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Патент USA US3039724

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June 19‘, 1962
L. CAMPBELL ETAL
3,039,714
PNEUMATIC WEB CONTROL DEVICE
Filed Jan. 15. 1958
3 Sheets-Sheet 1
FLOATING
FIG. I
ROLLE
@
TENSION CYLINDER
PRESSU
BUILD -U
CYLI N DERS
INVENTORS
ALBERT L. PETERSON
LEONARD CAMPBELL
T m E o F sTm
EMQ‘IM’ %Jm,@amn‘¢
‘PA
A ZRNEYS
June 19, 1962
L_ CAMPBELL ETAL
3,039,714
PNEUMATIC WEB CONTROL DEVICE
Filed Jan. 15, 1958
3 Sheets-Sheet 2
FIG. 3
NTROL VALVE
I2
PER
AIR MOTOR
INVENTORS
ALBERT L. PETERSO‘
B
LEONARD CAMPBELL
ATTgRNEYS
June 19, 1962
' |_. CAMPBELL ETAL
3,039,714
PNEUMATIC WEB CONTROL DEVICE
Filed Jan. 15. 1958
5 Sheets-Sheet 3
INVENTORS
ALBERT L.PETERSON
LEONARD CAMPBELL
ATTOR EY S
I United States Patent O??ce
3,639,714
Patented June 19, 19-62
2
1
reference force air motor and is pulled in the opposite
direction by the tension of the web on the ?oating roller.
3,039,714
PNEUMATIC WEB CONTROL DEVICE
Leonard Campbell, New Brunswick, and Albert L. Peter
Movement of the arm will actuate the control valve to
allow air to be either exhausted from the tension cylin—
son, West?eld, N.J., assignors to Wood Newspaper
Machinery Corporation, Plain?eld, N.J., a corpora
tion of Virginia
Filed Jan. 15, 1958, Ser. No. 709,152
6 Claims. (Cl. 242-7542)
der or to be admitted thereto from a source of pressure.
Conduit means connect the reaction chamber of the
control valve either with the tension cylinder or with a
control pressure outlet port of the control valve so that
pneumatic pressure in the reaction chamber will cause
This invention relates generally to a pneumatic Web 10 the ?exible diaphragm to move and to compensate and
oppose the force necessary to actuate the control valve.
control device and more particularly to an automatic web
Rate of ?ow means are provided in the conduit for ad
tensioning device incorporating a ?oating roller for main
justing rate of ?ow of pressure air into the reaction cham
taining substantially constant tension in a running web,
ber in order that the period and amount of response be
pneumatic braking means actuated by movement of the
?oating roller for braking a rotating supply roll, and 15 tween application of braking force on the supply roll and
return of the control valve to its balance position may
rate means for adjusting the characteristics of response of
be varied. The overall effect of such a system is to ap
the brake means to the movement of the ?oating roller.
A prime requirement of high speed printing presses
ply an initially greater pressure in the tension cylinder
such as used in printing newspapers, is that the running
web of paper passing to the printing press be kept at a
substantially constant tension. If, for any reason, the
than is normally needed to maintain constant tension.
Referring to the drawings which illustrate a preferred
embodiment of our invention,
FIG. 1 is a schematic view illustrating the position of
the different parts of the web tensioning device with re
tension of the web increases considerably, there is danger
that the Web will break. On the other hand, if the ten
spect to supply rolls;
sion of the web decreases below a predetermined value,
FIG. 2. is a graph illustrating pressure built up in the
there is danger that the web will bunch up before enter 25
tension cylinder with regard to receipt of a stop signal
ing the press. This latter condition will usually occur
by the press;
when the web is supplied from a rotating supply roll,
FIG. 3 is an enlarged side view of the ?oating roller
which, due to its heavy mass, will tend to run ahead of
and associated parts shown in FIG. 1;
the press if the press speed drops suddenly and if the
?oating roller and tensioning device are incapable of 30 FIG. 4 is an enlarged cross-sectional view of the con
trol valve shown in FIG. 3; and
overcoming the change in tension of the running web.
FIG. 5 is a partial View of FIG. 4 ilustrating a slightly
The weight of a ?oating roller and the pivoted arm to
different embodiment of means vfor varying the rate of
which it is attached becomes an important factor in main
response of the brake means incorporated in the ten
taining constant web tension when the pivoted arm moves
beyond its vertical axis running through its pivot point.
Thus, in application Serial No. 624,790 entitled, “Web
Tensioning Device,” ?led November 28, 1956, by A. L.
35
sioning device.
Referring initially to FIG. 1, supply rolls 1, 2 and
3 supply a web 4 to a web handling machine, normally
a printing press, not shown. As illustrated in FIG. 1,
Peterson, there is disclosed a spring for overcoming the
web 4 is initially run off supply roll 1, while supply rolls
weight of the ?oating roller and the arm to which it is
mounted when the arm swings beyond its vertical axis. 40 2 and 3 are reserve rolls which may swing in to paste
onto web 4 when roll 1 is exhausted. A tension belt 5
This application further discloses an electrical relay sys
passes over a portion of supply roll 1 so that when ten
tem incorporated in the brake control of the press Which
sion of the belt is increased by movement of the piston
will apply braking force to the rotating supply roll be
6 in tension cylinder 7, a braking force will be imparted
fore the brakes of the press are actuated in order to
compensate for the inertia of the rotating supply roll dur 45 to the rotating roll. Tension cylinder 7 is in turn con
ing an emergency stop of the press.
We propose in our present invention to eliminate the
separate spring shown in the previously mentioned appli
cation which compensates for the weight ‘of the roller
nected by conduit 8 to a control valve denoted generally
by the numeral 9 in FIG. 3.
A ?oating roller 10 mounted on a pivoted arm 11 is
placed between the rotating supply roll and the web han
and arm by utilizing a balance spring included in a pneu 50 dling machine and serves to provide a measure of con
stant tension in the running web. The arm 11, as shown
matic control valve. We further propose to provide for
in FIG. 3, is urged in a counterclockwise direction by
an easily adjustable rate means for varying the speed of
response, amount and duration of reaction means used
to return the ?oating roller to an original position so
means of a reference force air motor 12 which is con
nected by means of a conduit 13 to manual pressure con—
that substantially constant tension may be maintained
trol valve 14. Arm 11 is urged in a clockwise direction
by the tension existing in the running web 4. A conven
on a web even during emergency stop of a web handling
machine without the necessity of incorporating a phased
tional damper 15 serves to slow the movement of the
arm 11 about the pivot point 16 and to reduce hunting
electrical relay system between the brakes of the ma
chine and the supply roll.
‘of the arm. The control valve 9, air motor 12, damper
Broadly, We propose to use a variable pneumatic pres
sure control valve which has therein a pressurized re
60 15, and the linkage connecting these parts with the arm
11 are all incased within a housing 80.
Control valve 9 is actuated by movement of the ?oating
action chamber having a ?exible diaphragm at one end
roller 10 and arm 11 through link 20 and arm 21. Arm
for overcoming the force necessary to depress a spring
21 is pivoted about the point 22 so that when the ?oating
biased inlet valve contained in the control valve which
allows pressurized air to be admitted to a tension cylin 65 roller and arm 11 move in a counterclockwise direction,
arm 21 will rotate about point 22 to depress a piston 30
der and which returns the control valve to a balanced
which is slidable in housing 31 of the control valve 9.
state. The tension cylinder in turn exerts pressure on a
Roller 32 is mounted on the end of arm 21 in order to re
tension belt which passes over the rotating supply roll.
A ?oating roller mounted on a pivoted arm is positioned
duce friction of contact between the arm and the piston.
between the machine and the rotating supply roll so
‘Adjustable stops 33 and 33' limit movement of the arm
that the running web will pass ‘over its surface. The
21 while adjustable stops 34 and 34' limit movement of
pivoted arm is urged in one direction by means of a
arm 11 by hearing on portion 35 and 3-5’ thereof.
3,039,714
£3.
Control valve 9 has a ?exible diaphragm 40 having
therein an aperture through which a tube 41 is ?xedly
attached. Piston 30 is biased outwardly of the housing by
means of control spring 42 and is movable with respect
to tube 41. Spring 42 is of such strength as to balance;
the effect of gravity on ?oating roller 1%) and arm 11
when the arm swings beyond its vertical axis. Piston '30,
housing 31, ?exible diaphragm 40 and tube 41 all co
to the left. Under static or slow changing conditions, this
moment is balanced by the compression of spring 42 when
?exible diaphragm 40 is in a neutral or nearly neutral
position, as shown in FIG. 4, and when control valve 9
is in a balanced position neither delivering to nor exhaust
ing appreciable amounts of air from cylinder 7.
However, when the change in tension is appreciable
and such that the ?exible diaphragm is moved rapidly to
the right as shown in FIG. 4, the spring 42 must be com
operate to form an exhaust chamber 43 which is con
nected to a conduit not shown, which in turn leads to 10 pressed to a shorter length in order to generate a force
su?icient to balance the moment due to the weight of the
atmospheric pressure.
arm 11 and roller 10 in their new position. This is ac
The side of the diaphragm opposite spring 42 forms
complished by having pressure build-up in the reaction
with housing 31 and tube 41 a reaction chamber 44 which
chamber 44 to eventually equal that in the tension cylin
has therein a spring 45 biasing said diaphragm to the left
as shown in FIG. 4 against the force of spring 42. Re 15 der ‘6 or, as shown in alternate embodiment, the pressur
ized chamber 62, which will cause diaphragm 46 to re
action chamber 44 is ‘connected by means of conduit 4-3
turn to its original position and so compress spring 42.
to tension cylinder 7 as shown in FIG. 1 so that pressure
Any delay in pressure build-up in conduits 46 or 60
buildup in the chamber is dependent on pressure in the
Will in turn cause a delay in pressure build-up in the reac
tension cylinder. A rate valve 47 in conduit 46 varies
the rate of pressure build-up in the reaction chamber.
20 tion chamber and a consequent delay in the spring 42
being able to produce a balancing force. This delay in
Tube 41 terminates at one end in an exhaust valve seat
producing a balancing force will result in the roller con
50 which is adapted to be sealed by valve face 51 of slid
tinuing its movement to the left under the force of the
able poppet 52. Poppet 52 has on the end opposite that
air motor and increasing moment. The result is that the
of face 51 a valve face 53 which cooperates with seat 54
to form an inlet valve. Poppet 52 is ‘biased to the left as 25 diaphragm will move even further to the right and so
allow even more pressure build-up in the tension cylinder.
shown in FIG. 4 by means of spring 55. The space be
tween valve faces '51 and 53‘ comprises a pressure cham
ber 56 which is connected by means of conduit 8 with
tension cylinder 7. Inlet valve 53 opens into conduit 57
This motion of the ?oating roller might be considered
as a “self energizing action” which tends to increase the
amount of air flow to the tension cylinder and thus speed
Further, the “falling over” of
the ?oating roller tends to take up web loop rapidly as
tension of the web decreases.
It can be ‘cited that the reverse of the above operation
which is connected to a source of pressure, not shown. 30 up the corrective action.
The pressure chamber 56 is sealed ‘from the exhaust cham
her by means of 0 ring '58 carried in the lower half of
housing 31 and through which tube 41 may slide when
can occur if there is an increase in tension. The self
moved by diaphragm 49.
A slightly modi?ed form of the invention is shown in 35 energizing action can occur but in the opposite sense.
In other words, the ?oating roller becomes lighter and
FIG. 5 Where a conduit 60 connecting pressure chamber
the corrective action is sped up from the tension cylinder.
56 with reaction chamber 44. Conduit 60 has therein an
When tension in the web has been increased by applica
adjustable rate valve 61 to vary the rate of pressure build
tion of braking force on the rotating supply roll and after
up in the reaction chamber until it equals the pressure in
the pressure chamber. It is to be understood that the 40 the pressure in the reaction chamber is equal to that in the
tension cylinder or chamber 62, the arm 11 and roller
size of the pressure chamber 62 varies with the length of
will move to the right. Spring 45 and pressure in reaction
conduit 60 and with the desired rate of pressure build-up
chamber 44 will then move diaphragm 40 to the left back
in the reaction chamber. When this form of the inven
to the neutral position. Any further movement of the
tion is used, conduit 69 is, in effect, substituted for conduit
46.
45 diaphragm to the left, will open the exhaust port so allow
The operation of the device to maintain substantially
ing pressure to exahust from tension cylinder 7 to decrease
constant tension in the web throughout all phases of press
tension in the web.
operation is readily apparent by referring to FIGS. 1, 3
If the web handling machine speeds up momentarily,
the tension of the web will increase so causing arm 11 to
and 4. A desired pressure to give a desired tension in the
web is initially set in the system by means of manual 50 rotate in a clockwise direction. This will in turn allow
piston 30 to move outwardly of the control valve and to
pressure control 14. This in turn will impart pressure in
let the ?exible diaphragm 40 and tube 41 move to the
reference loading air motor 12 which will move arm 11
left under the in?uence of pressure in the reaction cham
in a counterclockwise direction to put tension into web 4.
ber 44 and spring 45 with the result that the exhaust valve
Arm 11 will move to the left under the in?uence of
pressure in the air motor. This in turn will move link 20 55 will open while the inlet valve remains closed. Pressure
in the tension cylinder and thus braking of the supply
and arm 21 so at to depress piston 30 in the control valve.
Depression of piston 30 will in turn exert a force on con
rolls will, therefore, decrease to compensate for the in
crease of tension in the web due to the increase in ma
trol spring 42 causing ?exible diaphragm 40 and 41 to
move in a right hand direction from a neutral position as
chine speed.
If there is an emergency stop of the machine so that
shown in FIG. 4. This movement of tube 41 will bring 60
the tension in web 4 drops sharply, it is obvious that
exhaust seat 59 into contact with exhaust face 51 of the
?oating roller 10 will move quickly to the left in order
poppet’ 52 to close the exhaust port. Further movement
of the tube 41 will depress poppet 52 against spring 55 to
open the inlet port and so allow admission of pneumatic
to compensate for the sharp decrease in tension. This in
turn will move piston 30 violently against spring 42 and
pressure from conduit 57 into the chamber 56. Increase 65 ?exible diaphragm 40 and so cause the tube 41 to open
the inlet port at valve 53 to allow a large amount of
of pressure in pressure chamber 56 will in turn be trans
pressure build-up in the tension cylinders. There will be
mitted to the tension cylinder 7 through conduit 8 to
a momentary period of time before pressure in the re
cause piston 6 to move to the left to increase the tension
action chamber 44 will build up to equal the pressure
in tension belt 5 and so exert a braking force on the ro
tating supply roll 1. As a result the rotating supply roll 70 exerted in the tension cylinder,.as shown in FIG. 4, or
will slow down and so tend to increase the tension in the
the pressure chamber, as shown in FIG. 3, due to the
pressure drop across either rate control valves 47 or 61.
moving web which will cause arm 11 and ?oating roller
During the period while pressure in the reaction chamber
10 to move back in a clockwise direction.
' The weight of ?oating roller 1t) and arm 11 have an in
is building up, maximum pressure will be exerted on the
creasing moment about the pivot point 16 as they move
tension cylinder while at the same time the ?oating roller
3,039,714
5
6
will be seeking its maximum pressure or tension position.
ated braking means operable by actuation of said variable
control valve for exerting braking force on said rotating
The net result of incorporating a rate control means
in the control valve is that pressure build-up in the ten
sion cylinders may be accelerated with relation to receipt
of a stop signal by the web handling machine. This fea
ture is shown in FIG. 2 which is a graph illustrating rate
of pressure build-up in tension cylinders with respect to
receipt of a stop signal by a press.
It is seen from an
inspection of FIG. 2, that ‘pressure builds up in the tension
cylinder faster when rate control means are provided.
We have found that by incorporating a tension control
device such as disclosed, that substantially constant ten-‘
supply roll, and rate control means for varying the rate
of pressure build up in said reaction chamber when said
variable pressure control valve is actuated by movement
of said arm to increase pressure in said pressure chamber;
pressure build up in said reaction chamber causing said
diaphgram to move against said control spring to return
said variable pressure control valve to a neutral position.
3. A web tensioning device according to claim 2 wherein
said reaction chamber connects by a conduit to said pres
sure chamber and said rate control means are interposed
in said conduit.
4. A web tensioning device according to claim 2 wherein
ditions of web handling machine operating speeds. The
rate control means disclosed provides a practical and 15 said braking means comprises a pneumatic tension cyl
e?icient means of varying the rate of braking force to be
inder in communication with said pressure chamber
applied to a rotating supply roll with the movement of
whereby admission of pressure in said pressure chamber
a ?oating roller while at the same time compensating
increases pneumatic pressure in said cylinder to increase
braking ‘force on said rotating supply roll.
for the inertia of the heavy rotating supply roll.
5. A web tensioning device according to claim 4 wherein
Having described our invention, reference should now 20
be had to the claims which follow for determining the
said reaction chamber connects by a conduit to said ten
sion cylinder and said rate control means are interposed
scope thereof.
in said conduit.
We claim:
1. A web tensioning device for controlling tension of
6. In a web tensioning device for controlling tension
a web running from a rotating supply roll to a web han‘ 25 of a web running from a rotating supply roll to a press
sion may be maintained on a moving web under all con
dling machine under all running speeds, comprising a
vertically extending ?oating roller pivoted for rotation
about its lower end contacting said web to measure and
maintain substantially constant tension in said movable
Web, a variable pressure control valve connected to a
by means of a ?oating roller mounted on a vertically ex
tending arm movable about a fulcrum located on the
lower end of said arm wherein movement of said arm in
response to change of tension in said web varies braking
force applied to said rotating supply roll; the improvement
comprising a variable pressure control valve having therein
?oating roller, a pressure chamber in said control valve,
a pressure chamber, an exhaust chamber and a reaction
a reaction chamber in said control valve communicating
chamber, a piston movable in said exhaust chamber and
with said pressure chamber, a ?exible diaphragm compris
in response to movement of said arm, a ?rst spring urging
ing one side wall of said reaction chamber, a control 35 said piston outwardly of said exhaust chamber to balance
spring bearing on said diaphragm and positioned between
moments due to the weights of said arm and roller when
said diaphragm and said ?oating roller to compensate
out of vertical alignment, a ?exible diaphragm separating
for change of effective Weight of said ?oating roller due
said exhaust chamber and said reaction chamber and
to movement beyond the vertical axis, pressure operated
bearing on said ?rst spring, a second spring in said reac
braking means operable by actuation of said variable
tion chamber urging said diaphragm in a direction oppo
pressure control valve for exerting braking force on said
site to said ?rst spring, a movable poppet having thereon
rotating supply roll, and rate control means for varying
an exhaust face and an inlet face, an exhaust seat ?xedly
the rate of pressure build up in said reaction chamber
positioned with respect to said ?exible diaphragm adapted
when said variable pressure control valve is actuated by
to engage said exhaust face, an inlet seat ?xedly positioned
45
movement of said ?oating roller.
with respect to said housing and adapted to engage with
2. A web tensioning device controlling tension of a
said inlet face, a third spring biasing said poppet to seat
web running from a rotating supply roll to a press, com
said inlet face on said inlet seat, conduit means connecting
prising a ?oating roll contacting said web, a vertically
said pressure chamber with said reaction chamber, and
source of pressure and actuated by movement of said
extending arm pivoted for rotation about a fulcrum
rate control means interposed in said conduit means for
at its lower end and having said roller mounted on 50 varying the rate of pressure build up from said pressure
one end thereof, motor means urging said arm and roller
chamber to said reaction chamber.
in a direction about said fulcrum to increase tension in
said web, a variable pressure control valve connected to
References Cited in the ?le of this patent
a source of pressure and actuated by movement of said
UNITED STATES PATENTS
?oating roller and arm about said fulcrum, a pressure
2,137,954
Sanford et \al __________ __ Nov. 22, 1938
chamber in said control valve, a reaction chamber in said
control valve commuting with said pressure chamber, a
?exible diaphragm comprising one side of said reaction
chamber, a control spring bearing on said diaphragm and
positioned between said diaphragm and said arm to com 60
pensate for change of moments due to change of position
of said arm and roller about said fulcrum, pressure oper
2,272,815
2,743,881
Otto ________________ __ Feb. 10, 1942
McWhorter ____________ __ May 1, 1956
709,449
Germany ____________ __ Aug. 16, 1941
Germany _____________ __ July 21, 1952
FOREIGN PATENTS
756,492
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