US1234225A - Attachment for lathes, &c. - Google Patents

Description

F. W. SICKLES. ATTACHMENT FOR LATHES, 6L0. APPLICATION mu) SEPT. 14. 1916.

Patentd July 24, 1917b 2 SHEETSSHEET I.

INVENTOR. 7M 61/. J

F. w. SICKLE'S. ATTACHMENT FOR LATHES, &c.

v APPLICATION FILED SEPT. 14. I916.

2 SHEETS-SHEET 2.

MM T- Emu lV/TNESSES: IA /TVEIVTOR. mgw 'T 41mm, flv W'W BY ATTORNEY.

Patented J 1115 24, 1917.

@TATEti PATENT FFlE FRANK W. SICKLES, 0F SPEINGFIELD, lv'IASiSAGHUSETTS, ASSIGNOR OF ONE-HALF T0 rrnoraes E. nnrrz,

OF SPRINGFIELD, MASSACHUSETTS.

ATTACHMENT FOB LATI-IES, 8w.

Specification of Letters Patent.

Patented July 2%, 1917.

To all whom it may concern:

Be it known that I, FRANK W. SIcKLEs, a citizen of the United States of America, residing at Springfield, in the county of llampden and Eatate of Massachusetts, have invented a new and useful Attachment for Lathes, &c., of which the following is a specification.

My invention relates to improvements in devices for turning, milling, or grinding contours in lathes, profiling machines, or milling machines, and resides in an attachment that is adapted to be aiiiXed to a lathe, or to a profiling or milling machine, which attachment comprises in general a bed-plate or equivalent member or support upon which is arranged to slide, under the control of parallel-motion links, a plate or carrier, means mounted on said carrier to support and feed the cutting or grinding ele ment or member, a pantograph pivotally connected at one end with said bed-plate,

pivotally connected adjacent to such end with said carrier, and provided at the opposite end with a guide member or follower, and means to support a master-form or templet against which latter said follower operates and thus directs said cutting or grinding member in the manner common to pautographs, together with such auxiliary and subsidiary parts and members as may be needful or desirable to render the at tachment complete and serviceable, all as hereinafter set forth.

The principal object of my invention is to produce a device or attachment, of the class specified above, with which it is possible and practicable to form in an efficient manner a comparatively minute piece, or to mill or grind the same, from a comparatively large master-form or templet, to the end that any error in the templet is so reduced in the piece or work that such error is negligible. For instance, if the ratio of the attachment be ten to one, or, in other words, if the pantograph of the attachment be so constructed and proportioned that the cutting or grinding member carried or actuated by said pantograph moves only onetenth as far as the templet end of said pantograph, an error in said templet will be reduced nine-tenths in the work. It is of the utmost importance practically if not entirely to eliminate errors from work of the kind now under consideration, and heretofore it has been very difi icult not to say impossible to obtain the desired accuracy, hence the great value of this feature of my attachment.

A further object is to provide such an attachment which is comparatively simple in construction and operation, is adaptable and readily applicable to a lathe or other machine in connection with which said attachment is designed to be used, and capable of being conveniently operated.

Still another object is to equip the attachment with suitable operating parts and adjusting means.

It may be observed here that the attachment is designed for use in any case where accurately turned, ground or milled shapes or forms are required in duplicate, punches for drawing cartridge shells, and needlevalves of special contour, being mentioned as two out of a large number of possible examples that fall within the above-noted general class.

Other objects and advantages will appear in the course of the following description.

A preferred form or embodiment of the invention, whereby I attain the objects and secure the advantages of the same, is illustrated in the accompanying drawings, and l will proceed to describe the invention with reference to said drawings, although it is to be understood that the construction, arrangement, shape, etc., of the parts in various aspects are not material and may be modified without departure from the spirit of the invention.

In the drawings, in which like numerals designate like parts throughout the several views, Figure 1 is a top plan of an attachment which embodies my invention as aforesaid, such attachment in this and other views being shown mounted on a lathe bed; Fig. 2, an enlarged top plan of a tool or cutter, with the holding members therefor, illustrating the manner in which such cutter is applied to the work; Fig. 3, a front end elevation of the parts shown in the preceding view; Fig. 4, an enlarged top plan of a grinding wheel, with the supporting and driving parts and members therefor, illustrating the application of such wheel to the work; Fig. 5, a front side elevation of said attachment; Fig. 6, a front end elevation of. said attachment; Fig. 7, an enlarged longitudinal vertical section through the rear end members of the attachment, taken on lines 7-7, looking in the direction of the associated arrow, in Fig. 1; Fig. 8, an enlarged elevation of the rear end members of the attachment; Fig. 9, an enlarged top plan of the cuttingor grinding-member end portion of the pantograph; Fig. 10, an enlarged detail in top plan of certain of the members at the rear end of the attachment; Fig. 11, a cross section on lines l111, looking in the direc tion of the associated arrow, Fig. 9, one of the bushings and the washer and nut above being left in elevation, and, Fig. 12, a detail showing the carrier and its post.

In Figs. 1, 5, 6, 7 and 8 a portion of a lathe bed is shown at 1, and upon th1s bedplates 2 and 3 are mounted. The bed-plate 2 is adjacent to the lefthand or front end of the lathe bed 1, and the bed-plate 3 is between said bed-plate 2 and the right-hand or rear end of said bed 1. The bed- plates 2 and 3 are secured to the lathe bed 1 and held rigidly thereon in the usual manner by means of ordinary bolts 4:, nuts 5, and washers 6.

The bed-plate 2 has an arm 8 which extends rearwardly from the back side thereof, and pivoted at 99 to said arm are two parallelunotion links 10. A post or stud 12 rises from the bed-plate 2 near the front end of the same and directly over the longitudinal center of the lathe bed 1.

A plate or carrier 13 is arranged to slide freely on the bed-plate 2, said carrier being maintained at all times in parallel relation with the lathe bed 1 by means of the paral lel motion links 10 and parallel-motion links l4.' 14: and 15. The links 14 are pivoted at their front ends to the back side of the carrier 13, at 1616, as the corresponding ends of the links 10 are pivoted at 9 to the arm 8, and the other ends of all of said links are pivoted at 17 to the link 15, which latter is a four-point link. The action of this parallel-motion is well known, and the object of the device is, as above stated, to maintain the carrier 13 in parallel relation to the bed 1, regardless of the movement or position of said carrier on the bed-plate 2, so that the front and back sides of the carrier, which in this case are parallel with each other, and the vertical center of the carrier between said sides are always parallel with the longitudinal center of said bed 1. The necessity of maintaining the carrier 33 in parallel relation to the longitudinal center of the bed 1, in the plane of which center is located the axial center of the lathe, will be made clear hereinafter. The front end of the carrier 13 is cut away at 18 to afford clearance carrier, and the for the post 12. A post or stud 19 rises from the approximate center of the carrier 13.

A pantograph has its front end pivotally mounted on the stud 12 and has at its rear end a follower or guide-roll 20, while the stud 19 is received in a cross-bar 21 which is attached to said. pantograph, said crossbar being free to turn on said last-mentioned stud. The axial centers of the studs 12 and 19 and the follower 20 are always in a ven tical plane common to all.

The levers 22 pivotally connected at 36, a pair of levers which are pivotally mounted at their forward ends on the stud 12 and pivotally attached at their rear ends to the forward ends of said levers 22, at 2t2et, and a pair of levers 25 which are pivotally attached at their forward ends to the rear ends of said levers 22, at 26 26, and pivotally connected at their rear ends by a stud or post 27. The post 27 extends above and below the levers 25. The follower or guideroll 20 is mounted to rotate on the post 27 under the levers 25, being held to said post by a screw 28 tapped into the base of the post. The guide-roll 20 rests on the bedplate 3 and slides thereon as the pantograph is operated.

An ordinary slide-rest 29 is securely clamped at 30 to the stud 19. The sliderest 29 is equipped with the usuallongitudinal and transverse feed- screws 31 and 32, respectively, and tool-post 33. A tool such as a cutter 3-1, or a grinding wheel such as that shown at 35 in Fig. 3, is carried and fed by the slide-rest 29 above the horizontal plane of the pantograph and in proper relation to the work held by the chuck (not shown) of the lathe, or the equivalent member of a profilin g or milling machine.

The crossbar 21, which forms the connection between the carrier 13 or the stud 19, with the parts supported by said stud and pantograph, is preferably adjustable. The aforesaid connection is rendered adjustable in order that the desired ratio of the attachment, or of the movement of what may be termed the executive portion relative to the follower end of said pantograph, may be obtained with absolute accuracy, and for the further purpose of enabling such ratio to be increased or decreased beyond a mere adjustment for the sake of accuracy. To this end the cross-bar 21, which extends between one of the levers 23 and that part of one of the crossed levers 22 that is diametrically opposite to said lever 23 in question, is means of bolts 37-37, washers 3838, and nuts 3939, bushings 40-et0 being introduced between said levers and said washers,

and the headed terminal portions of said bolts being received in longitudinal slots 411-411 in said levers. The bushings 10 are attached to its levers by pantograph consists of two crossed in the cross-bar 2 1, and said bushings exceed in lengththe thickness of said crossbar,'so that the bolts 37 can be secured in place, after adjustment in the slots 41, by

means of the nuts 39 and washers 38, without interfering with the pivotal action of the connected parts.

Assuming that the ratio of the attachment as now set be ten to one, by adjusting the cross-bar 21 forward of its present position and so decreasing the distance between the fulcrum (12) and the load (19), said ratio will be reduced or less than ten to one, and by adjusting said cross-bar rearward of said position and so increasing said distance, said ratio will be increased or greater than ten to one. WVithout material change the amount of possible adjustment of the cross-bar 21, over that permitted in the construction shown herewith, may be very much increased. The adjustment of the cross-bar 21 is effected simply by loosening the nuts 39, moving said crossbar to the required. extent, and retightening said nuts. The opening in the crossbar 21 for the stud 19 appears at 42 in Figs. 9 and 11.

The bedlate 3 is the support for a master-form or templet, as 43, and there is a longitudinal groove 44in said bed-plate to receive one or more pins 45 which extend fromthe underside of said templet. The pins 45 assist one or more screws 46 in holding the templet 43 securely in place on the bed-plate 3, said screws passing through said templet into tapped openings in said bed-plate. The front side edge and it may be one or both end edges of the templet 43 are those against which the guide-roll 20 rides, when the attachment is operated, and the course thus described is transmitted exactly except as to extent to the stud 19 and the cutting or grinding member carried by the slide-rest secured to said stud, through the medium of the intervening parts and members. A punch tip, such as appears at 47 in Figs. 2 and 4, can be cut and ground with the tool 34 and the grinding wheel 85, respectively, when the follower 20 is moved rearwardly over the front side edge and the rear end edge of the templet 43. i

In order to facilitate the operation of the attachment, either with the templet 43 or any other templet, whether the latter be wider or longer than the present one, or both, an operating lever 48 and adjustable means therefor are provided. Said adjustable means comprises an arm 49 which is rigidly attached at its front end to a shouldered stud 50 by means of a nut 51 on said stud, such end being tightly held between the stud shoulder and said nut. The stud 50 rises from the bed-plate 3 near the front end thereof. A series of p n g .52 is made in the arm 49, and a post or pin 53 is provided with which to connect the rear end of the lever 48 with said arm through one of said openings. A sliding block 54 is located in a longitudinal slot 55 in the lever 48, and the post 27 passes through said block. A spiral spring 56 extends between the pin 58 and the post 27 and serves normally to retain the follower 20 in contact with the working edge or edges of the templet 43, since said spring tends constantly to draw said post toward said pin, and with said post the rear end of the pantograph with said follower.

It is desirable to keep the spring 56 not only at a fairly strong tension, but also at as near an average tension as possible throughout the arc of travel of the follower 20, such arc being determined by the working edge or edges of the templet, and both of these ends I am able to attain by means of the arm 49. The tension of the spring 56 may be increased or decreased by loosening the nut 51 and swinging the arm 49 rearwardly or forwardly, said nut is retightened, or by moving the pin 53 toward the rear end or toward the front end of said arm, accordingly, or by both of these methods; and similarly may the necessary adjustment or adjustments be made to average said tension to the arc of travel of the follower, and properly to position the lever 48 relative to such are.

The arm 49 is the fulcrum for the operat ing lever 48, and as the latter is swung on the pin 53 the block 54 slides in the slot 55 and thefollower 20 on the post 27 is caused to travel along the templet or to move over the templet course.

The cutting tool 34 is cylindrical and the periphery of the grinding-wheel 35 is trans versely convex. The ratio between the diameter of the tool and that of the guideroll 20 corresponds to the ratio of the attachment; so, also, with reference to the transverse curvature of the periphery of the 'rinding-wheel and the attachment ratio. If, therefore, the attachment ration be ten to one, the guide-wheel or follower diameter will be ten times greater than the tool diameter or the grindingwheel transverse peripheral curvature. In the absence of these proportions or corresponding ratios the tool or grinding-wheel would not be able to do its work properly, because there would be a descrepancy between the movement of the follower and that of the tool or grindingwheel.

The tool 34 is affixed at the rear end of a bar which latter is adapted to be clamped into the tool-post 33, there being a tongue and-groove connection between said tool and bar, as represented at 58 in Figs. 2 and 3, and a clamp-rod 59to secure said tool rigidly to bar. The c amp-r d 9 passes accordingly, when ing-wheel is attached.

through the bar 57, has at its rear end a head by means of which a tongue-and-groove connection is formed with the tool 34:, as shown at 61, and is provided at its rear end with a nut 62 to draw said rod with said head forward and so clamp the tool to said bar.

Relative rather than actual conditions as between tool and work obtain in Fig. 2, and

the same may be said of the grinding-wheel and work in Fig. 4.

The grindingwheel 35 is mounted on a spindle 63 which is journaled in a head 6% at the rear end of a bar 65, said spindle with said grinding-wheel being driven by a pulley 66 on said spindle and a belt 67 on said pulley; The bar like the bar 57 is receivable in the tool-post 33.

The operation of the attachment as a whole will be generally understood from the foregoing, but may be briefly described as follows: Firstthe required templet is placed in position, any adjustments that may be necessary are made, and the tool or grindera-ting lever 48 isswung well forward or to the left so as to locate the follower '20 against a more forwardly-projccting or advanced part of the templet and the tool or grindingwheel out of the path of the work,

the latter is placed in position and set in The lever 48 is now swung to the motion. right and the follower is carried with it. The follower rides against the templet and, through the medium of the pantograph and connected and associated parts and members, causes the tool or grinding-wheel to assume to the work exactly the same relation that said follower assumes to said templet, except in distance of travel, with the result that the work is shaped toconform to the shape of the templet. If the advance end of the work is to be cut or ground, the spring 56 causes the follower to turn the righthand front corner of the templet, however sharp, and to ride against the rear end edge of said templet. Further operation of the attachment is amere duplication of what has already been explained. a

The presence of the parallel-motion links insures the constant position, of the sliderest and the cutting or grinding member carried thereby, relative to the longitudinal lathe oromachine center and to the work, that is required in order that the results produced by the attachment shall always be adequate, practical, and accurate in all respects. 7

It is now seen that the attachment is capable of turning out or accomplishing economically and expeditiously accurate and satisfactory work which does not vary one piece from another. thermore, is capable of a wide application.

Then, while the op- I The attachment, fur- The tool, cutting, grinding, or other me1nber which operates directly on the work may be classed as a working element and is so termed in the claims. I

lVhat I claim as my invention, and desire to secure by Letters Patent, is-

1. An attachment, of the class described, comprising a support, a member arranged to slide freely in any direction on said support and equipped with means for carrying a working element, a pantogra'ph pivotally attached at one terminal, and provide-d at the other terminal with a master-form follower, said pantograph being pivotally connected with said sliding member, and par allel-motion members adapted partially to control the movement of said sliding member.

An attachment, of comprising a support, a member arranged to slide freely in any direction on said support and equipped with means for carrying a working element, means to maintain said member with its diameters respectively par allel with and at rightangles to the longitudinal center of the lathe or machine with which said attachmentis used, at all times, and a pantograph pivotally attached at one terminal, and provided at the other terminal with a 1nasterform follower, said pantograph being pivotally connected with said sliding member at a point between its pivotal terminal and said follower. v

3. An attachment, of the, class described, comprising a support, a member arranged to slide freely in any direction on said support and equipped with means for carrying a working element, a pantograph pivotally attached at one terminal, and provided at the other terminal with a master-form follower, an adjustable pivotal connection between said sliding member and said pantograph at a point between its pivotal terminal and said follower, and parallel-motion members adapted partially to control the movement of said sliding'member.

4. An attachment, of the class described, comprising a movable member equipped with means for carrying a working element, a pantograph pivotally attached at one terminal, and providedat the other terminal with a master-form follower, said pantograph being pivotally connected with said movable member, s and having its follower terminal yieldingly held in contact with the master form.

5. An attachment, of the class described, comprising a movable member equipped with means for carrying a working element, a pantograph pivotallyattached at minal, and provided at the other terminal with a master-form follower, said pantograph being pivotally connected with said movable member, and an adjustable operating handle for said pantograph,

the class described,

one terb. An attachment, of the class described, comprising a movable member equipped. with means for carrying a working element, a pantograph pivot-ally attached at one terminal, and provided at the other terminal a with a master-form follower, said pantograph being pivotally connected with said movable member, a spring arranged to act on the follower terminal of said pantograph to retain said follower in contact with the master form, and adjustable means to increase or decrease the tension of said spring.

7. An attachment, of the class described, comprising a movable member equipped with means for carrying a working element, a pantograph pivotally attached at one terminal, and provided at the other terminal with a master-form follower, said pantograph being pivotally connected with said movable member, an operating handle for said pantograph, a spring arranged to act on the follower terminal of said pantograph to retain said follower in contact with the master-form, and adjustable means for said handle and spring.

8, In an attachment, of the class described, a pantograph having a given ratio, and provided with a mastenform follower, and a movable member actuated by said pantograph and equipped with carrying means for a working element, the diametrical ratio between said follower and the working surface of such working element corresponding with the ratio of said pantograph.

9., The combination, the class described, with a. support, a cuttingor grinding-element carrier arranged to slide on such support, parallel-motion links partially to control the movement of said carrier, and a master-form support, of a pantograph pivotally mounted at one ter minal on said first-mentioned support, and provided at the other terminal with a master-form follower, said pantograph being pivotally connected with said carrier.

10. The combination, in an attachment of the class described, with a support, a carrier arranged to slide on such support, and provided with a stud, a slide rest mounted on said stud, and a master-form support, of a pantograph pivotally mounted at one terminal on said first-mentioned support, and provided at the other terminal with a master-form follower, and a crossbar attached to said pantograph and pivotally mounted on said stud.

11. The combination, in an attachment of the class described, with a support, a sliding carrier on said support, such carrier having a stud, and a master-form support, of a pantograph pivotally mounted at one terminal on said first-mentioned support, and provided at the other terminal with a port, and provided at in an attachment of master-form follower, and a cross-bar adjustably attached to said pantograph and pivotally mounted on said stud.

12. The combination, in an attachment of the class described, with asupport, a sliding carrier on said support, and a master-form support, of a pantograph pivotally mounted at one terminal on said first-mentioned supthe other terminal witha post, a master-form follower on said post, an arm affixed to said second-mentioned support, and an operating lever pivotally connected with said arm and with said post.

13. The combination, in an attachment of the class described, with a support, a sliding carrier on said support, and a master-form support, of a pantograph pivotally con nected at one terminal with said first-men tioned support, and provided at the other terminal with a post, a master-form followeron said post, an arm affixed to said secondmentioned support, and an operating lever pivotally connected with said arm, said lever being slotted to receive said post.

1%. The combination, in an attachment of the class described, with a support, a sliding carrier on said support, and a master-form support, of a pantogra-ph pivotally connected at one terminal with said first-1nentioned support, and provided at the otherterminal with a post, a master-form follower on said post, an arm adjustably affixed to said second-mentioned support, and an operating lever pivotally connected with said arm, said lever being slotted to receive said post.

15. The combination, in an attachment of the class described, with a support, a sliding carrier on said. support, and a master-form support, of a pantograph pivotally connected at one terminal with said first-med tioned support, and provided at the other terminal with a post, a master-form follower on said post, an arm afixed to said secondmentioned support, and an operating lever pivotally and adjustably connected with said arm, said lever being slotted to receive said. post.

16. The combination, in an attachment of the class described, with asupport, a sliding carrier on said support, and a master-form support, of a pantograph pivotally connected at one terminal with said first-mentioned support, and provided at the other terminal with a post, a 1nasterform follower on said post, an arm afliXed to said secondmentioned support, an operating lever slotted to receive said post, a pin pivotally to connect said lever with said arm, and a spring between said pin and said post.

17. The combination, in an attachment of the class described, with a support, a sliding carrier on said support, and a master-form support, of a pantograph pivotally concarrier on such nected at one terminal with said first-men tioned support, and provided at the other terminal with a post, a master-form follower on said post, an arm adjustably aiiiXed to said secondmentioned support, an operating lever slotted to receive said post, a pin pivotally to connect said lever with said arm, and a spring between said pin and said post.

18. The combination, in an attachment of the class described, with a support, a sliding carrier on said support, and a master-form support, of a pantograph pivotally connected at one terminal with said first-mentioned support, and provided at the other terminal with a post, a master-form follower on said post, an arm affixed to said secondmentioned support, an operating lever slotted to receive said post, a pin pivotally to connect said lever with said arm, means to enable said pin to be adjusted relative to said arm, and a spring between said pin and said post. a

19. The combination, in an attachment of the class described, with a support, a sliding support, and master-form support,of a pantograph pivotally mounted a tone terminal on said first-mentioned support, and provided at the other terminal with a post, a master-form follower on said post, an arm adjustably afiiXed to said second-mentioned support, an operating lever slotted to receive said post, a pin pivotally to connect said lever with said arm, and means to enable said pin to be adjusted relative to said arm.

20. The combination, in an attachment of the class described, with a support, a sliding' carrier on such support, and a masterform support, of a pantograph pivotally connected at one terminal with said firstmentioned support, and provided at the other terminal with a post, a master-form follower on said post, an arm adjustably affixed to said second-mentioned support, and a spring between said arm and said post.

21. The combination, in an attachment of the class described, with a support, a sliding carrier on such support, and a masterform support, of a pantograph pivotally mounted at one terminal on said first-mentioned support, and provided at the other terminal with a post, a master-form follower on said post. an arm aifixed to said second-mentioned support, and a spring at tachable to said post and adjustably attachable to said arm.

22. The combination, in an attachment of the class described, with a support, a sliding carrier on such support, and a master-form support, of a pantograph pivotally mounted at one terminal on said first-mentioned sup port, and provided at the other terminal with a post, a master-form follower on said post, an arm adjustably afliXed to said second-inentioned support, and a spring attachable to said post and adjustably attachable to said arm.

23. The combination, in an attachment of the class described, with a support, a sliding carrier on such support, and a master-form. support, of a pantograph pivotally mounted at one terminal on said first-mentioned support, and provided at the other terminal with a post, a master-form follower on said post, an arm adjustably affixed to said second-mentioned support, an operating lever slotted to receive said post, a pin pivotally to connect said lever with said arm, means to enable said pin to be adjusted relative to said arm, and a spring between said pin and said post.

. 24. An attachment, comprising a support, a member arranged to slide freely in any direction on port, said member being equipped with means for carrying a working element, a master-form, a master-form follower of a size which is a multiple of the size of said working element, and of a shape which cor responds proportionately with the shape of said element, actuating means for said sliding member, such means being connected with said movable member and having said follower connected therewith, and parallelmotion members adapted partially to control the movement of said first-mentioned member.

25. In an attachment, of, the class described, a movable member equipped with means for carrying a working element, a master-form, a master form follower of a size which is a multiple of the size of said element, actuating means for said movable member, said means being connected with said movable member and having said follower connected therewith, and means to maintain said movable member with its diameters extending in the same directions at all times, regardless of the position given said member by said actuating means.

26. In an attachment, of the class described, a movable member equipped with means for carrying a working element, a master-form, a master-form follower of a shape which corresponds with the shape of said element, actuating means for said movable member, said means being connected with said movable member and having said follower connected therewith, and means to maintain said movable member with its diameters always extending in the same directions, regardless of the position given said member by said actuating means.

27. in an attachment, of the class described, a movable member equipped with means for carrying a working element, a master-form, a master-form follower of a size whichis a multiple of said element,

of the class described, I

said sup- I and of a shape which corresponds proporalways extendingin the same directions, tionately with the shape of said element, acregardless of the position given said memtuating means for said movable member, ber by said actuating means. said means being connected with said mov- FRANK W. SICKLES. 5 able member and having said follower oon- Witnesses:

nested therewith, and means to maintain F. A. CUTTER,

said movable member with its diameters A. G. FAIRBANKS.

Gopies of this patent may be obtained for five cents each, by addressing the oommissioner of Patents, Washington, D. G.

Images