Gummer roll apparatus

A gumming roll preferably for use with apparatus for applying gum to blanks and pertains, has rollers in skidding contact for returning excess adhesive to an adhesive pan without substantial foaming of the adhesive.

BACKGROUND OF THE INVENTION 
The present invention relates in general to a gumming roll apparatus for 
applying gum to blanks and pertains, more particularly, to an apparatus 
for applying gum to envelopes during continuous processing and operation 
of a gumming machine. The roller combination of this invention is an 
improvement over the conventional low speed gumming station roller 
combination. 
With the conventional gumming roll apparatus a gumming station is typically 
one of a number of stations in an envelope processing apparatus or other 
continuous processing apparatus. For example, it is common to provide a 
gumming station in a conventional envelope making machine or in apparatus 
intended to apply gum (e.g., a self-sealing latex adhesive) to envelopes 
already formed and processed solely for the purpose of applying a desired 
adhesive. 
Self-sealing envelopes typically require cooperating adhesive deposits 
applied to both a flap and an enclosure portion of an envelope. The 
envelope is gummed in order that a sealed envelope will be formed when the 
adhesive carrying portions are pressed together. It will be understood 
that other articles, forms, or enclosures may be processed in an 
equivalent manner. 
The conventional gumming stations typically satisfy the operational 
requirements with a combination gum box, roller for transferring the gum 
or adhesive to one or more gummer pads on a gummer roll. The conventional 
apparatus includes the gum box or trough for supplying the adhesive of 
choice, one or more intermediate transfer rollers for transferring the 
adhesive to the adhesive application roller. 
These conventional roller arrangements provide for the physical transfer of 
the adhesive as rotation of the roller carries the roller surface through 
the gum box and the adhesive which agitates the adhesive. Typical 
adhesives, particularly latex adhesives, foam or froth as a consequence of 
agitation. 
It is a known drawback of gumming apparatus that the foam or froth may be 
transferred on the rollers to the envelope or other adhesive receiving 
portion of an article processed at the gumming station. The foam or froth 
creates a blemish on the adhesive which may not provide a desired 
adherence. It is typical to reject items with this foam or froth blemish. 
As a result, conventional gumming stations and apparatus have a drawback 
of a limited speed of operation. 
The gumming station speed limitation creates an overall equipment 
limitation since the transfer roller must operate at a speed sufficient to 
transfer adhesive to the gumming roller and the latter roller rotates in a 
manner to provide registration between gummer pads and items passing 
through the gumming station. 
Reducing the rotational speed of a gumming roller without reducing the 
processing speed or output of the gumming station would require a 
relatively large gumming roller circumference with a limited rotational 
speed in conventional apparatus. This solution has numerous drawbacks, 
including space limitation since the gummer station is often one of a 
number of stations. Another drawback associated with a larger and slower 
gumming roller is that the adhesive could dry out between applications of 
fresh adhesive from the transfer roller. 
Accordingly, it is an object of the present invention to provide an 
improved gum roll apparatus that is adapted to increase the processing 
speed of a gumming station. With the roller arrangement of this invention 
the gumming station output of either a stand alone station or a gumming 
station incorporated into a larger apparatus will be increased without 
significant adhesive degradation due to foam or froth transferred to a 
workpiece from the gumming roller. 
Another object of the present invention is to provide an improved gum roll 
apparatus that is constructed to provide a more uniform adhesive transfer 
with an increase in gum roller rotational speed and thus provide an 
increased output for an apparatus incorporating the arrangement of this 
invention. 
A further object of the present invention is to provide an improved gum 
roll apparatus that is adapted for use with existing equipment. The 
improved roller combination of this invention may be incorporated into 
existing equipment with only minor timing modifications to ensure that the 
adhesive is applied in desired registration with the envelope flap, or the 
like. 
Still another object of the present invention is to provide an improved gum 
roll apparatus that may be readily adapted for use in a gumming machine 
for applying adhesive to envelope flaps. 
Still a further object of the present invention is to provide an improved 
gum roll apparatus that allows an increase in gummer cylinder rotational 
speed without a corresponding increase in adhesive foaming. The 
combination of this invention substantially eliminates adhesive or gum 
foaming on the gummer cylinder and associated gummer pads. 
SUMMARY OF THE INVENTION 
To accomplish the foregoing and other objects of this invention there is 
provided an gum roll apparatus and gumming roll combination for 
transferring adhesive from a gum box to a receiving piece, such as an 
envelope flap. The gum roll apparatus and gumming roll combination 
comprises an adhesive reservoir means and a plurality of operatively 
associated transfer means. 
A portion of the adhesive means is transferred from the reservoir means to 
a workpiece. The skidding of one roller on another effectively removes and 
returns the adhesive to a pan without causing foam or froth in the pan at 
slow operating speeds and significantly reducing foaming and frothing at 
relatively higher operating speeds and returns excess adhesive material to 
the reservoir with a minimum of foaming of the adhesive in the reservoir. 
The transfer means may include first and second roller means. 
Another roller means is in wiping contact with the first roller means. The 
wiping contact results in the transfer of a non-turbulent portion of the 
adhesive means from the first roller means to the second roller means. 
A third roller means is in operative contact with the adhesive carried on 
the second roller means. A portion of the adhesive is transferred from the 
second roller means to the third roller means and then to a designated 
portion of the receiving piece or workpiece. 
A method of the present invention includes the steps of providing an 
adhesive means in a container and rotating a first roller means through 
the adhesive means in the container. A second roller means is rotated in 
the opposite direction and skids over the first roller means with the 
second roller means returning an excess of the adhesive means to an 
adhesive reservoir with reduced foaming. 
These and other objects and features of the present invention will be 
better understood and appreciated from the following detailed description 
of one embodiment thereof, selected for purposes of illustration and shown 
in the accompanying drawings.

DETAILED DESCRIPTION 
Referring now to the drawings there are shown preferred embodiments for the 
gum roller and gum roller combination incorporating the meter and skidding 
or wiping roll of this invention. The wiping roll is described in 
connection with an envelope making application to apply adhesive to an 
envelope construction. The wiper roll of the present invention is 
particularly adapted for providing a homogeneous adhesive layer on the 
envelope and is characterized by the isolation of foam or froth from the 
adhesive applied to the envelope. 
The drawings show a conventional gumming apparatus 10 including a conveying 
station 12, a workpiece or envelope transfer station 14, a flap bending 
station 16, and a gumming station 18. The gumming apparatus includes 
horizontal supporting framework members 20 and vertical supporting 
framework members 22. 
The workpiece 28, e.g., an envelope is transferred through the gumming 
apparatus 10 on a conventional conveyor table 24 while it is maintained in 
a generally flattened position by longitudinal hold down members 26 placed 
as required along the length of the gumming apparatus. The envelope 28 
depicted in FIG. 1 includes a single gum or adhesive receiving flap 30. 
The conventional transfer station 14 includes a power take off mechanism 
and its associated housing 32. The particular power take off will vary 
depending upon the method used to supply motive power to the various 
stations along the length of the apparatus 10. A chain drive, belt drive, 
or individual motors are suitable power sources. It will be understood by 
one skilled in the art as to how to provide the required power take off to 
the gumming apparatus stations. 
Referring again to the transfer station 14, there is provided the drive or 
gear housing 32 from which extends a drive shaft 34. A support member 36 
at the end of the drive shaft carries two vacuum supply outlets 38 and the 
vacuum is supplied from a suitable vacuum source (not shown) by a vacuum 
hose 40. The drive shaft rotates the outlets 38 in timed relationship with 
the envelopes 28 transferred through the gumming apparatus 10. A plurality 
of driven and non-driven transfer rollers 42 assist in the transfer and 
movement of the envelopes. 
The transfer station moves each envelope in turn to the flap bending 
station 16 and into cooperative association with receiving supports 44 
which guide each envelope to a flap bending member 46. In the illustrated 
embodiment a plough share bending device is depicted. It will be 
understood that other flap bending devices may be substituted. 
The gumming station 18 includes a drive or gear housing 48 for the desired 
power take off arrangement used in a particular gumming apparatus. As will 
be understood from the support arrangement, the gumming station of the 
present invention may be removed or added to a particular gumming 
apparatus. If the present invention is added to an existing apparatus, 
then those skilled in the art will recognize and understand the timing 
adjustments that may be required to integrate the gumming station as an 
operating portion of the overall apparatus. 
The drive or gear housing may also include a conventional adjustable drive 
or gear arrangement in order to adjust the rotational speed of the rollers 
(described below). Incorporation of an adjustable drive increases the 
flexibility of the gumming station to accommodate different operating 
requirements that the apparatus 10 is intended to provide. 
A gear housing 50 is provided and supported on a framework that permits 
removal of the entire gummer station as a unit, if desired. The framework 
includes vertical support members 52 and horizontal support members 54. A 
housing support member 56 is shown for the illustrated embodiment. 
The roller combination in the illustrated embodiment includes a gum (gum 
and adhesive are used interchangeably throughout) metering roller 58, a 
gum roller 60, a wiper roller 62, and a gummer cylinder 64. A roller 
support structure 66 provides shaft and bearing support for the rollers as 
required. 
A gummer cylinder drive or gear housing 68 is provided for the gear, drive, 
or power take off arrangement provided with the particular gummer 
apparatus 10. In the illustrated embodiment it is considered preferred to 
provide a chain drive (not shown) extending the length of the apparatus 
10. The chain will provide the source of power for drives at each station. 
The conventional gummer cylinder includes a drive shaft 70, spoke members 
72 (the spokes may not be required if the cylinder is constructed from a 
hollow cylinder with closed ends, not shown), and the gummer cylinder 
support surface or structure 74. The structure 74 carries a conventional 
gummer pad 76 and a flexible support sheet 78. 
The flexible sheet is typically held in place with strips of tape 80. Using 
tape allows the pads to be moved or changed. For example, it will be noted 
that one gummer pad is used in FIG. 1 and two gummer pads are used in the 
embodiment depicted in FIG. 2 because of the different envelope being 
processed. 
Another embodiment of the present invention is depicted in FIG. 2 and 
includes gummer station 18 and associated vertical support members 82 and 
horizontal support members 84. The horizontal members 84 can incorporate 
the required bearing supports for the roller support shafts. Suitable 
fasteners 86, such as machine bolts, hold the structure together and may 
be removed as required. The support structure supports an adhesive pan 88. 
A gummer roll support structure 90 including necessary bearings 92 provide 
support for the gummer cylinder 64. 
The gum and wiper roller combination 60, 62 are driven through a gum roller 
drive shaft 94 supported for rotation by a suitable shaft bearing 96. A 
shaft extension 98 extends to the support member 84. The metering roller 
58 is supported for rotation by support shaft 100 and associated support 
shaft bearings 102. Similarly, the wiper roller 62 is supported for 
rotation by its associated support shaft 104 and support shaft bearing 
106. Both the wiper and meter rollers are eccentrically mounted in 
preferred embodiment. 
The gum and meter roller combination 60, 58 are driven through the gum 
roller drive shaft 94 supported for rotation by the shaft bearing 96. 
Another workpiece 108 is illustrated and includes an enclosure portion 110 
and a flap portion 112. The enclosure is illustrated as having an adhesive 
receiving portion 114 and the flap has an adhesive receiving portion 116. 
This illustrates the flexibility provided by the gummer pads that can be 
removed and replaced. In FIG. 2 there is shown an enclosure gummer pad 118 
and a flap gummer pad 120 carried by a flexible support member 122. The 
support member is attached to the gummer cylinder with adhesive members 
124, 126, such as lengths of adhesive tape. 
A preferred embodiment of a wiper roll gear train 128 is depicted in FIG. 2 
and includes a gum roller gear 130 and an associated hub 132. It will be 
understood that the gears can be removed and replaced in order to allow a 
change in the gear ratios and rotational speed of the rollers. Likewise, 
the rollers can be changed if desired or required. A wiper roller gear 134 
and an associated hub 136 are eccentrically supported by structural 
support member 84 in a preferred embodiment. 
An intermediate gear 138 provides for the gum roller and the wiper roller 
to rotate in the same direction and opposite to the gummer cylinder. The 
intermediate gear includes an associated support shaft and hub combination 
140. 
A preferred embodiment of a meter roll gear train 160 is depicted in FIG. 4 
and includes a drive shaft gear 156 and a metering roller support shaft 
gear 158. In a preferred embodiment the gear 158 can be removed and it and 
associated shaft 100 are eccentrically mounted to member 84 by a suitable 
hub member (not shown). 
In operation, in connection with the gumming apparatus 10 previously 
mentioned, an adhesive carrying surface 142 of the gum roller 60 passes 
through the adhesive pan 88 and an adhesive 156 contained in the pan and 
carries a portion of the adhesive out of the pan. The metering roller 58 
is provided or adjusted to give a desired gap 144, thereby returning 
excess adhesive to the pan. A surface 146 of the metering roller 58 skids 
across the gum roller at a desired distance and returns excess adhesive to 
the pan 88. 
The excess adhesive returns to the pan 88 in what may be described as a 
waterfall of adhesive. In a preferred embodiment the meter roller is 
placed as near as possible to the surface of the adhesive 156. The closer 
to the surface of the adhesive, the less foaming and frothing that occurs. 
To better understand the foaming problem, typical latex adhesives are a 
white milky fluid that will foam when agitated much like an egg white when 
beaten. When adhesive foaming gets out of control it is typical that the 
foam and adhesive will overflow the pan 88. 
A typical adhesive pan is approximately 11/2" deep and the gum roll is 
placed within approximately 1/8" of the bottom of the pan 88. This should 
reduce foaming as the gum roller passes through the adhesive 156. 
The meter roller 58 rotates in the opposite direction as the gum roller 60 
and skids across the gum roller surface returning the excess adhesive to 
the pan 88. The meter roller eccentric adjustment allows the optimum 
skidding effect. The optimum adjustment of the meter and gum rollers has 
been observed to produce a corduroy effect whereby the adhesive remaining 
on the gum roller produces a series of parallel grooves on the gum roller 
and around the circumference of the gum roller. 
The wiper roller 62 rotates in the same direction as the gum roller 60. The 
present invention is intended to operate at roller speeds in excess of 
conventional rollers. In one embodiment the gum roller operates at a 
rotational speed of approximately 150 r.p.m. and a preferred gear train 
rotates the meter roll at approximately 38 r.p.m. and the wiper roll at 
approximately 300 r.p.m., while the gummer cylinder at approximately 150 
r.p.m. increases workpiece output since it sized in the illustrated 
embodiment to approximately twice the diameter of the wiper or the gum 
rolls. The wiper roll transfers the adhesive to the gummer cylinder in the 
corduroy or corrugated pattern when optimally adjusted on its eccentric. 
While specific embodiments have been shown and described, many variations 
are possible. The eccentric mounting of the gears and shafts is a 
preferred feature. However, since all of these members can be removed, 
then the desired adjustments can be accomplished by changing the gears and 
rollers. It will be understood that those skilled in the art have the 
ability to determine the desired roller diameters of eccentric adjustments 
to provide desired operation of this invention. 
Having described the invention in detail, those skilled in the art will 
appreciate that modifications may be made of the invention without 
departing from its spirit. Therefore, it is not intended that the scope of 
the invention be limited to the specific embodiments illustrated and 
described. Rather, it is intended that the scope of this invention be 
determined by the appended claims and their equivalents.