Device for transferring and monitoring load to die roll

A device for transferring and monitoring the load applied to a die cutting roll in a press has a pressure indicator for registering applied force. By utilizing an elongated member having such a pressure indicator adjacent each of its opposite ends, or by utilizing two such devices with an assist roller mounted therebetween, the force applied to the opposite ends of the underlying die roll can readily be determined, and adjusted if necessary. The load-bearing members of the device preferably comprise a diaphragm mounted on the body in sealing relationship over a recess, to which the pressure indicator is operatively connected.

BACKGROUND OF THE INVENTION 
The die rolls utilized for continuous rotary die cutting of web materials 
must be manufactured with a high degree of accuracy, to ensure smooth and 
true running in the die-cutting press and to produce work of good quality 
over extended periods of time; such rolls are therefore quite expensive. 
It is moreover essential that the die cutting roll be accurately 
positioned in the press and subjected to balanced loading, since otherwise 
performance will be unsatisfactory and the rate of die wear will be 
excessive. 
Such rotary dies normally consist of a cylindrical body portion with 
annular bearers at the opposite ends. The bearers cooperate with the 
underlying base or anvil roll to maintain proper clearance between the 
cutting edge of the die roll and the anvil roll surface. Whereas it is 
practical to precisely machine the die itself, inaccuracy is often 
introduced in setting-up the press, or develops during operation, because 
the opposite ends of the roll are subjected to unequal forces. 
Accordingly, it is the primary object of the present invention to provide a 
novel device for transferring and monitoring the load applied to a die 
cutting roll so as to balance the forces transmitted thereto, to thereby 
achieve improved performance and prolonged die life. 
It is also an object of the invention to provide such a device which can be 
utilized both during the setting-up procedure and also during operation of 
the press, to establish and maintain the desired balanced load upon the 
die roll. 
Another object of the invention is to provide such a device which is 
relatively simple in design and inexpensive to manufacture, and which is 
nevertheless convenient to employ and highly effective for its intended 
purposes. 
SUMMARY OF THE INVENTION 
It has now been found that the foregoing and related objects of the 
invention are readily attained in a device for transferring and monitoring 
the load applied to a die cutting roll in a press, comprising a body 
adapted for mounting in the press, having load-bearing and 
pressure-indicating means therein. The means employed includes a 
load-bearing member disposed on one side of the body, for contact by 
force-applying means of the press, and a pressure indicator operatively 
connected to the load-bearing member. Means is also present on the body 
for transferring the applied force to a die cutting roll, mounted in the 
press to the side of the body opposite to that on which the load-bearing 
member is disposed. 
In the preferred embodiments, the body will have a cavity formed into its 
"one" side and in fluid flow communication with the pressure indicator, 
and the load-bearing member will comprise a diaphragm mounted on the body 
in sealing relationship over the cavity, to provide a substantially closed 
chamber. The diaphragm will most desirably be a metal disc having a 
central boss and a circumferential shoulder portion, both defined by an 
annular recess formed into one side of the disc. The annular recess will 
provide a relatively flexible web portion, which will permit resilient 
displacement of the boss relative to the shoulder portion and into the 
chamber. Generally, the body will have a bore extending into the cavity, 
and the device will additionally include a piston mounted within the bore 
to seal it against fluid flow; the position of the piston in the bore will 
be adjustable to control the level of pressure within the chamber. 
In certain embodiments, the body of the device will be an elongated block 
that is dimensioned and configured for mounting between the frame portions 
of the press, across the die cutting station thereof. In such instances, 
the load-bearing and pressure-indicating means will include a second 
load-bearing member and pressure indicator, disposed and connected as 
previously described, but with one of the load-bearing means adjacent each 
of the opposite ends of the block. Thus, the block will be adapted to 
receive a two-point force load, and to balance the forces transferred 
therethrough. 
In some cases, the body will be adapted for use with an assist block 
interposed in the press between it and the die cutting roll, with the 
force-transferring means comprising the "opposite side" surface thereof. 
Alternatively, it may be designed for use alone, in which instance the 
force-transferring means will normally be adapted for establishing direct, 
rolling contact with the die cutting roll. As yet another alternative, the 
body will have an opening extending transversely thereinto from one side, 
to receive an end portion of an assist roll comprising the 
force-transferring means; a pair of such bodies will be used to support 
the opposite ends of the assist roll therebetween.

DETAILED DESCRIPTION OF THE ILLUSTRATED EMBODIMENTS 
Turning now in detail to FIG. 1 of the drawings, therein illustrated is a 
die cutting press in which is installed a die cutting roll, generally 
designated by the numeral 10, and a force monitoring device embodying the 
invention, generally designated by the numeral 12. Both are supported at 
their opposite ends by the side frame portions 14 of the press, across 
which extends a die pressure bridge, generally designated by the numeral 
16, bolted thereto. 
The die cutting roll 10 is of standard construction, and consists of a 
cylindrical body portion 18 on which is formed a cutting element 20, and 
adjacent each of the opposite ends of which is affixed an annular bearer 
22. A gear for driving the die roll 10 is also affixed at one end of the 
shaft 26, and suitable bearing blocks 28 are provided for journalled 
support of the shaft 26 in the frame portions 14. 
Although details of construction will be discussed more fully in connection 
with the subsequent figures, it will be noted in FIG. 1 that the 
monitoring device 12 consists of an elongated block body 30, in which is 
rotatably supported a pair of pressure rolls 32 for rolling contact with 
the bearers 22 of the die cutting roll 10. A pair of pressure gauges 34 
are mounted on the body 30, and sensing caps, generally designated by the 
numeral 36, are disposed in the upper portion thereof in position beneath 
the die pressure screws 38; the latter are, in turn, mounted within the 
cross-piece 40 of the pressure bridge 16. 
As will readily be appreciated, force applied by the two pressure screws 38 
is transmitted to the die cutting roll 10 through the load monitoring 
device 12. One of the screws 38 is aligned over one of the pressure rolls 
32 and one of the bearers 22 adjacent each of the opposite ends of the 
assembly; therefore, the forces exerted by the screws 38 must be 
substantially the same if the load across the die cutting roll 10 is to be 
balanced. 
In accordance with the present invention, this is easily accomplished due 
to the fact that the gauges 34 provide an accurate indication of the 
magnitude of force applied to each of the sensing caps 36 by the screw 38 
that acts upon it. By merely matching the pressure readings of the two 
gauges, the forces applied and transmitted to the die cutting roll 10, 
through the rolls 32 and the bearers 22, are readily balanced. 
Although the monitoring device 12 illustrated in FIG. 1 may be regarded as 
incorporated in the body of an assist block, this need not be the case; 
the device 42, shown in FIG. 2, is a separate unit, that is designed for 
use in cooperation with a standard assist block 44. In terms of force 
monitoring and transmitting effects, the combination shown in FIG. 2 
functions in virtually the same manner as does that of FIG. 1, and the 
details of construction shown are commonly applicable. Consequently, the 
same numbers are employed, where appropriate, to designate parts that are 
common to both embodiments. As will be appreciated, one of the pressure 
rolls 32 is removed from the unit shown in FIG. 2, for clarity of 
illustration. 
The device 42 consists of an elongated plate 46, into the upper surface of 
which is formed a pair of compound cavities generally designated 48 (only 
one of which is visible), consisting of a lower chamber 50 and an upper 
annular portion 52. A pressure-sensing cap, generally designated 36, is 
seated within each of the compound cavities 48 with its bottom surface 54 
in contact with the annular surface 56; the surface 54 has a circular 
groove 58 formed in it to receive the sealing ring 60, which bears upon 
the surface 56 to prevent leakage from the underlying chamber 50. 
The cap itself consists of a central boss or button 62 and a 
circumferential shoulder portion 64, which are defined by an annular 
recess 66 formed therebetween. This produces an annular web portion 68 at 
the bottom of the recess 66, which is sufficiently thin to function as a 
pressure-responsive diaphragm. As will therefore be appreciated, force 
applied to the button 62 from the screw 38 will be transmitted to the 
plate 46; it will be also cause a slight deflection of the annular web 68, 
thereby increasing the pressure within the chamber 50. 
The latter is connected to the corresponding guage 34 by one leg 70 of a 
passageway formed in the plate 46, with a hydraulic fluid filling the 
interior spaces. Thus, the magnitude of force applied by each of the two 
screws 38 to the opposite ends of the plate 46 will be caused to register 
on the associated gauges 34, thereby permitting the load across the plate 
46, and hence upon the underlying die roll, to be readily balanced by 
observing the readings on the two gauges 34 as the pressure screws 38 are 
adjusted. 
As will be noted, the plate 46 has threaded apertures 74 formed thereinto, 
which receive four fasteners 76 to secure the caps 36 against disassembly. 
Each of the gauges 34 has a threaded nipple 77 on its mounting structure, 
which is engaged within a corresponding aperture 75 formed into the front 
surface of the plate 46. The internal construction of the plate 46, 
defining the hydraulic system by which the applied pressure is transmitted 
to the gauges 34, is best shown in FIGS. 3 and 4. 
As can be seen therein, the chamber 50 is connected to the gauge 34 through 
the tangentially extending leg 78 and the connecting leg 70 of the 
internal passageway. The tangential leg 78 opens to an enlarged 
cylindrical section 80 which, in turn, joins a threaded outer portion 82; 
the latter terminates at the rear edge 84 of the plate 46. A piston, 
generally designated by the numeral 86, is slidably received within the 
cylindrical intermediate section 80 of the passageway, and has a pair of 
sealing O-rings 88 mounted in circumferential grooves 90 extending 
thereabout. A threaded adjustment screw 92 is engaged within the outer 
section 82 of the passageway, behind the piston 96 and in direct contact 
therewith. 
The level of pressure on the hydraulic fluid contained within the chamber 
50, and within the legs 70, 78 and intermediate section 80 of the internal 
passageway, is readily set to a predetermined value, by suitable 
adjustment of the screw 92. For example, the screw may be adjusted until 
the gauge 34 associated with that part of the system registers a zero 
pressure value. It will be appreciated that both halves of the system will 
normally be adjusted to cause the gauges to read the same in the absence 
of external force, and that the actual pressure level within the hydraulic 
system will not generally be of concern. The significant factor is, of 
course, that the gauges be calibrated to one another, so as to enable the 
increase in pressure on each side of the device 42 to be accurately 
monitored and matched, to enable a facile balancing of the forces applied 
by the screws 38. 
Turning finally to FIGS. 5 and 6, a third embodiment of the devices of the 
invention is illustrated, and once again parts thereof that are common to 
the embodiments of the foregoing figures bear the same numbers. In this 
instance, two separate blocks, each generally designated by the numeral 
94, are utilized to support therebetween an assist roller, shown in 
phantom line and generally designated by the numeral 96. For this purpose, 
each block has a relatively large bore 98 extending transversely 
therethrough, in which is journalled one of the ends of the roll 96; a 
set-screw 100, received in an elongated threaded aperture 101 extending 
inwardly from the rear of the block 94, bears upon a surface flat and 
retains the end of the roller in position therewithin. 
Although a similar piston 86 and cooperating adjustment screw 92 are used 
in each of the blocks 94 to adjust the pressure within the chamber 50 
beneath the cap 36, in this instance the configuration of the internal 
passageway is somewhat different, to accommodate the difference in the 
design and construction of the load monitoring device itself. More 
particularly, the two legs 70, 78 thereof are axially aligned, and extend 
substantially from the front to the rear of the block 94, with the chamber 
50 disposed therebetween. Nevertheless, it will be appreciated that the 
assembly of FIG. 5 will be used and will function in substantially the 
same manner as the devices heretofore described. The force applied by the 
screws 38 to the caps 36 on each of the blocks 94 will be transferred to 
an underlying cutting roll 10 by the assist roll 96, through its end 
bearers 102, with the levels of force applied at each end of the assembly 
being indicated by the two gauges 34. 
Although three embodiments of the present device, and specific arrangements 
of the parts thereof, have been illustrated, it will be appreciated that 
changes and substitutions can be made without departing from the concepts 
of the invention. For example, while specific forms of pressure sensing 
and indicating devices have been described others, such as of a digital or 
like electronic nature, might be employed instead. Also, while the primary 
function of the present apparatus is to facilitate balancing of the 
applied forces, it may also be used as a pressure indicating device, in a 
more absolute sense. For example, by designating a maximum permissible 
reading for the pressure indicators, overloading of the die can be 
prevented. 
Thus, it can be see that the present invention provides a novel device for 
transferring and monitoring the load applied to a die cutting roll, so as 
to balance the forces transmitted thereto, to thereby achieve improved 
performance and prolonged die life. The device can be utilized both during 
the setting-up procedure and also during operation of the press, to 
establish and maintain the desired balanced load upon the die roll. The 
device is of relatively simple design, convenient to utilize, and 
inexpensive to manufacture, and is nevertheless highly effective in 
achieving the objectives of the invention.