US2198716A - Pantograph engraving machine - Google Patents

Description

30, F. ACKERMAN ET AL 2.198.716

PANTOGRAPH E NGR AVING MACHINE Filed Feb. 7, 1939 2 Sheets-Sheet 1' I7 AT'rORSI-ZY Patented Apr. 30, 1940 UNITE meant rnnroonnrn uneas /mo MAomNE Frank Ackerman, Bronx, and Herman Gould,

Brooklyn, N. Y.

Application February '7, 1939, Serial No. 255,020

6 Claims. (oi. 33-25) specified adapted for reproducing by engraving,

characters from type or stencils or facsimile signatures onto fiat or slightly curved objects,

such as cigarette cases, compacts, vanity cases and the like, formed of metal, plastics, hard rubber, enamel ware and the like. A further object is to provide such machine wherein the pressure of the engraving cutter upon the Work is maintained substantially uniform so that the depth of the engraving cut will be substantially uniform regardless oi the character, form or any irregularity in the object being engraved. A further object is to provide apantograph wherein the pivotal connection between certain arms 20 thereof is such as to permit slight relative movement therebetween in a direction perpendicular to the common plane of said arms... A further object is to provide such machine which will be simple in construction and which can be effi- 25 ciently operated by an unskilled worker aftera few minutes instruction.

The foregoing and other objects not specificallyenumerated are accomplished by our present invention, the construction and operation of .30 which will be understood from the detailed descriptionwhich follows when considered in cor1- nection with the accompanying drawings, wherein: Figure 1 is a top plan view of an engraving 35 machine embodying our invention.

Fig. 2 is a side elevation of the machine shown in Fig. 1, when viewed from the right. thereof, parts of said machinebeing broken away to better illustrate certain details of construction. 40 Fig. 3 is a section taken substantially along the plane of the line 3-3 of Fig. 1. r.

Fig. 4 isasection taken substantially along the plane of the line 4-4 of Fig. 1.

Referring to the drawings, let ill indicate a 46 supportingbase which is preferably in the form of ahollow truncated rectangular pyramid having at one corner thereof anupright or standard it having an offset portion it provided with. an

clamping relation thereto by a bolt is is split clamping ring l6 which supports an electric motor 17 having a shaft l8 extending in averticaldiw e a d avi P ller answerer Extending upwardly through the base it and through the overhanging lug it is a threaded bolt 20 which constitutes a fixed pivot for a pantograph, the supporting arm 2i of which is held upon the bolt it between the lug it and a sleeve 22 which in turn is held in position on the bolt (Why a nut 23. The pantograph supporting arm intermediate its endshas pivoted thereto a sec- {0nd pantograph arm is which at its end remote from the pivotal connection extends upwardly and reversely over the arm to provide a U-shaped support 24a for a cutter unit25. Pivotally connected to the free end of the pantograph supporting arm 2!! is a. third pantograph arm 2% which is longer than the other arms and at its free end carries a tracing stylus 2i. Pivotally connected to the outer end of the second arm 24 and to a point intermediate the ends of the third arm 26 is a fourth pantograph arm 28.

The cutter unit may be of any preferred a 20 construction, such for example as described in detail in our co-pending application, Serial No. 248,032, filed December 1938, and consists of an axially rotatable cutter element adapted to be rotated by a driven pulley 229 in a manner to be.25 described. 1

Coairially mounted with the pivot pin connecting the arms 2i and Ed is a pair of pulleys 35d and St, the latter being driven by an elastic belt 32 from the motor pulley l9, and the former being- 30 adapted to drive the cutter of the cutter unit 25 through a belt 33. Preferably the shaft 58 of the motor ll is disposed substantially in the common vertical plane passing through the pivotal axes of the pantograph supporting arm 2i so as to impose but a slight pull on said arm by the driving belt 32 when the central pivot of said arm and limit the extent of the pivotal rotation-of the pantograph supporting arm about its fixed pivot 20, lugs 3d are mounted on the arm 2! for engagement with the edges of the offset portion ll? of the standard ll..

Mounted below the horizontal sweep of the cutter unit is a work support which consists of a fiat plate 35 having a pair of parallel slots 36 adjacent opposite edges thereof and disposed in each of said slots is an upwardly extending screw 3i which supports a clamping bar 38 which is normally biased away from the plate 35 by coil springs 39 mounted upon said screws. The

on the plate 35 by wing nuts 40.

7 tubular cylindrical members 42, the said cylindrical members being normally biased to move apart by coil springs 43 and are limited in such movement by connecting bolts 44. The telescoping members are held'against relative axial rotation through the medium of a key 45 carried by the member 42 and moving in a keyway 46 in .the member 4|. It is also desirable to prevent the bolts 44 from rotating once they'ihave beenadjusted and forthis purpose set screws 4'Lmay be mounted in the bases of the members 42 adjacent the hexagonal head of the bolt 44. The telescoping sleeves which support the plate 3 5 are mounted for movement. in cylindrical bosses 48 formed in the top of the supporting base 10.

Normally the, action of gravitywcausesthe.work supporting plate to move to .a position remote from the cutter and to bring an article whichis mounted on said supporting plate into-engraving relation .to the cutter, itis neoessary'to movexthe work support upwardly. .To accomplishthis we provide an operating shaftz4-9 which is journalle'd -in-bosses50 formedionopposite sides of the supporting base, said shaft having mounted thereon .a finger 5! which isadapted when the shaft l9 is-rotated to engage a connecting rod 52 which joins the cylindrical members 42 to move the same upwardly. For rotatingsaid shaft it is provided with an operatingarm 53 having at its outer end a handle 54.

Since the articles to be engraved-by the machine :are not all of uniform thickness it willbe apparent that the degree of upward movement holding the screw'fi'l in adjusted position. .It'will thus be apparent that themovementof the operating arm 53 downwardly untilit contacts the which above'the base is fixed, and toaccomsuch that the sleeves4l are capable of limited plish this thetelescoping sleeves 4-l and-42 are movement against the tension 'of the springs when subjected to pressure,notwithstanding that the sleeves 4'2 areheld against downward-movement.

In the use of the pantograph the application of strains to the operating arm 26 especially in a vertical direction imposes a certain amount of strain on the pivotal connections which if not taken up will soon either cause a bending of the pivots or of the operating arm 26. To prevent such injury taking place we form the pivotal connections so as to permit limited movement between the connected arms in a directionnaxially of the pivot pins. The specific construction of .ing cut in the article.

these pivot connections as provided at the pivots 59 and BI] are of a form as shown in detail in Fig. 4, wherein the pivotal connection between the arms 26 and 28 is provided by telescoping coaxial bushings on spacing washers 6i and B2, and coaxially with which extends a headed pin 63' having a spring 64 mounted thereon between the head of the pin and the arm 26, said pin being held in. position by a cotter pin 6.5. Preferably the spring enclosed portion ofthe pin is housed within a dome washer 66 mounted on the pin. A substantially equivalent resilient pivotal lower end of the pivot pin between the underfaceof thearm '28 and a washer 68.

For supporting a templet or facsimile which is to be reproduced by engraving on an article, there is mounted on the supporting base 10 through a pair of spaced uprights 10 a platen H having thereon suitable guide \waysg-for-zreceiving the templet or facsimile containing sheetwanda. pair of slidable clamps II-.eachyprovidedwith a spring clip "I13 adapted atciholdsa-idqtemplet or facsimile sheet in place. For holding-the slidable clamps in fixed relation 1 thumb-screws 1.4;:maybe employed. For controlling the X operation of $116 electric motor I! a snap switchJ5-may-be:mounted at the front of the base In the operation of -the-machinepthe article, for example a cigaretteucase J6,:isplacedpn-the supportingplate '35 and clamped thereon through the medium of the clamping bar 38 -and wing nuts). The limiting means BBare-then-adjuSted to limit the upward movementof-.the*supporting plate to govern the-proper depth forethe-engrav- The templetaorthe facsimile containing sheet is then posi-tioned a-an'd held onthe platen. The stylusiJ-is thenebrough-t over into position at the left handeend of the matter to be copied andone is-nowready tog-proceed with the engraving operation. To accomplishthis the motor is .startedby-throwing :the switch 15, the work supporting base with the cigarette case thereonis elevated. bypressing the handle 54 downwardly until the -arm F53.c;ontacts with the head. of the screw t1 and-thevstylus is then moved over the matterto becopied. Where a blank "is encountered or =where.itais desired to dot (an i .or crossla t it will be apparentthat pressure on the .handle will be released so as to permit the worktomoveoutof engagementwith the cutter until the stylus has been again-moved into proper. copying-position. When the-engraving operation is completed the handle .54 .-is. released whereuponithe springs I43 eagain move .-.the work support downwardly,,.the clamping bar .is then released, the engraved .article.=.is removed, brushed and .finishedin the conventional manner.

While we have shown and describedia preferred embodiment of ourinvention it..is.to..be understood that We do not wish'to be llrriited to the specific details of construction disclosed, since thesemay be varied within therangeof engineeringskill without departing fromthe spiritof the invention. I

What we claim is:

1. In a pantograph .engraving .machine.or the like, a gravity actuated work-supportlforholding the article to be engraved by the cutter, guide means within which said work support is movable, manually operable .means for .moving the work support upwardly toward the cutter against "the action of gravity and adjustable means for limiting the "movement of the work connection is provided between the arm 24 and the arm 28 wherein a spring 61 is mounted at the support toward the cutter, said work support comprising a pair of relatively movable members and resilient means between said members whereby one of them is rendered capable of moving relatively to the other away from the cutter after the work support is moved to its adjustable limiting position toward the cutter.

2. A pantograph-engraving machine according to claim 1, wherein the relatively movable members of the work support are a pair of telescoping elements which are acted upon by the resilient means.

3. A pantograph engraving machine according tojclaim 1, wherein the relatively movable mem bers of the work supportare a pair of telescoping elements which are acted upon by the resilient means, and wherein the upper of said elements carries a work supporting plate, the telescoping elements being so related and the tension of the resilient means being such that the manually operable means in acting upon one of the telescoping elements operates through the resilient means to move the other telescoping element and the work supporting plate toward the cutter. i

4. In an engraving machine or the like, a pantograph comprising a plurality of pivotally con- 5. In an engraving machine or the like, a work support comprising a substantially flat plate, a clamping bar carried by and extending across said plate, resilient means normally biasing said clamping bar away from the plate and means for holding said clamping bar in engagement with an article tobe engraved.

6. In an engraving machine or the like, a work support comprising a substantially flat plate hav ing a pair of slots therein, screws extending through said slots, a clamping bar mounted on said screws and extending across said plate, coil springs mounted on said screws and normally biasing said clamping bar away from the plate and nuts adjustable on said screws for limiting thebiasing action of the springs.

FRANK ACKERMAN. HERMAN GOULD.

Images