Abstract: An implantable hearing aid device including a vibrational element which is mounted to the round window of the cochlea and a transmitter which can be mounted externally of the ear or within the mastoid bone of the skull. The transmitter includes a microphone for picking up sound waves and converting the sound waves into electromagnetic signals which are imparted to the vibrational element fixed to the round window of the cochlea. The placement of the vibrational element on the round window provides significant advantages over conventional implantable hearing aids which transmit vibrational impulses to the oval window of the cochlea through a pathway which interferes with normal hearing. With the implantable hearing device of the present invention, the normal pathway used for receiving acoustically input sound waves is left unobstructed.

Abstract: A system for supplying foam liquid concentrate via a concentrate pump to one or more water pump discharge outlets. The concentrate pump is powered by a variable output hydraulic drive which in turn is automatically modulated independently of the level of operation of the water pump by a control system which is responsive both to the water pressure developed by the water pump and to the foam liquid concentrate pressure developed by the concentrate pump.