JPH09225798A - Lens pressing member - Google Patents

Abstract

PROBLEM TO BE SOLVED: To more correctly hold a lens in a lens pressing member which is fitted to a tip of a holding shaft to hold a lens and is brought into pressure contact with the lens surface. SOLUTION: An elastic member 273 is fitted in a clearance of a connection part between a pressure contact head part 272 and a base part 271. Even when the self-weight or a temporary force from the outside is applied to the pressure contact head part 272, the direction of a pressure contact surface 272a is kept in an approximately perpendicular direction to the axis of a holding shaft due to the effect of the elastic force in the thickness direction of the elastic member 273. When the holding shaft is moved to a side of an eyeglass lens fixed to the holding shaft, the elastic member 273 is deformed and the direction of the pressure contact head part 272 is changed according to the shape of the lens surface.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lens pressing member that is attached to the tip of a holding shaft that holds a lens and is in pressure contact with a lens surface, and more particularly to a lens pressing member having a universal joint.

[0002]

2. Description of the Related Art Conventionally, it has been necessary to securely hold a lens in an eyeglass lens edging device, a lens shape measuring device and the like. For example, in a edging device, a spectacle lens to be processed is held by a lens holding unit and brought into contact with a grindstone. The lens holding unit is provided with two holding shafts, and these holding shafts hold the spectacle lens.

This clamping position is not always the optical center position of the lens, but it may be eccentrically clamped, and the lens surface also has a different curvature and shape depending on the prescription and the power of the lens. FIG. 6 is a diagram showing a configuration example of a conventional lens holding mechanism section in a lens holding unit. Holding shaft 61 and holding shaft 6
2 are provided so as to rotate in synchronization with each other.
A holder receiver 63 is attached to the tip of the holding shaft 61. A holder 65 to which a spectacle lens 64 is fixed is attached to the holder receiver 63. The spectacle lens 64 is
It is fixed to the holder 65 on the side of the convex surface 64a.

A pressing member 66 is attached to the tip of the other holding shaft 62. The pressing member 66 is mainly composed of a base portion 661 and a pressure prefix portion 662. The pressure prefix 662 is connected to the base 661 via a universal joint (not shown).
As a result, the pressure prefix portion 662 can freely change the direction of the pressure contact surface 662a within a predetermined range.

The holding shaft 62, to which such a pressing member 66 is attached, moves toward the spectacle lens 64 and presses the pressure prefix portion 662 against the concave surface 64b. At this time, in the pressure prefix portion 662, the pressure contact surface 662a faces the most balanced direction according to the shape of the concave surface 64b. Therefore, the pressure prefix 662 always has the concave surface 64b over the entire pressure contact surface 662a.
Can be pressed with even force.

[0006]

However, since the conventional pressing member 66 does not have a mechanism for holding the pressure prefix portion 662 in a fixed direction, when it receives its own weight or a force from the outside, the pressure member 662 shown in FIG. ), The pressure prefix 662 remains tilted. Pressure prefix 662 in this tilted state
Is moved to the concave surface 64b side, as shown in FIG. 6B, the pressure contact surface 66 is largely displaced from the direction of the concave surface 64b.
2a will be in pressure contact.

However, also at this time, the pressure prefix 662 naturally changes its direction while slipping on the concave surface 64b in conformity with the shape of the concave surface 64b, and finally presses the concave surface 64b over the entire pressure contact surface 662a. However, in this case, since the amount of slippage is large, there is a risk that the position and shape of the spectacle lens 64 may change significantly due to friction.

The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide a lens pressing member that can reduce the amount of slip when the lens surface is pressed and can hold the lens accurately. To aim.

[0009]

According to the present invention, in order to solve the above problems, a holding member for a lens, which is attached to the tip of a holding shaft for holding a lens and presses against a lens surface, is directly connected to the holding shaft. A base part that is connected to the base part via a universal joint, and is attached to a pressure prefix part that is in pressure contact with the lens surface, and a gap between a connection part between the pressure prefix part and the base part, A pressing member for a lens is provided, which comprises: an elastic member that resists the weight of the pressure prefix and has an elastic force that is weaker than the pressure contact force of the pressure prefix with the lens surface.

In such a lens pressing member, since the pressure prefix is connected to the base through the universal joint, the direction can basically be freely changed within a predetermined angle range. However, due to the elastic force of the elastic member mounted in the gap between the pressure prefix and the base, the pressure prefix can withstand its own weight and normally tilts with respect to the axis of the holding shaft. Has been thwarted. Therefore, during the holding operation of the lens, the pressure prefix can be always brought into contact with the lens surface in the direction along the axis.

On the other hand, when the pressure prefix is brought into pressure contact with the lens surface, the elastic member is deformed according to the pressure contact force, so that the direction of the pressure prefix changes according to the shape of the lens surface. At this time, the pressure prefix changes direction while slipping on the lens surface, but it always changes with reference to the direction along the axis, so the slip amount is average regardless of the direction of the lens surface. , Will never be extremely high.
Therefore, changing or deforming the position of the spectacle lens at the time of slippage is reduced as much as possible, and the lens can be held more accurately.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings. FIG. 2 is a perspective view showing the outer appearance of a edging device for an eyeglass lens in which the pressing member of this embodiment is used. The edging device 10 has the entire function housed in a main body case 11 and a soundproof cover 12. A power switch 111 and an operation panel 11 are provided on the front side of the body case 11.
2, a size dial 113 and the like are provided. on the other hand,
A lens holding unit 13 is provided inside the main body case 11. The lens holding unit 13 includes a slide shaft 131 provided on the upper rear side of the main body case 11.
In addition, it is attached so as to be slidable from side to side as viewed from the front of the apparatus and rotatable.

A concave portion 132 is formed on the front surface side of the lens holding unit 13. The lens holding mechanism portion 14 is provided in the recess 132. The lens holding mechanism unit 14 clamps and holds the spectacle lens by tightening the chucking grip 141, and controls the rotation of the held spectacle lens. The lens holding mechanism section 14 is protected by a waterproof cover 133 provided in the lens holding unit 13.

A lens template holding mechanism portion 15 is provided on the left side of the lens holding unit 13. A lens template 15a having a target processing shape is attached to the lens template holding mechanism section 15. Inside the main body case 11, the lens template 15 a is provided below the lens template holding mechanism section 15.
Is provided with a lens template contact member 16.
The lens template contact member 16 is supported by an arm 17. The arm 17 is attached to a part of the lens holding unit 13, is vertically rotatable, and is slidable integrally with the lens holding unit 13.

A polishing section 18 is provided inside the main body case 11 and below the lens holding mechanism section 14. The polishing section 18 is provided with a rotary grindstone, and the spectacle lens is processed by this grindstone.

FIG. 3 is a front view showing the structure of the lens holding mechanism portion 14. The lens holding mechanism portion 14 is provided with two holding shafts 21 and 22. The holding shaft 21 and the holding shaft 22 are provided so as to rotate in synchronization with each other. A holder receiver 23 is integrally attached to the tip of the holding shaft 21. A holder 25 to which a spectacle lens 24 is fixed is attached to the holder receiver 23. The spectacle lens 24 is fixed to the holder 25 via a pad 26 attached to the convex surface 24a side.

At the tip 22a of the other holding shaft 22,
The pressing member 27 is attached. The holding shaft 22 is
Move to the side of the spectacle lens 24 and move the pressing member 27 to the concave surface 2
Press contact with 4b. As a result, the spectacle lens 24 is held.

4A and 4B are views showing the external structure of the pressing member 27. FIG. 4A is a view as seen from a direction perpendicular to the axis, and FIG.
Is a view from the pressure prefix side. The pressing member 27 mainly includes a base portion 271 and a pressure prefix portion 272. The pressure prefix portion 272 is connected to the base portion 271 via a universal joint described later.

A ring-shaped contact member 272 made of synthetic rubber is formed at the edge of the pressure contact surface 272a of the pressure prefix portion 272.
b is attached. The contact member 272b directly contacts the concave surface 24b of the spectacle lens 24.

An elastic member 273 is mounted in the gap between the connecting portion between the pressure prefix portion 272 and the base portion 271.
5A and 5B are views showing the shape of the elastic member 273. FIG. 5A is a plan view and FIG. 5B is a side view. The elastic member 273 is formed in a ring shape as a whole, and the outer shape thereof is the pressure prefix 272.
It is formed to the same extent as, and is formed to a thickness of about several millimeters. The elastic member 273 is formed of, for example, sponge. Further, the elastic member 273 has an inner diameter such that the base portion 271 or the pressure prefix portion 272 can be easily inserted into the inner portion 273a when the elastic member 273 is pulled outward and expanded.

FIG. 1 is a view showing the internal structure of the pressing member 27 with the elastic member 273 attached, and FIG.
It is sectional drawing cut | disconnected along XX of FIG. Base 27
A hole 271a is formed in the inside of the device 1. This hole 27
The tip portion 22a of the holding shaft 22 is inserted into the la 1a. Further, the base portion 271 is formed with a screw hole 271b penetrating the hole 271a from the side surface. This screw hole 271b
A screw (not shown) is screwed into the shaft, so that the base 271 is fixed to the holding shaft 22.

A mounting piece 27 is attached to the tip of the base 271.
1c is formed. In this attachment piece 271c,
Through the universal joint 30, the pressure prefix 272
Are connected. This universal joint 30
Is mainly composed of the shaft 31, the intermediate ring 32, and the shafts 33 and 34. The intermediate ring 32 is rotatably attached to the attachment piece 271c by the shaft 31. The pressure prefix 27 is applied to the intermediate ring 32.
2 is rotatably attached by shafts 33 and 34 that are perpendicular to the shaft 31. As a result, the pressure prefix 272 becomes
It is possible to face the base portion 271 in any direction within a predetermined angle range.

An elastic member 273 is mounted in the gap between the connecting portion between the pressure prefix portion 272 and the base portion 271. The elastic member 273 is pulled outward and the ring is spread,
It is mounted by fitting it from the base portion 271 side or the pressure prefix portion 272 side.

In the pressing member 27 having such a structure, when only the weight of the pressure prefix portion 272 is applied, the pressure prefix portion 272 tends to move downward. However, the elastic member 2
By the action of the elastic force in the thickness direction of 73, the pressure prefix 272
Of the pressure contact surface 272a is maintained in a direction substantially perpendicular to the axis of the holding shaft 22 (hereinafter, referred to as a steady state).
Further, even when a force is temporarily applied from the outside, if it is released from it, the original steady state is immediately restored.

Then, when the holding shaft 22 moves to the side of the spectacle lens 24 fixed to the holding shaft 21, and the pressure prefix 272 comes into pressure contact with the concave surface 24b as shown in FIG. 3,
The elastic member 273 is deformed by the pressure contact force. As a result, the direction of the pressure prefix 272 changes according to the shape of the concave surface 24b.

At this time, the pressure prefix 272 changes its direction while slipping on the concave surface 24b, but since it always changes with respect to the axial center of the holding shaft 22 based on the direction, it does not matter which direction the concave surface 24b is slipping. The amount is average, never extremely high. Therefore, changing or deforming the position of the spectacle lens 24 at the time of slippage can be reduced as much as possible, and the lens can be held more accurately.

When the holding shaft 22 is separated from the spectacle lens 24 again after the processing of the spectacle lens 24 is completed, the pressure prefix 27
2 immediately returns to its original steady state. As described above, in this embodiment, the base portion 27 connected by the universal joint is used.
Since the elastic member 273, which is an elastic member, is mounted in the gap between the connecting portions of 1 and the pressure prefix portion 272, the steady state can be maintained even if the self-weight or external force is applied. Therefore, the pressure prefix 272 is always attached to the spectacle lens 24 in a fixed direction.
Can be pressed against. On the other hand, when the pressure prefix 272 is pressed against the spectacle lens 24, the concave surface 2
Since the orientation changes according to the shape of 4b, the spectacle lens 2
4 can be held accurately.

Further, in this embodiment, since the sponge is used as the elastic member 273, the cost is low and the manufacturing is simple. In this embodiment, the lens holding mechanism portion 14 of the edging device 10 is used as a lens pressing member.
However, the invention can also be applied to a lens holding mechanism portion of a lens shape measuring device or the like.

[0029]

As described above, according to the present invention, the base portion and the pressure prefix portion are connected through the universal joint, and the elastic member is mounted in the gap between the pressure prefix portion and the base portion. Since the pressure prefix can withstand its own weight and can usually be prevented from tilting with respect to the axis of the holding shaft, the pressure prefix is always oriented along the axis. Can be contacted with. On the other hand, when the pressure prefix is brought into pressure contact with the lens surface, the elastic member is deformed according to the pressure contact force, so that the direction of the pressure prefix can be easily changed according to the shape of the lens surface. At this time, the pressure prefix slips on the lens surface, but since it always changes with reference to the direction along the axis, the slip amount is average regardless of the direction of the lens surface, and extremely. It won't increase.

Therefore, it is possible to minimize changing or deforming the position of the spectacle lens at the time of slip, and it is possible to hold the lens more accurately.

[Brief description of drawings]

FIG. 1 is a view showing an internal configuration of a pressing member with an elastic member attached, and is a cross-sectional view taken along line XX of FIG. 4 (B).

FIG. 2 is a perspective view showing an outer appearance of a edging device for an eyeglass lens in which the pressing member of the present embodiment is used.

FIG. 3 is a front view showing a configuration of a lens holding mechanism section.

FIG. 4 is a diagram showing an external configuration of a pressing member, FIG.
Is a view seen from a direction perpendicular to the axis, and (B) is a view seen from the pressure prefix side.

5A and 5B are diagrams showing a shape of an elastic member, FIG. 5A being a plan view and FIG. 5B being a side view.

FIG. 6 is a diagram showing a configuration example of a conventional lens holding mechanism portion in a lens holding unit.

FIG. 7 is a view showing a structure of a conventional pressing member,
(A) is a figure which shows the state which the pressure prefix part inclines, and (B) is a figure which shows the state which the inclined pressure prefix part contacts a spectacle lens.

[Explanation of symbols]

 10 Edge edging device 13 Lens holding unit 14 Lens holding mechanism part 21,22 Holding shaft 23 Holder receiving 24 Eyeglass lens 24a Convex surface 24b Concave surface 25 Holder 30 Universal joint 27 Holding member 271 Base part 272 Pressure prefix 273 Elastic member

Claims (2)

[Claims] 1. A holding member for a lens, which is attached to a tip of a holding shaft for holding a lens and is in pressure contact with a lens surface, a base part directly connected to the holding shaft, and the base part via a universal joint. A pressure prefix that is connected to the lens surface and is pressed against the lens surface, and is mounted in a gap between the pressure prefix and the base portion, and resists the self-weight of the pressure prefix and that of the pressure prefix. An elastic member having an elastic force weaker than the pressure contact force to the lens surface, and a lens pressing member. 2. The lens pressing member according to claim 1, wherein the elastic member is formed of sponge.