TITLE
Insert, for a-, head restraint in a vehicle seat and a head restraint with such an insert —
TECHNICALFIELD
The present invention relates to an energy absorbent insert for a headrest in a vehicle seat. The insert has a first main surface which, when installed in a headrest, will face the back of a user's head, and comprises a number of plane elements with a first and a second main surface, and at least a first and a second edge around said main surfaces.
BACKGROUND ART
In traffic accidents, damage to the head and/or spinal columns of the driver and passengers is common. Such injuries are often caused by the head of the injured person lashing backwards during the accident, and, in a way which causes injuries, hitting a headrest arranged on the vehicle seat. There are a large number of known designs to counteract such injuries, which aim at absorbing the energy from a head in case of a traffic accident. However, a common drawback of such known solutions is that the energy which they absorb is often returned to the head, which, as such, can cause injuries.
SUMMARY OF THE INVENTION
There is thus a need for a headrest in a vehicle seat which absorbs energy from a head without returning the energy to the head.
This need is addressed by the present invention in that it discloses an energy absorbent insert for a headrest in a vehicle seat.
The insert according to the invention has a first main surface, which, when installed in a headrest, will face the back of the user's head, and comprises a number of plain elements with a first and a second main surface, and at least a first and a second edge around said main surfaces.
The plane elements are arranged in the insert with their first or second edge towards the main surface of the insert.
Suitably, but not necessarily, the insert also comprises a frame around at least part of the insert, where the frame protrudes outside of the rest of the insert and a number of the plane elements are attached to the frame.
In a way which will become apparent in the following detailed description, the design according to the invention with plane elements arranged on edge with the edge towards the user will make it possible for the insert to absorb the energy, and "eat the energy" by means of the elements being deformed or breaking. Since they are deformed or will break, the elements will not be able to return any energy to the head of the user, they will only be able to absorb energy.
One of the reasons for why the invention discloses an insert for a headrest is realized here: parts which can break in case of an accident should be possi- ble to exchange as simply as possible, which makes it more suitable with an insert than with a design which is permanently attached to the headrest.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will be described in more detail below with reference to the ap¬ pended drawings in which:
Fig. 1 shows an upholstered headrest for a vehicle seat with an insert according to the invention, and
Fig. 2 shows a headrest prepared for an insert according to the invention, and
Fig. 3 shows examples of elements for designing the insert according to the invention, and
Figs. 4a and 4b show examples of an insert according to the invention, and
Figs. 5, 6 and 7 show examples of alternative embodiments of the elements of Fig. 4.
EMBODIMENTS
Fig. 1 shows, for reasons of comprehension, a headrest 100 with an insert according to the invention. Over the insert there is arranged, for example, comfort foam and upholstery of fabric, which causes the insert according to the invention to not be visible in the headrest in Fig. 1. The insert is, however, intended to be arranged in a recess in the headrest in such a way that a main surface of the insert will be facing the head of an intended user, something which will become apparent in the continued description.
The headrest 100 is intended for a vehicle seat in which the headrest is ar¬ ranged, for example, by means of two legs, 110, 112 which protrude from the headrest and which can be attached to the vehicle seat, suitably in its upper edge.
Fig. 2a and 2b show the headrest 100 of Fig. 1 in a front view and a side sec¬ tion view respectively but with the insert and the upholstery of the insert re¬ moved. Due to this, it can be seen that the insert is intended to be designed for being arranged in a recess 205 in the headrest which then has a shape which essentially corresponds to the upper shape of the insert.
The outer shape of the insert, and thus the shape of the recess 205 in the headrest, can be varied in a number of various ways but common to these different ways is that they should be such that they can be arranged in the headrest in such a way that energy from a head can be absorbed in case of a traffic accident. The shape of the insert which is shown in Fig. 2 is rectangu- lar but other shapes can also be imagined for example circular or oval. The size of the insert is designed keeping in mind an assumed size and position of a head, and to a certain extent also keeping in mind the energy which it is desired to absorb but suitable examples of measurements is that the height of the insert should be approximately 80-90 % of the height of the headrest,
and the width of the insert is suitably at least approximately 70 mm for the front seats and at least 105 mm for the rear seats.
The insert according to the invention is designed by means of elements, where a general principle is that the elements are plane, and are arranged in the insert so that they are on edge towards the user.
Another way of expressing the principle of the elements and their orientation in the insert is that the elements are plane, in other words they have a first and a second main surface and at least a first and a second edge around these main surfaces. The plane elements are arranged in the insert with the first or the second edge towards a first main surface in the insert.
Fig. 3 shows examples of two such elements 302, 304 shaped as plane rec¬ tangular plates, but a number of other possibilities can be imagined, which will be shown later in this description. The plates have a first edge 302', 304' and a second edge 302", 304" which is constituted by the side edges of the longside of each plate. The plates additionally have a first and a second main edge where only the first main edge 305, 307 is visible in Fig. 3.
In the insert the plates will be arranged so that their first edges 302', 304' face the head of an imagined user - in other words the plates are on edge towards the user.
In order to obtain this orientation with the plane plates 302, 304 each element comprises a recess or a notch 311, 312, the function of which will become evident later. It should also be pointed out that the plane rectangular plates are only one version of the elements according to the invention, other possi¬ bilities will be shown later on in this text.
In Fig. 4a an insert 400 according to the invention is shown. As can be seen, the insert comprises a frame 450 which extends around the entire or a main part of the insert, and in which the plane elements can be attached. The ele¬ ments can be arranged in a large number of various ways in the frame, but in
a preferred embodiment they are arranged so that they form a "honeycomb" structure, in other words there is a first group of plates which in similarity to those in Fig. 3 extended in parallel to each other, and which cross a second number of plates which extend parallel to each other at a crossing angle which is approximately ninety degrees. The edges 302', 304' thus point to¬ wards the head of an imagine user.
By means of Fig. 4a the function of the notches or slits 311, 312 which the elements 302, 304 in Fig. 3 are provided with will be realized: when the ele¬ ments are arranged in the insert they are arranged in such a way that the openings 311, 312 in the slits of two crossing elements end up facing each other, so that the elements can be arranged in one another. In other words, the opening in one slit will point towards the user, and the corresponding opening in the slit in a crossing element will point inwards in the in¬ sert/headrest.
A headrest with the insert according to the invention is intended to absorb energy in the case of traffic accidents better than previously known head¬ rests. The intention is that when a head in the case of a traffic accident hits the insert, a number of the elements will break or at least be severely de¬ formed, which will cause extremely small amounts of energy or no energy at all to be returned to a head which hits the insert in case of a traffic accident.
Instead of the energy being returned to the head, which will cause the head to snap forwards again, the collision between the head and the headrest will be "mute", where the collision energy of the head will be used to deform or break the elements at the same time as the deformed or broken elements cannot return significant amounts of energy to the head.
Suitable materials for the elements in the insert are plastic, wooden fibre, carton or metal foil or alternatively a hybrid material which is designed as a combination of the mentioned materials. The exact dimensions of the ele¬ ments with regard to for example thickness, height, width etc. are decided
experimentally, and depend on a number of factors such as the chosen ma¬ terial and the amount of energy which is believed to be involved in a traffic accident or another event where it is desired for the headrest to have the de¬ sired energy absorbent function.
The elements are attached as has been mentioned suitably to the frame 450, preferably by means of gluing or welding if the material so allows, which is the case with for example plastic materials.
With renewed reference to the complete headrest of Fig. 1 : the insert 400 is attached to the recess 205 in the headrest, suitably by means of the frame 450 of the insert being attached, for example by means of gluing or snapping, to a corresponding edge in connection to the recess 205 of the headrest.
Over the insert, there is then suitably arranged a covering plate for example in the same material as the elements 302, 304, which has as its function to hide the elements and to offer a smooth surface which can distribute the en- ergy over the elements of the insert when a head hits the insert in the case of a traffic accident.
Fig. 4b shows the insert 400 of Fig. 4a in a headrest 100 in a way which makes it even more evident how the insert is intended to be arranged in the headrest.
Above, the elements have been described as being constituted by plates which are on edge in the insert. This is however only one possibility regard¬ ing the shape of the elements for an insert according to the invention. In Fig 5 other examples are shown, such as cylindrical 510 and rectangular 520 rods which are hollow. These rods are formed by a plate which has been folded or rolled in order to achieve the desired shape. Other examples of elements which can be used are hexagonal elements or semicircular elements. It will here be realized why the text consistently has spoken of plane elements, of which flat elements are only one example: the elements in Fig. 5 and a large amount of other examples are constituted by elements which can be said to
be plane in one way but which are not flat. However the elements 510, 520 also have a first 502 and a second 504 edge which delimit a (cylindrical shape) or several (rectangular shape) main surface.
Fig. 6 shows examples of how the elements 510, 520 could be arranged in an insert according to the invention: for the sake of clarity, the inserts are shown only with four elements, but it will be realized that this is only an ex¬ ample of the number of elements. In the cases which are shown in Figs. 5 and 6, the elements are constituted by closed geometrical shapes, which means that they can be arranged side by side in the insert, for example by being glued to the frame and to each other.
Fig. 7 shows still another embodiment 700 of the invention: in this example, the elements in the insert are cone shaped with the one end of the cone fac¬ ing the head of an intended driver. In this embodiment as well, the elements are suitably arranged in a grid pattern, in other words in a pattern of regular rows and columns. The cones can possibly be truncated which is the em¬ bodiment shown in Fig. 7.
In the case of an accident, one or more of the cones will collapse inwards in the insert due to the collision energy of the head, so that the desired energy absorption takes place.
The invention is not limited to the above described examples of embodi¬ ments, but can freely be varied within the scope of the appended claims.
For example, the angle which the plane elements are arranged in towards the user can be different from that which has been shown in the drawings, in other words a straight angle. The angle which is intended here is, in the case of plane plates, an angle between the first or second main surface of the plate and an intended direction which goes perpendicularly into the insert. Suitable angular intervals are in that case 45-90 degrees, where 90 degrees is that which has been shown in Figs. 4 and 6. In the case of, for example,
cones as elements, the angle which is intended is the angle between said imagined direction and a vertical line which goes straight into the cone.