U.S. patent application number 14/147420 was filed with the patent office on 2015-07-09 for pivotable pack frame apparatus.
This patent application is currently assigned to Easton Technical Products, Inc.. The applicant listed for this patent is Easton Technical Products, Inc.. Invention is credited to John A. Bercaw, Steven Paul Horvath.
Application Number | 20150189974 14/147420 |
Document ID | / |
Family ID | 53494297 |
Filed Date | 2015-07-09 |
United States Patent
Application |
20150189974 |
Kind Code |
A1 |
Bercaw; John A. ; et
al. |
July 9, 2015 |
PIVOTABLE PACK FRAME APPARATUS
Abstract
A pack frame apparatus having first and second frame portions
configured to be secured to a backpack, wherein the first and
second frame portions provide structural rigidity to the backpack
when secured to the backpack. The first frame portion is configured
to be secured to shoulder straps of the backpack, and the second
frame portion is configured to be secured adjacent to a waist strap
of the backpack. A joint joins the first and second frame portions
to allow relative pivotal movement around a first axis and to allow
resilient relative pivotal movement around a second axis.
Inventors: |
Bercaw; John A.; (Salt Lake
City, UT) ; Horvath; Steven Paul; (Ontario,
CA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Easton Technical Products, Inc. |
Salt Lake City |
UT |
US |
|
|
Assignee: |
Easton Technical Products,
Inc.
Salt Lake City
UT
|
Family ID: |
53494297 |
Appl. No.: |
14/147420 |
Filed: |
January 3, 2014 |
Current U.S.
Class: |
224/633 ;
224/261 |
Current CPC
Class: |
A45F 3/04 20130101; A45F
2003/045 20130101; A45F 3/08 20130101 |
International
Class: |
A45F 3/10 20060101
A45F003/10; A45F 3/04 20060101 A45F003/04 |
Claims
1. A pack frame apparatus, comprising: a first frame portion
configured to be secured to a backpack, the first frame portion
providing structural rigidity to the backpack when secured to the
backpack, the first frame portion being configured to be secured to
shoulder straps of the backpack; a second frame portion configured
to be secured to the backpack, the second frame portion providing
structural rigidity to the backpack when secured to the backpack,
the second frame portion being configured to be secured adjacent to
a waist strap of the backpack; a joint joining the first and second
frame portions to allow relative pivotal movement of the first and
second frame portions around a first axis and to allow resilient
relative pivotal movement around a second axis.
2. The pack frame apparatus of claim 1, wherein the first axis is
oriented about normal to a coronal plane.
3. The pack frame apparatus of claim 2, wherein the second axis is
about parallel to the coronal plane.
4. The pack frame apparatus of claim 1, wherein the joint comprises
a resilient member positioned between the first and second frame
portions.
5. The pack frame apparatus of claim 4, wherein the joint further
comprises a rigid member, wherein the resilient member is
positioned between the rigid member and at least one of the first
and second frame portions.
6. The pack frame apparatus of claim 4, wherein the joint further
comprises a rigid member positioned between the resilient member
and at least one of the first and second frame portions.
7. The pack frame apparatus of claim 4, wherein the joint is biased
to orient the first and second frame portions in a default relative
orientation due to resilience of the resilient member.
8. The pack frame apparatus of claim 4, wherein the resilient
member is configured as a shock absorber between the first and
second frame portions.
9. The pack frame apparatus of claim 1, wherein the joint is
removably attached to the first and second frame portions.
10. The pack frame apparatus of claim 1, wherein the joint is
biased to orient the first and second frame portions in a default
relative orientation.
11. The pack frame apparatus of claim 10, wherein the joint has
uneven thickness around the first axis.
12. The pack frame apparatus of claim 10, wherein the joint has
even thickness around the first axis.
13. The pack frame apparatus of claim 1, wherein at least two
portions of the joint interlock in a default relative orientation
of the first and second frame portions.
14. The pack frame apparatus of claim 1, wherein the joint
interlocks with at least one of the first and second frame portions
in a default relative orientation of the first and second frame
portions.
15. The pack frame apparatus of claim 1, wherein the joint is
configured to selectively tighten and loosen the joining of the
first and second frame portions.
16. The pack frame apparatus of claim 1, wherein the joint is
further configured to allow resilient relative pivotal movement of
the first and second frame portions around a third axis.
17. A flexible pack, comprising: an upper frame configured to be
positioned in the pack adjacent to a torso portion of a user above
the user's waist; a pair of shoulder straps configured to attach to
the upper frame and wrap around the shoulders of the user; a lower
frame configured to be positioned in the pack adjacent to a torso
portion of a user adjacent to the user's waist; a waist strap
configured to attach to the backpack adjacent to the lower frame; a
storage pouch portion attached to at least one of the upper and
lower plates, the storage pouch portion adapted to removably hold
equipment; a flexible joint joining the upper and lower frames, the
flexible joint allowing relative motion of the upper and lower
frames in a pivot direction and allowing resilient relative motion
in a torsional direction.
18. The flexible backpack of claim 17, wherein the flexible joint
is positioned in the backpack relative to a lumbar area of the
user.
19. The flexible backpack of claim 17, wherein the flexible joint
comprises an elastic portion positioned between the upper and lower
frames.
20. The flexible backpack of claim 19, wherein the flexible joint
comprises a rigid portion positioned between at least one of the
upper and lower frames and the elastic portion.
21. The flexible backpack of claim 19, wherein the flexible joint
is selectively tightenable to adjust a range of relative motion of
the upper and lower frames in at least the torsional direction.
22. The flexible backpack of claim 17, wherein the flexible joint
permits relative pivotal motion of the upper and lower frames of at
least about 45 degrees in the pivot direction and permits relative
torsional motion of at least about 20 degrees in the torsional
direction.
23. The flexible backpack of claim 17, wherein the flexible joint
is biased to orient the upper and lower frames in an upright
position.
24. The flexible backpack of claim 17, wherein the upper and lower
frames are shaped to conform to a rear portion of a human body.
25. A method of providing a pack frame apparatus, the method
comprising: providing a first plate and a second plate, the first
and second plates adapted to provide structural support to a pack
frame, the first plate being positioned for support of an upper
back portion of a user through attachment to a shoulder strap, the
second plate being positioned for support of a lower back portion
of the user through attachment to a waist strap; pivotally joining
the first plate with the second plate, the first and second plates
being relatively rotatable in a first direction, the first and
second plates being resiliently relatively rotatable in a second
direction.
26. The method of claim 25, wherein joining the first plate with
the second plate comprises: inserting a resilient member between
the first and second plates; joining the first and second plates
around the resilient member for pivotal movement along the first
direction.
27. The method of claim 25, further comprising: attaching the
joined first and second plates with a backpack having shoulder
straps and a storage compartment.
28. The method of claim 25, further comprising: adjusting the range
of relative rotation of the first and second plates in at least the
second direction by tightening or loosening a member joining the
first and second plates.
29. The method of claim 25, wherein the relative rotation between
the first and second plates is biased to assume a default position
in at least one of the first and second directions.
Description
BACKGROUND
[0001] The following relates generally to support systems for packs
and specifically to a multi-piece pivotable support frame for a
backpack.
[0002] Historically, external frame pack designs have been made
from tubes made of aluminum or another light, rigid material. These
packs are good for bearing heavy loads and directing the loads to
the hips of the wearer. Pack frames for external frame packs are
typically spaced away from the wearer's body due to the rigid
shapes used. Skiing, hiking, running, and other dynamic activities
may be more difficult using a non-conforming pack due to swaying of
the pack (even when strapped to the wearer) and the weight of the
pack being spaced from the wearer's body. The spaced center of
gravity of the pack from the wearer's body may throw the wearer
off-balance or cause unnecessary fatigue by its swaying and other
motion relative to the wearer's body.
[0003] More recently, internal frame packs have been implemented
which help to keep the load of the pack closer to the wearer's body
using contoured shapes. They are designed to hold less weight and
their contours may limit the range of motion of the wearer.
Internal frame packs are therefore designed to balance the
competing interests of weight-bearing capacity and rigidity of the
pack against the comfort and mobility of the wearer, but fail to
optimally address both needs at once.
[0004] Some pack frames comprise pivoting portions that attempt to
follow the wearer's body through movements, such as through
pivoting strap connections to a rigid frame. They fail to provide
sufficiently for flexion and extension of the user's spine. For
this and other reasons, these frames do not feel like a natural
extension of the wearer. Furthermore, adding joints between
portions of these pack frames tends to overly reduce rigidity and
causes wearers to have to exert more force to keep the pack
properly oriented on their backs.
SUMMARY
[0005] According to at least one embodiment, a pack frame apparatus
is disclosed. The pack frame apparatus may comprise a first frame
portion configured to be secured to a backpack and a second frame
portion configured to be secured to the backpack. These first and
second frame portions may provide structural rigidity to the
backpack when secured to the backpack. The first frame portion may
be configured to be secured to shoulder straps of the backpack, and
the second frame portion may be configured to be secured adjacent
to a waist strap of the backpack. The apparatus may also include a
joint joining the first and second frame portions to allow relative
pivotal movement of the first and second frame portions around a
first axis and to allow resilient relative pivotal movement around
a second axis.
[0006] The first axis may be oriented approximately normal to a
coronal plane, and the second axis may be approximately parallel to
the coronal plane.
[0007] The joint may comprise a resilient member positioned between
the first and second frame portions. The joint may further comprise
a rigid member, wherein the resilient member is positioned between
the rigid member and at least one of the first and second frame
portions. In some embodiments, the joint may further comprise a
rigid member positioned between the resilient member and at least
one of the first and second frame portions. In yet further
embodiments, the joint may be biased to orient the first and second
frame portions in a default relative orientation due to resilience
of the resilient member.
[0008] The joint may be removably attached to the first and second
frame portions. The joint may also be biased to orient the first
and second frame portions to a default relative orientation. The
joint may have uneven thickness around the first axis. At least two
portions of the joint may interlock in a default relative
orientation of the first and second frame portions. The joint may
interlock with at least one of the first and second frame portions
in a default relative orientation of the first and second frame
portions, and the joint may be configured to selectively tighten
and loosen the joining of the first and second frame portions.
[0009] In another exemplary embodiment, a flexible pack is
provided, comprising an upper frame configured to be positioned in
the pack adjacent to a torso portion of a user above the user's
waist; a pair of shoulder straps configured to attach to the upper
frame and wrap around the shoulders of the user; a lower frame
configured to be positioned in the pack adjacent to a torso portion
of a user adjacent to the user's waist; a waist strap configured to
attach to the backpack adjacent to the lower frame; a storage pouch
portion attached to at least one of the upper and lower plates
which is adapted to removably hold equipment; and a flexible joint
joining the upper and lower frames, the flexible joint allowing
relative motion of the upper and lower frames in a pivot direction
and allowing resilient relative motion in a torsional
direction.
[0010] The flexible joint may be positioned in the backpack
relative or near to a lumbar area of the user. The flexible joint
may comprise an elastic portion positioned between the upper and
lower frames. The flexible joint may comprise a rigid portion
positioned between at least one of the upper and lower frames and
the elastic portion. The flexible joint may be selectively
tightenable to adjust a range of relative motion of the upper and
lower frames in at least the torsional direction. The flexible
joint may permit relative pivotal motion of the upper and lower
frames of at least about 45 degrees in the pivot direction and may
permit relative torsional motion of at least about 20 degrees in
the torsional direction. The flexible joint may be biased to orient
the upper and lower frames in an upright position.
[0011] In some embodiments, the upper and lower frames may be
shaped to conform to a rear portion of a human body.
[0012] In another exemplary embodiment, a method of providing a
pack frame apparatus is disclosed, with the method comprising
providing a first plate and a second plate, the plates being
adapted to provide structural support to a pack frame, the first
plate being positioned for support of an upper back portion of a
user through attachment to a shoulder strap, the second plate being
positioned for support of a lower back portion of the user through
attachment to a waist strap; and pivotally joining the first plate
with the second plate, the first and second plates being relatively
rotatable in a first direction and being resiliently relatively
rotatable in a second direction.
[0013] Joining the first plate with the second plate may comprise
inserting a resilient member between the first and second plates
and joining the first and second plates around the resilient member
for pivotal movement along the first direction.
[0014] The method may also comprise attaching the joined first and
second plates with a backpack having shoulder straps and a bag,
pouch, or other type of storage compartment. The method may also
comprise adjusting the range of relative rotation of the first and
second plates in at least the second direction by tightening or
loosening a member joining the first and second plates.
[0015] In some embodiments, the relative rotation between the first
and second plates may be biased to assume a default position in at
least one of the first and second directions.
[0016] The foregoing and other features, utilities and advantages
of the invention will be apparent from the following more
particular description of a preferred embodiment of the invention
as illustrated in the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] The accompanying drawings and figures illustrate a number of
exemplary embodiments and are part of the specification. Together
with the present description, these drawings demonstrate and
explain various principles of this disclosure. A further
understanding of the nature and advantages of the present invention
may be realized by reference to the following drawings. In the
appended figures, similar components or features may have the same
reference label.
[0018] FIG. 1A illustrates a rear perspective view of a pack frame
according to an embodiment of the present disclosure.
[0019] FIG. 1B illustrates the pack frame shown in FIG. 1A relative
to the remainder of an exemplary backpack.
[0020] FIG. 2A is a rear plan view of the pack frame of FIG.
1A.
[0021] FIG. 2B is a front plan view of the pack frame of FIG.
1A.
[0022] FIG. 2C is a left side plan view of the pack frame of FIG.
1A next to a profile of a wearer.
[0023] FIG. 3A is an exploded rear perspective view of a pack frame
joint according to an embodiment of the present disclosure.
[0024] FIG. 3B is an exploded front perspective view of the joint
of FIG. 3A.
[0025] FIG. 3C is an exploded bottom view of the joint of FIG.
3A.
[0026] FIG. 3D is an exploded side view of the joint of FIG.
3A.
[0027] FIG. 4A is a bottom section view of the joint of FIG. 2B
through section lines 4A in FIG. 2B.
[0028] FIG. 4B is a side section view of the joint of FIG. 2B
through section lines 4B in FIG. 2B.
[0029] FIG. 5A is an illustration of an upright user positioned
relative to a pack frame apparatus according to the present
disclosure.
[0030] FIG. 5B is an illustration of a turning user positioned
relative to a pack frame apparatus according to the present
disclosure.
[0031] FIG. 5C is an illustration of a leaning user positioned
relative to a pack frame apparatus according to the present
disclosure.
[0032] While the embodiments described herein are susceptible to
various modifications and alternative forms, specific embodiments
have been shown by way of example in the drawings and will be
described in detail herein. However, the exemplary embodiments
described herein are not intended to be limited to the particular
forms disclosed. Rather, the instant disclosure covers all
modifications, equivalents, and alternatives falling within the
scope of the appended claims.
DETAILED DESCRIPTION
[0033] According to some embodiments of the present disclosure, a
pack frame apparatus is provided that provides rigidity to a pack
while following the natural movement of wearers and helping wearers
to bear loads in a normal orientation. Thus, these embodiments may
reduce fatigue, increase weight bearing capacity, and provide a
more natural and comfortable feel to wearers.
[0034] A pack frame apparatus may comprise two frame portions or
plates that are joined to each other by a joint that allows
relative pivotal movement of the frame portions around a first axis
and allows resilient relative pivotal movement around a second
axis. A first frame portion may be positioned adjacent to the upper
torso of wearers, and the second frame portion may be positioned
adjacent to the lower torso, near or below the waist. A joint
between the frame portions links them together while allowing them
to rotate relative to each other in multiple directions. For
example, the joint may connect the frame portions while allowing
relative pivotal movement around the first axis when wearers lean
laterally (i.e., left or right) while also allowing relative
movement of the frame portions when wearers exert torsional forces
on the plates (i.e., turning, left/right or up/down at the lower
back). See, e.g., FIGS. 5A-5C.
[0035] Thus, the pack frame apparatus can accommodate multiple
degrees of freedom at the back of the user. The joint may be
designed with a resilient portion that allows a limited range of
motion compared to a primary direction of pivotability of the
joint, thereby providing a limited amount of "give" to the frame
and increasing comfort, shock absorption, and adaptability of the
frame to active wearers. Because the range of motion afforded by
the resilient portion is limited, the flexibility of the joint does
not sacrifice an undue amount of rigidity and weight bearing
capacity.
[0036] In some embodiments, the joint may be adjustable, thereby
providing a varying degree of restriction to the relative movement
of the frame portions. By tightening or loosening the joint, the
frame portions may become more rigidly or flexibly attached to each
other. This may provide adaptability to the frame, where wearers
may choose the amount of rigidity desired for a particular task at
hand.
[0037] The joint may be designed to assist the user in orienting
the frame portions in one or more particular relative position. For
example, the joint may be designed with notches and grooves that
coincide with each other when the frame portions are vertically
aligned, and wearers must therefore overcome extra resistance to
reorient the frame portions by removing the notches from the
grooves as they turn in one or more direction. Other structures,
such as nubs and depressions, may alternatively be used. Similarly,
the joint may be configured with materials that resiliently bias
relatively rotated frame portions into a preferred default
position.
[0038] While reference herein is made to a frame for a backpack, it
will be appreciated that the scope of the disclosure may also
include frames for other devices and equipment worn on a moving
body (e.g., the human body), including, for example, rucksacks,
knapsacks, messenger bags, bookbags, hydration packs, fanny packs,
sling bags, duffel bags, satchels, parachutes, and other
cargo-carrying wearable vessels. Application of the principles and
elements of the present disclosure may find beneficial use in
various outdoor activities, including military, sports, travel, and
other industries. Elements of the present disclosure may be applied
in other body-conforming devices, such as body armor (e.g.,
security vests), sports equipment (e.g., protective body pads), and
harnesses.
[0039] The present description provides examples, and is not
limiting of the scope, applicability, or configuration set forth in
the claims. Thus, it will be understood that changes may be made in
the function and arrangement of elements discussed without
departing from the spirit and scope of the disclosure, and various
embodiments may omit, substitute, or add other procedures or
components as appropriate. For instance, the methods described may
be performed in an order different from that described, and various
steps may be added, omitted, or combined. Also, features described
with respect to certain embodiments may be combined in other
embodiments.
[0040] Turning now to the figures, FIG. 1 A illustrates a rear
perspective view of a pack frame 100 according to an embodiment of
the present disclosure. The pack frame 100 may include an upper
frame portion 102 and a lower frame portion 104 joined by a joint
106. The upper frame portion 102 may correspond to a portion of a
pack arranged to be adjacent to a wearer's upper torso, and the
lower frame portion 104 may correspond to the wearer's lower torso.
The joint 106 may be oriented to pivotably join the upper and lower
frame portions 102, 104 in or around the lumbar area of a wearer.
See also FIGS. 5A-5C.
[0041] As used herein, the "rear" of the pack frame 100 faces the
back of the wearer when worn, and the "front" of the pack frame 100
faces away from the wearer, such as toward attached backpack
compartments or other cargo space.
[0042] The upper and lower frame portions 102, 104 may comprise a
generally rigid, lightweight material. In some embodiments, the
frame portions 102, 104 may comprise a composite material, such as,
for example, carbon fiber or fiberglass. Plastics, metals, wood,
and combinations thereof may also be used for some or all of the
frame portions 102, 104, such as, for example, to provide
additional resilience or rigidity to sections of the frame portions
102, 104. The frame portions 102, 104 may be molded or otherwise
formed with contours providing flexibility and easier attachment of
backpack features to the frame portions 102, 104. In some
embodiments, the contours of the frame portions 102, 104 may be
shaped to direct cargo away from the surface of the wearer's body
or to take the shape of certain types of cargo. For example, upper
flanges 108 may be curved away from the wearer to facilitate
strapping the flanges 108 to a cylindrical element such as a
bedroll.
[0043] In some embodiments (not shown), the curvature of the frame
portions 102, 104 may generally correspond to a backside of a
human, with a lumbar portion (around joint 106) following the
lumbar area of a wearer, the upper frame portion 102 having an
upper end (near flanges 108 and shoulder area 114) that follows the
contours of the upper back of the wearer, and the lower frame
portion 104 extending from the joint 106 with a contoured area 118
following the lower back and gluteal region of the wearer's body.
In this configuration, the frame portions 102, 104 may fit more
closely to the wearer, bringing the center of gravity of the
backpack closer to the wearer's center of gravity. In other
configurations, portions of the frame portions 102, 104 may be
contoured toward the wearer while other portions curve away.
[0044] The upper frame portion 102 may comprise upper flanges 108.
These flanges 108 may be adapted to extend vertically higher than
the wearer's shoulders or shoulder blades. The upper flanges 108
may provide rigidity to the over-shoulder region of the pack while
also providing limited flexibility in that area due to the
thickness and materials used in their construction.
[0045] The perimeter of the upper frame portion 102 may comprise
attachment slots 110 configured to attach to a pack, e.g., pouches,
straps, and/or other backpack features. In some embodiments, the
attachment slots 110 may be configured on the upper frame portion
102 to allow wearers to change selectively the position of straps,
bags, pouches, cords, pads, cushions, and other features. The lower
frame portion 104 may also comprise attachment slots 110 (not
shown) to attach a waist strap, sleep roll, pouch, or other
features of a pack.
[0046] A surface of the upper frame portion 102 may comprise
generally horizontal strap slots 112, such as in the shoulder area
114 of the upper frame portion 102. The strap slots 112 may provide
an attachment point for shoulder straps that extend around the
wearer's shoulders. See FIG. 1B. Eight strap slots 112 are shown in
the figures, but more or less may be used. When using multiple
strap slots 112, the shoulder straps may be repositioned to
accommodate different wearer sizes or strap lengths. The strap
slots 112 may also provide additional flexibility and ventilation
to the shoulder area 114, thereby providing additional comfort to
wearers by permitting airflow and bending near their joints. Strap
slots 112 may also be used to decrease the weight of the pack frame
apparatus 100. In some embodiments, the strap slots 112 are covered
or obscured by bags or other enclosures, and thus may not provide
airflow. In some embodiments, the strap slots 112 may be used to
attach backpack elements and cushions, similar to the attachment
slots 110 described above. Strap slots 112 may also be positioned
on the upper pack frame 102 in a position other than the shoulder
area 114 where ventilation, flexibility, or attachment points are
desired. In some arrangements, the lower pack frame 104 may
comprise strap slots 112. Lower pack frame 104 strap slots 112 may
be used to attach the lower portion of a shoulder strap or to
attach waistband straps.
[0047] The lower pack frame 104 may comprise an opening 116 and a
contoured area 118. The opening 116 may reduce the weight and
increase flexibility of the pack frame apparatus 100. The opening
116 may also provide a relief opening for the lower back or sacral
areas of wearers by distributing weight of the pack to the sides of
the spinal column and toward the iliac crests of the pelvis. The
opening 116 may also be configured to receive a pad for this area
of wearer.
[0048] The contoured area 118 may provide a transition between the
portion of the lower pack frame 104 attached to joint 106 and the
bottom end of lower pack frame 104. The contoured area 118 may
facilitate easier attachment of curved bags and other cargo. In
some embodiments, the contoured area 118 may also follow the
natural curve of the lower back of a wearer to improve comfort and
decrease the amount of flexure of the lower pack frame 104 needed
to conform to the shape of the wearer's body.
[0049] FIG. 1B illustrates a pack frame 100 shown relative to the
remainder of an exemplary backpack. The pack frame 100 is attached
to the backpack. A main pack portion 120 may include one or more
pouch or load-carrying pockets and may be secured to extend
rearward from the upper pack frame 102, and a second pouch 122 and
one or more side pouch 124 may be adjacent to the lower pack frame
104. Shoulder straps 126 may extend from the upper pack frame 102
(e.g., from strap slots 112) and attach to another portion of the
upper pack frame 102 (e.g., at attachment slots 110), the lower
pack frame 104, or to pouches or other material on the backpack.
The shoulder straps 126 may be configured to wrap around the
shoulders and upper body of a wearer. Waist straps 128 may extend
from the lower end of the backpack, such as from an attachment to
the lower pack frame 104 or a lower portion of the upper pack frame
102. The waist straps 128 may be configured to connect to each
other after wrapping around the lower back, waist, or pelvic area
of a wearer, such as by a buckle. Additional and alternative
configurations of pouches, straps, cords, pads, and other backpack
elements will be apparent to those skilled in the art of backpack
design and having the benefit of the present disclosure.
[0050] FIGS. 2A-2C show alternate views of the pack frame 100 of
FIGS. 1A-1B. FIG. 2A is a rear plan view, FIG. 2B is a front plan
view, and FIG. 2C is a left side plan view. FIG. 2C also shows the
profile of an exemplary wearer next to the pack frame 100. As shown
in these figures, the upper pack frame 102 overlaps the lower pack
frame 104 in and around the region where the joint 106 is located.
In these embodiments, the lower pack frame 104 is positioned
forward relative to the upper pack frame 102 at the joint 106, but
in other embodiments, their relative positions may be reversed.
[0051] Positioning the upper pack frame 102 closer to the wearer
than the lower pack frame 104 may provide more contact between the
lower pack frame 104 and the cargo carried by the backpack, thereby
facilitating attachment of the cargo to the lower pack frame 104.
The joint 106 may also be easily adjustable, since the adjustment
cap 300 may face the wearer's body.
[0052] When their relative positions are reversed, positioning the
lower pack frame 104 closer to the wearer than the upper pack frame
102 may be beneficial in improving shock absorption capability of
the pack frame 100. When the pack frame 100 is worn, contact
between the lower pack frame 104 and the wearer may apply a
constant force against the lower pack frame 104 that may not be
present if the lower pack frame 104 is positioned behind the upper
pack frame 102 at the joint 106. Thus, adjustments to the position
or movement of the wearer may more directly and granularly be
responded to by relative rotation of the upper and lower pack
frames 102, 104 at the joint 106 with the lower pack frame 104
positioned closer to the wearer than the upper pack frame 102.
[0053] With the upper pack frame 102 positioned closer than the
lower pack frame 104, the lower pack frame 104 may not be in
constant contact with the lower torso of the wearer and may
potentially not follow the wearer's movements as closely. FIG. 2C
in particular shows how the curvature of the pack frame 100 relates
to a curvature profile of a back of a wearer. In other embodiments,
the pack frame 100 may roughly follow the curve of the spine, with
the joint 106 at about the waist or upper sacral region of the
body.
[0054] The rear side 200 of the upper pack frame 102 and the rear
side 202 of the lower pack frame 104 may be fitted with cushions or
padding to improve comfort, grip, and/or zonal flexibility of the
pack frame 100 against the wearer.
[0055] FIGS. 3A-3D show exploded views of the joint 106 relative to
the upper and lower pack frames 102, 104. FIG. 3A is a perspective
rear view, FIG. 3B is a perspective front view, FIG. 3C is a bottom
view, and FIG. 3D is a side view. Along a central axis (A), the
rearward direction extends toward the end of the joint 106 having
an adjustment cap 300, and the forward direction extends toward the
end of the joint 106 having an internal cap 308. A first resilient
member 302 is positioned between the adjustment cap 300 and the
upper pack frame 102. A protective ring 304 is positioned between
the first resilient member 302 and the upper pack frame 102. A
second resilient member 306 is positioned between the upper pack
frame 102 and the lower pack frame 104. An internal cap 308 is
attachable to the adjustment cap 300 to hold the lower pack frame
104 between the internal cap 308 and the second resilient member
306.
[0056] The adjustment cap 300 may be comprised of a rigid material,
such as, for example, a metal or polymer. The outer surface of the
adjustment cap 300 may be configured with ridges 310. The ridges
310 may facilitate hand-tightening of the adjustment cap 300
relative to the rest of the joint 106. In some embodiments, the
outer surface may have holes or other features to receive tools to
tighten the cap 300. The stem 312 of the adjustment cap 300 may be
threaded. The frontal face 314 (see FIG. 3B) of the adjustment cap
300 may be generally flat. The adjustment cap 300 may be threadably
attachable to the internal cap 308 using the stem 312 and threads
on the internal cap 308. The threaded attachment of the adjustment
cap 300 and the internal cap 308 may tighten or loosen the
connection between the upper and lower pack frames 102, 104,
thereby adjusting the force required to move the upper and lower
pack frames 102, 104 relative to each other, as described in
further detail below.
[0057] The first resilient member 302 may be comprised of a
relatively resilient or elastic material, such as, for example,
rubber or a flexible polymer or composite. If an elastomer is used,
the elastomer may be chosen to provide dampening qualities, even if
the member 302 is not immediately elastic. The resilient member 302
is generally annular in shape and sized to receive the stem 312 of
the adjustment cap 300 through an opening in its center. Other
shapes securable between the adjustment cap 300 and the upper pack
frame 102 may also be implemented, such as, for example, a partial
annulus (i.e., C-shape), a square having an opening in its center,
and the like. The rearward surface 316 of the first resilient
member 302 may be generally flat and engage the frontal face 314 of
the adjustment cap 300. The surface profiles of the rearward
surface 316 and the frontal face 314 may therefore correspond to
each other, and non-planar shapes may also be implemented. For
example, a curved rearward surface 316 may fit with a frontal face
314 that has a correlating curved surface shape.
[0058] In some embodiments, the rearward surface 316 may comprise a
circumferential lip (not shown) extending rearward from the edge of
the rearward surface 316. The circumferential lip may help keep the
first resilient member 302 aligned with the adjustment cap 300 and
may extend around the outside edge of the frontal face 314 of the
adjustment cap when the joint 106 is assembled. The circumferential
lip may prevent the adjustment cap 300 from sliding relative to the
rearward surface 316 when the joint 106 is torsionally flexed
(e.g., around axes B or C in FIG. 5B).
[0059] The thickness (t.sub.1) of the outer perimeter or
circumference of the first resilient member 302 may vary around the
central axis (A) of the joint. See, e.g., FIGS. 3C and 3D, showing
profile views of the first resilient member 302. The thickness of
the first resilient member 302 may thus follow the shape of the
rear surface 317 surrounding the opening 318 in the upper pack
frame 102. FIG. 3C shows the convex shape of the rear surface 317
around the opening 318 and the corresponding concave of the
thickness of the first resilient member 302 extending from the
rearward surface 316. As shown in FIG. 3D, the circular shape of
the first resilient member 302 may cause the concave of the
thickness of the first resilient member 302 to produce a convex
curve when viewed from the side.
[0060] Varying thickness of the first resilient member 302 may
affect the elastic properties of the pack frame 100. For example,
with a convex rear surface 317 around opening 318 and a concave
shaped first resilient member 302 (when viewed from its bottom
profile), the first resilient member 302 may interlock and engage
the rear surface 317 with the thinnest thicknesses 319-a of the
first resilient member 302 oriented vertically relative to the
wearer. In this configuration, rotation of the upper pack frame 102
relative to the first resilient member 302 may produce relative
rotation of the convex and concave surfaces. For example, as the
upper pack frame 102 is rotated relative to the joint 106 (and
therefore also relative to the first resilient member 302), the
position of the upper pack frame 102 may change orientation between
the orientations shown in FIGS. 5A and 5C. The relative rotation
may then cause the convex thicker portions 319-b of the first
resilient member 302 to rotate into engagement with the convex area
of the rear surface 317 and resiliently deform (i.e., compress)
between the rear surface 317 of the upper pack frame 102 and the
frontal face 314 of the adjustment cap 300. This deformation may
require additional force and effort from the wearer to produce the
rotation of these elements. If the upper pack frame 102 is rotated
back from the orientation of FIG. 5C to the orientation of FIG. 5A,
the thick portions 319-b of the first resilient member 302 may then
deform again (i.e., expand), assisting the wearer in completing
this motion. In such embodiments, the surface features of the upper
and/or lower pack frames 102, 104 that interact with (e.g.,
interlock with) the resilient members 302, 306 may be referred to
as portions of the joint. The first resilient member 302, ring 304,
and second resilient member 306 may optionally include alignment
indicators 342 to assist in properly aligning them when assembling
the joint 106.
[0061] The resistance and assistance provided by the first
resilient member 302 when making lateral rotation of the upper pack
frame 102 relative to the joint 106 may beneficially establish a
"default" or "at rest" orientation of the pack frame 100, where
potential energy in the joint 106 is at its lowest. The default
orientation of the pack frame 100 may be beneficially configured as
an upright, weight-bearing position for the wearer. This
orientation may provide the wearer with assistance in keeping the
pack upright and keeping upright posture, but other orientations
may be selected, as required in each individual embodiment. In some
embodiments, the shape (e.g., curvature) of the first resilient
member 302 may thus be configured to provide a "snap-back" position
and an orientation of the pack frame 100 from which increased
effort may be required to move the resilient member 302. As the
upper pack frame 102 is reoriented, the first resilient member 302
may be configured to bias the upper pack frame 102 back to a
default orientation relative to the joint 106 and/or lower pack
frame 104.
[0062] The first resilient member 302 may also act as a shock
absorber which dampens vibration or other forces between the
adjustment cap 300 and the upper pack frame 102. This may enhance
comfort of the pack frame, decrease wear on rigid components of the
frame, and allow relative pivoting or rotational movement between
elements of the pack frame along an axis perpendicular to axis A.
Shock absorption and dampening may be provided around three axes of
rotation. See, e.g., FIG. 5B and related description, infra,
illustrating additional rotation axes B and C.
[0063] Although the embodiments shown in the figures show a first
and a second resilient member 302, 306, in some embodiments, only
one resilient member may be present. If the first resilient member
302 is the one present, relative rotation between the upper and
lower pack frames 102, 104 may be provided since the upper pack
frame 102 may compress the first resilient member 302 against the
frontal face 314 of the adjustment cap 300, and the adjustment cap
300 may be rigidly attached to the internal cap 308 and/or the
lower pack frame 104. This compression may provide clearance and
relative rotation between sections of the upper and lower pack
frames 102, 104. In embodiments where only the second resilient
member 306 is present, relative rotation between the upper and
lower pack frames 102, 104 may be provided by compression of the
second resilient member 306 between the front surface 330 and the
surface surrounding the receiver extension 336 on the lower pack
frame 104.
[0064] In some arrangements, the rear surface 317 of the upper pack
frame 102 may be concave and the positions of the thin edges 319-a
and thick edges 319-b may be reversed accordingly to fit the
concavity of the rear surface 317 similar to how their illustrated
positions correspond to the convexity of the illustrated rear
surface 317. In other arrangements, the rear surface 317 may be
flat, and the paired convex/concave surfaces may be the rearward
surface 316 of the first resilient member 302 and the frontal face
314 of the adjustment cap 300.
[0065] Other surface features may be implemented using the design
features and guidelines described herein, as will be apparent to
those skilled in the art having the benefit of the present
disclosure. For example, a V-shaped surface may be used in place of
a concave described and illustrated herein. Furthermore, the rear
surface 317 may bear ridges, nubs, or notches that align with
corresponding notches, depressions, or ridges on the first
resilient member 302 or vice versa. These and other like designs
would bias the upper and lower pack frames 102, 104 into a default
orientation and/or resist reorientation out of a default
orientation while still allowing elastic deformation of the first
resilient member 302 under sufficient forces, providing similar
benefits to the illustrated embodiments described in greater detail
above.
[0066] The ring 304 is an optional feature of the joint 106 that
may be positioned between the upper pack frame 102 and the first
resilient member 302. The ring 304 may be comprised of a material
allowing smooth sliding motion between the ring 304 and the first
resilient member 302. The ring 304 may protect the first resilient
member 302 and second resilient member 306 from shear forces
produced by the upper pack frame 102 as it rotates relative to the
first resilient member 302 by providing a rigid surface configured
to be slidable against the first resilient member 302. See also
FIGS. 4A-4B and their related description, infra. The ring 304 may
also have a contoured shape that follows the profile (e.g.,
convex/concave) of the rear surface 317 of the upper pack frame 102
and a sliding surface 320 (see FIG. 3B) of the first resilient
member 302. See, e.g., the curved shape of the ring 304 in FIGS. 3C
and 3D. In some embodiments, the ring 304 may be referred to as a
rigid member.
[0067] In the illustrated configuration, the ring 304 may be
inserted into the opening 318 in the upper pack frame 102, with
circumferential ridges 322 on the ring 304 insertable into
circumferential notches 324 of the opening 318 and the
circumferential notches 324 of the circular groove 326 of the
second resilient member 306 (see FIG. 3A). Thus, the ring 304 is
not rotatable relative to the upper pack frame 102 or the second
resilient member 306 after insertion. The ring 304 may be comprised
of a smooth, rigid material such as, for example, nylon, that
allows sliding motion of the first resilient member 302 where it
contacts the ring 304 at the sliding surface 320. Thus, when the
upper pack frame 102 translates laterally relative to the lower
pack frame 104 and/or other portions of the joint 106 (e.g.,
perpendicular to axis A), the ring 304 may distribute the shear
force at the opening 318 across the outside surface of the ring 304
and into the first and second resilient members 302, 306. This
outside surface is relatively broad in comparison to to the
thickness of the upper pack frame 102. Thus, the ring 304 may allow
the upper pack frame 102 to be thin and light without cutting or
otherwise shearing the first and/or second resilient members 302,
306.
[0068] In some embodiments, the ring 304 may have ridges 322
configured to engage notches (not shown) in the first and second
resilient members 302, 306, thereby linking rotation of the ring
304 to the resilient members instead of to the upper pack frame
102. It may be beneficial to configure the ring 304 in this manner
since the ring 304 and upper pack frame 102 are typically each more
rigid than the resilient members 302, 306 and it may thus be easier
for them to slide against each other, but the ring 304 may also
need to be thinner to be able to fit between the adjustment cap 300
and the lower pack frame 104 when they are not in the default
orientation dictated by the shape of the resilient members 302,
306.
[0069] The ring 304 may also have a circumferential lip 402. See
FIG. 4A. This lip 402 may prevent the ring 304 from passing through
the upper pack frame 102 and may provide a surface on which the
first resilient member 302 may slide.
[0070] The second resilient member 306 may be comprised of a
resilient, elastic material such as rubber or a flexible polymer.
The second resilient member 306 may be positioned between the upper
and lower pack frames 102, 104. The second resilient member 306 may
have a general shape similar to the first resilient member 302,
such as, for example an annular shape or another shape having an
opening therein. The thickness of the second resilient member 306
may vary around the central axis A, with thinner portions 328-a and
thicker portions 328-b circumferentially spaced. While two thinner
portions 328-a and two thicker portions 328-b are shown herein,
other configurations may include three or more alternating thinner
and thicker portions instead.
[0071] In an exemplary embodiment, shown in FIGS. 3A-3D, the front
surface 330 of the upper pack frame 102 may be concave (see FIG. 3C
particularly), so the thicker portions 328-b may be oriented
vertically and the thinner portions 328-a may be oriented laterally
when the upper pack frame 102 is in the default, upright
orientation relative to the lower pack frame 104. Similar to the
description above regarding the shape of the first resilient member
302 and the rear surface 317, the front surface 330 and the second
resilient member 306 may be formed with interlocking or adjoining
surfaces that may bias the upper pack frame to a default
orientation. For example, the front surface 344 of the second
resilient member may have resilient setoffs or bumps (not shown)
extending from the front surface 344 toward the lower pack frame
104, and the lower pack frame 104 may comprise small depressions
surrounding the receiver extension 336 that receive the setoffs
when the front surface 344 is in an upright orientation.
Alternatively, the setoffs and depressions may be reversed, with
the setoffs extending from the lower pack frame 104. In another
embodiment, the setoffs and depressions may appear on the surfaces
of the upper pack frame 102 and the second resilient member 306
that come into contact. With a generally constant-thickness upper
pack frame 102, the thickness t.sub.2 of the second resilient
member 306 may be analogous to the thickness t.sub.1 of the first
resilient member 302, with thicker portions of one resilient member
being adjacent to thinner portions of the other.
[0072] In embodiments where the ridges 322 of the ring 304 are
inserted into notches 324 in the circular groove 326 of the second
resilient member 306, the second resilient member 306 may
simultaneously rotate around the central axis A with the upper pack
frame 102. Thus, the thicker portions 328-b and thinner portions
328-a of the second resilient member 306 may remain oriented
relative to the front surface 330 and the opening 318 in the same
manner as when they are in the default orientation. In other
embodiments, the ring 304 may not have ridges 322 or the circular
groove 326 may be wide enough to receive the ridges 322 yet allow
the ring 304 to rotate within the circular groove 326. In these
embodiments, the second resilient member 306 may rotate independent
of the upper pack frame 102.
[0073] The second resilient member 306 may comprise a central post
332 between the circular groove 326 and the central opening through
the second resilient member 306. See FIGS. 3A, 3C, and 3D. The
central post 332 may be an extension of the resilient material that
has greater height than the thinner and thicker portions 328-a,
328-b of the second resilient member 306. The extra height of the
central post 332 may increase the surface area of the second
resilient member 306 that contacts the ring 304. The extra height
may also allow the central post 332 of the second resilient member
306 to contact the first resilient member 302 when the joint 106 is
assembled. See also FIGS. 4A-4B.
[0074] In some embodiments, the first resilient member 302 may also
have a central post 334 that may come into contact with the central
post 332 of the second resilient member 306. See FIGS. 3B, 3C, and
3D. Upon assembly, the distance between the sliding surface 320 and
the bottom of the circular groove 326 may therefore be about equal
to the height of the ring 304. In this configuration, the ring is
securely held in place by the resilient members 302, 306 and the
opening 318 of the upper pack frame 102, even during rotation
around axis A or another axis perpendicular thereto. A close fit
may thus keep debris and dirt out of the joint 106 and keep the
joint clean and operating smoothly.
[0075] The second resilient member 306 may rotate independent of
the lower pack frame 104, such as by rotating around a receiver
extension 336 coming from the lower pack frame 104. The receiver
extension 336 may receive the internal cap 308 from the front of
the joint 106 and may fit within the first and/or second resilient
members 302, 306 of the joint 106 upon assembly as well. See also
FIGS. 4A-4B. The surface of the receiver extension 336 may
beneficially be at a 10-degrees-or-greater angle relative to the
central axis A. In a preferable embodiment, this surface may be at
about 15 degrees relative to the central axis A to facilitate
molding construction of the lower pack frame 104. In other
embodiments, such as those where the lower pack frame 104 is not
molded, the surface of the receiver extension 336 may be angled at
less than 10 degrees relative to the central axis A. This may allow
the joint 106 to be more compact and may provide more rigidity in
the joint during torsional flexion.
[0076] The rear side of the lower pack frame 104 around the
receiver extension 336 may be smooth and shaped to slidably receive
the second resilient member 306. In some embodiments, the second
resilient member 306 may be attached to the rear side of the lower
pack frame 104 around the receiver extension 336 by an adhesive,
interference of parts, or another attaching means. Preferably, the
ring 304 may slidably rotate within the circular groove 326
relative to the second resilient member 306 if the second resilient
member 306 is attached to the lower pack frame 104.
[0077] The inclusion of two resilient members may allow greater
cumulative deformation of the resilient members 302, 306 by the
upper pack frame 102. This may provide smoother axial rotation of
the upper pack frame 102 away from the default orientation and may
also provide increased biasing forces to bring the upper pack frame
102 back into the default orientation, since the resilient members
may apply a force to both side surfaces 317, 330 of the upper pack
frame 102. Additionally, having resilient members on each side of
the upper pack frame 102 may allow easier movement of the upper
pack frame 102 relative to the lower pack frame 104 around an axis
perpendicular to central axis A. This torsional motion of the pack
frames 102, 104 may be accommodated by compression of both of the
resilient members 302, 306 on each side of the opening 318 (i.e.,
on opposing sides of the resilient members 302, 306). See also FIG.
5B and its related description below.
[0078] The internal cap 308 may be received by the lower pack frame
104 from the front of the receiver extension 336. The internal cap
308 may be internally threaded to receive threads of the stem 312
of the adjustment cap 300. Using a threaded internal cap 308 and
stem 312, the tightness joint 106 may be adjustable to allow more
or less resistance to axial and/or off-axial relative rotation of
the upper and lower pack frames 102, 104. For example, tightening
the threaded connection of the internal cap 308 and adjustment cap
300 may force the first resilient member 302 to partially deform
(e.g., compress) into the upper pack frame 102, thereby decreasing
the amount of potential deformation of the resilient member upon
reorientation of the upper pack frame 102 and increasing frictional
forces between the resilient member and the upper pack frame
102.
[0079] The internal cap 308 may have an outer surface 338
configured to engage an inner surface 340 of the receiver extension
336. For example, the outer surface 338 may be faceted such that it
may be received by the inner surface 340 without allowing rotation
of the internal cap 308 after insertion. In another embodiment, the
outer surface 338 may have one or more extension that may be
received by the inner surface 340 that prevents rotation of the
internal cap 308, or vice versa. The internal cap 308 may thus be
restricted from rotating relative to the lower pack frame 104 due
to the engagement of the outer and inner surfaces 338, 340. By
preventing rotation of the internal cap 308, the adjustment cap 300
may be more easily turned relative to the internal cap 308 using
the ridges 310. This may advantageously allow a user to adjust the
tension in the joint 106 with access to only the rear end of the
joint 106, as may be the case if the pack frame 100 is installed in
a backpack with pouches, sleeves, and other material covering the
front end of the joint 106 around the internal cap 308. The
threaded connection between the adjustment cap 300 and the internal
cap 308 may also be configured to prevent the internal cap 308 from
being removed from the stem 312 while installed in a backpack, such
as by limiting the rotation of the threads of the stem 312 at a
point to prevent inadvertent removal of the internal cap 308. In
this fashion, the internal cap 308 may not be easily lost or
disconnected within the backpack while the pack frame 100 is
installed. In some embodiments, the internal cap 308 may rotate
within the receiver extension 336. In yet other embodiments, the
stem 312 may lock into position upon being completely received by
the internal cap 308, thereby preventing removal of the adjustment
cap 300 from the internal cap 308, or the internal cap 308 may be
bonded into place, such as, for example, by an adhesive between the
internal cap 308 and the lower pack frame 104. In other
embodiments, the adjustment cap 300 may be removably attached to
the internal cap 308, so the rest of the joint 106 (e.g., resilient
members 302, 306) may also be removable from the pack frame
100.
[0080] The internal cap 308 may also be attached to the stem 312
using other means, such as, for example, glue or another adhesive,
a weld, press fit, or interference of parts. In some embodiments,
the role of the internal cap 308 and the adjustment cap 300 may be
reversed, such that the internal cap 308 may have ridges (e.g.,
similar to ridges 310) and a stem extending into threaded
connection with a threaded hole in the adjustment cap 300. The role
of other parts may also be exchanged without departing from the
principles and elements of the present disclosure.
[0081] FIG. 4A shows a bottom section view through section lines 4A
in FIG. 2B. FIG. 4B shows a left side section view through section
lines 4B in FIG. 2B. Thus, FIGS. 4A and 4B illustrate orthogonal,
central section views of the assembled joint 106. The most rearward
element is the adjustment cap 300, followed by the first resilient
member 302, ring 304 and upper pack frame 102, second resilient
member 306, lower pack frame 104, and internal cap 308. As shown in
these figures, the stem 312 of the adjustment cap 300 may extend
through the internal cap 308 completely upon tightening.
[0082] The first resilient member 302 may be compressed between the
frontal face 314 of the adjustment cap 300 and the receiver
extension 336 into the shape shown. In this configuration, the
opening in the receiver extension 336 may contact a portion of the
stem 312 and therefore apply less shear force to one of the
resilient members 302, 306 upon lateral movement of the lower pack
frame 104 relative to the resilient members 302, 306. The
adjustment cap 300 may have a stem shaft surface 400 configured to
allow slidable rotation of the receiver extension 336 around the
stem 312. In other embodiments, the lower pack frame 104 may be
linked in rotation with the adjustment cap 300 due to the threads
of the internal cap 308 in order to prevent the adjustment cap 300
from unthreading from the internal cap 308.
[0083] FIGS. 4A-4B also show the varying thicknesses of the first
first and second resilient members 302, 306 and the ring 304. The
thickness of the ring 304 in FIG. 4A appears thinner than the
thickness in FIG. 4B due to the ridges 322 of the ring 304 being
within section lines 4B. The rearward portion of the ring 304 may
have a lip 402 that prevents the ring 304 from passing completely
through the opening 318 in the upper pack frame 102. The lip 402 is
not visible in FIG. 4B due to the increased thickness of the ring
304 subsuming the lip 402 at the ridges 322.
[0084] FIGS. 4A-4B also illustrate how the entire height of the
ring 304 may contact the first and second resilient members 302,
306. The height of the ring 304 is shown to be significantly
broader than the thickness of the upper pack frame 102 and is
distributed across the boundary between the first and second
resilient members 302, 306, so that the ring 304 may prevent
shearing of the resilient members 302, 306 by the upper pack frame
102 and may also prevent the upper pack frame 102 from sliding
between the resilient members 302, 306 where they come into contact
with each other. For example, the ring 304 may prevent the upper
pack frame 102 from coming into contact with the central posts 332,
334. The first resilient member 302 may therefore slide more easily
relative to the upper pack frame 102, and it may be subject to less
wear than if its central post 334 was in contact with the opening
318 of the upper pack frame 102.
[0085] The thickness of the first resilient member 302 in FIG. 4A
corresponds with the thicker portions 319-b, and the thickness of
the first resilient member in FIG. 4B corresponds with the thinnest
thicknesses 319-a. These figures therefore show the approximate
amount of compression required for the thicker portions 319-b to
rotate into the position of the thinnest thicknesses 319-a. The
thinner portions 328-a and thicker portions 328-b of the second
resilient member 306 are also shown in FIGS. 4A and 4B,
respectively, thus showing how the second resilient member 306
conforms to the front surface 330 of the upper pack frame 102.
Additionally, the thicknesses 328-a, 328-b of the second resilient
member 306 are greater than the thicknesses 319-a, 319-b of the
first resilient member 302. If the second resilient member 306 is
made of the same material as the first resilient member 302, the
second resilient member 306 may therefore have a greater capacity
for compressive deflection than the first resilient member 302.
This may allow easier relative torsional motion of the upper and
lower pack frames 102, 104 than relative lateral pivotal motion
(i.e., around central axis A of the joint 106). In embodiments
where the second resilient member 306 may rotate relative to the
upper pack frame 102, these views also show the amount of
compression needed to complete a rotation (i.e., a rotation of the
thicker portion 319-b from FIG. 4B to the position of the thinnest
thicknesses 319-a of FIG. 4A).
[0086] The width W of the joint 106 may be wide to improve the
stability of the joint 106. A narrower width W may increase the
pivotability of the joint 106 along an axis perpendicular to the
central axis A, and a wider joint 106 may decrease pivotability.
The opening 404 of the adjustment cap 300 is shown open, which may
decrease weight and cost of materials, but in some embodiments the
interior of the adjustment cap 300 may be narrower, walled off, or
filled, which may increase strength and help prevent debris from
getting to the front side of the joint 106. In embodiments having
an through-hole at the opening 404, a user may reach to the front
of the joint 106, such as to recover an internal cap 308 that comes
off of the stem 312, to clean the front of the joint 106, or to
hold the internal cap 308 in place while the adjustment cap 300 is
tightened (in appropriate embodiments). Thus, the opening 404 in
the adjustment cap 300 may be large enough to receive a finger,
hand, or tool of a user depending on the purposes for which the
opening 404 is designed.
[0087] The outer surfaces 406, 408 of the resilient members 302,
306, may be sloped or beveled. Sloped outer surfaces 406, 408 may
resist deformation less than straight (i.e., completely horizontal
or vertical) outer surfaces 406, 408, so the profile of the outer
surfaces 406, 408 may increase flexibility of the joint 106 in both
axial and off-axial rotation. Shaped (e.g., sloped) outer surfaces
406, 408 may also have controlled deformation, such as reduced
buckling or expansion in a desired direction. Other profile shapes
of the outer surfaces 406, 408 may be selected based on desired
flexibility and compression characteristics of the joint 106, such
as, for example, chamfered, stepped, semicircular, and other shapes
that would be apparent to those skilled in the art having the
benefit of the present disclosure.
[0088] FIGS. 5A-5C illustrate how a pack frame apparatus 500 may be
positioned and moved relative to a user U. For convenience in
viewing and understanding the operation of the pack frame apparatus
500, straps, bags, pads, and other features of a backpack that
would attach to the user U or the pack frame apparatus 500 are
omitted.
[0089] In FIG. 5A, the user U has the pack frame apparatus 500
positioned on his back with the upper pack frame 502 positioned
relative to his upper torso and the lower pack frame 504 positioned
relative to his lower back/sacral area. The upper pack frame 502 is
connected to the lower pack frame 504 by joint 506. The user U is
standing vertically upright (i.e., in a coronal or frontal plane
vertically splitting his anterior and posterior sides), and the
upper and lower pack frames 502, 504 are roughly vertically aligned
at the joint 506 (i.e., also in the coronal or frontal plane). In a
preferable embodiment, this upright position may be the default
orientation of the pack frame apparatus 500. In this position, the
weight borne by the pack frame apparatus 500 may be evenly
distributed to both shoulders and both sides of the waist and hips,
so the user U may feel less fatigue while bearing a load in this
position. Additionally, in this position the joint 506 may
optimally absorb shock along all three axes of rotation (i.e., axes
A (see FIG. 3A), B, and C) since the resilient portion(s) of the
joint 506 are not pre-loaded. Therefore, resilient members between
the upper and lower pack frames 502, 504 (e.g., first and/or second
resilient members 302, 306 of FIGS. 3A-4B) and the surfaces of the
upper and lower pack frames 502, 504 near the joint 506 may be
shaped to be inclined to stay in this position. In some
embodiments, there may be no default orientation, and the pack
frame apparatus 500 may pivot at the joint laterally (e.g., in the
manner shown in FIG. 5C) without requiring additional resistance to
reposition the upper and lower pack frames 502, 504 relative to
each other.
[0090] FIG. 5B is an illustration of the pack frame apparatus 500
flexing in torsion due to rotation of the upper torso of the user
U. The upper and lower pack frames 502, 504 are still positioned in
approximately the same positions relative to the respective parts
of the user U as in FIG. 5A, but now the joint 506 has flexed so
that the upper pack frame 502 has rotated around axes B and/or C.
Axes B and C are parallel to (or co-planar with) the coronal plane
described in connection with FIG. 5A. The forward part of the joint
506 (e.g., its internal cap 308) is unmoved relative to FIG. 5A
since the lower pack frame 504 has not moved relative to FIG. 5A,
but the upper pack frame 502 has rotated. During energetic
activities, movement of the upper pack frame 502 around axes B and
C allows the pack frame apparatus 500 to be secured more closely to
the user U by following his natural body motions. The amount of
flexure that permits rotation around axes B and C may be limited by
the compressibility and thickness of the materials used as
resilient members between the upper and lower pack frames 502, 504.
In an exemplary embodiment, the pack frame apparatus 500 may allow
torsional rotation of up to at least about 20 degrees around axes B
and/or C. Controlling the flexibility of the joint 506 may help
prevent the pack frame apparatus 500 from damaging a cover,
pouches, and other equipment attached thereto. Limiting the
flexibility of the joint 506 using resilient materials may also
allow the joint 506 to bias the upper and lower pack frames 502,
504 into the aligned position of FIG. 5A when they are in the
positions of FIG. 5B or 5C.
[0091] Resilient rotation around axis B would correspond with a
twisting motion of the wearer (i.e., rotation around the spine),
and resilient rotation around axis C would correspond with a
bending motion of the wearer (i.e., bending forward toward the toes
or arching the spine). The joint 506 may facilitate one or more of
these resilient rotational movements. In some embodiments, the
joint 506 may also provide resilient rotational movement around
axis A, as depicted in FIG. 5C.
[0092] FIG. 5C illustrates the pack frame apparatus 500 pivoting
laterally at the joint 506 in response to the user U leaning
laterally to his right (i.e., within the coronal plane of the joint
or around an axis normal to the coronal plane). In an exemplary
embodiment, the pack frame apparatus 500 may allow pivotal motion
in this plane of at least about 45 degrees relative to the vertical
position. In some embodiments, the pivotal motion may be at least
about 30 degrees in this plane. Similar to the pack frame apparatus
of FIG. 5B, the lower pack frame 504 remains motionless relative to
the user U but the upper pack frame 502 rotates with his upper
torso. In the embodiment shown, the joint 506 may have very low
friction and resistance. In embodiments where there is curvature to
a resilient member between the upper and lower pack frames 502, 504
or between at least one of the upper and lower pack frames 502, 504
and the joint 506 (e.g., an adjustment cap 300 or internal cap
308), and therefore there is resistance to relative pivoting
between the upper and lower pack frames 502, 504, the lower pack
frame 504 would likely rotate slightly at the joint 506 due to
biasing forces provided by the resilient member(s) attempting to
align the upper and lower pack frames 502, 504. The lower pack
frame 504 may also be in the position shown in FIG. 5C due to
straps attaching the lower pack frame 504 around portions of the
user U that have not moved between FIGS. 5A and SC, such as around
the pelvis of the user U.
[0093] While using the pack frame apparatus 500, the user U may
naturally move in multiple directions simultaneously. For example,
the user U may pivot the joint 506 while torquing the upper and
lower pack frames 502, 504 simultaneously. Thus, the motions of
FIGS. 5B and 5C may be enacted at once. The pack frame apparatus
500 may follow these natural movements while bearing a load and
while being attached or strapped to the user U. The upper and lower
pack frames 502, 504 may therefore be beneficially constructed of
rigid, weight-bearing materials since the joint 506 provides
flexibility at the crucial mid-torso area. The pack frame apparatus
500 may also be beneficially positioned nearer to the torso of the
user U throughout these motions than a rigid pack frame would be,
providing the user U with improved balance and less shaking or
other motion of the pack and/or its contents while in motion.
[0094] Another embodiment may include a method of providing a pack
frame apparatus. The method may comprise providing a first plate
and a second plate, wherein the first and second plates may be
adapted to provide structural support to a pack frame. The first
plate may be positioned for support of an upper back portion of a
user through attachment to a shoulder strap, and the second plate
may be positioned for support of a lower back portion of the user
through attachment to a waist strap. The method may also comprise
pivotally joining the first plate with the second plate such that
the plates are relatively rotatable in at least a first direction
and resiliently relatively rotatable in a second direction. Thus,
the plates may rotate in a first direction without resilient
resistance, and the plates may rotate in a second direction with
resilient resistance. In another embodiment, the plates may rotate
in the first direction with resilient resistance as well. The
resilient resistance may cause the plates to bias to a default
orientation. For example, the resilient resistance may bias the
plates toward a vertical, upright position with the first and
second plates about parallel where they are joined together.
[0095] The first and second plates may be broad, generally flat
parts and at least semi-rigid in comparison to the resilient
features that join them. In some embodiments, portions of the
plates may be more flexible than others, such as, for example, by
having a more flexible material where they are joined, or by having
openings or relief holes in portions of the plates that allow them
to resiliently deflect or deform. The plates may have openings,
slots, or holes through their surfaces to reduce weight, increase
zonal flexibility, or for other reasons, such as those set forth
above in connection with the slots 110, 112 and openings 116 of the
upper and lower pack frames 102, 104.
[0096] The method may also include a step of joining the first
plate with the second plate by inserting a resilient member between
the first and second plates. The first and second plates may then
be joined for pivotal movement along the first direction around the
inserted resilient member. In another embodiment, the method may
include attaching the joined first and second plates with a
backpack having shoulder straps and a storage compartment. In some
embodiments, the relative rotation of the first and second plates
may be adjusted in at least the second direction by tightening or
loosening a member joining the first and second plates. In some
embodiments, this may entail adjusting part of the joint (e.g., an
adjustment cap 300) relative to the rest of the joint or the
plates. The relative rotation between the first and second plates
may be biased to assume a default position in at least one of the
at least two directions. This may be accomplished in the manner
described in connection with FIGS. 3A-3D above. Additional steps
may include forming and arranging the parts of the joint 106 and
upper and lower pack frames 102, 104 as described above. In some
embodiments, the steps of these methods may be reordered or
combined.
[0097] The previous description of the disclosure is provided to
enable a person skilled in the art to make or use the disclosure.
Various modifications to the disclosure will be readily apparent to
those skilled in the art, and the generic principles defined herein
may be applied to other variations without departing from the
spirit or scope of the disclosure. Throughout this disclosure the
term "example" or "exemplary" indicates an example or instance and
does not imply or require any preference for the noted example.
Thus, the disclosure is not to be limited to the examples and
designs described herein but is to be accorded the widest scope
consistent with the principles and novel features disclosed
herein.
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