Scrap stripper and chopper with conveyor

There is disclosed a board cutting machine in which a plurality of grooves are cut in a board such as a board of insulating duct material to permit the board to be folded into a multi-sided shape. As strips are cut from the board an extractor unit extracts the scrap strips and directs them to a chopping unit where the scrap is chopped into small pieces.

This invention relates to board cutting machines, and more particularly to 
machines for cutting grooves in a piece of duct board so that it may be 
folded into a multi-sided form to provide a duct. 
Board cutting machines for forming shiplap grooves in duct board are 
well-known. They are examplified in the patent to Barr, U.S. Pat. No. 
3,605,534 which is incorporated herein by reference. The cut strips leave 
the machine of Barr with the board and are manually extracted therefrom 
before 21a board is formed into a duct. It would be advantageous to have a 
machine for automatically removing the cut strips and reducing them to a 
form which can be readily handled. 
It is an object of this invention to provide a board cutting machine in 
which the cut strips can be automatically removed and reduced to small 
pieces to facilitate handling or easily removed by hand after grooving. 
Another object of this invention is to provide a board cutting machine in 
which the cutters may be adjustably positioned across the machine for 
automatically conveying the cut strips from any position across the 
machine to a chopping section where they are chopped into small pieces and 
delivered to a central location for further handling. 
Another object is to provide a board cutting machine as in the previous 
object in which the cut strips of material are removed from the board 
immediately after it is cut and while the board is still passing through 
the machine. 
Another object is to eliminate the undercutting characteristic of the 
machine of the Barr patent. 
Another object is to reduce the force necessary to move a sheet of material 
through the machine of the Barr patent. 
Other objects, features and advantages of this invention will be apparent 
from the drawings, the specification and the claims.

The Barr patent identified above shows the general layout of the machine of 
this invention and illustrates how the several cutters are selectively 
positioned across the machine so that several shiplap grooves may be cut 
in the board to facilitate forming a duct from the board. Reference to 
this patent is made for a disclosure of the details of the machine and its 
operation, this invention being an improvement upon the machine 
illustrated in the Barr patent. 
Referring first to FIG. 1, a sheet of duct board 10 is shown moving through 
the machine. The means for moving a board to be cut through the machine is 
provided by a pair of front pinch rollers 11 and 12 and a pair of rear 
pinch rollers 13 and 14. Also, rollers 15 and 16 are provided which 
support the board while it is being cut. 
A cutting means is indicated generally at 17. The cutting means includes a 
plurality of blade supports and blades such as shown in FIG. 1. The 
cutting means includes a support bar 18 which extends across the machine 
and a plurality of blade supports 19 which are releasably locked to the 
bar 18 at the selected positions therealong. 
Blade means indicated generally at 21 is provided on each blade support. As 
will be explained hereinafter, the cutting edge of the blade means when 
unstressed extends downwardly and inwardly toward the strip being cut at a 
slight angle to the vertical, causing the cut strip sides to be angled, 
facilitating removal of cut strip. If the blade cutting edge which extends 
in a vertical direction is vertical when unstressed, it has been found 
that the blade will make an undercut which tends to make the cut strip 
difficult to extract from the board. 
An extractor means indicated generally at 22 is carried by each blade 
support and lifts the cut strip from the board as it is being cut. As 
shown in FIG. 1, the extractor means includes a short lifter section 23 
which may be integral with the rear of blade 21a and extends in an upward 
direction. Preferably, the lifter section 23 is fabricated with the 
general cross-sectional configuration of the blade 21a to which it is 
attached. With some configuration of blades the extractor need not be 
attached to the blade. Where the material being cut tends to hang up on 
the extractor it is secured to the blade as shown in FIGS. 1 and 2. This 
short section 23 forces the cut strip of board in an upwardly direction 
into the chute section 24 of the extractor means. The chute section 24 is 
preferably carried on arm 25 which is in turn carried directly by the 
blade support. 
The extracted strips of board are conveyed to a chopping means indicated 
generally at 26 which includes extractor rollers 27 and 28 and cooperating 
blade roller 29 and base roller 31 which chop the extracted strip into 
short sections. The sections fall onto the conveyor indicated generally at 
32 which conveys all of the scrap to a central location for easy handling. 
The blade indicated generally at 21 is made up of two parts which are shown 
in FIGS. 2 and 3. The blade 21a as shown in FIG. 2 includes two almost 
vertical sections 21c and 21d. It will be noted that blade section 21c is 
bent so that its cutting portion is preferably approximately 5.degree. 
from the vertical. Blade section 21d is bent so its cutting section is 
preferably approximately 15.degree. from the vertical. These blade 
sections depart from the vertical in a downwardly direction toward the 
strip being cut as it has been found that the cutting action will result 
in the material being cut bending back to substantially a vertical 
position. The angular relationship of these vertical blade sections with 
the vertical which for purposes of this description is assumed to be 
normal to the face of the board 10, are not critical, but should be such 
that no undercut is made which would make it difficult to extract the cut 
strip from the board. The vertical section 21d is joined to horizontal 
section 21e and to horizontal section 21f, forming an integral blade. It 
has been found that section 21d should have a greater angle than 21c, to 
prevent an undercut, causing difficulty in removal of the cut strip. The 
reason for this is not known. At any given point on the board the material 
being cut by a blade such as is shown in FIG. 4 has already been cut free 
from the board by blade section 21a and blade 21b before blade section 21d 
begins its cut. It is believed that this results in the strip being cut 
tending to turn under forces imposed by the blade. 
It has been found that less force is required to cut a strip from a board 
if all undercutting is avoided. In force tests between blades of the form 
of FIG. 4 which were similar in shape except for the angled sections as 
taught herein to avoid undercutting it was found that angling the blades 
as taught herein reduced the force required to cut out a strip by 27 
percent. 
The extractor member 23 is also shown in FIGS. 2 and 4 and it will be noted 
that the extractor member is step-like in configuration and attached 
directly to the rear of blade section 21a. As noted above, it need not be 
attached in all forms of blades. The joint between the blade 21a and the 
chute section 23 should be such that the scrap strip will move smoothly 
into the chute. Thus, cut material passing over the blade 21a will be 
directed in an upwardly direction to the chute 24 (FIG. 1). 
FIG. 3 shows the blade 21b to also be bent at about a 5.degree. angle so 
that it will not undercut during use. 
FIG. 4 shows schematically the relationship of the two blades 21a and 21b, 
in the installed condition. From FIG. 1 it will be apparent that the blade 
section 21b has its lower horizontal run in front of the comparable lower 
horizontal run of the blade 21a. The configuration of the deflector 23 is 
not critical and might be any shape which will deflect the cut-out section 
of board upwardly. Preferably, the cross-section is similar to the blade 
configuration so the cut strip will be removed smoothly. 
The chopper section is best shown in FIG. 5 and 6. The strips of board pass 
from the extractor through the two pinch rollers 27 and 28. These pinch 
rollers are rotated at the same speed as the rollers 13 and 14 in the main 
bed of the machine and isolate the chopping rollers from the grooving 
machine. It will be noted from FIG. 6 that these rollers as well as the 
rollers 29 and 31 extend the entire width of the machine and will receive 
scrap strips from any desired setting of the several cutter means. 
The strips are broken into short sections by the cooperating blade roller 
29 and base roller 31. The blade roller 29 has attached thereto a radially 
extending blade 33 for chopping the strip board as it passes through the 
machine. The base roller 31 has mounted thereon a member 34 having an 
integral slot 35 therein for receiving the blade 33. Member 34 is 
constructed of polyurethane, or a similar material. The rollers 29 and 31 
are driven at a slightly greater speed than the rollers 27 and 28 to 
assist in the chopping action. The rollers 29 and 31 are of course, driven 
synchronously so that the blade and groove will mate each time they oppose 
each other. The gears indicated generally at 36 for driving the rollers 29 
and 31 are conventional in form and are driven by power means not shown. 
Rollers 27, 28 29 and 31 are driven by a separate conventional motor and 
chain drive, not shown. 
The conveyor indicated generally at 32 conveys the chopped scrap to one 
side of the machine. The conveyor belt assembly is conventional in form. 
Any desired form of conveyor system may be used or the conveyor system may 
be dispensed with and a chute utilized to collect the scrap if it is 
desired to assemble the scrap in a more central location than the general 
area below the chopping means. 
From the above it will be seen that the objects of this invention have been 
attained. The cut strips from a board are automatically removed from the 
board as they are being cut and are chopped into small pieces which may be 
gathered in a central location for further handling. The need for manually 
removing each of the cut strips from the board after it is cut has been 
eliminated. 
It will be apparent from the disclosure that the scrap chopper-extractor 
system may be used with any form of cutter blade such as V-blade and the 
invention is not limited to the form of blade shown. 
The foregoing disclosure and description of the invention is illustrative 
and explanatory thereof and various changes in the size, shape and 
materials, as well as in the details of the illustrated construction may 
be made within the scope of the appended claims without departing from the 
spirit of the invention.