JPH0624852U - Eyeglass lens holding device - Google Patents

Abstract

(57) [Abstract] [Object] In a spectacle lens holding device for holding a spectacle lens at the time of edging, the lens can be easily and surely attached to a clamp shaft. [Structure] When the lens 1 is fixed, the biting teeth 42 of the lens holding member 4 bite into the seal 5. During the grinding process, a resistance force that causes a deviation between the lens holding member 4 and the seal 5 works due to the force that the lens holding member 4 tries to rotate the lens 1 and the torque that the lens 1 receives from the grindstone. However, since the rotation direction side surface 42a of the biting tooth 42 is formed substantially perpendicular to the rotation direction, the resistance force can be received most efficiently. Therefore, it is possible to surely prevent the axial displacement of the lens 1.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an eyeglass lens holding device for holding an eyeglass lens, and more particularly to an eyeglass lens holding device for holding an eyeglass lens during edging.

[0002]

[Prior art]

 Generally, when edging a spectacle lens, the spectacle lens is clamped from both front and back sides by a clamp shaft, and the spectacle lens is rotationally controlled in the circumferential direction. At this time, as a method of fixing the clamp shaft and the spectacle lens, there are mainly three methods called a suction method, a mold method, and a block method. In these methods, usually, only the lens surface and the clamp shaft are fixed.

In the suction method, a bowl-shaped rubber member having a radius of curvature deeper than the lens surface is pressed against the lens surface, the lens and the rubber member are connected by using suction force, and the rubber member is clamped. It is a method of connecting the shafts.

The mold method is a method in which a mold is applied to the front surface of the lens, alloy metal or wax, which is a low-melting point substance, is injected into this mold in a liquid state, and the mold is removed when it is hardened at room temperature. Is. When the low melting point substance is solidified, the connecting member is also fixed at the same time, and the clamp shaft and the lens are connected and fixed via this connecting member.

The block method is a method in which a flat rubber member is attached to the front surface of the lens and the clamp shaft is attached from the opposite side.

[0006]

[Problems to be solved by the device]

 However, since the suction method and the block method both use a rubber member, there is a risk of deformation due to the torque applied to the lens during the edging process. For this reason, there was a concern that axis misalignment would occur.

Further, in the molding method, since a mold has to be formed every time the lens is replaced, it takes time and labor and the production efficiency cannot be said to be good. The present invention has been made in view of the above circumstances, and an object thereof is to provide a spectacle lens holding device capable of easily and surely attaching a lens to a clamp shaft.

[0008]

[Means for Solving the Problems]

 In order to solve the above problems, the present invention provides a spectacle lens holding device for holding a spectacle lens during edging of a spectacle lens, in which the spectacle lens is clamped from both front and back directions in a specific rotation direction. The rotating clamp shaft, the elastic seal attached to at least one of the front and back surfaces of the spectacle lens, and the tip of the elastic seal side clamp shaft are attached to the elastic seal while pressing the elastic seal. The lens holding member for holding the spectacle lens, and the contact surface of the lens holding member with the elastic seal has a plurality of teeth that bite into the elastic seal when rotated in the specific rotation direction. An eyeglass lens holding device is provided which is characterized in that it is formed.

[0009]

[Action]

 An elastic seal is attached to at least one of the front surface and the back surface of the spectacle lens, and a lens holding member is attached to the tip of the clamp shaft on the elastic seal side to hold the spectacle lens while pressing the elastic seal. In this state, when the clamp shaft is rotated so as to rotate the spectacle lens in a specific rotation direction, the teeth formed on the contact surface of the lens holding member with the elastic seal bite into the elastic seal. As a result, the displacement between the elastic seal and the lens holding member is prevented.

[0010]

【Example】

 An embodiment of the present invention will be described below with reference to the drawings. FIG. 2 is a diagram showing a configuration of a main part of the eyeglass lens edging machine. The lens 1 is a plastic lens whose main component is diethylene glycol bisallyl carbonate, and its front side surface 1a and back side surface 1b are clamped and fixed by clamp shafts 2 and 3. However, a lens holding member 4 is attached to the tip end portion of the clamp shaft 2 via a chuck 8, and a seal 5 is attached to the front side surface 1a of the lens 1. On the other hand, the clamp shaft 3 has its tip portion 3a directly connected to the back side surface 1b of the lens 1. The clamp shafts 2 and 3 are rotationally controlled at the same speed in the arrow X and Y directions by a driving device (not shown).

A plurality of biting teeth, which will be described later, are formed on the surface of the lens holding member 4 on the side of the lens 1 so as to engage with the seal 5. The seal 5 is made of an elastic material such as rubber, and this elastic material contains a fiber material. This enhances the durability against twisting and pulling. The seal 5 is attached to the front side surface 1a of the lens 1.

The lens 1 fixed by the clamp shafts 2 and 3, the lens holding member 4, and the seal 5 in this manner is subjected to edging by the grindstone 6. The grinding surface 6a of the grindstone 6 is coated with an abrasive such as sintered diamond. The grindstone 6 is rotated by a shaft 7. The shaft 7 is rotationally controlled in the arrow Z direction, which is the same direction as the arrows X and Y, by a drive device (not shown). Therefore, the edge surface 1c of the lens 1 and the grinding surface 6a of the grindstone 6 rub while moving in opposite directions.

FIG. 3 is a perspective view showing the structure of the lens holding member 4. The lens holding member 4 is composed of a pressing portion 43 for pressing the lens 1 and a mounting portion 44 for mounting on the clamp shaft. The pressing portion 43 and the mounting portion 44 are both formed in a cylindrical shape having the same inner diameter, and the outer diameter of the pressing portion 43 is larger than that of the pressing portion 43.

Biting teeth 42 are formed on the seal contact surface 41 of the pressing portion 43 at equal intervals along the circumferential direction. The individual teeth 42 are formed from the outer edge of the seal contact surface 41 toward the center. Further, a notch 45 serving as a positioning index at the time of mounting is formed on a part of the side surface of the pressing portion 43. On the other hand, a tapered portion 44a is formed near the end of the mounting portion 44.

FIG. 4 is a diagram showing a specific shape of the biting teeth 42. The biting tooth 42 has a substantially triangular cross-section, and its tip 42c is chamfered by a width L (0.2 mm). Further, the height M of the biting teeth 42 and the maximum width N between the adjacent sides 42a, 42b are both formed to be 1 mm. The chamfer width L, height M, and maximum width N are appropriately changed depending on the material of the lens holding member 4, the processing conditions, and the like. In general spectacle lenses, the chamfer width L is preferably 0.05 mm to 0.5 mm, and the height M and the maximum width N are preferably 0.2 mm to 5 mm.

The surface 42a on the rotation direction side of the biting tooth 42 and the other surface 42b are formed so that the angles θ1 and θ2 with respect to the horizontal direction in the drawing are θ1> θ2. By doing so, the tip portion 42c is inclined in the direction of rotation, so that the seal 5 easily bites. The angles θ1 and θ2 are appropriately determined according to the height M and the maximum width N of the biting teeth 42, the strength of the seal 5, and the like. In some cases, θ1> 90 ° may be satisfied. Here, θ1 = 90 ° and θ2 = 45 ° are set.

FIG. 5 is a sectional view taken along the line AA of FIG. As can be seen from the figure, the seal contact surface 41 is formed to have a certain radius of curvature. The radius of curvature is formed so as to be smaller than the radius of curvature of the front surface 1a of the lens 1. As a result, when the lens holding member 4 is brought into contact with the lens 1 via the seal 5, the edge portions 41a, 41b of the seal contact surface 41 and the like come into deep contact with the seal 5 to more firmly fix the lens 1. it can.

The radius of curvature of the seal contact surface 41 is preferably prepared according to the shape of the front side surface 1a of the lens 1 to be processed, but there are several types based on the lens base curve. If they are prepared separately, they can fit most lenses.

FIG. 6 is a diagram showing a method of connecting the lens holding member 4 having such a configuration to the clamp shaft 2. A chuck 8 having three claws 8a, 8b, 8c is provided at the tip of the clamp shaft 2. The lens holding member 4 is inserted from the tip of the mounting portion 44 between the claws 8a, 8b, 8c, and the claws 8a, 8b, 8c are clamped toward the central axis by a fastener (not shown), whereby the lens The holding member 4 is fixed. Further, since the mounting portion 44 is formed with the tapered portion 44a, there is a certain allowable range with respect to the degree of insertion of the mounting portion 44 and the degree of tightening of the claws 8a, 8b, 8c. .

FIG. 7 is a perspective view showing the shape of the seal 5. The seal 5 is generally made of soft rubber and is formed into a substantially disc shape having a diameter of about 35 mm. Further, a hole 5a having a diameter substantially the same as the inner diameter of the lens holding member 4 is formed in the central portion.

FIG. 8 is a sectional view taken along the line BB of FIG. The seal 5 comprises a central fibrous layer 51 and adhesive layers 52 and 53 on both sides thereof. The fibrous layer 51 is made of a soft rubber containing a fibrous material. The thickness of the entire seal 5 is set to 0.8 to 1.0 mm. This value is provided with an adequate margin so that the lens 1 is not damaged by the biting teeth 42 when the lens holding member 4 is pressed. The appropriate thickness of the entire seal 5 is changed depending on conditions such as the material of the lens holding member 4 and the shape of the biting teeth 42. Usually, it is preferable to set it to 0.2 to 3.0 mm.

FIG. 9 is an enlarged view of a part of the fibrous layer 51 of the seal 5. The fibrous layer 51 contains a large number of fibrous materials 512 assembled in a soft rubber 511 in a lattice pattern. As a result, the durability is maintained against the biting of the biting teeth 42, the twisting force received during the edging process, and the like, so that the lens 1 is prevented from being damaged and the clamp shaft 2 from being displaced.

Returning to FIG. 2, the operation of the main part of the eyeglass lens edging machine will be described. In order to perform the edging process on the lens 1, first, the adhesive layer 53 side of the seal 5 is attached to a predetermined portion of the front surface 1a of the lens 1. Then, the lens holding member 4 is fixed to the chuck 8 at the tip of the clamp shaft 2 while checking the position of the notch 45, and the seal 5 is pressed against the seal contact surface 41. At this time, since the adhesive layer 52 is formed on the surface of the seal 5 on the seal contact surface 41 side, the positioning work of the lens 1 is facilitated. When the lens 1 is positioned, the tip portion 3a of the clamp shaft 3 is pressed against the back side surface 1b of the lens 1. As a result, the lens 1 is fixed.

After the lens 1 is fixed, the clamp shafts 2 and 3 are rotated at the same rotation speed in the directions X 1 and Y 2, and the shaft 7 of the grindstone 6 is rotated in the direction Z 2. Then, by moving the clamp shafts 2 and 3 to bring the edge surface 1c of the lens 1 into contact with the grinding surface 6a of the grindstone 6, grinding is started.

FIG. 1 is a view showing a concrete coupling state between the lens holding member 4 and the seal 5. When the lens 1 is fixed by the clamp shafts 2 and 3, the biting teeth 42 of the lens holding member 4 bite into the seal 5 due to the pressing force. During the grinding process, a force that causes the lens holding member 4 to rotate the lens 1 and a torque that the lens 1 receives from the grindstone 6 act as a resistance force that causes a deviation between the lens holding member 4 and the seal 5. .

However, since the surface 42a on the rotation direction side of the biting tooth 42 is formed substantially perpendicular to the rotation direction, the resistance force can be received most efficiently. Therefore, it is possible to surely prevent the axial deviation of the lens 1.

Further, since the seal 5 that receives the force of the biting teeth 42 has the configuration in which the grid-like fibrous material 512 is contained in the soft rubber 511 as described above, the pressing force and the twisting force of the biting teeth 42 are Can withstand enough.

Further, since the radius of curvature of the seal contact surface 41 of the lens holding member 4 is formed to be smaller than that of the front side surface 1a of the lens 1, the edge portions 41a and 41b of the seal contact surface 41 are formed. Etc. bite into the seal 5 more strongly than other parts. Therefore, the torque applied from the lens holding member 4 to the seal 5 can be maximized, so that the lens 1 can be held more strongly.

As described above, the lens 1 can be fixed easily and surely only by attaching the lens holding member 4 and the seal 5 between the clamp shaft 2 and the lens 1.

[0030]

[Effect of device]

 As described above, in the present invention, the contact surface of the lens holding member with the elastic seal is formed with a plurality of teeth that bite into the elastic seal when rotated in a specific rotation direction. Even if a torque is applied to the teeth, the teeth bite into the elastic seal reliably, thereby preventing the elastic seal and the lens holding member from being displaced.

Further, since it is only necessary to attach the lens holding member and the elastic seal between the clamp shaft and the spectacle lens, the work is easy.

[Brief description of drawings]

FIG. 1 is a diagram showing a specific coupling state between a lens holding member and a seal.

FIG. 2 is a diagram showing a configuration of a main part of an eyeglass lens edging machine.

FIG. 3 is a perspective view showing a configuration of a lens holding member.

FIG. 4 is a diagram showing a specific shape of a biting tooth.

5 is a cross-sectional view taken along the line AA of FIG.

FIG. 6 is a diagram showing a method of connecting the lens holding member to the clamp shaft.

FIG. 7 is a perspective view showing the shape of a seal.

8 is a cross-sectional view taken along the line BB of FIG.

FIG. 9 is an enlarged view of a portion of the fibrous layer of the seal.

[Explanation of symbols]

 1 Lens 2,3 Clamp Shaft 4 Lens Holding Member 5 Seal 6 Grindstone 41 Seal Contact Surface 42 Biting Teeth

Claims (3)

[Scope of utility model registration request] 1. A spectacle lens holding device for holding a spectacle lens during edging of a spectacle lens, comprising: a clamp shaft that clamps the spectacle lens from both front and back directions and rotates in a specific rotation direction; An elastic seal attached to at least one of the front surface and the back surface of the spectacle lens, and a lens holding member that is attached to the tip of the clamp shaft on the elastic seal side and holds the spectacle lens while pressing the elastic seal, And having a contact surface with the elastic seal of the lens holding member,
A plurality of teeth that bit into the elastic seal when rotated in the specific rotation direction are formed. 2. The eyeglass lens holding device according to claim 1, wherein the elastic seal contains a fiber material having a lattice-like fibrous structure. 3. The contact surface of the lens holding member with the elastic seal is formed to have a predetermined radius of curvature, and the predetermined radius of curvature is formed to be smaller than the radius of curvature of the spectacle lens. The spectacle lens holding device according to claim 1, wherein the spectacle lens holding device is provided.