US912518A

US912518A - Lens-grinding machine.

Info

Publication number: US912518A
Application number: US41156208A
Authority: US
Inventors: Louis Wilhelm
Original assignee: GLOBE OPTICAL CO
Current assignee: GLOBE OPTICAL CO
Priority date: 1908-01-20
Filing date: 1908-01-20
Publication date: 1909-02-16
Anticipated expiration: 1926-02-16

Description

' Ll WILHELM.

LENS GRINDING MAGHINE. APPLIUATION FILED JANzo, 190s.

Patented Feb. 16, 1909.

IIT- E ,1f/1,111,111,141,

0V l W zen of the United States, residing .UNTTED STATES PATENT OFFTCE LOUlS WlLllllLM., O'r \\'ORCES1`1QR, h'liiSSACl-IUSETTS, ASSTGNO'R TO GLOBE OPTICAL CO., OF BOSTON, MASSAGE USllTTS, A CORPORATION OF MASSACHUSETTS.

LENS-GRINDIN MACHINE Specification of Letters Patent.

Patented Feb. 16, 1909.

Application filed January 20, 1998. Serial Nal/111,562.

To all whom it muy concern:

ie it known that l, LOUIS lVILiisnM, a citiat Worcester. in the county of lVorcc-ster and State of hilassachusetts. have invented a new and useful Lens-GrindinO Machine, of which the following is a specification.

This invention relates to a grinding niachine for shaping lenses for spectacles and eye-glasses, and for similar purposes.

The principal objects of the invention are vto provide a machine of this character with means whereby they shafts, and operating parts for supporting the work will be protected from the dirt, mud, etc., which is thrown about in the use of machines of this character; also to provide means whereby when the former is covered with inudtand dirt, and thus obscured, the position thereof will be apparent to the eye so that it will nothe necessary to clean it every time itis desired to4 inspect it; also to provide iinproved means for supporting the two worksupport'ing shafts; to provide an improved arrangeinent for regulating the position of the work withfrespect to the grinding stone; and to provide an additional tension device for causing the work to bear harder on the stone when the thick edges are being ground than when the thin ones are presented to the stone.

Further objects and advantages of the invention will appear hereinafter.

Reference is to be had to the accompanying drawings which show one embodiment of the invention, and in whichG Figure lis a plan thereof with parts in section. Fig. 2, is an elevation of aport-ion of one part of same. Fig. 3 is a transverse sectional view on the line 3- 3 of Fig. 1. Fig. 4t is an end elevation, and Fig. 5 is a plan of an enlarged' scale showing certain details of construction and illustrating how the work supported in the machine.

The invention is shown as comprising a.

base-plate 10 provided with bosses 11 havinghearings for a. shaft 1Q. This shaft is pi'ovided with a gear 13 through which the device is driven in any desired way. It is also provided with a pair of pinions 14 meshing with gears 1501i a pair of work-supporting .shafts 1G and 17 for driving the latter. The

shafts 1G and 17 are ,adapted to swing about the shaft 12.' being supported therefrom by .a frame which constitutes a casing for these three shafts and is shown as made up of a cylindrical portion 18 and two

cylindrical portions

19 and 20. The latter two cylindrical portions are connected with the cylindrical portion 18 by integral cross pieces or struts 2l. On account of having theshafts housed in this casing or frame the shafts .are protected from the accumulation of dirt and quently. The portion 18 is simply hollow to permit the shaft 12 to pass through it, y and it is provided with bearings at its ends whereby the whole frame can swing on this shaft.' The casing 20 is similarly constructed, one of the bearings Q2 being shown in Fig. 5. A ball retainer 220 is shown with a. cone 921 having` a curved 'conical surface of suoli a slant that when the shaft is pushed to the left by the other shaft` as it is when in operation, the bearing balls will he forced Aoutwardly, and will hohl the shaft firmly against vibration. At the end of the cone 221 are a pair of fcltwashers 222 to keep the bearing free from dust, etc. onwhich bears a plate fixed to a sleeve 224 which is lixed to the shaft 17 by a pin 225.

is removable and on the shaft 1G in this casing` is a ball hearing near the bearing or'col- .lar Q4. Near the other end is a felt washer 2522 held in place by a plate A spring is located inthe casing on the shaft 16 between the ball bearing and a pin 26 and tends to force the shaft 1G toward the shaft 17. ln order to provide for moving the shaft lo back in order to place the work a in the jaws 27 or remove it therefrom, the cas- -ing 19 is provided with lugs QS having bearings for a sliding` rod 2S), which is operated by a lever 30 and engages the gear 15. The operation of this lever will move the gear 15 hack, and this will move the shaft 16. vBoth 'of the gears l5 are protected from mud and dirt by means of guardll located at the ends of the

casings

19 and 20.

The tilting frame is provided with the usual tension device 3Q, and in addition thereto a separate adjustable tension device is provided for the purpose of varying the pressure of the work against the grinding stone one or more times duringa coni'plete revolution. This is desirable in grinding convex glasses, because in thatcase the edges being ground at two sides are thicker than The casing 19 is provided with bearings or collars 253 and 241- near its ends, one of which unid and do not have to he cleaned frethose at the other two sides. ln order to accomplish this, the shaft l? is provided with an attachment on its end which is connected to a tension device shown in the forni of a lever having notches 37 thereon connected with a chain 38 and spring 39 of any desired form. The attachment is preferably elliptical in form, and is fixed to the end of the shaft by a screw 40 usually' in a position with its axis at right angles to the long axis of the former itl, it being understood that it is ordinarily used when an elliptical former is used. Viheii arranged in this way it will be seen that when the short axis of the former is toward the stone and the short aXis of the lens is against it, the long axis of the attachment is working on the lever 36 and increasing the tension so that a deeper cut will be taken at this time. v'lhis is especially desirable with convex lenses, as stated, because they will stand a deepei` out when the stone is operating on the thicker portions thereof. The chain 38 may be adjusted in any of the notches 3T for an obvious purpose.

It has been stated above that the shafts l2, 16 and 17, as Well as the gears i5 are protected from the dirt and mud. In order to carry out this idea with respect to the former il without providing a guard over it, which would be impracticable because it is necessary to see the position of this former, I have provided it with a plate 42 of sub stantially the same size and shape as the former, integrally mounted thereon, spaced therefrom and parallel therewith. This plate is shown as located between the former and :the lens which is being ground. The purpose of this plate is to enable the operator to see exactly the angular position ofthe former Without removing the mud and dirt which collects upon it. The'foi'n er is held in position on the shaft by the pin 225 entering slots therein.

In order to simplify and improve the adjusting means for the former., it is shown as made in the following way. Below the baseplate are 1brackets 50 at the bottom ofjwh ich a lever is pivoted having an upwardly extending arm 5l and a forwardly extending arm 52. On the upwardly extending. arm the lever is provided with an elongated depression in which the edge of the former Works. On the top' of the base-plate above the forward end of the arm is a dial 54 and a pointer 55; This pointer is provided with a screw 56 passing through the base` plate and controlling the position of the end of the arm 52. VIt is preferred to provide an adjusting screw 57 engaging the end of the screw 56 and mounted on the arm 52. By this construction it will oe seen thatthe turning of the pointer 55 by means of its handle 58 will adjust the end of the lever 52 and the guide 53 for the former 4l. lt is undereinem that case. It is to provide for this that the 1 lever is pivoted well down below the bottom of the case plate as indicated in Fig. 3. On account of this construction, the guide while having a swinging motion on the arc of a large circle operates almost in a straight path and the slight curve that it has is not sufficient to cause anyappreciable irregnlar ity in the grinding of the lenses, therefore, the pivoting of the lever at a point well below the base-plate and shaft. 12in an important feature.

lll'hile l have illustrated and described a preferred embodiment Vof vthe invention, l am aware that many modiiications may be made therein by any person skilled in the art without departing from the scope of the invention expressed in the claims. Therefore, l do not wish to be limited'to the particular details of construction shown, but@ lll'hat I claim is :W

l. ln a lens grinding machine, the combination of a base-plate, a frame pivoted thereA on, work holding shafts carried by said frame above the base plate, a former supported by said shafts, a lever pivoted below the base-plate and having two arms both extending upwardly therefrom, one arm thereof engaging the former, and the other arm extending under the hase-plate, and means on the base-plate for adjusting the latter arm.

ln a lens grinding machine, the combination of a base-plate, work-supporting shafts arranged above said base-plate, a lever pivoted at a distance below said base-plate and having an upwardly extending arm and ,a forward'upwardly extending arm, means `on the first named arm for controlling the position of the work supporting shafts, and

means on the top of the baseplate in front of said shafts and extending down through said base-plate, for adjusting the height of the for'wardly extending arm.

3. ln a lens grinding` machine, the combination of a base plate, work supporting shafts arranged above said base-plate, a lever pivoted at a distance below said base-plate and having an upwardly extending arm projecting above'the hase-plate from behind and a forwardly extending arm under the baseplate, means onthe upwardly extending arm for controlling the position of the work-snp porting shafts, andmeans on the top of the .baseplate in front of said shafts for adjust- -ing the height of the forwardly extending arm, said means comprising a dial on. the top of the base-plate, a pointer thereon, a screw alanis passing through the dial and base-plate and tired to the pointer, and means for adjustably connecting the end of the arin with said screw.

il. n lens grinding machine comprising work supporting shafts adapted to support a former for the work, and a lever having in the upper end thereof, a depression in its operative surface for receiving the former, the walls of said depression serving as guides for the level'. t

In a machine of the character described, the combination of two work shafts, a former, and a similar shaped guide-plate parallel with the former held between the adjacent ends of said shafts. i I

6. In a lens grinding machine, the combination of a pivoted frame, work-supporting shafts carried thereby and adapted to support a former for the work, a lever pivoted vat a distance below'l the pivot of said frame and extending upto said shafts, the u'ppe'i end of said lever'having an elongated depression. therein `for receiving the former, and meansfor adjust-ing said lever, a'former removably supported by.said shafts and a plate fixed. to said former spaced therefrom and parallel with it, said plate being of'substantially the same sizer and shape" as Ithe former. Y

'7. A former for a lens grinding' machine having integrally mountedr thereon.` and parallel therewith aplate spaced from the former and of substantially the same'size and shape as the former. Q y I S. In a lens grindingpiachine, Ithe combination of a pair of work liolding shafts, a frame for supporting said )vork 'holding shafts comprising alf pair of -l'iol/low ,cylinli-ical portions surrounding said shafts, bearings for said shafts, and two sets' of perforated felt disks on said -shafts at the ends of said bearings to protect the same from dust and dirt. I

il. In a lens grinding machine, the`conibi nation of a work-shaft, a ball retainer, a ball cone on the shaft havinga -slanting conical surface, a casing against which motion of the shaft endwise in one direction will push the balls outwardly to piment vibration, a

second work shaft toward which the larger Vend of said conical surface extends, and

means forfyieldingly forcing it toward the Y first named work shaft.

10. In a lens grinding machine, thev coinbination'bf a driving shaft, work-supporting porting sha fts and protecting them from dirt and the like, and means for connecting the last two casings with the first one, whereby said casings constitute a rigid frame for supporting and protecting said shafts, one of said work-supporting shafts having two co1- lars thereon within its casing, a spring located within the casing between said collars, and'means on the shaft for receiving the thrust of oneV end of the spring.

11. In a lens grinding machine, the combination of a longitudinally movable workholding shaft, a spring for normally moving' the shaft in onedirection, a gear fixed to said shaft, a slide rod engaging the flange of said gear, and means for'reciprocating said rod to move the gear and shaft.

12. Ina 'lens grinding machine, the conibination of a movable work holding shaft, a casing surrounding the shaft, a sprin sur rounding the sha t and located insi e the casing, for forcing the shaft in one direction, a gear on said shaft for driving it, lugs on said casing having bearings, a rod slidable in said bearingsvand adapted to engage said gear, and a lever for 'sliding said rod so as to move'the gea-r and shaft against the resistance of said spring.

13. In a lens grinding machine, the coinbination of a longitudinally movable workholding shaft, a casing inc-losing said shaft, a spring within the casin for resisting motion of the shaft in one irection, a sliding rod journaled on the outside of the casing, a gear fixed to the shaft against which the rod engages, and means for reciprocating said rod. to move the gear and shaft.

14. In a lens grinding machine, the combination of a tilting frame, work-supporting shafts jonrnaled thereon, a former carried by one of said shafts, a tension device for holding said frame in position for grinding, and a second tension device for varyingthe tension during a rotation.

15. A lens grinding machine comprising a bodily movable shaft, a former, and means independent of the former for putting said shaft under a tension of varying intensity during different portions of a single revolution.

16. In a lens grinding machine, the coinbinati'on. of a shaft, a former supported thereby, yielding means for holding the shaft in grinding position, and additional means for providing a varying tension during different portions of a revolution.

17 In a lens grinding machine, the conm bination ,oa shaft; a former carried thereby, a tensi n device, and a second tension ydevice adapted to increase the tension when the former is at such position during a revo; lution as to bring the thick edges of the lens in contact with a'v grinding stone.

18. In a lens grinding machine, .the combination of a shaft, a formercarried thereby, an attachment on the shaft adapted to be set at right angles to the former, and a tension device; acting-on said attachment for controIling the tension.

' bination of a shaft ad apted to supporJ a former thereon, an. elliptical attachment on said Shaft, a lever bearing on said elliptical 5 attachment throughout the revolution of the shaft, and ar tension device connected with the leyfer.

In testimony whereof have liereu'no set my hand, in the presence of two subscribing Witnesses.

LOUIS WILHELM. l

Witnesses R. E. FAY, C. 'FORREST WEssoN.