US2108935A - Folding machine - Google Patents

Description

Feb. 22, 1938. w. H. DRAPER FOLDING MACHINE Filed April 24, 1955 5 Sheets-Sheet 1 i, 0 e .M Z: V a

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Feb. 22, 1938. w. H. DRAPER FOLDING MACHINE Fild April '24, 1935 5 Sheets-Sheet 2 @Vewfdf W. H. DRAPER FOLDING MACHINE Feb. 22, 1938.

Filed April 24, 1-955 5 Sheets-Sheet 3 W. H. DRAPER FOLDING MACHINE Feb. 22, 1938.

Filed April 24, 1955 5 Sheets-Sheet 4 Feb. 22, 1938. I v w, H DRAPER 2,108,935

FOLDING MACHINE Filed April 24, 1935 5 Sheets-Sheet 5 Patented Feb. 22, 1938 UNITED STATES PATENT OFFIE Application April 24, 1935, Serial No. 18,062 In Great Britain June 21, 1934 13 Claims.

This invention relates to paper folding machines of the kind in which the sheets to be folded are conveyed to the folding mechanism of the machine by what is generally known as a tape feed. In the known machines of this kind which are provided with a number of folding devices enabling a number of folds to be applied to a sheet in quick succession the rotary speed of the folding rolls, the speed of the tape feed for conveying the unfolded sheet to the first folding device and for registering the sheet relatively thereto and the speed of the tape feeds for conveying the partly folded sheet respectively to the subsequent folding devices are definitely correlated and invariable. The maximum speed at which accurately folded sheets. can be delivered from such a machine or in other words the output of the machine depends largely if not wholly upon the maximum speed at which the feed tapes can feed accurately registered sheets to the first folding rolls and unless the unfolded sheet is accurately registered before the operation thereon of the first folding device faulty folding cannot be avoided.

For this reason in such tape fed multi-folding machines it has been necessary hitherto irrespective of the nature of the paper stock to be folded, to feed the sheets thereof over the initial tape feed to the first folding device at definite intervals in order to provide the requisite clearance between them and enable a sheet in front of another sheet to be properly registered at the usual registering lays before being seized by the fold rolls and the consecutive sheet could take its place without overlapping or fouling. This precaution is essential in any case when sheets of average paper stock are to be folded but with particularly thin stock due to the tendency of thin paper travelling at relatively high speed to bulge or to become buckled on its impact with the lays referred to it has been found that in machines having an invariable speed for all the tape feeds, the folding of thin stock has become most difiicult and impracticable due to the poor output resulting therefrom.

The object of this invention is to provide means adaptable with particular advantage to; such tape-fed multi-folding machines and enabling the above difficulty to be overcome and a maximum output of accurately folded sheets to be ensured irrespective of whether stock of normal thickness or abnormally thin stock such as for example India or Bible paper is to be handled.

To this end according to this invention provision is made of a tape feed which is associated with a change speed device comprising a unit driven from the main drive of the machine for driving the tape feed and the feed supply thereto at a given speed such as the set normal speed of the machine and another unit driven from the main drive and adapted to drive the tape feed at a modified or reduced speed while the other unit continues to drive the feed supply to the tape feed from the main drive at the normal speed of the machine. For the application of this invention to. a folding machine provided as above men? tioned with a plurality of consecutive tape-fed folding devices the use of one common or invariable speed for all the tape feeds throughout the machine is departed from and a variable tape feed according to this invention is substituted for that tape feed in such machinesby which the sheets are conveyed from the feeder or feed table initially into the machine, thus enabling the speed of this initial or first tape feed to be arbitrarily reduced relatively to the normal speed of the other tape feeds or operating speed of the machine. By thus reducing or slowing down the delivery of the sheets to the first fold lay to the lowest possible limit perfectly accurate registration and folding can be assured for sheets of the thinnest paper stock and in addition the sheets can be fed into the machine in close continuity that is to say without any appreciable clearance between them or any risk of bulging or overlapping while maintaining the normal or maximum folding speed throughout the whole of the folding devices. The result therefore is that not only can accurate folding of any stock be safeguarded, but the normal or maximum speed of the machine because of its relative independence of the speed of the initial tape feed can, compared with existing machines, be much higher and the maximum output of the machine can accordingly be likewise increased. The change speed device employed according to this invention in the form of individual units is in this case interposed between the driving gear of the machine and the initial tape feed. The gear units referred to (sprocket wheels being used by preference) are simultaneously driven through individual connections from the main drive and adapted one at .a time to be brought into operative connection with said tape feed while their separate driving connections with the main drive are maintained in operative condition.

A simple constructional form of the invention is illustrated in the accompanying drawings showing its application by way of example to a knife folding machine provided with five knife folding devices.

Fig. 1, la is a lateral elevational view of the machine showing part of the feed table on the left hand side.

Fig. 2, 2a is a plan view clearly indicating the different tape feeds.

Fig. 3 is a front or face View looking from the left of Fig. 1 and 7 Figs. 4 and 5 are right angle detail views of the Variable tape feed according to this invention 7 prising as is known two fold rolls geared together in known manner and suitably driven at the requisite speed and a knife blade time-actuated to force the paper into the bite of the rolls thereby producing a fold.

The sheets are fed to the machine initially by feeder mechanism U consisting of two series of drop-feed rollers V, V, carried by arms secured to a rock-shaft W. The rock-shaft W is moved in timed manner by cam and cam-follower mechanism X so as alternately to lower either the rollers V on to a drum Y or the rollers V on to a drum T. The cam mechanism X is driven through adjustable gearing by the shaft of the drum Y which, in turn, is rotated by a feeder wheel F driven from the main drive of the machine in a'manner hereinafter described.

The feeder mechanism operates by reason of the rocking of the rollers V on to the drum Y, to engage a sheet and move it on to the feed table F and drum T and then, by the reversal of the posi tion of the rollers so that the rollers V are brought into contact with the drum T, to feed the said sheet tothe machine proper.

To the folding stations I and III the sheets are fed from the feed table F by an initial tape feed T composed as usual of a number of parallel tapes in the form of endless conveyors running over appropriately driven rollers. A similar tape feed T is provided to convey sheets from the folding station I to thestation II, a tape feed T to feed sheets from the latter to the folding station IV and a tape feed T to convey sheets from station IV to the folding station V. All the fold rolls at the various knife folding stations are geared and driven in known manner at a uniform speed which for every particular machine of this type is as a rule chosen to be the maximum operating speed of the machine. The folding knives of the knife folding devices are actuated in requisite synchronism through cam gear mechanism'which for the sake of clearness since they are well known in the art have been omitted from the accompanying drawings. The driving connections are only diagrammatically indicated, a belt or chain drive being shown at C for driving the fold rolls of the station I, a chain drive C for driving the rolls of thestation II, a similar drive 0 for driving the fold rolls at folding station III, a drive C for driving the fold rolls at station IV and C for driving the fold rolls at station V. The main driving shaft D receiving its motion from a pulley P is journalled in bearing brackets B mounted on the lower front face portion of the frame A. Through a conical gear train G and a longitudinal stub shaft D driving motion is imparted from the driving shaft D to a secondary driving shaft D from which, as will be seen, the various fold rolls in the stations III, IV and V are driven by the transmissions C C and C already referred to.

It will be observed that the rolls of folding station I driven by the chain drive C derive their motion from the stub shaft D, the fold roll set in each station being equipped with the requisite gear set through which motion is imparted also to the adjacent tape drums, the tape feed T being geared to the folding station III, the tape feed T to the folding station IV and the tape feed T being driven from the folding station V. At the initial feeding point indicated in Fig. 1 by the inner endof the feed table F the tapes of the first tape feed T are laid over the drum T which is mounted on a shaft S journalled in bearing brackets B parallel with the driving shaft D. The drum shaft S is driven from the driving shaft D through a change speed arrangement shown in greater detail in Figures 4 and 5.

Pinned to the shaft D are as shown two sprocket Wheels H and H adapted to drive corresponding sprocket wheels H and H by means respectively of the chains C and C The sprockets H and H are each loosely rotatable on the shaft S which carries the tape drum T forming the driving member in this case of the first tape feed T. Pinned or otherwise secured to the shaft S are flanged sockets L and L. To each of the sprocket wheels 1-1 and H on the shaft S are secured similar flange members L and L respectively with their free faces adjacent to those of the sockets L, L. The sprocket wheel H carries on its opposite face likewise loose on the shaft S a pinion K which during the operation of the machine serves to drive the feeder Wheel F associated with the feeder mechanism. The flange members 'L, L and L, L respectively form members for coupling the sprocket wheels H and H to the shaft S. To this end the members L and L are each provided with a hole M and the flanges on the adjacent members L and L have tappedholes M which can be brought into register with the respective holes M in the flanges L and L. A coupling bolt N screwed into one or the other of the registering pair of holes M, M serves to place one or the other of the sprockets H E into driving connection with the drum shaft S. It will be noted that the sprocket wheels on the two shafts D and S have respectively different diameters and as the ratio between the diameter of the sprockets H, H is different from that between the sprockets H, IF, it will be apparent that different speeds will be imparted to the tape drum T from the shaft S according to whether the drive H, 0 H or the drive H, C H is taken into use. In other words the rotary speed of the tape drum T through the shaft S may be varied relatively to that of the driving shaft D by coupling either the sprocket H or the sprocket 1-1 to the drum shaft S as may be required and accordingly the feed speed of the initial tape feed T may be independently varied in relation to that of the remaining tape feeds and other devices which de rive their uniform maximum working speed from the driving shaft D through the connections hereinbefore already explained. This maximum speed is imparted from the driving shaft D to the drum shaft S by causing the drive to the shaft S to be transmittedthrough the chain drive H, C H ,'in which case the tape feed T driven by the tape drum T will travel at the same speed as all the other tape feeds. When however driving motion from the shaft D is imparted to the drum shaft S through the chain gear H, C, 1-1 the tape feed T will travel at a reduced speed relatively to that of the other tape feeds. It will be observed that the change from one speed to the other of the tape drum T by coupling either the sprocket wheel H or sprocket wheel H to the drum shaft S may be effected by this arrangement while both these sprocket units remain in driving connection with the respective sprocket wheels H, H on the driving shaft D in that while the sprocket unit H is coupled to the shaft S for driving the latter from the driving shaft D at reduced speed through its chain connection C the sprocket wheel I-I turning loosely on shaft S is simulaneously driven by its connection C from the driving shaft D thus continuing to drive the feeder wheel F through the pinion K secured to it for that purpose. Then if the sprocket H is coupled to the shaft S to impart to the initial tape feed T the higher or normal operating speed of the machine the sprocket H now uncoupled continues to turn loose on its shaft. li'c disruption therefore of the driving connection C or C is necessary. In the drawings R indicates the usual stops or lays against which a sheet is advanced by the corresponding tape feed for proper registration before or just as the knife is operated to force the paper down into the bite of the respective fold rolls to make a fold. For right angle or cross folding the fold station I and thereafter any one or more of the consecutive folding devices II, IV and V may be used. For parallel folding the fold stations I and II are not used and if therefore sheets are to receive parallel folds only as is customary particularly in the case of India or Bible paper the folding devices I and II are cut out in the well known manner by disconnecting and thereby arresting their folding blades.

In the operation of the machine when ordinary paper stock is to be cross folded at normal operating speed of the machine the sheets fed from the feeder U in travelling over the first tape feed T to the first folding station I are as usual spaced apart sufficiently to prevent overlapping. The normal drive connection H H is used for driving also the initial tape feed T by locking the sprocket H including the gear wheel K to the drum shaft S. A first fold will be given to the sheet in station I whence it drops from the fold rolls of that station on to the tape feed T to be conveyed at right angles to station II to receive a fold at right angles to the first fold whereafter it is carried over the tape feed T to the folding station IV to be given a third fold parallel to the second fold and then over the tape feed T to the last folding station V where it receives a last or fourth fold again parallel to the preceding fold. For parallel folding only or when thin paper is to be dealt with the folding stations I and II are as already stated rendered inoperative and the first front lays R are withdrawn so as to provide for a free passage of the paper over the initial tape feed T to the first operative folding device which is now at station III. The coupling bolt N is withdrawn from the fiange members L, L and inserted in the coupling holes M, M of the flange members L and L thereby establishing driving connection through the chain drive H (3 and H, the sprocket H and pinion K being thus disconnected from the tape drum shaft S but continue to be driven independently thereof direct from the driving shaft D. The drive of the tape feed T is thus now effected through the sprockets H and 1-1 at the requisite reduced speed while the feeder F is still driven at the normal rate by way of the gear K which is in driving connection with the sprocket H As a result of this the feeder wheel delivers sheets as rapidly as before while the tape feed T is moving, however, more slowly. Consequently the sheets so fed are carried slowly but in close continuity direct to folding station III where after accurate registration at the lays and without risk of overlapping or buckling they are quickly seized and folded at the unreduced folding speed of the machine. Here after receiving one fold they are either delivered or if required caused to pass through folding stations IV and V over the tape feeds T and T respectively. Having been folded once they are smaller and thicker and therefore no longer apt to give trouble in travelling over the normally driven tape feeds 'I and T to the registering stops at these stations. It will be appreciated therefore that by the embodiment of the invention as hereinbefore explained the same compound folding machine is capable of performing the work of two separate machines hitherto customarily employed inasmuch as it can be used equally well for thin and thick paper stock and can be built at the outset for running at a relatively higher normal operating speed than was hitherto possible with the resulting additional advantage of a correspondingly increased output of accurately folded sheets.

It will be appreciated by those skilled in the art that a variable tape feed as herein explained constitutes substantially a self-contained unit for attachment capable of being applied to or embodied in a folding machine irrespective of whether the latter is provided only with one or with a plurality of consecutive folding devices and moreover that the specific embodiment of the invention as herein described may be readily adapted for use with any particular machine or varied constructionally also by the use of other equivalent speed gear types.

I claim:

1. In a folding machine of the character described, a feeder, at least one folding device, a tape feed for conveying paper sheets from said feeder to the folding device, a tape feed driving shaft, a main drive shaft in timed driving connection with said folding device, a unit on said tape feed driving shaft, means for driving said unit at one speed from said main drive shaft, a second unit on said tape feed driving shaft, means for driving said second unit at a different speed from said main drive shaft, means for driving said feeder from said second unit, and means for selectively coupling said units to said tape fee-d driving shaft.

2. A folding machine of the character described, comprising at least one folding device, a feeder, a plurality of conveyor tapes for conveying paper sheets from said feeder to said folding device, a tape carrying and driving drum, a shaft carrying and driving said drum, a unit loosely mounted on said shaft, a main drive in timed connection with said folding device, means for transmitting motion from said main drive to said unit to cause the unit to rotate at one speed, a second unit loosely mounted on said shaft, means for transmitting motion from said main drive to said second unit to cause the second unit to rotate at a different speed, means for transmitting motion from said second unit to said feeder, and means for selectively coupling said units to said shaft to cause said shaft to rotate at the speed of one of said units.

3. A folding machine of the character described, comprising a plurality of conveyor tapes, a tape carrying and driving drum, a shaft carrying and driving said drum, a feeder for supplying sheets to said tapes, a unit loosely mounted on said shaft, a main drive, means for transmitting motion from said main drive to said unit to cause the unit to rotate at one speed, a second unit loosely mounted on said shaft, means for transmitting motion from said main drive to said second unit to cause the second unit to rotate at a different speed, means for transmitting motion from said second unit to said feeder, a coupling element carried by each unit, a coupling element associate-d With each unit and fixed to said shaft, and means for selectively rendering said coupling elements operative.

4. A folding machine of the character described, comprising a plurality of conveyor tapes, a tape carrying and driving drum, a shaft carrying and driving said drum, a feeder for supplying sheets to said tapes, a unit loosely mounted on said shaft, a main drive, means for transmitting motion from said main drive to said unit to cause the unit to rotate at one speed, a second unit loosely mounted on said shaft, means'for transmitting motion from said main drive to said second unit to cause the second unit to rotate at a different speed, means for transmitting motion from said second unit to said feeder, a coupling element carried by each unit, a coupling element associated with each unit and fixed to said shaft, the coupling element carried by one unit and the associated element fixed to the shaft having bores therein adapted to register, the coupling element carried by the other unit and its associate having similarregistering bores, and means adapted to enter the bore of the coupling elements of a selected unit to connect said unit to the shaft and impart rotation thereto.

5. In a tape-fed paper folding machine, the combination of a main drive, two folding devices each a-dapted to be operated at the same speed in timed manner from said main drive, a feeder likewise driven from said main drive, a single tape feed for conveying paper sheets from said feeder to either of said folding devices, and change speed means for driving said tape feed from'said main drive at one of two predetermined speeds correlated respectively with each 7 of the two folding devices.

6. In a tape-fed paper folding machine having a main drive, at least two folding devices adapted to be operated at the same speed in timed manner from said main drive and a feeder, the combination of a singletape feed for, conveying paper sheets from said feeder to'either of said two folding devices and a change speed device comprising a unit driven from the main drive 'for driving said feeder at the same operative speed as said folding devices and for driving said tape feed at a speed correlated tonne of said folding devices, and a unit driven from said main drive and adapted to drive said tape feed, at a modified speed correlated to the other of said folding devices while the other unit continues to drive said feeder from the main drive at said given speed;

'7. In ,a tape-fed paper folding machine provided with a driving shaft, a plurality of consecutive tape feeds, two folding devices each associated with one of said tape feeds and adapted to be operated at a common folding speed by said driving shaft but requiring different speeds of sheet feeding thereto, the combination with said single tape feed of a change speed device for driving said tape feed at either of two predetermined speeds suitable to the requisite sheet feed ing speeds of the two respective folding devices.

8. In a tape-fed paperfolding machine according to claim 7, in which the change speed device comprises tWo gear wheels driven simultaneously and individually from said driving shaft, each of said gear wheels being adapted to establish driving connection between said tape feed and said driving shaft independently of the other while the driving connections of both with said driving shaft are maintained.

. 9. In a tape-fed paper folding machine having a driving shaft, a tape feed, two folding devices each associated with said tape feed and adapted to be operated at a common operative folding speed but requiring different speeds of sheet feeding thereto, and a shaft for actuating said tape feed, the combination with said tape feed of two wheels associated with the shaft of said tape feed, said wheels being each loosely rotatable on said shaft and adapted to be coupled individually and selectively thereto for driving said shaft at one of the two speeds required by one of said folding devices, while being simultaneously driven through individual driving connections from said driving shaft. 7

10. In a tape-fed paper folding machine having a driving shaft, a tape feed, two folding devices each requiring a different speed of sheet feeding thereto and associated with said tape feed, and a shaft for actuating said tape feed, the combination with said tape feed of two gear wheels loosely rotatable on the shaft for actuating the tape feed and in different ratio driving connection with said drivinglshaft, a coupling member mounted on said shaft in association with each of said gear wheels, and means adapted to establish operative connection respectively between each of said gear wheels and said shaft through its associated coupling member independently of the other for driving said tape feed at one of the two speeds correlated respectively with each of said folding devices.

11. Ina tape-fed paper folding machine having a tape feed, a feeder for supplying paper sheets to said tape feed, a knife folding device associated with said tape feed and arranged to produce folds parallel with the direction of said tape feed, a second knife folding device associated with said tape feed and arranged to pro duce folds at right angles to the direction of said tape feed, and a main drive in timed driving connection with each of said folding devices, the combination with said tape feed of a change speed device comprising a high speed wheel unit and a low speed wheel unit simultaneously and individually driven from the main drive and adapted to be selectively connected to said tape feed for driving said tape feed at a highspeed for use with the first knife folding device and at a predetermined reduced speed for usewith the second knife folding device, and an auxiliary gear wheel associated with said high speed wheel unit for continuously driving said feeder from said main drive irrespective of the speed imparted to -said tape feed from the low speed wheel'unit.

12. In altape-fedpaper folding machine provided with a plurality of consecutive tape feeds, two knife folding devices associated with the first of said tape feeds, a feeder for supplying paper sheets to said first tape feed, and a driving shaft in timed driving connection with each of said folding devices, the combination with said first tape feedof a change speed device comprising separate high and low speed units simultaneously driven through individual driving connections from said driving shaft and adapted to actuate said first tape feed at high and reduced speeds correlated respectively with each of said knife folding devices associated with said tape feed, and an auxiliary gear wheel associated with said high speed unit for continually driving said feeder at a constant speed with respect to said driving shaft and said folding device irrespective of the speed simultaneously imparted to said first tape feed through the low speed unit.

13. In a tape-fed paper folding machine having a tape feed, two knife folding devices arranged to produce folds at right angles to one another associated with said tape feed, a drive for said tape feed and a driving shaft, the combination with said tape feed drive of two separate change speed units in the form of sprockets associated with said tape feed drive each connected and continually driven respectively from corresponding units secured to the driving shaft, and means for selectively coupling one of said change speed units to said tape feed drive to effect the driving of said tape feed drive at one of two speeds correlated respectively with each of said knife folding devices.

WILLIAM HORACE DRAPER.

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