Method and apparatus for applying a tab to the edges of a mailer to hold the same together

An apparatus for automatically applying a pressure-sensitive tab to the edge of a mailer which includes a feed spool of pressure-sensitive tape. The pressure-sensitive tape is fed through a tape slot of a tape guide block from where it is wound upon a driven windup spool. A pneumatically driven (or, if desired, solenoid driven) punch and die arrangement is positioned so that upon actuation, the die cuts a circular segment of the tape and wiper arms apply the circular cut tape segment to the edges of a mailer. This can be done while the edges of the mailer are stationary or moving parallel to the direction of the tape.

FIELD OF THE INVENTION 
This invention relates to a method and apparatus for applying a tab to the 
edges of a mailer. 
BACKGROUND OF THE INVENTION 
Mailers are today a well-known and common method of merchants transmitting 
their commercial messages to potential customers, usually at their places 
of residence. Typically a mailer will be formed from a cut segment of a 
continuous printed web of paper that is folded mid-length and has a tab 
applied to the edges of the sections parallel to the fold line. Normally, 
the tab will be made of paper and have an adhesive on the surface thereof 
which is affixed to the edges of the sections of the mailer which are 
parallel to the fold line thereby preventing each section from moving 
relative to the other section. 
With mailers being used in increasing volumes of numbers, it is important 
that one be able to apply the tab to the edges of the overlying sections 
of the mailer as rapidly as possible so that the cost of this step will be 
as inexpensive as possible. The prior art has recognized the need to apply 
tabs to the edges of products as well as certain other related fields of 
endeavor as evidenced by a number of prior art patents of which the 
inventors of the instant application are aware, to wit, the following: 
U.S. Pat. No. 3,545,670 
U.S. Pat. No. 3,898,122 
U.S. Pat. No. 3,939,034 
U.S. Pat. No. 3,960,646 
U.S. Pat. No. 4,009,070 
U.S. Pat. No. 4,208,976 
U.S. Pat. No. 4,235,031 
U.S. Pat. No. 4,394,206 
U.S. Pat. No. 4,504,336 
U.S. Pat. No. 4,598,860 
U.S. Pat. No. 4,824,427 
U.S. Pat. No. 4,869,775 
U.S. Pat. No. 4,944,720 
It is further noted that current postal regulations mandate the application 
of one or two tabs to the edges of a mailer, with the number of tabs 
determined by the weight of the mailer. Current available equipment does 
not satisfactorily perform this function. 
SUMMARY OF THE INVENTION 
It is therefore an object of the present invention to provide an improved 
method and apparatus for applying tabs to the overlying sections of a 
mailer. 
Briefly, the foregoing and other objects are accomplished by having a spool 
of pressure-sensitive tape fed through a tape slot of a tape guide block. 
The tape is wound upon a driven wind-up spool. A pneumatically driven (or, 
if desired, solenoid driven) punch and die arrangement is positioned so 
that upon actuation, the die cuts a circular (or other shape) segment of 
the tape and wiper arms apply the circular cut tape segment to the edges 
of a mailer. This can be done while the edges of the mailer are stationary 
or moving parallel to the direction of the tape.

DESCRIPTION OF THE PREFERRED EMBODIMENTS 
In FIG. 1 of the drawings, a tab applicator 10 according to the present 
invention is shown and includes a feed spool 12. Spool 12 rotates about a 
fixed shaft 14 and wound around spool 12 is a tape 16 which has a 
pressure-sensitive adhesive 20 on one side--to wit, the side which is in 
contact with the segment of tape immediately interior to it. The type of 
pressure-sensitive adhesive that can be used will be apparent to those 
having ordinary skill in the art. 
Alternatively, a water (or other ingredient) activated adhesive can be 
used, with the adhesive activating ingredient being conventionally applied 
to the adhesive on the tab prior to the tab being cut from the strip. 
Tape 16 is passed about an idler roller 22 which idler roller guides the 
tape 16. Idler roller 22 is freely rotatable about idler roller guide 
shaft 24 which is affixed to housing 26. 
From idler roller 22 tape 16 passes between guide roller 28 and knurled 
roller 30. Guide roller 28 is an idler roller and rotates about an guide 
roller support shaft 32 which is affixed to housing 26. 
Knurled roller 30 is a driven roller with the drive means therefor not 
being shown in the drawings. Knurled roller 30 is driven by knurled roller 
drive shaft 34 which is driven by drive means that is not visible in the 
drawings. Tape 16 passes through a tape slot 36 in a tape guide block 38 
where a circular tab is cut therefrom, as will hereinafter be described. 
From tape slot 36 tape 16 passes around an idler guide roller 39 which is 
freely rotatable about guide roller support shaft 40 which guide roller 
support shaft is affixed to housing 26. From passing about idler guide 
roller 39 tape 16 is wrapped about driven take-up spool 42 which take-up 
spool includes a drive shaft 44. Means are provided to rotate drive shaft 
44 and take-up spool 42 so that as take-up spool 42 rotates, the tape is 
wound thereabout. 
Still referring to FIG. 1 of the drawings, a pneumatically driven piston 
and cylinder arrangement 46 is illustrated between end plates 48 and 50. 
Piston and cylinder arrangement 46 specifically includes a cylinder 52 
within which is located a piston which is double acting. Air lines 54 and 
56 are connected respectively to end plates 48 and 50 and control the 
application of pressure or vent to the opposite sides of the piston. The 
piston located within a cylinder 52 is a double acting piston in that it 
can be driven under the influence of pressurized air in either of two 
opposed directions. It is to be appreciated that while a piston and 
cylinder arrangement have been shown for practicing the present invention, 
a solenoid arrangement can be utilized if desired. 
As can be seen in FIG. 1, a piston rod 58 extends through end plate 48 and 
can move in either of two opposed directions in conjunction with movement 
of the piston within cylinder 52. 
Piston rod 58 at its left end, which is visible in FIG. 1, is internally 
threaded and the right end of a rod 60 (FIG. 3) has external threads which 
are threaded into the internal threads of piston rod 58. A lock nut 62 
abuts against the left face of piston rod 58 and is tightened thereagainst 
to prevent undesired rotation of rod 60 relative to piston rod 58. 
Affixed to rod 60 (FIG. 1) is a spring collar 64 and the means of affixing 
collar 64 to rod 60 can be conventional. A compression spring 66 has one 
end abutting against spring collar 64, surrounds rod 60 and has its other 
end abutting retaining Ring 68 mounted in a grove on cylindrical barrel 
98. The free end on the leftmost portion of compression spring 60 is 
fixedly received within an opening in collar 68 as can be seen in FIG. 3. 
The collar 68 is received within an annular slot 70 of punch member 72. 
The left end of rod 60 can best be seen in FIGS. 2 and 3. Located at the 
left end of rod 60 on the top portion is a position slot 74 which extends 
parallel to the longitudinal axis of rod 60. A position hole 76 extends 
from one side of rod 60 perpendicular to the longitudinal axis thereof 
through the other side and serves a purpose that will hereinafter be 
described. An internal slot 78 is at the leftmost portion of rod 60. A tab 
wiper mechanism 80 is provided and can be seen in FIG. 2 as well as 
various other figures. The tab wiper mechanism includes wiper blades 82 
and 84 which are made of spring steel. Inasmuch as the wiper blades are 
identical to each other except for their orientation, a description of one 
wiper blade will suffice for an understanding of the present invention. 
Wiper blade 82 includes flat sections 86 and 88 which are angled with 
respect to each other. The portion of flat section 86 that is furthest 
from flat section 88 is received within slot 78 and together with the 
corresponding portion of wiper element 80 is secured within slot 78 by a 
lock (or roller) pin 90 which extends therethrough and can be seen in FIG. 
3. (In the embodiment of FIG. 14, two lock pins are utilized, with the 
second lock pin identified by reference numeral 91.) Lock pin 90 extends 
through the forward portion of rod 60 and through both segments of the 
wiper mechanism to secure the wiper mechanism relative to the rod. The 
forward portion of wiper blade 82 is defined by a wiper head 92 which is 
flared outwardly relative to flat section 88 while having the distal end 
thereof wrapped around itself. The wrapping around of the distal end of 
the wiper blade is optional and not mandatory for the practice of the 
present invention. 
Punch member 72 includes a cylindrical barrel 98 and a cutting die head 
portion 100. Cylindrical barrel 98 includes a longitudinal top slot 101 
and longitudinal opposed side slots 103, only one of which can be seen in 
the drawings. Die head 100 intersects with cylindrical barrel 98 at 
shoulder 102. The forward end of die head 100 includes a cutting die 104 
which die has an opening 106. Opening 106 is defined by an upper arcuate 
cutting edge 108 and a lower arcuate cutting edge 110 with the rear 
portion of the respective arcuate cutting edges intersecting with each 
other. As can be seen in FIG. 3, the forward portion of rod 60 from which 
wiper blade mechanism 80 extends is received within cylindrical barrel 98 
with the wiper head received within die head 100. 
A screw 112 includes a position pin 114 at its bottommost portion. Screw 
112 is screwed through a threaded opening 116 in tape guide block 38 with 
pin 114 extending through slots 101 and 74 to prevent rotation of each of 
the members which include said slots about their longitudinal axis and 
limit their travel. It is noted that slot 101 is of a lesser length than 
slot 74. Nut 118 is a lock nut and by abutting against tape guide block 38 
prevents lock screw 112 from freely rotating. 
A lock pin 120 (FIG. 2) extends through slots 103 and hole 76 so that 
relative rotation of the punch and die and rod 60 members is prevented. 
Guide block 38 includes a stepped internal bore having a shoulder 41. 
In FIGS. 2, 3, 4 and 5 of the drawings (as well as other figures), the 
folding mechanism for a tab is illustrated. A position pin 130 extends 
through tape guide block 38 in a vertical and direction surrounding said 
position pin is a coiled spring 132 having spring arms 134 and 136. Spring 
arm 136 normally will extend into opening 140 of block 38 and spring arm 
134 abuts said guide block such that spring arm 136 can be rotated in a 
clockwise direction as viewed in FIG. 4 out of the path of travel through 
opening 140. Spring 132 is positioned within a horizontal slot 144 (FIG. 
2) which slot is on one side of opening 140 of block 38. In a similar 
fashion, a position pin 146 extends through block 38, as can be seen in 
FIG. 2, through a slot 148 which is on the other side of opening 138 as is 
slot 144 and through the bottom portion of block 38. Received within slot 
148 is a spring 150 which has a spring arm 152 and a further spring arm 
154. Spring arm 136 and 152 extend into opening 140 and upon a force being 
applied to each of the spring arms in a direction of right to left as 
viewed in FIG. 4, the spring arms 136 and 152 will assume the dotted 
positions respectively shown for these spring arms. 
A female die 141 is formed on the inside part of opening 140 and can be, if 
desired, designed for removal and replacement when wear necessitates the 
replacement. 
The operation of the present invention will now be described. 
Spool 12 will be loaded with pressure-sensitive tape which will pass about 
idler roller 22 between idler roller 28 and driven knurled roller 30 
through slot 36 of guide block 38 about idler roller 39 and onto take-up 
spool 42. Take-up spool 42 is driven, as is knurled roller 30, so as to 
ensure tape 16 is advanced through the mechanism at a proper rate of 
speed. A folded over mailer will be advanced so that the edges of the 
mailer parallel to the fold line pass immediately adjacent slots 144 and 
148 while being parallel to a plane extending through said slots. Normally 
a mailer transport mechanism will position a mailer so that its edges 
which are parallel to the fold line are immediately adjacent slots 144 and 
148 where it will be held stationary while a tape is applied thereto. 
Alternatively, the tape can be applied to the edges of the mailer on the 
fly--i.e., as the mailer is moving past slots 144 and 148. 
When the edges of the sections of the mailer opposite the fold line are 
immediately adjacent slots 144 and 148 while being parallel thereto, 
initially the piston in cylinder 52 will be in the retracted rightmost 
position. Upper arcuate cutting edge 108 and lower arcuate cutting edge 
110 of die 104 will be spaced from tape 16, as shown in FIG. 3. Spring 66 
will not be under compression. In addition, punch and die member 72 will 
be in the position shown in FIG. 3 and rod 60 will be in its rightmost 
position such that pin 114 will be abutting the left portion of slot 74 
and the left portion of slot 102. 
At this time, pressurized air will be directed through line 56 to the right 
end of cylinder 52 while line 54 will be vented. A conventional valve can 
be used to control the flow of pressurized air to and from lines 54 and 
56. 
As pressurized air is directed through line 56, the piston within cylinder 
52 is moved to the left causing rod 58 and rod 60 likewise to move to the 
left. Initially, spring 66 will not be compressed but will assume the 
position shown in dotted lines in FIGS. 3 and 4, at the end of the stroke 
of the cylinder. Before the spring assumes the position shown in dotted 
lines in FIGS. 3 and 4, the upper arcuate cutting edge 108 and the lower 
arcuate cutting edge 110 of punch member 72 will take the position shown 
in FIG. 8--i.e., cut a circular tab from a pressure sensitive adhesive 
tape 16 against die 141. The further application of pressurized air to 
line 56 will result in the gradual compression of spring 66 with the punch 
member 72 going from the position in FIG. 8 to the position in FIG. 9 and 
as the spring compresses, the wiper blade mechanism 80 will move from the 
position of FIG. 8 to the position of FIG. 9 in opening 140. At this time, 
the cut tab will, as a result of the cutting action, be folded over 
against opposed spring arms 136 and 152 which point directly at each other 
while extending into opening 140. This will cause a fold line in the cut 
tab. Further pressurization of line 56 will result in the punch and die 
member and wiper blades assuming the position shown in FIG. 10. At this 
time, it is important to keep in mind that pin 114 and retaining Ring 68 
will limit further movement of punch member 72 to the left while allowing 
further movement of rod 60 to the left. The wiper mechanism as seen in 
FIG. 10 will wrap the tab around the edges of the mailer while moving the 
spring fingers out of opening 140 such that spring finger 136 rotates in a 
clockwise direction as viewed in FIG. 4 to the position shown in dotted 
lines while spring finger 152 assumes the position shown in dotted lines 
by rotating in a counterclockwise direction as seen in FIG. 4. 
The inherent resiliency of wiper blades 82 and 84 will press the tab 
against the edges of the mailer so that the adhesive will adhere thereto, 
as seen in FIG. 11A. 
At this time, pressure will be released from line 56 directed to line 54 
and the mailer with the tab applied to the edge will be moved from the 
position shown in the figures away from slots 144 and 148 and a new mailer 
edge positioned thereon. As pressure is directed to line 54, the mechanism 
will first take the position seen in FIG. 11 and gradually be restored to 
the position seen in FIG. 3 and the tape drive mechanism will advance the 
tape so that the tab that is immediately adjacent to the upper and lower 
arcuate cutting edges does not have any portions removed therefrom. To 
accomplish this an intermittent tape drive is provided which is 
conventional. During the retraction of the punch and die mechanism, spring 
finger 136 will rotate in a counterclockwise direction and, as viewed in 
FIG. 4, will assume the position shown in solid lines in FIG. 4. Spring 
finger 152 will rotate from the position shown in dotted lines in FIG. 4 
clockwise to the position shown in solid lines in FIG. 4 and the cycle can 
then be repeated. 
In FIGS. 12-14, alternate embodiments of the invention are shown which are 
identical to the previous embodiments but include a cutting instrument. In 
the FIG. 12 embodiment, the punch member 72 is composed of a separate 
cutting head portion 302 and a barrel portion 304. Barrel portion 304 
includes a circular extension 306 having opposed slots 308 and 310. 
Circular extension 306 is snugly fit within cutting head portion 302 such 
that cutting head portion 302 and barrel portion 304 move in unison with 
each other. A cutting blade 300 extends through head portion 302 and the 
rear portion of cutting blade 300 is snugly fit and secured in slots 308 
and 310. The forward portion of cutting blade 300, as viewed in FIG. 12, 
includes edge cutters 312 and 314, with each edge cutter including a 
pointed cutting tip which pointed cutting tips are identified by reference 
numerals 316 and 318. 
Cutting blade 300, as can be seen in FIG. 14, extends between the wiper 
blades 82 and 84 and serves the function of perforating the edges of a cut 
tab so that the tab while being strong enough to secure the edges of a 
mailer will not be so strong that when the sections of the mailer are 
pulled apart to be separated from each other, the mailer will rip and not 
the tab. 
In FIG. 13, an alternate cutting blade 400 is seen which is identical to 
cutting blade 300 except the cutting edges are formed by a plurality of 
cutting teeth 402 with each cutting tooth having a pointed cutting tip 
which is flanked on opposite sides by a cutting edge. The result of using 
the cutting blade of FIG. 13 is that a perforated tab as seen in FIG. 13 
is obtained. 
In FIG. 15 of the drawings, an alternate embodiment of the present 
invention is shown wherein cylindrical barrel 98 and cutting head portion 
100 are not of one-piece construction. In all other respects, the FIG. 15 
embodiment is identical to the earlier described embodiments, except as 
described herein. Cutting head portion 100 does not include on its outside 
surface a cylindrical area of a constant cross-section as with the 
previous embodiments of the present invention. Cutting head 100 has a 
smaller diameter than the inside surface of guide block 38 so there is a 
gap between the external surface 100a of the cutting head and the interior 
surface of the guide block. As a consequence, when the adhesive 
accumulates in this gap, there is space to accommodate the adhesive so 
that the same does not result in such high friction between the external 
surface of the cutting head and the interior surface of the guide block 
such that it is difficult to move the guide block cyclically back and 
forth. Cylindrical barrel 98 is affixed to cutting head 100 by means of 
screws that are 180 degrees apart from each other and one of which can be 
seen in FIG. 15 and which is identified by reference numeral 103. The 
screws allow the cylindrical barrel to separate from the cutting head 100 
so that as wear necessitates the replacement of the cutting head this can 
be simply done. 
While this invention has been shown and described in connection with 
particular preferred embodiments, various alterations and modifications 
will occur to those skilled in the art. Accordingly, the following claims 
are intended to define the valid scope of this invention over the prior 
art, and to cover all changes and modifications falling within the true 
spirit and valid scope of this invention.