US1922041A

US1922041A - Sheet feeder

Info

Publication number: US1922041A
Application number: US450961A
Authority: US
Inventors: Charles W Harrold
Original assignee: Harris Seybold Potter Co
Current assignee: Harris Corp
Priority date: 1928-04-10
Filing date: 1930-05-09
Publication date: 1933-08-15
Anticipated expiration: 1950-08-15

Description

SHEET FEEDER imig'mal Filed April 10, 1.928 2 Sheets-Sheet 3 INVENTOR W PLTTORN EY Aug. 15, 1933. Q w HARROLD 1,922,041

SHEET FEEDER Original Filed April 10, 1928 2 Sheets-Shae}, 2

INVENTOR CHIQLIES l W/ Wow ATTORNEY Patented Aug. 15, 1933 UNITED STATES FATE NT OFFICE SHEET FEEDER Original application April 10, 1928 Serial No. 268,825. Divided and this application May 9, 1930. Serial No. 450,961

9 Claims (Cl. 271-53) My present application for patent is a division of my pending application Serial Number 268,825 filed April 10, 1928.

My invention relates generally to improve- 5 ments in sheet feeders for automatically advancing successive sheets of paper or other impression-receiving material to printing, folding or ruling machines, or to such other forms of machines as are devised to operate thereafter on such sheets, and more particularly to mechanisms for positioning the advanced sheets about to be seized by printing machines so that they will be printed in accurate register as is especially required in multicolor printing presses. The devices which I have shown are intended to position the sheet longitudinally only since the devices for positioning same laterally are no part of my present invention, and therefore are not shown. My improvements may be used with any form of sheet separator by which sheets are separated from a pile or bank and then presented one by one to the cylinder of a printing press which may have various forms of printing couples.

The objects of my invention are, among other things, to provide a sheet feeder of this character embodying separate devices capable of performing accurate and eilicient work in so presenting the sheets with great rapidity to the impression or feeding cylinders of printing machines so that each sheet will be seized or gripped while at rest by the sheet-taking devices of the cylinder in the same accurate register or relation to such cylinder as all other sheets. i

A further feature of my invention is to provide j an oscillating feed member having grippers which are adapted to close on the stationary sheet when the feed member is completing the last part of its reverse movement, such grippers having adjustable stops which will strike the edge of the stationary sheet so as to bring such sheet readily into front register against such stops while the feeding mechanism has a slight rearward movemefit and the grippers are closing on the sheet; thereafter the feed member on its forward movement delivers the registered sheet to the press cylinder as hereinbefore described. By this improved mechanism the feed-member in its reverse stroke is overfed against the edge of the sheet as the grippers close, and thereafter follows an overfeeding of the feed member against the press cylinder when transferring the sheet to such cylinder on its forward stroke. 7

In the drawin s'Fi l is an end elevation of my improved sheet-feeding and positioning mechanisms looking'from the rear of the machine;v

, Fig. 2 is an enlarged side view showing the feed member grippers closing on the sheet as the feedmember is being moved at the end of its rearward stroke against the leading edge of the sheet; and Fig. 3 is a detail section on the line 3-3 of Fig. 1 illustrating a stop device for the feed member to bring same to a positive stop when its grippers take the sheet.

Similar numerals refer to throughout the several figures.

Referring to the drawings, the successive top sheets 17 are separated and advanced into the usual feed rolls by any convenient mechanisms (not shown). These sheets 17 are then carried over the guide plate 51 to the feeding mechanism proper.

The feeding mechanism for taking the sheets 17 after they have been advanced and registered against the stop fingers 57 comprises the following devices: The rock-shaft 96 is journalled in the

side frames

34 and 35 and adjustably secured to the shaft 96 by the screws 97 are the oscillatable, radially-disposed feed mem- 30 bers 98 (six being shown in Fig. 1) which are similar in construction and operation. Mounted on the shaft 96 are the feed sectors 99 in which the gripper rock-shaft 100 is journalled as shown in Fig. l. The sheet grippers are bell crank inv shape, the upper arm 101 carrying the roller 102 while the lower extension forms the gripper fingers 103; the upper arm 101 is fastened to one end of the rock-shaft 100 and the coiled compression spring 104 (Fig. 2) holds the gripper roller 102 against the cam-lug mounted on a lever arm actuated by the lever 90 from the cam 90A so that the gripper fingers 103 will close and grip the front margin of the sheet 17 along its under-. surface and clamp same against the lower ends of the feed members 9 8. Due to a lost-motion slot arrangement in the lug 89 there will be no movement of the stop fingers 57 until the pin 89 on the lever 90 is in contact with the lower edge of the slot m lug so which will then draw down the arm 87 and cause a rotation of the shaft 82 so that the stop fingers 57 are swung forwardly and lifted out of the path of the sheet 17 which has been advanced and is at rest in registered position against such stop fingers.

A sheet-forwarding movement is then given to the rock-shaft 96 and also to the oscillating feedmembers 98 carrying thesheet held by the gripper fingers 103 by the following mechanism: 110 Keyed to the shaft 96 is the pinion 104 which 65 similar parts engages the toothed sector 105 pivoted to the short shaft 106 fixed to the side-frame 35. Also pivoted to the shaft 106 is the cam arm 107 carrying the cam-roller 108 which rides in the camgroove 134 formed in one end of the impression cylinder 28.

The sector 105 is rocked up and down through the revolutions of the impression cylinder 28, such sector 105 giving the gripper fingers 103 seizing the sheet a greater peripheral speed than the surface speed of the cylinder 28. The outer end of the cam arm 107 is provided with a bolt 110 which slides through the hole 111 formed in the bracket 112 of the sector 105 and the compression spring 113 coiled about the bolt 110 between the bracket 112 and the adjusting nuts 114 tends to force the end of the cam-arm 107 against the plate 115 formed at the lower end of the sector 105, while in another part of the cycle the camarm 107 is raised from the plate 115 while putting the spring 113 under compression. The purpose of this compensating device in the operation of the toothed sector 105 under the influence of the cam 134 will hereinafter be set forth.

The gripper devices for the impression cylinder 28 comprise the gripper fingers 121 mounted on the gripper bar 122 journalled in the cylinder 28; fastened to the bar 122 is the rock arm 123 .carrying the roller 124 to engage the cam 125 secured to the side-frame 35. The roller 124 is held in engagement with the cam 125 by the spring 126 as shown in Fig. 2. When the sheet 17 is carried to its forward position, the roller 124 rides off the cam 125 and the gripper fingers 121 close on the front margin of the sheet.

To ensure perfect gripping and releasing of the sheet with proper registration for the sheet, the movements of the oscillating feed members 98 and the revolutions of the impression cylinder 28 must be properly coordinated. The cylinder 28 rotates continuously while the sector 105 remains at rest except when the roller 108 travels through the irregular path of the cam-groove 184.

- 7 Such path causes an up and down movement for the sector 195 and an oscillating motion for the feed-members 98 at an accelerated speed with respect to the impression cylinder 28.

The shape of the cam-groove 134 carrying the roller 108 is so proportioned that the face speed of the grippers on the feed members 98 is accelerated so that such grippers are travelling at a greater speed than the surface speed of the impression cylinder '28 as the grippers approach this v cylinder to deliver the sheet, such overfeed or explunger pin 130 on the arm 129.

cess speed being taken up by the compensating mechanism now to be described. Loosely mounted on the shaft 96 adjacent the side-frame 34 is the gear 127 which meshes with the gear 81 keyed to the impression cylinder shaft 27. The gear 127 carries the tapered or bevel-surfaced lug 128 while the adjacent feed-sector 99 carries the upwardly extended arm 129 provided with a springactuated plunger pin 130. When the gripper fin- V gers 103 are gripping the sheet against the feedroller 108 and the sector 105 together with the feed-member 98 and sectors 99 begin to move forwardly, such movement becoming accelerated through the revolutions of the gear 127 until the plunger pin 139 on the arm 129 overtakes the lug 128 and the shank of the plunger pin 130 engages the straight side of the lug 128 so as to cause a pressure through the teeth of the

gears

127 and 81; These teeth in the gear 81 form fixed stops controlling the position of the lug 128 and thereby position the oscillating feed members 98 with the lug 128 controlling the registration of the sheet as it is delivered to the cylinder 28.

The feed sector 99 through this plunger 130 connection is therefore held in close contact with the lug 128, and this relation continues while rotating through a portion of the cam-groove 134.

Because of the irregular surface of the camgroove 134 the travel or speed of the feed sectors 99 would not exactly coincide with that of the gear 127, butthis difference is compensated by the differential mechanism in conjunction with the spring bolt 110 and cam-arm 107 construction which I have hereinbefore described.

Referring to Fig. 2, my improved means for operating the oscillating feed-mechanism is shown in which adjustable stops 131 are affixed to the ends of the feedmembers 98 by regulating screws 132, and the feed-members 98 are also provided with rearwardly extending guides 133. 1 The cam-groove 134 in the cylinder 28 is formed so that the dwell point 135 is somewhat exaggerated and a secondary reverse movement for the feed-members 98 through the downward movement of the sector 105 is shown at the end of the 1 reverse stroke by the slight depression 136 immediately following the dwell point 135 where the feed-members 98 normally stop their rearward travel. By this construction the stops 131 are backed against the front edge of the stationary sheet 17 through this slight retrograde movement of the feed-members 98, and while the gripper fingers 103 are closing on the sheet. It is also of advantage to keep the body of the sheet from movement while this short back-up of the feed members 98 is taking place against the sheet and the gripper fingers 103 are closing on the sheet. To so hold the sheet 17, I have provided the transverse shaft 157 which is free to rock in the

side frames

34 and 35.

Airlxed to the shaft 157 are a series of spacedapart sheet-holders 158 (only one being shown in Fig. 2) which carry the stops 159 that are adapted to be lowered to bear on the sheet 17 and hold same against the guide plate 51. The cam-arm 160 is mounted on the shaft 157 and has pinned thereto the cam-roller 161 which engages the cam 162 fastened to the rock shaft 96. The spring 163 pinned to the arm 160 holds the cam-roller 161 on the cam 162. When the roller 161 rides out of the drop of the cam 162 the stops 159 are raised to release the sheet 17 then under the control of the feed members 98 and gripper fingers 103.

In operation the sheet 17 is advanced to the stops 131 and is side-registered by any suitable devices (not shown) as the sheets are being sideregistered, the cam-roller 108 will drop into the depression 136 giving a slight backward movement to the shaft 96 and feed-members 98 thereby bring the front edge of the sheet 17 in front register with the stops 131 when the grippers 103 are closing on the sheet. At this part of the cycle the stops 159 are holding the body of the sheet and when the stops 131 move rearwardly the front margin of the sheet is slightly buckled (Fig. 2) while the leading edge is thereby front-registered against the stops 131. As the feed-members 98 move forwardly with the gripped sheet, the stops 159 are raised to release the body of the sheet as hereinbefore described when the roller 161 rides out of the drop of the cam 162. The adjusting screws 132 enable the stops 131 to be shifted relatively to the feed-members 98 to change the front register of the sheet relatively to the impression cylinder 28.

Referring to Fig. 3 I have shown a stop device for the feed-members 98 located on the rock shaft 96. The ratchet-collar 137 is secured adjustably to the shaft 96 adjacent the side-frame 34 and has the single tooth 138 out therein; the springpressed pawl 139 is pivoted on the eccentric stud 140 journalled in side-frame 34. The ratchet collar 13'? is set on the shaft 96 in relation with the pawl 139 so that the feed-members 98 will always come to a positive stop to ensure accurate register when the gripper fingers 103 take the sheet as shown in Fig. 3. The shifting of the stud 140 provided a fine adjustment for the pawl 139 to vary the rearward stroke of the feed-members 98.

I claim as my invention:-

1. In a sheet feeder, sheet-holding means, an oscillatable sheet-feeding member having sheet grippers, means for shifting said member further rearwardly against the sheet at the end of the reverse stroke, and means for closing said grippers on the sheet during said reverse stroke of said member.

2. In a sheet feeder, sheet-holding means, an oscillatable sheet-feeding member having sheet grippers, means for shifting said member further rearwardly against the sheet at the end of the reverse stroke, and means actuated independently of said feeding member for closing said grippers on the sheet during said reverse stroke of said member.

3. In a sheet feeder, sheet-holding means, a sheet-receiving cylinder, an oscillatable sheetfeeding member having travelling stops, means for moving said member and stops further rearwardly against the front edge of the sheet at the end of the reverse stroke to aline same against the stops, and means for actuating said feedingmember to deliver the sheet on the cylinder.

4. In a sheet feeder, sheet holding means, a sheet-receiving cylinder, an oscillatable sheetfeeding member having travelling stops, means for moving said member and stops further rearwardly against the front edge of the sheet at the end of the reverse stroke to aline same against the stops, and means for actuating said feedingmember in a forward direction to deliver the sheet on the cylinder.

5. In a sheet feeder, an oscillatable sheetfeeding member having sheet grippers, means for moving said member further rearwardly against the sheet at the end ofthe reverse stroke, and means for holding the body of the sheet against movement as the grippers close on the sheet.

6. In a sheet feeder, an oscillatable sheet-feeding member having sheet grippers and travelling stops on said member, means for moving said member and stops further rearwardly against the sheet at the end of the reverse stroke, and means for holding the body of the sheet against movement as the grippers close on the sheet.

'7. In a sheet feeder, sheet-holding means, an oscillatable sheet-feeding member having sheet grippers, and means for shifting said member further rearwardly at the end of the reverse stroke While the grippers are closing on the sheet.

8. In a sheet feeder, sheet-holding means, an oscillatable sheet-feeding member having sheet grippers and travelling stops on said member, and means for moving said member and stops further rearwardly against the sheet at the end of the reverse stroke while the grippers are closing on the sheet.

9. In a sheet feeder, sheet-holding means, an oscillatable sheet-feeding member having sheet grippers and travelling stops on said member, and means for moving said member and stops further rearwardly against the sheet at the end of the reverse stroke and moving the sheet in a reverse direction to aline the sheet against the stops while the grippers are closing on the sheet.

CHARLES W. HARROLD.