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Патент USA US3072404

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Jan. 8, 1.963
T. L. URQUHART
I
3,072,394
OPERATING SYSTEM FOR MULTI-LEAF DOORS
Filed May 25, 1959
I
3 Sheets-Sheet 1
FIGJ.v
)IA/IV‘ENTOR. ;
THO-R TON LMRQUHART
ATTORNEYS
Jan. 8, 1963
1-. 1_. URQUHART
3,072,394
OPERATING SYSTEM FOR MULTI-LEAF DOORS
Filed May 25, 1959‘
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Jan. 8, 1963
1'. L. URQUHART
3,072,394
OPERATING SYSTEM FOR MULTI-LEAF' DOORS
Filed May 25, 1959
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XI
' 5 JWEIYTOR
THORNTdN-LUROUHART
BY 40%
ATTO NEYS
United States Patent
,.
ME
Patented Jan. 8, 1963
2
1
3,ti72,394
Thornton L. Urquhart, Farmington, Mich, assignor to
Byrne Doors, Inc, Ferndale, Mich, a corporation of
Michigan
()PERATWG SYSTEM 136R MULTI-LEAF DOORS
Filed May 25, 1959, Ser. No. 815,420
2 Claims. (Cl. 268-48)
The invention relates generally to door operating sys
tems and refers morespeci?cally to apparatus for mov
doors including a centrally located traveling carriage hav
ing anti-friction members mounted thereon, anti-friction
members ?xedly secured on both sides of said doors, a
single continuous linear member mounted on the anti
friction members, and a single drive means for said linear
member located at one side of the doors, and capable
of moving all the leaves of the divided sliding doors
simultaneously so that they arrive at their fully open or
fully closed position at the same time.
Still more speci?cally it is an object of the present in
vention to provide door operating apparatus for centrally
ing centrally divided multi-leaf sliding doors to open and
divided multi-leaf sliding doors including a traveling
closed positions including a centrally located traveling
sheave carriage slidably mounted on a track over said
carriage having anti-friction members mounted thereon
doors, ?xed sheaves at each side of said doors, a single
acting in cooperation with a single continuous linear
member, ?xed anti-friction members located on opposite 15 continuous cable, the ends of which are secured at oppo~
site sides of said doors, passing in a plurality of strands
sides of the multi-leaf sliding doors, and drive means for
the continuous linear member to simultaneously move
said doors so that they arrive at a full closed position
centrally of an opening to be closed or at a full opened
position on opposite sides of said opening at the same 20
time.
~
In the past, relatively wide, high openings such as the
entrance openings to airplane hangars, factories, Ware
houses and the like, have been closed by doors formed
of a plurality of leaves which were movable on guides or 25
tracks simultaneously at ditferent rates to arrive at a fully
open or fully closed position at the same time. Such
doors have however been subject to the criticism that
between said ?xed sheaves and said traveling sheave car
riage, each leaf of said doors being attached to separate
strands of said cable for movement therewith and means
located at one side of said doors to impart movement to
the cable, whereby said door leaves are caused to simul
taneously move between fully open and fully closed po
sitions on movement of said cable and to arrive at said
positions together.
These and other objects, advantages and novel details
of construction of this invention will be made more ap
parent as this description proceeds, especially when con
sidered in connection with the accompanying drawings,
wherein:
heavy operating mechanism therefor was required in the
‘FIGURE 1 is a perspective view of a centrally divided
space above the doors which greatly increased the cost 30
multi-leaf door operating system according to the inven
of the structure wherein the doors were installed, that
tion.
the operating mechanisms for the doors were not suf?ci
FIGURE 2 is a top view of the door operating system
ently protected from dirt, snow and the like, and that the
of FIGURE 1.
opening and closing thereof was not uniform.
Furthermore, many multi-leaf doors of the size re 35
quired to close the high wide openings under considera
FIGURE 3 is a partial front elevation of the door op
erating system of FIGURE 1.
tion have in the past been attached to a single side of an
FIGURE 4 is a front elevation of a bracket used to
to individual leafs of said doors.‘ Such construction ne
cessitates the traveling of at least one leaf of the door
over the full width of the opening or requires duplication
URE 4 taken in the direction of the arrow 5 in FIGURE
4
FIGURE 6 is a cross-section of the traveling sheave
attach the cable of the door operating system of FIGURE
opening to be closed and have been operated by means
1 to the individual leaves of the doors.
positioned at the said single side of said opening and
FIGURE 5 is a side elevation of the bracket of FIG
cables attached to a plurality of idividual pulleys secured 40
of the multi-leaf doors and the operating mechanism
therefor on each side of the opening so that the end leaves 45
of a pair of doors meet in the center of the opening. The
duplication of the operating means on opposite sides of
the opening is of course expensive. When one leaf of the
door is required to travel the full width of the opening
the time required to open or close the door is often exces
sive. Also the operation of multi-leaf doors wtih a
plurality of cables attached to a plurality of pulleys or
drums or sheaves attached to individual leaves of the door
carriage of the door operating system of FIGURE 1.
FIGURE 7 is a longitudinal section of the traveling
sheave carriage of the door operating system of FIGURE
1 taken on the line 7—7 in FIGURE 6.
One embodiment of the door operating system of the
invention will now be described with particular refer~
ence to the ?gures of the drawing.
The door operating system of the invention generally
indicated it) shown in FIGURE 1 comprises a diagram
matically illustrated sheave carriage, generally indicated
12 and centrally located with respect to a pair of cen
multiplies the chance of malfunction of the operating
mechanism.
55 trally divided, multi-leaf doors generally indicated '28
Therefore it is one of the objects of the present inven
tion to provide a door operating system for centrally
divided multi-leaf sliding doors which is compact, light
weight, uncomplicated and capable of moving all the
and 3t), anti-friction members or sheaves 14, 16, 18 and
2t) rotatably mounted on the sheave carriage 12, pairs
‘of anti-friction members or sheaves 21 and 22, and 24
and 26 secured for rotation in a ?xed position at the
leaves of the divided sliding doors simultaneously so that 60 opposite sides 29 and 31 respectively of an opening 33
in a building structure 35 which is to be closed by doors
they arrive at their fully open or fully closed position at
28 and 30. A continuous linear member or cable gen~
erally indicated 32 reeved on each of the above indicated
sheaves and passing therebetween in a plurality of indi
for centrally divided multi-leaf sliding doors ‘which may
be economically located in a position o?ering maximum 65 vidual strands as shown is also provided as an operating
the same time.
Another object is to provide door operating apparatus
protection therefor.
Another Object is to provide door operating apparatus
part of the door operating system of the invention. Drive
means for the cable 32, generally indicated 34 is located
adjacent side 29 of the building opening and is con
for centrally divided multi-leaf sliding doors which is so
nected in driving relation to sheave 22 as shown. Brack
constructed that uniform movement of the individual
door leaves is assured.
70 ets 36, 38, 4t) and 4-2 are provided as shown in FIGURE
1 to connect the individual leaves 44, 46, 48 and 50 re
More speci?cally it is an object to provide door operat
spectively to individual strands of the cable 32.
ing apparatus for centrally divided multi-leaf sliding
3,072,394
4
With the door operating system arranged as shown in
the FIGURES, the individual leaves 44, 46, 48 and 50 of
journaled in the downwardly extending frame members
the doors 28 and 38 will move simultaneously to the open
position at the sides 29 and 31 of the opening 33 in the
building structure 35 and arrive thereat at the same time
on clockwise rotation of sheave 22 caused by drive means
80 and 82 as shown. Slots 94 and 96 are provided in
pins 90 and 32 respectively as shown best in FIGURE 6
to receive locking plates 98 and 100 which prevent pins
94 and 86 from rotating or moving laterally with respect
34. Similarly on counter clockwise rotation of sheave 22
the doors 28 and 33 will move as shown in FIGURE 1
to the carriage 12. The locking plates 98 and 100 are
secured to the downwardly extending member 80 of frame
turn mounted on pins 90 and 92 respectively which are
under the in?uence of the operating system 16 from an
60 by means of bolts 102. In operation of the doors 2S
open position to the position indicated in FIGURE 1.
10 and 31) on rotation of the drive means 34, the carriage
The doors 28 and 30 as best shown in FIGURE 1 in
12 will be caused to slide within the guide and support
clude leaves 44 and 46, and 48 and 511, respectively. In
means 52 a distance equal to half of the distance traveled
operation the doors 28 and 30 are caused to separate cen
by the slowest moving door leaves 44 and 50 as will be
trally as shown at 51 and slide in opposite directions into
subsequently explained.
conventional door pockets (not shown) in a building 15
The sheaves 21 and 22 as shown diagrammatically at
structure 35. In the fully opened position the leaves 44
the right in FIGURE 1 are mounted on a shaft 104 as
and 46 and the leaves 48 and 50 of the doors 28 and 30
indicated. The shaft 104 must be rotatably secured to a
are adapted to overlap each other in the well known
?xed object such as the building structure 35 in a position
manner of multi-leaf sliding doors. The doors 28 and
as shown by convenient means (not shown). The sheave
38 are shown in FIGURE 1 in substantially their fully
21 is mounted for free rotation on shaft 104. Sheave 22
closed position. (Ionventional guide tracks (not shown)
is ?xedly attached to shaft 104 for rotation therewith.
may be provided to guide the doors 28 and 3%} in their
Sheaves 24 and 26 are mounted at the left of doors 28
movement between their open and closed positions in a
and 30 on shaft 196 for free rotation thereon. Shaft 106
‘particular installation. Likewise conventional anti-fric
must also be ?xedly supported for rotation by convenient
tion means may be attached to the doors 28 and 30 to
means (not shown) which may be secured to the building
facilitate their sliding movement during operation. Since
the basic nature of centrally divided multi-leaf sliding
structure.
doors as outlined above is well known the doors have
thereof ?xedly attached to the building structure 35 by
‘been indicated only diagrammatically in the ?gures and
means of a clamp 183 at the right side of doors 28 and
30 as shown in FIGURE 1. The cable 32 then passes
will not be described in further detail herein.
The doors 28 and 30 shown in FIGURE 1 are verti
cally mounted for horizontal sliding to open and close a
large opening in a building structure 35 such as an air
The cable 32 as best shown in FIGURE 1 has one end
between the clamp 168 and sheave 18 on carriage 12 in
a strand 110 and is then reeved on sheave 18 in an up
plane hangar. According to the invention, in such an
ward direction as shown. The cable 32 then passes be
tween the sheaves 18 and 21 in a strand 112 and is
installation support and guide means 52 as best shown in
reeved over sheave 21 in a downward direction.
FIGURE 6 must be provided for the traveling sheave
carriage 12 immediately above and parallel to the doors
114 of cable 32 then extends between sheave 21 and
sheave 20 and cable 32 is reeved over sheave 20 in an
28 and 38. The support and guide means 52 shown in
FIGURE 6 comprises an inverted structural channel
upward direction. From sheave 20, cable 32 extends in
strand 116 to sheave 22 and it is reeved therearound in
member 54 having structural angles 56 and 58 attached
to the downwardly extending ?anges thereof by conven
ient means such as welding in the manner shown.
The
support and guide means 52 may be designed and con
structed as an integral part of the building structure 35
in which the opening 33 to be closed by doors 28 and 30
is located. The support and guide means 52 will there
fore add little weight to the structural frame of the build
ing structure. Also, in the form shown, it will be noted
that the support and guide member 52 substantially com
pletely protects the traveling sheave carriage 12 from be
a downward direction.
Strand
The cable 32 then extends com
pletely across the top of both doors 28 and 38 in a strand
118 and is reeved around sheave 26 in an upward direc
tion.
In the manner above described, cable 32 then is ex
tended between sheaves 26 and 16, between sheaves 16
and 24, and between sheaves 24 and 14 in strands 120,
122 and 124. The cable 32 then extends from the bottom
of sheave 14 to clamp 127 at the left side of the doors
28 and 30 where it is ?xedly secured to the building struc
ture 35 as shown. Cable 32 may be composed of strands
coming clogged with dirt, snow or the like.
The traveling sheave carriage 12 as best shown in FIG
URES 6 and 7 includes a frame generally indicated 60
which may be built up of steel plate by welding in the
cord. In extremely heavy door installations part of the
illustrated and formica block (not shown) are symmetri
cally secured to the downwardly extending members 80
during the opening and closing thereof.
of steel or in some door installations may be of rope or
strands 116 and 118 of cable 32 may assume the form
of a chain which may be driven by sheave 22.
form shown. A pair of longitudinally extending formica 55
Brackets 36, 38, 40 and 42 are provided as shown in
‘blocks 62 and 64 are secured to the underside of the hori
FIGURE 1 to attach each of the separate door leaves
zontal member 66 of frame 60 by means of bolts 68 in
44, 46, 48 and 50 to the strands 122, 118, 116 and 112
the location shown. The blocks 62 and 64 provide a
respectively of cable 32. The brackets as shown are
bearing contact with angle members 56 and 58 to sup
rigidly secured to the respective door leaves and are
port the carriage 12 and permit longitudinal sliding 60 ?xedly attached to the indicated cable strands in the po
thereof within the support and guide means 52. Similar
sition shown in the drawings to provide positive drive
vertically extending formica blocks 72, 74, and 76 as
means for the individual leaves of the doors 28 and 30
The details of the brackets 36, 38, 40 and 42 are set
and 82 of frame 60 by means of bolts 84 to provide lat 65 forth in FIGURES 4 and 5. Each bracket consists of an
eral guide surfaces for the carriage 12 which will allow
sliding of the carriage 12 within the guide and support
L-shaped member 128 having a vertically extending leg
138 and a horizontal leg 132, a ?at plate 134 having three
means 52. Spacing shims 85 are provided between the
triangularly spaced threaded studs 135 extending from
formica blocks 72, 74, 76 and 78 and the downwardly
one side thereof and three annular disks 136. As shown
extending frame members 80 and 82 to properly space 70 the horizontal leg 132 of the L-shaped member 128 is
the formica blocks for sliding contact with the angle
adapted to be secured to the top edge of a door leaf by
members 56 and 58.
means of bolts 138. The vertically extending leg 130 of
Anti-friction members in the form of pairs of freely
the L-shaped member 128 is provided with triangularly
rotatable sheaves 14 and 16, and 18 and 21] are mounted
spaced studs 135 on the plate 134.
on thrust bearings 86 and 88 respectively which are in
In assembly the cable 32 is attached to the brackets in
3,072,394
6
the manner shown best in FIGURE 4. Disks 136 are
sleeved over studs 135 on plate 134. The cable 32 is
then wound around the annular disks 136 in the con
?guration shown in FIGURES 4 and 7 the studs 135 are
then inserted within the triangularly spaced openings 137
in the vertical leg 130 of the L-shaped member 128.
Lock washers 140 may then be placed over the ends of
studs 135 and the studs 135 may be secured within the
openings 137 and the circular disks 136 and plate 134
may be drawn tightly against the L-shaped member 128
by means of nuts 142 threadedly engaged with studs 135.
of sheave 22 that as sheave carriage 12 moves to the right
one-half a leaf width that leaf 48 of door 30 will move
to the right two full leaf widths and leaf ‘50 of door 30
will move to the right one full leaf width. At the end of
this travel, leaves 48 and 50 will completely overlap each
other and will be in the fully open position at the right
side 31 of the opening 33 in the building structure 35.
In order for the sheave carriage 12 to advance toward
the right in FIGURE 1, it will be understood that the
strands 120, 122, 124 and 126 must be lengthened. Since
struction just described the cable 32 is securely gripped
between the plate 134 and the vertically extending leg
the cable 32 is ?xedly secured to the building structure
at 127, the cable necessary to lengthen the strands 122,
120, 124 and 126 of cable 32 to permit carriage 12 to
move to the right must be obtained due to the short
ening of strands 11th, 112, 114 and 116 of cable 32
130 of the L-shaped member 128 when the nuts 142 are
through the strand 118 of cable 32 extending between the
The disks 136 as shown are of slightly less thickness
than the diameter of cable 32. Therefore, in the con
drawn tight. The length of the vertically extending leg
driven sheave 22 at the right side of the doors 28 and 3t}
and the sheave 26 at the left side of the doors.
130 of the L-shaped member 128 may be chosen to suit
As previously stated a length of cable equal to two
the relative elevation of the particular strands of cable‘
32 which it is desired to grip with the bracket. It will 20 leaf widths of doors 28 and 30 will be allowed to pass
over sheave 22 on horizontal movement of carriage 12
also be understood that the relative location of the
one-half leaf width. Since each of the strands 120, 122,
brackets 36, 38, 40 and 42 on the door leaves 44, 46,
124 and 126' must be lengthened by one-half leaf width
48 and 50 may be varied to suit the conditions of the
in order to allow the carriage 12 to move to the right
particular installation.
one-half leaf Width, all points on strand 118 of cable 32
The drive means 34 for the door operating system‘of
including that point at which the bracket 38 is attached
the invention as indicated best in FIGURE 1 includes
thereto must move to the right two full leaves widths.
a drive motor 144 which is capable of imparting both
Also, since each of strands 124 and 126 must be length
clockwise or counter-clockwise rotation to a driven sheave
ened one-half leaf width, each point on strand 122 of
146, and an endless belt 148 for transferring the relative
cable 32 including the point at which bracket 36 is at
rotation of the sheave 146 to a driving sheave 150 at
tached thereto must move to the right one full leaf width.
tached to shaft 104 for rotation therewith. As will sub
It will be seen then that as the carriage 12 moves to
sequently be explained, clockwise rotation of sheave 146
the right one-half a leaf width that the leaves 44 and 46
and motor 144 will cause doors 28 and 30 to assume an
attached to the strands 122 and 1.18 of cable 32 respec
open position. Subsequent counter-clockwise rotation of
sheave 146 will cause doors 28 and 30 to assume a closed
tively will move to the left one full leaf width and two
position substantially as shown in FIGURE 1. As shown
full leaves widths respectively and assume an overlapping
the drive means 34 is located on the right side of the cen
trally divided doors 28 and 30 in a protected position at the
top of the doors. It will be understood that other
locations for the drive means 34 are possible.
40
As indicated above, clockwise rotation of motor 144
will cause sheave 146, sheave 150, shaft 104 and sheave
22 which is connected to shaft 104 for rotation there
and completely open position. It will further be noted
that the leaves 44 and 46 arrive at their fully open posi
tion at the same time that leaves 48 and 50‘ arrive at the
fully open position and that during this time the traveling
sheave carriage 12-has moved to the right one-half the
width of one leaf of doors 28 and 30 due to clockwise
rotation of sheave 22 by drive means 34.
As sheave
In a similar manner, counterclockwise rotation of
22 is rotated in a clockwise direction the cable 32 is
caused by frictional forces to move around sheave 22 in
the direction indicated by the arrow heads on strands 116
and 118 of the cable 32. As will be evident from an in
sheave 22 by drive means 34 will cause a shortening of
the strands of cable 32 on the left side of the doors 28 and
30 and a similar lengthening of the strands of cable 32 on
the right side of the doors 28 and 30 resulting in a move
ment to the left of carriage 12 of one-half of one leaf
with to also rotate in a clockwise direction.
spection of FIGURE 1, movement of the cable 32 around
the sheave 22 in a clockwise direction will tend to move
the traveling sheave carriage 12 in a rightward direction
as indicated by arrow 152. Movement of carriage 12
in the direction of arrow 152 will allow strands 110, 112,
114 and 116 of cable 32 to shorten.
For example, if the traveling sheave carriage 12
moves a distance to the right equal to one-half of the
width of one of the door leaves each of the strands 110,
112, 114 and 116 of the cable 32 will be allowed to
shorten an equal amount. A length of cable equal to
width to substantially the position shown in FIGURE 1.
The individual leaves of doors 28 and 30 will on such
movement to the left of the sheave carriage 12 assume
the fully closed position illustrated in FIGURE 1 in a
manner similar to that described above in which the
leaves 46 and 43 travel twice the distance that leaves 44
and 50 travel in the same length of time.
While the particular embodiment of the invention de
scribed concerns double leaf centrally divided vertical
doors sliding horizontally it will be appreciated that the
the combined length of the shortening of these four strands 60 invention herein disclosed may be applied to vertically
sliding doors and to centrally divided sliding doors hav
of cable 32 will therefore be available to pass around
ing more than two leaves. The applicant does not there
sheave 22 in a clockwise direction during such movement
fore wish to be limited in the practice of the disclosed
of the carriage 12. The point on strand 116 of cable
invention to that embodiment thereof set forth in the
32 to which bracket 40 is attached will therefore, be
moved to the right four times the distance that the sheave 65 drawings.
What I claim as my invention is:
carriage 12 moves to the right, that is, two full leaf
1. An operating system for a door movable to fully
widths. Since a length of cable equal to the combined
length of the shortening of strands 110 and 112 of cable
closed and fully open positions respectively and having
plural leaves simultaneously differentially movable to
32 on movement of carriage 12 will pass clockwise around
sheave 21 with cable 32 mounted as shown, all points 70 arrive simultaneously at fully closed and fully open po
sitions, means for moving said door to fully closed and
on strand 112 including the point at which bracket 42 is
fully open positions by simultaneous differential move
attached thereto must move to the right twice the dis
ment of the leaves thereof including a ?rst plurality of
tance that carriage 12 moves to the right or in the as
sembly illustrated one leaf width of doors 28 and 30.
rotatable members and a second plurality of rotatable
It will be understood then that on clockwise rotation 75 members ?xedly mounted in spaced relation to each
3,072,394
27
8
other, a carriage between said ?rst and second pluralities
of rotatable members movable in opposite directions
along a predetermined path, third and fourth pluralities
relation to each other, a carriage ‘between said ?rst and
second pluralities of rotatable members movable in
opposite directions along a predetermined path, third
of rotatable members mounted on said carriage, a ?ex
ible linear member having anchored ends and a con
and fourth pluralities of rotatable members mounted on
CI said carriage, a ?exible linear member having‘anchored
tinuous section extending ?rst from one of the anchored
ends and a ?rst continuous section extending ?rst from
ends alternately and successively in reeved relation
one of the anchored ends alternately and successively
around separate rotatable members of said third and
in reeved relation around separate rotatable members
?rst pluralities respectively to form a plurality of pairs
of said third and ?rst pluralities respectively to form a
of portions of said section which extend from the car 10 plurality of pairs of portions of said section which ex
tend from the carriage in one direction of carriage
riage in one direction of carriage movement, said linear
member having a second continuous section extending
movement, said linear member having a second con
tinuous section extending from a rotatable member of
from a rotatable member of said ?rst plurality alter
said ?rst plurality alternately and successively in recved
nately and successively in reeved relation around sep
arate rotatable members of said second and fourth 15 relation around separate rotatable members of said
second and fourth pluralities respectively, and ?nally
pluralities respectively, and ?nally from a rotatable
from a rotatable member of said fourth plurality to
member of said fourth plurality to the other of said
the other of said anchored ends to form a plurality of
anchored ends to form a plurality of pairs of portions
pairs of portions of said second section which extend
of said second section which extend from the carriage
in the opposite direction of carriage movement, move 20 from the carriage in the opposite direction of carriage
ment of said linear member causing said carriage to
movement, movement of said linear member causing
said carriage to move along its path and causing sep
move along its path and causing separate portions of
said sections to move at different speeds in the same
arate portions of said first section to move at different
direction, means connecting the leaves of said door
respectively to certain of the said separate portions, and
means for moving said linear member in opposite di
rections to simultaneously differentially move the leaves
of said door and thereby move said door to ‘fully closed
or fully open positions depending on the direction of
speeds in one direction and separate portions of said
second section to move at di?erent speeds in the op
posite direction, means connecting the leaves of one
door respectively to said separate portions of said ?rst
section, -means connecting the ‘leaves of the other door
to said separate portions of said second section, and
movement of said linear member.
30 means for moving said linear member in opposite di
2. An operating system for a pair of doors movable
rections to simultaneously move the leaves of said doors
toward and away from each other along a predetermined
and thereby move said doors to fully closed or fully
path to fully closed and fully open positions respectively
open position depending on the direction of movement
and each having plural leaves simultaneously differen
of said linear member.
tially movable to arrive simultaneously at fully closed 35
References Cited in the ,?le of this patent
and fully open positions, means for simultaneously mov
UNITED STATES PATENTS
ing said doors toward and away from each other to fully
closed and fully open positions by simultaneously dif
678,422
Poulson _____________ __ July 16, 1901
ferential movement of the leaves thereof including a
?rst plurality of rotatable members and a second plu
1,658,640
Huberty ______________ __ Feb. 7, 1928
1,904,588
rality of rotatable members ?xedly mounted in spaced
2,599,747
Weinberg ____________ __ Apr. 18, 1933
Craigon ____________ __ June 10, 1952
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