U.S. patent number 3,708,074 [Application Number 05/162,941] was granted by the patent office on 1973-01-02 for steel racking apparatus.
This patent grant is currently assigned to Steel Storage Systems, Inc.. Invention is credited to Thomas D. Fahey, Samuel Schlagel.
United States Patent |
3,708,074 |
Fahey , et al. |
January 2, 1973 |
STEEL RACKING APPARATUS
Abstract
This invention relates to an apparatus for racking structural
steel stock characterized by at least two upstanding
partition-forming wall sections interconnected in
longitudinally-spaced parallel relation. Each of these wall
sections carries one or more upwardly-opening saddles which, along
with the carriage atop which it is mounted, defines a cradle
movable relative thereto in load-supporting relation between a
retracted and an extended position. A common
longitudinally-extending crankshaft interconnects two or more of
the longitudinally-aligned cradles together for simultaneous
movement so as to produce therewith an open-ended top-loading
drawer adapted to support structural steel members and the like at
spaced points therealong. In the preferred embodiment, the cradle
carriages rest atop the crankshaft in frictional engagement
therewith while in two alternative embodiments, the crankshaft is
operatively connected to the cradle by a meshed rack and pinion. In
one of the latter embodiments, a separate crankshaft is provided
for each drawer while in the other an axially-movable shaft is
selectively connectable to a pair thereof.
Inventors: |
Fahey; Thomas D. (Denver,
CO), Schlagel; Samuel (Denver, CO) |
Assignee: |
Steel Storage Systems, Inc.
(Commerce City, CO)
|
Family
ID: |
22587765 |
Appl.
No.: |
05/162,941 |
Filed: |
July 15, 1971 |
Current U.S.
Class: |
211/151; 211/162;
312/286; 312/334.14; 312/334.19 |
Current CPC
Class: |
B65G
1/026 (20130101); A47B 46/00 (20130101) |
Current International
Class: |
A47B
46/00 (20060101); B65G 1/02 (20060101); A47f
003/96 (); A47f 005/00 () |
Field of
Search: |
;211/151,162,6R,49R,1.5
;214/10.5,6R ;312/286,346,347,331,343,319,350,119,102 ;108/143 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
Primary Examiner: Britts; Ramon S.
Claims
What is claimed is:
1. The steel storage rack which comprises: two or more upstanding
partition-forming wall sections mounted in fixed-spaced parallel
relation to one another, two or more of said sections having one or
more rails mounted thereon, one or more rails of each section lying
in longitudinally-spaced parallel relation to at least one rail of
at least one other section to define at least a pair thereof, the
rails of each pair including load-bearing means defining an
upwardly-facing horizontal running surface and a downwardly-facing
running surface paralleling the latter located therebeneath; a
carriage mounted on each rail of the pair for independent
longitudinal movement relative thereto in transversely-spaced
parallel relation to one another, said carriage including upper and
lower rigid arms connected together at their near ends
vertically-spaced relation to define a gap therebetween sized to
receive the load-bearing means and a pair of anti-friction members
carried by said arms for movement therewith in rolling engagement
with the running surfaces of said load-bearing means, said
anti-friction members being positioned to cooperate with one
another and resist a load displaced toward the near end of the
carriage tending to tilt the latter downwardly; a pair of upright
posts fastened to the upper arm of the carriage so as to cooperate
therewith to define an upwardly-opening generally U-shaped saddle
adapted to cradle a load lowered therein; roller means journaled
for rotation adjacent the near end of the rail in supporting
relation to the underside of the carriage; and, means operatively
interconnecting two or more carriages together for simultaneous
movement in the same direction between a retracted and an extended
position, said means cooperating with said carriages and with the
cradle-forming saddles atop thereof to produce an open-ended
drawer.
2. The steel storage rack as set forth in claim 1 in which: the
anti-friction member on the lower of the carriage arms is spaced
farther from the near end thereof than the other of said members
carried by the upper arm.
3. The steel storage rack as set forth in claim 1 in which:
stop-forming means are carried by the rail and carriage in position
to interengage and limit the extended position of the latter.
4. The steel storage rack as set forth in claim 1 in which: the
means operatively interconnecting the carriages for simultaneous
movement comprises a shaft connecting the carriage-supporting
rollers together for conjoint rotation.
5. The steel storage rack as set forth in claim 1 in which: the
means operatively interconnecting the carriages together for
simultaneous movement comprises a rack carried by each of said
carriages extending longitudinally thereof, a shaft journaled for
rotation between the partition-forming wall sections extending
transversely across said racks in juxtaposed relation thereto, and
pinion gears mounted on said shaft for conjoint rotation therewith
in meshed engagement with each of said racks.
6. The steel storage rack as set forth in claim 1 in which: two or
more of the partition-forming wall sections include at least one
pair of rails mounted in side-by-side parallel relation at the same
level, one rail of one pair cooperating with a rail of another pair
at the same level to mount carriages extendible on one side of the
partition-forming sections while the remaining rails of said pairs
cooperate to mount carriages opening into extended position on the
opposite side of the latter.
7. The steel storage rack as set forth in claim 1 in which: two or
more partition-forming wall sections are provided with two or more
rails stacked one above the other in vertically-spaced parallel
relation, at least two rails at each level cooperating with one
another to mount the carriages of a single drawer.
8. The steel storage rack as set forth in claim 1 in which: the
lower carriage arm is substantially longer than the upper carriage
arm; the anti-friction members are mounted on the far ends of both
arms; and, stop means are carried by the rail and carriage located
to interengage upon movement of the latter toward extended position
so as to leave the anti-friction member carried by the upper
carriage arm in rolling load-supporting contact with the upper
running surface.
9. The steel storage rack as set forth in claim 1 in which: the
rail is of hollow rectangular configuration, the top wall of said
rail defining the load-bearing means and the bottom wall thereof
comprising a second load-bearing means defining a second
upwardly-facing running surface positioned to receive the
anti-friction member on the far end of the lower carriage arm for
rolling engagement atop thereof when telescoped within said
rail.
10. The steel storage rack as set forth in claim 1 in which: the
partition-forming wall sections include a centrally-located
vertical column with the rails mounted thereon in vertically-spaced
parallel relation so as to project on opposite sides thereof and
define crossarms; the lower arm of the carriage is of a length
adapted to extend to substantially the far end of the rail when in
retracted position and the upper arm thereof is substantially
shorter than the lower; and, in which the anti-friction members are
mounted at the far ends of their respective carriage arms.
11. The steel storage rack as set forth in claim 1 in which: the
rail includes a second horizontal load-bearing surface located in
fixed-spaced parallel relation beneath the first, said second
load-bearing surface defining a second upwardly-facing running
surface positioned to cooperate with the first and divide the load
on the carriage when a load is cradled in the saddle atop
thereof.
12. The steel storage rack as set forth in claim 2 in which: the
length of the rail is approximately twice the length of the drawer
supported thereon; and, in which the lower carriage arm is
approximately the same length as the rail upon which it rides.
13. The steel storage rack as set forth in claim 5 in which: the
lower arm of the carriage projects a substantial distance beyond
the far end of the upper arm thereof; the shaft and pinions carried
thereby are journaled for rotation beyond the far end of the upper
carriage arm when the latter is in retracted position; and, in
which the rack is mounted atop the projecting portion of the lower
carriage arm.
14. The steel storage rack as set forth in claim 6 in which: the
carriages supported for extendible movement in opposite directions
on each side-by-side pair of rails include overlapping extensions
paralleling one another in the same horizontal plane; racks are
mounted on the overlapping extensions of each carriage; a single
crankshaft is journaled for rotational movement in juxtaposed
position to said racks and for horizontal axial movement in a
direction normal thereto; one pinion is mounted on the shaft for
both rotational and axial movement relative thereto in permanent
meshed engagement with each rack; and, in which clutch means are
carried by said pinions and shaft selectively operative in one
axial position of the latter to form a driving connection with a
set of two or more pinions meshed with the carriage racks of a
single drawer, and said clutch means being alternatively operative
in a second axial position of said shaft to form a driving
connection with a second set of two or more pinions meshed with the
carriage racks of another drawer opening onto the opposite side
while disengaging said first set of pinions.
15. The steel storage rack as set forth in claim 6 in which: two or
more partition-forming wall sections are provided with two or more
rails stacked one above the other in vertically-spaced parallel
relation, at least two rails at each level cooperating with one
another to mount the carriages of a single drawer.
16. The steel storage rack as set forth in claim 6 in which: the
carriages at the same level cooperate with the cradle-forming
saddles carried thereby and their respective crankshafts to define
back-to-back drawers opening in opposite directions.
17. The steel storage rack as set forth in claim 13 in which: the
upper load-bearing means includes a slot opening above the rack
therebeneath and the pinion engages the rack through said slot.
18. The steel storage rack as set forth in claim 14 in which: a
stationary portion of said rack carries means connectable to said
shaft for releasably locking same in either of its operative axial
positions.
19. The steel storage rack as set forth in claim 14 in which: the
shaft includes an externally-threaded section adjacent a fixed part
of the rack; an internally-threaded nut-forming element is carried
by said fixed part of the rack in threaded engagement with the
threaded shaft section; and, means for selectively fastening said
nut-forming element to said shaft and rack, said means when
activated to stay in fixed relation to said rack becoming operative
to shift the shaft axially between its operative positions upon
rotation thereof, and said means when connected to the shaft for
conjoint rotation therewith defining the drive coupling for
rotating same in either direction relative to the rack.
Description
The racking, storage and removal of relatively long, heavy steel
structural members and the like has always been a troublesome and
time-consuming job which, in most instances, eventually comes down
to a simple hand operation where one or more persons manually push
or pull the pieces one-at-a-time in and out of a pigeonhole rack.
The larger or longer pieces which cannot be handled manually even
with the aid of a crane are usually stored on the floor atop blocks
that provide the space for passing the crane sling therebeneath.
This, of course, is most wasteful of storage space in the warehouse
as the area above the steel thus stacked must be left clear for the
overhead crane. The shorter pieces capable of being handled
manually are, as previously stated, customarily pigeonholed
according to their type, size and length.
It has now been found in accordance with the teaching of the
instant invention that the many shortcomings of the above-described
and other methods of racking steel can, in large measure, be
eliminated through the use of the novel top-loading rack forming
the subject matter hereof. The present rack is made up of two or
more upstanding partition-forming wall sections that are
interconnected in fixed-spaced parallel relation. The number and
spacing of the partition-forming wall sections are determined by
the load and length of the structural members to be stored therein.
The actual open-ended top-loading drawers are formed by operatively
interconnecting the extendable cradles together for conjoint
movement in longitudinally-aligned relation by a common crankshaft.
One end of the rack is provided with a special end wall fitted to
carry the crank used selectively to turn the crankshafts which
operate the drawers. Two or more such drawer assemblies are
preferably located on each side of each storage rack, all of which
are independently accessible from an overhead traveling crane or
similar portable hoisting apparatus such as a forklift truck. All
of the cradle elements forming a part of a given drawer are
extended and retracted simultaneously by a crankshaft that remains
within the confines of the fixed supporting structure where it is
protected from damage. The drawers are bottomless, topless and
open-ended, the cradles merely supporting the steel at
longitudinally-spaced points along its length while confining it
against lateral movement.
In the preferred form of the invention, the crankshaft is held in
tight frictional engagement with the underside of the several
cradle carriages by the weight thereof along with the load carried
thereby. A second version of the invention moves the crankshafts to
a position over the upper running surface of the rail rather than
below and utilizes a rack and pinion to operatively interconnect
the crankshaft and long arm of the cradle carriage. Separate drives
are provided, however, for each of the drawers. In a third
embodiment of the invention, the crankshaft is centrally located
and axially-movable so that it can selectively engage and operate a
back-to-back set of drawers. In this latter embodiment, a novel
mechanical clutch arrangement connects the crankshaft with one
cradle carriage arm while disengaging it from the others.
It is, therefore, the principal object of the present invention to
provide a novel and improved structural steel storage rack.
A second objective of the invention herein disclosed and claimed is
to provide an apparatus for racking steel and the like which
includes a series of two or more longitudinally-aligned cradles
operatively interconnected by a common crank-shaft for conjoint
movement to define an open-ended top-loading drawer.
Another object of the invention herein disclosed and claimed is to
provide apparatus of the class described which virtually eliminates
the manual operations normally associated with storing steel in
pigeonhole racks.
Still another objective of the within described invention is the
provision of a rack which provides multi-level steel storage for
even those structural elements which ordinarily are too heavy to be
loaded by hand and therefore, are stored in single layers at or
near ground level.
An additional object of the invention forming the subject matter
hereof is to provide a steel storage rack that includes two or more
partition-forming wall sections that can be interconnected in
longitudinally-spaced parallel relation to define bays of any
desired length and load carrying capacity.
Further objects are to provide a steel storage rack that is simple,
inexpensive, safe, easy to operate, versatile, rugged, efficient,
trouble-free, dependable, easy-to-service, compact and even
somewhat decorative in appearance.
Other objects will be in part apparent and in part pointed out
specifically hereinafter in connection with the description of the
drawings that follows and in which:
FIG. 1 is a side elevational view of one of the partition-forming
wall sections of the structural steel storage rack, portions
thereof having been broken away to better reveal the interior
construction;
FIG. 2 is a side elevation, the center portion of which has been
broken away to conserve space, showing how two adjacent
partition-forming wall sections cooperate with one another to
define a bay;
FIG. 3 is a fragmentary section taken along line 3--3 of FIG.
2;
FIG. 4 is a side elevational detail to an enlarged scale showing
the construction of the cradle;
FIG. 5 is a still further enlarged fragmentary end view, portions
of which have been broken away and shown in section, revealing the
details of the crankshaft and hollow cradle rail subassemblies;
FIG. 6 is an end view of the rack to a reduced scale showing the
end wall structure journalling the crankshafts and the crank
selectively connectable thereto;
FIG. 7 is a fragmentary side elevation of the end wall, crankshafts
and crank of FIG. 6 and to the same scale as the latter;
FIG. 8 is a front elevation of the crank subassembly to a
greatly-enlarged scale, portions of the housing having been broken
away to reveal the interior construction;
FIG. 9 is a fragmentary side elevation to the same scale as FIG. 8
showing the crank mounted on one of the uprights of the end wall,
portions of the latter having been broken away and shown in
section;
FIG. 10 is a fragmentary elevation to the same scale as FIG. 8 and
FIG. 9 looking to the left at the latter so as to see the pin and
bracket retaining means for the crank as it would appear from the
inside of the end wall upright;
FIG. 11 is a fragmentary view similar to FIG. 1 but to a much
larger scale showing an alternative construction in which a rack
and pinion connection is used to form the operative connection
between the crankshaft and cradle carriage, portions of the rail
having been broken away and shown in section to better reveal the
interior construction;
FIG. 12 is a fragmentary top plan view of the alternative structure
of FIG. 11 and to the same scale as the latter, portions again
having been broken away to reveal the interior construction;
FIG. 13 is a fragmentary view much like FIG. 11 and to the same
scale showing a still further modified driving connection between
the cradle carriage and crankshaft, portions of the supporting rail
having once again been broken away to reveal the rack and
pinion;
FIG. 14 is a fragmentary top plan view much like FIG. 12 and to the
same scale but showing the modification of FIG. 13 with appropriate
portions broken away and shown in section; and,
FIG. 15 is a fragmentary section taken along line 15--15 of FIG. 14
revealing the mechanical clutch used to selectively engage one of
the pinions upon axial movement of the crankshaft.
Referring next to the drawings for a detailed description of the
present invention and, initially, to FIGS. 1 through 5 for this
purpose, reference numeral 10 has been chosen to broadly designate
the steel storage rack in its entirety while numeral 12 similarly
identifies the fundamental building blocks of the system, namely,
the upstanding partition-forming wall sections which, in the
particular form illustrated, are interconnected in fixed-spaced
parallel relation by spacers 14 and crossed diagonal struts 16. Two
or more longitudinally-extending feet 18 arranged in
transversely-spaced relation to one another cooperate with a
bedplate or the like 19 to provide a base atop which is mounted the
lowermost pair of several pairs of load-supporting rails 20 that
comprise a part of each partition-forming wall section. In the
particular form illustrated, the rails are mounted in side-by-side
spaced parallel relation. Each rail of the pair defines the
supporting structure upon which one of the cradle subassemblies
that have been broadly identified by reference numeral 22 rides as
it moves between its retracted position shown in full lines in FIG.
1 and the extended position thereof shown in phantom lines. One
rail carries the cradle emerging from the right side of the
partition-forming section 12 while its companion in the pair
carries the one that emerges from the left side. Obviously, if the
rack is located where access can be had to but one side thereof,
only a single rail 20 is needed at each level to accommodate the
cradle that emerges from such side.
Between the pairs of rails on the several levels rises a central
vertical supporting column 24. At each level above the first, the
rails define crossarms extending horizontally in opposite
directions from said central column and upon both faces thereof.
Atop the upper end of the column is mounted a fixed
upwardly-opening saddle consisting of a crossarm 26 with uprights
28 at opposite extremities thereof. This fixed cradle can, of
course, be loaded directly from above and it needn't, therefore, be
extendible in drawer-like fashion as is the case with the
others.
Projecting from the same faces of the column that carry the rails
are tubular brackets 30, two at the top and another two at the
bottom. Opposed pairs of these brackets on adjacent
partition-forming wall sections telescope into the opposite open
ends of the tubular spacers 14 which thus determine the
longitudinal spacing therebetween. The weight and stiffness of the
members to be loaded in the rack will, in most instances, determine
the width of the bays between partition-forming wall sections as
they, in turn, determine the unsupported lengths. Angle brackets 32
at the base and top of each column receive diagonal struts 16 which
cooperate with the spacers 14 to maintain the fixed-spaced relation
between the partition-forming walls.
An examination of FIG. 2 will reveal that all of the cradles 22 are
vertically aligned on both faces of the rack although, obviously,
they can be staggered from one side of the central column to the
other as they progress from top to bottom; however, since no useful
purpose would be served by so doing, the construction shown is
preferred from a standpoint of simplicity and standardization.
Permanently fastened alongside each rail 20 in spaced parallel
relation to one another so as to project beyond one of its ends are
a pair of identical mounting brackets 34.
Downturned ears 36 of these brackets 34 that project both beyond
and beneath the rail contain longitudinally-aligned openings 38 in
which are pressed or otherwise fastened shaft journals 40, all of
which is most clearly revealed in FIG. 5 to which detailed
reference will now be made. A stub shaft 42 is journaled for
rotation within bearings 40 and shaft collars 44 on said shaft bear
against the exposed faces of ears 36 and prevent relative axial
movement thereof. Fastened securely to the portion of stub shaft 42
lying between the bracket ears for conjoint rotation therewith is a
friction roller 46. The upper surface of this roller lies
essentially tangent to the plane of the lower upwardly-facing
running surface of the load-supporting rail so that the underside
of the cradle carriage 48 will ride atop thereof as shown when it
moves telescopically to and fro inside the latter.
Detachably fastened to the inside faces of the shaft-mounting
brackets 34 above the ears 36 depending therefrom are a pair of
stops 50 whose adjacent faces are spaced apart a distance less than
that which separates the corresponding surfaces of rail 20. A
second set of stops 52 (FIGS. 1 and 4) project from the sides of
the cradle carriage spaced intermediate the ends thereof in
position to engage stops 50 when the drawer subassembly that has
been broadly designated by reference numeral 54 lies in the
extended position shown in phantom lines in FIG. 1. Note that with
stops 50 and 52 engaged, slightly more than half of the cradle
carriage 48 still lies confined within rail 20 due to the fact that
a portion of this carriage which will be described in detail
presently is about the same length as the rail so as to extend all
the way to its other end while the drawer pulls out a distance
substantially less than half this distance. The net result is that
while the load 56 (FIG. 1) within the drawer when it is extended is
substantially overbalanced, the roller 46 and the lower of the two
wheels 58 journaled on the remote end of the cradle carriage which,
at this point, is rolling along the underside of the top wall of
the rail, define two widely separated load-bearing points easily
capable of resisting the tilting moment about the stub shaft 42.
Wheel 58 of the carriage is free to roll along the bottom running
surface of rail 20 until the point is reached where the center of
gravity of the loaded drawer moves outwardly beyond sleeve 46,
whereupon, the cradle tilts the fraction of an inch necessary to
lift wheel 58 into contact with the underside of the top wall of
the rail. On the other hand, as will be seen presently, wheel 58
may never contact the lower upwardly-facing running surface of the
rail which, therefore, is not absolutely necessary although
preferred. The corresponding cradle carriage for the drawer at the
same level on the opposite face of the rack includes a portion
running to and fro in parallel overlapping relation within the
companion rail on the other side of the column 24, the latter
structure being clearly revealed in FIG. 3.
The carriage has a long lower arm 59 that runs inside the box rail
20. An upright post 60 at the near end of this lower arm forms a
part of the upwardly-opening U-shaped saddle that is also a part of
the cradle 22. The upper arm 62 of the carriage is shorter than
lower arm 59 and it also functions as the bottom or base frame
member of the saddle. Upper and lower carriage arms 62 and 59 are
arranged in vertically-spaced relation so as to leave a
rearwardly-opening slot 64 therebetween sized to receive the top
horizontal wall 66 of the rail. Even with the lower carriage arm
supported from below as shown by the bottom wall of rail 20, the
slot 64 left between it and the upper arm 62 would likely close
under heavy loads causing the carriage to drop down onto the top of
the rail and thus resist free movement of the cradle between its
retracted and extended positions. To prevent this from occurring,
the far end of the upper carriage arm 62 is provided with the
second of the pair of carriage wheels 68 adapted to run along the
top or exposed surface of the top wall 66 of the rail as shown.
The only other element of cradle 22 that remains to be described is
rear upright post 70 which is attached in vertical position to the
far end of the upper carriage arm 62 adjacent the roller 69 carried
thereby. Front and rear posts 60 and 70 cooperate with the
connecting upper carriage arm 62 to define an upwardly-opening
generally U-shaped saddle adapted to receive the load 56 from above
and confine same against lateral movement relative thereto. With
the drawer unloaded, wheel 58 on the longer of the two carriage
arms will either by rolling along the upwardly-facing running
surface on the bottom wall of the rail or the wheel 61 on the upper
short carriage arm 62 will be rolling along the corresponding
running surface of the top wall 66 but seldom both. When heavily
loaded, on the other hand, both carriage wheels 58 and 68 will
likely be in rolling contact with running surfaces of the rail.
With the center of gravity of the loaded drawer on the inside of
roller 46, wheels 58 and 68 will likely be in contact with the
upwardly-facing running surfaces of the top and bottom rail walls;
whereas, with the load outside roller 46, these same wheels will be
in rolling contact with opposite running surfaces of the same rail
wall, namely, the top one 66.
Finally, before leaving FIGS. 1-5, it will be seen that each of the
several drawer subassemblies 54 comprises a longitudinally-aligned
series of two or more cradles 22 operatively interconnected for
simultaneous movement in the same horizontal direction by a common
crankshaft 72. The several axially-aligned stub shafts 42 of the
several partition-forming wall sections comprise sections of the
crankshaft 72 to which they are connected in driving relation by
shaft couplings 74. These shaft couplings allow for minor alignment
errors while transmitting the driving torque from section to
section. Thus, when the crank subassembly 76 which will be
described in detail presently in connection with FIGS. 6-10,
inclusive, is connected to a free end of the crankshaft and
employed to rotate same in the appropriate direction, the entire
drawer subassembly 54 which may be several bays long and include a
plurality of cradles will move in or out as a unit.
Next, with reference to FIGS. 6-10, inclusive, the crank
subassembly 76 together with the endwall structure identified
broadly by numeral 78 which supports same will now be described in
detail. This endwall, in the particular form shown, comprises a
frame that includes a pair of uprights 80, a counterpost 82 and
several horizontal crossframe elements 84 interconnecting the
latter at the level of each crankshaft 72. The endwall thus defined
is fastened in fixed-spaced parallel relation to the adjacent
partition-forming wall section 12 by the same type of spacers 14,
diagonal struts 16 and brackets 32 that are used between two of the
latter sections.
The free ends 86 of the crankshafts pass through openings 88 (FIG.
9) in the web of uprights 80 onto the outside surface of frame 78.
Each such shaft-receiving opening 88 is provided with at least one,
and preferably a pair, of companion openings 90 spaced vertically
therefrom. In the case of a pair of such openings 90, one is
located above and the other below the shaft as illustrated.
The projecting end 86 of each shaft 72 is squared-off or otherwise
shaped to receive the crank tool socket 92 of the crank subassembly
76. Now, depending upon the load that crankshaft 72 has to move, it
may be driven directly by a simple handcrank-like dogleg handle 94
of the assembly shown or, in the case of long heavily-loaded
shafts, it is preferred to interpose a speed reduction mechanism
indicated generally by reference numeral 96.
In the case just mentioned, reducer 96 includes a pair of spaced
parallel plates 98 defining a frame. The tool socket 92 is
journaled for rotation between these plates and it comprises the
hub of sprocket 100. A stub shaft 102 is journaled for rotation in
spaced parallel relation to tool socket 92 while mounting thereon
the smaller sprocket 104 for conjoint rotation therewith. The
projecting end of stub shaft 102 receives crank 94 and sprocket
claim loop 106 defines the operative driving connection between the
sprockets. By providing the crank subassembly with a speed
reduction ratio of somewhere around 2:1 or 3:1, the load on shaft
72 can be handled quite easily.
Now, the inner of the two plates 98 of the reducer is provided with
a guide pin 108 that fits into one of the guide pin openings 90
depending upon whether the crank subassembly is used right-side-up
as shown in full lines or upside-down as shown in phantom lines in
FIG. 6. By enabling the unit to be used upside-down near the floor,
clearance is provided to rotate the crank.
The remaining feature of the crank subassembly is U-shaped bracket
110 that slips around the upright 80 and cooperates with the guide
pin 108 to hold the unit in proper position. This bracket is, of
course, fastened permanently to the rear face of the inside plate
98 in spaced relation to pin 108.
The attention is now directed to FIGS. 11 and 12 where the first of
two alternative embodiments have been illustrated. In the preferred
embodiment just described, the crankshafts 72 run along the outside
faces of the rack and the cradle carriage rests atop thereof in
frictional driving engagement therewith. The only disadvantage to
this arrangement is the exposed position of these crankshafts which
renders them somewhat more vulnerable to damage from external
activities being carried on in the immediate vicinity of the rack
such as, for example, other steel-handling operations. Thus, while
the preferred embodiment of the rack is quite well protected
against damage from proper use, it is somewhat more vulnerable to
external steel-handling operations such as the movement of
forklifts, crane-supported loads, etc.
The embodiment 10m shown in FIGS. 11 and 12 obviates the
aforementioned problem by moving the crankshafts 72m in to the
central column 24. The stub shafts 42m are somewhat longer and are
journaled for rotation within bushings 112 that replace the ball
bearing journals 36 of the previously-described embodiment. These
stub shafts 42m are coupled in driving relation to shafts 72 by
shaft couplers 74 as before. Each such stub shaft, however, carries
a pinion gear 114 that turns with said shaft and within a slot 116
in the top wall 66m of slightly modified rail 20m.
While cradle 22m is modified slightly in unimportant details over
the one 22 shown in FIGS. 1-5, the only significant change lies in
the carriage 48m thereof, the lower arm 59m of which is reduced in
depth to accommodate rack 118 fastened atop thereof in position to
mesh with the pinion 114 carried by the stub shaft.
Thus, upon rotation of the crankshaft 72m, the rack and pinion
connection defines a direct mechanical drive operative to actuate
the drawer 58m between its retracted or closed and open or extended
positions. The rack 118, of course, need only extend over the rear
half of the lower carriage arm 59m as shown.
There are a few other features needed in this embodiment not found
in the one previously described. The first, and most significant,
of these is carriage-supporting roller 120 journaled for rotation
on stub shaft 121 within slot 124 in the lower front corner of rail
20m. In the absence of friction roller 46 of the earlier version,
roller 120 is needed to support the underside of the carriage.
Since the inboard location of the crankshafts 72m removes a measure
of support for the outer ends of the rails and cradles movable
relative thereto that is provided by crankshaft 72 of the previous
embodiment, longitudinal stringers 122 are used as shown to replace
the latter.
The changes required in endwall 78 (FIG. 6) to accommodate the
relocated crankshafts 72m comprise nothing more than eliminating
centerpost 82 and relocating uprights 80 in side-by-side parallel
relation in the space formerly occupied by the latter. Actually,
one could connect the crank subassembly 76 onto a free end of stub
shaft 42m as it emerges from column 24 and eliminate the endframe
78 altogether if it were not for the problem of gaining access
thereto between the projecting ends of the load when the drawers
are closed.
The third version 10n of the unit is that shown in FIGS. 13-15 to
which reference will now be made has the same disadvantage as the
one shown in FIGS. 11 and 12, namely, it is more complicated and,
therefore, more expensive than the preferred embodiment of FIGS.
1-5. In some respects it is quite similar to the version shown in
FIGS. 11 and 12 in that the crankshaft 72n runs down the middle and
is journaled for rotation in central column 24 rather than being on
the outside faces of the rack. Cradle 22n is unchanged over the one
in FIGS. 11 12 and the only change in rail 20n is to relocate the
pinion opening 116 in the top-wall 66n thereof so that it is
longitudinally-aligned with the one in the companion rail of the
pair on the opposite side of the post. Here, a single crankshaft
22n journaled within sleeve 118 for both rotational and axially
slidable movement is used to selectively engage one or the other of
the pinion sets 114a or 114b by means of a clutch mechanism
generally indicated by reference numeral 120. Collars 122 attached
to each sleeve bracketing the pinions permit free relative rotation
thereof.
Now, by moving the crankshaft 72n inward axially (upwardly in FIG.
14) clutch 120a engages pinion 114a to drive the cradle attached to
the latter in either direction while clutch 120b disengages and
leaves pinion 114b inoperative. Actually, of course, there will be
a series of two or more pinions 114a connected to operate the
drawer on one side of the rack while a similar set 114b will
function independently of the first set to operate the drawer on
the opposite side.
Clutch mechanism 120 is intended as being merely illustrative of
but one of a number of two-way mechanical clutches capable of
selectively turning the pinion sets 114a or 114b in either
direction. As shown, the hub 124 of each pinion has a pair of
diametrically-positioned ears 126 projecting therefrom which
engage, upon relative shaft rotation, a corresponding pair of ears
128 carried by flanged collar 130 mounted on said shaft for
conjoint rotation therewith. While conceivably, the pinions 114a
and 114b could be moved in and out of direct engagement with the
racks 118, the chances of the pinion teeth and rack teeth all being
aligned for meshed engagement is rather remote, therefore,
mechanical clutches which will operate in spite of such
misalignment are preferred. The clutch ears are shaped to cam past
one another even when partially opposed and those that are not
right together need only a fraction of a turn before they engage
and form a driving connection.
Finally, with specific reference to FIG. 14, one type of
representative mechanism that can be used to both turn shaft 72n
and shift it axially has been shown and identified in a general way
by numeral 132. Shaft 72n is mounted for axially-slidable and
rotational movement in collar 134. An internally-threaded collar
136 projects inwardly toward the shaft in coaxial relation thereto
from plate 98m in which it is journaled. Collar 136 comprises the
hub of gear 100m that replaces the sprocket 100 of the FIG. 8
reducer. Crank 94 connects onto gear 104m which meshes with gear
100m and replaces sprocket 104 thus eliminating chain 106. A
U-joint 138 connects threaded stub shaft 140 to the projecting end
of shaft 72n and also threads through collar 136. By holding shaft
72 stationary and rotating the crank 94 in the proper direction,
the gear train will turn collar 136 and either pull out or push in
shaft 72n by means of axial movement of stub shaft 140 until the
selected set of clutches 120 and their pinions 114 are engaged,
whereupon, pin 142 in the collar 136 is slipped into one of two
axially-spaced openings 144 in the stub shaft to lock these
elements together for further conjoint rotational movement in
either direction. The reducer 96m is maintained in fixed spaced
relation to the adjacent endwall 78m by spacers 146. Thus, a single
crankshaft 72n can be used to selectively actuate the drawers on
either side of the rack.
In the interests of simplicity of illustration, a unitary shaft 72n
has been shown, however, in actual practice a jointed shaft like
that previously described could, and probably would, be used to
lessen the alignment problems. The latter embodiment, while
eliminating half of the crankshafts, is the most complicated of the
three and, therefore, the least desirable.
* * * * *