U.S. patent application number 10/218398 was filed with the patent office on 2002-12-19 for push-back storage rack.
Invention is credited to Lewis, Lyman F..
Application Number | 20020190018 10/218398 |
Document ID | / |
Family ID | 23534890 |
Filed Date | 2002-12-19 |
United States Patent
Application |
20020190018 |
Kind Code |
A1 |
Lewis, Lyman F. |
December 19, 2002 |
Push-back storage rack
Abstract
A push-back storage rack comprises a frame defining at least one
storage bay having a depth sufficient to accommodate a plurality of
separate storage units; and a track-mounted carriage assembly
mounted in the bay. The carriage assembly comprises at least two
articulated carts connected together end-to-end for pivotal
movement about a transverse horizontal axis. The carts ride on a
track that has an upper track section, a lower track section, and
an arcuate front section that joins the upper and lower track
sections. The track guides the carts for movement between the front
and the rear of the bay on the upper track section and directs the
carts downwardly and then rearwardly on the lower track section in
an inverted position as the carts move forwardly at the front end
of the upper track section. The carts are thus stored underneath
the upper track section and are brought upwardly to the upper track
section as the carts are filled and moved rearwardly in the upper
track section.
Inventors: |
Lewis, Lyman F.; (Byron
Center, MI) |
Correspondence
Address: |
John A. Waters
Waters & Morse, P.C.
Ste. 400
125 Ottawa, S.E.
Grand Rapids
MI
49503
US
|
Family ID: |
23534890 |
Appl. No.: |
10/218398 |
Filed: |
August 14, 2002 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
10218398 |
Aug 14, 2002 |
|
|
|
09367408 |
Mar 14, 2000 |
|
|
|
6431378 |
|
|
|
|
09367408 |
Mar 14, 2000 |
|
|
|
08388634 |
Feb 14, 1995 |
|
|
|
6112915 |
|
|
|
|
Current U.S.
Class: |
211/151 ;
414/276; 414/286 |
Current CPC
Class: |
B65G 1/06 20130101; B65G
17/08 20130101 |
Class at
Publication: |
211/151 ;
414/276; 414/286 |
International
Class: |
A47F 005/00 |
Claims
I claim:
1. A push-back storage rack for storing individual storage units
comprising: a frame defining at least one storage bay having a
depth sufficient to accommodate a plurality of separate storage
units; and a track-mounted carriage assembly mounted in the bay,
the carriage assembly comprising at least two carts, each sized to
hold separate storage units, the carts being connected together
end-to-end for pivotal movement about a transverse horizontal axis,
the carts being movably supported and guided by the track, the
track being formed and mounted so as to guide the carts for
movement between a front and a rear of the bay on an upper track
section, and to direct at least a forwardmost cart downwardly and
then rearwardly in the bay in an inverted position on a lower track
section as the carts are moved forwardly at a front end of the
upper track section, the forwardmost cart thereafter being pulled
forwardly and then upwardly to the upper track section as rearmost
cart is pushed rearwardly on the upper track section.
2. A push-back storage rack according to claim 1 wherein the track
comprises opposed side sections on opposite sides of the bay and
including a generally straight upper section and an arcuate front
section that joins the upper and lower track sections.
3. A push-back storage rack according to claim 2 wherein the tracks
comprise horizontal support surfaces that support track contact
elements on the carts.
4. A push-back rack according to claim 3 wherein the track contact
elements are wheels and the track section comprises inwardly facing
C-shaped channel members in which the wheels fit.
5. A push-back rack according to claim 1 wherein at least the
forwardmost cart comprises a plurality of separate cart sections
connected together end-to-end for pivotal movement in a vertical
plane with respect to each other, each cart section being supported
by wheels at each end that ride on the track.
6. A push-back rack according to claim 1 wherein at least the
forwardmost cart comprises at least two sections pivotally
connected together for at least limited relative pivotal movement
in a vertical plane.
7. A push-back rack according to claim 6 wherein the sections of
said forwardmost cart are pivotal in one direction that facilitates
movement of the cart around an arcuate section of the track but
said sections are substantially not pivotal past a position of
horizontal alignment in the opposite pivotal direction.
8. A push-back rack according to claim 1 wherein the upper section
of track is inclined downwardly and forwardly toward the front of
the bay, such that gravity urges the carts and storage units
thereon to move toward the front of the bay on the upper track.
9. A push-back rack according to claim 1 wherein the carts comprise
frame members mounted on wheels at front and rear ends of the
frame, with the wheels riding on the tracks, adjacent carts being
mounted on common wheels positioned at junctions between the
carts.
10. A push-back rack according to claim 9 wherein the wheels are
mounted on axles, adjacent carts having wheel support fixtures at
corners of the carts, with the wheel support fixtures of adjacent
carts having axle openings therein that are alignable and are
connected together by insertion of the axles therethrough, the
connection between the axles and the wheel support fixtures
providing the means by which the carts are connected together.
11. A push-back rack according to claim 10 wherein at least one
cart comprises a plurality of separate, longitudinally aligned cart
sections, with the cart sections being connected together by wheels
in substantially the same manner as the separate carts.
12. A push-back rack according to claim 1 wherein each cart
comprises one or more transverse support beams having wheels
mounted at opposite ends thereof, the wheels riding on sections of
the track at each end of the beams, the beams being pivotally
interconnected for movement in a vertical plane by longitudinal
links that interconnect the beams.
Description
CROSS-REFERENCES TO RELATED APPLICATIONS
[0001] This is a continuation application of applicant's co-pending
U.S. patent application Ser. No. 09/367,408, filed Mar. 14, 2000,
which is a continuation-in-part application of co-pending U.S.
patent application Ser. No. 08/388,634, filed on Feb. 14, 1995,
both entitled PUSH-BACK STORAGE RACK, the disclosure of both
applications being incorporated herein by reference.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] Not Applicable.
BACKGROUND OF THE INVENTION
[0003] The present invention relates to push-back storage racks
used in warehousing and more particularly to a push-back storage
rack wherein moveable pallet carts are connected end-to-end and
wrap around and fit under an upper storage rack.
[0004] Warehouse storage racks typically comprise a frame structure
divided into rows and columns that define storage bays for
depositing storage units (e.g., pallets) of products to be stored.
In order to conserve space in a storage facility, storage bays are
sometimes more than one pallet deep, and moveable carriages, called
"push-back racks", are used to permit pallets to be moved to
rearward storage locations from a single loading station at the
front of the rack system. Most push-back racks employ overlying or
nesting platforms that fit one on top of the other at the front
storage compartment in the bay. As each platform is loaded and
pushed rearwardly, the next platform is made available for the next
pallet. Generally, the tracks on which the pallets are mounted are
inclined forwardly so that gravity causes the pallets to slide or
roll to the front of the storage bay. The track mechanisms and
carts required for this type of push-back rack can be complex and
expensive, and the system requires a different cart construction
for each storage location in the bay. Moreover, the maximum storage
unit depth of each bay is limited with stacking carts, and the
stacking carts introduce height limitations into the bay.
BRIEF SUMMARY OF THE INVENTION
[0005] In accordance with the present invention, a push-back
storage rack that provides a convenient and effective push-back
rack system, comprises a frame defining at least one storage bay
having a depth sufficient to accommodate a plurality of separate
storage units; a track-mounted carriage assembly is mounted in the
bay. The carriage assembly comprises at least two carts, each sized
to hold separate pallets or other storage units. The carts are
connected together end-to-end for pivotal movement about a
transverse horizontal axis. The track on which the carts ride has
an upper track section which guides the carts for movement between
the front and the rear of the bay. The track also includes a
forward section and a lower track section which direct the carts
downwardly and then rearwardly in the bay in an inverted position
as the carts move forwardly at the front end of the upper track
section. The carts are thus stored underneath the upper track
section and are brought upwardly to the upper track section for use
as the rearmost carts on the upper track section are filled and
moved rearwardly on the upper track section.
[0006] The preferred track of the present invention comprises
opposed C-shaped track members at opposite sides of the storage
bay, with the forward portion of the track section comprising an
arcuate section that connects the upper and lower track sections.
Other track constructions are possible.
[0007] The storage carts are wheeled carts that ride in the track,
with each wheeled cart preferably comprising a plurality of
separate wheeled cart sections connected together for pivotal
movement about a horizontal transverse axis. Desirably, the
individual cart sections also are articulated at an intermediate
longitudinal point to provide even further bending ability for the
cart sections.
[0008] The cart sections form a flat, stable platform for
supporting pallets on the upper track section but bend easily
around the arcuate forward track section for storage in an inverted
position in an out-of-the-way location underneath the upper track
section.
[0009] The individual carts are connected together by a connecting
mechanism that includes the axle for the wheels. The wheels are
mounted on axles that fit through aligned sleeves that are
connected to adjacent cart sections, thus permitting rotation of
the wheels as well as pivotal movement of the carts with respect to
each other.
[0010] The present invention provides a compact and cost effective
push-back rack system with interchangeable components, no stacking
cart height limitations, and virtually unlimited bay depth.
[0011] These and other features, objects, and benefits of the
invention will be recognized by one having ordinary skill in the
art, from the specification, the claims, and the drawing
figures.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING
[0012] FIG. 1 is a side elevational view of a push-back rack system
in accordance with the present invention.
[0013] FIG. 2 is a fragmentary perspective view showing a forward
comer of the track and cart system of the present invention.
[0014] FIG. 3 is a front elevational view of the present invention,
showing a pallet storage unit positioned on one of the carts of the
present invention.
[0015] FIG. 4 is a front elevational view similar to FIG. 3,
wherein a final pallet rests on the rails of the track system.
[0016] FIG. 5 is a perspective view showing the wheeled carts of
the present invention.
[0017] FIG. 6 is a plan view of one cart section of the present
invention.
[0018] FIG. 7 is an exploded perspective view showing the manner in
which two carts or two cart sections are connected together.
[0019] FIG. 8 is a fragmentary sectional view taken along lines 8-8
of FIG. 2, showing the manner in which two carts or cart sections
are connected together.
[0020] FIG. 9 is a fragmentary plan view showing the cart
connection mechanism of FIG. 7 in an assembled condition.
[0021] FIG. 10 is a fragmentary side elevational view of an
intermediate portion of a cart section, showing the articulated
side rails of the cart section.
[0022] FIG. 11 is a fragmentary front sectional view showing a
transverse alignment wheel on the cart riding in the track.
[0023] FIG. 12 is a fragmentary front sectional view showing an
alternative embodiment of a transverse alignment wheel for
maintaining proper transverse position of the carts.
[0024] FIG. 13 is a perspective view of an alternative embodiment
of the cart system of the present invention.
[0025] FIG. 14 is a plan view of the cart system of FIG. 13.
[0026] FIG. 15 is a side elevational view of a portion of the cart
system of FIG. 13, showing the wheels of the cart system riding in
a section of track.
[0027] FIG. 16 is a sectional view taken along line 16-16 of FIG.
15.
[0028] FIGS. 17A-17D are schematic drawings showing the manner in
which the present invention is used for loading multiple pallets in
a storage bay.
[0029] FIG. 18 is an alternative embodiment showing the use of a
separate pallet loading station at the front of the push-back rack
system of the present invention.
[0030] FIG. 19 is the view of FIG. 16 in mirror image and showing
an alternative wheel, arrangement.
[0031] FIG. 20 as a top plan view of a modular rack track middle
section.
[0032] FIG. 21 is an end elevational view along section line
XXI-XXI of FIG. 20.
[0033] FIG. 22 it is a side elevational view along section line
XXII-XXII of FIG. 20.
[0034] FIG. 23 is the view of FIG. 20, showing a strengthened
modular rack track end section.
[0035] FIG. 24 is an end elevational view along section line
XXIV-XXIV of FIG. 23.
[0036] FIG. 25 it is a side elevational view along section line
XXV-XXV of FIG. 23.
[0037] FIG. 26 is the view of FIG. 13, showing an alternative
positioning of the cart section links.
[0038] FIG. 27 is the view of FIG. 15, showing the alternative
positioning of the cart section links of FIG. 26.
[0039] FIG. 28 is a front elevational view of a front guard.
[0040] FIG. 29 is a top plan view thereof.
[0041] FIG. 30 is a right end elevational view thereof.
[0042] FIG. 31 is a fragmentary, side elevational view of a storage
rack, showing installation of a modular front curve section into a
storage bay.
[0043] FIG. 32 is the view of FIG. 30, showing the modular front
curve section in final position.
[0044] FIG. 33 is a fragmentary, side elevational view of a storage
rack, showing installation of a modular middle section into a
storage bay.
[0045] FIG. 34 is the view of FIG. 33, showing the modular middle
section in final position.
[0046] FIG. 35 is the view of FIG. 33, showing installation of a
modular end section into the storage bay.
[0047] FIG. 36 is the view of FIG. 35, showing the modular end
section in final position.
[0048] FIG. 37 is the view of FIG. 36, showing connection of the
modular sections.
[0049] FIG. 38 is the view of FIG. 36, showing installation of the
bottom stop assembly.
[0050] FIG. 39 is a side elevational view of a back top stop
bracket.
[0051] FIG. 40 is a front elevational view thereof.
[0052] FIG. 41 is a top plan view of a bottom stop assembly.
[0053] FIG. 42 is a side elevational view thereof.
[0054] FIG. 43 is an end elevational view thereof.
[0055] FIG. 44 is the fragmentary side elevational view detail XLIV
of FIG. 38, showing the bottom stop assembly installed.
DETAILED DESCRIPTION OF THE INVENTION
[0056] Referring now to the drawings, an exemplary warehousing
storage rack system 10, shown in FIG. 1, comprises a frame 12
consisting of spaced vertical columns 14 and horizontal beams 16
that define a series of vertically and horizontally spaced storage
bays 18. A single storage bay 18 is shown in FIG. 1, with the
storage bay comprising a front section 18A, a middle section 18B,
and a rear section 18C. Each storage bay section is positioned one
behind the other and is sized to accommodate a standard size of
storage unit. The storage unit is commonly a pallet 19, which is
loaded in the storage bay by a forklift truck 20, supports products
or goods 22, and is generally known by one having ordinary skill in
the art. A typical pallet is about forty inches (1016 mm) wide,
about forty-eight inches (1219 mm) long, and about five inches (127
mm) tall.
[0057] A track 24 extends from a front to a rear of the frame 12,
with the track having an upper section 26, a lower section 28, and
a curved or arcuate front section 30 that connects the upper and
lower sections of the track. A carriage mechanism consists of a
plurality of wheeled carts 32 that are mounted end-to-end on the
track 24, with each cart being subdivided into separate wheeled
cart sections 34.
[0058] Referring to FIGS. 2 and 3, track 24 comprises separate
track sections positioned at opposing sides of storage bay 18, with
the tracks being supported on the columns 14 and separated from the
columns by an about three inch (76 mm) square beam 16. Each track
24 comprises an inwardly facing C-shaped channel member 40 that has
opposing, upper and lower flanges 36 desirably spaced about 3-1/8
inches (79 mm) apart by a web portion. Carts 32 are provided with
wheels 38 at the four corners thereof, with the wheels extending
outwardly from the sides of the carts and riding in the channels 40
of the track 24.
[0059] The manner in which the carts 32 are constructed are shown
in FIGS. 5-12. In the illustrated embodiment, each cart 32
comprises four cart sections 34, with each cart section comprising
a rectangular frame that may be formed of about 2.times.2.times.1/8
inch (51.times.51.times.3 mm) angle iron, or the like, and that has
opposing side rails 42, a rear member 44, and a front member 45.
Side rails 42 may preferably be articulated, as shown in FIG. 10. A
front side rail section 46 is pivotally connected to a rear side
rail section 48 by means of a rivet or pivot pin 50. Pivot pin 50
extends outwardly from the side of the cart and has a wheel 58
rotatably mounted thereon. The wheel 58 may be a conventional,
steel roller skate wheel as is commonly known. The wheel 58 engages
the curved arcuate portion 30 of the track 24 and provides a low
friction interface between the cart section 34 and the track. More
preferably, the pivot pin 50 is provided at its end with a ball
caster 56 (FIG. 19) to run along the web portion of the channel 40
and guide the cart section 34, as will be understood by one having
ordinary skill in the art.
[0060] A top edge 49 (FIG. 10) of section 46 is recessed so that a
forward edge of the side wall constitutes a flange 52 that overlaps
the adjoining edge of side rail section 48. By constructing the
side rails 42 in this manner, they articulate downward, as shown in
phantom in FIG. 10, to allow the cart sections to "bend" when they
roll around the arcuate front section 30 of the track 24. When the
cart sections 34 are positioned in a horizontal position on the
upper track 26, however, upper edge 49 on section 46 engages upper
edge 51 on section 48 to prevent side rail 46 from pivoting
upwardly with respect to side rail 48, beyond the horizontal
position shown in FIG. 10. This also prevents the cart 32 from
sagging under load when a storage unit, or pallet 19, is mounted on
the cart.
[0061] The articulating side rails 42 are an important feature of
the present invention because of the dimensions of the structure.
In the preferred practice of the present invention, the distance
between the upper and lower track sections 26 and 28, respectively,
is minimized and desirably is about 11.5 inches (292 mm). The
individual cart sections 34 are each about 11.25 inches (286 mm)
long. Thus, it is necessary to articulate each of the individual
cart sections 34 to facilitate the movement of the cart sections
around the curved front portion 30 of the track 24, while
minimizing the distance between the upper and lower track
sections.
[0062] The manner in which the carts 32 and individual cart
sections 34 are connected together is shown in FIGS. 6-9. Cart
sections 34 and carts 32 are all connected in the same manner. An
axle shaft 60, having a head 61 and a narrow outer end 64 of
reduced diameter, fits through a plurality of tubular axle fittings
68 that are mounted on one of the carts 32 and a tubular axle
fitting 68 mounted on another of the carts. Axle fittings 66 are
spaced apart sufficiently that tubular fitting 68 fit between them.
Axle shaft 60 fits through interior openings 70 in the axle
fittings 66, when the fittings 66 and 68 are placed into alignment
with each other. A spring C-clip or E-clip 72 fits in groove 74 in
the axle shaft and holds the shaft in the axle fittings. Wheels 38
fit on narrower shaft 64 and are held in place by a nut or pin or
the like 73 on the outer end of shaft 64. A grease fitting 76, such
as a zerk nipple, mounted on the end of axle shaft 60 may be
provided to supply grease through an interior opening 78 to grease
outlets 80 and lubricate the axle shaft. The respective axle
fittings are welded to the carriages.
[0063] The axle fixtures forming the hinge of the present invention
desirably have a one inch (25 mm) outside diameter, a {fraction
(9/16)} inch (14 mm) inside diameter, and are 1/2 inch (13 mm)
long. The axle is a greasable axle 1/2 inch (13 mm) in diameter and
3-1/2 inches (89 mm) in length. The wheels preferably are 1-1/2
inches (38 mm) wide and 3 inches (76 mm) in diameter and may be
formed of phenolic resin or may be a metal wheel with bearings
(sometimes referred to as a skate wheel).
[0064] Transverse movement of the carts from a side-to-side
direction may be restricted by special transverse alignment wheels
of the type shown in FIGS. 11 or 12. As shown in FIG. 11, wheel 82
is conical and tapered slightly inward as it extends outward, so it
fits easily into track 24. The wheel desirably has a diameter of
about 3 to 23/4 inches (about 76 to 70 mm) and a taper of about
7-9E. The wheel also has a flange 84 extending radially greater
than the distance between the upper and lower surfaces of the track
24 (preferably the flange diameter is about 31/2 inches [89 mm]),
providing an inward limit that the wheel may extend into the track.
This restricts lateral movement of the cart 32. Desirably, the axle
86 of the wheel is threaded and is received in a threaded opening
90 in the cart. The lateral position of the alignment wheel thus
may be adjusted.
[0065] Another embodiment of an alignment device is shown in FIG.
12. An angle fixture 92 is mounted to the side of the cart section
with a horizontal wheel 93 mounted on a vertical axle 94 on flange
92. The wheel 93 engages the outer wall or web 96 of channel 40 and
constrains lateral movement of the cart section 34.
[0066] Another embodiment of the cart of the present invention is
shown in FIG. 13. Cart 100 comprises a plurality of longitudinally
spaced C-shaped cross beams 102, which are mounted to plates 104 at
each end thereof. Plates 104 have wheels 106 mounted thereon. Links
108 interconnect the adjacent wheels on each cross beam. Links 108
permit relative pivotal movement of the respective cross beams. The
same type of lateral alignment mechanism described above and shown
in FIGS. 11 and 12 can be employed with this embodiment of the
invention.
[0067] A modified embodiment of the present invention is shown in
FIG. 18. In FIG. 18, the push-back rack structure 110, shown in the
right hand portion of the figure, is substantially the same as the
rack structure described above, with the exception that an
additional storage compartment is provided in each bay, each bay
being four storage units deep. To accommodate four storage units,
it is necessary that the carriage or cart train be three carts
long. After the three carts are moved to the rear, a final pallet
can be placed on the rails themselves, as shown in FIG. 4.
[0068] An additional feature of the embodiment of FIG. 18 is that
an additional rack section 112 is positioned at the front of the
rack and is provided with a series of rollers 114. This makes it
possible to load a pallet 116 on section 112 and thereafter push
the pallet onto the roll back rack. With the extra section 112 at
the front of the rack, this rack can store pallets in a single bay
to a depth of five pallets. Also as shown in the FIG. 18
embodiment, storage bays can be positioned one above the other to
any desired height.
[0069] While storage mechanisms employing two and three cart units
are shown in the present invention, an advantage of the present
system is that almost any number of carts can be employed in the
rack system.
[0070] The operation of the present invention is shown in FIG.
17A-D for an exemplary system using a bay that is three units deep.
In FIG. 17A, a pallet 19A is placed on cart 32A. A stop plate 120
(shown in FIGS. 2, 3 and 4) prevents the loaded pallet from rolling
under the influence of gravity out through the open end of the bay
after the forklift truck has been removed. Stop plate is a right
angle plate spaced about one inch above the carriage assembly. The
stop plate is about three inches high and has a three inch long
flange attached to column A and a 4-1/2 to 7 inch long stop flange
that extends over the track and into the path of the pallet.
[0071] As shown in FIG. 17B, when pallet 19B is pressed against
pallet 19A, pallet 19A rolls along with cart 32A to section 18B of
the storage rack bay. Similarly, as shown in FIG. 17C, when pallet
19C is pushed against pallet 19B, all of the pallets slide inwardly
one station further, so that (as shown in FIG. 17D) pallet 19A and
cart 32A are in section 18C of the bay. Similarly, pallet 19C and
cart 32B are in section 1 8B of the bay. Finally, pallet 19C sits
on the rail 24 in section 1 8A of the bay. Stop 120 prevents any of
the pallets from sliding outwardly unless lifted over the stop. The
reverse operation is accomplished in removing the pallets from the
rack, with gravity causing the cart to roll forwardly as each
pallet at the front of the rack is removed. Desirably, the track is
inclined at an inclination of one inch (25.4 mm) per four feet
(1219 mm) of rack length.
[0072] In the present invention, a simple C-channel track can be
used to support and guide the carts. This track can be formed in
uniform sections of 8 feet in length or so, with each section being
cut to size and bolted together as desired. Thus, only straight
sections of uniform track and the curved front portion of the track
need to be prefabricated.
[0073] In another embodiment of the invention, the push back
storage rack system may be configured as a modular system having a
front curve section 202, an end section 204, and as many middle
sections 206 as are required or desired. This embodiment not only
includes the modular configuration, it also incorporates a
relocation of the cart interconnecting links 108 to an inboard
position on the wheel axle 109 (FIGS. 19, 26, and 27).
[0074] The modular middle section 206 is assembled with opposing,
mirror image track assemblies 210 that have upper and lower track
sections 26 and 28, respectively, spaced apart, about the width of
the carts 32, and facing one another. A set of cart sections 34 are
positioned in and extend along the length of the upper track
section 26. The upper and lower track sections 26 and 28,
respectively, are preassembled with generally vertical structural
brackets 212 that hold the upper and lower track sections generally
parallel with one another. The vertical structural brackets 212 may
also have an inwardly extending flange member 214 that is slidably
connected, preferably with the rearward vertical structural
bracket, to fasten the modular rack section to a structural cross
beam 16 of the rack system frame 12, as will be understood by one
having ordinary skill in the art. Most preferably, the upper and
lower track sections 26 and 28, respectively, are a generally
G-shaped modification (FIG. 19) of the C-channel 40, discussed
further above, with an upward turned flange 220 on the lower leg
222. The flange 220 is useful to maintain the wheels 106 in the
channel and minimize any potential for the wheels to drift out of
the track channel.
[0075] The modular front curve section 202 is substantially similar
to the modular middle section 206, with mirror image track
assemblies 210 having upper and lower track sections 26 and 28,
respectively, a set of cart sections 34 positioned in and extending
along the upper track section, the upper and lower track sections
been assembled with a generally vertical structural brackets 212,
and the upper and lower track sections being G-shaped. The modular
front curve section 202 is, however, distinguished from the modular
middle section 206 by a curve portion 230 that extends from the
upper track section 26 to the lower track section 28, connecting
the upper and lower track sections for transfer of the cart
sections 34 between them. The curve portion 230 also has a forward
mounting plate to connect with the first horizontal load beam 16 or
vertical column 14 of the rack frame 12.
[0076] As to the modular end section 204, it is also substantially
similar to the modular middle section 206, with the same track
assemblies 210 and the generally G-shaped track sections. The
modular end section 204 is different from the modular middle
section 206, however, because of the use of a single cart 240 that
is positioned in and extends along the upper track section, rather
than a set of cart sections 34 as is used for each of the modular
front curve section 230 and the modular middle section 206. The
single cart 240 of the modular end section generally conforms to
the storage unit, pallet 19, in width and length. The single cart
240 of the modular end section 204 is advantageous in positioning
the push back storage rack system in an empty condition. That is,
in addition to the stops and guards, the single cart 240 will not
traverse around the curve portion 230 of the modular front curve
section 202, and will remain in position in the upper track section
26 of the modular front curve section, standing ready to receive a
pallet for storage.
[0077] In use, the modular push back storage rack system is
installed into a storage rack frame 12 with the modular front curve
section 202 being installed first (FIGS. 31 and 32). The modular
section 202 is positioned in a front or first portion 18A of a
storage bay 18 and the second load beam 16 of the rack frame 12 is
positioned between the back ends of the upper and lower track
sections 26 and 28, respectively. The modular front curve section
202 is slid reward so the front of the section and the mounting
plate 232 clears the rack frame 12 and is positioned for secure
attachment to the first or front load beam 16 at the front of the
rack frame 12. With the modular front curve section 202 so
positioned, left hand 242, center 244, and right hand 246 stops and
a front guard 248 (FIGS. 28-30) are mounted at the front load beam
16 for holding a pallet 19, for example, in a ready positioned for
retrieval or push back by another pallet that is added to the
storage bay 18.
[0078] The modular middle section 206 is similarly positioned in a
second portion 18B of the rack frame 12, behind of the modular
front curve section 202, by positioning the next, or third load
beam 16 between the back ends of the upper and lower track sections
26 and 28, respectively, and positioning the front of the modular
middle section in coupling engagement with the back of the modular
front curve section (FIGS. 33 and 34). The modular front curve and
middle sections 202 and 206, respectively, are interconnected with
eight 1/4-20 screws. As many of the modular middle sections 206 as
are desired are sequentially connected, as just described, up to
the last portion of the storage bay 18. A modular end section 204
is then installed in the last portion of the storage bay 18, in
substantially the same manner that each of the modular middle
sections 206 is installed (FIGS. 35-36). Again, the only
significant, distinguishing feature of the modular end section 204
as compared to the modular middle section 206 is the use of a
single cart 240 that extends along the length of the section 204 as
opposed to a set of cart sections 34 that extend along the length
of the section.
[0079] With each of the modular curve, middle, and end sections
202, 206, and 204, respectively, installed in the rack frame 12,
adjoining carts 32 or 240 are interconnected by use of an access
hole 250 (FIG. 37) that is positioned about mid-way along the upper
track section 26 of the modular front curve section 204. The last
wheel 106 of a cart 32 is aligned with the access hole 250 so a
link 108 (FIGS. 19 and 37) that extends forward from the next cart
32 or 240 may engage the axle 109 of that last wheel 106 and be
secured with a nut 252, preferably a cap nut or lock nut, by access
to the wheel axle through the access hole 250 and to the nut 252
under the cart 32 (see FIG. 19).
[0080] In addition to the stops and guards described above, a
bottom stop (FIGS. 38 and 41-44) may also be installed on the lower
track section 28 at a location one pallet position in or forward
from the rear of the unit. The bottom stop will, therefore, be
positioned near the back end of the last modular middle section
206, before the modular end section 204. Also, a back, top stop
bracket (FIGS. 38-40) may be installed at the back of the upper
track section 26 of the modular end section 204 to keep the carts
32 and 240 from being pushed out the back of the upper track
section 26.
[0081] Optionally, a center track 260 (FIGS. 23-25) may be
installed between the upper track sections 26 of the modular front
curve, modular middle, and modular end sections 202, 206, and 204,
respectively, for rack storage systems that are required to carry
extra heavy loads. In the optional, extra heavy load installation,
each cart 32 and the singular cart 240 of the modular end section
204 will also be provided with center support wheels 106 to engage
and run on the center track 260.
[0082] It should be understood that the foregoing is merely
exemplary of the preferred practice of the present invention and
that various changes and modifications may be made in the
arrangements and details of construction of the embodiments
disclosed herein without departing from the spirit and scope of the
present invention, as defined in the appended claims.
* * * * *