US990524A - Apparatus for grinding toric lenses. - Google Patents

Description

S.`D. GHALMERS L H. s. RYLAND.

- APPARATUS FOR GRINDING TOEIC LENSES. APPLICATION FILED JUNE 4, 1906. RENEWED SEPT. 22, 1910.

990524. Patented Apr. 25', 1911.

STEPHEN DRUMMOND CHLMERS AND HERBERT SIDNEY RYLAND, OF LONDON,

ENGLAND.V

APPARATUS FOR GRINDING TORI() LENSES.

9th-5.2%.' Specification of Application filed June 4. 1906. SerialNo. 320,110.

To all 'Lo/rom it may concern:

Be it known thaty we, STEPHEN DuennoND Cimmiunsand lli-:uumlr SIDNEY RY- Lxxn, both subjects of the King of Great Britain, residing at Northampton Institute, (lerkenwell, London, l'lngland, have invented certain neikand useful Apparatus for Grinding Toric Lenses. of whilthe follow.- ing is a specification.

Our invention relates to a new or improved apparatus for manufacturing lenses which have a surface of double curvature and are known as toric lenses.

According to our invention. the lenses to he ground and polished. having been prepared, are cemented symmetrically about the axis of revolution or oscillation of a suitable bed, table, or other support in such a manner that one of the desired curves is produced by such rotation or oscillation. The other curve is produced by the motion of a radius arm or bracket which iscentered on the desired axis and is held in the plane through the axis of revolution of the shaft.v The actual polishing tool is carried by said radius arm or bracket so as to rotate.

In the accompanying drawings, one form of the apparatus is shown, itv being understood that any suitable frame-Work and gearing (whether manual or power) may be emploved and the construction varied to suit circumstances.

Figure l is 'a front view and Fig. Q is an end view partly in section.

Asbefore stated, the lenses rz are cemented symmetrically about the axis of revolution or oscillation of a bed or table which in the example given comprises a disk 7 der...A

tachably fixed upon a suitable mandi-e or shaft c. It will thus be seen that. one of the desired curves will be that. which is dcscribed from the axis f1', so that the diameter of the disk chosen should be that which would best suit the desired curve of the lenses. For producing the other curve, a rotary grinding and (or) polishing tool d is oscillating more. or less in the direction of the axis fr, the center 7/ of'oscillation being adjusted to give the desired curve. As shown, the tool l is mounted i'i bearings upon a bracket or-radius arm e which may be reciprocated to a limited extent about the axis y, so that the speed of the tool is slightly greater or less than the peripheral speed of the work; for this pur-pose the arpi e may Letters Patent. Patented Apr. 25, 1911.

Renewed september 22, 1910. serial No. 583,283.

,conveniently derive its-motion from some moving part of the mechanism. rfhe .means for rotating the tool (Z, such as the endless cord or band f, must allow of the oscillating motion of the arm c. Any suitaole means may beemployed for feeding the vtool to and from its work.

The`periphery of the disk (or other bed or supportfor the lenses) is preferably formed approximately tothe curves which will be produced by the combined motions of the disk shaft c and the arm or bracket e, the lenses being cemented to said curved surface. "he working face of the grinding or polishing tool (l is preferably spherical, of radius equal to the longer radius of the Surface to be formed. the abrasive or polishing materials being supplied in the usual manner.

tures is concave, the working face of the grinding or polishing tool is turned to the desired curve or the steeper of the two concave curves. Necessarily for concave work the lenses Would be mounted upon the internal periphery of the drum, ring. or cup bed, while the axis y of the oscillating arm e would he located nearer to the work than the axis ai.

Prior t0 cementing the lenses to the bed, they may be shanked to shapeand roughed in cylindrical tools of approximately the required curvatures.

By adjusting the axis y/ of the arm c horizontally (such as by sliding the support g I in a horizontal direction more or less as required) lenses may be produced in which one of the curvatures continually increases from end to end.'

le elain.

1. An apparatus for manufacturing toric lenses comprising a rotatable support adapted to carry a single row of lenses upon its periphery, a rotatable tool arranged in operative relation to said support and havingr its axis disposed at right. angles to that of said tool arranged for movement at. right rotatable support.

2. An apparatus for manufacturing torio lenses comprising a rotatable support adapted to carry a single row of synnnetrieallyarranged lenses upon its periphery, a rotatable grinding tool arranged in operative .ln the case where one or both of the curva-A the latter, and an oscillatory support forA angles to the direction of motionk of thc 'the radius of which s different from that of ltatable support,

In' testimony whereof we have hereunto Set our hands in presence of two subscrbl@ ing witnesses.

STEPHEN DRUMMOND CHALMERS. HERBERT SIDNEY RYLAN'D. /Vtnesses GEORGE C. DOWNING, WALTER I. SKERTEN.

'relation to said subport" and ha Vingt; its axis (hsposwd at right angles to that oi the latter, said tool having a curved grmdmg face` said support, au@ an oscillatory support for -saixttool arranged for movement at right angles to the dlrcetion of motlon of the ro- Copies of this patent may be obtained for ive cents each, by adressing the Commissioner 4of Patents.

Washington, D. C.

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