US2147529A - Automatic sheet feeding mechanism for relief stamping machines - Google Patents

Description

Feb. 14, 1939. R. D. GIFFORD ,1

AUTOMATIC SHEET FEEDING MECHANISM FOR RELIEF STAMPING MACHINES 'Filed march so. 1938 4 Sheets-Sheet 1 jwvenfor RANDOLPH D. GIFFORD y Feb. 14, 1939. R GIFFORD 2,147,529

AUTOMATIC SHEET FEEDING MECHANISM FOR RELIEF STAMPING MACHINES Filed March 30, 1938 4 Sheets-Sheet 2 &

,l'flmenfor mmnotm n GIPFmD Feb. 14, 1939. WP-0RD 2,147,529

AUTOMATIC SHEET FEEDING MECHANISM FOH RELIEF STAMPING MACHINES Filed March so, 1958 4 Sheets-Sheet s Ina- 72302 RANDOLPH Dc GIFF OR!) BY 044W A'ITGRNEYB 1 Feb. 14, 1939. R. D. GIFFORD: 2,147,529

AUTOMATIC SHEET FEEDING MECHANISM FOR RELIEF STAMPING MACHINES Filed March 30, 1938 4 Sheets-Sheet 4 [14 van Z0 2 RANDOLPH D. GIFFORD ATT mums Patented Feb. 14, 1939 UNITED STATES PATENT OFFICE AUTOMATIC SHEET FEEDING MECHANISM FOR RELIEF STAMPING. MACHINES Application March 30, 1938, Serial No. 198,994 In Great Britain April 1, 1937 7 Claims.

This invention has reference to the machines technically known in the printing industry as relief stamping machines and is concerned more particularly with machines of the well known type wherein an engraved plate or die is mounted in a carriage which slide in guides on the frame of the machine for bringing the plate or die, face downwards, to the position in which the printing operation is effected by the co-operation with the die when in this position of a ram or plunger-which is raised to bring the sheet to be printed, which sheet is fed between the die and plunger, into contact with the die for the impressing operation, the plate or die in its motion to and from the printing position being subjected to the necessary inking and scraping or wiping operations in a manner well understood. For examples of such machines reference may be made to British patent specifications Nos. 174,436 and 310,073.

Heretofore the feeding of the sheets to such relief stamping machines has been effected by hand.

The present invention has for its object the provision of automatic sheet feeding mechanism for relief stamping machines of the type aforesaid, the said mechanism being simple in construction and efficient in operation and being attended with the further advantage that it can be readily applied to existing relief stamping machines without necessitating any material alterations thereto. 1

The invention consists of an automatic sheet feeding mechanism for relief stamping machines of the type aforesaid, said feed mechanism being characterised by the association of a positively actuated displaceable sheet gripping device which receives a sheet delivered singly from a pile by sucker feed or equivalent mechanism to an initial feeding position and progresses it from this position to the stamping or impressing position, and a positively actuated simultaneously displaceable sheet gripping device which subsequently transfers the impressed sheet from the stamping position to a delivery point.

The invention further resides in the hereinafter described details of construction and assembly or combination of parts constituting an automatic sheet feed mechanism for relief stamping machines of the type aforesaid and in the provision in conjunction therewith of means, also hereinafter described, serving, in the event of failure in the feeding of a sheet between the impression die and ram, automatically to put into operation the means ordinarily provided, and

usually operable by hand, for checking the motion of the member which in the normal working of the machine effects the lifting of the impression ram so as to prevent it from coming into its operative contact with the said ram, thus 5 avoiding the soiling of the ram which would, in the absence of a sheet, result from its direct contactwith the inked face of the die.

The invention will be further and more particularly described with reference to the accompanying drawings which illustrate its application to a relief stamping printingmachine constructed in accordance with the general practice for hand feeding so much only of the ordinary machine being shown as is necessary to the full appreciation of the mechanism constituting the present invention and its operation in the running of the machine.

Figure 1 is a front elevation the said figure showing at the left hand side thereof sucker feed mechanism of known type whereby the sheets from a stack are fed singly to the initial position in which they are correctly placed to come under the operation of the mechanism constituting the present invention. 1

Figure 2 is an elevation viewed from the right hand side of the machine.

Figure 3 is a similar elevation viewed from the left hand side, the sucker feed mechanism being omitted from both these figures in order to avoid confusion.

Figure 4 shows a plan of a portion of the mechanism detached, and

Figure 5 is a fragmentary portion of the same part in end elevation.

The same letters and numerals of reference indicate the same parts in the several figures.

The main framework of the ordinary machine is denoted generally by the reference A, and B denotes generally the sucker feed mechanism whereby the sheets from a stack C are delivered singly on to the feed table D and it will be appreciated that this sucker feed mechanism which differs in no essential respect from such mechanisms as ordinarily employed in connection with various types of printing machines forms no part of the present invention, and simply functions as means for feeding the sheets singly to the point at which they come under the operation of the mechanism constituting the invention.

The automatic feed mechanism constituting the present invention and whereby the sheets which are fed singly to the table D by the sucker mechanism B, are progressed through the printing machine from the said table D to a delivery 55 point such as a conveyor, indicated at E in Figure 1, at the opposite side of the machine, em-- bodies a member 'I hereinafter referred to as the slide mounted so as to be capable of a reciprocable horizontal motion in a guiding carrier 8 constituted by a preferably dovetail grooved bar adapted to be secured, as for example by brackets I3 and bolts 8 in suitable location on the front face of the framing A of the ordinary machine.

The reciprocation of the said slide 1, for the purpose hereinafter more particularly described, is effected in the desired synchrony with the usual motions of the carriage of the printing plate or die 9 and the co-acting ram ID by coupling the said slide I with the horizontal shaft II which shaft supports the lever members to which the carriage of the die 9 is connected and by the operation of which the die is brought to and removed from the printing position in a manner well understood.

This shaft I I partakes, in the ordinary operations of the machine, of a rocking or partial turning motion in its bearings on the framing A and this rocking motion is utilized for effecting the reciprocatory motions of the slide 1, convenient means for this purpose comprising an arm I2 mounted on the said shaft I I and acting under spring control on a rod I3 disposed transversely to the axis of the shaft II, the forward end of the said rod being pivotally connected to one arm of a bell-crank lever I4 mounted in a bearing bracket I5 provided in suitable location on the framing A, the second arm of the said bell-crank lever having pivotal connection with a link I6 connected to the shorter arm of a bent lever-like member I! turning on the fulcrum II projecting from the front face of the framing of the machine, the said lever I I being pivotally coupled at its other end by a rod I8 to a bracket I on the slide I.

The arm I2 on the shaft II may be keyed directly to the shaft, or alternatively it may be made free to turn thereon in which case it is provided, as shown, with an extension I2 which lies against a similar part I2 on a collar keyed to the shaft II and to which part I2 it can be locked bya screw pin I2, this alternative arrangement permitting, by the withdrawal of the screw pin I2 the machine to be run without operating the slide I and parts in connection therewith, that is to say, to run as an ordinary machine, which may be desirable for making ready purposes, or in the event of a breakdown in the automatic feed mechanism.

The said slide 1, which is shown in Figure l of the drawings in the extreme right hand position to which it can be brought in the carrier 8 by its operating lever I1, is furnished on its forwardly presented side with brackets 1 1 to which are respectively fixed the vertically disposed bars I9 and 20 which serve for the mounting on and connection with the slide I of the gripping devices I9 and 2!) which act in association with each other, as hereinafter described, .to effect the passing of the sheets operated on from the table D to the delivery point E, the said grippers I9 and 20 being hereinafter referred to respectively as the feed gripper and the delivery gripper.

The gripper carrying bars I9 and 20 are so disposed on the slide I and so relatively spaced apart from each other that when the said slide 1 has travelled from the position shown in Figure 1, inwardly to its other extreme position in the carrier 8, the feed gripper I9 is brought to the position in which it can grip the sheet which has been placed in readiness on the feed table D by the sucker feed mechanism B, and simultaneously the delivery gripper 20 is brought to a substantially central position relative to the die 9 for the gripping of the sheet which has already been brought by the feed gripper I9, on the previous outward motion of the slide I, to the printing position.

The feed and delivery grippers I9 26 are of the pincer type their lever-like gripping arms or fingers being pivoted on the lower ends of the bars I9 and 20, and their opening and closing motions being effected by the action on the heels or short arms thereof of a block 2I of square, or other suitable formation, which is rocked through a link 22, the links of the respective blocks being operated by the rods I 9' and 20 disposed and slidable in guides I9 and 20 on the bars I9 and 20.

These rods I9 and 20 are adapted for operation at the requisite times by a series of levers 23, 24, 25 and 26 which are actuated by cams 23 24 25 and 26 on a rotating cam shaft 21 supported in bearings in pedestals 8 provided on the upper side of the carrier 8, the disposition of these cams and levers being best seen in the plan view shown in Figure 4.

The cam actuated levers 23, 24, 25 and 26 are mounted and turn on the spindle 28 which may be carried by the pedestals 8, and the said levers are of a bell-crank-like formation the ends of the arms thereof on which the cams on the shaft 21 act being preferably furnished with rollers while their other and forwardly projecting ends are or may be provided with flattened parts or ear pieces 23*, 24 25 and 26* which lie in the plane which is traversed by the gripper rods I9 and 20 in the reciprocating motions of the slide I, and when, at the appropriate times, the traverse of the slide I brings the upper ends of the rods I9 and 20* into operative position relative to the cam actuated levers, the levers 23 and 25 will respectively act to depress the rod which is brought thereunder for effecting the closing of the gripper fingers, and the levers 24 and 25 will likewise at the appropriate time, and by their action respectively on the overhanging part I9 20 provided on the upper ends of the said rods I9 and 20 and which ends are preferably furnished with screw set pins I9 211 act to lift the said rods and thereby open the gripper fingers, and it will be appreciated that the setting of the cams on the cam shaft 25, and the levers actuated thereby, is so arranged that their operative action on the gripper controlling rods I9 and 20 is synchronized with the other operations of the machine.

The cam shaft 21 may be driven from an existing driven shaft 29 of the ordinary machine by the provision on the said shaft 29 of a sprocket 30 geared by the drivingchain 3| to a similar sprocket on the cam shaft.

The correct positioning of the sheets delivered to the feed table D by the sucker feed B, or equivalent mechanism, is effected by the provision at this end of the machine of side and back lay devices.

The side lay may be constituted by a pair of lever-like members 32, fulcrumed on a transverse spindle 33 one end of which has a bearing on the frame and its other end a bearing on the lower end of a bar 34 depending from the carrier 8, the operation of the said lay, for raising the sheet restraining downwardly bent ends of the lever-like members 32 out of the path of the sheet to be removed from the table, being effected at the requisite times by the action, on the rod 55 in connection with one of the lever-like members, of a lever 36 which comes under the operation of a cam on the cam shaft 21, the said lever 35 being fulcrumed on a spindle 28 mounted in the pedestals 8 hereinbefore referred to on the carrier 8.

The back lay 31, which is of known type, is mounted on the frame of the machine so that its acting front end is in proper location relative to the table D and the requisite sliding movements of the said back lay may be effected through the medium of two bell-crank levers 38 and 39 fulcrumed on the main framing and interconnected by the rod 40, the lever 38 being in operative connection with the lay and the lever 39 coming under the action of a cam 4| on the rotating shaft 29 from which the cam shaft 2'! is driven.

The sheet which is taken from the table D by the feed gripper m is supported in its passage to the impression position and thence to the delivery point E by a bed plate 42 which may be constituted by a plate of steel suitably gapped to permit the upper end of the ram to rise therethrough, the said plate being supported along its front and rear edges by the longitudinal bars it carried by brackets 44 on the main frame and in order to prevent the leading edge of the sheet, which sheet is indicated by the dotted line X in Figures 2 and 3, from waving upwardly ribbons 45 preferably of strip-steel and supported from the frame by brackets such as 46 may be provided, the said ribbons 45 being disposed slightly above and extending along the front and rear edges of the bed plate 42.

A dabber finger or rod 41 may be provided to hold the positioned sheet against the table D until the said sheet is gripped by the feed gripper W the said dabber finger 41 being operated by the connection of its upper end to a lever 4! fulcrumed on the aforementioned spindle 28 and actuated by a cam on the cam shaft 21, and a second and similarly operated dabber 48 may be provided for holding the sheet when on the bed plate 42.

The action of the mechanism thus far described is briefly as follows:-

When the shaft II has in the ordinary running of the machine turned to the position in which the arm [2 is rocked to the position seen in the drawings the die 9 will be in position for the impression operation and at this moment the slide 7 is at the end of its outward stroke in the carrier 8, the feed gripper bar I9 then being at the centre of the machine and simultaneously, or practically so, the feed gripper W has been opened by the action on the lever 24 of the cam 24 and the dabber finger 4 8 depressed by operation on the lever 48 of the cam a t so that if a sheet has been brought from the bed D to this position by the previous operation of the machine it is released, impressed and held by the dabber practically simultaneously.

When the feed gripper I9 is in this position the associated delivery gripper 20 has been brought by its bar 20 to the delivery point E and if a sheet has been on the previous motion of the gripper in the inward direction picked up at the impression point it is now released at the delivery point, the gripper 20 being opened at the requisite moment by the action on the lever 26 of the cam 26*.

When the shaft II is rocked in the reverse direction to withdraw the die from the impression point, the inward motion of the slide 1 thereby brings the feed gripper 19 to the bed D for picking up the next sheet to be operated on, which sheet has been deposited in readiness and correctly laid on the bed by the operation of the lays already described and held by the dabber 4'! to the bed D pending removal therefrom by the gripper Ill which is closed on the sheet by the action of the cam 23 on lever 23 at the appropriate moment, and at the same time the associated gripper 20 has been brought to the central position and closed under the action of the cam 25 on the lever 25, on the impressed sheet waiting removal from this position,

It will be appreciated that the cams on the shaft 21 and the parts actuated thereby are so disposed and timed to operate that the sheets are fed automatically through the machine without strain on or damage to the sheets.

Machines of the type to which the automatic feed mechanism above described is applied ordinarily embody means, actuated by the operator, whereby, without stopping the running of the machine, the lifting of the ram in into contact with the die or impression plate 9 can be checked when the operator is not feeding sheets to the machine thus avoiding the soiling of the ram by coming into contact with the inked die or plate. The said means ordinarily comprise a trip finger 49 pivoted adjacent the upper end of an arm 50 mounted on the spindle 5| on which the arm 52, linked to and exercising control on the motion of the member 53 of the toggle mechanism, turns, the said trip finger being under the control of a lever 54 fulcrumed on the arm 50 and which is rocked by a rod 55, the lower end whereof has a bearing on the arm 56 of a counterpoised lever fulcrumed on the frame. The said rod 55 partakes of an upward motion when the arm 52 is moving forwardly to bring the toggle member 53 into the operative position relative to the part I of the ram [0 on which it bears to raise the said ram to the impressing position, the upward movement of the rod 55 turning the lever 54 to such position as will permit the finger 49 to turn out of the path of the forwardly moving arm 52, and thus allow the toggle member 53 to come into full operative effect on the ram Hi. When however it is desired to avoid the lifting of the ram without stopping the machine a pawl 58 mounted on the upper end of the arm 50 above the finger 49 is so moved, by the turning down of its operating handle 58 as to bring the pawl into a locking engagement with a projection 49 on the finger 49 which is thus maintained in a position in which it will engage with the shoulder 52 on the upper end of the arm 52 thus arresting the forward movement of the said arm and through its link connection with the toggle member 53 turning the said member in the direction Which will prevent it from coming into operative bearing on the ram I0.

Means whereby this check mechanism can be brought automatically into operation in the event of the automatic sheet feeding mechanism hereinbefore described failing to feed a sheet, are comprised in the present invention said means being operable from the cam shaft 2'! and embodying the provision of a pair of needles 59 such as are customarily employed in connection with check mechanisms in paper sheet feeding m chines, the said needles being carried by arms 60 on a spindle 6| disposed transversely across the bed D and supported in bearings in brackets fixed to the frame of the machine, the free ends of the said needles resting, when a sheet of paper is fed on to the bed, on the upper surface of the said sheet but when no sheet is delivered, the said ends rest on the bed and can engage with depressions 62 formed therein.

Ihe spindle 6| has an arm 62 connected by the rod 63 to a lever 64 on the spindle 28 which lever is rocked by the action of a cam 64 on the cam shaft 21, thereby effecting a rocking of the needle spindle 6| and giving to the needles a slight to-and-fro motion over the surface of the sheet of paper when a sheet is on the bed D. When however no sheet is present on the bed the needle ends drop into engagement with the aforesaid depressions 62 on the bed and arrest the rocking of the spindle 6| and, through the rod 63, of the lever 64. Connected to the end of the said lever 64 is a wire cable 65 which passes therefrom over a series of guide pulleys 66 to a connection with the arm 61 depending from the spindle 68 which extends across the lower front edge of the framing and has bearings in the opposite sides thereof. Mounted on the spindle 68 is a weighted arm fil which co-operates with the arm 61 in tending to maintain the cable 65 taut.

So long as sheets are fed on to the bed D the needles 59 move freely and the end of the lever 64 is moved downward on each revolution of the cam shaft 21 thus slackening the cable and pe mitting the turning of the spindle 68 under the action of the weighted arm 61 This turning of the spindle 68 lifts the rod 55, through the action thereon of the bracket 56 which is carried by the spindle 68, with the result that the check finger 49 turns to a non-acting position relative to the arm 52, but when no sheet is delivered to the bed D the free forward motion of the needles 59 is arrested by the engagement of their ends with the depressions 62 in the bed the turning of the needle spindle 6| is prevented, and consequently the rod 63 which connects the spindle 6| with the lever 64, holds the said lever against a downward turning motion with the result that the cable 65 is preserved taut, and prevents the turning of the spindle 68 which is necessary for the lifting of the rod 55 of the check mechanism, and thus the lever 54 which acts on the check finger and is operated by the rod 55, maintains the check finger 49 turned into the path of the shouldered upper end of the arm 52, thereby preventing the toggle member 53 coming into operation on the ram.

It will be appreciated that when the machine is running on automatic feed the handle 58 remains turned to the position in which the pawl 56 is out of contact with the projections 49 on the check finger 49.

What I claim is:--

1. An automatic sheet feed mechanism for use in connection with relief stamping machines of the type hereinbefore referred to, said sheet feed mechanism embodying in combination, a slide having a plurality of sheet gripping devices mounted thereon, a carrier capable of being fixed to the frame of the stamping machine and supporting said slide for horizontal reciprocatory motion, lever and link means adapted to be connected to a driven shaft of the stamping machine for operating said slide, a cam shaft extending longitudinally over the slide carrier and having means for connecting it to a driven shaft of the machine to be driven continuously therefrom, a plurality of cams on the said cam shaft, lever members fulcrumed adjacent the cam shaft and rockable by said cams, and means having connections with the reciprocable gripping devices and operable by said lever members to effect at the requisite times the opening or closing of the said devices.

2. Automatic sheet feed mechanism in accordance with claim 1, including a side lay device embodying a spindle having pivotal members fulcrumed thereon, one end of said spindle having a bearing in a bar depending from the carrier of the reciprocable slide, and a rod having a connection with a lever arm fulcrumed adjacent the cam shaft and actuated by a cam on the said cam shaft for operating said pivotal members.

3. Automatic sheet feeding mechanism as claimed in claim 1, including a back lay mounted on the side frame of the machine, and operating means therefor embodying two interconnected bell-crank levers fulcrumed on the side frame of the machine, one of the said levers having operative connection with the back lay and the other being operable by a cam on a driven shaft of the machine.

4. Automatic sheet feed mechanism in accordance with claim 1, including dabber fingers, and lever members fulcrumed adjacent the cam shaft over the carrier, and operable by cams on the said cam shaft to control said fingers.

5. Automatic sheet feed mechanism in accordance with claim 1, wherein the carrier for the reciprocable slide is provided on its upper side with pedestals having bearings for the cam shaft and carrying parallel rods constituting the fulcrums for the lever members provided thereon and operable by the cams on the cam shaft.

6. Automatic sheet feed mechanism in accordance with claim 1, including a gapped bed plate supported on longitudinal bar members carried by brackets provided on the side framing of the machine, and a plurality of longitudinally extending metallic ribbons suitably supported on the side framing of the machine and disposed over said bed plate.

7. Automatic sheet feed mechanism claimed in claim 1, for use in conjunction with relief stamping machines of the type having a toggle ram, toggle check mechanism and a trip finger, including means for effecting automatically the bringing into operation of the check mechanism without stopping the running of the machine, said means embodying a cable having one end thereof connected to a rockable member, a rod on which said rockable member is adapted to act and which controls the operation of the trip finger of the toggle check mechanism, a lever to which the other end of said cable is connected and-operable by a cam on the cam shaft of the automatic sheet feed mechanism, and a rockable spindle coupled with said lever and located over the feed bed and carrying needles the free ends whereof move over the surface of the sheet when a sheet is on the bed, but which needle ends in the event of failure in the sheet feed engage with depressions in the bed thereby arresting the rocking of said rockable spindle and preventing the turning of the lever coupled therewith and which controls the motions of the cable which interconnects the said lever with the mechanism controlling the toggle check mechanism.

RANDOLPH DOUGLAS GIFFORD.

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