Abstract: A punch for removing material from lead frames has a substantially rectangular body with an array of grooves along one side and a step removed on one end from the side opposite the grooves to provide an array of punch teeth extending from the body of the punch. The grooves provide a means of reworking the punch to provide a new array of teeth, by machining away all or part of the teeth and then extending the step in the direction of the groove to provide substantially the original length for the individual teeth. By providing a punch with groove length several times the tooth length, the punch can be reworked several times before being discarded.

Abstract: An agricultural baler for making cylindrical bales of crop material having a sledge assembly moveable between bale starting and full bale positions. The sledge assembly includes a plurality of rollers which cooperate with an array of belts to define a bale forming chamber. A dispensing mechanism is provided for dispensing web material, such as net or the like, into the bale forming chamber whereupon it is wrapped circumferentially around a cylindrical package of crop material in the bale forming chamber. Included along the path of the net prior to being fed into the chamber is a severing assembly for cutting the net after it has been wrapped around the cylindrical hay package formed in the chamber. The net severing assembly includes a unique severing element that provides improved net cutting.

Abstract: A bagel slicer comprising a food holder having a receptacle for holding a bagel, and a blade holder with a blade, a handle and a pair of blade guarding walls. The food holder has a base and a pair of spaced vertical receptacle walls extending upwardly from the base forming a pair of opposed vertical slots. The blade holder has a handle, a pair of spaced transparent blade guarding walls surrounding and guided along the vertical walls of the food holder, and a blade having a pair of serrated cutting edges intersecting one another. The blade is arranged and dimensioned to ride in the vertical slots and to traverse the central part of the receptacle when the handle is vertically actuated to slice the food article. The bagel is held by a cradle which has blade protection lips to guard the blade cutting edge at the lower travel limit.

Abstract: A shingle cutting tool for cutting a shingle having a longitudinal edge, the shingle cutting tool making a cut across the shingle at a selectable angle transverse to the longitudinal edge thereof, the shingle cutting tool including a guide member, the guide member having a substantially upright surface for guiding the longitudinal edge of the shingle, and a cutting assembly, the cutting assembly being pivotally attached to the guide member and extending outward therefrom, the cutting assembly including a cutting base member, a cutting blade, the cutting blade having a cutting edge, the cutting edge opposing the base member, a reciprocating guide mechanism for guiding the cutting blade in a reciprocating fashion within a plane extending from the cutting base, and a pressure mechanism for exerting a pressure on the cutting blade to thereby bring the cutting edge into contact with the cutting base member.

Abstract: A guillotine-type cutter blade cuts sheets such as papers, metallic plates, etc. The cutter blade is provided at the back face with a flank which is inclined at an angle of 1.degree. to 7.degree. with respect to the moving direction of the cutter so as not to be in contact with the cut surface of the sheets, thereby preventing formation of a built-up edge.

Abstract: The subject of the invention is a device for simultaneous shearing of two sheet metal blanks comprising, for each sheet metal blank, an assembly formed, on the one hand, by a support member of the corresponding sheet metal blank comprising a rectilinear cutting edge and, on the other hand, by a movable cutter provided with a rectilinear cutting edge designed to interact with the cutting edge of the corresponding support member. The cutting edges of the two support members and cutters assemblies are situated in a same reference plane P and the support members extend on either side of the reference plane P. The invention applies to installations for welding by laser beam of two sheet metal blanks placed edge to edge.

Abstract: A saw blade retention system for retaining a saw blade to a reciprocating saw includes a shaft connected to the saw for reciprocation and having a slot for receiving the saw blade. The saw blade retention system also includes a chuck disposed about the shaft and having a slot aligned with the slot in the shaft in an unlocked position for allowing the saw blade to be disposed in the slot for the shaft. The saw blade retention system further includes a cam-type mechanism for allowing the chuck to rotate angularly relative to the saw blade and shaft to a locked position to prevent the saw blade from exiting the slots and for allowing the chuck to move axially relative to the shaft to prevent axial movement of the saw blade between the chuck and the shaft. Complementary inclined surfaces are provided on the blade and the chuck to center the blade relative to its intended path of reciprocation.

Abstract: A system for handling of cheese in the green state particularly directed for handling natural cheese types such as cheddar and colby in a manner so that they can be conveniently sub-divided and individually packaged, on the same day of manufacturing, into a variety of finished consumer and cheese market sized portions. The system includes the handling of green cheese immediately as it is formed through the processes of batch or continuous cheese making equipment and cheese towers to provide, preferably, 40 to 45 or other selected pound blocks of green cheese. The cheese blocks are immediately handled after forming to eliminate the normally utilized bulk block aging or curing systems. The green cheese blocks are selectively handled and may be placed into temporary bulk block pouches and packaged for future handling or are directed to trimming and cutting devices which will trim and cut the blocks into the consumer, market size units.

Abstract: As a cutter having first and second cutter blades is driven toward a molded ceiling consisting of a base material and a surface material which is attached to the base material in a stretched state, the surface material is first cut by the first cutter blade which is adapted to cut the molded ceiling at a position outside of a predetermined trimming or cutting position such that the trimmed or cut end of the surface material is inclined to have a flat triangular sectional shape. Then, the inclined end of the surface material is cut off together with an excess portion of the base material by means of the second cutter blade which is adapted to cut the molded ceiling at the predetermined trimming or cutting position.

Abstract: A method and apparatus for practicing the method by which a reciprocating saw may be utilized to cut within the edges of a panel of material without the necessity of providing a pilot hole or the like for the saw blade, wherein the saw blade is configured in such manner as to taper at the end not attached to the saw motor in order to come to a point and wherein a knife edge is supplied along the edges of said tapered portion of said saw blade, wherein the saw blade at its pointed and tapered end is allowed to cut through the panel of material being sawed with the sawing action commencing immediately after full penetration of the blade through the material.

Abstract: A cutting machine for cutting elongated, extruded plastic articles includes a cutter assembly composed of a pair of side-by-side, plate-like cutting die bushings having a transverse article opening formed therethrough configured and dimensioned to accommodate the passage and guidance of an elongated extruded plastic article therethrough, and a thin, generally planar cutting blade having a cutting edge. The blade is supportable for reciprocable movement between the cutting die bushings for movement between an operative position in which the blade moves across the article opening so as to cut an article disposed therein and an inoperative position in which the blade is displaced from the article opening. The blade is supported for reciprocable movement by at least one support finger disposed on each side of the blade which serves to prevent buckling of the blade.

Abstract: A station (10) for cutting sheets of wood (13), and in particular for cutting packages of sheets, includes a first device (12) for positioning a package of sheets under a first cutter (15) so as to separate parts of the package sequentially. A further device (14) takes the cut part and sends it to a second cutter (17) for sequentially cutting the part along a second direction so as to obtain another division in subparts sequentially and selectively conveyed outside the station. Electronic controls are used to manage operation of the cutters and the positioning and taking devices for performing the cuts in accordance with a previously set grid of cuts.

Abstract: A web severing device for providing a smooth severed edge on a moving web. The device includes a support member and a plurality of independent blade sections mounted on the support member at substantially a 45.degree. angle with respect thereto. In one embodiment, a forward portion of each of the blade sections is angled toward a center of the support member whereas in a second embodiment, the blades are alternately angled toward and away from the center of the support member. In all embodiments, the support member is selectively released toward the web, and the plurality of blade sections simultaneously engage with the web to sever the same.

Abstract: This invention relates to saw blades for use in reciprocating hand-manipulated saws. The blades of the invention have a straight, untoothed edge lying parallel to the longitudinal axis of the blade and a toothed edge wherein at least 30% of the toothed edge is curved.

Abstract: A sheet cutter comprises a fixed cutting member; a movable cutting member whose cutting edge slopes so that the movable cutting member has a V-shaped extension and/or notch; and a control member for controlling the stroke of the movable cutting member, whereby the movable cutting member is moved to overlap with the fixed cutting member to shear a sheet at a predetermined portion thereof.

Abstract: In the first embodiment, the distal end of a reciprocating plunger of a power saw includes a longitudinally extending cavity receiving a block-like wedge member. A planar wall of the cavity and a planar face of the wedge member are arranged for substantial coextensive engagement with respective opposed faces of the saw blade. A spring in the cavity engages the wedge member for urging the same outwardly of the cavity. A pin extends through the wedge and has its opposite ends received in slots in opposed walls of the plunger. These slots are inclined with respect to the longitudinal axis of the plunger and cooperate with the pin to form a cam to urge the planar surfaces into clamping engagement with the blade under the influence of the spring. The blade may be released by forcing the wedge inwardly of the cavity under finger pressure. In a second embodiment, a similar block-like wedge member cooperates with a U-shaped member mounted on the plunger.

Abstract: Venetian blind slats are stacked and clamped onto a support, and confined laterally, while leaving ends beyond the desired length to which they are to be cut, un-confined. Then in one stroke in a direction perpendicular to the support, the ends of the stack are sheared-off by a punching tool having a cutting edge which contacts longitudinal margins prior to the center of the slats.

Abstract: A sheet cutter comprises a fixed cutting member; a movable cutting member whose cutting edge slopes so that the movable cutting member has a V-shaped extension and/or notch; and a control member for controlling the stroke of the movable cutting member, whereby the movable cutting member is moved to overlap with the fixed cutting member to shear a sheet at a predetermined portion thereof.

Abstract: The invention provides an apparatus for cutting or paring a slice of material from a block (17) of material which has a lamina or strata structure, comprising a reciprocable blade (11) having a cutting edge (20, 21) arranged to enter and traverse the block of material to remove a slice therefrom during a forward or cutting stroke of the blade, in which means is provided to move the cutting edge of the blade in a direction having a component transverse to the direction of reciprocation of the blade after the blade has penetrated a short distance into the block thus to pare the slice from the remainder of the block substantially following the path of a boundary between lamina or strata in the block. In a preferred form the blade is wider than the slice to be cut and is formed with inclined portions 11c, 11d) at its leading or cutting edge, which portions are arranged so that the cutting edge of the blade is in the form of wide angled "V".

Abstract: This invention is directed to means (40) for severing multiple, electrical connector housings (10) into single units. The apparatus hereof features a cutting or web severing station (40) comprising one or more horizontally reciprocating cutting bars (30), each said bar (30) at one end thereof having means (32) for mounting same on a pivoting lever arm (46, 52), and at the opposite end (34) a 1) hold-down flange (36) which acts to restrain any vertical movement of said webs, and 2) recessed web severance portion (38). Cooperating with said bar(s) is an essentially "L" shaped lever arm (46) mounted for pivotal action at the junction of the arms thereof, where one arm (48) is mounted for vertical movement by means of a hydraulic piston (50). By virtue of said vertical movement, the remaining lever arm (52), to which such cutting bar (30) is mounted, is caused to reciprocate within a given plane between a web severance position "B" and a remote position "A.

Abstract: In a reciprocating blade for cutting sheet material, a lower cutting part includes a forward cutting edge defining portion and a rear body portion. The body portion has two parallel side faces. The cutting portion has first, second, third and fourth side surfaces. The first side surface is located in a reference plane parallel to and mid-way between the side faces of the body portion. The fourth side surface is in the same plane as one of the side faces of the body portion. The second side surface is inclined to the reference plane, extends between one side face of the body portion and the first side surface, and intersects the first side surface to define the cutting edge. The third side surface is inclined to the reference plane and extends from the rear of the first side surface to the other side face of the body portion. At least the first side surface is covered with a layer of hard material. During use of the blade the second side surface is periodically sharpened.

Abstract: Silage cutter has a U-shaped frame which is movable vertically on a mounting rack. The frame has a pair of lateral members and a front member connected thereto by a pair of corner coupling elements. Each member has a front and a rear cutting blade slidably mounted thereon and driven in opposite directions by an arrangement of a drive cylinder and a lever on each lateral member. The blades on the lateral members drive the blades or the front member through force transmitting means such as upper and lower sets of steel rollers in each corner coupling element.

Abstract: A self-cleaning cutter knife (100) is described for use as a replacement for prior art cutter knives in product inspection and cutting apparatus having a cutting wheel assembly including a knife guide having angularly spaced radially oriented knife support slots through which cutter knives having tangs extending therefrom move between a retracted noncutting position and an extended cutting position. The self-cleaning cutter knife (100) includes a shank (102) and a tang (114) similar to those of prior art cutter knife (10) but also includes a secondary blade (126) whose cutting edge (128) is positioned to cut product remnants adhering to the shank (102) as it retracts into the cutting wheel assembly. The secondary blade (126) diminishes the knife jamming that results from accumulation of large product remnants in the cutting wheel assembly knife slots.

Abstract: An apparatus for cutting a used ink ribbon wound in a pancake form, comprising a ribbon holder for setting a position of the ink ribbon, and a plurality of cutting blades extending radially on one surface of a base member movable relative to the ink ribbon. When the base member is driven to the ink ribbon, the cutting blades cut the ink ribbon through a plurality of cutting planes extending radially from the axis of the ink ribbon in a pancake form.

Abstract: A lamina clipping device and method are presented whereby edge excess lamina portions of a laminated substrate can be trimmed at the corners in an efficient and clean, finished fashion. One blade is stationarily mounted to a base and a second movable blade is joined thereto whereby a substrate can be positioned against the stationary blade and the movable blade actuated to clip the excess lamina along the edge thereof as the blades come together.

Abstract: In a reciprocating blade for cutting sheet material, a lower cutting part includes a forward cutting edge defining portion and a rear body portion. The body portion has two parallel side faces. The cutting portion has first, second, third and fourth side surfaces. The first side surface is located in a reference plane parallel to and mid-way between the side faces of the body portion. The fourth side surface is in the same plane as one of the side faces of the body portion. The second side surface is inclined to the reference plane, extends between one side face of the body portion and the first side surface, and intersects the first side surface to define the cutting edge. The third side surface is inclined to the reference plane and extends from the rear of the first side surface to the other side face of the body portion. At least the first side surface is covered with a layer of hard material. During use of the blade the second side surface is periodically sharpened.

Abstract: In a reciprocating blade for cutting sheet material first and second side surfaces inclined relative to one another intersect to define an elongated cutting edge. The cutting edge is offset from a reference plane located midway between the side faces of the blade so that the first side surface passes through the reference plane in going from its associated side face to the cutting edge. At least the first side surface is covered with a thin coat of hard material harder than the base material of the blade. During use the second side surface is ground to cause the cutting edge to be defined by the hard material covering the first side surface. As a result of repeated sharpening grindings of the second side surface the cutting edge gradually moves to and then beyond the reference plane to give the blade a long useful service life.

Abstract: A steel rule die is disclosed having strengthening layers bonded to the die board to stiffen the die board against flexing during handling, while alleviating the tendency to loosen the steel rule during handling and enhancing the durability of the die. KEVLAR graphite fiber fabric is impregnated and bonded to either face of the die board with epoxy resin.

Abstract: A masking paper is wound in a roll form and includes a relatively thin synthetic resin film folded in a plurality of parallel pleats and a relatively thick tape disposed along a longitudinal margin of the film and having a pressure sensitive adhesive layer formed on the opposite sides thereof. An apparatus for applying and dispensing the masking paper includes a housing accommodating the masking paper in a roll form, a group of rolls for taking the masking paper out of the housing and a cutter blade for cutting the masking paper. The cutter blade is reciprocated back and forth across the masking paper, and is retracted from the masking paper during its movement from a starting position.

Abstract: An apparatus for removing a pellicle that is adhesively bonded to a photomask. A first embodiment of the invention is provided for removing a pellicle having a generally rectangular shape. The photomask is placed in a housing with the pellicle facing down. A pair of blades are mounted on a carriage that are longitudinally movable within the housing. The blades are adjustable such that the cutting edges are immediately below the surface of the photomask. The carriage is driven by a rack and pinion assembly causing the blades to cut through the adhesive layer bonding the pellicle to the photomask. A second embodiment of the invention is provided for removing a pellicle having a generally circular shape. In this embodiment, the blades are mounted on a rotating bar. Rotation of the bar causes the blades to cut through the adhesive layer bonding the pellicle to the photomask.

Abstract: Strip retainer and stripper which is used on a stamping and forming machine for stripping or removing the stock material from the pilot pins and punches when the punches and pilot pins move from their closed positions to their open positions, comprises one or more wires in the operating zone of the machine. Each wire extends transversely across, and intersects, the path of reciprocation of the punch assmebly. The wire does not intersect the path of reciprocation of the pilot pins or the punches and is located between the punches and pilot pins and the surface of the stock material. The ends of the wires extend beyond the path or reciprocation of the punch assembly and are secured by fixed securing devices.

Abstract: A self-sharpening perforating punch head for perforating a web of plastic film is formed of one or more plates of a semirigid plastic resin, e.g. acetal homopolymer. The head has a row of tapered and beveled teeth which form a cutting edge at the back plane of the head. The cutting edge renews itself as the material wears by plastic-on-plastic abrasion. There are gaps provided at intervals among the teeth.

Abstract: A cutting head for cutting spread sheet material and using a vertically reciprocating knife achieves a light-weight, low cost, low maintenance and high stroking speed design through a unique combination and arrangement of parts wherein the knife drive motor is isolated from rotation with the knife about the theta axis without using a conventional swivel mechanism. The knife has a leaf spring portion directly connected to the eccentric member, fatigue failure of the leaf spring portion of the blade is inhibited by antivibration stops and by a varying cross-section, a simple sharpener mechanism sharpens the blade on either one or both side faces, and a roller guide restrains the lower portion of the blade to the vertical axis with minimum frictional loss.

Abstract: A cutting and scoring line consisting of a blade (1) of steel with a cut bevel (2) formed on one longitudinal side of the blade, and the blade (1) is hardened in the area of the bevel (2) and the bevel has a fine grind (5) in the hardened area (4) starting from the tip (3) of the bevel.

Abstract: The present invention relates to a saw blade holder for precision saws. Precision saws are designed to hold a saw blade between two parallel arms. Upper and lower blade holders mount the saw blade on the arms. The present invention relates to the lower blade holder and comprises two clamping elements which are designed to threadably engage and fit inside of a slotted tubular member. The blade passes through the slot in the tubular member and is clamped between the two clamping elements. The tubular member is comprised of a finely divided metal which has been shaped into the desired configuration utilizing a lubricant which is embedded throughout the thickness of the tubular sleeve. This lubricant is released over the lifetime of the tubular member so as to continually lubricate the wear points thus reducing wear and the adverse effects associated therewith.

Abstract: An apparatus for cutting and crimping pipe having a first jaw and a second jaw between which a pipe is placed to be crimped and/or cut. At least one of the first jaw and the second jaw is mounted for relative reciprocating movement toward and away from the other, whereby the jaws are capable of cutting and crimping pipe placed therebetween. A guide mechanism, preferably a guide plate, is disposed at an angle to the jaws for guiding a pipe placed between the jaws, whereby the pipe can be cut and crimped at an angle determined by the angle of the guide mechanism. It is preferable that the jaws have a first section provided with a mechanism for cutting and crimping pipe and a second section without a mechanism for cutting pipe whereby pipe placed in the second section may be crimped only. Preferably the first jaw is driven by a hydraulic ram.

Abstract: A punch pin cutting edge configuration having a leading edge and a following edge is described. The leading edge engages a workpiece, such as paper, before the following edge. The following edge is at a steeper angle than the leading edge relative to the workpiece being punched. The cutting edge thus produced reduces the force necessary to punch through the workpiece.

Abstract: A buttressed edge cutting tool wherein alternating buttresses and grooves are formed across blade faces with each groove having a depth fairing smoothly to zero at its end remote from the cutting edge.

Abstract: A cutting device is provided for use with a printer having a plurality of movable blades which are disposed in side-by-side relationship and driven in a direction perpendicular to the length of the blade. A plurality of solenoids are provided for driving each movable blade. A spring, which is arranged to be depressed by the movement of the movable blade, applies a pressure to the paper to fix the paper in position before the movable blade reaches the cutting position.

Abstract: A punching tool wherein the knife is a strip of steel and has a cutting edge flanked by two mutually inclined concave facets. The facets are disposed between the cutting edge and two lateral surfaces which have concave portions adjacent the respective facets. Those portions of the knife which are disposed between the facets and the concave portions of the respective lateral surfaces are rounded.

Abstract: The tool holder of a machine for cutting a supply of insulated electrical conductor into discrete lengths employs a standard cutting blade. The standard blade serves as the outer boundary of the tool holder and of the remainder of the machine, thereby assuring that the cut lengths can pass to the next processing station without striking any component and thereby become disoriented. Use of the standard cutting blades is accomplished by employing conventional fasteners to retain the blade on the tool holder. The cutting blade is located in the tool holder by a slotted member and blade shank end locator.

Abstract: A machine for cutting coarse sod into relatively small plugs for ready packaging and subsequent transplanting, comprising an endless conveyor belt upon which comparatively large rectangular sections of sod can be deposited, so that the sections of sod can be moved intermittently toward a sod cutting device. The sod cutting device preferably is of the single pass cutter type, utilizing a plurality of elongate, closely grouped blades designed to periodically move in unison downwardly into contact with sod to be cut, with such downward cutting movements being immediately followed by an upward movement, thus to permit an advance of the section of sod without interference. I coordinate the movements of the sod cutting device with the belt advance, such that forward movement of a section of sod is in each instance prevented until the cutting blades are clear of the section of sod being cut.

Abstract: A double duty paper punch for punching selected combinations of holes in up to fifty sheets of paper comprises a die-cast base with a steel die plate of angle cross section seated on the base with a downwardly projecting flange received in a recess in the base. An elongate punch holder, also a die casting, has a rear portion seated on a rear portion of the die plate and a forward portion spaced upwardly from the die plate to receive the paper to be punched. Rivets through aligned holes in the punch holder, die plate and base secure these parts together. The punch holder has a plurality of punch-receiving bores aligned with holes in the punch plate and base selectively to receive individual punches, each having a stem and a head with a spring acting between the head and the punch holder to hold the punch in raised portion.

Abstract: A machine for processing plywood sheets which pass one behind the other includes a horizontal transporting and supporting roller, a cutter located above the roller and movable toward and away from the roller, a transporting device including a machine table and at least one transporting band rotatable about the machine table, and a testing device for rejecting defective plywood sheets or sheet portions, which has a plurality of testing rollers supported on pivotable parallel levers and is located above the machine table, so as to abut against the plywood sheets which are transported by the transporting device.

Abstract: The press, which is suitable for creasing, scoring, perforating or cutting of board or similar material, comprises two upright spaced-apart frame members, which are interconnected by a transverse member and each of which is provided with a vertical guide, a horizontal press beam, which is mounted in the vertical guides and is connected with a crank, and a pressure beam, which is fixed on the frame members and is parallel to the press beam. The crank is fixed on one of the frame members and has an actuating arrangement. A work table is provided on the pressure beam. A bearing surface, which is vertical in the pressing position and changes at its upper end into a horizontal projecting pressure surface, is provided at the bottom end of the press beam at which are also fixed spaced-apart resilient holders.

Abstract: A knife blade for cutting sheet material has a cutting portion which includes two adjoining faces defining a cutting edge and comprises a relatively soft or high wear base material and a relatively hard or low wear coating. One of the faces is formed by the relatively hard coating and the other face is formed by the relatively soft base material. Both of the faces of the cutting portion are bevelled and are exposed to the sheet material during cutting. Another knife blade embodying the invention has a cutting portion which includes one face formed of a relatively soft base material and another corrugated face formed of a relatively hard coating.

Abstract: In a channel press for producing bales, preferably tied, of non-metallic waste materials, such as office waste and the like, a press piston is reciprocably mounted in a press channel or shaft into which the waste material is introduced. A knife member is mounted on and is movable with the press piston. A stationary counterknife member is located in the press channel. At least the stationary knife has individual teeth each formed with a point. The teeth are located along a line directed oppositely relative to the line of the cutting edge of the movable knife member.

Abstract: A device for continuously cutting and winding a web includes a cutter blade mounted so that a flat portion thereof is maintained in elastic contact with an outer surface of a web winding roll so as to prevent the web from creasing and folding as it is being cut.

Abstract: An improved film cutter for severing sheets of soft stretch film which is drawn in a plane into a wrapping machine from a continuous source of such film comprises a first elongated knife blade extending laterally across the plane defined by the film and having a serrated cutting edge facing the film. A knife bracket extends laterally across the opposite side of the film plane and forms a channel such that the first knife blade may be moved or inserted into the channel to sever the film. The knife bracket comprises an elongated first member, with a knife mounting bar secured thereto and spaced therefrom to define the channel. The knife mounting bar includes a flange extending away from the channel and toward the film oriented at an acute angle to the knife mounting bar such that the extended edge of the flange forms a thin film contacting edge of the channel.

Abstract: The cutter mechanism for slitting laminate material interconnecting overlapping borders of adjacent articles includes an elongated body that has a pair of upwardly-extending guide feet on opposite ends along one edge of the body and downwardly-extending guide feet on opposite ends adjacent the other edge with a generally rectangular slot between the respective feet and extending from opposite ends. The slots have bases which extend perpendicular to the opposite edges and thus perpendicular to the path of movement of the cutter means to provide sharp cutting edges between the respective feet.