Background art As a rule, bathtubs are made as longitudinal containers with a flat or deflected non-articulated bottom and with sidewalls featuring a more or less complex shape.

The flat bottom of the bathtub permits to use it also for taking the shower since the risk of slipping on the damp and relatively smooth surface of the flat bottom is sensibly inferior to that in a bathtub with deflected bottom.

However, the flat or even deflected non-articulated bottom of the bathtub involves considerably high water consumption if the person having a bath wishes to be immersed under the water level with the whole of their body. Also, the person having a bath, especially a person whose ability to move has been reduced by age, illness or accident, finds it difficult repeatedly to sit down and to stand up in the bathtub with a flat or even deflected not-articulated bottom. Besides, the frequent disproportion between the height of the person having a bath and the length of the bathtub with flat or even deflected bottom renders it difficult for the person to take up the most convenient relaxation position.

The problems of the persons having a bath connected with the movements of. standing up and sitting down in a bathtub are dealt with in the published patent application DE OS 41 23 635 describing a bathtub with articulated bottom of the bath container and articulated lean-back surface for the back of the person having a bath, said lean-back surface being continued as a head rest for the person having a bath.

The bottom of the bath container comprises a sitting surface slightly raised above the basic surface of the bottom of the bath container. The basic surface of the bottom of the bath container is the lowest surface of the bath container and passes at the side opposite to said lean-back surface into a foot support surface oriented obliquely upwards. The foot support surface then passes into a horizontal lean surface for heels of the person sitting in the bathtub with stretched out legs. In continuation, the horizontal lean surface for heels passes into the cover of the bath container. Situated on the upper edge of the bath container is a grip helping the person having a bath to sit down and to stand up.

The drawback of this solution consists in a small difference in height between the basic surface of the bottom of the bath container and the sitting surface so that the person having a bath must develop considerabie effort to sit down and in particular to stand up which is difficult for persons with reduced movement ability.

Another drawback consists in that even after assuming the partly lying relaxation position not all body muscles are relieved because the legs of such a partly lying person lean only in the upper portion of the thighs and on the heels and feet which is not sufficient for relieving all body muscles.

Still another drawback consists in the big volume of the bath container necessarily involving increased water consumption when having a bath with the whole body immersed under the water level.

The published patent application PCT/US91/06910 describes a bathtub with articulated walls and complements. The bathtub according to this invention comprises two articulated sidewalls situated opposite each other and passing into two mutually opposite situated articulated lean-back surfaces, each of them comprising a head rest, with the lower part of the cover of the bath container passing into the bottom of the bath container. One of the sidewalls carries a grip to help the person having a bath to move.

The bath container also contains a set of massage nozzles seated in the walls of the cover of the bath container.

The drawback of this bathtub consists in the risks involved for persons with reduced movement ability in taking a shower as well as in large dimensions of the bath container which, on the one hand, require a considerably high water consumption for a bath with the whole body immersed under the water level and, on the other hand, radically reduce the effectiveness of the action exerted by the massage nozzles on the person having a bath.

The invention aims at doing away with, or at least at minimizing, the drawbacks of the state of art.

Principle of the invention The goal of the invention has been reached by a multi-purpose bath container according to the invention whose principle consists in that the bottom of the bath container contains in the direction from the lean-back surface of the bath container to the heel wall of the bath container a sitting section passing into an upwards sloping middle part which in its turn passes into a heel part This invention reduces the water quantity required for immersing the whole body of the person having a bath under the water level, and also permits to take up a more convenient relaxation position relieving all muscles of the whole body.

To take up a still more convenient relaxation position, the heel part of the bottom is oriented obliquely upwards, and its angle of inclination with the horizontal plane is inferior to the angle of inclination of the middle part of the bottom with the same plane.

Preferably, the mutual distance between the two sidewalls decreases in the direction from the lean-back wall to the heel wall, thus further reducing the quantity of water required for immersing the whole body of the person having a bath under the water level.

Preferably, the longitudinal symmetry plane of the bath container makes with the longitudinal symmetry plane of the edge plate an acute angle different from zero which permits to increase the length of the bath container without increasing the length of the edge plate and thus to use the bathtub even in relatively small rooms.

According to another preferred embodiment of the invention, the longitudinal symmetry plane of the bath container makes with the longitudinal symmetry plane of the edge plate such an acute angle different from zero that one of the sidewalls of the bath container is parallel with its adjoining lateral edge of the edge plate thereby increasing the surface of the edge plate on the opposite side of the bath container which promotes the creation of a rest surface or of a sitting surface.

According to still another preferred embodiment of the invention, the bottom of the bath container contains a tread surface for having the shower situated in the plan view between the transition of the lean-back wall to the sitting section of the bottom of the bath container and the heel wall, with at least a part of the tread surface for taking a shower passing into a circumference wall, the latter in its turn passing into the respective walls of the bath container and/or into the edge plate. In the design of the bathtub, the shape and position of the tread surface preferably may be modified as needed.

In transverse direction, the tread surface for taking a shower is in the plan view preferably situated between the longitudinal symmetry plane of the bath container and one of the side edges of the edge plate, said side edge of the side plate being in plan view concurrent with its adjoining sidewall of the bath container which provides for a width of the respective surfaces of the bottom of the bath container sufficient to permit the person having a bath to take up a convenient relaxation position.

According to another preferred embodiment of the invention, at least a part of the tread surface protrudes outside the edge plate in the direction outside this edge plate thus additionally increasing the width of the respective bottom surfaces and by means of this also the convenience of the person having a bath in its relaxation position.

According to still another preferred embodiment of the invention, the tread surface for taking a shower is the lowest surface of the bath container thus permitting to obtain between the tread surface, the other walls of the bath container, and the edge plate level differences suitable for good water flow-off.

By its design, the tread surface for taking a shower permits to use the multi- purpose bathtub also for taking a shower. Unlike the current types of bathtubs, it reduces to a minimum the risk of slipping and injury when taking a shower.

Suitable level differences between the respective surfaces of the bath container may be advantageously used by the persons having a bath to sit down to, and to stand up from, the relaxation position. Persons with reduced movement ability can sit down without risk, for instance on the heel part of the bottom of the bath container with the feet put on the tread surface for taking a shower, and can then easily and securely move to the relaxation position with the whole body immersed under the water level, or they can have a shower in a sitting position, and can then more easily and securely stand up and securely get out of the bathtub.

To increase the security of the person while moving in the bathtub, a part of the tread surface for taking a shower passing into a sidewall of the bath container and/or into the respective edge plate is preferably fitted with a grip.

According to another preferred embodiment, the bath container is fitted with a set of massage nozzles situated, preferably in recesses, in the bottom or in the respective walls of the bath container so as to obtain turbulent streams in said recesses and thus to increase the relaxation effectiveness of the massage nozzles, further supported by the ergonometrically shaped bath container, on the person having a bath in this multi-purpose bathtub.

Brief Description of the Drawings An example of embodiment of a multi-purpose bathtub is shown in the enclosed drawings in which Fig. 1 shows one of the particular embodiments of the multi-purpose bathtub in what may be termed a diagonal arrangement, Fig. 2 another particular embodiment of the multi-purpose bathtub in a normal arrangement, Fig. 3 a cross- section of the multi-purpose bathtub shown in Fig. 2 in the longitudinal symmetry plane of the bath container, Fig. 4 another particular embodiment of the multi-purpose bathtub in a normal arrangement, Fig. 5 the position of the tread surface in the plan view of a particular embodiment of a multi-purpose bath container in the diagonal and normal arrangements, Fig. 6 a particular embodiment of the multi-purpose bathtub in a normal arrangement and with tread surface, Figs. 6a, 6b longitudinal sections of the multi-purpose bathtub shown in Fig. 6, Figs. 7, 7a the embodiment of the multi-purpose bathtub shown in Figs. 6, 6b with a grip, Figs. 8, 8a the embodiment of the multi- purpose bathtub shown in Figs. 6, 6b with a grip of a shape different from that shown in Figs. 7, 7a, Figs. 9a to 9d the process of entering, sitting down, and standing up of the person having a bath in the multi-purpose bath container, and Figs. IOa to lOg the variants of sitting and taking a shower in the multi-purpose bath container.

Specific Description In the example of embodiment shown in Figs. 1, 2, and 3, the bathtub comprises a bath container A followed by an edge plate B containing two side edges B1 and B2.

The longitudinal symmetry plane of the bath container A makes with the longitudinal symmetry plane of the edge plate B an acute angle oc which is either different from zero (see Fig. 1) or equal to zero (see Fig. 2).

The bath container A has a bottom 4 and a cover Al comprising two sidewalls 1 passing at one end into an articulated lean-back wall 2 and both of them passing at the opposite end of the bath container A into an articulated heel wall 3. A part of the bottom 4 serves as a tread surface when using the shower.

In the example of embodiment shown in Figs. 1 and 2, the mutual distance between the two sidewalls 1 decreases in the horizontal direction from the lean-back wall 2 to the heel wall 3 in the embodiment shown in Fig. 1, the chosen value of the angle a ensures the parallelism of one of the sidewalls 1 with the respective side edge B2 of the edge plate B.

In another example of embodiment, shown in Fig. 4, the mutual distance between the two sidewalls 1 in the horizontal direction is constant. In vertical direction, the mutual distance between the two sidewalls 1 decreases from the upper edge of the bath container A towards the bottom 4 of the bath container A.

In the examples of embodiment shown in Figs. 1, 2, 3, and 4, the lean-back wall 2 is made as a part of the cover of a well-known frustrum of a cone. In another, not shown example of embodiment, the lean-back wall 2 is made as a general oblique deflected surface. The lean-back wall 2 passes in its lower part into the bottom 4 and in its upper part, into the edge plate B.

In the examples of embodiment shown in Figs. 1, 2, 3, and 4, the heel wall 3 is made as a part of the cover of a well-known frustrum of a cone. In another, notshown example of embodiment, the heel wall 3 is made as a general oblique deflected surface. The heel wall 3 passes in its lower part into the bottom 4 and in its upper part, into the edge plate B.

In the longitudinal plane of symmetry, the heel wall 3 makes an acute angle 33 with the vertical plane perpendicular to the longitudinal symmetry plane of the bath container A; and the lean back wall 2 makes an acute angle 2 with the vertical plane perpendicular to the longitudinal symmetry plane of the bath container A the magnitude of the angle 2 being superior to that of the angle , as shown in Fig. 3.

The bottom 4 of the bath container A contains a sitting part 41, a middle part 42, and a heel part 43 that pass into the leanback wall 2 into the respective parts of the two sidewalls 1 of the heel wall 3, and mutally into the respective adjoining parts of the bottom 4. All the transition sections are rounded, and the sitting part 41 and/or the heel part 43 serves as a tread surface for the person when taking a shower.

With respect to the upper edge of the bath container A the sitting part 41 of the bottom 4 is the lowest surface of the bath container A. The sitting part 41 of the bottom 4 is fitted with a not shown well-known outlet hole of the bath container A.

The middle part 42 of the bottom 4 is made as a oblique surface connecting the sitting part 41 of the bottom 4 with the heel part 43 of the bottom 4 which is raised with respect to the sitting part 41 of the bottom 4 as shown in Fig. 3.

In the shown example of embodiment, the heel part 43 of the bottom 4 slightly slopes down in the direction of the longitudinal plane of symmetry of the bath container A from the heel wall 3 towards the middle part 42 of the articulated body 4, but its angle of inclination with respect to the horizontal plane also can be equal to zero.

The edge plate B surrounds the bath container A and the two sidewalls 1, the lean-back wall 2 and the heel wall 3 pass into the edge plate B as shown in Figs. 1, 2, 3, 4.

In another example of embodiment of a multi-purpose bathtub, shown in Figs. 5, 5a, the bottom 4 of the bathtub A comprises a tread surface 5 for the person taking a shower. The tread surface 5 is situated lower than the sitting part 41 of the bottom 41 adjoining it, and is situated in the plan view in transverse direction at the side edge B1 of the edge plate B, and in longitudinal direction, between the sitting part 41 of the bottom 4 and the heel wall 3 as shown in Figs. 5, 5a.

In another, not shown example of embodiment, the tread surface 5 for the person taking a shower is situated in the direction from the lean-back wall 2 to the heel wall 3 between the transition of the lean-back wall 2 into the sitting part 41 of the bottom 4 and the heel wall 3 of the bath container A.

In the bathtub design, the plan view position of the tread surface 5 may change in the longitudinal and/or transverse direction as needed, as shown in Figs 5, 5a by the arrows X and Y, and can reach into, or even outwards out of, the edge plate B.

In the example of embodiment shown in Fig. 5, the longitudinal symmetry plane of the tread surface 5 for taking a shower is parallel with the longitudinal symmetry plane of the bath container A. In the example of embodiment shown in Fig. 5a, the longitudinal symmetry plane of the tread surface 5 for taking a shower is parallel with the longitudinal symmetry plane of the edge plate B. In another, not shown example of embodiment the longitudinal symmetry plane of the tread surface 5 for taking a shower makes an acute angle, different from zero, both with the longitudinal symmetry plane of the bath container A and with the longitudinal symmetry plane of the edge plate B.

The tread surface 5 for taking a shower contains a well-known outlet hole of the bath container A. At its circumference, the tread surface 5 for taking a shower passes into an oblique circumference wall 51 whose parts pass then into the respective parts of the other walls of the bath container A or directly into the edge plate B, transition sections are rounded.

In the examples of embodiment shown in Figs. 5, 5a, the plan view of the tread surface 5 for taking a shower is a rectangle. In another, not shown example of embodiment, the plan view of the tread surface 5 for taking a shower is a square. In another not shown example of embodiment, the plan view of the tread surface 5 for taking a shower can be of any general shape.

In the example of embodiment shown in Figs.6, 6a, 6b, the longitudinal symmetry plane of the bath container A makes with the longitudinal symmetry plane of the edge plate B such an acute angle cc that one of the sidewalls 1 of the bath container A is parallel with the side edge B2 of the edge plate B the so-called diagonal arrangement. Here, the tread surface 5 for taking a shower is situated in the transverse direction between said longitudinal symmetry plane of the bath container and the outer edge B1 of the edge plate B and is oval-shaped.

In another example of embodiment, the circumference of the plan view of the tread surface reaches in the direction out of the bath container A as far as behind the side edge B1 of the edge plate B, as shown in Figs. 5, 5a with broken line Y1.

In the example of embodiment shown in Figs. 6, 6a, 7; 7a, 8, 8a, a first part of the circumference wall 51 of the tread surface 5 for taking a shower is made as a part of one sidewall 1 a second part of the circumference wall 51 of the tread surface 5 for taking a shower joins the sitting part 41 of the bottom 4, and a third part of the circumference wall 51 of the tread surface 5 for taking a shower passes into the middle part 42 of the bottom and into the heel part 43 of the bottom 4 thus creating various differences of level between the tread surface 5 for taking a shower and the sitting part 41 of the bottom 4 between the tread surface 5 for taking a shower and the heel part 43 of the bottom 4 and between the tread surface 5 for taking a shower and the edge plate B.

Situated in the horizontal plane in the transition sections of each of the two sidewalls 1 into the lean-back wall are the well-known hand supports 11, and the upper edge of the leanback wall 2 passes into a well-known head rest 12 that in its turn passes into the edge plate B. Situated on a part of the circumference wall 51 of the tread surface 5 for taking a shower constituting a part of one of the sidewalls 1 is a grip shaped at will, as is shown in Figs. 7, 7a, 8, 8a.

In another, not shown example of embodiment, the bath container A further comprises a set of massage nozzles 14 situated in the recesses of the respective walls and/or on the bottom of the bath container Q. Their position and number on each wall of the bath container A is variable.

Figs 9a to 10g show the most usual ways of using the multipurpose bathtub. The person intending to have a bath puts one leg over the front edge of the bathtub and treads on the tread surface 5. Having crossed the bathtub edge also with the other leg, the person can sit down on the enlarged front edge of the bathtub, see Fig. 9a, then can put the other leg as well on the tread surface 5 and after this can sit down on the heel part 43 of the bottom 4 see Figs. 9b, 10d and in this position, for instance, take a shower, see Fig. 10d. The person standing on the tread surface can take a shower in various positions as shown in Figs. 10e, 10f, IOg.

To reach the bathing and relaxation position, the person sitting on the heel part 43 of the bottom 4 moves, still sitting, on the heel part 43 and on the middle part 42 onto the sitting part 41 of the bottom, see Figs. 9c, 9d. By raising then the legs on the heel part 43 of the bottom 4 see Fig. 9e, the person assumes the bathing and relaxation position in which their body is to a maximum extent supported and immersed in the water and which permits to lie in a relatively short bathtub even to relatively tall persons. The complete bathing and relaxation position is shown in Figs 10a, 10b, and its variant with the raised back, in Fig. 10c.

To leave the bathtub, the person can proceed in reverse order as compared with the getting in and sitting down which is advantageous in particular for persons with reduced movement ability. Persons not handicapped in this way can sit down in the bathtub in usual way.