US2775451A

US2775451A - Sheet feeding mechanisms

Info

Publication number: US2775451A
Application number: US385863A
Authority: US
Inventors: Styles Leonard Walter
Original assignee: NRG Manufacturing Ltd
Current assignee: NRG Manufacturing Ltd
Priority date: 1952-12-12
Filing date: 1953-10-13
Publication date: 1956-12-25
Anticipated expiration: 1973-12-25

Description

Dec. 25, 1956 L. w. STYLES SHEET FEEDING MECHANISMS 3 Sheets-Sheet 1 Filed Oct. 15, 1953 m/z/i/vrme Mow/mp (444L751? 573 455 Dec. 25, 1956 w. STYLES SHEET FEEDING MECHANISMS 3 Sheets-Sheet 2 Filed Oct. 13, 1953 INVENTOR LEON/4RD WALTER 570 455 ATfE/VEY Dec. 25, 1956 Filed Oct. 15, 1953 v w. STYLES SHEET FEEDING MECHANISMS 3 Shets-Sheet vs United States Patent Claims priority, application Great Britain 1 December 12, 1952 3 Claims. (:I. 271 -61) This invention concerns an edge support fora paper stack for use with a sheet-feeding mechanism, as for example for feeding sheets 1n succession to a duplicating machine.

Edge supports are well known which comprise a pad (one to lie on each side of the stack of paper) which rests on a support (e. g. a platform) the pads being adjustable towards and away from the edges of the paper stack by means of cams or other suitable arrangements. Such edge supports are provided to grip the stack of paper to ensure that the sheets are fed from the stack one at a time.

The object of the present invention is to provide an improved construction of edge support.

A disadvantage of known edge supports is their tendency, particularly after repeated use, for the sides of the stack of paper to be gripped unevenly due to tilting of the pads. Thus, the uppermost sheets at one side of the stack may be gripped too heavily and the lowermost sheets not at all while the opposite side of the stack may also be gripped unevenly and possibly in a different way. When this occurs the sheets are not fed under uniform conditions to the machine and the quality. of the duplication may be impaired. The object of this invention is to overcome this disability and ensure, even after extensive use, that both sides of the stack are uniformly gripped throughout the depth of the stack. Another object is to ensure that the gripping action extends to the lowermost sheet of the stack.

A practical application of the present invention will now be described, by way of example only, with reference to the accompanying drawings of which:

Figure 1 is a diagrammatical side view of a duplicating machine incorporating an edge support in accordance with the present invention,

Figure 2 is a perspective view showing the sheet feeding mechanism and the edge supports in greater detail,

Figure 3 is a front view of an edge support in accord ance with the present invention,

Figure 4 is a plan view of the device of Figure 3, and Figure 5 is a view in elevation looking from the left of Fig. 4.

being delivered in succession on to a stack 14 on a platform 15. The duplicating machine is of conventional design comprising an upper cylinder 16 and a lower cylinder 17, a handle 9 to drive the machine and a stencil holder 18 which secures a stencil around the

cylinders

16 and 17. An edge support in accordance with the present invention is generally indicated at Figure 1 by the reference numeral 19.

Referring now to Figure 2: the sheet feeding mechanism comprises a pair of rollers 20 mounted on a frame 21 supported from an arm 22 carried by a slide 23, supported in guides 24, secured to one of the frames of London, England, a

, 2,775,451 Patented Dec. 25, p 1956 ice 2 the machine. The slide 23 is slotted at 25 to receive a pin 26 carried by an arm 27 pivotally supported, at 28, from frame 10 and connected by a link 29 with a crank pin 30 on a gear 31 which is driven by the handle 9. The frame 21 is pivotally supported on the arm22 so that the weight of the rollers and the frame hold the rollers in engagement with the topmost sheet of the stack of paper 13. The rollers 20 incorporate a oneway'clutch device whereby movement of the arm 22 away from the lower cylinder 17 permits the rollers 20 to run freely s over the stack of paper, while movement in the-opposite direction prevents rotation of the rollers,,.which,

being faced with rubber or the like, frietionally engage the topmost sheet. The rollers and frame then constitute a rigid link hich is pushed against the stackand carries the topmost sheet towards the bottom cylinder 17. A manual lever 32 is provided to disengage the pin 26 from the slot 25 to interrupt the feed drive when required.

As shown in Figure 2 a support 19 is provided to engage opposite edges of the stack 13. The support comprises a frame 35 having a flange 36 through which passes a bolt 37 to engage a nut element beneath the platform 12 so that the support 19 may be adjusted as required across the platform. As shown in Figure 3, the bolt 37 passes through a transverse slot 38 in the platform 12 to engage a nut element beneath the platform.

The support 19 comprises a rubber or the like pad 39-which in the particular construction being described has a corrugted face-secured, as by bonding or otherwise to a plate 40 which in turn is attached to a plate 41 having a vertical channel 42 stamped or otherwise formed in it. The portion 42 constitutes the cam follower pre viously referred to and for convenience the plate 41 will be referred to as the follower plate. The

plates

40, 41 are bolted together, at 43, and the follower plate 41 carries rearwardly projecting pins 44 which pass through guides 45 secured to' the frame 35 (see Figure 5). Mounted on the pins 44 are springs 46 which retract the pad 39 to behind the face 47 of the frame 35. A channel member 48 having a pair of finger pieces 49 is slidably mounted on link 50 of frame 35, the channel being slotted, as at 51 (Figure 3) to accommodate the guides 45. Each side element 52 of member 48 is formed with a cam face 53 to engage the portion 42 and, as shown in Figure 4, lengthwise adjustent of the member 48 adjusts face 43 along follower 42 thereby to vary the extent of which the pad 39 projects from the surface 47. It will be evident from Figure 5 that the cam surfaces engage the portion 42 of the follower plate at the upper and lower marginal regions of said plate so that the force of the cams on the pad is substantially uniform over the height of the pad and consequently the pressure of the pad on the edge of the stack is also uniform.

Referring to Figure 3, it will be observed that the pad 39 has a downward extension 55 which passes through the slot 38 in the platform 12. It is therefore ensured that the extension 55 engages the edge of the lowermost sheet of the stack and that the edge support is effective in regulating the supply of the sheets from the stack down to the lowermost sheet.

A particular advantage of the arrangement described is that the edge supports are easily and rapidly adjustable and capable of fine adjustment, it being only necessary to release the bolts 37 for a rough adjustment of the edge supports across the platform and thereafter to push the slots 48 lengthwise for fine adjustment of the pad 39.

I claim:

1. An edge support for a paper stack comprising a frame, a flat substantially vertical pad to engage the edges of the stack, a rigid carrier to carry the pad on the frame for movement in a direction normal to the face of the pad and towards and away'frorn the edge of the stack, a-cam-and-follower device for the top and for the bottom of the carrier and common means for simultaneously actuating said devices so that they apply equal pressure to the top and bottom of the carrier-whereby the pressure of the pad on the edge of the stack is substantially uniform throughout the height of the pad.

2. An edge support as claimed in claim 1 in which the carrier comprises a sheet metal plate formed with a vertical channel which constitutes said follower, the cam comprises a channel-section slide the side elements of which form the cam faces to engage the vertical channel and the carrier is supported from the frame by a pair of guides for retraction on reciprocation of said slide, said guides being spaced lengthw'se of the channel-section slide and substantially centrally between theside elements thereof.

3. An edge support for a paper stack which rests on the upper surface of a slotted platform to which the support is attached, comprising a frame, a flat, substantially vertical pad to engage the edge of the stack, a downward extension of the pad to enter the slot in the platform, a member to carry the pad on the frame for movement in a direction normal to the face of the pad and towards and away from the edge of the stack, a cam-and-follower device for the top and for the bottom of the carrier member and common means for simultaneously actuating said devices so that they apply equal pressure to the top and bottom of the carrier member whereby the pressure of the pad on the edge of the stack is substantially uniform throughout the height of the pad.

References Cited in the file of this patent UNITED STATES PATENTS