U.S. patent number 3,733,017 [Application Number 05/126,408] was granted by the patent office on 1973-05-15 for adjustable pack frame.
This patent grant is currently assigned to K2 Corporation. Invention is credited to Murray J. Pletz.
United States Patent |
3,733,017 |
Pletz |
May 15, 1973 |
**Please see images for:
( Certificate of Correction ) ** |
ADJUSTABLE PACK FRAME
Abstract
A pack frame for hikes which is light and flexes with movement
of the wearer's body. The majority of the carried weight is
supported by the hips and the pack is adjustably suspended within
the frame such that it may be placed in the most comfortable
position relative to the frame. Shoulder straps are provided to
keep the pack from pivoting about the weight supporting belt but
carry very little strain themselves. The shoulder straps themselves
are adjustable as to length and pivotable about the anchor points
thus making the pack extremely versatile and comfortable for
wearers of varying stature.
Inventors: |
Pletz; Murray J. (Bellevue,
WA) |
Assignee: |
K2 Corporation (Vashon,
WA)
|
Family
ID: |
22424659 |
Appl.
No.: |
05/126,408 |
Filed: |
March 22, 1971 |
Current U.S.
Class: |
224/634; 224/235;
224/635; 224/636 |
Current CPC
Class: |
A45F
3/08 (20130101) |
Current International
Class: |
A45F
3/08 (20060101); A45F 3/04 (20060101); A45f
003/00 () |
Field of
Search: |
;224/6,8,25R,25A |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
Primary Examiner: Forlenza; Gerald M.
Assistant Examiner: Forsberg; Jerold M.
Claims
The embodiments of the invention in which a particular product or
privilege is claimed are defined as follows:
1. A flexible pack frame for hikers, comprising;
a pair of relatively rigid side members,
a transverse bottom member inter-connecting the side members,
a transverse top member connecting the side members,
at least one transverse intermediate member, adjustable along the
side members, and capable of being locked at an infinite number of
positions along the side members,
an adjustable belt attached adjacent the bottom portion of the side
members and adapted to encircle and be tightened about the waist
portion of the wearer and bear the weight of the pack,
a pair of non-weight bearing shoulder straps having a first end
attached to the belt and having a second end attached to the bottom
portion of the adjustable transverse member said straps adapted to
pass over the shoulders of the wearer and prevent movement of the
pack outwardly from the wearer's body, the connection between the
second end and the transverse member permitting the distance
between the straps to vary and permitting relatively free pivotal
movement of said straps,
said shoulder straps including pads to cushion the wearer's
shoulders and means whereby the length of the straps may be
adjusted fitting the pack to the individual while keeping the pads
centered upon the shoulder.
2. A frame as in claim 1 and further including a shelf extending
rearwardly from the top portion adapted to have a pack suspended
therefrom thereby placing the effective weight moment high on the
frame and thus high upon the wearer.
3. A frame as in claim 2 wherein the shelf is adjustable along the
length of the side members thus enabling the placement of the
weight at a position of greatest comfort for the wearer.
4. A pack frame as in claim 2 and further including a pack bag
suspended from the shelf and having a covered storage area above
the shelf.
5. A pack frame as in claim 2 and further including a pack bag
suspended from the shelf and having pockets closed by a pair of
opposed zippers allowing access to the pack from any portion of the
opening without disturbing the rest of the contents or exposing
them to the elements.
Description
BACKGROUND OF THE INVENTION
The present invention relates to apparatus for transporting loads
on a man's back. Specifically the present invention relates to an
improved pack frame which effects optimum distribution of a load to
the human body, utilizing a simplified versatile structure.
It is commonly understood that a load is most easily endured by the
human body if it is positioned above the shoulders and close in to
the neck. Placement of the load in this manner directs the weight
through the shoulders and torso to the hips enabling the strongest
body muscles to bear the major bulk of the burden. Prior art pack
frames seeking to effect the foregoing load placement have employed
complicated frame structures and elaborate shoulder harnesses.
Accordingly it is an object of the present invention to construct a
pack frame of simple and economical structure and assembly capable
of optimumly distributing the weight of the load to the hip portion
of the body without the necessity of passing through the upper
torso. To accomplish this objective the present invention employes
a generally L-shaped frame having shoulder straps for retaining the
load close to the body of the wearer. A waist belt is coupled to
the frame near the foot of the frame to secure the lower end of the
pack frame to the body and to absorb a major portion of the
load.
It is another object of the present invention to construct a pack
frame which can be readily altered in size to accommodate different
types of loads and for use in different environments.
It is also an object to construct a pack frame so that it may be
completely disassembled and repaired or modified. This object is
accomplished by constructing the pack frame from interlocking parts
held in place by the tension forces developed in the shoulder
straps and other straps holding comfort pads against the back of
the bearer.
Accordingly another object of the invention is to design a pack
frame having a flexible frame structure capable of absorbing shock
when dropped to the ground or the like when fully loaded.
Yet another object of the present invention is to provide a pack
frame which is adjustable thus making it possible to shift the
weight carrying portions with relationship to the rest of the frame
enabling placement of the weight at different portions on the body
or on different portions within the frame for persons having
different statures.
As will hereinafter be more specifically described this combination
of features results in a pack frame which is extremely versatile
and adjustable in that it will fit a variety of human shapes as
well as allow an infinite amount of variation as to the placement
of the load within the frame itself.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a pictorial representation of the pack frame including
the pack itself located upon the inventive frame structure.
FIG. 2 is an exploded view of the frame structure showing the
various parts in greater detail.
FIG. 3 is an enlarged portion of the connection between the
shoulder straps and the frame structure.
FIG. 4 is a pictorial representation of the means by which the pack
sack is suspended from the frame.
FIG. 5 is a sectional view looking downwardly on the frame more
particularly illustrating the means for holding the frame side
rails in position.
FIG. 6 is an enlarged portion showing one of the side pockets
having a double zipper combination hereinafter described.
DETAILED DESCRIPTION OF THE DRAWINGS
The pack frame is preferably fabricated from aluminum bar stock and
has a pair of side bars 21--21 connected at the top by an inverted
U-shaped top bar 22 and at the bottom by a rearwardly arched shelf
bar 23. At its end the top bar 22 is formed with necked portions
22a to fit into the upper ends of the side bars and is retained by
pins 24 passing through mating holes in the side bars and necks
22a. Detachable keeper rings 25 pass through terminal holes in the
pins 24. The shelf bar 23 can be made integral with the side bars
as illustrated or can be a separate member which is necked to
interfit with the lower ends of the side bars in the same manner as
the connection of the top bar 22.
The pack frame is further cross-braced by stationary cross-bars
26-27 and an adjustable cross-bar 28 located on upper straight
sections 21a of the side bars which extend about half of the length
of the side bars. At the lower ends of these straight sections the
side bars 21 bend forwardly at the approximate location of the
cross-bar 26 providing a rearwardly sloped center section 21b and
then bend forwardly at the approximate location of the cross-bar 27
providing a bottom section 21c which forms an obtuse angle with the
center section 21b which is slightly greater than the obtuse angle
at the juncture of the upper and intermediate sections 21a-21b. A
pair of two adjustable socket blocks 29 and two pairs of stationary
socket blocks 30 are sleeved on the side bars 21, the blocks 30
being staked at 31 to hold them in position. Each of the blocks 30
has a vertical through bore 30a for receiving the side bars and a
horizontal cross-bore 30b extending from its inner side face to the
vertical bore to serve as a retaining socket for a respective end
of one of the cross-bars 26-27. Similarly, the adjustable blocks 29
have a vertical through-bore 29a and a horizontal socket bore 29b
for holding the ends of the cross-bar 28. In addition, the block 29
has a second horizontal bore 29c which is threaded to receive a set
screw 32 for engaging the respective side bar 21. In this manner
the blocks 29 with the cross-bar 28 are locked relative to the pack
frame in selected vertical position.
It will be noted that the three intermediate cross-bars of the
frame are arched rearwardly in progressively greater amounts
starting with the adjustable bar 28 and continuing downwardly with
the stationary bars 26 and 27 so as to allow for lateral curvature
of the packer's back. The end portions of the cross-bars are
straight to fit into the sockets of the blocks 29-30, and are held
in sockets by the top and bottom bars 22-23 and by a pair of back
pad assemblies 33-34 to be later described.
In the production of the pack frame components the four sockets
blocks 30 are sleeved onto the length of tubular bar stock for
forming the side bars 21 and shelf bar 23, and are staked into
proper position before the bends in the side bar are formed. The
adjustable blocks 29 are then sleeved into the straight portions
21a and the side bars are sprung apart sufficiently to insert the
ends of the cross-bars 26-27 into the sockets 30b and the cross-bar
28 into the sockets 29b. Following this the top bar 22 is fitted by
its necked ends 22a, the upper ends of the side bars 21 and the
locking pins 24 and keepers 25 are applied.
Attention is now directed to a pair of shoulder strap assemblies 40
each of which comprise an intermediate shoulder pad 41 and front
and back strap extensions 42-43 from the pad which include
respective buckles 42a-43a for adjusting their effective length.
The lower strap components of the strap units 42-43 have respective
terminal grommets 44-45 which are sleeved on opposite end portions
of a respective pin 46 passing laterally through the lower end
portion of the corresponding side bar 21 and having a detachable
keeper ring 47. At its upper end each shoulder pad has a tab
extension 48 with a grommet 50 cooperating with a grommet 51
provided at the top of the upper strap component of the front strap
assembly 43. The two sets of these grommets 50-51 are sleeved on a
pair of pins 52 depending from the adjustable cross-bar 28 in
respective positions equally spaced from the side bars 21. Two or
more sets of vertical holes 53 for the pins 52 are provided in the
cross-bar 28 so that the lateral spacing of the shoulder pads 41
can be adjusted. The pins 52 are held at the top by keeper rings 54
and are free to swivel in the holes 53 so that the shoulder pads
are free to turn at the top relative to the pack frame to adjust to
the hiker's shoulder contour.
It is of importance to note that the pins 52 (see FIG. 3) are
purposely long enough to give "play" between the grommets 50-51 and
the underside of the adjustable cross-bar 28, and that the grommets
50 are underneath the grommets 51. This arrangement causes the
front and back strap units 42-43, when properly adjusted as to
effective length, to be equally tensioned by the weight of the pack
bearing down on the shoulder strap assemblies at the location of
the lower pins 46 and prevents vertical load from being transmitted
from the cross-bar 28 to the shoulder pads 41. To elaborate, again
referring to FIG. 3 when the front strap units 42 are tensioned
respective to pack load bearing down on the lower grommets 44
through the pins 46, the upper grommets 50 tend to walk slightly
down the pins 52. As they do so, the grommets 50 engage the
underside of the grommets 51 and cause them to move in concert and
equally tension the rear strap units 43. The pins 52 are long
enough so that when the strap units 42--42 are properly adjusted by
use of the buckles 42a-43a, the grommets 51 remain spaced below the
adjustable cross-bar 28. As a result, normally none of the weight
of the pack is carried from the cross-bar 28 downwardly against the
rear end of the shoulder pad 41. Instead, the vertical load on the
tab extension 48 of the shoulder pad is obtained from tension on
the rear strap unit 43. In that respect it is just as if the tab 48
were integral with the upper component of the strap assembly 43.
The described arrangement has the added advantage that the shoulder
pads 41 are free to turn relative to the pack frame as before
mentioned.
The principal functions of the pins 52 in addition to permitting
the aforesaid turning of the shoulder pads, is to hold the upper
portion of the pack frame in against the back of the hiker and to
prevent the pack frame from shifting laterally or twisting relative
to the hiker.
The vertical adjustability of the blocks 29 which hold the
cross-bar 28 is advantageous in obtaining maximum comfort and fit
for the particular hiker using the pack. Ideally, the lower pins 46
should be located at the smallest part of the waist and the
adjustable cross-bar 28 should be at the shoulder level. This can
be readily accomplished by freeing the upper pins 52 from the
cross-bar 28 but leaving them in the grommets 50-51, adjusting the
effective lengths of the shoulder straps by use of the buckles
42a-43a until the pack frame is at the proper level, raising or
lowering the bar 28 until it is at the level of the upper portion
of the pins 52, and then inserting the pins through the proper set
of the holes 53 determined by the neck size of the hiker and
applying the keepers 54.
The back pad units 33-34 (See FIG. 5) each comprise an elongated
pad 60 extending the width of the pack frame and strap extensions
61-62 with a buckle 63 for tensioning the pad. These straps pass
around the side bars 21 and are cinched at the back of the frame.
The pad units are vertically adjustable relative to the pack frame
to fit the hiker's comfort, and normally are positioned
approximately in the positions illustrated in the drawings. The pad
components 60 may comprise fabric envelopes filled with plastic
foam or other suitable padding material, but it is intended that
the word "pad" shall also include open-mesh, elastic and other
suitable relatively thin unfilled materials which will readily
contour to the hiker's back.
It is preferred that the pack be equipped with a waistband assembly
70 which will transfer much of the load of the pack to the hiker's
hips. This unit may be connected to the pack frame by grommets 71
which are also sleeved into the outer ends of the pins 46 which
hold the lower ends of the shoulder strap assemblies 40. These
grommets 71 are located in strap extensions 73 of a back pad 72.
The material of these extensions continued from the ends of the
back pad 72 to form extension loops 74 which retain buckles 75 for
receiving rear belt extensions 76 of a pair of hip pads 77 which
have front belt extensions 78. One of the latter is connected to a
suitable belt buckle 79. In effect, the back pad 72, extension
loops 74, buckles 75, rear belt extensions 76, hip pads 77, and
front belt extensions 78 comprise a continuous waistband having
adjustable hip pad locations and arranged to be cinched at the
front. When properly adjusted this waistband carrier a major part
of the weight of the pack by the extensions 73 which connect to the
lower end portion of the pack frame by the pins 46 and grommets 71.
The rest of the weight is carried by the shoulder strap assemblies
40 by downward pull exerted by the pack on the front and back
shoulder strap units 42-43 via the pins 46 and grommets 44-45.
As another part of the present invention an adjustable U-shaped
supporting bar 80 is provided which is mounted on the side bars 21
by a pair of slide blocks 29' which are of the same construction as
the adjustable socket blocks 29, except that they are also formed
with a horizontal pin opening 81 which crosses the socket bore 29b'
for receiving a locking pin 82 having a keeper 83. The blocks 29'
are turned a 90.degree. relative to the blocks 29 so as to face the
socket bores 29b' toward the rear for receiving the ends of the bar
80. These ends are laterally bored to mate with the holes 81 and
receive the locking pins 82.
The pack sack 80 (See FIG. 4) for use with the described packboard
is provided at the top with a sleeve 91 open at its end to the back
of the pack sack and extending from these open ends along the
lateral sides of the pack sack and along the front side thereof.
The width of the sleeve 91 is sufficient to permit the U-shaped bar
80 to be threaded therethrough when it is detached from the pack
frame and then the bar 80 and pack sack as a unit are secured to
the pack frame by inserting the ends of the bar into the sockets
29b' of the slide blocks 29' and inserting the locking pins 82 and
related keepers 83.
Near its lower rear corners (See FIG. 1) the pack sack 90 is
provided with a pair of straps 92 having buckles 93. These straps
are arranged to be passed and secured around the side rails 21 to
hold the lower part of the pack sack against the pack frame and are
slidable along the side rails to conform with vertical adjustment
of the blocks 29' to achieve the desired height of the pack sack
relative to the pack frame to suit the hiker.
Reference again being had to FIG. 4, the upper wall 94 of the pack
sack 90 is recessed and surrounded on three sides by the sleeve 91
and at the back by the flap 95 which is an upward continuation of
the back wall 96 of the pack sack. This flap is made wider than the
back wall 96 and substantially longer than the front-to-back width
of the upper wall 94 so that a jacket or other objects can be
conveniently stored in the tray created by the upper wall 94 as the
tray bottom and the sleeve 91 and lower back portion of the flap 95
as the four side walls of the tray. The flap 95 is provided with
tie strings 97 at its front corners which can be secured to anchor
loops 98 provided on the sides of the pack sack after the flap has
been pulled over the top of the tray to protect the stored object
from the weather and hold it in storage position. The rear corners
of the flap are preferably sewn to the back edges of the pack sack
as at 99 below the mouths of the sleeve 91 so that the pull lines
of the tie strings 97 will be such as to keep the longitudinal side
edge portions of the flap over the lateral sides of the tray.
The rest of the compartition of the pack sack can be selected to
fit particular needs. Commonly, there will be two major pockets
open to the front of the pack sack and several side pockets, all
with zipper closures. The lower end of the pack sack is spaced
above the lower shelf bar 23 providing storage space which is
commonly used for a sleeping bag.
It is to be noted that for convenience of the user the pockets may
well have double acting zippers such that they may easily be opened
from either end, in the middle or anywhere in between without
disturbing the contents. This convenience is available by providing
a zipper for the entire opening having a chain of teeth extend
along each edge and a pair of oppositely facing sliders mounted
thereon such that when the sliders are adjacent each other the
opening is closed. Referring to FIG. 4 it can be seen that the two
sliders 100 completely close the chains of teeth 102 thus closing
one of the main pockets. FIG. 6 illustrates the application of the
opposed sliders 104 to a side pocket 106. It is to be noted that
the pocket further includes a flap 108 to make the compartment
weather tight.
* * * * *