This invention relates to exercise equipment and more particularly although not exclusively discloses improvements in rebound exercisers.

Rebound exercisers typically comprise a mat or webbing which is suspended within a circular frame by means of springs around the periphery thereof. The tension in the springs is preset so that the mat will resiliently support a person's weight in the manner of a trampoline. Such devices can therefore be conveniently used indoors for a wide variety of exercises such as for example jogging on the spot or sit-ups etc.

With existing exercisers however a number of disadvantages have been noted. Firstly as the outer ends of the coil springs are often simply hooked through holes drilled around the upper surface of the frame prolonged use causes these holes to wear into a elongated configuration. This reduces the pre-set tension on the mat. Also these earlier designs resulted in protrusions around the outer edge of the the exerciser which could be uncomfortable or ever dangerous to a user. Furthermore the springs when fitted in this manner are thought to generate the squeaking noise often observed in such devices and in addition are subject to premature failure due to the excessive stresses and flexing imposed on their end segments.

It is therefore an object of this invention to ameliorate the aforementioned disadvantages and accordingly this invention discloses a rebound exerciser in which the web or mat is suspended within a frame by spring means around the periphery thereof wherein said springs are shaped to reduce stress concentrations at the ends and engage wear resistant bearing means provided around the inside wall of the frame.

One preferred embodiment of this invention will now be

described with reference to the attached representations in which.

Figure 1 is a perspective view of one form of rebound exerciser according to this invention;

Figure 2 shows the underside of the exerciser of figure 1;

Figure 3 shows the exerciser of figure 1 with the skirting removed, and

Figures 4 to 7 show detailed views of the spring assembly of the exerciser.

Referring first to figures 1 to 3 the exerciser basically comprises a closed circular frame 1 mounted on legs 2. Although with this particular embodiment the frame is constructed of 25mm square bar section other cross-sectional sizes and shapes may also be used. A series of springs 3 are fitted around the inside of this frame to s.uspend a circular polypropylene mat 3A centrally within the device. The tension imposed on the mat is pre-set by imposing an initial deformation of about 307. on the springs so that a person's weight can be resiliently supported on any part of the webbing to allow jumping, jogging or other form of exercise.

The preferred manner of attaching the springs to the frame is best illustrated by figures 4 and 5 which show the connection from both the top and underside. The springs 3 engage in pairs around steel pins 4 which are welded to the inside surface 4A of the frame immediately below the upper edge 5. These pins are circular in cross-section and the central part 6 is bent into ^' a V shape to form a niche through which the hooked ends 7 of the springs are fitted. As the diameter of the pins is about 6 mm a relatively large rounded bearing surface is thereby provided for the

curved spring ends. This arrangement thus reduces the wear and noise observed in other prior art devices and also eliminates any protrusions above the upper surface of the frame. The opposite ends of the springs are attached to the periphery of the mat 3A by means of steel links 9 which extend through loops 10 sewn into the mat. To reduce wear and noise this link is also of rounded cross-section and of sufficient diameter to provide a large bearing surface area to engage the ends of the springs.

In accordance with another aspect of this invention it will be noted that the springs are also tapered whereby the diameters of the coils 11 progressively decrease towards each end. This has been found to substantially increase the life and durability of the springs by insuring that they deform uniformly over their entire length without exessive stress concentrations arising at the ends as occurs with previous apparatus.

Each spring is also preferably angled at about 45 degrees to the edge of the mat 3A rather than extending along diametrical lines as with earlier exercisers. This has the effect of producing a more uniform and resilient tension on the central area of the mat and is thought to result from the lines of force B as shown in figure 3 being confined to the peripheral section of the mat rather than passing directly across the center, it is to be understood however that the invention is not limited to any particular explanation or principle of operation.

In-order to provide a more finished appearance for the exerciser a padded skirt 12 is also fitted around the frame. As well as hiding the springs this forms a cushion over the rigid unsprung parts of the exerciser to protect the user.

It will thus be appreciated that this invention at least in the form of the embodiment disclosed provides a novel and

unique improvement in rebound exercisers. Clearly however the particular example described is only the currently preferred form of this invention and a wide variety of modifications may be made which would be apparent to a man skilled in the art. For example the shape and construction of the frame and leg members may be changed according to application or design preference. Similarly the number, size and arrangement of the springs can also be varied. Furthermore it should be noted that the invention is not limited to any particular material of construction.