US2183128A

US2183128A - Sheet feeding apparatus

Info

Publication number: US2183128A
Application number: US217199A
Authority: US
Inventors: Baker Leonard
Original assignee: Dexter Folder Co
Current assignee: Dexter Folder Co
Priority date: 1938-07-02
Filing date: 1938-07-02
Publication date: 1939-12-12
Anticipated expiration: 1956-12-12

Description

Dec. 12, 1939. L. BAKER 2,183,121;`

SHEET FEEDVING' APPARATUS Filed July 2, 1938 s sheets-sheet 1' y INVENTOR LEONARD BAKER ATTORNEY SHEET FEEDING APPARATUS Filed July 2, 1938 l3 Sheets-Sheet 2 (4o 4 939 lNvENToR' G LEONARD BAKER ATTORNEY 4 Dec. l2, 1939'. BAKER 2,183,128

SHEET FEEDING APPARATUS Filed July 2f, 1938 v 3 Sheets-Sheet 3 Q IM `84 naf- "45j s INVENTOR LEONARD BAISER ATTORNEY Patented Dec. 12, 1939 UNITED STATES SHEET FEEDING APPARATUS Leonard Baker, Hillsdale, N. '.I., assignor to Dexter Folder Company, New York, N. Y., a corporation of New York Application July 2, 1938, Serial No. 217,199

14 claims.

'I'his invention relates to sheet feeders and more particularlyto pile elevators and mechanism for operating the same.

One object of the present invention is to provide a sheet feeder having novel and improved mechanism for imparting either intermittent or continuous motion, as desired, to a pile elevator of said feeder.

Another object of the present invention is to provide a sheet feeder wherein intermittent or continuous movementk of its pile elevator and control of such movements may be eectively and conveniently obtained through the provision of a single, unitary mechanism.

Another object of the present invention is to provide a sheet feeder' wherein the sheet feeding elements and usual driving means therefor are relieved from the strain of' operation of the sheet supply moving means through the provision of separate and unitary operating mechanism therefor.

Another object of the present invention is to provide a sheet feeder wherein intermittent upward movement of its pile elevator, as well as Acontinuous and rapid up and down movement thereof, may be obtained from a'single selective gear transmission through the provision therein of a pawl and ratchet mechanism operated by certain gears thereof.

Another object of the present invention is to provide, generally, a selective gear transmission unit by which intermittent motion, as well as continuous motion, may be imparted to a part of a sheet feeder or any other machine or instrumentality.

These and other objects of the present invention, will appear as the following description 4thereof proceeds and in order to more clearly understand said invention reference may be had to the accompanying drawings which illustrate one embodiment of said invention.

In said drawings:

Fig. l is a side elevation of a sheet feeder embodying the present invention; y

Fig. 2 is a front elevation of the sheet feeder shownin Fig. l; l

Fig. 3 is an enlarged fragmentary top plan view, partly in section, of the pile elevator operating mechanism and control means therefor i@ shown in Figs. l and 2;V

Fig. 4 is an enlarged fragmentary rear eleyvation of the pile elevator operating mechanism shown in Fig. 3;

Fig. 5 is an enlarged fragmentary side view, partly'in section, of the mechanism` shown in Figs. 3 and 4 looking from the left thereof and illustrating in inoperative positionv a pawl and ratchet device and control means therefor form,- ing part of said mechanism;

Fig. 6 is an enlargedvertical transversesectional view on the line 6-6 of Fig. 4;

Fig. 'l is a view similar to Fig. 5 showing the pawl and ratchet mechanism and control means therefor in operative position; and

Fig. 8 is an enlarged fragmentary rear elevation of the pawl and ratchet mechanism, showing means for disconnecting said mechanism from the pile elevator when it is continuously and rapidly raised or lowered.

Referring to the drawings wherein like reference characters designate like parts throughout the severalviews, the present invention is shown as embodied in a sheet feeder having a frame comprised by front heads 5 and rear heads 6 connected together by side members 1.

The front and

rear heads

5, 6 are secured to,

of this j ack shaft I2 is journalled in a suitable bearing provided by a bracket I3 that is bolted or otherwise suitably secured on one of the front heads 5. Fixed onthe upper end of jack shaft I2 is a bevel gear I4 which meshes wth'a similar gear I5 fixed on a short shaft.I6 journalled in suitable bearings inthe bracket I3 and the adjacent front head 5. Fixed on the short shaft The main and usual drive for the 2 I6 is al spur pinion I1 which meshes with a spur gear -I8 that is fixed ona cam shaft I9. yThis cam shaft I9 is journalled in suitable bearings in 'the front heads 5 and is utilized to operate the sheetseparating,v forwarding and conveying devices (not shown) -of the feeder.

The sheet feeder includes a pilevelevator comprising cross beams 20 adapted to support a pile board 2|' and pile of sheets 22 thereon. The cross beams 20 engage. over side members 23 connected, as by.couplings 24, with chains 25 the links of which engage over teeth of sheaves 26 fixed on and'rotated by shafts 2l. Shafts 21 extend longitudinally of -the feeder frame and are journalled in suitable bearings in brackets 28 and 29 which are bolted or otherwise suitably secured to the front heads 5 and side members 7,'respectively. Fixed on shafts 21 are right and left hand worm gears 30 and 3| that mesh with right and left hand worms 32 and 33 fixed on a shaft 34 which is driven in a manner hereinafter described to operate the pile elevator. Shaft 34 extends transversely of the feeder frame and is journalled in suitable bearings in the brackets The sheets are separated and forwarded one after another from the top of the pile by separating and forwardly devices of the suction type (not shown) which are suitably connected with the vacuum side of a pump 35. Preliminary to the separating and forwarding of sheets from the top of the pile, the upper portion of the pile and each sheet separated therefromis winded by winding devices (not shown) which are suitably connected with the air side of pump 35. These devices form no part of the `present invention and it is therefore unnecessary to illustrate and describe the same in detail. Pump 35 is bolted or otherwise suitably secured to a pair of cross rails 36 which are bolted or otherwise suitably secured at opposite sides of the feeder frame to brackets 31 carried by the front upright posts or standards 8 and resting on the brackets I0.

In accordance with one aspect of the present invention, the feeder is provided with novel and improved mechanism for intermittently raising the pile elevator and pile of sheets 22 thereon to maintain the top of the pile in proper feeding position, and for continuously and rapidly lowering and raising the pile elevator to load or reload it. This mechanism is preferably mounted, constructed and operated as follows. Bolted or otherwise suitably secured to the cross rails 36 at one side of pump 35 is a housing indicated broadly at 38 (Figs. l to 4 inclusive) and comprised by an inner shell 39, an end plate 4|, an intermediate plate 40, and a cover 51 all bolted together in any suitable manner. Bolted or otherwise suitably -secured to the plates 40, 4| of housing 38 at the tops thereof is an electric motor 42 (Figs. 1 and 2) connected with a suitable source of current and controlled for starting and stopping purposes 'by suitable switch means (not shown).

Fixed on the armature shaft 43 of motor 42 is a sprocket 44 around which passes a chain 45 that also passes around a sprocket 46. This sprocket 46 and a part 41 of a clutch indicated broadly at 48 (Figs. 3 and 4) are secured to or formed integrally with each other and loosely mounted on a short driving shaft 49 which extends through the housing 38 and is journalled in suitable bearings in the plates and 4| thereof. The clutch 48 is of well known construction needing no detail description herein and includes another part 50 which is xed on the driving shaft 49. The parts of the clutch 48 may be connected and disconnected by a device 5| (Fig. 3) loosely and slidably mounted on the driving shaft 49 and provided with a collar 52 in the groove of which extends an operating fork 53. This fork 53 is xed on one end of a shaft 54 which is slidably mounted in suitable bearings ina bracket 55 bolted or otherwise suitably secured to plate 4| and in a lug 56 formed on the cover 51. Cover 51 of housing 38 encloses a pawl and ratchet mechanism hereinafter described for intermittently raising the elevator. Pivotally connected with the opposite Vend of shaft 54 is one end of a link 58 (Figs. 3, 4 and 5) the opposite end of which is pivotally connected with a lever 59 that is pivotally mounted on a stud 60 secured in a lug 6| formed on the cover 51. It will thus appear that

vthe clutch parts

41 and 50 may be connected and disconnected through movement of the lever 59 in opposite directions and thus connect and disconnect the motor 42 relative to the driving shaft 49.

The driving shaft 49 is provided longitudinally thereof with a key 62 (Figs. 3 and 4) between the plates 40 and 4| of housing 38. Fixed on and slidable along the driving shaft 49 and key 62 is a spur gear 63 which, when in the full line position shown in Figs. 3'and 4, meshes with a similar gear 64 that is keyed or otherwise suitably secured on an intermediate shaft 65 (Figs. 3, -4 and 6) adjacent the plate 4| of housing 38. Shaft 65 is journalled in suitable bearings in the plates 48 and 4| of housing 38 and is connected, as by a flexible coupling 66, with the shaft 61 of pump 35 to drive the latter. Keyed or otherwise suitably secured to the intermediate shaft 65 adjacent the plate 40 is a spur pinion 68 which meshes with a spur gear 69 that is loosely mounted on the driving shaft 49. This spur gear 69 is provided with a long hub 10 (Fig. 3) which extends through the plate 48 of housing 38 into the cover 51 thereof.

Clamped or otherwise suitably secured to the outer end of hub 10 is a crank disk 1| (Figs. 3, 4 and 5) the crank pin 1| of which is pivotally connected with one end of 4a link 12 the opposite end of which is pivotally connected with the pin 12 of a pawl carrier 13 that is loosely mounted on a driven shaft 14'. This driven shaft 14 extends through the housing 38 and is journalled in suitable bearings in the plates 4D and 4| thereof. Fixed on the outer end of driven shaft 14 is a bevel gear 15 which meshes with a similar gear 16 that is xed on one end of a vertically extending inclined jack shaft 11 (Figs. l and 2). Jack shaft 11 is journalled in suitable bearings in brackets 18 and 19 which are bolted or otherwise suitably secured to one of the brackets 31 and to one of the front heads 5, respectively. Bracket 18 also provides an additional bearing for the extended end of shaft 14. Fixed on the upper end of jack shaft 11 is a bevel gear 80 which meshes with a similar gear 8| that is fixed on the worm shaft 34. It will thus appear that movement of the pile elevator is imparted thereto by the jack shaft 11 through the described connections therefor with the driven shaft 14 and the worm shaft 34.

The driven shaft 14 may be rotated intermittently in the proper direction to impart step by step upward movement to the pile elevator and pile of sheets 22 thereon, and this intermittent rotation of shaft 14 is preferably effected and controlled by mechanism of the general type disclosed in the application Serial No. 116,692 of Leonard Baker, George A. Martin and Leo C. Williams, led December 19, 1936. This mechanism includes the pawl carrier 13 (Figs. 3, 4 and 5) which has a pawl 82 pivoted thereon and normally resting on a pawl mask 83 out of engagement with a ratchet 84 that is xed on the driven shaft 14. The pawl mask 83 is loosely mounted on shaft 14 adjacent the ratchet 84 and yieldably 'connected with the pawl carrier 13.

Stopping of the pawl mask 83 to permit pawl 82 to engage and drive the ratchet 84 is effected by an overbalanced latch 85 (Figs. 3 and 5) which is pivoted as at 86 on the cover 51 above a plunger 81 that is slidably mounted in a housing 88 formedintegrally with said cover. Co'nnected with the housing 88 at the bottom thereof t' strain of intermittently 'raising the elevator dur- 2,188,128 is one end of a. flexible conduit 89 the opposite end of which is connected with a housing 90 (Figs. 1 and 2) which has slidably mounted therein a detector 9| that rests by gravity on the top of the pile 22 at the rear thereof. Housing 90 is bolted or otherwise suitably secured to a cross bar 92 which, in turn, is bolted or otherwise suitably secured to brackets 93 that are .adjustably secured on side bars 94 supported in brackets 95 bolted or otherwise suitably secured to the side members 1 of the feeder frame. Connected with the housing 90 is one end of a flexible conduit 96 which is suitably connected with the air side of pump to supply air under pressure in said housing.

When the top of the pile of sheets 22 is at the proper height, no compressed air will be delivered in the housing 88 and the latch 85 will be held in the position shown in Fig. 5 above the path of travel of mask 83 so that the latter andthe carrier 13 for pawl 82 will oscillate idly. When the top of the pile 22 and detector 9| lower sumciently so that said detector admits compressed air in the conduit 89 and the housing 88, said air will raise the plunger 81 and swing theflatch 85 to the position shown in Fig. 7 into engagement with the pawl mask 83 to stop rotation of the same and enable the pawl 82 to engage and drive the ratchet 84 and shaft 14 to raise theI elevator and the pile of sheets.

When the top ofthe pile has reached the proper height the detector 9| will cut off the supply of compressed air to conduit 89 and housing 88 whereupon the plunger 81 will drop by gravity in the housing and the latch,85 will be swung to its inoperative position. The carrier 13, the pawl 82 thereon, and the mask 83 will then oscillate idly until it is again necessary to elevate-the pile 22, whereupon the above described operations of the pawl and ratchet control means are repeated so that shaft 14 may be actuated to raise the elevator. It will thus appear that through oscillation of the pawl carrier 13 by the `described driving connections therefor with motor 42, and through engagement of the oscillating pawl 82 with the ratchet 84, the driven shaft 14 will be intermittently rotated and thus rotate worm shaft 34 through the described driving connections therefor with said shaft and raise the elevator and pile of sheets thereon. It will further appear that during normal operation of the feeder, the pump 35 and pawl carrier 13 through the described driving connections therefor with motor 42 will be continuously driven to create vacuum in the sheet separating and forwarding devices, supply air under pressure to the pile and sheet winding devices, and actuate the pile elevator under the control of the detector 9|.

It will further appear that in accordance with another aspect of the present invention, the pawl and ratchet mechanism is driven, as by the motor 42, from a source of power independent of the source of power for driving the means that imparts motion to the sheet feeding elements of the feeder and that in this manner the severe ing the normal operation of the feeder, is eliminated from the motion imparting means for the sheet feeding elements with resulting longer life 'and vless wear of the various'parts constituting Moreover, location of the pawl and the same; ratchet mechanism and driving means therefor at a point remote from the line of sheet travel results in less spoilage of sheets due to oil dripy ping from said lmechanism and driving means.

When it is desired to reload the pile elevator, or to initially load it, said elevator may be rapidly lowered to a position to receive a pile of sheets which-"is placed thereon through the rear of the feeder. In accordance with the present invention this rapid lowering of the pile elevator is preferably effected as follows. The

clutch parts

41 and 50 of clutch 48 are disconnected by moving lever 59 to'the right (Fig. 4) thereby disconnecting the motor 42 from the driving shaft 49. At this time gear 63 on shaft 49 is disengaged from gear 64 and moved along said shaft into mesh with a spur gear 91 as shown in dotted line posisition in Fig. 4. This spur gear 91 is loosely mounted on the intermediate shaft 65 and meshes with a similar gear 98 that is keyed or otherwise suitably secured to the driven shaft 14.a Longitudinal displacement of spur'gear 91 on shaft 65 is prevented by a spacing collar 99 thereon` It will thus appear that when the parts of the clutch 48 are again engaged by moving lever 59 to the left (Fig. 4), the driven shaft 14 will be rapidly and continuously rotated in the proper direction by the motor 42 through

gears

63, 91 and 98 thereby rapidly lowering the elevator to the proper position for loading. At this time the parts of the clutch 48 are disengaged by moving lever 59 to the right (Fig. 4) and the elevator is stopped. It will further appear that when the elevator is rapidly lowered as pointed out above, the intermediate shaft 65, through disengagement of gear 63 from gear 64, will be disconnected from the motor 42 thereby stopping the pump 35, crank disk 1| and pawl carrier 13.

Shifting of the gear 63 along driving shaft 49 is accomplished by a fork |00 (Figs. 3 and 4) which engages opposite sides of said gear and is bolted or yotherwise suitably secured to a shaft |0I. This shaft |0| extends through the housing 38 and is slidably mounted in suitable bearings in the plates 40 and 4| thereof. Pivotally connected with one end of shaft |0| is one end of a link |82 which extends through a suitable opening in the cover 51. yThe opposite end of link |02 is pivotally connected with a shift lever |03 that is pivotally mounted on the stud 60 adjacent the lever 59. The slidable shaft |0| has Yalso fixed thereon a block |04 (Figs. 3, 4 and 8) forms a cam track |06 engaged by a roller |01.

Roller |01 is journalled on one arm |08 of a double armed lever |09 which is pivotally mounted on a pin ||0 secured in the cover 51. Endwise displacement of lever |09 on pin ||0 is prevented by collars secured to said pin on opposite sides of said lever. The other arm ||2 of lever |09 has loosely mounted therein at the lower end thereof a block ||3 engaging in a groove ||4 of the pawl mask 83 which is slidably as well as rotatably mounted on the driven shaft 14. It will thus appear that when the shift lever |03 and shaft |0| are moved to the left (Fig. 4) to move gear 63 along shaft 49 into mesh with gear 91, the arm ||2 of lever |09 and pawl mask 83 are at the same time moved to the right so that a bevelled annular ange I|5 on the mask will lift the pawl 82 out of engagement with the ratchet 84 Yas'indicated in Fig. 8 of the drawings if said pawl sheet feeding operation. For this purpose, further movement of the shift lever ID3 to the left (Fig. 4) disengages gear 63 from gear 97 and moves a spur pinion l I6 along shaft 49 to the dotted line position indicated in Fig. 4 of the drawings. In this position of pinion H6 it meshes with a large spur 'gear Ill that is also keyed or otherwise suitably secured to the driven shaft 'M The spur pinion H6 is secured to or formed integrally with the gear 63 and is slidable therewith along the driving shaft 49. It will thus appear that when the parts of the clutch i8 which have ben previously disengaged, are again engaged by` moving lever 59 to the left (Fig. 4), the shaft M will be rapidly and continuously rotated in the opposite direction by the motor (i2 through pinion H6 and gear Ill and thus rapidly raise the elevator and the pile of sheets thereon until the top of the pile reaches the proper level for feeding of the sheets one after another therefrom.

At this time the lever 59 is again moved to the right (Fig. 4) to disconnect the parts of the clutch i8 and stop the elevator. Shift lever |03 is then also moved to the right (Fig. 4) to its full line .position thus disengaging pinion H6 from gear Hl and again engaging gear 63 with gear 6G to drive the pump 35, crank disk Il and pawl Carrier 73. When the shift lever lis moved as aforesaid, the pawl mask 83 is moved back again to its normal position by the cam track H16 on shaft ll.

Feeding of sheets from the top of the pile may now be begun or resumed by moving lever Fifi to the left (Fig. 4) thereby connecting the clutch parts of the clutch i8 and the motor (l2 with the driving shaft (i9, and starting the feeder which during the loading or reloading operations may be stopped to eliminate unnecessary wear of the various parts f the feeder during such operations. It is to be noted, that should the rapid raising of the elevator and pile of sheets thereon be stopped before the top of the pile has reached the proper feeding level, the pawl and ratchet mechanism will immediately begin to operate as soon as gear G3 is moved into mesh with gear (ifi and the clutch parts of clutch [i8 are connected to drive the pump 35 and the pawl carrier 13. In this way, and before the feeder is started for normal operation thereof, the elevator and pile of sheets may be rapidly raised to within a certain distance of the proper feeding level and thereafter intermittently raised and automatically stopped when the proper level is reached. This eliminates any absolute requirement for attention on the part of the machine attendant when raising the pile to the proper feeding level. Locating and locking of the gear 63 and the pinion' I i6 in each of their positions along the driving shaft i9 is accomplished by a spring pressed ball H8 (Fig. 4) carried in the plate lli] of housing 38, and engaging in depressions or sockets H9 formed in and suitably spaced along the shaft I Ul.

While one embodiment of the present invention is herein illustrated and described With more or less particularity, it is to be expressly understood that said invention is not limited to said embodiment or to the specific type of equipment disclosed or otherwise than by the terms of the appended claims.

What I claim is:

1. In a sheet feeder, a pile elevator, a housing, a driving shaft in the housing, a gear loose on the driving. shaft and rotatable independently thereof, a driven shaft in the housing and connected with the pile elevator, a pawl and ratchet mechanism on the driven shaft, means for connecting the pawl and ratchet mechanism with and operating it from the loose gear on the driving shaft, an intermediate shaft in the housing and connected with the loose gear on the driving shaft, and means for driving the intermediate shaft from the driving shaft, whereby said driven shaft may be rotated intermittently in one direction by said loose gear and said pawl and ratchet mechanism to intermittently raise the pile elevator.

2. In a sheet feeder, a pile elevator,'a housing, a driving shaft in the housing, a gear loose on the driving shaft and rotatable independently thereof, a driven shaft in the housing and connected with the pile elevator, a ratchet fixed on the" driven shaft, a pawl and a carrier therefor pivotally mounted adjacent the ratchet, a crank fixed on the loose gear and connected with pawl carrier to oscillate the same, an intermediate shaft in the housing and connected with the loose gear on the driving shaft, and means for driving the intermediate shaft from the driving shaft, whereby said driven shaft may be rotated intermittently in -one direction by said loose gear, the pawl n said carrier, and said ratchet to intermittently raise the pile elevator.

3. In a sheet feeder, a pile elevator, a housing, a driving shaft in the housing, a gear loose on the driving shaft and rotatable independently thereof, a driven lshaft in the housing and connected with the pile elevator, a pawl and ratchet mechanism on the driven shaft, means for connecting the pawl and ratchet mechanism with and operating it from the loose gear on the driving shaft, an intermediate shaft in the housing and connected with the loose gear on the driving shaft, means for driving the intermediate shaft from the driving shaft, whereby said driven shaft may be rotated intermittently in one direction by said loose gear and said pawl and ratchet mechanism to intermittently raise the pile elevator, and pile controlled meanson the housing controlling the operation of the pawl and ratchet mechanism.

4. In a sheet feeder, a pile elevator, a housing,

' a driving shaft in the housing, a gear loose on the driving shaft and rotatable independently thereof, a driven shaft in the housing and connected with the pile elevator, a pair of gears fixed on the driven shaft in spaced relation, an intermediate shaft in the housing having a pair of gears fixed thereon in spaced relation and an intermediate loose gear continuously meshing with one of the gears on the driven shaft, a pawl and ratchet mechanism' on the driven shaft, means for connecting the pawl and ratchet mechanism with and operating it from the loose gear on the driving shaft, and means for selectively driving a fixed or the loose gear on the intermediate shaft from said driving shaft, whereby said driven shaft may be rotated intermittently in one direction to raise the pile elevator or continuously in the opposite direction to lower said pile elevator.

5. In a sheet feeder,'a pile elevator, a housing, a driving shaft in the housing, a gear loose on the driving shaft and rotatable independently thereof, a driven shaft in the housing and connected with the pile elevator, a pair of gears fixed on the driven shaft in spaced relation, an intermediate shaft in the housing having a pair of gears fixed thereon in spaced relation and an intermediate loose gearcontinuously meshing `vwith qne of the gears on the driven shaft, a pawl and ratchet mechanism on the driven shaft, means for connecting the pawl and ratchet mechanism with and operating it from the loose gear on the driving shaft, and means for selectively driving a xed gear on the intermediate shaft or a fixed gear on the driven shaft from the driving shaft, whereby said driven shaft may be rotated intermittently or continuously in the same direction to raise the pile elevator. l

6. In a sheet feeder, a'pile elevator, a housing, a driving shaft in the housing, a gear loose on the driving shaft and rotatablel independently thereof, a driven shaft in the housing and connected with the pile elevator, a pair of gears fixed on th'edriven shaft in spaced relation, an intermediate shaft in the housing having a pair of -gears fixed thereon, in spaced relation and an intermediate loose gear continuously meshingy with one of the gears on the ydriven shaft, a pawl and ratchet mechanism on the driven shaft, means for connecting the pawl and ratchet -mechanism with and operating it from the loose gear on the driving shaft', and means .for selectively driving a fixed or the loose gear on the intermediate shaft or a fixedv gear on the driven shaft from the driving shaft, whereby said driven'shaft may be rotated intermittently in one direc-tion to intermittently raisethe pile elevator or continuously in opposite directions to vcontinuously raise or lower said pile elevator.

7. In a sheet feeder, a pile elevator, ya housing,

a driving shaft inthe housing, a gear loosev on the driving shaft and rotatable independently thereof, va drivenshaft in the housing and con-Y nected with the pile elevator, a pair of gears fixed on the driven shaft in spaced relation, an inter-l mediateshaft in the' housing having a pair of `gears fixed thereon in spaced relation and an intermediate loose lgear continuously meshing with one of the gears on the driven shaft, a pawl and ratchet mechanism on the driven shaft, means'for connecting the pawl and ratchet mechanism with land operating it from the loose gear on the driving shaft, means for selectively driving a fixed or the loose gear on 'the intermediate shaft from said driving shaft, whereby said driven shaft Amay be rotated intermittently in one direction to raise the pile elevator or con\l tinuously in the opposite direction to lower said\ pile elevator, and means on the housing for disconnecting the pawl and ratchet mechanism when' said driven shaft is rotated continuously in the opposite direction.

8. In a sheet feeder, a pile elevator including driven elements at thetop oir-thefeeder, mechanism at the bottom of the feeder includinga pawl and ratchet device connected with said elements for intermittently operating the same, and pile controlled means associated with said mechanism for controlling the operation of said pawl and ratchet device.

.9. In a sheet feeder, a pile elevator, a power unit for operating the pile elevator comprising a housing, a driving shaft in the housing, a mointermediate shaft in the housing and connected with the pawl and ratchet mechanism -to drive the same, a fixed gear on the intermediate shaft, a loose gear on the intermediate shaft continuously meshing with one of the fixed gears on the driven shaft, a pair of gears fixed on and slidable along the driving shaft for selectively engaging the fixed gear on the intermediate shaft-the loose gear thereon or the other fixed gear on Athe driven shaft, whereby said driven shaft maybe-rotated intermittently in one direction or continuously and rapidly in opposite directions, and a lever on the housing for shifting the `slidable gears along the driving shaft in opposite directionsand for simultaneously connecting and disconnecting the pawl and ratchet mechanism.

10. In a sheet feeder, a pile elevator, a powerunit for operating the -pile elevator comprisingA a housing, a driving shaft in the housing,y a motor on the housing and connectedwith the driving shaft to drive the same, la Iclutch on the driving shaft for connecting and disconnecting the motor relative to said shaft, a driven shaft in the `housing and connected with the p ile elevator, a

pawl and rachet mechanism onthe driven shaft for intermittently rotating said shaft in one direction to intermittently raise the pile elevator, a pair of gears fixed on the driven shaft in spaced f relation for continuously and rapidly rotating said shaft in opposite direotionsjto continuously and rapidly lraise and lower thepile elevator, an intermediate shaft in the housing and connected with the pawl and ratchet; mechanism todrive the same, a fixed gear on theintermediate' shaft, a loose gear on the intermediate shaft continuously meshing with one of the fixed gears on the driven shaft, a pair of gears fixed on and slidable along the driving Shaft for selectively engaging the fixed gear on the 'intermediate shaft, the loose gear thereon-or the other fixed gear on the driven shaft, whereby said driven shaft may be rotated intermittently in one direction or continuously and rapidly in opposite directions,-a'lever on the housing for connecting and disconnecting the clutch, and a lever on the housing for shifting the slidable gears along the driving shaft in opposite directions and for simultaneously connecting and disconnecting the pawl and ratchet mechanism.

1l. In combination, a housing, a driving shaft in the housing, a driven shaft in the housing and having two gears fixed thereon in spaced relation, a pawl and ratchet mechanism on the driven shaft, an intermediate shaft in the housing, a fixed gearand a loose gear on the intermediate shaft, the loose gear continuously meshing with one of the fixed gears on the driven shaft, means for connecting the -pawl and ratchet mechanism with and operating it from the intermediate shaft, and a pair of gears xed on and slidable along the driving shaft to various positions for selectively driving the fixed gear or the loose gear on the intermediate shaft or the other fixed gear on the driven shaft from said driving shaft, whereby said driven shaft may be rotated intermittently in Aone'direction or continuously in 13. In combination, a driving shaft, a driven shaft, a paw] and ratchet device on the driven shaft, and slidable gear means interposed between the driving and driven shafts and'selectively operable to drive the driven shaft continuously in one or the other of two directions from the driving shaft or intermittently therefrom in one of said directions through said pawl and ratchet device.

14. In combination, a driving shaft, a driven shaft, a pawl and ratchet device on the driven shaft, gear means interposed between the driving and driven shafts and selectively operable to drive the driven shaft continuously from the driving shaft or intermittently therefrom through said paWl and ratchet device, and means for disconnecting the pawl and ratchet device when said driven shaft is continuously driven. LEONARD BAKER.