through the inside of the cage 49 and be closer to the stylus head 32 than the cage 49. After the measurement, the stylus 30 descends due to its own weight. At that time, the ring zone 30b hits the upper end of the cage 49 and pushes down the cage 49. This allows the cage 49
However, even if the cage 49 sticks to the outer cylinder 65 and does not descend due to the viscosity of the lubricating oil, the cage 49 is prevented from remaining in the upper position. Therefore, when the measurement is performed again next time, the stylus head 32 is accurately positioned in the frame groove of the spectacle lens frame, and accurate shape measurement can be performed.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a spectacle lens frame shape measuring device for measuring a spectacle lens frame shape by moving the probe along the frame groove of the spectacle lens frame or the outer periphery of the spectacle frame template, and particularly to smooth vertical movement of the probe. The present invention relates to an eyeglass lens frame shape measuring device that enables the above.

[0002]

[Prior art]

 Conventionally, in a spectacle lens frame shape measuring device, as disclosed in, for example, Japanese Patent Publication No. 4-55824, an abacus ball-shaped frame measuring probe and a measuring unit for contacting it with a spectacle frame template are used. There was a device with a measuring end that

[0003]

[Problems to be solved by the device]

 However, this conventional device is premised on two-dimensional measurement, and there is a problem that the shape of the measuring end is complicated and the probe itself is very heavy.

On the other hand, in order to frame the spectacle lens with high precision, precise measurement of the spectacle lens frame shape is required, and for that purpose, three-dimensional measurement is required. In that case, the condition required for the measuring element is that it closely follows the frame groove of the spectacle lens frame or the outer periphery of the spectacle frame template, and in particular that it can move smoothly in the axial direction of the measuring element.

For example, if the probe is heavy, the contact pressure is excessively applied to the eyeglass lens frame or the eyeglass frame template, so that the eyeglass lens frame or the eyeglass frame template is deformed or the true eyeglass lens frame shape is measured. There is a problem that you can not.

By the way, in order to provide the axis of the tracing stylus in the vertical vertical direction and to smoothly move the tracing stylus in the vertical direction with accuracy, a cylindrical guide means is formed on the outer periphery of the spindle of the tracing stylus. In order to smooth the movement of the spindle of the tracing stylus with respect to the guide means, an interposition such as a rolling bearing is provided between the spindle of the tracing stylus and the cylindrical guide means. Means are preferably provided. In addition, as one of the automation of the measuring device, a push-up means connected to a motor or the like is provided at the lower end of the spindle of the tracing stylus to move the spindle of the tracing stylus upward and downward to move the frame groove of the spectacle lens frame. Alternatively, it is conceivable to add a structure for automatically positioning the tracing stylus on the outer periphery of the eyeglass frame template.

In the case of the above configuration, if the fitting accuracy of the intervening means with respect to the support shaft or the guide means of the probe is strict, the free up and down movement of the probe at the time of measurement may be hindered. In addition, although there is no problem because the raising of the tracing stylus before the measurement is performed by the push-up means, the descent of the tracing stylus after the measurement depends on the weight of the tracing stylus, which causes a problem that it does not descend well.

In order to avoid such a situation, it is conceivable to loosen the fitting accuracy of the interposition means with respect to the support shaft of the probe and the guide means. In such a case, if the horizontal pressing force from the spectacle lens frame or the spectacle frame template against the probe disappears after the measurement, the probe descends by its own weight, but the intervening means sticks to the guide means due to the viscosity of the lubricating oil. , It may not fall. In this case, when performing the measurement again, if the support shaft of the probe rises with a slight inclination with respect to the axial direction of the intervening means or guide means, no slip occurs between the support shaft of the probe and the intervening means. Therefore, when the intervening means reaches the uppermost position, the intervening means may prevent further lifting of the support shaft of the stylus, and as a result, the stylus may be blocked by the frame groove of the ophthalmic lens frame or the eyeglass frame template. The problem is that it cannot be positioned on the outer circumference.

The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide a spectacle lens frame shape measuring device which enables accurate positioning of a tracing stylus and realizes accurate shape measurement. To aim.

[0010]

[Means for Solving the Problems]

 In order to solve the above-mentioned problems, the present invention has an outer cylinder for guiding the measuring element in the axial direction, an intermediary means provided inside the outer cylinder and comprising a rolling element and a retainer, and a measuring element at one end. The eyeglass lens frame-shaped measuring device is characterized in that it has a tracing stylus support shaft extending in the axial direction of the tracing stylus, penetrating inside the intervening means, and having a projection on the tracing stylus side from the interposing means. Provided.

[0011]

[Action]

 In the above configuration, when the horizontal pressing force from the spectacle lens frame or the spectacle frame template against the tracing stylus disappears after the measurement, the tracing stylus descends by its own weight. It hits the top of the means and pushes down the intervening means. This prevents the intervening means from staying at the upper position even if the intervening means sticks to the guide means due to the viscosity of the lubricating oil and does not descend. Therefore, when the measurement is performed again next time, the tracing stylus can be accurately positioned in the frame groove of the spectacle lens frame or the outer periphery of the spectacle frame template, and accurate shape measurement can be performed.

[0012]

【Example】

 An embodiment of the present invention will be described below with reference to the drawings. 2 and 3 show the entire configuration of the spectacle lens frame shape measuring device, FIG. 2 is a perspective view of the device, and FIG. 3 is a side view of the device as seen from the direction A in FIG. In these drawings, the holding means for the spectacle lens frame is not shown in order to avoid complexity.

The present apparatus is equipped with a measuring unit 1 for measuring the shape of the frame groove of the spectacle lens frame Fr which is held so as not to move to a predetermined position by a spectacle lens frame holding means (not shown). This measuring unit 1 is provided with a U-shaped rotary table 2 which is rotated in the Θ direction by a motor 6 via a timing pulley 3, a timing belt 4 and a timing pulley 5 attached to the lower end surface thereof. Driven. The angle of this rotation is detected by the rotary encoder 9 connected to the timing belt 4 via the timing pulley 8. The motor 6 and the rotary encoder 9 are fixed to a substrate 10 (only a part of which is shown in FIG. 2 so that other parts of the measuring device can be easily seen) of the measuring device, and the timing pulley 3 and the rotary base 2 are shown in FIG. It is rotatably supported on the base plate 10 by bearings not shown.

The turntable 2 of the measuring unit 1 is composed of two side plates 11 and 12 and a rectangular center plate 13 connecting the both side plates. Two slide guide shafts 14 and 15 are fixed in parallel between the side plate 11 and the side plate 12. A slide plate 16 installed horizontally along the slide guide shafts 14 and 15 is slidably guided in the R direction. For this guide, the slide plate 16 is provided on its lower surface with slide guides 17 and 18 having rotatable rollers. These slide guides 17 and 18 are configured such that the surfaces having rollers face each other and sandwich the slide guide shafts 14 and 15.

A constant load spring 20 acts on the slide plate 16 in the sliding direction R, and the slide plate 16 is pulled toward one side plate 12. As shown in FIG. 3, one end of the constant force spring 20 is wound around a bushing 21, and the bushing 21 is fixed to the side plate 12 via a bracket 23. The other end of the constant load spring 20 is attached to a part of the slide plate 16. The constant load spring 20 has the function of constantly pressing a stylus, which will be described later, into the frame groove of the ophthalmic lens frame Fr.

The amount r of movement of the slide plate 16 in the R direction is measured by a reflection type linear encoder 24 as a displacement measuring scale. The linear encoder 24 includes a scale 25 extending between the side plate 11 and the side plate 12 of the turntable 2, a detector 26 fixed to the slide plate 16 and moving along the scale 25, an amplifier 27, and A flexible cable 28 connecting the amplifier 27 and the detector 26. The amp 27 is attached to a bracket 29 fixed to the side plate 12.

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

The slide plate 16 holds a stylus 30 as a probe. The stylus 30 is rotatably and rotatably supported in a sleeve 31 fixed to the slide plate 16 by a cage (to be described later) so as to be movable in the vertical direction (Z direction). The stylus 30 has an abacus ball-shaped head 32, and the head 32 is fitted into the frame groove of the spectacle lens frame Fr by the operation of the constant load spring 20, and the rotary table 2 is rotated to rotate the spectacle lens frame Fr. Move along the frame groove. The structure of the cage will be described later with reference to FIGS. The structure of the stylus 30 will be described later with reference to FIGS.

The stylus 30 moves in the radial direction of the spectacle lens frame Fr corresponding to the shape of the spectacle lens frame Fr. The moving amount in the radial direction, that is, the moving amount r in the R direction is measured by the linear encoder 24 via the sleeve 31 and the slide plate 16 as described above.

Further, the stylus 30 moves in the Z direction corresponding to the curve of the spectacle lens frame Fr. The Z-axis measuring device 33 formed as a displacement measuring scale detects the amount of movement in the Z direction. As shown in FIG. 4, the Z-axis measuring device 33 includes a charge coupled device (CCD) line image sensor 34 and a light emitting diode (LED) 35 as a light source, and is attached to the slide plate 16.

The CCD line image sensor 34 and the LED 35 are arranged to face each other. Since the stylus 30 moves up and down between them according to the curve of the spectacle lens frame Fr, the boundary between the shadow of the stylus 30 blocked by the stylus 30 and formed on the CCD line image sensor 34 and the bright part also moves up and down. To do. Therefore, the displacement z of the stylus 30 in the Z direction can be measured by detecting the distance from the edge of the measurement surface of the CCD line image sensor 34 to this boundary.

Further, as shown in FIG. 3, the present measuring device is provided with a motor rotation limit mechanism 36 for stopping the motor 6 after the shape measurement. This mechanism is formed by a rotation limit L fitting 37 fixed to the side surface of the timing pool 3, a vertically extending shield rod 38 operated by the L fitting 37, and a horizontal rod formed integrally with the shield rod 38. The shield plate 39 extending in the direction, two springs (not shown) that movably support the shield plate 39 and the shield rod 38 by pulling the shield plate 39 and the shield rod 38 from both horizontal sides, and cooperate with the shield plate 39. It is composed of photo interrupters 41a and 41b. The photo interrupters 41a and 41b and the two springs are attached to the substrate 10.

A signal obtained by the rotation limit L fitting 37 pressing the shield rod 38 and the shield plate 39 passing through the photo interrupters 41 a and 41 b to shield the light is input to a control circuit described later, and the motor 6 Stops.

Further, as shown in FIG. 3, the present measuring apparatus further includes an initial R direction moving mechanism 50 for moving the stylus 30 to a predetermined position in the R direction (almost center position of the lens frame) before shape measurement. I have it. This mechanism includes an R direction motor 51, which is a stepping motor fixed to the side plate 12, a pulley 52 attached to the R direction motor 51, a pulley 53 attached to the side plate 11, a pulley 52 and a pulley 53. A wire 54 suspended on the wire 54, a coil spring 55 and a stopper 56 attached in the middle of the wire 54, and an abutting member fixed to the slide plate 16 and constantly abutting the stopper 56 from the right in FIG. 57 and 57.

First, at the end of the previous shape measurement, the stopper 56 is moved to a predetermined origin position near the pulley 53 by the driving of the R direction motor 51, and is held at that position. Therefore, before the shape measurement, The slide plate 16 is also close to the pulley 53. When the R direction motor 51 is energized with a predetermined number of pulse currents, the stopper 56 moves leftward in FIG. 3, and accordingly, the contact member 57 also moves leftward by the action of the constant force spring 20. Move to. Therefore, the slide plate 16 moves leftward. When the slide plate 16 is almost moved to the predetermined position, the R-direction motor 51 is stopped, and the head 32 of the stylus 30 is raised to a predetermined height by the action of the initial Z-direction moving mechanism 60 described later. After that, the R-direction motor 51 further rotates in the same direction to move the stopper 56 to the left in FIG. 3, so that the contact member 57 also moves to the left and the slide plate 16 also moves to the left. As a result, when the head 32 of the stylus 30 contacts the previously fixed eyeglass lens frame Fr, the leftward movement of the slide plate 16 and the contact member 57 is stopped, but the stopper 56 is further moved to a predetermined position. To the left, the power supply to the R-direction motor 51 is stopped.

After that, the shape measurement is performed, and after the shape measurement is completed, the R-direction motor 51 rotates in the opposite direction, and the stopper 56 is moved to the predetermined origin position near the pulley 53 as described above. Held in position. Therefore, the slide plate 16 is also held at a position close to the pulley 53.

FIG. 4 is a side view showing the initial Z-direction moving mechanism 60 in an enlarged view of the upper portion of FIG. This mechanism is fixed to the slide plate 16, and the structure is such that a Z-direction motor 61 composed of a stepping motor, a gear portion 62 driven by this Z-direction motor 61, and a Z-direction motor 61 are passed through and a gear is provided. The push-up shaft 63 moves in the vertical direction in FIG. 4 by the portion 62, and the origin sensor 64 that operates by the lower portion of the push-up shaft 63.

Normally, the push-up shaft 63 is stopped at a position where the origin sensor 64 is turned on, and when a predetermined number of pulse currents are applied to the Z-direction motor 61, the push-up shaft 63 rises and pushes up the stylus 30. The Z-direction motor 61 stops at a predetermined position of the stylus 30 and holds that position until the Z-direction motor 61 is energized in the opposite direction. When electricity is applied in the opposite direction, the push-up shaft 63 descends, the origin sensor 64 is turned on, and the energization of the Z-direction motor 61 is stopped.

FIG. 5 is an enlarged side sectional view showing the cage 49, the lower end of the stylus 30, and the upper end of the push-up shaft 63. That is, the cylindrical outer cylinder 65 is provided inside the sleeve 31 fixed to the slide plate 16, and the cage 49 is provided inside the outer cylinder 65. The structure of the cage 49 will be described with reference to FIG.

FIG. 6 is a perspective view of the cage 49. The cage 49 includes a large number of balls 49a to 49n and a cylindrical retainer 49p that rotatably retains these balls, and each ball 49a to 49n protrudes inside and outside the retainer 49p. Is configured.

Returning to FIG. 5, a cylindrical portion of the stylus 30 is provided inside the cage 49, and an outer diameter of the cylindrical portion is formed by an inner diameter of the cage 49 (each inner protruding apex of the balls 49 a to 49 n). It is set to be slightly smaller than the diameter of the cylinder). Specifically, a difference of about 1% in diameter is provided between them. Due to this slight gap, slippage occurs between the cylindrical portion of the stylus 30 and the cage 49.

Further, a hole 30a is provided on the lower end surface of the stylus 30. The hole 30a is formed in a tapered shape centering on the axis of the cylindrical portion of the stylus 30. On the other hand, the push-up shaft 63 is eccentrically arranged at a position facing the hole 30a. That is, when the push-up shaft 63 rises, the tip projection 63a at the axial center of the push-up shaft 63 is arranged so as to abut the tapered portion of the hole 30a. The tip protrusion 63a is a protrusion having a smooth tip and has, for example, a spherical shape.

With such an eccentric arrangement, when the push-up shaft 63 pushes up the stylus 30, the stylus 30 is slightly tilted with respect to the longitudinal direction of the cage 49, and the cylindrical portion of the stylus 30 and the cage 49 are partly in close contact with each other. The condition is reached and the slippage between the two is eliminated. Therefore, when the stylus 30 rises, the cage 49 also rises by an amount which is exactly half the amount of the rise.

Furthermore, in the middle of the cylindrical portion of the stylus 30, a ring zone 30b having an outer diameter that is larger than the outer diameter of the cylindrical portion and smaller than the inner diameter of the outer cylinder 65 is provided. When the cage 49 is at the predetermined lower end position (the position shown in FIG. 1) and the stylus 30 is at the predetermined lower end origin position (the position shown in FIG. 1), the axial position of the annular zone 30b is The position is such that the lower end of the ring zone 30b contacts the upper end of the cage 49.

FIG. 7 is a partial sectional view showing the structure of the stylus 30 provided with such an annular zone 30b, and FIG. 1 is a sectional view showing the positional relationship between the stylus 30 and peripheral components. Is.

Next, the operation of the eyeglass lens frame shape measuring device configured as described above will be described. First, when the spectacle lens frame Fr is fixedly held by the holding means, and the measurement start switch (not shown) is turned on, the R direction motor 51 is rotated by the instruction of the control circuit (not shown) to the origin position near the pulley 53. The existing stylus 30 horizontally moves to the center of one of the spectacle lens frames Fr.

Next, the Z-direction motor 61 rotates, the push-up shaft 63 rises, and accordingly the stylus 30 rises, and the head 32 of the stylus 30 reaches the predetermined Z-direction position. At this time, the cage 49 also rises from the lowest position by half of the stylus 30 rise. When the rotation of the Z-direction motor 61 is stopped, both the stylus 30 and the cage 49 stay in these raised positions.

Next, the R direction motor 51 further rotates in the same direction as the above rotation, the stopper 56 is sent to a predetermined position, and the rotation of the R direction motor 51 is stopped. Meanwhile, the contact member 57 follows the stopper 56 by the action of the constant load spring 20, but when the head 32 of the stylus 30 contacts the spectacle lens frame Fr, the follow-up is stopped and the contact member 57, the slide The movement of the plate 16 and the like is stopped.

Next, the Z-direction motor 61 rotates in the direction opposite to the above rotation, the push-up shaft 63 descends, and the rotation of the Z-direction motor 61 is stopped when the origin sensor 64 is detected to be ON. At this time, the head 32 of the stylus 30 contacts the spectacle lens frame Fr, and the head 32 is subjected to a reaction in the direction perpendicular to the axial direction. On the other hand, the stylus 30 and the cage 49 are slightly inclined, and the cage 49 is partially in close contact with each other, and there is no slip between the two. Therefore, the cage 49 remains in its raised position even if the thrust-up shaft 63 descends.

Next, the motor 6 is rotated so that the stylus 30 moves in the direction opposite to the Θ direction for measurement. Then, when the rotation limit L fitting 37 pushes the shield rod 38 and the shield plate 39 blocks the incident light to the photo interrupter 41a or the photo interrupter 41b, the rotation of the motor 6 is stopped. The movement of the stylus 30 in the opposite direction is performed so that the tip of the head 32 of the stylus 30 is brought into complete contact with the bottom of the frame groove of the spectacle lens frame Fr.

Next, the motor 6 is rotated in the direction opposite to the rotation direction (θ direction for measurement). When the stylus 30 reaches the measurement start position, the measurement of the shape of the frame groove of the spectacle lens frame Fr is started. The amount of movement of the stylus 30 in the radial direction is detected by the linear encoder 24 as the amount of movement r of the slide plate 16 in the R direction, and the amount of vertical movement is determined by the CCD line image sensor 34 as the amount of movement z of the stylus 30 in the Z direction. To be detected. At that time, the movement amount r and the movement amount z are sequentially stored in the memory in correspondence with the angle signal θ of the rotary encoder 9. The three-dimensional shape of the spectacle lens frame Fr is obtained based on these data θ, r, z.

During such shape measurement or movement of the stylus 30 in a direction opposite to the measurement Θ direction, the head 32 of the stylus 30 follows the shape of the frame groove of the spectacle lens frame Fr. Although the cage 49 must move smoothly in the Z direction, as described above, the cage 49 remains in the raised position, so there is room to descend, and when the stylus 30 descends, it descends by half of the descending amount. The cage 49 has no adverse effect on the lowering of the stylus 30. As a result, the stylus 30 moves up and down smoothly, and an accurate measured value in the Z-axis direction can be detected.

Then, the rotary table 2 makes one rotation, the rotation limit L fitting 37 pushes the shielding rod 38, the motor 6 stops, and the above-described shape measurement also stops. After the shape measurement is stopped, the slide plate 16 is returned to the position closer to the pulley 53 by driving the R direction motor 51 as described above. As a result, the reaction of the head 32 of the stylus 30 from the spectacle lens frame Fr in the direction perpendicular to the axial direction is eliminated, so that the close contact between the cylindrical portion of the stylus 30 and the cage 49 is eliminated, and the cylindrical column of the stylus 30 is eliminated. There is a possibility of slippage between the parts and the cage 49. On the other hand, when the cage 49 is stuck to the outer cylinder 65 due to the viscosity of the lubricating oil, the stylus 30 slides with respect to the cage 49 and only the stylus 30 tries to descend due to its own weight. At this time, since the lower end of the ring zone 30b of the stylus 30 abuts on the upper end of the cage 49, the cage 49 is pushed down and returns to the position shown in FIG.

Therefore, when the measurement is started again next time, the cage 49 is at the predetermined lower end position, so that the cage 49 does not prevent the stylus 30 from rising, and the head 32 of the stylus 30 is The spectacle lens frame Fr is accurately positioned in the frame groove.

Although the tracing of the frame groove of the spectacle lens frame Fr by the head 32 of the stylus 30 has been described in the above embodiment, the concave portion 30c of the stylus 30 as shown in FIG. You may make it trace the outer periphery of.

[0046]

[Effect of device]

 As described above, in the present invention, the protrusion of the tracing stylus support shaft hits the upper end of the interposition means or pushes down the interposition means. This prevents the intervening means from staying at the upper position even if the intervening means sticks to the guide means due to the viscosity of the lubricating oil and does not descend. Therefore, when the measurement is performed again next time, the tracing stylus can be accurately positioned in the frame groove of the spectacle lens frame or the outer periphery of the spectacle frame template, and accurate shape measurement can be performed.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a relationship between a stylus and peripheral components.

FIG. 2 is a perspective view showing an overall configuration of a spectacle lens frame shape measuring device.

3 is a side view of the eyeglass lens frame shape measuring device viewed from the direction A in FIG.

FIG. 4 is a side view showing an enlarged view of the upper portion of FIG.

FIG. 5 is an enlarged side sectional view showing a cage, a lower end of a stylus, and an upper end of a push-up shaft.

FIG. 6 is a perspective view of a cage.

FIG. 7 is a partial cross-sectional view showing the structure of a stylus provided with a ring zone.

[Explanation of symbols]

 16 slide plate 30 stylus 30b ring zone 32 head 49 cage 60 initial Z-direction moving mechanism 65 outer cylinder

Claims (3)

[Scope of utility model registration request] 1. A spectacle lens frame shape measuring device for measuring a spectacle lens frame shape by moving the probe along the frame groove of the spectacle lens frame or the outer circumference of the spectacle frame template, and guiding the probe in an axial direction. An outer cylinder, a rolling element and a retainer, and an interposition means provided inside the outer cylinder, and the measuring element at one end, which extends in the axial direction of the measuring element,
A spectacle lens frame shape measuring device, comprising: a tracing stylus support shaft that is penetrated inside the interposing means and has a protrusion on the stylus side from the interposing means. 2. The protrusion of the tracing stylus support shaft contacts the upper end of the interposition means when the intervening means is at a predetermined lower end position and the tracing stylus support shaft is at a predetermined lower end origin position. The eyeglass lens frame shape measuring device according to claim 1, wherein the eyeglass lens frame shape measuring device is provided at such a position. 3. The spectacle lens frame according to claim 1, wherein the protrusion of the tracing stylus support shaft is a stepped ring zone having an outer shape having a value larger than the outer diameter of the tracing stylus support shaft. Shape measuring device.