US2341929A

US2341929A - Lithographic adapter for letter presses

Info

Publication number: US2341929A
Application number: US408677A
Authority: US
Inventors: William E Lewis
Original assignee: Individual
Current assignee: Individual
Priority date: 1941-08-28
Filing date: 1941-08-28
Publication date: 1944-02-15
Anticipated expiration: 1961-02-15

Description

Feb. 15, 1944. w. E. LEWIS 2,341,929

LITHOGRAPHIC ADAPTER FOR LETTER PRESSES Filed Aug.' 28, 1941 3 Sheets-Sheet 1 Awe/1721 Will/am E. Lew/.5

Feb. 15, 1944. w. E. LEWIS LITHOGR-APHIC ADAPTER FOR LETTER PRESSES Filed Aug. 28, 1941 3 Sheets-Sheet 2 W////'a/77 5 law/5 Feb. 15, 1944. w; LEwls 2,341,929

LITHOGRAPHIC ADAPTER FOR LETTER PRESSES Filed Aug. 28. 1941 3 Sheets-Sheet 5 Z ,8 Z2 4 $5 ,4 4 54 75 a W objects the provision of ing block.

the lithographing Patented Feb. 15, 1944 UNITED STATES PA'TENT' OFFICE LITHOGRAPHIC ADAPTER FOR. LETTER PRESSES William E. Lewis, Portland, Oreg. Application August 28, 1941, Serial No. 408,677 11 Claims. (Cl. 101-130) This invention relates to improvements in printing presses and has for one of its principal an attachment to a letthe same, either permainto a lithographing materpress for converting nently or periodically, chine.

A further object is the provision of an attachment of this character which is of simple, eflicient, durable, and inexpensive construction which may be readily attached to an ordinary letterpress to render the same operable as a lithographic machine, and at less expense than the production of a lithographic machine, as .is now known in the art.

The invention includes a roller to which a lithographic plate may be attached for use as a lithographic machine, and also to which an ordinary inking pad, or cover, may be applied when the machine is used as a letterpress.

The foregoing and other objects will appear as my invention is more fully hereinafter described in the following specification illustrated in the accompanying drawings, a'nd'finally pointed out in the appended claims.

In the drawings:

Figure 1 is a side elevation of a showing my new and improved lithographic attachment operatively applied thereto, and with parts broken away for convenience of illustration.

Figure 2 is a fragmentary sectional detail view of the frame for holding the printing chase, and showing my lithographing printing cylinder and moistening and inking rollersmounted thereon; the printing cylinder being shown as having completed its downward travel over the rubber printing block and ready to be returned to its starting Position in contact with the moistening and inking rollers.

Figure 3 illustrates the assembly shown in Figure 2, after the lithographic cylinder has returned to the moistening and inking rollers following the impression made by the cylinder on the printing block. This view also shows the platen in position to receive the impression from 'the printing block.

Figure 4 is a fragmentary sectional detail view of the lithographing cylinder moving away from the moistening and inking rollers, and dropping into position for traveling over the Figure 5 is an enlarged detail sectional view of cylinder contacting the rubber printing block after leaving its position illustrated letterpress,

rubber printframe 8 and its printing Figure 6 is a fragmentary detail end view showing the lithographing assembly upon reaching its lowermost position with respect to the printing block, and also showing means for holding the lithographing cylinder out of contact with the rubber printing block during the return travel of the assembly. I

Figure 7 is an enlarged detail view partially broken away, showing the lithographing assembly after it leaves the position shown in Figure 6, and is returning to the position shown in Figure 3. Y a

Figure '8 illustrates the lithographing assembly disengaged from a gear-rack for timing the same and in contact with the moistening and inking rollers.

Figure 9 is a slightly reduced and broken front elevation, taken on the line 99 of Figure '7 illustrating the face of the printing block and the lithographing assembly.

Figure 10 is a fragmentary detail plan view, taken on the line Ill-I0 of Figure 3 illustrating the contact between the lithographing assembly and the moistening and inking assembly.

Referring now more particularly to the drawings:

A standard letterpress having such parts as are necessary to illustrate my new and improved lithographic assembly cooperating therewith is illustrated in Figure 1. An ordinary press is indicated by reference numeral I, and has the usual cross shaft 2 journaled therein. The cross shaft 2 is driven by a motor, not here shown, in the usual manner on its one end, and has the fly wheel 3 mounted to its opposite end, as shown. The usual pinion 4 is keyed to. the shaft 2 and drives the large spur gear 5, which is mounted to one end of the shaft 6. The opposite end of the shaft 6 is keyed to the crank wheel 1, the purpose of which will later .be described.

A pivotally mounted frame 8 is mounted to the cross shaft 9, the upper portion of this frame, as indicated at I0, provides the holder for the printing chase IDA (see Figure 3) and is of wellknown practice. A cross'shaft II is journaled within the frame 8, as at l2, outer ends of this shaft is pivotally mounted the connecting rod l3. The opposite end of this connecting rod is joumaled to a crank pin l4, carried by the crank wheel 1. As the crank wheel 1 is rotated, the connecting rod l3 will work the chase toward and away from the main frame I of the press.

A platen I5 is pivotally Journaled within the frame I to the cross shaft l6 and is of well and to the extreme slots 3| of the frames 2|.

journaled to the cross shaft II, which heretofore were used to operate the ink distributing rollers in the operation of the letterpress, and all of the mechanism described above is of the well-known practice used today in letterpresses.

I will now describe the lithographing assembly, which is my invention, as it is applied to the letterpress. A lithographic drum l8, having the usual lithographic sheet l9 applied thereto, by any suitable well-known fastening means, is rotatably mounted to the outer ends 38 of connecting rods 32 as at 28 of the rocker arms H in the following manner.

Side frames 2| are spaced apart and secured together by the spacing bar 22. Trunnion

wheels

23 and 24 are journaled to the side frame 2|, as at 25. These wheels operate over the track 26 of the upper portion In of the frame 8. Pivotally mounted sub-side frames 21 are pivoted, as at 28, to the frames 2|. The lithographic drum I8 is journaled to these subframes within suitable bearings 29, by means of the shaft 3Il. The shaft 38 operates within the A connecting rod 32 is slidably mounted within the side frames l1 at 33 and 34. A compression spring 35 bears against the collar 38, which is fixed to the connecting rod 32, by any suitable means, as a key 31, and pulls the outer end 38 of the connecting rod towards the rocker arms l1. This is of wellknown practice in letterpresses. The outer end 38 of the connecting rod 32 is journaled as at 20 to the outer ends of the shaft 38 of the lithographic drum l8. The compression spring 35 holds the lithographic drum and the frame 2|, whels 23 and 24 against the track 26, and other parts to be described later.

Referring to Figures 3, 8 and 10-the lithographing assembly is in its upper position for receiving moisture and ink thereon from the inking assembly 33, which I will now describe.

The inking assembly illustrated here is of the general type now being used in lithographic machines and no attempt is made to illustrate or describe the details that-are actually required for this inking assembly to operate, but only enough of the details of the assembly are shown to illustrate the principles of combining the inking assembly with a letterpress employing my invention. The ink-trough is illustrated at 48, and the ink is distributed from the roller 4| through the train of inking rollers 42 to the ink distributing roller 43, thence to the lithographic sheet IS on the-lithographic drum l8.

Moisture is delivered from the moisture trough 44 by the roller 45 and train of rollers 43 to the moisture distributing roller 41, thence to the lithogprahic sheet IS. The

rollers

43 and 41 are journaled in the sub-frames 21 at 48, and at 'all times move with the lithographic drum assembly. The ink assembly rollers are driven by the shaft 49, which is geared and driven by the sprocket 58, by any suitable driving assemly at its one end, and having its oppositie end geared to the shaft of the moisture roller 45. A suitable train of gears 52 drive the moisture rollers 43. The inking rollers 42 are driven by the train or gears 53. Suitable gears 54 and S3 transfer the power from the shaft II to the shaft 53, which revolves the ink roller 4| and drives the chain of gears a, which drive the u inking rollers, as heretofore described. This driving assembly operates continuously.

The gears 51, on the

rollers

43 and 41, are driven by the

gears

52 and 53 when the lithographic drum assembly is in the position illustrated in Figures 3, '8 and 10; and thoroughly moisten and ink the lithographic sheet l9.

The operation of the rocker arms I1 is controlled by the connecting link 58, which is pivotaily secured to the arms at 59 at its one end and its opposite end pivotally secured to the oscillating plunger 60 at 6!. The oscillating plunger works within the guide 32 of the frame 83 and straddles the shaft 64 at its lower end 65. A cam wheel 66 is mounted to the shaft 84 and is driven by-the chain 61 through the sprocket 58 mounted to the shaft 9. The stub bearing shaft 64 is fixedly mounted to the frame 83, which is secured to the frame 8 at 88.

I will now describe the operation of this cam relative to the lithographic drum assembly. The arrow line 168 within the cam track 69 is the portion of the cam that will hold the rocker arms l1 in the position shown in Figures 3, 8 and 10, and will hold the arms in this position for a con siderable period of the operating cycle of the machine. Referring to Figure 1, when the cam roller 18 left a position at 11 within the cam track 88, the cam, rotating in the direction indicated, forced the cam roller 10 to the position shown in Figure 1 raising the plunger 68, connecting link 58 bringing the lithographic assembly down to the position shown. Whenthis movement first started, the gears 51 of the lithographic drum assembly were disengaged from the

gears

42 and 46 of the inking assembly, and the gears 12 of the lithographic drum i8 engaged the rack 13, which is secured adjacent the tracks 28 of the frame 8.

Referring to Figure 8, it will be noted that a cam 14 is holding the sub-frame 21 in its outer position so that the gear 12 is disengaged from the rack 13. As soon as the rocker arms I1 are operated by the cam wheel 66, the cam wheel 1! permits the sub-frame 21 to be pulled towards the tracks 26 by the spring 35 cooperating with the rods 32, and after the rocker arms bring the lithographic assembly down to the position shown in Figures 1, 2 and 6, the lithographic drum l8 will be held in timed relation by the gear 12 coacting with the rack 13.

A rubber printing block 18 is mounted within the printing chase lllA instead of the usual type r as commonly used in letterpresses. Referring to Figure 5, it will benoted that the lithographic sheet 19 is contacting the rubber printing block 13 on its downward travel, and is being held in timed relation to the block by the gerr teeth 12 cooperating with the rack 13. It will also be noted that the moistening roller 41 and the inking rolls 43 are being driven by the gear 12 and gear teeth 51 so that a continuous moistening and inking process is taking place. When the rocker arms have reached the lowermost position and are ready to start upward toward the inking position, it is desirable to hold the lithographic drum out of contact with the rubber block on its return travel, this is accomplished in the following manner.

A stop pin 18 adjacent the track 28 engages a lever 13, which is pivotally mounted at I25, with the cam surface of the sub-frame 21 forcinB the lithographic roller to the position shown in Figures 6 and '7. Referring especially to Figure '7, it will be noted that the lithographic sheet selves to others s I9 is spaced away from the rubber block 16, but at the same time the gear teeth 12 are still engaged with the racks 13, holding the lithographic drum in exact timing and at the same time driving the same so that the moistening and inking

rollers

43 and 41 will be revolved, distributing the printing fluid. This is an important feature.

When the lithographic assembly reaches the starting position, as shown in Figures 3, 8 and 10, the cam roller 15, riding up on the cam 14, will raise the sub-frame 21 a sufficient distance to disengage the teeth 12 of the drum 18 to clear th rack 13. This is done simultaneously with roller at its limit of movement away from said rolls.

4. The structure of claim 1, said mounting means for said roller comprising a. roller frame, wheels on said roller frame in constant engagement with said track, means mounting said roller on said roller frame for movement into and out of a block engaging position, said means for elevating said roller comprising a stop on said main the teeth 51 of the

rollers

43 and 41 engaging the

gears

42 and 46 of is so accurately done bly will always be in machine.

After th lithographic assembly has reached its inking position, the machine is so timed that the platen 15, carrying the printing stock, will contact the rubber printing block in the usual type method of operation as illustrated in Figure 3.

A suitable adjustment screw 8| is provided for stopping the sub-frame 21 against the pull of the connecting rods 32, and a spring 82 is mounted around the adjusting screw so that when the lithographic sheet I9 contacts the rubber printing block there will be a slight tension between the connecting rod 32 and the lithographic drum 3 against the rubber printing block.

The cam wheel 66 the inking assembly, and it that the lithographic assemactual timed relation to the minor changes therein will readily suggest themed in the art without departing from the spirit and scope of the invention. Having thus described my invention, what I claim as new and desire to protect by Letters Patent is:

l. A letterpress comprising a main frame, a printing block secured to said frame, a track on either side of said block, separate positively ro tated inking and moistening rolls on said frame, a lithographic roller, means mounting said roller on said tracks for to and fro movement between said rolls and said block, means operative to elea height to clear said block throughout its movement towards said rolls, a rack on said frame operatively connected to said roller to rotate the same throughout its movement in both directions, means on at least one of said rolls engageable with said roller to rotate the same while the latter is being inked an moistened, and means automatically disconnecting said roller from said rack just prior to its engagement with said rotating means of said roll.

2. The structure of claim 1, said last named means comprising a cam on said main frame, and cam actuated means carr'ed by said roller and engageable with said cam.

3. The structure of claim 1, said mounting means for said roller comprising a'roller frame, wheels on said roller frame in constant engagement with said track, means mounting said roller on said roller frame for movement into and out of a block engaging position, said means for elevating said roller'comprising a stop on said main frame, and a lever on said roller frame engageable with said stop and operative to elevate said carried thereby,

ment away from said rolls,

frame, a lever on said roller frame engageable with said stop and operative to elevate said roller at its limit of movement .away from said rolls, said means for automatically disconnecting said roller from said rack comprising a cam on said main frame, and cam actuated means carried by said roller and engageable with said cam.

5. A letterpress, comprising a main frame, a printing block secured to said frame, a track on either side of said block, separate positively rotated inking and moistening rolls carried by said frame, a lithographic roller, a roller frame mounting said roller for to and fro movement on saidtrack between said rolls and said block, means on said main frame for positively rotating said roller throughout its movement in both directions, means automatically disengaging said roller from said last means just prior to its limit of movement towards said rolls, and means on at least one of said rolls engageable with said roller to positively rotate the same while it is being inked and moistened by said rolls.

6. The structure of claim 5, said means for rotating said roller a rack on said frame engageable with said gear, and a gear carried by. said roll and engageable with said roller gear.

'7. A letterpress, comprising a main frame, a printing block secured to said frame, a track on either side of said block, separate positively rotated inking and moistening rolls carried by said frame, a lithographic roller, a sub-frame mounting said roller, a roller frame, said sub-frame being swingably connected to said permit the raising and lowering said roller frame being mounted on said track for to and fro movement between said rolls and said block, means on said main frame for positively rotating said roller throughout its movement in both directions, means on said main frame and engageable with said sub-frame to elevate the same and said roller out of engagement with said roller rotating means just prior to the limit of movement of said roller frame towards said rolls, and means on at least one of moistened by said rolls.

8. The structure of claim 7, said roller being adapted to contact said block during its moveand means operative at the limit of movement of said roller away from said rolls to elevate said sub-frame and roller to a height to clear said block and to maintain said roller so elevated throughout its movement towards said rolls.

9. The structure of claim 7, said sub-frame elevating means comprising a cam on said main frame and a camwheel fixed to said sub-frame and engageable with said cam.

10. The structure of claim "I, said sub-frame elevating means comprising a cam on said main frame and a cam wheel. fixed to said sub-frame and engageable with said cam, a stop main frame in the region of said block, a lever comprising a gear fixedly on said carried by said roller frame, said lever being engageable with said stop and movable thereby to engage said sub-frame and elevate the same and said roller at the limit of movement of said roller frame away from said rolls, saidlever thereafter maintaining said roller elevated to clear said block through the return movement of said roller frame.

11. A letterpress, comprising a main frame, a printing block secured to said frame, a track on either side of said frame, separate positively rotated inking and moistening rollers on said frame, a lithographic roller, means mounting said lithographic roller on said tracks for to and fro movement between said first rollers and said printing block, means operative to elevate said roller to a height to clear said block throvghout its movement towards said first rollers, said mounting means for said lithographic roller comprising a roller frame, wheels on said roller frame in constant engagement with said track, means mounting said lithographic roller on said roller frame for movement into and out of a block en-- gaging position, said means for elevating said lithographic roller comprising a stop on said main frame, and a lever on said roller frame engageable with said stop and operative to raise said lithographic roller at its limit of movement away from said first rollers.

WILLIAM E. LEWIS.