Apparatus for cutting flexible materials

A method and apparatus for cutting a length of flexible material from a web includes, more particularly, a method and apparatus for cutting a predetermined width of carpeting without removing pile fibers from the backing, in a manner which greatly enhances efficiency and productivity.

BACKGROUND OF THE INVENTION 
1. Technical Field 
The present invention relates, generally, to methods and apparatus for 
cutting a length of flexible material from a web, and, more particularly, 
to methods and means for cutting a predetermined width of carpeting, 
without removing pile fibers from the backing, in a manner which greatly 
enhances efficiency and productivity. 
2. Description of the Background Art and Technical Problems 
Floor coverings in restaurants, homes, factories, hotels, and offices 
continue to involve widespread use of flexible webs of material, including 
vinyl, foamed products, as well as natural and synthetic carpeting. 
Although colorful patterns have always been popular, modern applications 
increasuingly employ the use of adjacent strips of differently colored 
carpeting, or feature stripes, particularly in corridors and around the 
perimeter of large rooms. Additionally, carpeting is replacing wood as a 
baseboard and wall covering material. 
The appearance of a carpeted surface is largely determined by the manner 
and quality of installation. However, presently known installation 
techniques, which have not changed significantly in the past one hundred 
years, are cumbersome, tedious, strenuous, and time consuming. 
Carpeting is typically cut from large rolls into strips at the job site. 
Small hand-held tools having a generally rectangular, flat, double-edge 
blade integral therewith, are used almost exclusively to cut carpeting. 
One corner of the blade protrudes from the tool and is used as the cutter, 
so that each blade can be inverted as needed to yield four cutting zones 
per blade. After the surface to be carpeted is measured, the web from 
which the strip is to be removed is inverted and the appropriate width is 
marked off on the backside, or underside, thereof. Using a straightedge, 
the cutting tool is pulled through a length of carpeting, cutting through 
one or more layers of woven backing (nap), foam, adhesive, or plastic, for 
example. Inasmuch as carpeting is cut from the backside with the normally 
exposed pile compressed therebeneath, many individual strands or clusters 
of fibers are inevitably severed. 
When two pieces of cut carpeting are put into place with the cut edges 
adjacent, it is desirable to conceal the seam therebetween. However, to 
the extent carpet fibers are removed from both mating edges during 
cutting, an unsightly seam is created because differences in marginal 
edges are exaggerated. 
Carpet laying is highly labor intensive; contractors are customarily paid 
by the yard, not by the hour. Thus, it is important to minimize the time 
required to install a given amount of carpeting. Presently, the cutting 
procedure generally entails measuring the area to be carpeted; turning the 
carpet "backside up"; marking the carpet; lining up the straightedge; and 
pulling the cutter tool along the straightedge. Typically, the cutting 
zone of a blade remains sharp for perhaps eight to twelve feet of cutting, 
depending on the composition and structure of the carpeting. Moreover, 
since the cutting is commonly done on wood, concrete, or tile floors, the 
blade is easily bent, sheared, or nicked. As a result, considerable time 
is spent inverting, discarding, and changing blades. 
SUMMARY OF THE INVENTION 
The present invention provides methods and apparatus for cutting a strip of 
flexible material of a predetermined width from a web thereof, in a manner 
which greatly enhances quality and efficiency. A preferred embodiment of 
the present invention provides an apparatus for cutting the primary and 
secondary backing of carpeting without severing the pile, or at least 
significantly reducing such tendencies. This is accomplished in one aspect 
of the invention by providing a flat, generally rectangular carrier or 
bracket having a lower surface adapted to slide along the floor and an 
upper supporting surface, or deck, over which a web of carpeting is 
directed during cutting. A blade holder, rigidly connected to the aft 
portion of the deck, presents the vertical leading edge of a thin, flat, 
rectangular blade substantially orthogonal to the plane of the web. 
Sufficient clearance is provided in the blade holder slot to allow the 
blade to reciprocate up and down, at high frequency and low amplitude, 
during the cutting process. This relative movement between the blade and 
the carpet is substantially confined to the plane of the blade and results 
in a sawing action. Consequently, carpeting having a thick backing can be 
cut with relative ease, thus promoting higher productivity. In addtion, 
the fact that the pile in the vicinity of the freshly cut edge is left 
intact allows for nearly perfect seams between adjacent segments.

DETAILED DESCRIPTION OF PREFERRED EXEMPLARY EMBODIMENTS 
Referring to FIGS. 1, 3 and 6, a cutting machine 100 generally comprises a 
carrier 10, including a base 12 and a deck 13 over which a web of 
carpeting or other flexible material is directed for cutting. 
In a preferred embodiment, carrier 10 is generally rectangular as viewed in 
plan and may be inclined upwardly from the front edge 14 thereof to 
provide an entry ramp for web 11. If desired, the deck 13 may incline 
upwardly over the full distance from a front transverse, or fore edge 14, 
to a rear transverse or aft edge 15. To one side, deck 13 is provided with 
a generally upright, longitudinally (i.e., fore-and-aft) extending guide 
surface 16 for engagement by an edge of web 11 while passing through 
machine 100 during a cutting operation. Disposed outwardly from and 
generally paralleling the plane of guide surface 16, carrier 10 is also 
provided with a longitudinal or fore-and-aft extending handhold member 17. 
Rearwardly of carrier 10 and secured to the aft section thereof is provided 
a transversely extending track 26, which, according to a preferred 
embodiment of the invention, includes an upwardly opening channel member 
27 that extends the full transverse dimension of carrier 10. A handle 
assembly 28 is engageable with track 26 and carries a cutting blade 29 for 
cutting material 11 moving relative thereto, as more fully described 
hereinafter. 
Handle unit 28 comprises a plate member 30 and a rearwardly extending 
handle 31. Generally normal to handle 31, plate member 30 includes a 
transversely extending depending member 32 which slidably engages channel 
member 27. With depending member 32 properly engaged within channel 27, 
the upper surface of plate member 30 is generally parallel to base member 
12. 
Plate member 30 and depending member 32 are provided with a fore-and-aft 
extending slot or recess 33 for retaining cutting blade 29 (see FIG. 5). 
Blade 29 is suitably disposed in slot 33 with a leading edge 62 facing 
forward edge 14 of bracket 10. Slot 33 is generally upright with an upper 
opening terminating at plate 30 and a lower opening terminating at channel 
27. Thus, when disposed in slot 33, blade 29 rests on the generally flat, 
transverse bottom portion of channel member 27 and projects upwardly 
substantially above plate member 30, as shown in FIG. 3. For reasons more 
fully described hereinafter, the transverse dimension of slot 33 
preferably exceeds the thickness of blade 29 by about 0.001 to 0.125 
inches, and more preferably by about 0.002 to 0.005 inches. The 
fore-and-aft dimension of slot 33 preferably exceeds the width of blade 29 
by about 0.001 to 0.050 inches, and more preferably by about 0.015 to 
0.020 inches. 
Conventional cutting blades presently used in the hand-held cutting tools 
discussed supra may be advantageously employed in a preferred embodiment 
of the present invention. Exemplary blades, generally corresponding to 
blade 29, are desirably approximately 2.25 inches high (the leading edge); 
0.750 inches wide (the fore-and-aft direction of slot 33); and 0.015 
inches thick. Thus, slot 33 may advantageously have a fore-and-aft 
dimension in the range of about 0.750 to 0.800 inches (preferably 0.750 to 
0.765 inches), and a transverse dimension in the range of about 0.015 to 
0.065 inches (preferably 0.017 to 0.020 inches). 
Blade 29 is a double-edged blade so that it may be rotated 180 degrees to 
present a fresh edge once an active cutting edge is worn. Since less than 
half of blade 29 projects above plate member 30 for cutting, the blade can 
also be inverted to present a fresh cutting edge. 
The edges of blade 29 are extremely sharp so that protection against 
possible unwitting cutting accidents are considered appropriate. To reduce 
the tendency for such accidents, a pivotal cover member 37 can extend down 
over the upper extremity of blade 29. As shown in FIG. 3, the cover member 
37 also remains well above the material 11 being cut and out of contact 
with the blade so that it does not interfere with the cutting operation. 
Cover member 37 is mounted on carriage 38 which in turn is slidably 
disposed on a rear hold-down slat 22 (discussed below). To provide access 
to blade 29 when desired, cover member 37 is pivoted on a transverse hinge 
39 to the position shown in phantom lines in FIG. 3. Alternatively, the 
blade guard may extend along the entire length of slat 22, and comprise a 
semicircular member made from a synthetic polymer, for example, 
"plexiglass." 
Referring now to FIGS. 1, 2, and 3, a generally rectangular hold-down 
member 18 is pivotally connected to carrier 10, for example by respective 
hinges 19, to aid in the control of the material moving through the 
apparatus. In the normally down position, hold-down member 18 extends 
across the surface of deck 13 between hinges 19 and the oppositely 
disposed fore-and-aft edge of carrier 10. Hold-down member 18 may be 
raised or pivoted upwardly to an open position relative to deck 13, as 
indicated by the arrows 20 in FIG. 1, to facilitate placement of web 11 on 
deck 13 prior to cutting. 
Hold-down member 18 preferably comprises a lattice structure and includes a 
pair of generally parallel, transversely extending slat members 21 and 22 
having distal ends remote from hinges 19 and connected by a cross-member 
23. The forwardly disposed slat member 21 is spaced somewhat rearwardly 
from front edge 14 of deck 13 as generally shown in FIG. 1. A preferably 
transparent, plastic cross-member 25 is carried by slat member 21 and 
extends beneath rear slat member 22 adjacent guide surface 16. The lower 
surface of cross-member 25 is disposed generally normal to the guide 
surface 16 and serves to prevent the material 11 from creasing and/or 
curling relative to the guide surface. In view of its lattice 
construction, the hold-down member 18 exerts relatively little bearing 
pressure on web 11 passing therebeneath. Cross-member 25 makes it possible 
to watch and/or monitor the material 11 being conducted through the 
machine 100 for cutting, particularly as to its relation to the guide 
surface 16. A linear scale 24 may be advantageously disposed along the 
rear edge of the slat member 22 to provide a distance measure in the 
transverse direction across the deck 13 relative to the guide surface 16. 
The rear edge of rearwardly disposed slat member 22 generally coincides, 
vertically, with the rear edge 15 of deck 13. In this way, an imaginary 
line defined by leading edge 62 of blade 29 (i.e., L-L as best viewed in 
FIG. 8) may be held substantially perpendicular to an imaginary plane 
defined by web 11 (P as viewed in FIG. 2) proximate the cutting site 
during the cutting operation. This minimizes the resistance to cutting 
exhibited by web 11 to the extent that the portion of leading edge 62 
which engages web 11 is limited to the thickness of web 11. Furthermore, 
an orthogonal orientation of edge 62 with respect to the plane of web 11 
reduces the likelihood that web 11 may become pinched between edge 62 and 
plate 30 during cutting, as may otherwise occur if edge 62 were disposed 
at an acute angle with respect to the uncut portion of web 11. 
Alternatively, blade 29 may be disposed at an obtuse angle with respect to 
the uncut portion of web 11, as shown in phantom lines in FIG. 3. 
Plate member 30 is suitably provided with a depending rib 34 which is 
spaced rearwardly from member 32 by a distance corresponding to at least 
the thickness of a flange 60 forming an aft boundary of channel member 27. 
A pair of tap screws 35, having respective heads 36 adapted for finger 
manipulation, are spaced on opposite sides of handle 31 and threadedly 
engaged in rib 34. Screws 35 may be manually turned to engage the adjacent 
flange of channel 27 to secure handle unit 28 relative to deck 13. 
When the cutting machine is not in use, handle unit 28 is generally 
separated from the base member 12 for more convenient storage and 
transportation. When the machine is to be placed in service, handle unit 
28 is reassembled to carrier 10. To reassemble handle unit 28 to carrier 
10, depending member 32 of handle unit 28 is initially engaged in channel 
27. Thereafter, handle unit 28 is slidably manipulated to align blade slot 
33 to the desired linear dimension on scale 24 to provide for the needed 
width of material 11 as measured from the guide surface 16. After blade 
slot 33 is properly aligned relative to scale 24, handle unit 28 is locked 
in position by tightening the screws 35 against the flange of the channel 
27. 
Alternatively, handle unit 28 may be permanently mounted to deck 13 and 
guide 16 may be extendable from deck 13, for example by rollers or 
bearings (not shown). In that event, a scale, similar to scale 24, may be 
disposed on a sliding member interposed between guide 16 and bracket 10 to 
establish a desired predetermined distance between guide 16 and blade 29. 
A mechanism similar in function to screws 35 having heads 36 may be 
incorporated into guide 16 to maintain the position thereof at the desired 
distance from blade 29. 
With machine 100 set to cut the proper width, one end of material 11 is 
manipulated onto deck 13 beneath hold-down member 18 with the side edge of 
the material abutting guide surface 16. Cutting blade 29 is inserted into 
slot 33 and cover member carriage 38 slidably manipulated into position on 
rear hold-down slat 22 so that cover member 37 can be pivoted into 
protective position over the blade. 
With material 11 properly loaded into cutter 100 and cutting blade 29 in 
place, the machine is set for cutting. Cutting is advantageously effected 
by an operator working on the floor, by moving the cutting machine 100 
relative to web 11 as indicated in FIG. 2 by the arrows A and B. Movement 
of the machine is generally effected by pushing the same with one hand on 
handle 31 and the other on base member hand-hold 17. As web 11 is cut to 
form a pair of strips, handle 31 moves therebetween. Ordinarily, the 
cutting machine will cut material as fast as the operator is able to move 
the machine. To enhance the speed of operation of the machine, the bottom 
of base member 12 may be provided with fore-and-aft extending runners 40 
as shown in FIGS. 4 and 6, preferably coated with a low friction 
composition such as PTFE. 
If desired, cutting a web of material may alternatively be effected by 
pulling the material through the machine. While the operator holds and 
monitors machine 100 in a generally fixed position, a helpmate pulls the 
two severed strips of material 11 relative to the machine. 
When web 11 is carpeting or a similarly flexible material, it has been 
observed that blade 29 reciprocates up and down relative to the web during 
cutting. This motion is induced in the blade by (relative) movement of the 
web through the apparatus. Although the precise mechanism by which this 
occurs is not fully appreciated, it is desirable to maintain the 
dimensions of slot 33, as discussed above, to afford blade 29 the 
necessary freedom to vibrate. Blade 29 rests on channel 27 while retained 
in slot 33, but is not otherwise secured to cutting apparatus 100. 
It is generally desirable for handle unit 28 to remain rigidly attached to 
the aft portion of bracket 10, so that no relative movement may occur 
therebetween. This ensures proper alignment of blade 29 with respect to 
the web during use. 
Inspection of blade 29 after cutting reveals that an area of its leading 
edge, which are is longer than the thickness of the web, is marred during 
cutting. This suggests that the blade, the web, or both "jump" up and down 
during cutting. When blade 29 is constrained, for example by manual 
application of pressure with a finger, the resistance to cutting is 
increased. This is presumably because the relative movement between the 
blade and the web is impeded. Thus, although it is desirable for blade 29 
to vibrate up and down in recess 33, satisfactory results may be obtained 
as long as limited relative motion between the blade and the web is 
permitted. This sawing action, somewhat akin to the motion of a saber saw 
blade, apparently results from the interaction between the sharp blade and 
the relatively unconstrained width of the flexible web. 
An important advantage of the present invention is that relatively few nap 
fibers are cut by blade 29 in machine 100; the blade appearing to select a 
path of least resistance through the material to the extent provided or 
permitted by the clearance allowed in slot 33. In view of the relatively 
few pile fibers that are cut and the accuracy with which machine 100 cuts, 
when the machine-cut edges of two pieces of carpeting are brought 
together, a seam is often not detectable or, at most, only faintly 
observable after the fibers at the joint are brushed slightly. 
A carpeting installer working with the cutting machine described herein can 
cut carpeting many times faster than with the common hand-held tool used 
in combination with a straight edge. Since cutting blade 29 is not 
subjected to dulling contact with wood, concrete, or other hard surfaces, 
each blade is capable of cutting up to hundreds of feet before a 
replacement is necessary. When cutting blade 29 requires reversing, 
inverting or replacing in cutting machine 100, the worn blade is simply 
removed and a fresh blade dropped into slot 33, as opposed to the time 
consuming disassembly and reassembly associated with the small hand-held 
tool. Thus, operation of cutting machine 100 involves minimal unproductive 
lost time. 
Turning now to the embodiment of FIGS. 7-9, like reference numerals on a 
cutting machine 41 indicate general correspondence with the similar 
elements described in connection with cutting machine 100. A carrier 42 
for cutting machine 41 terminates rearwardly with a track 43 that takes 
the form of a transversely extending rib 44 for engagement by a detachable 
handle unit 45. Rib 44 is spaced from deck 13 and generally extends the 
full transverse dimension of base member 42. 
A handle unit 45 comprises a plate member 46 that rearwardly mounts handle 
31. Forwardly, plate member 46 is provided with a depending, downwardly 
opening transversely extending channel member 47. Channel member 47 is 
engageable upon, and receives therein, the rib 44. With channel member 47 
properly engaged upon rib 44, the upper surface of plate member 46 
generally corresponds to the height of deck 13 of carrier 42. Generally in 
the vertical plane of the axis of handle 31 and rearwardly of channel 
member 47, plate member 46 is provided with a fore-and-aft extending slot 
48 for receiving the cutting blade 29. As shown in FIG. 8, slot 48 is 
closed at the bottom so that cutting blade 29 is fully contained by handle 
unit 45. 
Handle unit 45 is engaged upon and adjusted relative to linear scale 24 and 
thereafter secured in the desired position in a manner generally similar 
to that described in conjunction with handle unit 28. For its securement, 
handle unit 45 is provided with respective lateral projections 49 that 
extend from a rear flange of channel member 47. Screws 35 are threadedly 
engaged in projections 49 and are manually adjusted to engage with rib 44 
to secure handle unit 45 onto carrier 42. 
Cutting machine 41 operates generally similarly to machine 100 and offers 
all of the advantages described with reference to it. 
Those skilled in the art will appreciate that the degree of flexibility 
exhibited by a web of material suitable for use in the cutting machine 
described herein may vary greatly. Thus, although a preferred embodiment 
is described with reference to a web of carpeting, the foregoing 
advantages may also be obtained in conjunction with, for example, 
wallpaper, roofing, shingles, ceiling tiles, fabric, leather, foam, 
quilts, tar paper, cardboard, fiberboard, plastic, foamboard, paper, matt 
board, and vinyl base. 
It will be understood that the foregoing description is of preferred, 
exemplary embodiments of the present invention and that the invention is 
not limited to the specific forms shown. For example, guide 16 may be 
modified or omitted when it is desired to cut other than in a straight 
line. If, for example, a particular pattern is to be cut, the operator may 
guide the machine along a pattern line, keeping the blade aligned 
therewith. Furthermore, triangular, curved, or any other sharp-edged blade 
configuration may be employed, to the extent that at least a limited 
degree of relative motion between the blade and the web is permitted. 
These and other modifications may be made in the design and arrangement of 
the components without departing from the spirit of the invention as 
expressed in the appended claims.