US2610389A - Power saw for cylindrical printing plates - Google Patents

Description

Sept. 16, 1952 a, w, BUNGAY 2,610,389

POWER SAW FOR CYLINDRICAL PRINTING PLATES Filed Nov. 29, 1949 B Shoots-Sheet 1 INVENTOR. 650mm M Bu/vG/n A TTORNEYS.

Sept. 16, 1952 5, w, BUNGAY 2,610,389

POWER SAW FOR CYLINDRICAL PRINTING PLATES Filed Nov. 29, 1949 5 Sheets-Sheet 2 INVENTOR.

650E615 h! EU/VGAY A TTOfFNEYS Sept. 16, 1952 c. W.BUNGAY POWER SAW FOR CYLINDRICAL PRINTING PLATES 5 Sheets-Sheet 3 Filed Nov. 29, 1949 INVENTOR. Geo/ea: M Bu/ve/n A TTO/PNEYS.

Sept. 16, 1952 e. w. BUNGAY 2,610,389

POWER SAW FOR CYLINDRICAL PRINTING'PLATES Filed Nov. 29, 1949 5 Sheets-Sheet 5 INVENTOR. 65052;: W Bu/vam A TTORNEKS.

Patented Sept. 16, 1952 -"row t; i ro remo e? The present invention relates/to a novelfand improved motor driven saw for "sawing -cylindri-: cal printing plates along edgesprior to the finishing -operation.

Objects and advantages of the invention will beset forth in part hereinafter and in part will be obvious herefrcm, or may be learned by practice with-the invention, the same being realiZed-and attained by means-of the instrumentalities and combinations pointed outin the appended claims.

Theinvention consistsin the novel .iparts, constructions, arrangements, combinations and improvements herein shown and described. The-accompanying drawings, referred to'h'erein and constituting a part hereofinillustrate one embodiment of the invention' and together .with the description, serve to explain the principles of "the invention. Y 'H Of the drawings:

' Figure l .is a side elevationjcf a typical and illustrative embodiment of the present invention;

Figure 2 is a .front elevation lacking from the right of Figure 1; .l a i 1 -Fi'gure 3 is aideta'iled elevationshowing the clutch mechanism and fluid pressure motor :for holding the plate while it is sawed; I

Figure 4 is a detail horizontal section taken on'zthelin'e 4-'- ,4"of Figure 2; t

:Figure 5 is :a; horizontal section. taken onfth'e line :5-\-.5 of Figurefl; Y

.Fig'ure 6is1a fragmentary vertical section taken on'the lineE-i-fi of Figure 5;

V'Eigure lislasectional .view takenton the line 1-1 of Figure 6 showing the internal structure of the clutch and reversing gears; V igure 8 is a sectional viewta-ken on theline 8- 8-of Fi ure'hand, r I

Figure 9 is adetailed elevation showing vthe clutch operating levers inneutral position.

The present invention has for itsobj'ect the provision of a novel, and improved cylindrical plate'saw for sawing curvedstereotypes andelectrotypes. A further object is the provision .0f.:a' power saw which may be rapidly ,operatediwith'a minimum of manual efiort, and produces accu- I trativelyembodied.intmechanism comprising at their straight parallel rately; sawed -plateswith complete certainty. ;A

further object is theprovision of a platejsaw which will operate with equal accuracy'on plates of widely different diameter. The invention-further provides-a power saw of;the kind set forth in which the plate is supported vertically ona flattable and maybe easily lifted .to and from the saw table. V a

The-power-saw of the present invention is-il-lusflat table onwhich: the curved plate ;is supported with oneofwits cilrvededges resting ongthe flat surface. A pair of guide rods, close together and parallelxto each-other are perpendicular to the table andserve to'accurately position the plate so that the *saw passing-between them ,cutsthe plate along radial straight edgesaccurately per: pendicular to the plane ofthe' curvededges; A clamping. memberis power moved along the guide rods so as to olam'p the plate between it and the table. .The saw'isrpower driven. by "a "vertically movable motor on guideways' which carry a frame supporting. both: the saw and motor. -A leadi'screw is.;a:lso motor driven through-a clutch and reversing gearso'that the saw and i'ts:motor are lowered andxraiseiby the-elevator'lm'otor. Auto matic .means are provided-for controlling the travel of the motoredriven saw; After one straight edge of the v ;plate has been sawed, the clamp is .released,;th'e;plate shifted, again clamped and the second cutistaken and is, parallelgtothe It :will be understood thatsthe; fioregoing general description: and the following detailed description as well are-exemplary and explanatory of "the finventiongbut are 1 not restrictive thereof.

jiReferring inowcin {detail .to the illustrative ,e m bodiment of the presentiinventionrasyshown specifically in the. accompanying drawings, there is provided-a heavy rigidbase 10 one part of which isfinished to providea flat horizontaltable l2 adapted tor eceive the curved, 'uniplanar edge M ofv a partigcylindrical stereotype, velectrotype orzother rigid arcuategprinting plate It which is to have its straight parallel edges trimmed to provide radial surfaces by which the plate may beclamped to -;the cylinder duringprinting. The curved edges M ofthe plate 16, as cast orotherwise formed, {are generally trueand form ,the reference surfaces by which the Qtheredgesmay be'trimmed, o

M ans arenrovided for accurately locatingthe plate,;so that the plate may be accuratelyzzpositioned with the saw blade on its radius.

Table I2 is formedwithan edge-slot 18 wide enough to provide clearance for :a :jcircular'saw blade and deep enough .to receiveizthesawiblade far enough to cut through the-plate. Closely adjacent the sloth-l8 .are'two parallel, rods 1120 fixed. in the tablefsurface lief base. [In and extending upwardly therefrom; The :exteriorrof these cylindrical rods Iform rsurfacesflto' :contact with :the convex surface of the plateilifi ofany normal size, so a radius of the plate l5 :liesmver 3 the slot I8 and is uniformly spect to the saw blade.

Means are provided for clamping the plate [6 during the sawing operation. As embodied, a flat clamping member 22 is movable up and down along rods 26 at their portions of reduced diameter. Clamp 22 is preferably power actuated by means of a, reversible fluid pressure motor 24 under control of a normally actuated reversing valve 26. The reversing valve 26 controls the positioned with resupply of fluid pressure from supply pipe 36 to the pipe 3| or 32 connected to the upper and lower ends of the motor cylinder 24 so as to lower or raise (respectively) piston rod 34 which is connected to the cross head 36 which'is oppositely slotted at its ends and is engageable in the grooves 38 formed along the length of the slidable rods 39 which are connected to the clamp 22. The clamp 22 is provided with hand grips 46 at its ends and is apertured to slide on the guide rods 20, while the upper ends of the rods 39 are slidable in the upper guide plate 42. To insure the proper looking of the cross head 36 in the grooves 38," a leaf spring 44 is secured to the cross head and tends to pull the slotted end into the groove 38. On the other end, a stop 46 is provided to prevent the cross head being swung too far so as to endanger breakage of the spring 44.

By manually lifting or lowering the clamp 22 while the cross head 36 is swung by handle 31, the clamp may be adjusted so as to be power actuated from plate released to plate securing position for all normal lengths of plates.

The motor driven saw is carried on a vertically movable frame and the saw rotates in the same pathas itis bodily moved. As embodied, a slide 50 is movable up and down along a dovetail guideway 52, and is gibbed thereto. On one side, the slide is formed with suitable bearings for the saw shaft 54 on one end of which is mounted a circular saw blade 56, while on the other end there is provided a double pulley 58. A suitable saw guard 60 is mounted on the slide 50 to cover the saw except where the saw passes into slot I8.

A motor 62 drives saw pulley 58through belts 64 and is mounted on a plate 66 supported on the slide'50 by means of the rigid rods 68, the motor being so positioned that the vertically movable saw and motor are substantially balanced about the guideway '52 so that any tendency tobind is avoided. A suitable power supply and switch are'provided for motor 62. a e

For moving the motor-saw unit up and down, power means are provided for slowly moving the saw down as it cuts the plate and for more rapidly moving the saw upwardly on its idle return stroke. As embodied, a motor I0 is mounted on the upper end of the column 12 which supports guideways 52. Motor I0 drivesa'bevel pinion 14 through reduction pulleys I6 so' as to drive two compound gears I8 and 80. g

A threaded rod 84 extends vertically parallel to the guideways 52 and engages with a threaded sleeve 86 fast to the slide 50 so that rotation of the rod 84 raises orlowers the slide 50 and the motor 62 and saw 56 carried thereby. Rod 84- is journalled at its upper end in bearings 88 in the gear box in which the gears I4, I8 and 89 are rotatably mounted.

Reversible clutch means are'provided for driving rod 84 from gear I4 and for this purpose a dog clutch member 92 is slidably keyed to the rod 84 at its upper unthreaded end. Member 92 may be moved upwardly into driving engagement with the clutch member 94 formed integrally with a edge of the metal plate.

gear journalled for rotation on shaft 84 and meshing with the spur gear portion of compound gear 16. Gear 18 and gear 94 form a speed reducing pair and slowly drive the threaded rod 94 so as to slowly lower the saw as it cuts the Below clutch member 92 and cooperating with the lower face thereof is another gear 96 so that the rod 84 may be driven faster in the opposite direction, gear 96 meshing with the spur portion of the compound gear 88, gears and 96 forming a speed increasing unit whereby the rod 84 is turned faster and in an opposite direction than by gears I8 and 94. In the position shown in Figure 7, clutch member 92 is in neutral position and rod 84 is stationary holding the saw against vertical movement.

For shifting the clutch from neutral to either up or down motion of the saw, a fork 98 has pins 99 which run in an annular groove in the clutch member 92. Fork 98 is pivotally mounted on shaft I III] and may be swung by handle IOI so that clutch member 92 engages with either gear 94 or 96 or with neither.

Means are provided for holding the clutch in any of its three positions and for returningthe clutch to neutral position from .either of its other positions when the saw has reached a definite point in its vertical travel. For this purpose, a fork I63 is'keyed to shaft I00 and has flat ends which are engageable with a roller I04 carried by an arm I96 spring urged into contact with one of the flat ends of fork I63 or with the notch between the forked end. Thus the spring and roller I04 tend to holdthe clutch in any position until it is pushed manually or otherwise to another position.

Variably positionable stops are provided for engagement with the motor saw sliding-unit to release the clutch to neutral position as it reaches a predetermined point in its vertical travel. Vertical rod I'III extends parallel to the guideways 52 being supported at its lower end in a guide plate I I2 and pivoted at its upper end to a bell crank H4 keyed to shaft I00. At its lower end, rod HO has a coil spring H6 compressed between collar I I8 and plate I I2.

Rod H8 passes through an eye I20 carried on one of the rods 68. Eye I20 is adapted to contact with collar I22 near the bottom of rod I I I] and as the saw moves upwardly with. a movable collar I24. Collar I24 has a radial pin I26 which is spring pressed to engage with one of the holes I 28 formed in rod I I0,.while collar I22 has a set screw to hold it in the desired vertical position.

As soon as eye I20 engages with collar I22 or I24, travel of the saw as driven by motor 70 causes rod I I6 to be moved thereby swinging the fork 98 and the clutch member 9 2 towards neutral position, which movement is assisted in its later stage by the spring pressed roll-er I04.

In operation, clamp 22 is adjusted to the proper height by hand lever 36 and after plate I6 has been seated against rods 20 on the faceof table I2, valve 26 is moved to force the clamp 22 powerfully against the upper curved edge of the plate thereby securely clampin the plate with saw blade 56 radial with respect to the plate, regardless of its diameter. l Motor 62 and motor III are then energized and clutch lever "II is pushed up to'cause the'saw to travel downwardly until eye I 20 engages stop collar I22-to stop downward travel of the saw. During its downward travel, the saw cuts one straight edge of the curved plate I6. Lever IOI is then pulled down and the saw is rapidly raised until eye I20 engages collar I24 to restore the clutch to neutral.

Clamp 22 is then released by valve 26, the plate H5 is shifted so that it is in position for its other straight edge to be sawed and the operations are repeated for sawing that edge, thereby severing the cylinder into a plurality of curved plates.

The invention in its broader aspects is not limited to the specific mechanisms shown and described but departures may be made therefrom within the scope of the accompanying claims without departing from the principles of the invention and without'sacrificing its chief advantages- What is claimed is:

1. Apparatus for mechanically sawing the straight edges of a parti-cylindrical printin plate including in combination a flat horizontal table, a pair of parallel rods rigidly mounted on and normal to the surface of the table, a saw slot in the table surface between the rods, a power driven saw, and means guiding the saw in a path parallel to the rods, said parallel rods being engageable with the convex surface of the plate to locate the plate on the table in a definite relation to the path of the saw.

2. An apparatus as claimed in claim 1 in which power means slidable on said parallel rods are 6 provided for holding the plate firm against the table.

3. Apparatus for mechanically sawing the straight edges of a parti-cylindrical printing plate including in combination a fiat horizontal table to receive the plate while standing on a curved edge, a pair of parallel rods normal to the table surface, a saw slot in the table surface between the rods perpendicular to a line through the rods, a power driven saw movable vertically and parallel to the rods, said rods forming stops engageable with the convex surface of the plate to position the plate with the saw radial thereto and separate power means for moving the saw in either vertical direction.

GEORGE W. BUNGAY.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,387,869 Royle Aug. 16, 1921 2,372,818 Dostal Apr. 3, 1945 FOREIGN PATENTS Number Country Date 6,701 Great Britain Mar. 18, 1913

Images