Abstract: A diathermy apparatus has a power circuit operative at a selected, fixed frequency. An applicator head, for providing therapeutic treatment, has an irradiating portion. A transmission line connects the power circuit and applicator head, and is of a length so that, at the frequency, a selected minimum power is delivered to the applicator head when unloaded, the length further being such that a selected maximum amount of power is delivered to the applicator head when it is in a loaded position in close proximity to a patient load. The diathermy apparatus also includes a cabinet and portable base, wherein the portable base mounts the applicator head, and provides a carriage for the cabinet. The applicator head has an internal fan for cooling components of the applicator head. A display is provided for displaying the actual power consumed by the patient load. A processor independently controls the pulse modulator and power circuit in digital increments on a selected scale.

Abstract: A diathermy apparatus has a power circuit operative at a selected, fixed frequency. An applicator head, for providing therapeutic treatment, has an irradiating portion. A transmission line connects the power circuit and applicator head, and is of a length so that, at the frequency, a selected minimum power is delivered to the applicator head when unloaded, the length further being such that a selected maximum amount of power is delivered to the applicator head when it is in a loaded position in close proximity to a patient load. The diathermy apparatus also includes a cabinet and portable base, wherein the portable base mounts the applicator head, and provides a carriage for the cabinet. The applicator head has an internal fan for cooling components of the applicator head. A display is provided for displaying the actual power consumed by the patient load. A processor independently controls the pulse modulator and power circuit in digital increments on a selected scale.

Abstract: A method and apparatus for simultaneously operating two diathermy treatment heads in close proximity without interference caused by phase and frequency differences. Each diathermy head has a drive circuit powered by a master oscillator providing RF energy. Each head can be used alone with RF drive from its own oscillator. When the heads are to be used in close proximity, they are coupled by coaxial cable, and one oscillator is automatically disabled to permit the other oscillator to furnish the RF drive for both systems. The RF drive is then coherent in phase and frequency in both systems, so the two diathermy heads do not "fight" each other.

Abstract: This invention deals with an improved electrostatic shield which is adapted to be mounted on the applicator of a conventional diathermy apparatus between the radiating electrode thereof and the patient receiving treatment. The shield is comprised of a first and a second plurality of electrically conductive strips which form the body portion of the shield and which encircle the current carrying coil of the radiating electrode. The strips likewise form the face portion of the shield and define a plane which is generally parallel to the plane formed by the current carrying coil.Each strip of the face portion is preferably coupled with one of the strips of the body portion. However, the face portion strips of the shield extend generally radially inward from the outer periphery of the surface defined by the face of the shield. These strips then terminate within the inner portion of the area defined by the shield such that the terminating end of the strips are electrically insulated from each other.

Abstract: This invention discloses a method and apparatus for accurately measuring and controlling the amount of power being absorbed by a load within the irradiating region of a diathermy applicator head. A desired power setting is initially preset into the diathermy apparatus. Thereafter, the diathermy apparatus is keyed on for a predetermined duty cycle causing RF energy to be generated within the applicator head during this time period. The level of power being absorbed by the load is then ascertained by measuring voltage and current flow in the head during the duty cycle. In the preferred embodiment of the invention, the electrostatic energy generated in the applicator head is attenuated by an electrostatic shield. Attenuation of the electrostatic energy improves the stability of the diathermy apparatus by significantly reducing electrostatic coupling between the applicator head and its attendant load.