Abstract: A solar water heater including an angularly inclined housing structure. The housing structure includes an inlet for receiving water and an outlet for discharging heated water. Encased within the housing, lies a plurality of heating pipes for absorbing solar energy. The plurality of heating pipes is operatively connected to the fluid inlet. The plurality of heating pipes encompasses a plurality of water storing pipes disposed therein. The plurality of water storing pipes is in fluid communication with the plurality of heating pipes and the fluid outlet. In this manner, the plurality of heating pipes act as a solar receiver, and the enclosed plurality of water storing pipes act as a storage tank. A solar water heating and storage device wherein a solar receiver and water storage tank are integrated into a single unit.

Abstract: An electric drive attachment for a wheelchair. The drive includes an electric motor constituting the input member of the drive, a wheel adapted to touch the ground and to drive the wheelchair by frictional contact with the ground, and the wheel constituting the output member of the drive. The input member and the output member constitute an integral unit carried by a sleeve-like member slidably mounted to a first position of a mounting member attachable to the wheelchair, and first means are provided to allow the unit to be shifted to, and arrested at, at least two different positions along the first position of the mounting member. In the first position the unit is closer to a reference point on the wheelchair and in the second position the unit is more remote from the reference point.

Abstract: The invention provides an electric exercising appliance comprising a frame comprising at least one member and at least indirectly mountable on a supporting surface, an electric motor adapted to operate in a first mode in which it functions as generator, drawing muscular energy from the user of the appliance and converting the muscular energy into electrical energy convertible into other forms of energy, and in a second mode in which the motor functions as mover, drawing electrical energy from a source thereof and moving, and thereby exercising, limbs of the user, first switch for switching over from the first to the second mode and vice-versa, first adjustment switch for adjusting the energy to be expended by the user in the first mode, and second adjustment switch for adjusting the speed of the motor in the second mode.

Abstract: An electric drive attachment for a wheelchair. The drive includes an electric motor constituting the input member of the drive, a wheel adapted to touch the ground and to drive the wheelchair by frictional contact with the ground, the wheel constituting the output member of said drive and speed-reducing means interposed between the input member and the output member. The input member, the speed-reducing means and the output member are mounted on a common mounting member attachable to the wheelchair, and means are provided to cause the common mounting member to selectively assume a first position in which the output member is in contact with the ground, and at least one second, non-contact position, in which the output member is lifted off the ground.