US3409290A

US3409290A - Sheet stacking apparatus

Info

Publication number: US3409290A
Application number: US593986A
Authority: US
Inventors: Harry R Bergland
Original assignee: Burroughs Corp
Current assignee: Unisys Corp
Priority date: 1966-11-14
Filing date: 1966-11-14
Publication date: 1968-11-05
Anticipated expiration: 1985-11-05

Description

Nov. 5, 1968 H. R. BERGLAND 3,409,290

SHEET STACKING- APPARATUS Filed NOV. 14, 1966 4 Sheets-Sheet l m; I a-rim (alum-mun u I N VENTOR.

BYHARRY R. BERGLAND.

A TTORNEY,

Nov. 5, 1968 H. R. BERGLAND 3,409,290

SHEET STACKING APPARATUS Filed NOV. 14, 1966 4 Sheets-Sheet z INVENTOR.

HARR) R. BERG'LAND.

Maw

ATTORNEY.

Nov. 5, 1968 H. R. BERGLAND 3,409,290

SHEET STACKING APPARATUS Filed NOV. 14, 1966 4 Sheets-Sheet 5 INV OR.

HARRY R. BER 0. BY

A T TORNE).

NOV. 5, 1968 BERGLAND 3,409,290

SHEET STACKING APPARATUS Filed NOV. 14, 1966 4 Sheets-Sheet 4 INVENTOR.

BY HARRY R. mam/m.

United States Patent hangar DisoLosuREQ Thedisclosure embodies "a high speed'sheet stacking mechanisinof the'type in which sheets are fed singly in sequential order into an expansible bin.

' [The invention resides in the provision of a sheet stacking bin having one sidef formedby a movable member or belt carrying abutments or sockets to receive and guide the leading edges of the sheetsto the end of the bin to materially reduce sheet rebound and maintain sequential order of the sheets.

- One of the objects of the invention is to provide for a sheet handling apparatus in which sheets are transported singly along a path of, travel, an improved high speed sheet stacking device of a structural character to eliminate the rebound of sheets from a bin end wall without need of sheet shock absorbers. .fl-

Another object of the invention isto provide for a sheet handling apparatus in which sheets are fed sequentially along a path of travel, an improved sheet stacking apparatus of a character to eliminate the stacking of sheets out of sequential order.

A further object of the invention is to provide an improved high speed sheet stacker in which each sheet is fed and under positive control to its stacked position as opposed to free flight stacking of sheets.

In connection with the next preceding object, it is a specific object of the invention to provide for a high speed sheet stacker, an endless belt forming one side of a stacking bin and carrying a plurality of longitudinally spaced apart socket members to receive the leading edges of respective sheets fed into the bin.

Other objects of the invention will become apparent from the following detail description, taken in connection with the'accompanying drawings in which:

FIG. 1 is a plan view of the sheet stacking apparatus;

FIG. 2 is an elevational view partly in section, taken along the line 2-2 of FIG. 1;

FIG. 3 is a horizontal sectional view, taken along the line 3-3 of FIG. 2;

FIG. 4 is an enlarged fragmentary plan view showing a sheet in the process of being stacked;

FIG. 5 is a view similar to FIG. 4 showing the sheets advancement in the stacking operation;

FIG. 6 is a vertical sectional view, taken along the line 6-6 of FIG. 1, and

FIG. 7 is an enlarged horizontal sectional view, taken along the line 7--7 of FIG. 6.

In the drawings, the numeral 10 designates a base plate on which is mounted a sheet feed transport system including a driven belt 12 and a pressure belt 14. The

belts

12 and 14 are of the endless type and are relatively laterally positioned with opposed surfaces in broadside contact with each other to receive a sheet 15 therebetween. The belt 12 travels about end drive and driven pulleys 16 and 18 respectively, and a guide pulley 20 is provided on the drive side of the belt 12 to maintain contact between the belts. As shown in detail in FIG. 6, the pulley 16 is afiixed onto a vertical driven shaft 22 which is suitably journaled on the base plate 10 where a suitable pulley 3,409,290 Patented Nov. 5, 1968 and belt drive connection 24 may be used to connect the shaft to a motor 25. The pressure belt 14 travels about

end pulleys

26 and 28 and is guided by

intermediate guide pulleys

30 and 32. As shown in FIG. 1,' the guide pulley 32 is positioned to cooperate with the guide pulley'20 to maintain the belts in contact with each other for gripping and feeding sheets. The contacting sides of the

belts

12 and 14 pass between spaced apart

guide members

34 and 36 which guide sheets to an inlet 38 to a sheet stacking bin, designated generally by the numeral 40.

The bin 40 includes a movable sheet back-up member 42 which extends laterally of the direct-ionof travel of sheets into the bin by the

belts

12, 14, and thebin further includes an end Wall 44 which, in the present construction, is carried by the back-up member. Springs 48 or other suitable means may be employed to bias the back-up member 42 in a direction to yieldingly oppose increase in the sheet stack.

In accordance with the invetnion, a belt 50 is provided and arranged to form the sideof the bin opposite the back-up member 42 and carries a plurality of abutments or'socket forming members, or flexible tabs 52 to receive the leading edges of sheets enroute to the bin. The belt 50 travels about a pair of

end pulleys

54 and 56 of which the pulley 54 is freely rotatable on the driven shaft 22 and the pulley 56 is freely rotatable on an upright fixed shaft 58, adjacent the bin end wall 44. An intermediate guide pulley 59 is positioned to guide the belt 50 such that the belt travels longitudinally of the back-up member 42 from the bin inlet 38 toward and beyond the bin end wall 44. As shown, the tabs 52 project into the bin 40 in a rearward direction with respect to the direction of travel of the belt 50 at the bin, and the tabs form V-shaped sockets 60 with the belt proper. The flexible tabs provide expansible-contractable sockets the purpose being to grip a leading end portion of a sheet as the tab is flexed inward by the pressure of the back-up plate and stack. Preferably, the belt 50 is made of a flexible material, such as Mylar.

Further in accordance with the invention, the belt 50 is driven at a slightly less linear speed than the linear speed of the

sheet feed belts

12, 14 so as to insure that the leading edge of a sheet will engage and/or overtake one of the sockets 60. For example, on occasions a tab 52 and the leading edge of a sheet may be in such timed relationship that the leading edge of the sheet would engage in a socket 60 at about the tangency of

pulleys

16 and 30. However, when the leading edge of a sheet arrives at the tangency of

pulleys

16 and 30 between a pair of adjacent tabs 52, the above mentioned differential in linear speeds of

belts

12 and 50 makes it possible for the feed belts to advance the sheet relative to belt 50 until the leading edge of the sheet engages in the next preceding socket. The differential in linear speeds of the belt 50 and the

feed belts

12, 14 may be achieved by any suitable well known means. In the present construction, shown in FIG. 6, the belt 50 is driven from pulley 16 through a pair of

integral pulleys

62 and 64 which are freely rotatable on a fixed shaft 65, mounted in the base plate 10. The pulley 62 is driven from the pulley 16 by means of a belt 66 and the other or upper pulley 64 drives the pulley '54 through a drive belt 68. As shown, the upper pulley 64 is of lesser diameter than the lower pulley 62 so as to effect a correspondingly lesser linear speed of belt 50 than the linear speed of the

sheet feed belts

12 and 14. It will now be appreciated that the leading edge of each sheet will lodge in a socket 60 of the relatively slower moving belt 50 without need of precise timing of the sheets and the sockets.

Operation In operation of the sheet handling apparatus, sheets are fed singly into the guideway formed by members 34.

and 36 and are fed along the guideway by the

belts

12, 14 toward the inlet 38 to the bin 40. As the belt 50 travels about the pulley 54, the resultant compression and tension on the inner and outer surfaces of the belt causes the tabs 52 to flex outwardly into the sheet guideway in the path of the leading edge of a sheet being fed along the guideway. Since, as previously mentioned, the

feed belts

12, 14 travel at a higher linear speed than the belt 50, the sheet is advanced relative to belt 50 until the leading edge of the sheet engages the next preceding socket 60. The

feed belts

12, 14 continue to feed the sheet against the tab of the slower moving belt 50 which causes the sheet to bow, as illustrated in FIGS. 4 and 5. When the leading edge of the sheet strikes the end wall 44 of the bin 40, the sheet is released from its socket as belt 50 moves beyond the bin rear wall 44 The

feed belts

12, 14 continue to feed and bow the sheet until the trailing end of the sheet is discharged from the guideway inlet and belt 14, at pulley 26 flips the end of the sheet toward the stack. As each sheet is added to the stack, the sheet back-up member is moved outwardly by the increase in stack pressure thereon. This pressure also flexes the tabs 62 into the plane of the belt 50, whereupon the sheet is gripped and held between a tab 62 and the belt proper 50 with a force which opposes rebound of the sheet when the latter strikes the bin end wall 44. At this time the tab starts to pull away from the sheet and is still opposing the rebound tendency of the sheet. As previously mentioned, the tabs 62 are automatically flexed outward as they pass around the

pulleys

56 and 54 and thus one of the tabs is in position to receive the leading edge of a sheet entering the bin 40.

What is claimed is:

1. In a high speed sheet handling apparatus, apair of spaced apart laterally disposed guide members defining a. substantially rectilinear path of. travels-for.-sheetsafed singly therealong on edge, said guideway having a sheet discharge end positioned at an acute angle to the guideway, a pair of endless belts oppositely disposed along said guideway to feed sheets therealong, a first driven pulley driving one of said belts at a predetermined speed and positioned in the area defined by said acute angle, a second driven pulley having its axis of rotation coincident with the axis of rotation of said first drum pulley and projecting into the end portion of said guideway laterally of the latter, a third endless belt extending around and driven by said second driven pulley and restricting said discharge, said third endless belt constituting a moving feed side of a sheet stacking bin at an acute angle to said guideway and driven at a speed less than the speed of said one belt in the same direction as the latter, a plurality of spaced apart resilient members carried by said third belt on the outer side thereof forming V-sockets to receive a leading edge portion of a sheet, and a sheet back-up member overlying the feed side of said third belt and biased to yieldingly flex said resilient members toward the plane of the feed side of said third belt.

References Cited UNITED STATES PATENTS 1,462,923 7/ 1923 Stevens 2 271- 2,421,874 6/1947 Fouse 2716 9 3,167,012 l/1965 Claybourn 271-79 X FOREIGN PATENTS 700,816 12/1964 Canada. 191,863 2/1938 Switzerland.

EVON C. BLUNK, Primary Examiner. R. I. HICKEY, Assistant Examiner.