US2336499A - Sheet feeding device - Google Patents

Description

Dec. 14, 1943. w, MURCH A 2,336,499

SHEET FEEDING DEVICE Filed Jan. 20, 1942 6 Sheets-Sheet 1 1 'ENTO- BY 2 m awn M Dec. 14, 1943. H UR H ET AL 2,336,499

SHEET FEEDING DEVICE Filed Jan. 20, 1942 e sh ets-sheetz Dec. 14, 194-3. J MURCH AL 2,336,499

SHEET FEEDING DEVICE Filed Jan. 20, 1942' 6 Sheets-Shae; 3

INVENTO 5 De. 14, 1943. m. 2,336,499

SHEET FEEDING DEVICE Filed Jan. 20, 1942 Y e Sheets-Sheet 4 A TTOENEYS Dec. 14, 1943.

fig-9 J. H. 'MuRcH ETAL 'sHEET FEEDING DEVICE Filed Jan. 20, 1942 6 Sheets-Sheet 5 '7 I gvvENToR BY 2% Y W M E Dec. 14, 1943. J, H. MURCH ET AL SHEET FEEDING DEVICE Filed Jan. 20, 19425 6 Sheets-Sheet 6 TTOENE'YS Patented Dec. 14, 1943 UNITED s'r S PATENT OFFIC SHEET FEEDING DEVICE Application January 20, 1942, Serial No. 427,502

11 Claims.

The present invention relates to a sheet feeding device for container or can making machines and has particular reference to feeding sheets at high speeds without nicking them.

In the manufacture of cans the blanks from which the bodies are made are usually fed by a reciprocating stroke bar from a stack of such blanks contained in a magazine. At high speeds of production the feed dogs on the rapidly moving stroke bar engaging against a stationary blank to feed it from the magazine usually dent or nick the edge of the blank and this nick causes trouble during subsequent operations on the blank.

The instant invention contemplates overcoming this difficulty by providing a magazine or auxiliary feed stroke bar moving relatively slowly and through a short stroke and which operates in cooperation with the regular high speed feed bars on the machine and which keeps the blank moving after being fed from the magazine until the regular feed bars pick up the blank and carry it forward.

An object therefore of the invention is the provision in a can making machine of a high speed blank feeding device wherein blanks contained in a magazine are removed individually by a relatively slow moving auxiliary feed bar which advances and keeps the blank in motion while the regular high speed feed bars on the machine engage and further advance the blank so that denting or nicking of the blank edge is prevented.

Another object is the provision of such a blank feeding device wherein auxiliary suction cups are used in cooperation with the usual separator suction cup for pulling down the outer edge portions of a blank contained in a magazine so that the lowermost blank will be positively separated from the blank next above to prevent the feeding of double blanks.

Another object is the provision of a blank feeding device wherein auxiliary suction cups are used in cooperation with the usual separator suction cup for pulling down the outer edge portions of a blank contained in a magazine so that the lowermost blank will be positively separated from the blank next above to prevent the feeding of double blanks.

Another object is the provision of a blank feeding device of this character wherein the auxiliary suction cups for separating a blank from the others in a magazine are supplemented by air blast nozzles which direct blasts of air against the edges of the blank being separated to vibrate the blank and thus insure its positive separation.

Numerous other objects and advantages of the invention will be apparent as it is better understood from the following description,

which, taken'in connection with the accompanying drawings, discloses a preferred embodiment thereof.

Referring to the drawings:

Figure 1 is a top plan view of a blank feeding device embodying the instant invention, with parts broken away;

Fig. 2 is a front elevation of the device shown in Fig. 1, with parts broken away;

Fig. 3 is a sectional view taken substantially along the broken line 33 in Fig. 2, with parts broken away;

Figs. 4 and 5 are sectional details taken substantially along the lines 4-4 and 5-5 in Fig. 3, with parts broken away;

Fig. 6 is an enlarged sectional detail of a valve used in the device, with parts broken away;

Fig. '7 is a side view of a detail of the device, the view being taken substantially along a plane indicated by the line 1-7 in Fig. 2, with parts broken away; I

Fig. 8 is a sectional View taken substantially along the broken line 88 in Fig. 2, with parts broken away;

Fig. 9 is a sectional View taken substantially along the line 9-9 in Fig. 2, with parts broken away;

Fig. 10 is a transverse sectional view taken substantially along the line iii-i0 in Fig. 3, with parts broken away;

Figs. 11 and 12 are enlarged schematic transverse sectional views taken substantially through the blank magazine of the device and showing different positions of the suction cups incident to separating and removing the lowermost blank from the magazine; and

Fig. 13 is a schematic perspective view of the feed bars and suction cups used in the device, with parts broken away.

As a preferred embodiment of the instant invention the drawings illustrate a blank feed for a sheet metal can body making machine of the character disclosed in United States Patent 1,770,041, issued July 8, 1930, to John F. Peters on Roll bodymaker. In such a machine flat sheet metal blanks A (Figs. 8, 11 and 12) are fed from the bottom of a magazine B and are propelled through the machine by a pair of spaced and parallel reciprocating high speed feed bars Ii (see also Figs. 3 and 13) having spring held feed dogs l2 spaced at intervals along their length. These feed bars slide in longitudinal groove I4 (see Fig. 10) formed in a horil5 and are connected with short links 2|. The links are connected to the upper ends of a pair of substantially vertical actuating arms 22 which are mounted on a cross shaft 23 carried in bearings 24 formed in the main frame l6.

One of the arms 22 is connected to a connecting rod 25 which is reciprocated in any suitable manner in time with the other moving partsof the machine, such as that disclosed in the above mentioned Peters patent. This connecting rod reciprocates the feed bars H and thus advances the blanks A in an intermittent or step-by-step manner through the machine for subsequent operations.

In the instant invention the blanks A are retained in the magazine B by a pair of upright corner guide bars 21 (Figs. 1, 3 and 8) and a guide plate 28 located opposite the rods. The corner bars 21 are secured to a pair of spaced and parallel longitudinal wall sections 28 (see also Fig. of the main frame IS. The guide plate 28 is located centrally between the wall sections 28 and is secured to a cross beam 3|, the ends of which are bolted to the wall sections.

The blanks A in the magazine B are supported on a pair of spaced and parallel support arms 33 which are located one on each side of the middle of the blanks and are bolted to a cross beam 34 secured to the corner guide bars 21. These support arms 33 hold the lowermost blank A in the stack just above the blank feed line so that the rear feed dogs I2 of the feed bars II will clear the blanks when they pass under the magazine on a return stroke.

The lowermost blank A in the magazine B is pulled down by suction cups to separate it from the other blanks in the stack and to bring it into the region of the feed line just prior to its withdrawal from the magazine. Separation of the lowermost blank is brought about by a pair of separator suction cups 38 (Figs. 1, 2, 3, 11, 12 and 13). These two suction cups are located just under the magazine and are disposed one adjacent each rear corner of the lowermost blank in the magazine,

The separator suction cups 3,8 are carried on swing arms 39 (Figs. 1, 2 and 3) which are mounted on pivot studs 4| threaded in bosses 42 formed on the table frame l5. The outer ends of the swing arms are connected by links 44 to vertical slides 45 (see also Fig. 4). There are two of these slides 45, one for each separator suction cup 38. These slides operate in slideways 46 formed in brackets 4'1 secured to the table frame IS. A cover plate 48 on each bracket retains the slides within their slideways.

The slides 45 are moved through an upward stroke to engage the lowermost blank in the magazine and thence through a downward stroke. This movement within their slide-ways 45 is effected by a pair of eccentrics 5! having connecting rods 52 which connect with the lower ends of the slides. These eccentrics are mounted on an eccentric shaft 53 which extends across the front of the machine and is journaled in three spaced bearing brackets 54 bolted to the main frame 15. The eccentric shaft is rotated in any suitable manner, such as by a gear 55, in time with the feed bars II and the other moving parts of the machine.

The slides 45 and the suction cups 38 are also in communication with a source of vacuum. For this purpose the suction cups 38 are connected by flexible tubes 58 to the slides 45. These tubes communicate with vertical passageways 59 (Fig.

3) one being formed in each slide. The lower end of each passageway 59 communicates with a flexible tube 6| which extends through a slot 62 in the cover plate 48 and which is secured in the slide. The opposite ends of the two tubes El connect with a pipe 64 (see also Fig. 6) which is threaded into a valve 65. The pipe communicates with a passageway 61 in the valve which opens into a pipe 68 leading from a suitable source of vacuum.

The valve 55 is provided with a valve plunger H which slides in a bore '12 formed in the valve and which extends across the passageway 67. The plunger normally cuts off communication between the vacuum pipe 68 and the pipe '54. However, the plunger is formed with an annular groove 14 which when brought into register with the valve passageway 57 by movement of the plunger, opens communication between the pipes 64, B8 to draw a vacuum on the suction cups 38.

This movement of the valve plunger H is brought about by a link 16 (see also Fig. 1) which is connected to an arm T1 of a rocker lever i8 mounted on a rocker shaft i9 carried in bearings 8| formed in the main frame it. This lever shaft is parallel with the eccentric shaft 53 and extends across the front of the machine. The shaft 19 is rocked in its bearings 8| in time with the other moving parts of the feeding device by an eccentric 83 (Figs. 1 and 9) which is mounted on the eccentric shaft 53.

This eccentric 83 is formed with a long stem 84 having at its outer end a head 85 which is located in a sleeve 86, connected by way of a pivot pin 8?, to an arm 88 of a rocker lever 89 mounted on the rocker shaft 19. A compression spring 9| surrounds the eccentric stem 84 and is located in the sleeve 86 between the stem head 35 and a locknut 92 on the end of the sleeve. This provides a flexible connection between the eccentric 83 and the rocker arm 88.

Hence as the slide eccentrics 5| on the rotating eccentric shaft 53 move the slides 45 through an upward stroke to bring the separator suction cups 38 into engagement with the two outer corners of the lowermost blank A in the magazine B, the eccentric 83 moves the rocker shaft 19 and the rocker lever arm 11. This shifts the valve plunger ll to bring its groove 74 into register with the vacuum passageway 61 of the valve 65. This opens communication between the vacuum pipe 68 and the pipe 64 and thus draws a vacuum on the suction cups 38 by way of the tubes 6|, slide passageway 59, and the tubes 58.

The vacuum thus created in the cups makes them adhere to the corners of the lowermost blank A.

While the separator cups 38 thus are holding the two outer corners of the blank A, the separator eccentrics 5| draw the slides 45 and the cups 38 thereon, downwardly through the return or separating stroke. This pulls the two outer corners of the blank A downwardly, as best shown in Fig. 11. While the corners are thus being drawn downwardly a blast of air is directed against each of the two front corner edges of the lowermost blank and those immediately above. This separates the lowermost blank from the others.

The blasts of air issue from two nozzles lfll (Figs. 1, 2 and 3) which are located adjacent the separator cups 38 and which are carried in brackets I02 secured to the blank supports 33. These nozzles are connected by pipes I03, )4 to a normally closed air valve H15 which is identical with the vacuum valve 65 and which is connected by way of a pipe I96 to a suitable source of compressed air. The air valve IE is fitted with a sliding plunger I83 which is connected by a link N59 to an arm III of the rocker lever I8 mounted on the rocker shaft 19.

Hence when the shaft I9 is rocked to open the vacuum valve I55 it also opens the air valve I55. It is this operation of the air valve that permits air from the pipe I96 to pass through the pipes IE3, Hi l and issue from the nozzles IIlI at the proper time to separate the blanks as hereinbefore mentioned.

While the two outer corners of the lowermost blank A are being drawn downwardly and separated from the blanks next above in the magazine B, the middle portion of the blank, is pulled downwardly in readiness for removal of the blank from the magazine. However, just prior to this removal of the blank, the vacuum on the separator cups 38 is broken to release the cups from the separated blank. This release of the cups will now be explained.

Breaking of the vacuum on the separator cups 38 is brought about by the opening of normally closed valves in the slide brackets 61. There are two of these valves, one for each slide bracket. Each valve includes a port II5 (Fig. 3) formed in the rear of the bracket and normally closed by a valve head H6 of a spring pressed plunger II! which is carried in an open bracket H8 secured to the rear of the slide bracket.

The plunger II! is connected to the lower end of 2. depending arm I2! (see also Fig. 5) which is mounted on a short pivot shaft I22 carried in a bearing I23 formed on the bottom of the table frame I5. There are two of these arms I2I, located one on each side of the feeding device. This provides for operation of the two valves independently. The pivot shafts I22 carry actuating arms I25 which are connected to long links I26 (see also Fig. 2). The link I26 on one side connects with an arm IZl of the rocker lever Id. The link on the other side is connected to an arm I28 of a rocker lever IZQ. Both levers i8 and I29 are mounted on the rocker shaft I3.

When the slides on which the separator cups 3% are mounted, move downwardly to pull down the corners of the blank A by the vacuum created in the cups, the valve head Ilt of the plunger I I? is in sealing position within the port H5 in the slide bracket. As the slides continue to move downwardly to the bottom of their stroke, the vacuum is held on the cups to keep the blank corners down until the blank is ready for removal from the magazine.

During this descent of the slide, a port I32 (Fig. 3) formed therein is brought into register with the port H5. The port I32 communicates with the slide passageway 59. With the port I32 in register, which takes place just as the blank begins to move out of the magazine, the valve head IIE of the plunger II? is drawn back from the port H5 by the rocking of its actuating arm I25. This admits air into the slide passageway 59 by way of the aligned ports H5, I32. It is this admission of air that breaks the vacuum in the separator cups 38 and thus releases the blank from the cups. When the vacuum thus is broken in the separator cups the valve is closed to out oi the cups from the source of vacuum.

The drawing downwardly of the lowermost blank A at its middle section is brought about by a main vacuum cup I35 (Figs. 1, 2, 8, ll, 12 and 13). This vacuum cup is located just under the magazine 13 at the middle of and near the forward edge of the lowermost blank A as it rests in the magazine. In this position of the vacuum cup it is centrally located between the two outer feed dogs I2 on the feed bars II.

The vacuum cup I35 is secured to the upper end of a vertical slide I36 (Fig. 8) which is identical with the two slides #15 connected with the separator suction cups 38. The slide is located in a slideway I3? formed in a bracket I38 secured to the bottom of the table frame I5. The slide is held in place by a cover plate I 39 secured to the outer face of the bracket.

The slide I 36 is raised and lowered in time with the other moving parts of the feeding device by an eccentric ring M2 (see also Fig. 2) which is connected to the lower end of the slide. The eccentric ring rotates on an eccentric I i-i mounted on the eccentric shaft 53. The slide i36 is formed with a cup vaouumizing passageway which is identical with the passageway 59 in the slide :15. This passageway leads from the cup I35 to one end of a flexible tube I 26. The opposite end of the tube is connected into a vacuum valve il (Fig. 2) secured to a pipe I 52 which leads to a suitable source of vacuum.

The vacuum valve I5I (see also Fig. 9) is identical with the other vacuum valve 35 hereinbefore mentioned and is fitted with a sliding valve plunger connected to an arm I54 of the rocker lever 89. It will be recalled that lever 89 is mounted on the rocker shaft I9. Hence when the slide I36 under the oscillation of rocker shaft I9, moves through an upward stroke and brings the vacuum cup I35 into engagement with the lowermost blank A in the magazine, the shaft It also rocks the lever arm I5 and shifts the valve plunger in the valve IEI to open position. This connects the vacuum cup I35 to the source of vacuum and thus makes the blank adhere to the cup.

On the following downward stroke of the slide E35, with the vacuum still maintained on the cup, the blank is drawn downwardly toward the feed line into the position shown in Fig. 12. By the time the bent middle portion of the blank reaches the feed line, a pair of spaced auxiliary feed dogs 35'! (Figs. 11 and 13) engage the rear edge of the lowermost blank and push the blank horizontally out of the magazine B. The auxiliary feed clogs I57 are carried in short relatively slow moving feed bars I58 which are located one on each side or the vacuum cup. It is at this time that the vacuum on the separator suction cups 38 is broken and the corners of the blank thereupon are released. At the same time the vacuum on the main vacuum cup I35 is broken and the blank is released from this cup.

The breaking of the Vacuum in the main vacuum cup I35 is brought about by registering a valve port in the slide I36 with another port in the slide bracket I33. These ports are identical in construction and operation to the ports H5, I32 in the bracket 4? and slide 25 hereinbefore explained. The valve port in the slide bracket l38 normally is closed by a valve head I62 formed on a spring held plunger I53 which is carried in an open valve bracket I65.

The outer end of the valve plunger I53 is secured to an arm I (see also Fig. 10) which is mounted on a short pivot shaft It? carried in a depending bearing I68 formed on the bottom of the table frame I5. The pivot shaft also carries of a long link I'I2 (see also Fig. 8). .The outer end of the link is connected to a rocker lever I'I3 (see also Fig. 2) mounted on the rocker shaft I9.

Rocking of shaft 79 and the corresponding movement of the link I12 and lever arms I66, I?! connecting therewith and with the valve plunger I63, opens the valve at the proper time and thereby admits air into the slide passageway leading to the vacuum cup I35. This breaks the vacuum therein and releases the blank from the cup. When the vacuum is broken in the vacuum cup I35, the valve II is closed to cut off the cup from the source of vacuum.

The auxiliary feed bars I58 (Fig. 13) which carry the feed dogs I51 are mounted on a horizontal slide block I16 formed with a depending tongue III which slides in a slideway IIS (see also Figs. 1 and 8). This slideway is formed in an extension I19 of the table frame I 5. The slide block is reciprocated through a short slow forward or feeding stroke and thence through a slow return stroke below the magazine B and in time with the other moving parts of the feeding device. For this purpose a depending lug I82 extends downwardly through an opening I83 in the table frame extension I19.

The lug I82 is connected by a link I84 with the upper end of a lever I85 mounted on a cross shaft I85 which extends across the front of the feeding device in parallelism with the rocker shaft I9 and with the eccentric shaft 53. The cross shaft is carried in bearings IB'I (Figs. 1 and 2) formed on the main frame I6. One end of the cross shaft I86 carries an arm I88 (see also Fig. 7) which has its outer end connected to an eccentric ring arm I89 of an eccentric I9I. The arm I89 operates on an eccentric shaft section between two spaced and parallel discs I92 formed in the eccentric shaft 53.

Thus as the eccentric shaft 53 rotates it rocks the cross shaft I85 and lever I85 carried thereon and thus reciprocates the auxiliary feed bars I58. On the forward stroke of the feed bars, the feed dogs I51 carried thereon engage against the rear edge of the bowed blank A and push the blank out of the magazine B and carry it forward. The dogs are formed with overhanging hook noses I95 (Fig. 13) to hold the blank against springing upwardly after its release from the suction and vacuum cups.

While the removed blank is still in motion the regular feed dogs I2 on the main feed bars II gently engage the rear edge of the blank and carry it forwardly through the machine in the regular manner. Due to the short stroke of the auxiliary feed bars I58 they are actuated at a slower rate of speed than the regular high speed feed bars II with their long stroke. It is this slower speed and this manner of feeding the blanks from the magazine with the short stroke auxiliary feed dogs that prevents nicking of the blanks. After delivering the blank onto the regular feed bars II, the auxiliary feed bars I58 move rearwardly under a return stroke and come into their original position in readiness for the next blank in the magazine.

A vacuum control is provided for preventing the feeding of the blanks from the magazine when it is desired. This feed stop is brought about by an electric solenoid I96 (Figs. 2 and 9) having a vertically disposed movable core I91. The core of the solenoid is located directly below a foot member I98 formed on the lower end of the rocker shaft actuating arm 88. The solenoid may a lever m which is connected to the inner end be connected by wires I89 to a suitable source of electric energy and to a push button switch and to the usual automatic stop switches in the bodymaker so that it may be energized by any or all of these switches when desired or when a jam or wreck occursin the machine.

Energizing of the control solenoid I96 shifts its core I91 up into the path of travel of the foot I98 of the actuating arm 88 as its rocker shaft'IS moves and thus stops further movement of the-arm. This holds the rocker shaft I9 against movement but the eccentric shaft 53 continues to rotate and the throw of the eccentric.

83 is taken up by the compression spring III in the sleeve 86.

With the rocker shaft thus held against movement, the rocker levers mounted thereon are stopped from operating. The vacuum valves 65, ISI and the air valve IE5 thus remain closed. Vacuum is not drawn on the suction cups 38 or on the vacuum cup I35 and hence the blanks in the magazine are not removed therefrom.

It is thought that the invention and many of its attendant advantages will be understood from the foregoing description, and it will be apparent that various changes may be made in the form, construction and arrangement of the parts without departing from the spirit and scope of the invention or sacrificing all of its material advantages, the form hereinbefore described being merely a preferred embodiment thereof.

We claim:

1. In a high speed sheet feeding device, the combination of a magazine containing a stack of sheets, a relatively slow moving auxiliary feed bar having a feed dog thereon for engaging and setting in motion the lowermost sheet in the magazine, and a high speed feed bar having a feed dog for gently engaging behind the started sheet while it is still in motion and for advancing it along a predetermined path of travel without the feed dogs nicking the sheet.

2. In a high speed sheet feeding device, the combination of a magazine containing a stack of sheets, means for separating the lowermost sheet in the magazine from the others, a relatively slow moving auxiliary feed bar having a feed dog thereon for engaging and setting in motion the separated sheet in the magazine, and a high speed feed bar having a plurality of feed dogs thereon for gently engaging behind the started sheet while it is still in motion for advancing it along a predetermined path of travel thus preventing nicking of the sheet by the feed dogs.

3. In a high sped sheet feeding device, the combination of a magazine containing a stack of sheets, a pair of suction cups located below said magazine and adjacent opposite corners of the sheets in the magazine for pulling down the corners of the lowermost sheet to separate this sheet from the others in the stack, a vacuum cup for pulling the separated sheet down toward a feed line, and feeding means for removing the separated sheet from the magazine and for advancing it along a predetermined path of travel on the feed line.

4. In a high speed sheet feeding device, the combination of a magazine containing a stack of sheets, a pair of suction cups located below said magazine and adjacent opposite corners of the sheets in the magazine for pulling down the corners of the lowermost sheet to separate this sheet from the others in the stack, a vacuum cup for pulling down on the midle part of the separated sheet, an auxiliary feed bar having a feed dog thereon for engaging and setting in motion the separated sheet in the magazine, and a main feed bar having a plurality of feed dogs for gently engaging behind the sheet already moving with said auxiliary feed bar and for advancing the sheet at an increased rate of travel, thus preventing nicking of the sheet by the feed dogs.

5. In a high speed sheet feeding device, the combination of a magazine containing a stack of sheets, a pair of suction cups located below said magazine and adjacent opposite corners, of the sheets in the magazine for pulling down the corners of the lowermost sheet to separate this sheet from the others in the stack, a vacuum cup for pulling the center of the separated sheet down toward a feed line, feedin means for removing the separated sheet from the magazine for advancing it along the feed line in a predetermined path of travel, and means for rendering said suction cups and said vacuum cup inoperative to prevent feeding of the sheets from said magazine.

6. In a high speed sheet feeding device, the combination of a magazine containing a stack of sheets, a plurality of vertical slides located below said magazine, means for actuating said slides, a pair of suction cups carried on two of said slides, said cups being disposed adjacent opposite corners of the lowermost sheet in the stack for drawing these corners down to separate the sheet from the others, a Vacuum cup carried on another of said slides for drawing the separated sheet down to a feed line, means for drawing a vacuum on said cups, valve devices for controlling said vacuum, a relatively slow moving auxiliary feed bar located adjacent said vacuum cup for setting in motion and for removing the separated sheet from the magazine, and a high speed feed bar for picking up the removed sheet whi e it is in motion without niclo ing the sheet and for advancing it along a predetermined path of travel in said feed line.

'7. In a high speed sheet feeding device, the combination of a magazine containing a stack of sheets, a plurality of Vertical slides located below said magazine, means for actuating said slides, said cup being disposed adjacent opposite corners of the lowermost sheet in the stack for drawing these corners down to separate the sheet from the others, a vacuum cup carried on another of said slides for drawing down the separated sheet adjacent its center to a feed line, means for drawing a vacuum on said cups, valve devices for controlling said vacuum, a short stroke relatively slow moving auxiliary feed bar located adjacent said vacuum cup for setting in motion and for removing the separated sheet from the magazine, a long stroke high speed feed bar for picking up the removed sheet while it is in motion to prevent nicking of the sheet and for advancing it along a predetermined path of travel in said feed line, and electric solenoid operated devices for holding said valve devices in closed condition to prevent drawing a vacuum on said cups and to prevent feeding of sheets from the magazine while the device is operating.

8. In a high speed sheet feeding device, the combination of a magazine containing a stack of sheets, a pair of suction cups located below said magazine and adjacent opposite corners of the sheets in the magazine, a pair of laterally spaced members under said stack and between said pair of cups for supporting said sheets, a third suction cup below said stack and between said spaced members for pulling d wnwardly a central portion of the lowermost sheet between said support members While each of said pair of cups is adapted to pull downwardly a corner of said lowermost sheet thereby to separate this sheet from those above it in the stack, and feeding means for removing this sheet from the magazine and for advancing it along a predetermined path of travel.

9. In a high speed sheet feeding device, the combination of a magazine containing a, stack of sheets, a pair of suction cups located below said magazine and adjacent opposite corners of the sheets in the magazine, a pair of laterally spaced members under said stack and between said pair of cups for supporting said sheets, a third suction cup below said stack and between said spaced members for pulling downwardly a central portion of the lowermost sheet between said support members while each of said pair of cups is adapted to pull downwardly a corner of said lower-- most sheet thereby to separate this sheet from those above it in the stack, an air blast device for ejecting a blast of air against a corner of the sheets in the magazine to insure separation of said lowermost sheet, and feeding means for removing this sheet from the magazine and for advancing it along a predetermined path of travel.

10. In a sheet feeding device, the combination of a magazine containing a stack of sheets to be fed for a subsequent operation thereon, a vacuum cup disposed beneath said magazine and connected with a source of vacuum for pulling down the lowermost sheet to separate it from other sheets in the stack, an auxiliary fee-d bar having a feed dog thereon for engaging and setting in motion the lowermost sheet in the magazine, a main feed bar having a feed dog for gently engaging behindthe started sheet while it is still in motion for advancing said sheet along a predetermined path of travel without the feed dogs nicking the sheet, a valve for controlling said vacuum, and an electric solenoid actuating device for holding said valv in closed position to prevent drawing a vacuum on said cup and to prevent feeding a sheet from said magazine whil said main feeding means is operating.

11. In a sheet feeding device, the combination of a magazine containing a stack of sheets to be fed for a subsequent operation thereon, a vacuum cup disposed beneath said magazine and connected with a source of vacuum for pulling down the lowermost sheet to separate the same from other sheets in the stack, an air blast device for ejecting a blast of air against an edge of the sheets in the magazin to insure separation of the lowermost sheet from the remaining sheets in the stack, an auxiliary feed bar having a feed dog thereon for removing the separated sheet from the magazine and for advancing the same, and a high speed feed bar having a feed dog for gently engaging behind the started sheet while it is still in motion and for advancing it along a predetermined path of travel Without the feed dogs nicking the sheet, a valve for controlling said vacuum, and an electric solenoid actuating device for holding said valve in closed position to prevent drawing a vacuum on said cup and to prevent feeding a sheet from said magazine while said high speed feed bar is operating.

JOHN H. MURCH. WILLIAM P, WINTERS.

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