Note: Descriptions are shown in the official language in which they were submitted.
~478~3
BACKGROUND OF T~IE INVENTION
The present invention generally relates to locking
mechanisms, and more particularly to a fail-safe locking
device for reel carrying systems.
Frequently, machines of various types receive or
operate on a workpiece. In such machines, it is normally
imperative that the wor~piece be securely maintained in a
desired position, both for purposes for safety as well as
efficient operation. One particular case in point involves
wire stranders which manufacture stranded cable from a plural-
ity of wires. Some illustrative stranders are described in
the following U. S. patents: Nos. 2,499,246; 2,958,994 and
3,026,062. In one type of wire strander, known as a tubular
strander, the bobbins are placed in cradles which are mounted
on bearings in a tubular rotatable frame or housing. During
operation, the frame rotates while the cradle and the bcbbins
... .. . .
or reels are stationary. The wires are paid-out or pulled
from the bobbins and are brou~ht along the frame through gùides
until they are wound on the core wire which is usually taken
from a bob~in mounted outside the frame and passed through
; the frame along a path that is parallel to the axis of the
- machine, but displaced from the center as are the other wires
paid-out from'the bobbins loaded on the cradles inside the
tubular frame. Such tubular stranders, as well as rigid
stranders and planetary stranders are shown and described
in the products catalog issued by Ceeco Machinery Manufacturing
Ltd. of Ontario~ Canada.
A reel supporting unit for a cable stranding machine
is described in U. S. Patent No. 2,958,178. In the afore-
mentioned patent, a pintle assembly is actuatable for axialmovements to engage or release a reel. A compression spring
is provided within the pintle assembly which acts to cause
'~
cb/ - 1 -
647~3~
disengagement between the pintles and the reel, air pressure
being supplied to overcome the forces of the spring when
engagement of the reel is desired. However, the unit under
discussion does not provide fail-safe locking means and failure
of the air pressure system releases the reel, this being a
major disadvantage and safety hazard, for reasons which will
now be discussed.
Since stranders are usually operating at high speeds,
and in view of the large rotatlng masses, a large amount of
kinetic energy comes into play. As suggested above, safety
hazards involved in operating such machines are considerable.
For this reason, safety devices have been developed which
normally do not allow the operator to start the machines if
any malfunction exists. ~owever, due to failures in the safety
systems, as well as due to the pressures of production, there
have been numerous instances of accidents which have caused
considerable injury to personnel and damage to property.
A major problem with prior art safety devices is
that they normally require an operator to perform a number
of steps which are time-consuming and, therefore, such systems
are inconvenient and reduce production. As a result of this,
c ses are known where operators have intentionally failed to
take the necessary or precautionary steps which ensure the
safety of operation of the machine. Accordingly, operators
cannot always be depended upon to carry out the loading
operation as prescribed for a safe running of the machine,
especially when such safety procedures reduce the output of
the machines, and, therefore, may limit the incentive compen-
sation of the operator. Instances are even known where
electrical and mechanical safety systems have been overridden
or intentionally bypassed by operators when such systems pre-
vented the operation of a seemingly sound machine.
cb/ - 2 -
64788
The safety problem is particularly severe in the
case of tubular stranders since the speeds and the energies
involved are very high. With respect to such tubular
stranders, for example, there are basically three possibilities
or types of accidents which can take place. In the first
case, the bobbins or reels are not locked properly into posi-
tion and are released during speration. This jams the reels
between the rotatable frame and the cradle causing the cradle
to rotate. The reels are eventually thrown out of the tubular
frame through the opening thereof. Depending upon the direction
of exit, the damage can vary. If the reel is ejected upwardly,
it can penetrate through the roof of the building causing
injury to persons or damage to property. On the other hand,
it ~an be ejected sideways, thus increasing the chances of
injuries to personnel as well as damage to adjacent machines
that can, in turn, trigger further accidents. If the bobbin
is ejected downwardly, it usually jams the tubular frame
against the floor and shatters the tube. Accidents of this
type are frequent and heavy damage to property and people
.
have been recorded.
A second type of accident involving tubular stranders
can be triggered by a bearing failuxe which causes the cradle
to-rotate together with the frame. The consequences of such
failure are usually the same since cradles and locking mechanisms
are currently designed for stationary conditions and cannot
withstand the forces generated when the cradle and the bobbin
are rotating at approximately the same speed as that of the
tubular frame. The consequence of this situation is a release
of the reel and a type of accident similar to that described
above. The third type of accident which is possible is that
wire gets tangled up around the cradle causing the cradle to
rotate and resulting in an accident as above described.
cb/
~64713~3
Accidents caused by accidental release of reels
have also been recorded in the operation of rigid stranders
and planetary stranders, but due to the lower operational
speeds, serious damage is less frequent. Furthermore, the ;~,
open construction of these machines gives the operator a
better opportunity to see if a dangerous situation is
developing.
Similar problems such as those discussed in conn-
ection with above stranders can take place in other types of
machinery, particularly where rotatable parts or devices are
intended to be temporarily and securely retained on a machine.
For example, on those rigid stranders where reels are mounted
on cantilivered shafts, operator dependent locking devices
are presently used for securing the reels on the shafts.
Accidents have been recorded where reel have separated from
the shafts on which they are mountecl as a result of operator
failure to properly secure the manual locking devices.
Frequently, when the parts are held, such as by pintles, the
positional instability of the pintles is at least partly caused
bX the high speeds of rotation and the centrifugal forces
which are generated thereby. Accordingly, suc~ pintles must
not deviate from their retaining pbsitions irrespective of
operator negligence and substantially independently of mechani-
cal or electrical failure. Although ball locking devices
have been used before, for example, on rewinding machines
manufactured by Ceeco Machinery Manufacturing Ltd., and
pneumatically operated spring pintle assemblies are used on
tubular stranders manufactured, for e~ample, by the Stolberger
Maschinenfabrik & Co. KG of Aachen, West Germany, there is
not presently known a fail-safe device for reel carrying systems.
In the following U. S. Patents, some further attempts
at providing fail-safe operation in reel suppor-ting machines
cb/ 4
~L~6~71~8
are described: Nos. 2,773,344; ~,787,884; 2,~60,479; 2,987
870; and 3,147,702. Generally, the devices disclosed are
complex in construction and do not provide the safety margin
contemplated by the present invention. For example, the reel
supporting devices disclosed in U. S. Patent Nos. 2,787,88~
and 2,860,479 utilize tie bolts which pass through the reel
being supporte~ as well as through the pintle members. The
tie bolts are either provided with head members or t~hreaded
ends for engagement with suitable retaining members which
serve to draw the pintle assemblies together into engagement
with the supply reel. While the tie bolts can prevent separ-
ation of the pintles and release of the reel under normal
circumstances, separation of the threaded tie bolt ends from
the mating or cooperating members could cause reel release.
In any event, the systems described require operator input
and, ~or this reason, suffer the same disadvantages described
above. In U. S. Patent No. 3,147,702, there is disclosed a
roll supporting arrangement for a printing press which uses
a fluidpressure cylinder biased to release the supported roll,
air pressure being used to maintain engagement with the roll.
An externally mounted latch is provided to prevent accidental
release in the event of air pressure loss. The last mentione~
device does not relate to stranding machines and a pivotally
mounted latch would not normally be suitable with heavy
machinery such as stranding machines. Additionally, the latch
of the patent does not act directly on the printing press roll
engaging member and thisfurther reduces the reliability of the
device to avoid failure. Finally, the device being described
requires manual release of the latch to move the cylinder, and
the fluid pressure system which actuates the press roll support-
ing member does not cooperate with the latch. For the afore-
mentioned reasons, the prior art reel supporting systems do
cb/ - 5 -
~64715 ~3
not provide the margin of safety, the ease and simplicity
of operation, and the minimal amount of operator input which
are characteristic of the present invention.
SU~ARY OF THE INVENTION
. .
. Broadly speaking, the problems of the prior art are
overcome by the present invention which provides a fail-safe
locking device for reel-carrying systems, comprising an
actuatable member mounted on a support member for slidable
movement relative thereto along an axis; reel engaging means
mounted on the actuatable member for sharing the axial move-
ments thereof between reel engaging and disengaging positions;
biasing means for urging the actuatable member to one of the
positions; locking means cooperating with the support member
and movable between locking and releasing positions for permitt-
ng movement of the actuatable member from the one to another
of the positions only in the releasing position of the locking
.,..... means; and fluid pressure means forrnoving the locking means
to the releasing position only upon application of fluid
medium under pressure with attendant movemen~ of the actuatable
member to the other of the positions, the locking means being
arranged to directly cooperate and block the movement of the
actua`table member to the other of the positions in the locking
position of the locking means to thereby provide fail-safe
operation during reel engagement independently of the fluid
medium pressure provided by the fluid pressure means.
BRIEF DESCRIPTION OF TXE DRAWINGS
Further advantages of the invention will become
apparent from a reading of the following specification describ-
ing illustrative embodiments of the invention. The specification
is to be taken with the accompanying drawings, in which:
Figure 1 is a perspective view of a cradle of the
type receivable within a tubular strander, showing a pintle
cb/ - 6 -
7138
assembly according to the present invention mounted on the
cradle, and showing a reel being lowered into the cradle while
the pintles are in retracted positions;
Figure 2 is an enlarged top plan view of the cradle
shown in Figure 1, as viewed along line 2-2 in Figure 1, and
showing in dashed outline the manner in which the cradle is
pos,itioned within the tube of a tubular strander, and the
manner in which the reel is supported within the cradle;
Figure 3, appearing Gn the ,same sheet as Figure 1,
is a s,ide elevational view of the cradle shown in Figure 2,
as viewed along line 3-3;
Figure 4 is an enlarged cross-sectional view of
one of the pintle assemblies taken along lines 4-4 in Figure
2;
Figure 5 is an enlarged view of the pintle assembly
shown in Figure 4, sho~ing the details of the locking mechanism;
' ' Figure 6, appearing on the same sheet as Figure 1,
is a sectional view of the pintle assembly ta~en along line
6-~ in Fi~ure 4;
Figure 7 is similar to Figure 4, but showing the
- pintle assembly having moved from an extended position to a
retracted position upon application of pneumatic pressure;
Figure 8 is a longitudinal cross-sectional view of
the upper half only of a pintle assembly in accordance with
another embodiment of the present invention, showing the
same in an extended or retaining position.
Figure 9.is similar to Figure 8, but showing the
pintle assembly having moved from the extended position to
a retracted position upon application of an externally applied
pneumatic pressure.
Figure 10 is a fragmented top plan view of a rigid-
type strander showing how the locking device of the present
cb/
1~ 478~3
invention can be used in shaft mounted reel-carrying systems;
Figure 11 is an enlarged cross-sectional view of
the strander and bobbin or reel shown in Figure 10, taken
along line 11-11 to show the details of the reel engaging
means in the form of moving fingers in place of the pintles
shown in the earlier embodiments;
Figures 12 and 13 are similar views to Figure 11,
but showing another embodiment of the reel-engaging means
in the reel locking and releasing positions respectively;
-Figures 1~ and 15 are similar views to Figures 12
and 13 respectively but showing still another embodiment of
the reel-engaging means;
Figure 16 is similar to Figure 2, but showing in
dashed outline portions of the fluid pressure system, includ-
ing the fluid pressure cylinders, which cooperate with further
embodiments of the present invention which are illustrated
.. ln Figures 17-24;
Figure 17 is an enlarged c:ross-sectional view,
partially broken away, taken along ].ine 17-17 in Figure 16,.
and showing a further embodiment of the present invention.
Fi~ure 18 is a cross-sectional view taken at line
: . 18-18 in Figure 17, and showing the arrangement of parts of
the embodiment shown in Figure 17 in the disengaged position
of the pintle assembly from the reel being carried;
Figure 18a is an enlarged view of a portion of the
slot shown in Figure 18 with the pin positioned at the proximate
end of the slot corresponding to the reel-engaging position
of the pintle assembly.
Figure 19 is similar to Figure 18, but showlng the
arrangement of parts in the reel-engaging position of the pintle
assembly;
Figure 20, appearing on the same sheet as Figure 17,
cb/ - 8 -
~6~7~8
is a cross-sectional view taken along line 20-20 in Figure 18;
Figure 21 is generally simil.ar to Figures 18 and 19,
but showing a yet further embodiment of the present invention;
Figure 22 is a cross-sectional view taken along line
22-22 in Figure 21;
Figure ~3 is a fragmented cross-sectional view taken
along line 23-23 in Figure 21; and
Figure 24 is a cross-sectional view taken along
line 24-24 in Figure 21.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The present invention will be primarily described,
by way of illustration only, with respect to pintle assemblies
on tubular-type stranders. However, as will become evident
to those skilled in the art, and as will be briafly described :~
in connection with Figures 10-15, the locking device of the
present invention can also be used with other reel-engaging
. means on other reel-carrying systems.
Referring now $pecifically to the drawings, in which
the identical or similar parts have been designated by the
same reference numerals throughout, and first referring to
Figures 1-3, the locking device of the present invention is
generally designated by the reference numeral 10. As will
become evident from the description that follows, and as noted
above, while the fail-safe locking systems of the present
invention are described as being incorporated in pintle assem-
blies mounted on cradles and the like as used on wire stranding
mach.ines, the same or similar fail-safe locking systems can
be used in many other types of applications where a movable
or retaining member is intended to normally be positioned
in an extended or retracted position and only moved to a
retracted or extended position respectively when the associated
machine is not in operation.
cb/ - g -
~L~647~38
As can best be seen in Figures 2 and 3, two pintle
assemblies 10 are provided, although it should be clear that
in certain instances only a single locking device or pintle
- assembly 10 in accordance with the present invention may be
sufficient, in which case the other pintle is fixedl~ mounted
on the frame. The pintle assemblies 10 are shown to be provided,
at the free ends facing inwardly or facing each other, with
pintles 12. The pintle assemblies 10 are mounted on a cradle
frame 14. The cradle 14 is typically of the type used in high
speed tubular stranders manufactured by Ceeco Machinery Manu-
facturing Ltd. The tube 16 of such tubular stranders are
shown in dashed outline in Figures 2 and 3. Such cradles 14
are typically provided with a ~uick release brake mechanism
1~ which cooperates with a brake ring 20 in a known or con-
ventional manner. A drive dog 22, also of a conventional
type, is provided on the brake ring 20. A conventional reel
stop 24 is shown which is adapted to cooperate with the reel
26 when the same is received within the cradle 14 and supported
by the pintles 12.
2Q In Figure 1, the reel 26 is shown to be filled with
wire 28 which is to be stranded, which reel includes a bore 30
dimensioned to receive the pintles 12 therein. The reel 26 is
shown being lowered by a hoist 32 into position within the
cradle 14. As will be described hereafter, the pintles 12
are, during such an operation, in the retracted positions
thereof to permit the reel 26 to be lowered into the cradle
14, after which the pintles 12 are moved to their extended
positions, as suggested in Figures 2 and 3 in which condition
the reel 26 is securely retained. The pintle assemblies 10
of the present invention assure that the pintles 12 remain
in their extended positions during the operation of the machine
to retain the reels 26 securel~ and prevent the same from
cb/ - 10 ~
~647~
inadvertently or accidentally being ejected from the cradle 14.
Referring to Figure 4, thereis shown the details of
the pintle assembly 10 in accordance with one presently pre-
ferred embodiment of the present invention which forms the
fail-safe locking system which assures that the pintles 12
are locked in the extended positions thereof, this taking
place automatically without the need for the operator to take
precautionary steps as has heretofore been required. Addi-
tionally, the pintle assembly 10 of the present invention
permits and causes retraction of the pintles 12 only upon
application of a fluid under pressure, such as pneumatic or
hydraulic pressure, as will be described hereafter.
The cradle 14 includes a frame which may, for example,
include an inwardly directed annular frame 34 to which a cylin-
der 36 and an end plate 38 are securely attached by means of
bolts 40. The end plate 38 includes an inwardly directed
cylindrical wall portion 42 which defines an axial bore or
cylindrical cavity and which is provided with ~ne or more
through openings 44, as is best shown in Figure 5 and will be
more ~ully described hereafter.
As can best b~ seen from Figure 4, the cylinder 36
includes a stepped-down cylindrical wall 37 which defines a
cylindrical cavity or bore 37' which receives a portion of a
first actuatable member or primary locking element 46 which
is mounted for slidable movement within the cylinder 36 relative
to the support member or cradle 14 along an axis. The primary
locking element 46 is in the nature of a shaft member and
includes a shaft portion 4~ dimensioned to correspond with
the interior bore or cavity defined by the cylinder 36. The
primary locking element 46 is provided at one end thereof with
a piston portion S0 which will be more fully described hereafter.
The primary locking element 46 is provided at the
cb/ - '1 ~
788
end opposite to where the piston portion 50 is provided with
a front plate 52 which is secured to the shaft portion 48 by
means of bolts 54. The front plate 52 secures ball bearings
56 against a spring support plate 58 which in turn is urged
in the direction of the spxing support plate by means of a
helical compression spring 60 which acts between the cradle
frame 14 and the spring support plate 58.
Mounted on the ball bearings 56 is the pintle 12
which is clamped to the ball bearings by means of a back-up
ring 62 which is connected to the pintle 12 by means of bolts
64 and spring lock washers 66 as shownO In order to protect
the spring 60 and keep the interior of the pintle assembly 10
free of contaminants, there is advantageously provided a
spring cover 68 which is connected to the back-up ring 62
and which shares the common axial movement of the pintle 12
together with the movements of the primary locking element 46.
With this arrangement, the primary locking element
46, to~ether with the pintle 12, is urged outwardly to the
extended position thereof as shown in Figure 4 to cause at
least a portion-of the pintle 12 to be received within the
bore 30 of the reel 26.
To limit excessive movements of the primary locking
element, the set screw 72 is positioned ~ithin a groove 70
to prevent rotation of the primary locking element 46 when
the pintle 12 and the reel 26 rotate. Locking of the primary
locking element against rotation prevents wear, for example,
of the O-ring 82 and prolongs the life of the locking device
10. The primary locking element 46 is limited in its move-
ment beyond its extended position by virtue of its piston
portion 50 coming into engagement with an annular shoulder of
the cylinder 36 as shown in Figure 4.
The cylinder 36 as well as the end plate 38 are
cb/ - 12 -
~Ç;47~8
configurated and cooperate together to form a bore or cavity
74 which generally contains the piston portion 50, and which
is defined by a cylindrical surface 76 which corresponds to
the peripheral configuration of a bearing surface 78 formed
on the piston portion 50.
As will be more fully described hereafter, there is
provided a conduit 80 which is in communication with the bore
or cavity 74 for selectively applying a fluid medium under
pressure against the bearing surface 78. To ensure efficient
operation, there is advantageously provided a seal about the
periphery of the piston portion 50, shown in Figure 4 as being
an O-ring 82.
The primary locking element is provided with an abut
ment surface 84, shown in the embodiment of Figure 4 as being
generally in the region of the piston portion 50. The abut-
ment surface 84 is an important feature of the present inven-
tion and will be more fully described below. The primary
locking element 46 is also provided with a bore or cavity 86
which.is defined by a cylindrical su:rface 88, which bore or
~0 cavity 86 is also in fluid fIow communication with the conduit
-80. In this manner, application of a fluid medium under
pressure into the conduit 80 simultaneously applies the fluid
under pressure to both cavities 74 and 86.
Coaxially arranged with the primary locking element
46 is a second actuatable member in the nature of a secondary
mechanical locking element or safety plunger 90 which has a
shaft portion 92 provided with a piston portion 94 at one end
thereof which is similar in configuration and functions as does
the piston portion 50 of the primary locking element 46. The
piston portion 94 has a bearing surface 96 which faces the
interior of the bore or cavity 86, and has a periphery which
generally corresponds to the shape of the cylindrical surface 88.
- 13 -
cb/
47~
In order to prevent escape of the fluid under pressure and
generally improve the operation of the device, there is
advantageously provided a seal extending about the periphery
of the piston plunger 94, such as in an annular groove 98
(shown in Figure 5), which may be in the nature of an O~ring
100 .
The end of the shaft portion 92 opposite to where
the piston portion 94 is provided is formed with an axial bore
102 as shown which receives a helical compression spring
104 which acts between the safety plunger 90 and an end pIate
106 fixedly mounted relative to the cradle frame 14 to thereby
urge the safety plunger or secondary mechanical loc]cing plunger
90 in the direction of the primary locking~element 46 to move
the piston portion 94 inwardly of the bore or cavity 86.
Referring particularly to Figure 5, the safety plunger
or locking element 90 is formed with a step or notch 108 in
its exterior surface to define a generally bevel or inclined
surface 110 as shown. An important :Eeature of the present
invention is that when the safety plunger 90 is in its disabling
position shown in Figures 4 and 5, the greater dimension of
the sha~t portion 92 is substantially in opposition to the
through opening 44 in the wall portion 42. Therefore, the
function o~ the spring 104 is to urge the safety plunger 90
to move to the disabling position and bring the greater dia-
meter or dimension on the shaft portion of the safety plunger
substantially in opposition to or in registry with the through
opening 44, for reasons which will be described below.
To prevent excessive axial movement of the safety
plunger 90 beyond its disabling position shown in Figures 4
and 5 as a result of the action of the spring 104, suitable
stop means may be provided. As best shown in Figure 6, one
form of stop means which may be used for this purpose may
cb/ - 14 -
~ 647~38
consist of one or two pins 112 which are spaced from the axis
and directed substantially normally thereto. Such pins 112
are mounted on the wall portion 42 at a radial distance to
substantially correspond to the radial distance of the bevel
or inclined surface 110 from the axis, so that the pins 112
abut against the bevel or inclined surface 110 to thereby
limit in this manner excessive axial movements of the safety
plunger 90. However, any other type of stop means may be
used in place of the pins 112.
1~ Referring to Figures 4 and 5, an important feature
of the present invention is the provision of a blocking member
in the nature of a hardened steel ball or sphere 114 which is
captured within the through opening 44 and mounted for only
radial movements. In Figures 4 and 5, the ball 114 is shown
to be in a radially outward locking position wherein the ball
114 is at least partially positioned in the path of movement
... .
of the abutment surface 84 to block movement of the primary
l.ocki~g element 46 from the extended position as shown in
Figure 4. In this condition, the ball 114 is maintained in
~he radially outward or blocking position due to the disabling
position of the safety plunger 90 which forces the ball 114
to the position shown as the result of the action of the
spring 104.
The diameter of the ball 114 is selected to be
greater than the thickness 116 of the wall portion 4?, so
that at least a portion of the ball 114 proiects beyond
the wall portion 42 to assure that the primary locking element
46 is biocked and prevented from axially moving from its
extended position. With this arrangement, it should be clear
that the ball 114 is captured within the through opening 44
and prevented from moving axially as the result of the fixed
nature of the wall portion 42. However, the ball 114 may
cb/ - 15 -
`" 1~64~
move radially inwardly or outwardly, and will so move in
response to radial forces applied thereto. However, although
the ~rimary locking element 46 may apply radially inward forces
to the ball 14, the ball cannot move out of the blocking path
or path of movement of the abutment surface 84 so long as the
safety plunger 90 is in its disabling position as shown in
Figures 4 and 5.
Referring to Figure 5, the increased diameter shaft
portion 92, which has a substantially cylindrical external
surface, is provided with a longitudinal surface groove 118
for each hardened steel ball 114. The grooves 118 terminate
short of the step 108 to form ledges or banks 118' which pre-
vent a ball 114 fro~ rolling out of the groove 118 into step
108, wherein the primary element 46 applies a radially inward
force on the ball, such as when centrifugal forces act on the
primary element 46.
As is evidenced from Figures 4 and 5, the primary
locking element 46 cannot move because the four balls 114 do
not allow it to retract into the cylinder 36 as long as the
secondary safety plunger 90 is in the extended locked position.
However, if pressure is applied-to the pintle, this force will
act on the four balls pushing them radially inwardly toward
the safety plunger 90. Centrifugal forces will tend to urge
the primary locking element 46 to apply such inward forces
on the balls 114, as well as tend to move the secondary safety
plunger 90 to its retracted, enabling position against the
action of the spring 104. The spring 104 can be designed in
such a way as to maintain the safety plunger in its disabling
position under the effect of high centrifugal forces, but, even
if it is such that it could no-t maintain the safety plunger in
its disabling position under high centrifugal forces, the
ledges or banks 118' prevent the safet~ plunger from moving
cb/ - 16 -
~164713~3
from its normally extended disabling position to its retract-
ed enabling position whenever the primary locking element 46
applies radially inward forces on the safety plunger. This
is due to the engagement between the balls 114 and the ledges
118'. Therefore,.even under very high pressure, the pintle
12 is mechanically and positively locked in positionO Even
if the cradle 14 rotates at the speed of the tubular frame,
and considerable axial forces are applied to the pintle, it
would be impossible to obtain a release up to forces that will
destruct the entire assembly. During normal operation, the
primary locking element does not apply radially inward forces
on the balls 114 and movement of the safety plunger 90 against
the action of the spring 104 merely causes the balls 114 to roll
over the ledges or banks 118' and subsequently drop into the
step 108 as described above. By making the ledges or banks 118'
typically a few thousandths of an inch high, these are small
-. enough to permit the balls to roll over them without any diffi-
culty under retracting movements of the safety plunger 90,
while actually locking the safety plunger whenever the primary
locking element 46 appliad radially inward forces on the ~alls
114. As noted above, even small ledges or banks have been
. found to be s.atisfactory to prevent inadvertent unlocking of
the pintle assembly 10 even under the highest anticipated
centrifugal forces.
While one blocking member may be provided, it is
advantageous to provide a plurality of such blocking members
which are substantially uniformly spaced from each other about
the axis of the pintle assembly 10 and, in the embodiment shown
in Figures 1-6, there are four balls 11~ spaced from each other
~0 apart, as best shown in Figure 6. Each ball 114 is received
with an associated through opening 44, and the operation of
each of the balls 114 is substantially the same as described
cb/ - 17 -
~1~647~38
above. Also, while a spherical ball bearing is shown in the
presently preferred embodiment, it will become evident to one
skilled in the art that the blocking members need not be spheri-
cal, but may assume any desired configuration, as long as the
blocking members at least partially project into the path of
movement of the abutment surface 84 when the safety plunger
90 is in its disabling position. Thus, tne blocking members
may be in the nature of cylinders, pins, plungers and the like
Other types of locking arrangements may also be used as will
be described in connection with Figures 16-24. The present
inyention, there~ore, is not limited to the specific Gonstructions
described, but to the general principles which have been des-
cribed which provide automatic and positive locking of the
primary locking element 46 by means of the actions of a lock-
ing element, such as a safety plunger 90 in cooperation with
the movable blocking element or ball 114 which cooperates with
an abutment surface of some type on the primary locking element.
The pintle assembly 10 is advantageously also pro-
yided.with an electrical limit switch 120 which serves as a
sens.or means for monitoring the position o~ the safety plunger
9Q. The limit switch 120 has a plunger 122 which projects int~
the path of movement of the safety plunger 90, the position
of the limit switch 120 being maintained by means of a limit
switch clamping plate 124 which is fixedly mounted on the end
plate 38 by means of bolts 126. To facilitate actuation of
the limit s~itch.120 and prevent damage thereto, the shaft
portion 92 of.the safety plunger 90 is aavantageously provided
with a bevel surface 128 which is in the nature of a cam surface
which initiates the actuation of the limit switch 120 when
the safety plunger 90 moves from the disabling position thereof
shown in Figures 4 and 5 to an enabling position to be described.
The limit swi.tch 120 is provided with electrical conductors
cb/ - 18 -
1~6471!3~3
or leads 130 which may be connected to any suitable electrical
circuit which may, for example, disconnect the machine on which
the pintle assembly 10 is mounted from the power mains or may
initiate an alarm upon movement of the safety plunger 90 from
its disabling position, which thereby enables the movement of
the primary locking element 46.
Referring to Figures 2 and 4, the conduit 80 is shown
to be in fluid flow communication with a nipple 132 which is in
turn coupled by means of an elbow 134 to a tubing 136 which
extends to an accessible portion of the cradle 14. The tubing
136 is connected by means of a female branch tee 138 to a speed
coupler and connector 140. As is evident from Figure 2, the
female branch tee 138 permits steel tubes to emanate from the
coupler 140 to both pintle assemblies 10 on opposing sides of
the cradle frame 14.
The operation of the pintle assembly 10 will now be
described to the extent to which it has not been described above~
The spring 60 urges the primary locking element 46 to its
extended position shown in Figure 4, and the safety plunger 90
is urged to its disabling.position as a result of the action o~
the sprin~ 104, causing the ball 114 to ride over the surfaces
llO.and ledges 118' ~nd on to that portion of the shaft portion.
~2 of greater diameter to cause at least a portion of the balls
114 to move into the path of movement of the abutment surfaces
84. This action of the helical compression springs 50 and 104
automatically moves the pintle 12 to its extended or retaining
position wlthout reliance upon the operator of the machine.
The primary locking element 46 and the safet~r plunger 90 will
remain in these extended and disabling positions respectively
until the operator of the machine applies a fluid medium under
pressure to the coupler 140.
In order to insert a reel 26 or remove the same
cb/ - 19-
1~69~138
from the pintle 14, the operator applies a mating coupler to
the connector 140, such as an air pressure hose, and simul-
taneously applies pressure through the tubings 136 to the con-
duits 80 of each of the pintle assemblies 10. Application of
air under pressure into the conduit 80 of the pintle assembly
10 shown in Figure 4 causes a pressure P to be developed on
each of the bearing surfaces 78 and 96. However, initially
t~ pressure applied to the bearing surface 78 does not move
the primary locking element 46 because it is locked by the
balls 114 which are in abutment against the surfaces 84 as
described above. However, the fluid pressure P is shown to
be acting upon the bearing surface 96 in Figure 4 to develop
a force Fl which acts upon the safety plunger 90 and urges
the same to move away from its disabling position and move
to its enabling position against the action of the spring 104.
Movement of the safety plunger 90 to its enabling position
shown in Figure 7 brings the step 108 into registry with the
through openings 44 to permit the balls 114 to move sufficiently
radially inwardLy so as to move out of the path of movement
of the abutment surfaces 84. Thus, movement of the safety
plunger 90 in this manner causes the ball bearings to move
from their locking to their releasing positions.
Referring to Figure 7, the fluid under pressure
continues to apply pressure P upon the bearing surface 78 to
thereby apply a force F2 which causes the now released primary
locking element 46 to move from its extended position to its
retracted position against the action of the compression spring
60~
The above-described construction, therefore, automati-
cally provides positive locking of the primary locking element46 which bears the pintle 12, while the same external fluid
under pressure which releases the primary locking element 46
cb/ - 20 -
~647B~3
also urges the same to move to its retracted position to
thereby facilitate insertion and removal of the reels 46
from the cradle frame 14.
As soon as the pneumatic or hydraulic pressure is
applied to the conduit 80, and the safety plunger 90 is moved
from its disabling to its enabling position, the limit switch
120 is actuated by virtue of engagement between the plunger 122
and the cam surface 128. This can be used, as suggested above,
to disable the machine by removing the electrical power there-
from whenever the safety plunger 90 is in any position other
than the disabling position shown in Figure 4, or may be used
to actuate an alarm which provides notice to the operator
that the pintle 12 is not in its extended or retaining position.
When used in conjunction with cradles 14 on tubular
stranding machines, the locking device including the ball 114
and the bearing surfaces 84 comes into play only when needed
since, during normal operation the spring 60 is sufficient to
maintain the pintle 12 in the reel 26. Only when a malfunction
occurs is the locking device which includes the abutment
sur~aces 84 and the balls 114 subjected to stresses. This
construction, therefore, increases the life and the reliability
of the device because under normal circumstances the abutment
or engaging surfaces which. make up the locking device are not
subjected to any wear at all.
In the embodiment 10 shown in Figures 1-7, the springs
60 and 104 are arranged to urge the primary locking element 46
and the safety plunger 90 in a common axial direction, the
bearing surfaces 78 and 96 facing that same axial direction.
In this manner, the application of a fluid medium under pre-
ssure causes the primary`locking element 46 and the safety
plunger 90 to be successively axially shifted or displaced
against the actions of the two springs respectively. ~eferring
cb/ - 21 -
1~64788
to Figures 8 and 9, a second embodiment 10' of the pintle
assembly is shown which need not rely on spring action alone
or spring actionin combination with ledges 118' to maintain the
; safety plunger 90 in its disabling position under the action
of centrifugal forces. Here springs 60 and 104' are arranged
to urge the primary locking element and the safety plunger
90' in opposing axial directions. This is done to benefit
from the effect of the centrifugal forces acting on the safety
plun~er to urge the same to its disabling position and thereby
add another measure of safety to the locking device 10'. The
bearing surface of each associated actuatable member faces
the direction of action by the cooperating spring thereon.
In Figure 8, the primary locking element 46' is shown in its
e~tended or retaining position due to the action of the com-
pression spring 60, this position being towards the left as
viewed in Figure 8, similar to the corresponding position of
,~ the pintle assembly 10 shown in Figure 4. ~owever, now the
spring 104' acts between an abutment or shoulder on the wall
portion 42' and the safety plunger 90' to move the same to
the disabling position which with the embodiment 10' i5 towards
the right as viewed in Figure 8, as compared with the corres-
ponding position towards the left with the embodiment 10 shown
in Fi~ure 4.
Upon application of a fluid medium under pressure
into the conduit 80', forces F3 and F4 are simultaneously applied
to the bearing surfaces 96' and 78' respectively. HoWever,
the primary locking element 46' cannot move in the direction of
force F4 because it is positively locked by virtue of the engage-
ment between the ball 114 and the abutment surface 84'. The
only element which is free to move is the safety plunger 90'
which moves towards the left, as viewed in Figure 7, in
response to the force F3.
cb/ - 22 -
L7~38
Referring to Figure 9, once the safety plunger 90'
has moved into the bore cavity 86 sufficiently so as -to bring
the step 108 or the inclined surface 110' sufficiently to the
left so as to permit the ball 114 to move out of the path of
movement of the primary locking element 46', the force F4
causes the primary locking element 46', together with the
pintle 12 mounted thereon, to move towards the right to the
position shown in Figure 9. The movements of the safety plunger
90' from the disabling to the enabling positions, the ball
114 from the locking to the releasing positions, and the move-
ment of the primary locking element 46 from the extended or
retaining positions ~o the retracted or releasing positions are
all automatically achieved upon application of a fluid medium
under pressure to the conduit 80'. As soon as such pressure
is removed, compression springs 60 and 104' automatically, and
without any assistance from the operator, revert to their
initial positions shown in Figure 8 to positively lock the
pintle 12 in the operative or retaining position.
In the embodiment 10' shown in Figures 8 and 9, the
safety plunger is maintained in the disabling position by the
action of the centrifugal forces acting thereon. The centrifugal
. forces in this embodiment urge the safety plunger in the same
direction as does the spring 104', as opposed to the embodiment
lQ where the centrifugal forces oppose the spring 10~ and tend
to move the safety plunger to the enabling position. ~lthough
this alternative embodiment shown in Figures 8 and 9 would,
therefore, seem to provide superior safety, testing has shown
that the pintle assembly 10 adequately and positively maintains
the safety plunger 90 in the disabling position shown in Figure
4 even at forces considerably greater than the ones that would
be encountered in the worst accidental condition as discussed
above. The pintle assembly 10 is somewhat preferred because
cb/ - 23 -
~C~64~8~
of its simplicity of construction. As can be seen, the pintle
assembly 10' uses a considerable number of additional O-rings
82', 142 and 144, and this increases the chances of malfunction
and maintenance.
To illustrate some other examples or possible appli-
cations of the fail-safe locking device in accordance with the
present invention, reference is made to Figures 10 and 11. Here,
a rigid--type strander 146 is shown to comprise a frame generally
in the nature of a hollow body 148. A support member in the
nature of a shaft 150 is shown fixedly or rigidly mounted on
the frame 148, the shaft 150 having an axis substantially normal
to the axis of rotation of the hollow body 148. Such an arrange-
ment may be utilized to pay off wire from the bobbin as a
result of centrifugal forces acting on the wire as the bob~in
or reel 15~ rotates about the axis of the hollow body 148.
The bobbin or reel 152 has a bore 152a dimensioned to receive
- ~ the shaft 150 as shown in Figure 11. The bobbin or reel 15?
has upper and lower flanges or circular members 152b, 152c
which define the annular space in which the wire on the bobbin
is wound.
In stranders of this type, wherein rotation of a
shaft or hollow bod~ has the tendency to eject the bobbins or
reels, it is imperative that suitable locking means be provided.
As best shown in Figure 11, the fail-safe locking device lOa is
shown incorporated within the shaft 150 and fixedly secured
thereto in any suitable or conventional manner. The shaft
portion 48a of the actuatable memberor primary locking element
46 is shown ko be provided with a conical or tapered outer
surface, tapering inwardly in the direction of the reel or
bobbin engaging means. ~ere, in place of a pintle 12 mounted
on the shaft portion, the reel or bobbin engaging means
includes a plurality of fingers 154 spaced from each other
cb/ - 24 -
~64~7B8
about the axis of the shaft 150 and moun-ted for slidable move-
ment in the radial direction on the shaft 150. Suitable com-
pression springs 156 are provided which urge the fingers 154
radially inwardly or into the confines of the shaft 150. The
springs 156 have the tendency of moving the fingers 154 to
their reel or bobbin disengaging position, which position the
fingers 154 move to when the shaft portion 48a is in the
retracted position as suggested by the dashed outline in Figure
11. As noted above, the primary locking element is normally
locked in the extended position thereof shown in Figure 11.
As should be evident, when the shaft portion 48a moves to
its locked, extended position shown in Figure 11, the fingers
154 ride on the tapered external surface of the shaft portion
as shown and thereby, are thrust outwardly to the locking or
engaging positions shown. The shaft portion 48a forces *he
fingers 154 radially outwardly against the actions of the
springs 1~6 to the engaging or locklng positions thereof, the
fingers engage the bobbin or reel 152 at the upper flange or
circular member 152b. Since the shaft 150 is rigidly or
fixedly connected to the rotating frame or hollow body 148,
the fingers 154 likewise maintain the bobbin or reel 152 on
the shaft 150 during rotation thereof. From the above-described
emhodiments, application of a pneumatic or hydraulic pressure
in the line 158 causes the shaft portion 48a to move to a
retracted, releasing position (as shown in dashed outline in
Figure 11) to thereby permit the fingers 154 to move radially
inwardly by the action of the springs 156 and the bobbin or
reel 152 may be released.
Referring to Figures 12 and 13, there is shown a still
further embodiment of reel engaging means which avoids the need
to maintain the springs 156' in a state of compression during
the locked condition of the bobbin, as is the case with the
cb/ - 25 -
~647~
embodiment shown in Figures 10 and 11. In Fiyures 12 and 13,
the shaft portion 48b is normally locked in the retracted
position, as opposed to the extended position as shown in
Figure 11~ With the shaft portion 48b normally being in the
retracted position as shown in Figure 12, the shaft portion
48b may be provided with a tapered or conical surface which
tapers in an opposite direction as the taper of the shaft por-
- tion 48a. With the embodiment shown in Figures 12 and 13,
the locking device lOb must beslightly modified, as should be
evident to those skilled in the art, to cause the shaft por-
tion 48b to be in the locked position of the shaft portion
when it is in a retracted position, shown in Figure 12. Here,
the fingers 160 have a generally sloping surface as shown
riding upon the conical or inclined surface of the shaft por-
tion 48b. When the shaft portion 48b is in the retracted
position, the compression springs 156' urge the fingers 160
to move to their extended or locked positions. It will,
therefore, be evident that with the shaft portion ~8b locked
in the retracted position and by utilizing the tapered surface
of the shaft portion 48b, the fingers 160 may be maintained
in their extended locking positions without placing the
springs 156' in a state of compression.
When the shaft portion 48b is moved to its extended
position, as shown in Figure 13, the fingers 160 are caused to
ride upon the inclined surface of the shaft portion, and are
moved radially inwardly to the releasing positions thereof.
In Figures 14 and 15, the design of the shaft por-
tion of 48c, as well as the fingers or bobbin engaging means
160' is so selected so that the fingers 160' are in their
extended, locking positions when the primary locking element
or actuatable member is locked in the extended position as
is the case in Figure 11. However, in this embodiment, the
cb/ - 26 -
1~:)6~8~
springs 156 are not placed in a state of compression in the
normal, locking positions of the fingers 160'. The arrange-
ments shown in Figures 10, 11, 14 and 15 utilize the fail-
safe locking devices as described above wherein the primary
locking members or el'ements are locked in the extended posi-
tions thereof. In connection with the embodiment or arrange-
ment shown in Figures 12 and 13, the locking device must be
modi,fied as suggested above to lock the primary locking ele-
ment or shaft portion lOb in the retracted position thereof.
In the description of bobbin supporting shafts
incorporating the fail-safe device of the present invention,
the shafts have all been shown ~Figures 10-15) as being
normal to the axis of rotation of the tubular frame 1~8.
However, this description was only by way of illustration,
and clearly, the fail-safe locking device can be used on
any cantilevered shafts of a reel supporting system. This
includes reel supporting shafts normal, parallel or at any
intermediate angular inclination relative to the axis of
rotation of the machine. The same is true of the reel engag-
ing means which are shown in Figures 10-15 and described above
It will become evident to any artisan skilled in the art
that the basic fail-safe locking device may be made to cooper-
ate with numerous types of reel engaging means, pintles and
the finger or prong arrangements shown being only illustrative~
- In the pintle assemblles 10 and 10' described abovet
the locking elements, namely the balls 114, were fully contained
within the pintle assemblies and the auxiliary or secondary
actuatable members 90, 90' were similarly contained therein.
Fluid pressure was applied directly to the pintle assemblies
to act upon both the primary as well as the secondary actuat-
able elements. In Figure 16, there is shown an alternate
arrangement of the present invention, wherein the pintle
- 27 -
1C~6~7B~3
assemblies 162 cooperate with external fluid pressure cylinders
164 to which the tubing 136 of the fluid pressure system is
connected. As will now be described in connection with
Figures 17-24, the fluid pressure cylinders 164 are actuatable
to physically move a piston plunger, rod or bar 166 which
cooperates with the pintle assembly 162 to provide the fail-
safe locking feature.
Referring to Figures 17-20, the cylinder 164 is pro-
vided with end walls 16~ and 170, all of the walls of the
cylinder being securely connected to the cradle frame 14 by
any suitable means, such as by welding. The end wall 168 has
a hole therein for communication with the air line or tubing
136 while the end wall 170 has a suitably configurated and
dimensioned hole therein to permit slidable passage of the
piston plunger, rod or plate 166 as will be more fully described.
Within the cylinder 164, there is provided a piston
172 with a gasket or sealing element in the nature of an o-
ring to form a substantially fluid tight chamber for communi-
cation with the air line 136. A compression spring acts bet-
ween the piston 172 and the end wall 170 to urge the piston
upwardly to retract the plunger 166 as shown in Figure 19.
Application of fluid pressure in the air pressure system
sufficient to overcome the orces of the spring 176 extends
the plunger 166 to the position shown in Figure 18.
The plunger 166 is shown to include a small width
portion 166a connected to the piston 172 and a large width
portion 166b to form bearing edges 166c. While the thickness
profile of the plunger 166 is not critical, it is advantageously
in the nature of a generally flat planar body or plate.
Provided in the large width portion 166b is a passage-
way in the nature of an arcuate slot 178 as best shown in
Figures 18 and 19. The slot 178 is generally inclined to
cb/ - 28 -
1~647~3
define a lower left proximate end 178a and an upper right
hand remote end 178b as will be more fully described below.
In the embodiment of Figures 17-24, the pintle
assembly 162 includes a bifurcated actuatable member 180
having an inner cylindrical portion 180a and bifurcated arms
180b and 180c spaced from each other to define a channel 182
dimensioned to slidably receive the plunger or bar 166 as
best shown in Figures 17 and 20. The arms 180b, 180c are
provided with aligned holes 184 which receive a pin 186
which bridges the channel 182 and is captured within the
slot 178 for slidable movements therein.
Mounted on the cradle frame 14 is a cylindrical
shell 188 which reinforces the cradle support member 14 and
which is dimensioned to receive a bearing sleeve 190 having
inside dimensions to slidably receive the actuatable member
18Q. The bearing sleeve 190 is provided with an outward
flange 192 which is used to fasten the sleeve to the support
member 14 by means of any conventional means such as bolts.
The plunger 166 is mounted for linear and recipro-
cal movements along a direction which is substantially 90
offset from the axis of the bearing sleeve l90 aIong which
the actuatable member 180 is movableO The locking mechanism
includes the arcuate slot 178 and the pin 186 which comprise
cam means for translating the movements of the plunger 166
into corresponding movements of the actuatable member 180
along its axis. While the directions of movement of the
plunger 166 and the actuatable member 180 are offset from
each other by 90, this is not a critical angle and any suit-
able angle may be used as long as the cam arrangement provides
the requisite locking as will now be more fully described.
The 90 offset does in most instances preserve space since
the piston 172 can be housed inside the frame of the cradle
14.
cb/ - 29 -
~6478~
Referring to Fi~ure 18, the pintle assembly is
shown in its retracted or disengaging position. To disengage
the pintle 12 from the reel 26, fluid is applied under pressure
to the line 136, the pre~sure being applied to the piston 172
to extend the plunger 166 against the action or forces of the
compressiOn spring 176. Under these circumstances, the pin
186 is forced to the remote end 178b of the slot 178 to thereby
force the actuatable member 180 and the pintle 12 to the dis-
engaging position. Referring to Figure 19, when the fluid
pressure is removed, the compression spring returns the piston
172 to its retracted position, causing the pin 186 to move
to the proximate end 178a of the slot with attendant movement
of the actuatable member 180 and the pintle 12 to the reel
engaging position. While the slot 178 may have a smooth or
continuous curvature as shown by the solid lines in Figures 18
and 19, the slot advantageously is composed of two slot portions
as suggested by the dashed outline in these Figures. By form-
in~ the slots as suggested, greater forces are created by
the spring 176, on the one hand, and the fluid pressure, on
the other hand, when these forces are required for actual
insertion or removal of the pintle 12 from the reel. Move-
ments of the pintle prior to engagement require little forces,
and this can be utilized to advantage to provide greater
axial movements of the pintle should this be necessary.
Referring to Figure 18a, an important feature of
the-embodiment described in Figures 16-20 is that the proxi-
mate end 178a of the slot 178 defines a bearing surface A
for the pin 186 which is oriented to avoid any components of
force and movement of the pin within the slot toward the remote
end 178b upon application of axially outward forces F on the
actuatable member 180. It will be evident that by arranging
the bearing surface A normal to the axial force direction F,
cb/ _ 30 -
1C~6~78~
theoretically infinite axial forces can be produced without
moving the pin 186 and, therefore, possibly unlocking the
actuatable member 180. This provides the desired fail-safe
feature. Of course, failure of air pressure will not adversely
affect reel engagement since the spring 176 will continue to
maintain the pin 186 at the remote end 178a as shown in Figure
18a.
In order to enhance the fail-safe properties of the
system being described, it is possible to utilize a secondary
plunger of the type described in connection with Figures 1-15
which may be used in conjunction with the cylinder 164 to
po~itively lock the piston 172 in-its retracted position shown
in Figure 19. This is not believed to be necessary for most
applications. It is also possible to provide a notch or seat
in the region of the bearing surface A ~Fig. 18a) which will
further prevent inadvertent or accidental movement of the pin
186.out ~f the locking position at the proximate end 187a.
By actually providing a negative or xeverse inclination to
the bearing surface A, which. has a component which is perpendi-
cular to the axial direction which is directed toward theproximate end, application of axial forces to the pin 186
urges-the same to remain at the proximate end and avoids
movement of the pin in the slot from the locking to the releas-
ing positions.
Referring to Figure 18, the gap G between the pintle
12 and the reel 26 should be approximately equal to the axial
stroke width S between the proximate and remote ends 178a and
178b, so that movement of the pin 186 between the remote ends
results in full engagement and sufficient clearance on dis-
engagement to remove the reel.
It may be noted that while an arcuate slot 178 anda pin 186 have been shown and described as the cam for moving
cb/ - 31 -
.:
~;47~3~
and locking the actuatable member 180, it will be evident to
those skilled in the art tha-t other cam arrangements may be
used for this purpose as long as they provide adequate means
for positively locking the actuatable member in a fail~safe
fashion.
Also, it may be noted that while the pin 186 is
shown mounted on the actuatable member 180 while the slot is
provi.ded on the plunger 166, it is equally possible to inter-
change these and still achieve the same operation.
1~ As with the earlier embodiments, it is also possible
with'the embodiment of Figures 17-20 to arrange a spring to
normally move the plunger 166 to its fully extended position
instead of the'fully retracted position as described. This
can simply be done by positioning a compression spring bet-
.~een the piston 172 and the end wall 168. Pressure then has
to be bxought in on the other side of the piston 172 to retract
the'same.
Referring to Fi,gures 21-24, a still further embodi-
ment is illustrated which is similar, in many respects, to
th.e'embodiment shown in Figures 17-20. Again, an external
cxlinder 164 is used which is provided with a linearly mov-
ahle reciprocating shaft 166. Here, the actuatable member 194
, includes a passageway in the nature of a segment of a heIical
groove 194a which forms part of the cam and exhibits many
of the similar properties of the slot 178.
The cylindrical shell 188' is originally secured to
the cradle frame 14 and provided with an annular flange 188"
which extend~ radially inwardly and outwaraly o~ the cylindrical
shell for securing a rotatable pinion gear 196 and preventing
the same from axi.al movements. The pinion gear 196 is generally
cup shaped and includes a bearing sleeve 196a, and end plate
or disc 196b and connecting portion or web 196c which connects
cb/ 32 -
7~
the bearing sleeve and the pinion disc or plate. Formed on
the outer periphery of the pinion plate or disc 196b are gear
teeth 196d.
The actuatable member 194 is movable axially between
extended or retracted positions within the bearing sleeves 196a
to form a variable space lg8 between the actuatable member 194
and the plate or disc 196b.
The pinion gear 196 rotates about the axis of the
actuatable member but is fixed against axial movements.
As best shown in Figure 23, the end of the shaft 166
is, connected to a rack 200 by means of a carrying arm or connect-
iny member 202 which offsets the rack from the shaft 166 a
sufficient distance to cause meshing engagement of the xack
teeth 204 and the pinion gear teeth 196d.
A pin 206 is formed on the inside surface of the
bearing sleeve 196a which pin rotates with rotation of the
` pinior gèar 196. The pin 206 is captured within the groove
194a for movement between proximate and remote ends of the
groove similarly in the manner described in connection with
the slot 178. To assure that the actuatable member 194 does
not rotate about lts axis but only moves along its axial dir-
ections, there is advantageously provided a key way slot 194b
in the actuatable member, as best shown in Figure 22. A key
208 protrudes from the cylindrical shell and thereby assures
that the actuatable member does not rotate relative to the
cradle support member 14. While only one pin and groove have
been shown, it should be evident that two or more pins with
associated grooves may be utilized.
The operation of the embodiment shown in Figures 21-24
is generally similar to that of the embodiments of Figures 17-20
When fluid pressure is applied, referring to Figure 21, the
piston 172 is forced downwardly, as viewed in Figure 21, -
cb/ - 33 -
L7~3
against the action of the spring 176 to extend the shaft 166.
Movement of the rack 200. causes rotation of the bearing sleeve
196a and movement of the pin to the remote end of the groove
.
1.94a th.us disengaging the pi.ntle 12 from the reel 26. When
the pressure is released, the spring 176 returns the shaft
166 to its retracted position, causing the rack 200 to rotate
the pin 206 until it is moved to the proximate end of the
groove which represents a stable or locked position wherein
the actuatable member and the pintle are in the reel engaging
position.
The embodiments disclosed in Figures 16-24 utili~e
a single biasing means or spring, as opposed to the multiple
springs in the other -em~odiments described. Where a single
spring is used, spring action may be offset 90 from the longi-
tudinal or axial direction of the actuatable members which
carry the pintles. Such arrangements offer the advantage
that a part of the assembly may be housed within the frame
of the bobbin cradle 14, thus minimizing the size of the lock-
ing assembly and the space required.
.
The above-described embodiments of pintle assemblies
are only illustrative of the basic principle of the present
invention. Numerous modificatlons of the described constructions
may be made while still practicing the invention as defined
in the appended claims. For example, while the bearing sur-
faces against which the fluid medium under pressure is applied
ha.ve been shown as being disposed or provided on piston por~
tions or on annular lips or wall portions of such pistons, the
fluid medium can be applied to the slidably mounted pistons
- or plungers in other conventi~nal manners. Also, while the
primary locking elements and the safety plungers have been
shown to be telescopically arranged in the presen-tly preferred
embodiments so that application of fluid medium under pressure
cb/ - 34 -
" 1~647~3
changes the overall effective lengths of the actuatable
members,this is not, in and of itself, a critical feature of
the presentinvention and any other arrangement of the slidably
mounted pistons or plungers which achieves the functions above-
described can be used.
The present invention contemplates other modified
constructions which automatically, by action of hydraulic
or pneumatic pressure, provide positive locking action, this
irrespective of the specific mechanical constructions which
have been described above. It is easy to see, for example,
that the system could be reversed using compressed air to
close the pintle assembly to move the primary locking element
to the extended position, while utilizing the action of the
compression springs to open it or move the primary locking
element to the retracted or releasing position. However, in
~uch a case, the locking sy$tem would be continuously under
~tress since it would have to counteract the force of the
spxing which tends to open the spindle. In this situation,
a failure of the locking system would cause an accident while
in the a~ove-described arrangements it would not.
- While the fail-safe locking device for xeel carrying
sys~ems has primarily been described above in connection with
pintle assemblies of the type commonly used on cradles in
tubular-type stranders, it should be evident from the above
description that the fail-safe locking devices may be utilized
in other reel carrying systems whenever a reel or bobbin is to
be securely and releasably and positively locked in place.
More specifically, the reel engaging means cooperating with the
primary locking element 46 in the embodiments shown in Figures
1-~ is in the nature, of a pintle mounted on the shaft portion
4~ of the primary locking element 46. Flowever, numerous other
applications exist where engaging means other than pintles may
cb/ - 35 -
~L~6gL~8~3
be mounted on and cooperate with the shaft portions 48 of the
locking device 10.
It is to be understood, therefore, that the foregoing
des.cription of the various embodiments illustrated herein is
exemplary only, and various modifications to the embodiments
shown herein may be made without departing from the spirit
7 and scope of the i.nvention.
,
cb/ - 36 -
