B ody part supporting platform device The present invention relates to a platform device, for example a chair seat, chair back, backboard, or footboard, or a platform constructed as a backboard or bench, intended for body part support for a person, and equipped with an instability function for strengthening and stimulating the person's muscles and sense of balance. The use of such a device is especially related to the principle of controlled exercise by having to balance and control instability during physical exertion.

The invention represents a new way of providing a user with the possibility of movement and activity of muscles in the abdominal and back regions and generally along the whole spinal column when the person is in a sitting or lying position. The invention could be used on existing or new chairs or seats or exercise apparatus, also including chairs and seats for office or home use, or in means of transport such as cars, buses, trains, planes, boats and so forth, and in connection with exercises for a user in a standing position.

Nowadays it is a problem that more and more people have sedentary occupations. We have comfortable chairs which are basically supposed to support the body, but which more often than not help to cause back problems. This is usually a result of little physical activity, which means that the supporting muscles are not maintained, but are debilitated PCT specification W002/05697 describes an exercise apparatus primarily intended to have a training effect on all muscles and tendons surrounding the muscle groups that are the main focus of the exercise. The embodiments in this document are also related to the principle of controlled exercise by having to balance and control instability during physical exertion. The document describes, among other things, an exercise bench primarily for strengthening a person's abdominal muscles, but where the embodiment can be set to be unstable so that the user experiences an effect on all surrounding muscles.

As previously known, exercise under controlled instability has positive health effects on a person's muscles, tendons and balance in the case of both strength training and rehabilitation after injury. It is important that the degree of movement for the devices that provide instability in the exercise apparatus should be easily adjustable, and that this adjustment is stepless from a lockable position. This will spare a first-time user from experiencing a movement of the exercise apparatus for which the user is unprepared.

The earlier solutions for instability of exercise and sports equipment have limited areas of application. The invention will provide a user with a simple way of adjusting instability of a platform irrespective of the context in which the platform is used.

The present invention seeks to solve the problem of how instability can, in a new and simple manner, be implemented for use with, for example, seats, benches and standing platforms. The invention will provide a user with a simple way of adjusting instability of a body part supporting platform irrespective of the situation in which the platform is used.

According to the invention, the device is characterised primarily in that it has a mechanism which permits adjustment of the platform from a fixed position to a tiltably movable position that is unstable in a plurality of directions, that the centre of the platform is movably secured via a ball joint to a fixed underlying part, that between the platform and the fixed underlying part, and around the centre of the platform and the ball joint there is provided at least one annular or tubular air chamber formed of an elastically yielding material for retaining air pressure, and that the air chamber is connected to means for adjusting the air pressure in order to adjust the platform's degree of stability.

According to one modification, where the platform is specifically a backboard or a bench, the device is characterised in that it has a mechanism which permits adjustment of the platform from a fixed position to a movable, unstable sideways tilting position, that the platform is supported so as to be tiltably movable sideways on a fixed underlying part, that between the underside of the platform and the fixed underlying part there is provided at least one tubular air chamber formed of an elastically yielding material for retaining air pressure, and that the air chamber is connected to means for adjusting the air pressure in order to adjust the platform's degree of stability.

Further embodiments of the device are apparent from subsidiary claims 2-6.

The invention will now be described in more detail with reference to the attached drawings.

Figs. 1 a and 1b are drawings of a device including a platform provided with an instability function.

Figs. 2a and 2b are a plan view and a sectional view of the device including a platform provided with an instability function.

Figs. 3a and 3b show a locking function for a device including a platform provided with an instability function.

Fig. 4 shows an office chair with a seat and back provided with an instability function.

Figs. 5a-5c show an exercise apparatus in the form of a bench provided with an instability function.

Figs. 6a-6c show areas of application for an exercise apparatus in the form of a bench provided with an instability function.

A platform or a seat 1 is movably secured relative to a board or a fixed part 2, as can be seen in Fig. 1. The platform 1 and the board 2 are connected via a ball joint consisting of a ball head 3 and a socket 4 that are clearly shown in Fig. 2a. Disposed between the platform and the board is an air chamber formed of a ring or a tube 5 made of an elastically yielding material intended to retain air under pressure. The chamber in the illustrated embodiment is annular and located centrally around the ball joint 3,4. The air chamber is connected to means for adjusting the air pressure. Figure 1 shows a hand pump 7 connected to the tube. The platform will be tiltably movable in a plurality of directions about the ball 3 as indicated by arrows 10. The supply of air to the air chamber of the ring or tube 5, which thus increases the pressure on the underside of the platform, will result in a reduction of the platform's degree of motion. The degree of motion is thus dependent upon the pressure from the tube. High pressure will thus wholly or partly prevent movement of the platform.

Adjustment of pressure can be effected using a hand pump 7, as shown in Figs. 1 and 2, or by the tube being connected to an electrically operated pump that is known per se (not shown).

Figure 3 shows a locking mechanism for a platform as shown in connection with Figures 1 and 2. Fastened to the board 2 on two of its sides there may be, for example, a piece of fabric, a mat or a plate 8, 8', which has means for attachment to the platform or said seat 1. A means for attachment will, in the case of a piece of fabric or a mat 8, expediently be made of a hook-and-loop fastener 9,9'. If a plate is used, grooves, loops or the like would be suitable. The illustrated locking means outlined in Figure 3 merely serves as a non-limiting example to show that the embodiment has means for locking the platform independently of the pressure in the tube.

When the invention is used in, for example, an office chair, the user will be able to set a desired degree of instability. By sitting and compensating for the instability of the seat, the user will manage to constantly stimulate muscles of the abdomen/back/upper part of the body.

Figure 4 shows a typical office chair with built-in mechanism for instability of a chair seat 13. Between a seat frame 12 and the seat 13 there is provided is a ring or tube 14 of an elastically yielding material in order to form an air chamber, as shown in connection with Figs. 1 and 2. A hand pump 15 is also shown for adjusting the possible tilting motion of the seat 13. The hand pump could easily be replaced by a switch or lever which gives signals to an electromotor for control of an air pump (not shown). Levers 17,18 are present to enable adjustment of respectively the height of the chair and the angle of the seat frame 12 and back rest 19. If the invention is used for the installation of said platform inside a back support, as shown by the reference numeral 16, a person or the user will, by using a pump 15', be able to adjust the degree of freedom of the back as regards tiltability and thus obtain a sitting position that is unstable for both back and seat for the strengthening of his buttocks, back and general balance.

Figure 5 shows an exercise apparatus in the form of a bench where an upper part 20 normally forms a surface on which the user lies or sits. The upper part, which we can call bench top 20, is tiltable about bearings 22, 22'which join the upper part to the bottom and frame 24. The tilting motion, as indicated by arrow 25, runs transverse to the tilting axis of the part 20 which extends through the bearings 22,22'. Disposed between the bench top and the bottom is at least one body 27 that is made to contain air under pressure. Connected to the body 27 is a pump 28 with accompanying valve (s) for adjusting the pressure. The pump may be of the type hand pump, foot-assisted pump, electrically assisted pump or other known type of pump for the supply of air pressure. It will be understood from what has been explained above in connection with Figs. 1-4, that the degree of air pressure will determine the degree of movement and the extent of tilt the bench top will be able to perform.

In connection with a platform and bench as described above where an electric pump is optionally connected to the system for regulating air pressure, it would be natural to position sensors on the top of the platform and bench so as to be able to send signals to the electric pump. It is an advantage that such equipment, which is described herein and which is equipped with an instability function, should be capable of being used in a manner that is safe for the user, in particular if the user is unfamiliar with the equipment. Sensors placed in the top of the equipment, the seat and back of a chair, the surface of a bench top on which the user lies, and so on will give signals ensuring that the equipment is set in a fixed and neutral position after use. The device according to the invention equipped with an electromotor-driven pump for air pressure will then be in a fixed and stable position for the user when the user for the first time comes into contact with a surface or top of the equipment. Sensors are indicated by the reference numerals 31-31"', 32-32"'and 33,33'in Figures 4 and 5 respectively.

Fastened to the bench top 20 are two handles 30-30', the use of which will be explained in connection with Fig. 6.

The exercise apparatus as described in connection with Fig. 5 has several areas of application. The bench top may be fixed or tiltable according to the user's wishes. The user will be able to adjust the degree of motion steplessly by using an air pump for desired air pressure. The exercise apparatus can be used for strengthening the abdominal muscles by doing so-called sit-ups (Fig. 6a), back exercises (Fig. 6b) and for building up the arms and upper part of the body by doing push-ups (Fig. 6c), the handles during such push-ups being gripped by the user. By having the bench set to be tiltable and unstable, the muscles around the primary muscle groups that it was intended to strengthen will, during all the said exercises, experience a training effect. In addition, the user's sense of balance will be stimulated during such exercise.

Both the platform in the form of a tilting seat, as described in connection with Figs. 1 and 2, and the exercise apparatus, as described in Fig. 5, could be used for balance exercises by the user standing with his feet on such a platform and optionally performing various exercises. This is not described in more detail here as such use will be obvious to a person skilled in the art in the light of what is otherwise described and illustrated.

The solutions that are described herein will have a positive effect on many muscle groups for a person using the device, and at the same time will also have a positive effect on the user's balance and thus his muscle control.