Device for fine processing of optically effective surfaces on, in particular, eyeglass lenses

Patent metadata

Field	Value
Publication number	US-10583540-B2
Application number	US-201515519643-A
Country	US
Kind code	B2
Filing date	Sep 17, 2015
Priority date	Oct 15, 2014
Publication date	Mar 10, 2020
Grant date	Mar 10, 2020

Abstract

A device for fine processing of optically effective surfaces on workpieces has a workpiece spindle which protrudes into a working space and by which a workpiece to be polished can be rotationally driven about a workpiece axis of rotation. Two tool spindles are associated with the workpiece spindle and protrude into the working space oppositely to the workpiece spindle. On each tool spindle, a polishing tool can be rotationally driven about a tool axis of rotation and is retained so that the polishing tool can be axially advanced along the tool axis of rotation. Furthermore, the tool spindles can be moved together in relation to the workpiece spindle along a linear axis extending substantially perpendicularly to the workpiece axis of rotation and can be pivoted about different pivoting adjustment axes, which extend substantially perpendicularly to the workpiece axis of rotation and substantially perpendicularly to the linear axis.

First claim

The invention claimed is:

1. A device for fine processing of optically effective surfaces of, spectacle lenses as workpieces, comprising a workpiece spindle, which projects into a work space and by way of which a workpiece to be polished is drivable for rotation about a workpiece axis of rotation, and two tool spindles which are both associated with the workpiece spindle and project oppositely into the work space and on each of which a respective polishing tool is mounted to be drivable for rotation about a tool axis of rotation and to be axially adjustable along the tool axis of rotation, the tool spindles having their respective axis of rotation being movable in common relative to the workpiece spindle along a linear axis extending substantially perpendicularly to the workpiece axis of rotation and being pivotable about different pivot setting axes extending substantially perpendicularly to the workpiece axis of rotation and substantially perpendicularly to the linear axis, wherein the tool spindles are arranged one behind the other as seen in a direction of the linear axis and are movable along the linear axis such that either tool spindle can be positioned to operate with the workpiece spindle.

2. A device according to claim 1 , wherein the pivot setting axes lie in a notional plane extending along the linear axis or parallel thereto.

3. A device according to claim 1 , wherein one tool spindle is mounted on a front pivot yoke, which is pivotably connected with a tool carriage to be capable of defined pivotation about one pivot setting axis, whereas the other tool spindle is mounted on a rear pivot yoke, which is pivotably mounted on the tool carriage to be capable of defined pivotation about the other pivot setting axis, the carriage in turn being guided with respect to a frame, which surrounds the work space, to be drivable along the linear axis.

4. A device according to claim 3 , wherein provided for movement and positioning of the tool carriage, which is guided on two guide rods connected with the frame, is a rotary drive which is stationary with respect to the frame and disposed in drive connection with a ball screw drive having a rotatably mounted ball screw spindle which engages a nut connected with the tool carriage to be secure against relative rotation.

5. A device according to claim 3 , wherein provided for defined pivotation of the two tool spindles about the pivot setting axes is a linear drive which is pivotably connected by one end thereof with one pivot yoke at a spacing from the corresponding pivot setting axis and by the other end thereof with the tool carriage, and wherein the one pivot yoke is drivingly connected with the other pivot yoke by way of a coupling rod which, at a spacing from the pivot setting axes, is pivotably connected by one end thereof with the one pivot yoke and by the other end thereof with the other pivot yoke.

6. A device according to claim 1 , wherein each tool spindle has for axial adjustment of the respective polishing tool along the associated tool axis of rotation a piston-cylinder arrangement with a piston, which is received in a cylinder housing and which is connected in coaxial arrangement with a spindle shaft to be effective for actuation, the spindle shaft together with the piston-cylinder arrangement being mounted in a spindle housing to be rotatable about the respective tool axis of rotation.

7. A device according to claim 6 , wherein the piston-cylinder arrangement is pneumatically actuable, and wherein the cylinder housing of the pneumatically actuable piston-cylinder arrangement is of two-part construction and lined by a guide sleeve of mineral glass in which the piston, which at its guide surface is made from a graphite material, is received to be longitudinally displaceable.

8. A device according to claim 6 , wherein the piston of the piston cylinder arrangement is rigidly connected with the spindle shaft by way of a thin rod of spring steel.

9. A device according to claim 6 , wherein the cylinder housing is provided at the outer circumference with a toothing for engagement of a cogged belt which is drivable by way of a motor, which is flange-mounted on the respective pivot yoke, with a belt pulley so as to rotate the piston-cylinder arrangement and thus the spindle shaft about the respective tool axis of rotation.

10. A device according to claim 6 , wherein provided for torque transmission from the cylinder housing of the piston-cylinder arrangement to the spindle shaft is a splined shaft guide with guide grooves formed in the spindle shaft and a flange nut which is engaged with the grooves by way of an axial bearing element and which is connected with the cylinder housing to be secure against relative rotation.

11. A device according to claim 6 , wherein the polishing tool comprises a tool mounting head which is securable to the respective spindle shaft to be capable of axial and rotational entrainment and on which a polishing disc is exchangeably mounted, for which purpose a base body of the polishing disc and the tool mounting head are provided with complementary structures for axial detenting and for rotational entrainment of the polishing disc by the tool mounting head.

12. A device according to claim 11 , wherein the tool mounting head has a ball joint with a ball head, which is received in a ball socket and which is formed on a ball pin securable to the spindle shaft of the respective tool spindle, the ball socket being formed in a mounting plate with which the polishing disc is detentable.

13. A device according to claim 12 , wherein the ball head has a receiving bore for a transverse pin which extends through the ball head and engages on either side of the ball head with associated recesses in the ball socket so as to connect the mounting plate with the ball pin to be capable of rotational entrainment.

14. A device according to claim 12 , wherein the mounting plate is so resiliently supported by way of a resilient annular element on a support flange at the ball pin side that the polishing disc detented with the mounting plate seeks to self-align by its center axis with the ball pin and thus the spindle shaft of the respective tool spindle.

15. A device according to claim 11 , wherein the tool mounting head in an axially retracted setting of the spindle shaft is detentable by means of a detent device with the cylinder housing or a part connected therewith to be secure against relative rotation.

16. A device according to claim 15 , wherein the detent device comprises a plurality of spring projections which are distributed over the circumference of the tool mounting head and project along the respective tool axis of rotation and which mechanically positively engage with lugs in an annular groove formed at the cylinder housing or the part connected therewith to be secure against relative rotation.

17. A device according to claim 1 , wherein a lower region of the work space into which the workpiece spindle projects is bounded by a trough which is integrally deep-drawn from a plastics material and has step-free wall surfaces.

18. A polishing machine for simultaneous polishing of at least two spectacle lenses, comprising a machine frame in which in correspondence with the number of spectacle lenses to be simultaneously polished at least two devices are arranged, each device having a workpiece spindle, which projects into a work space and by way of which a workpiece to be polished is drivable for rotation about a workpiece axis of rotation, and two tool spindles which are both associated with the workpiece spindle and proje

Assignees

• Satisloh Ag

Inventors

• Wallendorf Steffen
• Schäfer Holger
• Philipps Peter
• Kaufmann Andreas

Classifications

• B24B9/14

  of optical work, e.g. lenses, prisms {(control of the position of the tool for bevelling optical work B24B47/225)} · CPC title

• B24B13/0037 Primary

  the lenses being worked by different tools, e.g. for rough-grinding, fine-grinding, polishing · CPC title

• B24B13/005

  Blocking means, chucks or the like; Alignment devices · CPC title

• B24B27/0076

  grinding machines comprising two or more grinding tools · CPC title

• B24B13/00 Primary

  Machines or devices designed for grinding or polishing optical surfaces on lenses or surfaces of similar shape on other work; Accessories therefor (edging optical work, e.g. lenses, prisms B24B9/14) · CPC title