US3501988A - Guillotine-type paper cutter - Google Patents

Description

D. A. MQRELLI GUILLOTINE-TYPE PAPER CUTTER March 24, 1970 14 Sheets-Sheet 1 Filed May 31, 1966 [ML/EN roe .Dwo A. Maze-Lu Haze/s, Mac/. 19063511. #KEQN March 24, 1970 D. A. MORELLI GUILLOTINE-TYPE PAPER CUTTER l4 Sheets-Sheet 2 Filed May 31, 1966 W9 llvu minim [/ws/v roe. Dave H. M oeELL/ 55 #15 HTTORNEYS.

Haze/s, K/ezw, Puss-E44 fksmv March 24, 1970 D. A. MORELLI 3,501,988

GUILLOTINE-TYPE PAPER CUTTER Filed May 31, 1966 14 Sheets-Sheet 5 8V HIS flrroRNE. flame/s, K 150 Pass #KEZN March 24, 1970 D. A. MORELLI GUILLOTINE-TYPE PAPER CUTTER 14 Sheets-Sheet 4 Filed May 51, 1966 Maze/s, K/ECl-l, Russel; f KERN March 24, 1970 D. A. MORELLI GUILLOTINE-TYPE PAPER CUTTER 14 Sheets-Sheet 5 Filed May 31, 1966 lkvs/vroe. D/No H. Mala-Lu 8? 1.0.9 nrroezvsw ffiwe/s, Mac, Fuss-51.1. KERN March 24, 1970 D. A. MORELLI GUILLOTINE-TYPE PAPER CUTTER l4 Sheets-Sheet 6 Filed May 31, 1966 .ZM/E/v r02 .0010 H. MoeELL/ Hue/a: K/ECH, Bussaz. ,5 KEEN March 24, 1970 D. A. MORELLI GUILLOTINE-TYPE PAPER CUTTER 14 Sheets-Sheet 7 Filed May 31, 1966 f/vvElw-ae. 17mm H. MOEELL/ 8? 1/15 QTTOQ/VEFQR Haze/s, K504, lei/$67511. #KEQN March 24, 1970 0.. A. MORELLI GUILLOTINE-TYPE PAPER CUTTER l4 Sheets-Sheet 8 Filed May 31, 1966 fivvE/vroe. D/No H. Mama.

8? ux: ATTORNEPS.

Mme/s K/EC/l, Ems-$51.1. f KEEN March 24, 1970 D. A. MORELLI GUILLOTINE-TYPE PAPER CUTTER 14 Sheets-Sheet 9 Filed May 31, 1966 IN VEN 7'02 DINO A M ORELL/ 8V 4/: nrroeaews.

flake/s, Macy, 203x541. {Ks/2N March 24, 1970 D. A. MORELLI GUILLOTINE-TYPE PAPER CUTTER 14 Sheets-Sheet 10 Filed May 31, 1966 Fa. I].

, i I w III 85 A/IS DTTOfA/EFS- Anems, Meal, fuss? KEe/v D. A. MORELLI GUILLOTINE-TYPE PAPER CUTTER March 24, 1970 14 Sheets-Sheet 12 Filed May 31, 1966 I/vvE/v roe. Dwo H. 114025441 A nee/s, K/Ecw, 20:35 45652! March 24, 1970 n. A. MORELLI GUILLOTINE-TYPE PAPER CUTTER 14 Sheets-Sheet 15 Filed May 31, 1966 fuvewroe. .Dnvo .Q. MORELL/ 8? A: HTTORNEVS.

l/aee/s, K1504 20.9.9541. #1 652 United States Patent 3,501,988 GUILLOTINE-TYPE PAPER CUTTER Dino A. Morelli, Pasadena, Calif., assignor to California Institute Research Foundation, Pasadena, Calif., a corporation of California Filed May 31, 1966, Ser. No. 554,029 Int. Cl. P26d 5/12 US. Cl. 83-171 16 Claims ABSTRACT OF THE DISCLOSURE A paper cutter of the guillotine type which, for a given lift-size capacity, is considerably smaller and lighter than prior paper cutters of this type and which has a low profile so that the operator, from his station at the front of the machine, can readily observe the lift of paper and the operation of components, such as the backstop, rearwardly of the knife and clamp.

The paper cutter is hydraulically powered and all hydraulic components are located below the table to prevent contamination of the upper surface of the table with hydraulic fluid, the same being true of all of the lubricating systems. The knife bar is guided at its ends by laterally sloping ramps which resist only downward forces acting on the knife bar, so that the knife bar can disengage the ramps in the event that the knife encounters an obstruction. The knife-bar drive means includes a yieldable hold-down means normally maintaining the knife bar on the ramps. The ramps are upturned at their lower ends to decelerate the knife bar at the lower end of its stroke.

The present invention relates in general to paper cutters and, more particularly, to a commercial paper cutter of the guillotine type especially suitable for use by printers, stationers, or the like, to cut lifts of paper into stacks of rectangular sheets of smaller sizes. However, various features of the invention may be embodied in other apparatuses, such as industrial paper cutters, or, more generally, machines for performing various predetermined operations on workpieces.

As background, the invention contemplates a paper cutter of the type which includes: a table for supporting a lift of paper to be cut; a guillotine-type knife above and extending laterally across the table and movable downwardly and laterally through the lift of paper to cut same with a shearing action; means for guiding the knife along a laterally sloping path to achieve the desired shearing action; means for driving the knife along its laterally sloping path; a backstop and a fence respectively engagea-ble with rear and side edges of the lift of paper to properly orient the lift relative to the plane of cut, the backstop being above and extending laterally across the table and normally being perpendicular to the table and parallel to the plane of cut, and the fence projecting above and extending along one side edge of the table and normally being perpendicular to the table and to the plane of cut; backstop drive means for advancing the backstop forwardly toward the plane of cut to advance successive portions of the lift of paper into positions to be sheared by the knife; means for guiding the backstop along its fore-andaft, longitudinal path; a clamp engageable with the lift of paper adjacent and rearwardly of the knife to prevent the shearing action of the knife from disturbing the uncut portion of the lift; means for guiding the clamp vertically into and out of engagement with the lift of paper; and means for driving the clamp.

As a general statement of the objects of the invention, the primary object is to provide a paper cutter of the foregoing type which is an improvement in various re spects on prior paper cutters of the same type.

3,501,988 Patented Mar. 24, 1970 'ice More particularly, general objects of the invention are to provide a paper cutter of the guillotine type which, for a give lift-size capacity, is considerably smaller and lighter than prior paper cutters of this type, thereby requiring significantly less floor space and, in most instances, requiring no special footings, or the like. For example, the invention has been embodied in a paper cutter for 42-inch by 4-inch lifts which weighs less than 3,000 pounds, as compared to prior paper cutters of the same size weighing as much as 12,000 pounds, and which requires less floor space than prior machines of the same size.

Another general object of the invention is to provide a paper cutter having a low profile so that the operator, from his station at the front of the machine, can readily observe the lift of paper and the operation of components, such as the backstop, rearwardly of the knife and clamp. More particularly, another object in this connection is to provide a paper cutter wherein the space above the knife and clamp is completely unobstructed, there being no yoke, or the like, in this region to raise the profile of the machine.

Still another general and extermely important object of the invention is to provide a paper cutter wherein all of the major components, i.e., the backstop, the knife and the clamp, are fluid driven, and specifically hydraulically driven. With this construction, various mechanical driving elements characteristic of prior machines, such as flywheels, clutches, lead screws, gear trains, and the like, are all eliminated, which is an important feature.

Another general object of importance is to provide a paper cutter which includes a floor-engaging base carrying the table, the knife, the clamp, the knife drive means and the clamp drive means, the plane of cut and the clamping zone being directly above the base so that cutting and clamping forces are transmitted directly to the base. The base supports an intermediate lateral zone of the table adjacent the front edge thereof so that the major portion of the weight of the table, and components carried thereby, is transmitted directly to the base. Consequently, it is merely necessary to provide a small auxiliary support for the rear edge of the table, which auxiliary support may be connected to the base, or engage the floor.

The base is preferably an extremely rigid structure capable of being secured to the floor at only two laterally-spaced points, the auxiliary supporting means for the rear edge of the table engaging the floor at a third point spaced rearwardly from the base in the event that it is not connected directly to the base. With such a threepoint support, the machine is unaffected by any uneven settling of the floor or footings on which it is mounted.

Still another object in connection with the base is to utilize it as a reservoir for the hydraulic fluid employed to operate the backstop, knife and clamp drive means. Preferably, the fluid motors incorporated in at least some of the drive means are located within the base so that any leakage therefrom is discharged directly into the reservoir, which is a feature of the invention.

Another object of the invention is to provide a hydraulically-powered paper cutter wherein all of the hydraulic components are located below the table to eliminate any possibility of contamination of the upper surface of the table with hydraulic fluid. Another object in this connection is to locate all lubricating systems below or at points spaced laterally from the table to avoid lubricant contamination of the upper surface of the table.

An important object of the invention is to provide means for locking hydraulic fluid in the knife drive means when the knife drive means is not in operation so that the knife can descend only slowly in the event of leakage of hydraulic fluid from the knife drive means. This minirnizes any possibility of injury to the operator in the event of accidental descent of the knife.

The invention contemplates mounting the laterally-extending guillotine-type blade or knife on a laterally-extending knife bar the ends of which are guided upwardly and downwardly along laterally sloping, parallel paths. A basic object of the invention in this connection is to provide a knife-bar guide means capable of resisting only downward forces acting on the knife bar, and incapable of resisting upward forces acting thereon. With this construction, the knife bar can disengage its guide means in the event that the knife encounters an obstruction, thereby eliminating any necessity for any separate overload device.

Another object of the invention is to provide a paper cutter wherein the base includes laterally sloping, parallel rams above table level on opposite sides of the table, and to provide the ends of the knife bar with ramp followers respectively engaging the ramps and movable upwardly and downwardly therealong to raise and lower the knife bar. A related object is to provide two such ramps on each side of the table in longitudinally spaced relation, the ends of the knife bar being received between the longitudinally spaced ramps of the respective pairs so that such ramps act as gibs resisting any forces applied to the knife bar longitudinally of the table.

A further and important object of the invention is to provide a hydraulic knife-bar drive means, below the table, which includes a hydraulic knife-bar drive motor of the reciprocating type oriented substantially parallel to the ramps and connected to one end of the knife bar, and which includes yieldable knife-bar hold-down means connected to the other end of the knife bar. With this construction, the knife-bar drive motor applies a cutting force to one end of the knife bar substantially in the direction of knife-bar movement, the knife-bar drive motor being inclined at a slightly greater angle than the ramps to apply a hold-down force to the corresponding knifebar end. The yieldable hold-down means connected to the other end of the knife bar normally holds the ramp followers at such other end of the knife bar on the corresponding ramps, but permits such other end of the knife bar to rise in the event that the blade encounters an obstruction, which is an important feature. A related object is to provide a hold-down means which applies a holddown force approximately proportional to the cutting force applied by the knife-bar drive motor.

An additional object of the invention is to provide th knife-bar ramps with arcuate valleys at their lower ends for decelerating both horizontal and vertical motion of the knife bar at the lower end of its stroke. With this construction, the knife bar can be driven at full speed until it has completed its out through the lift of paper.

Another object of the invention is to provide the table, in the plane of cut, with a laterally extending groove containing a repairable cutting stick penetrable by the cutting edge of the blade at the bottom of its stroke. More particularly, an object is to form the cutting stick of a material capable of being smoothed, by the application of heat, or otherwise. Still more specifically, an object is to make the cutting stick of a heat softenable material having heating means embedded therein.

Yet another object of the invention is to provide the guillotine-type knife with back clearance between the knife and the plane of the cut through the lift of paper. With this construction, forward forces on the front gibs during the cutting stroke are minimized.

A further object of the invention is to provide a guillotine-type double-edged knife of diamond cross section one cutting edge of which is seated in a downwardly-facing, inverted, V-shaped groove in the knife bar to expose the other cutting edge. Another object in this connection is to secure the knife to the knife bar by means of laterally spaced, upwardly and forwardly sloping bolts threaded into the knife at their lower ends and having heads at their upper ends seated against the knife bar, the bolts being disposed in forwardly facing, upwardly and forwardly sloping channels in the front of the knife bar. With this construction, the knife may be removed from its V-shaped groove merely by loosening the bolts sufficiently to permit lateral withdrawal thereof from the bolt channels. Thus, the bolts serve as a means for handling the knife, which is an important feature.

Another object in the foregoing connection is to provide the bolts with a low spring rate and to provide them with a diameter which is small and a length which is large as compared to the cross sectional dimensions of the blade. With this bolt construction, once the bolts have been tensioned, they will hold the knife in its V-shaped groove in a positive manner even if cutting forces drive the knife farther into its groove.

It is conventional in paper cutters of the type under consideration to provide the clamp or clamp bar and the backstop with laterally spaced clamping and pushing fingers, respectively, which intermesh in the forwardmost position of the backstop to permit advancing the rear edge of the lift of paper as close as possible to the plane of cut prior to making the last cut through the lift. An object of the invention in this connection is to make the clamping fingers on the clamp bar laterally wider than the pushing fingers on the backstop to obtain a given area of clamping engagement with a minimum clamp-bar dimension longitudinally of the table. This construction minimizes waste at the rear edge of the lift of paper, which is an important feature.

An additional object of the invention is to provide a hydraulic clamp-bar drive means which includes an upright clamp-bar drive cylinder below the table, rearwardly of (or within) the base, and connected to the ends of the clamp bar. More particularly, an object in this connection is to provide clamp-bar guide means on the base at opposite sides of the table, a laterally-extending torquetransmitting member below the table and having cranks at its ends which are connected to the respective ends of the clamp bar, and means connecting the clamp-bar drive motor to the torque-transmitting member.

Still another object of the invention is to provide the clamp-bar drive motor with an adjustable stroke so that if the machine is used to cut lifts of paper of less than maximum height, it is unnecessary to move the clamp bar through its maximum stroke. This results in a considerable reduction in the time required to make a number of cuts in a low lift of paper.

A further object of the invention is to provide clampingforce control means responsive to the widths of the particular lift of paper being cut for applying to such lift a clamping force which is a function of its width. A related object is to provide such a clamping-force control means which may either be manually operated, or which automatically senses the width of the lift of paper and adjusts the clamping force accordingly.

It is essential that the backstop move longitudinally of the table along a path which is perpendicular to the plane of cut, and one of the most important objects of the invention is to achieve this result with a T-square backstop guide means located below the table and having a longitudinally extending leg which projects forwardly from the backstop and which is located under the front portion of the table when the backstop is in its forwardmost position. This construction achieves a very substantial reduction in the over-all length of the machine, as opposed to a construction wherein the longitudinallyextending leg of the T-square guide means projects rearwardly from the backstop. The end result is a considerable reduction in the floor space required by the machine, elimination of a slot in the table, and a considerable reduction in the weight of the machine, since it permits most of the weight of the machine to be carried by the base in the manner hereinbefore outlined.

Another and important objectin connection with the backstop guide means is to incorporate in the longitudinally-extending leg of the T-shaped backstop carrier a hydraulic motor of the reciprocating type, and to utilize in conjunction with such motor a motion multiplying means, e.g., a motion doubler, for producing a backstop stroke greater than, e.g., double, the stroke of the motor. With this construtcion, the longitudinally-extending leg of the carrier may be made short enough to be received between the backstop and the front edge of the table when the backstop is in its forwardmost position, without increasing the distance between the backstop and the front edge of the table beyond that required to handle normal stacks of sheets cut from the lift.

The T-shaped backstop carrier has a laterally extending cross bar located under the table and connected at its ends to the ends of the backstop above the table. An object in this connection is to provide connectors or connecting means, between the ends of the backstop and the ends of the cross bar of the T-shaped backstop carrier, which are movable along the side edges of the table and which are laterally thin. A related object is to run the connector at the fence end of the backstop in a laterally narrow slot between the fence and the corresponding edge of the table, such slot being sufficiently narrow that it does not interfere with proper support for the corresponding side edge of the lift of paper.

Still another important object of the invention is to provide an automatically-programmed paper cutter having a backstop programmer extending along one of the side edges of the table and having backstop control means on the backstop carrier and engageable with the backstop programmer to control the backstop drive means. With this construction, the paper cutter may be programmed to cut a lift of paper in a predetermined pattern automatically. A related object is to mount the backstop programmer on the fence and to mount the backstop control means on the-corresponding end of the cross bar of the backstop carrier. Still another object is to provide a backstop programmer which includes a capstan rotatable about a longitudinal axis and carrying circumferentially spaced, longitudinally extending, programming members selectively engageable by the backstop control means upon rotation of the capstan.

A further object of the invention is to provide a backstop control means which includes a backstop control valve in one of the fluid lines leading to the respective ends of the cylinder of the backstop drive motor. A related object is to provide means for manually adjusting the maximum opening of the backstop control valve to limit the backstop speed.

The foregoing objects, advantages, features and results of the present invention, together with various other objects, advantages, features and results thereof which will be obvious to those skilled in the art to which the invention relates, may be achieved with the exemplary embodiments of the invention described in detail hereinafter and illustrated in the accompanying drawings, in which:

FIG. 1 is a plan view on a reduced scale of a guillotinetype paper cutter of the invention with certain covers removed;

FIG. 2 is a front elevational view, partially in section, of the paper cutter;

FIG. 3 is a side elevational view, partially in section, of the paper cutter showing the left side thereof;

FIG. 4 is a rear elevational view, partially in section, of the paper cutter;

FIG. 5 is a transverse sectional view through the paper cutter which is taken along the arrowed line 55 of FIG. 3 and which shows the knife bar of the paper cutter in its upper position;

FIG. 6 is a view whhich is identical to FIG. 5 except that it shows the knife bar in its lower position;

FIGS. 7 and 8 are enlarged, fragmentary sectional views respectively taken along the arrowed lines 77 and 8-8 of FIG. 6 and showing a knife-bar guide means for guiding the ends of the knife bar upwardly and downwardly along laterally sloping, parallel paths;

FIGS. 9 and 10 are fragmentary sectional views respectively taken as indicated by the arrowed lines 99 and 1010 of FIG. 7 and showing details of the knife-bar guide means;

FIG. 11 is an enlarged, fragmentary sectional view taken as indicated by the arrowed line 11-11 of FIG. 6 and showing a knife-bar drive means of the invention;

FIG. 12 is an enlarged, fragmentary sectional view taken as indicated by the arrowed line 1212 of FIG. 6 and showing a knife bar and a clamp bar of the paper cutter in cross section;

FIG. 13 is a fragmentary sectional view duplicating a portion of FIG. 12 on an enlarged scale and showing a guillotine-type blade or knife of the paper cutter in cross section;

FIG. 14 is a fragmentary sectional view taken generally as indicated by the arrowed line 14-14 of FIG. 12, but showing a backstop of the paper cutter advanced nearly to its forwardmost position relative to the clamp bar;

FIG. 15 is a fragmentary isometric sectional view illustrating a repairable cutting stick of the invention and a method of repairing it;

FIG. 16 is a view similar to FIG. 15 but showing an alternative repairable cutting stick and means for repairing it;

FIG. 17 is an enlarged, fragmentary sectional view taken as indicated by the arrowed line 1717 of FIG. 4 and showing a clamp-bar drive means of the paper cutter;

FIG. 18 is a fragmentary sectional view duplicating a portion of FIG. 17 but showing various parts of the clamp-bar drive means in different relative positions;

FIG. 19 is an enlarged, fragmentary sectional view taken as indicated by the arrowed line 1919 of FIG. 6 and showing a backstop guide and drive means of the invention;

FIGS. 20, 21, 22 and 23 are fragmentary sectional views respectively taken as indicated by the arrowed lines 2020, 2121, 22-22 and 2323 of FIG. 19, and showing details of the backstop guide and drive means;

FIG. 24 is an enlarged, fragmentary sectional view taken as indicated by the arrowed line 2424 of FIG. 4 and illustrating a backstop programmer of the invention;

FIG. 25 is a transverse sectional view through the backstop programmer which is taken as indicated by the arrowed line 25-25 of FIG. 24;

FIG. 26 is an enlarged, fragmentary sectional view taken as indicated by the arrowed line 2626 of FIG. 2 and illustrating a backstop position-indicating and control means of the paper cutter of the invention;

FIG. 27 is a view taken as indicated by the arrowed line 2727 of FIG. 26;

FIG. 28 is a mirror image of an enlarged, fragmentary sectional view taken as indicated by the arrowed line 2828 of FIG. 26 and illustrating details of the backstop control means;

FIG. 29 is a diagrammatic view illustrating the hydraulic system of the paper cutter;

FIG. 30 is a fragmentary diagrammatic view illustrat ing an alternative for a portion of the hydraulic system of FIG. 29, and, more specifically, an alternative backstop control means;

FIG. 31 is a diagrammatic view of a manually-operated clamping-force control means for the clamp bar of the paper cutter; and

FIG. 32 is a fragmentary rear elevational view of the clamp bar of the paper cutter showing an automatic clamping-force control means.

GENERAL DESCRIPTION Throughout the drawings, the guillotine-type paper cutter of the invention is designated generally by the numeral and includes the following general components:

A supporting means or structure comprising a laterally extending base 102 engageable with a floor 103, a table 104 connected to the base adjacent but rearwardly of the front edge 106 of the table, and an auxiliary table support 108 located on the longitudinal centerline of the table and connected to the rear edge 110 thereof, such auxiliary support being shown as engaging the floor 103, but being connectible directly to the base as an alternative;

A knife bar v112 mounted on the base 102 and located above and extending laterally across the table 104, the knife bar being positioned directly above the base so that paper cutting forces are transmitted directly to the base;

A guillotine-type blade or knife 114 carried by the knife bar 112 and extending laterally across the table 104;

Knife-bar guide means 116 on the base 102 at opposite sides of the table 104, and on opposite ends of the knife bar 112, for guiding the knife bar upwardly and downwardly along a laterally sloping path, the knife-bar path sloping downwardly to the left in the particular construction illustrated;

Hydraulic knife-bar drive means 118 carried by the base 102 below the table 104, and connected to the ends of the knife bar 112, for moving the knife bar upwardly and downwardly along its laterally sloping path;

A clamp bar 120 located above and extending laterally across the table 104 adjacent and behind the knife bar 112 and adapted to clamp a lift of paper against the table as a lateral cut through the lift is made by the knife 1 14;

Clamp-bar mounting and guide means 122 carried by the base at opposite sides of the table 104 for guiding the clamp bar 120 upwardly and downwardly relative to the table;

Clamp-bar drive means 124 carried by the base 102 below the table 104 for moving the clamp bar 120 upwardly and downwardly relative to the table;

A backstop 1% extending laterally across the table 104 and slidable on the upper surface of the table be tween a rearward position adjacent the rear edge 110 of the table and a forward position adjacent the knife and clamp bars 112 and 120, the backstop being engageable with the rear edge of the lift of paper to advance successive portions of the lift to the operating station occupied by the knife and clamp bars;

T-square backstop guide means 128 located below the table 104 and connected to the ends of the backstop 126 along the side edges of the table for guiding the backstop longitudinally of the table between its rearward and forward positions;

Hydraulic backstop drive means 130 below the table 104 and incorporated in the T-square backstop guide means 128 for moving the backstop 126 longitudinally of the table 104 between its rearward and forward positions;

A fence 132 extending longitudinally of the table 104 along one side edge of the table, preferably the left side edge thereof, and engageable with the corresponding side edge of the lift of paper to guide the lift longitudinally of the table;

A backstop programmer 134 mounted on the fence 132 and extending along the corresponding side edge of the table 104; and

Backstop control means 136 movable with the backstop 126 and engageable with the backstop programmer to control the backstop drive means 130.

The foregoing general components of the paper cutter 100 of the invention will be considered in more detail hereinafter under corresponding headings.

Base 102 Except for the small fraction of the weight of the paper cutter 100 which is carried by the auxiliary support 108 in the particular construction illustrated, the entire weight of the machine is transmitted to the floor 103 through two laterally-spaced, floor-engaging feet 140 on the base, which feet may be secured to the floor by bolts 142, FIGS. and 6. As will be pointed out hereinafter, many of the components of the paper cutter are mounted directly on the base 102 so that the weights thereof are transmitted directly to the base, the weights of the remaining components being transmitted thereto indirectly through the table 104. Preferably, the base 102 is an extremely rigid casting so that it provides proper support for all of the components of the machine despite uneven settling of the floor 103, or the like.

In addition to supporting virtually the entire weight of the paper cutter 100, the base 102 is provided internally thereof with a reservoir 144 for the hydraulic fluid used to power such components as the knife-bar drive means 118, the clamp-bar drive means 124 and the backstop drive means 130. Thus, the base 102 serves a dual function. Additionally, as will be described later, various hydraulic components of the paper cutter 100 are mounted on the base 102 within or above the reservoir 144 formed thereby so that any leakage from such components is discharged directly into the reservoir, which is an important feature.

In addition to the foregoing structural features, the base 102 is provided on opposite sides of the table 104 with two integral, laterally spaced supports 146 for the knife-bar and clamp-bar guide means 116 and 122, such supports projecting upwardly above the upper surface of the table. These supports 146 are rigidly interconnected by the base 102 itself, thereby obviating any necessity for any interconnecting yoke, or the like, above the knife and clamp bars 112 and 120. Thus, the space above the knife and clamp bars 112 and and between the supports 146 is unobstructed to provide the paper cutter 100 with a low profile. Consequently, the operator of the paper cutter 100, from his station at the front of the machine, can readily observe the lift of paper on the table 104 rearwardly of the knife and clamp bars 112 and 120, and can readily observe the operation of such components as the backstop 126 which are located behind the knife and clamp bars. This low profile, and its attendant advantages, represent an important feature of the invention.

Table 104 The table 104 is essentially a rectangular plate having a plane upper surface. The table 104 is suitably stiffened both laterally and longitudinally by integral lateral and longitudinal stiffening ribs on its lower surface, which ribs will not be described in detail. The table 104 is suitably bolted to the base 102 at 147, FIG. 1, below the knife bar 112 so that the cutting forces, which are the major forces applied to the table, do not tend to alter the positional relationship between the table and the base. Lateral extensions 148 are secured to the table 104 forwardly of the base 102 to provide additional working areas to receive stacks of paper from the lift being cut.

Knife bar 112 and knife 114 Referring particularly to FIGS. 5, 12 and 13 of the drawings, the knife bar 112 is essentially a beam of sufficient length to span the space between the two supports 146 on the base 102 at opposite sides of the table 104. The knife bar 112 is provided in its lower edge with a downwardly-facing, inverted, V-shaped groove 150. The knife 114 is a guillotine-type double-edged knife of diamond cross section complementary to the V-shaped groove 150, As shown in FIGS. 12 and 13, the knife 114 is seated in the V-shaped groove 150 with one cutting edge 152 of the knife exposed and with the other disposed in a protective cavity 154 at the apex of the groove 150. As will be apparent, with this construction, cutting forces acting on the knife 114 merely serve to seat it more firmly in its V-shaped groove 150.

Preferably, the two halves of the knife 114 are hollow ground, as indicated at 156. This facilitates resharpening of the cutting edges 152 by minimizing the amount of material which must be removed.

An important feature of the invention is that each half of the knife 114 is provided, as best shown in FIG. 13, with back clearance 158 between the corresponding back plane 160 and the lift 162 being cut. The back clearance 158, which may be of the order of one degree, is important because it minimizes the forward reaction force applied to the knife bar 112 as the result of the interaction between the knife 114 and the lift 162 during the shearing operation.

Considering the manner in which the knife 114 is held in its V-shaped groove 150, and referring particularly to FIGS. and 12 of the drawings, the knife bar 112 is provided with an upwardly-and-forwardly sloping surface 164 terminating at its upper edge in an upwardly-andforwardly facing shoulder 166. Covering part of the top and front sides of the knife bar 112 is a clip 168 having a portion 170 complementary to and seated on the shoulder 166. Seated on the portion 170 of the clip 168 are the heads of long, slender bolts 172 which slope downwardly and rearwardly, parallel to the surface 164, and which are threaded at their lower ends into the knife 114, the hollow ground surfaces of the knife being generally parallel to the bolts 172. The surface 164 of the knife bar 112 is provided therein with laterally spaced, downwardly-and-rearwardly sloping channels 174 therein which receive the respective bolts 172.

It will be apparent that, with the foregoing construction, the knife 11 4 is held in its V-shaped groove 150 by tightening the bolts 172 to seat the heads thereof against the shoulder 166 on the knife bar 112, through the intervening portion 170 of the clip 168. In order to remove the knife 114, it is merely necessary to loosen the bolts 172 sufliciently to permit the portion 170 of the clip 168 to be slipped downwardly and forwardly off the shoulder 166 on the knife bar. Subsequently, the bolts 172 can be withdrawn downwardly and forwardly from their channels 174, whereupon the knife 112 can be removed from its V-shaped groove 150. The clip 168 may be used as a handle for removal and subsequent handling of the knife 114, thereby avoiding any necessity for handling the knife itself, which is an important feature. A similar procedure may be followed in installing the knife 114.

It will be noted that the holes in the knife 114 for the bolts 172 extend entirely through the knife so that the bolts can be threaded into such holes from either end thereof. This permits reversing the position of the knife so that the other cutting edge 152 thereon can be utilized. As will be apparent, this reversal of the bolt position can be accomplished with one of the hollow ground surfaces of the knife 114 lying flat on a suitable supporting surface, thereby avoiding any necessity for handling the knife itself during this operation.

Considering another important feature of the invention, the diameter of the bolts 172 is quite small as compared to the cross sectional dimensions of the knife 114, and the length of the bolts is large as compared thereto. More particularly, the diameter of the bolts 172 is but a fraction of the smallest cross sectional dimension of the knife 114, and the length of the bolts is at least double the largest cross sectional dimension of the knife. Additionally, the bolts 172 have a low spring rate which, coupled with their long length and small diameter, result in holding the knife 114 in its V-shaped groove 150 in a positive manner even if cutting forces drive the knife further into its groove. Thus, it is unnecessary to retighten the bolts 172 after the machine has been in operation for a time.

As shown in FIGS. 12, 13, 15 and 16, the table 104 is provided in its upper surface with a dovetail groove 176 in the plane of cut of the operative cutting edge 152 of the knife 114. The groove 176 contains a cutting stick 178 capable of being penetrated by the operative cutting edge 152 of the knife 114 at the lower end of the stroke of the knife bar 112, thereby providing sufiicient downward cutting edge travel to insure cutting the lowermost sheet of paper in the lift 162. An important feature of the invention is that the cutting stick 178 is repairable. One way of accomplishing this is to make the cutting stick 178 of an alloy which is heat softenable at a relatively low temperature. Thus, the cutting stick 178 can be repaired, i.e., provided with a smooth upper surface, by running a soldering iron 180, FIG. 15, or other heating device, over the upper surface of the cutting stick. FIG. 16 illustrates an alternative wherein the heat softenable cutting stick 178 has a suitable heating element 182, such as a resistance heating element, embedded therein. By energizing the heating element 182 sufficiently to melt the alloy of the cutting stick 178, it will automatically have its upper surface restored to a smooth surface. Other repairable cutting sticks formed of suitable plastic materials may also be used.

Knife-bar guide means 116 The knife bar 112 is guided along its laterally sloping path by laterally sloping, parallel ramps on the supports 146 at opposite sides of the table 104. Each support 146 is provided with two such ramps 190 spaced apart in the fore-and-aft or longitudinal direction, as shown in FIGS. 1, 7 and 8 of the drawings. The angle of inclination of the ramps 190, which preferably slope downwardly to the left, is such as to provide an optimum cutting angle for the knife 114, e.g., a cutting angle of the order of 20 to 25.

The knife bar 112 is provided at each end thereof with two ramp follower wheels 192 spaced apart in and rotatable about an axis extending in the fore-and-aft direction, as best shown in FIGS. 7 and 8. The wheels 192 are seated on and rollable along the respective ramps 190 to guide the knife bar 112 upwardly and downwardly along its laterally sloping path.

As best shown in FIGS. 7 and 8, the wheels 192 at each end of the knife bar 112 are mounted on a shaft 194 journalled in an eccentric sleeve 196 in a bore 198 through the corresponding knife-bar end, the eccentric sleeve being secured by a set screw 200, FIG. 9. As best shown in FIG. 10, each eccentric sleeve 196 is provided at one end thereof with flats 202 engageable by a wrench, not shown, for adjusting the angular position of such eccentric sleeve. With this construction, the angular posi tions of the eccentric sleeves 196 may be adjusted to raise or lower the knife bar 112 as required to obtain the desired penetration of the operative cutting edge 152 of the knife 114 into the cutting stick 178. For example, the adjustment provided by the eccentric sleeves 196 may be used to compensate for decreases in the spacings of the cutting edges 152 of the knife 114 due to repeated sharpenings.

As best shown in FIGS. 2 and 5, the ramps 190 are provided at their lower ends with upwardly concave, arcuate terminal portions or valleys 204. The valleys perform the important function of providing for overtravel of the knife bar 112 as it is decelerated at the lower end of its stroke. The fact that the knife bar 112 must go upwardly slightly as the wheels 192 traverse the valleys 204 increases the deceleration of the knife bar 112. Consequently, the knife bar 112 may be driven downwardly at full speed until the knife 114 has cut entirely through the lift of paper, the knife bar subsequently being decelerated as the wheels 192 thereon negotiate the valleys 204 at the lower ends of the ramps 190.

Referring particularly to FIGS. 7 and 8, the supports 146 on the base 102 at opposite sides of the table 104 comprise longitudinally spaced plates which provide each support with longitudinally spaced gibs 206 receiving the corresponding knife-bar end therebetween and restraining same against movement in the fore-and-aft direction. The upper edges of the plates forming the gibs 206 constitute the ramps 190. This construction provides a very compact and simple means for guiding the knife bar 112 along its 11 laterally sloping path while simultaneously restraining it against fore-and-aft movement.

The ends of the knife bar 112 are provided on the forward side of the knife bar with thrust bearings 208 respectively engageable with the front gibs 206 to resist forward forces on the knife bar resulting from the guillotine action of the knife 114. As previously pointed out, forward forces on the knife bar 112 are minimized by providing the knife 114 with the back clearance 158. The rear face of the knife bar 112 directly engages the rear gibs 206, no thrust bearings being necessary at these points because rearward forces on the knife bar are negligible.

The thrust bearings 208 are provided with bosses 210 which project rearwardly into and are suitably sealed relative to counterbores 212 in the respective ends of the knife bar 112, the counterbores 212 terminating in bores 214 through the rear face of the knife bar. Compression springs 216 in the counterbores 212 bias the thrust bearings 208 against the front gibs 206.

Considering the manner in which the gibs 206 are lubricated, each end face of the knife bar 112 is provided with an oil passage 218, FIG. 9, leading to the corresponding counterbore 212. The rear end of the corresponding bore 214 is provided with an oil-porous plug 220 through which oil in the corresponding counterbore 212 may seep to lubricate the corresponding rear gib 206. Each thrust bearing 208 is provided therein with an oilporous plug 222 through which oil may seep from the corresponding counterbore 212 to lubricate the corresponding front gib 206. This provides a very simple and direct lubricating system for the gibs 206. Also, it will be noted that since the supports 146 for the knife bar 112 are spaced laterally from the side edges of the table 104, it is impossible for any of the lubricating oil for the gibs 206 to contaminate the upper surface of the table.

As best shown in FIG. 6, the space between the longitudinally-spaced ramp-and-gib-forming portions of the right-hand support 146 communicates with the upper surface of the table 104 to provide a paper chute designated generally by the numeral 224. Small scraps of paper produced by the knife 114, as in making trim cuts in cutting cards, labels, or the like, may be discharged from the table 104 into a suitable waste-paper receptacle, not shown, through the paper chute 224.

The left-hand support 146 provides a wedge-shaped notch, not shown, to receive the knife 114 at the lower end of its stroke. If not prevented, paper scrap from the table 104 could pass through this notch and foul a part of the knife-bar drive means 118 to be described hereinafter. To prevent this, the invention provides a paper deflector 228, FIG. 6, movable upwardly and downwardly with the knife bar 112 and closing the wedge-shaped notch mentioned. To provide the proper motion for the paper deflector 228, it is mounted on a long arm 230, FIG. 3, pivotally connected to the rear end of the fence 132. A suitable spring, not shown, biases the paper deflector 228 upwardly against the sloping front surface of the knife 114 so that the paper deflector 228 moves upwardly and downwardly with the knife bar 112. In doing this, it constantly keeps the aforementioned wedge-shaped notch in the lefthand support 146 closed.

Knife-bar drive means 118 As will be apparent, the knife-bar guide means 116 resists only downward forces acting on the knife bar 112 and is incapable of resisting upward forces acting thereon. Such upward forces are resisted by the knife-bar drive means 118 in a manner which provides an automatic overload relieving system, as will be described subsequently in this section.

As best shown in FIGS. and 6 of the drawings, the knife-bar drive means 118 includes a hydraulic knife-bar drive motor 232 of the reciprocating type disposed within the base 102 so that any leakage therefrom discharges directly into the reservoir 144. The knife-bar drive motor 232 includes a cylinder 234 one end of which is anchored by means of a longitudinally-extending pin 236 spanning the interior of the base 102 and suitably secured to the front and rear walls of the base. Reciprocable in the cylinder 234 is a piston 238 having connnected thereto a piston rod 240 which projects from the opposite end of the cylinder. The outer end of the piston rod 240 is connected to the right-hand end of the knife bar 112 by a pin 242, as best shown in FIG. 7.

As will be apparent, extension and contraction of the knife-bar drive motor 232 respectively result in upward and downward movement of the knife bar 112 along its ramps 190. The knife-bar drive motor 232 is substantially parallel to the ramps 190, but is oriented at a slightly steeper angle so that it applies to the right-hand end of the knife bar 112 a force component acting to maintain the corresponding wheels 192 in engagement with the corresponding ramps 190. Thus, the knife-bar drive motor 232 restrains the right-hand end of the knife bar 112 against upward movement.

Referring to FIG. 11 of the drawings, the ends of the cylinder 234 and the corresponding ends of the piston 238 are formed to provide two dashpot means, each designated generally by the numeral 246, for decelerating the piston 238 and the knife bar 112 at the ends of their respective strokes. Additionally, the piston 238 carries elastomeric bumpers 248 respectively engageable with stops 250 at the ends of the cylinder 234. The elastomeric bumpers 248 supplement the decelerating actions of the dashpot means 246 to eliminate shock at the ends of the stroke of the knife bar 112.

The knife-bar drive means 118 includes yieldable, hydraulic, hold-down means 252 for restraining the lefthand end of the knife bar 112 against upward movement tending to disengage the left-hand wheels 192 from the left-hand ramps 190. However, the yieldability of the hold-down means 252 permits the left-hand end of the knife bar 112 to rise in the event of an overload, which may result from an excessively thick lift of paper, a dull cutting edge 152 on the knife 114, an obstruction, or the like. This is an important feature since it avoids any necessity for a separate system to protect against an overload on the knife 114.

Considering the knife-bar hold-down means 252 in more detail, it also includes a hydraulic motor 254 of the reciprocating type within the base 102. The knife-bar hold-down motor 254, as best shown in FIGS. 5, 6 and 1, includes a cylinder 256 connected at one end to the same pin 236 as the cylinder 234 of the knife-bar drive motor 232. Disposed in the cylinder 256 is a piston 258 having connected thereto a piston rod 260 projecting from the opposite end of the cylinder. A compression spring 262 encircling the piston rod 260 biases the piston 258 toward the anchored end of the cylinder 256. As shown in FIGS. 5 and 6, the free end of the piston rod 260 has connected thereto one end of a cable 264 which is trained under a pulley 266 carried by the base 102 and which has its other end connected to a pin 268 on the left-hand end of the knife bar 112, as best shown in FIG. 8. The cable 264 is suitability sealed between the pulley 266 and the hold-down motor 254 to prevent leakage of hydraulic fluid from the base 102 along the cable. (The purpose of the hereinbefore-described paper deflector 228 is to prevent paper scraps from fouling the cable 264 and pulley 266.)

The relative positions of the pulley 266 and the lefthand ramps are such that the left-hand end of the knife bar 112 moves up and down such ramps with very little extension and contraction of the hold-down motor 254. Thus, the hold-down piston 258 is subject to relatively little movement from the positions shown in FIGS. 5 and 6. The hold-down cylinder 256 is provided with a pressure inlet fitting 270 which applies hydraulic pressure to the hold-down piston 258 in a direction to tension the cable 264, this fitting being so located that it con-

Images