Optical-grade surfacing tool

Patent metadata

Field	Value
Publication number	US-11969848-B2
Application number	US-201716467867-A
Country	US
Kind code	B2
Filing date	Oct 27, 2017
Priority date	Dec 9, 2016
Publication date	Apr 30, 2024
Grant date	Apr 30, 2024

Abstract

The tool includes a base including a rigid carrier and a flexible collar encircling the rigid carrier; an elastically compressible interface; and a flexible buffer including a central portion that is located in line with the rigid carrier and a peripheral portion that is located transversely therebeyond. This peripheral portion is connected to the carrier exclusively via the interface and via the collar, wherein the collar is configured so that the tool is elastically deformable between a rest position that it adopts in the absence of stress and a reference position in which the transverse end second surface of the flexible buffer is pressed against a reference surface that is spherical and of radius included between 40 mm and 1500 mm.

First claim

The invention claimed is:

1. An optical-grade surfacing tool ( 10 ), comprising:
a base ( 11 ) comprising a rigid holder ( 12 ) and a flexible collar ( 13 ) encircling said rigid holder ( 12 ), said rigid holder ( 12 ) having a transverse end surface ( 14 ), and said collar ( 13 ) having a transverse end surface ( 15 ) that is located on a same side as the transverse end surface ( 14 ) of the rigid holder ( 12 );
an elastically compressible interface ( 16 ) comprising a first transverse end surface ( 17 ), a second transverse end surface ( 18 ), and a lateral surface ( 19 ) extending from a periphery of the first transverse end surface ( 17 ) to a periphery of the second transverse end surface ( 18 ), the first transverse end surface ( 17 ) of the elastically compressible interface ( 16 ) being attached to the transverse end surface ( 14 ) of the rigid holder ( 12 ) and to the transverse end surface ( 15 ) of the collar ( 13 ); and
a flexible buffer ( 20 ) having a third transverse end surface ( 21 ) that is attached to the second transverse end surface ( 18 ) of the elastically compressible interface ( 16 ) and a fourth transverse end surface ( 22 ) that is configured to be applied against a surface ( 23 ) to be worked, said buffer ( 20 ) comprising a central portion ( 24 ) that is located plumb with the transverse end surface ( 14 ) of the rigid holder ( 12 ) and a peripheral portion ( 25 ) that is located transversely beyond the transverse end surface ( 14 ),
said peripheral portion ( 25 ) being joined to the holder ( 12 ) exclusively by said interface ( 16 ) and by said collar ( 13 ), and
said collar ( 13 ) being elastically deformable configured so that the tool ( 10 ) elastically deforms between a rest position in which the tool is free of any force applied for pressing the flexible buffer ( 22 ), and a reference position in which the second transverse end surface ( 22 ) of the flexible buffer ( 20 ) is pressed against a reference surface ( 37 , 40 , 46 , 47 ) that is spherical with a radius ranging from 40 mm and 1500 mm,
wherein the collar ( 13 ) is subdivided into petals, each of the petals ( 27 ) extending from the rigid holder to a far end, and
wherein each of the petals ( 27 ) has an axial thickness that varies as a function of a distance x from the holder to the far end of the petal, and wherein the thickness for each said petal is the same at any given distance x.

2. The tool as claimed in claim 1 , wherein:
for a surface to be worked that is concave, the tool is configured to assume a first concave reference position in which the second transverse end surface ( 22 ) of the flexible buffer is pressed against a first concave reference surface ( 37 ) that is spherical, concave and of radius of 1500 mm, and also a second concave reference position in which the second transverse end surface ( 22 ) of the flexible buffer is pressed against a second concave reference surface ( 40 ) that is spherical, concave and of radius of 40 mm; and
for a surface to be worked that is convex, the tool is configured to assume a first convex reference position in which the second transverse end surface ( 22 ) of the flexible buffer is pressed against a first convex reference surface ( 46 ) that is spherical, convex and of radius of 40 mm, and also a second convex reference position in which the second transverse end surface ( 22 ) of the flexible buffer is pressed against a second convex reference surface ( 47 ) that is spherical, convex and of radius of 1500 mm.

3. The tool as claimed in claim 1 , wherein the tool has an elastic stiffness, furnished by the interface ( 16 ) and the collar ( 13 ), such that the tool ( 10 ) transitions from the rest position to the reference position when a force comprised between 30 N and 180 N is applied to the holder ( 12 ) coaxially to the tool ( 10 ) while the tool ( 10 ) is coaxial with the reference surface ( 40 , 47 ).

4. The tool as claimed in claim 1 , wherein said collar ( 13 ) has an elastic stiffness such that the tool ( 10 ) transitions from the rest position to the reference position when a force is applied to the holder ( 12 ) coaxially to the tool while the tool ( 10 ) is coaxial with the reference surface ( 40 , 47 ) causing the holder ( 12 ) to travel a distance from the rest position to the reference position, where the holder ( 12 ) travels the distance at a set movement speed of 25 mm/s, and a ratio of a value of the force and a value of the distance traveled by the holder ( 12 ) from the rest position to the reference position is between 3 N/mm and 15 N/mm.

5. The tool as claimed in claim 4 , wherein said ratio is comprised between 5 N/mm and 8 N/mm.

6. The tool as claimed in claim 1 , wherein the transverse end surface ( 15 ) of the collar ( 13 ) is flush with the transverse end surface ( 14 ) of the holder ( 12 ).

7. The tool as claimed in claim 1 , wherein said petals ( 27 ) are subdivided by radially oriented slits ( 26 ).

8. The tool as claimed in claim 1 , wherein a combined total surface area of the petals ( 27 ) is between 30 and 80% of an annular area extending from the rigid holder ( 12 ) with an inner radius defined by an innermost extent of the cavities to an outer radius defined by the outermost extent of the petals.

9. An assembly comprising a polishing machine ( 29 ) and a tool as claimed in claim 1 ,
wherein said machine ( 29 ) is configured to apply, to the holder ( 12 ) of the tool ( 10 ), a preset machine force ( 31 ) of constant value, and
wherein a stiffness of said tool ( 10 ) is configured so that the tool transitions from the rest position to the reference position when between 85% and 100% of said constant value of the machine force ( 31 ) is applied to the holder ( 12 ) coaxially to the tool ( 10 ) while the tool is coaxial with the reference surface ( 40 ).

10. The tool as claimed in claim 2 , wherein the tool has an elastic stiffness, furnished by the interface ( 16 ) and the collar ( 13 ), such that the tool ( 10 ) transitions from the rest position to the reference position when a force comprised between 30 N and 180 N is applied to the holder ( 12 ) coaxially to the tool ( 10 ) while the tool ( 10 ) is coaxial with the reference surface ( 40 , 47 ).

11. The tool as claimed in claim 2 , wherein said collar ( 13 ) has an elastic stiffness such that the tool ( 10 ) transitions from the rest position to the reference position when a force is applied to the holder ( 12 ) coaxially to the tool while the tool ( 10 ) is coaxial with the reference surface ( 40 , 47 ) causing the holder ( 12 ) to travel a distance from the rest position to the reference position, where the holder ( 12 ) travels the distance at a set movement speed of 25 mm/s, and a ratio of a value of the force and a value of the distance traveled by the holder ( 12 ) from the rest position to the reference position is between 3 N/mm and 15 N/mm.

12. The tool as claimed in claim 3 , wherein said collar ( 13 ) has an elastic stiffness such that the tool ( 10 ) transitions from the rest position to the reference position when a force is applied to the holder ( 12 ) coaxially to the tool while the tool ( 10 ) is coaxial with the reference surface ( 40 , 47 ) causing the holder ( 12 ) to travel a distance from the rest position to the reference position, where the holder ( 12 ) travels the distance at a set movement speed of 25 mm/s, and a ratio of a value of the force and a value of the distance traveled by the holder ( 12 ) from the rest position to the reference position is between 3 N/mm and 15 N/mm.

13. The tool as claimed in claim 2 , wherein the transverse end surface ( 15 ) of the collar ( 13 ) is flush with the transv

Assignees

• Essilor Int

Inventors

• Gacoin Eric
• Kress Pierre
• Stephane Jean
• Saulny Jonathan

Classifications

• B24B13/012 Primary

  conformable in shape to the optical surface, e.g. by fluid pressure acting on an elastic membrane · CPC title

• B24B7/24

  for grinding or polishing glass · CPC title

• B24D13/142

  Wheels of special form · CPC title