WO2005117641A1

WO2005117641A1 - Backpack frame

Info

Publication number: WO2005117641A1
Application number: PCT/EP2005/005914
Authority: WO
Inventors: Kevin Byrd Murray
Original assignee: Mammut Sports Group Ag
Priority date: 2004-06-04
Filing date: 2005-06-02
Publication date: 2005-12-15

Abstract

The invention relates to a frame (1) for supporting a container to be carried on an individual's back, wherein the frame is twistable to correspond to natural body twisting, particularly to body twisting in the thoracic spine area of a said individual's back. In a preferred embodiment the frame has a butterfly shape. The invention further relates to containers, particularly backpacks, comprising or being mounted to a said frame.

Description

BACKPACK FRAME

FIELD OF INVENTION

This invention concerns a rucksack-type equipment for carrying loads on the back. In particular it concerns a backpack with a stiff internally fitted frame intended, inter alia, for hiking, mountaineering and other outdoor activities.

TECHNICAL BACKGROUND

From the very earliest days, backpacks have had frames. External frames usually consist of several parts forming a framework of horizontal and vertical pieces. The earliest frames were wooden. From the First World War, external steel frames were used for military packs. In the 1960s external frames from aluminium tube became popular. From the 1970s, climbing and mountaineering backpacks usually had an internal frame.

External Pack Frames

An external pack-frame is defined as a framework which is carried by means of shoulder straps on one side and upon which the load is attached to the other side. Sometimes the load is directly fastened to the pack frame, more frequently a bag is attached to the frame.

Figures 1A and B show the backpack frame used by the prehistoric traveller Oetzi (circa 3500 BC). This consisted of a nearly 2 m long hazel rod bent into a U-shape and two narrow wooden slats. Other artefacts found at the site suggest that a leather bag was fastened onto the carrying frame. This frame is approximately 65 cm long.

In the 1890s, the Gold Rush in Yukon and Alaska lead to the commercial development of external frames for backpacks. The frames consisted of two vertical wooden bars with horizontal cross pieces. The length of the vertical members was typically between 75 cm and 100 cm. Leather shoulder straps were attached to the horizontal wooden pieces. Figure 2A shows the layout of such a frame.

Very bulky and heavy loads can be carried using this kind of pack frame. This design was the dominant form for large load carrying backpacks the next fifty years. Figure 2B shows a photograph of a 1940s Swiss Army backpack frame.

Trapezium form frame

A tall pack frame is not suitable in combat as it is unstable when running and also prevents the soldier from firing a rifle in a prone position. Around the time of the 1914-1918 war, backpacks with tubular A form steel frames and cotton canvas bags were issued to military personnel. These frames were much shorter than previous designs as they only stretched from the shoulders to the waist of the soldier (approx 50 cm). The pack attached to this frame was much smaller than could be attached to a pack frame. (Figure 3)

Before 1930, wooden frames with leather straps were commonest materials. The bags themselves were usually made of leather. Occasionally cotton canvas or loden (a heavy wool fabric) was also used.

In the 1950s, military designers changed the materials for pack frames to aluminium alloy for lighter weight. Figure 4 shows an aluminium frame from a US Army Alice pack, designed in the 1950s.

In the late 1960s, aluminium pack frames became popular for outdoor sportsmen. These remained popular in and outside the USA until today for camping and backpacking. Figure 5 shows a typical external aluminium pack frame. Here, the horizontal tubes are curved to wrap around the users back.

Internal Frames

During the 1970s, mountaineers looked for lighter and more stable solutions. The preferred designs for mountaineering packs became nylon bags with internal frames. Internal tube frames were most usually a very simple inverted U shape. These frames are constructed using 6063 aluminium tubing in various diameters from 12mm to 18mm. High strength 7075 aluminium can be used to make smaller diameter frames from 8mm to 10mm (Figure 6)

Other internal frames are simple bars of aluminium, plastic or steel inserted into the pack in parallel form (Figure 7). Most products use flat 20mm bar or flat 25mm bar from 6061 aluminium. Smaller section bars can be made with 7000 series aluminium alloys. Moulded nylon, glass fibre and carbon fibre bars have also been used. The horizontal stiffness is occasionally provided by an additional member, but often the stiffness of the foam and fabric is sufficient. Occasionally bars are riveted together to form H or trapezium forms.

Typically, internal frames have an S curve in side elevation to match the curvature of the spine (Figure 8)

In the mid 1980s moulded plastic frames were created which mimicked the function of the trapezium frame. (Figure 9)

Another layout of internal frame is the X form (Figure 10). The X frame was a design from The North Face from the 1970s. It is also used by Millet, Tatonka and others.

Movement

From the 1980s, considerable development has been focussed on the movement of the back and the hips during walking. There are several patented solutions in this area but all relate to providing a pivot to allow the hip-belt to rotate to accommodate movement of the hips during walking. (Figure 11 )

When climbing, other movements become important. The shoulders twist forwards relative to the hips. This twisting occurs in the centre of the back in the thoracic spine area. (Figure 12 and Figure 13). Accordingly, the present invention (Figures 14, 15 and 16) concerns a frame which accommodates this movement.

BRIEF DESCRIPTION OF THE FIGURES

Figs.1 A and B show a prehistoric backpack frame.

Fig.2 A shows a frame with two vertical bars and horizontal cross pieces.

Fig.2 B shows a military backpack frame of the 1940s.

Fig.3 shows a trapezium form backpack frame. Fig.4 shows a military aluminum pack frame from the 1950s.

Fig.5 shows a typical external aluminium pack frame of the late 1960s.

Fig.6 shows an internal tube frame of the 1970s.

Fig.7 shows another internal tube frame consisting of two vertical bars.

Fig.8 shows an S-curved frame in side view. Fig.9 shows another variant of the trapezium frame.

Fig.10 shows an X-shaped frame.

Fig.11 shows a frame providing a pivot for the hip-belt.

Fig.12 demonstrates a twisting movement of the upper body.

Fig.13 shows a human's spine in side view. 1 = cervical spine (neck); 2 = thoracic spine (middle back); 3 = lumbar spine (lower back).

Figs.14 A and B show a butterfly-shaped frame in front-view and side-view.

Figs.15 A and B show twisting movements of a butterfly-shaped frame.

Fig.16 shows typical application of butterfly frame to a sports backpack.

DESCRIPTION OF THE INVENTION

The present invention relates to a frame construction for supporting a container to be carried on a human individual's back.

In one embodiment, the invention relates to a frame which is internally mounted into a backpack, particularly into a climbing or mountaineering backpack. The underlying concept of the frame construction is based on the twisting movement of the spine and its incorporation into a backpack frame.

In another embodiment, the frame may be mounted to or incorporated into any container construction other than a backpack, intended for being carried on a human individual's back.

Recently, CNC machine bending and advances in strong aluminium alloys have made new variants of backpack frames possible. The advantage is that shapes which were previously too complicated to manufacture are now possible and hence new physiological benefits can be incorporated into these frames. Accordingly, the frame 1 of the present invention typically has the shape of four open loops 2a, 2b, 2c, 2d linked together at their ends in a four-leafed clover arrangement without any crossing parts or sections. It further comprises a longitudinal central section 3 separating the loops into two open loops 2a and 2b of an upper section 4 and two open loops 2c and 2d of a lower section 5 of the frame 1 , in an elevation view. The frame may be made of a single piece of a rod-like material bent into the four loops shape or may consist of two or four parts linked together at their ends by means of joints, pins or sleeves 6 to give said foor loops shape. The loops 2a - 2d may be of identical shape and size. Typically, however, the loops 2a and 2b of the upper section differ in shape and/or size from the loops 2c - 2d of the lower section 5 of the frame. The four loops construction of the frame according to the present invention not only prevents the cervical and lumbar spine sections of an individual from direct contact with the back-load or back pack and thus from possible restrictions in the movements of the spinal chord, but also allows for twisting of the frame in order to follow the movements of the carrier's back during walking or climbing, as depicted, for example, in Fig. 12.

In one embodiment of the invention, the frame is bent into the form of a butterfly with corner points to correspond to the carrier's back on one hand and to the container contruction on the other hand. Where the container is a backpack the corner points of the butterfly frame correspond to the four corners of the backpack back (Figure 14 A). In the elevation view, the shape is an S form to correspond to the curve of the spine (Figure 14 B).

In a preferred embodiment, the frame is made in two parts linked by tubing sleeves, e.g. aluminium tubing sleeves, in the midpoint. However, it is also envisaged according to the present invention that the frame is made in four parts linked via pins, joints, sleeves or the like, to give said butterfly shape.

These sleeves allow the upper and lower half to twist in a horizontal plane. This twisting of the frame corresponds to the twisting motion of the spine when climbing or walking. As the back moves, the shoulders twist relative to the hips.

This twisting of the spine comes from the thoracic vertebra in the centre of the back. The frame geometry is made to correspond to this motion. (Figure 15 and Figure 16)

Preferably, the frame shape according to the present invention has at least one of the following geometric features:

- The frame is constructed to support top of pack and load balance straps.

- The frame also supports bottom corner of pack and the hip-belt balance straps

- The shape is curved to avoid contact with the cervical spine. This also provides free movement when the head is tilted upwards.

- The shape is curved to avoid contact with the lumbar spine

- The frame has an S form in side profile which follows the curve of the spine. - The butterfly frame twists to follow the movement of the back. This twist motion corresponds to natural body twisting in thoracic spine area.

- The layout of the two links and the two upper and lower frame sections provides a spring mechanism whereby the frame returns to its original shape after twisting.

This frame is, by preference, constructed of 6061 aluminium rod of 6mm in diameter but can also be manufactured with tubing or rod of various diameters and materials. Alternative materials are, for instance, 6063 aluminium tubing from 9mm to 18 mm in diameter or 7075 aluminium tubing of 7 to 10mm diameter. If the frame is made from tubular material, the links can be external sleeves as on the rod version of the frame or pins fitted to the inner diameter of the tube.

While the frame according to the present invention may be particularly useful in backpack designs for outdoor sports like climbing, it may of course also be applied to any containers or container constructions carried on an individual's back including but not limited to oxygen bottles for divers or fire-fighters, bottles or other containers filled with chemicals such as dyes, varnishes, herbicides, insecticides, for spraying, or backpack-type containers used for other purposes including non-sports purposes such as manual collection of fruit, transportation of heavy loads to remote sites, transportation of heavy loads to or at hardly accessible or remote construction sites, and the like.

Where the container or container construction is flexible by itself, such as will be the case with a bag or a rucksack, it will smoothly follow the twisting motions of the frame mounted thereto. Where the container is rigid, it may be preferred that the frame further comprises fastening means for tightly, preferably reversibly, connecting the container to a longitudinal central section at or around the middle of the frame, while at the same time it may be advantageous that the corner points of the frame be not directly attached to the container. In that latter case the frame construction of the present invention will allow twisting movements of the body without substantially causing the container to move, while at all times the pressure of the loaded container exerted to the back of the individual will be distributed to a maximum back area. Consequently, such improved pressure distribution will contribute to relieve the individual from the development of painful local bruises. Also, the twistable frame of the present invention provides the carrier of the back container with more room to move.

The invention is further described in the claims, wherein facultative or preferred embodiments are defined by dependent claims.

Claims

CLAIMSWhat is claimed is

1. A frame (1 ) for supporting a container to be carried on an individual's back, characterized in that the frame (1) has the shape of four open loops (2a, 2b, 2c, 2d) linked together at their ends in a four-leafed clover arrangement without crossing parts, the frame being twistable to correspond to natural body twisting, particularly to body twisting in the thoracic spine area of a said individual's back.

2. The frame according to claim 1 , wherein it has a shape that is curved to avoid contact with either or both of the cervical spine and the lumbar spine.

3. The frame according to claim 1 or 2, wherein it comprises a longitudinal central section (3) separating, in an elevation view, the loops into two open loops (2a, 2b) of an upper section (4) and two open loops (2c, 2d) of a lower section (5).

4. The frame according to claim 3, wherein it comprises two frame sections (4, 5) linked together by pivoting links (6) allowing each section to twist in a horizontal plane in response to movements of the upper body.

5. The frame according to any one of claims 1 to 4, wherein it has a butterfly shape.

6. The frame according to claim 5, wherein the butterfly shape comprises four corners suitable for linking four corners of a said container.

7. The frame according to any one of claims 1 to 6, wherein the frame provides a spring mechanism whereby the frame returns to its original shape after twisting.

8. The frame according to any one of claims 1 to 7, which in an elevation view has an S curve in side profile.

9. The frame according to any one of claims 1 to 8, which is constructed with a metal, preferably aluminium, rod or tubing.

10. The frame according to any one of claims 1 to 9, wherein the container is a backpack.

11. The frame according to claim 10, which is mounted internally into a backpack by means of a pocket in a back panel of said backpack.

12. Use of a frame defined in any one of claims 1 to 11 , in the manufacture of a container to be carried on an individual's back, for supporting said container.

13. Use according to claim 12, wherein the container is a backpack.

14. Container to be carried on an individual's back, characterized in that it comprises or is mounted to a frame defined in any one of claims 1 to 11.

15. Container according to claim 13, which is a backpack.

16. Backpack comprising a frame defined in any one of claims 1 to 11.