Abstract: A steerable ultra-low patient bed incorporates means for maintaining verticality of the caster stem at all height positions of the bed, and means for selectively locking the caster assemblies of the bed in a desired locking position. The means for selectively locking the caster assemblies may be actuated from either end of the bed using a central actuation mechanism. The bed preferably has legs that are pivotally and translatably attached at their upper end to the bed frame, and caster support members that are longitudinally aligned with the bed pivotally attached to the lower end of each leg. Each caster support member has a single caster assembly attached thereto. The means for maintaining verticality of the caster stem incorporates a constraint means that urges the caster support member in a direction of rotation opposite that of the leg during adjustment of the height of the bed.

Abstract: A steerable ultra-low patient bed that incorporates a means for maintaining verticality of the caster stem at all height positions of the bed and a means for selectively locking the caster assemblies of the bed in a desired locking position. The means for selectively locking the caster assemblies may be actuated from either end of the bed using a central actuation mechanism. The bed according to the present invention has legs that are pivotally and translatably attached at their upper end to a frame of the bed and caster support members that are longitudinally aligned with the bed pivotally attached to the lower end of each leg. The caster support members each have a single caster assembly attached thereto. The means for maintaining verticality of the caster stem incorporates a constraint means that urges the caster support member in a direction of rotation opposite to that of the leg during adjustment of the height of the bed.

Abstract: A microwave or radio frequency device including an applicator for receiving an object to be processed, and a plurality of generators supplying power to the applicator via propagation guides. According to the invention, three propagation guides propagating the microwaves or radio frequencies generated by three respective generators are mounted on three respective plates defining a three-dimensional rectangular axis system, and symmetrical relative to a ternary axis of symmetry of the axis system, whereby the generators supplying power to the applicator are mutually decoupled. The three propagation guides have a rectangular cross-section and are mounted on respective plates in such a way that the short sides of the rectangular cross-section of said guides are orthogonal in pairs, or are coaxial cables extending in a longitudinal propagation direction perpendicular to the plates with one exposed end thereof extending into the applicator.

Abstract: A microwave or radio frequency device including an applicator for receiving an object to be processed, and a plurality of generators supplying power to the applicator via propagation guides. According to the invention, three propagation guides propagating the microwaves or radio frequencies generated by three respective generators are mounted on three respective plates defining a three-dimensional rectangular axis system, and symmetrical relative to a ternary axis of symmetry of the axis system, whereby the generators supplying power to the applicator are mutually decoupled. The three propagation guides have a rectangular cross-section and are mounted on respective plates in such a way that the short sides of the rectangular cross-section of said guides are orthogonal in pairs, or are coaxial cables extending in a longitudinal propagation direction perpendicular to the plates with one exposed end thereof extending into the applicator.

Abstract: There is described a bed comprising a frame, a rail pivotally mounted on the frame and pivotable between a guardrail position and an open position, a distance between the frame and the rail when the rail is in the guardrail position, and a resilient element mounted on the frame or on the rail or on both the frame and the rail to fill the distance between the frame and the rail when the rail is in the guardrail position to thereby reduce rattling of the rail when the rail is in the guardrail position. The resilient element is preferably a resilient roller mounted on the frame, the roller engaging the rail when the rail is pivoted into the guardrail position.

Abstract: Output amplifier stage (1) of a high frequency generator (1) with tube (2) operating in class B or C has its output (5) looped back on the input (4) by means of a coaxial line (31) with a length equal to approximately the wave length corresponding to the operating frequency. The apparent gain of the amplifier stage (1) is thus increased and the output power from an intermediate amplifier (24) can be correspondingly reduced, amplifying a stable signal at the operating frequency.

Abstract: There is described a bed comprising a frame, a rail pivotally mounted on the frame and pivotable between a guardrail position and an open position, a distance between the frame and the rail when the rail is in the guardrail position, and a resilient element mounted on the frame or on the rail or on both the frame and the rail to fill the distance between the frame and the rail when the rail is in the guardrail position to thereby reduce rattling of the rail when the rail is in the guardrail position. The resilient element is preferably a resilient roller mounted on the frame, the roller engaging the rail when the rail is pivoted into the guardrail position.

Abstract: Output amplifier stage (1) of a high frequency generator (1) with tube (2) operating in class B or C has its output (5) looped back on the input (4) by means of a coaxial line (31) with a length equal to approximately the wave length corresponding to the operating frequency.

Abstract: A gas phase catalytic reactor comprising a metal vessel defining a confinement volume in which electromagnetic waves are generated at a frequency greater than 10 MHz. The confinement volume contains a porous catalyst which is heated by the electromagnetic waves and which has a flow of reactive gas passing therethrough. In order to guarantee that the gas reacts only when in contact with the catalyst, a heat exchanger is used to cool the gas suddenly as it leaves the confinement volume.

Abstract: Catalytic process for controlled oxidation of methane using microwaves, characterized in that it makes use of a catalyst exhibiting in its structure electrical charge defects and geometric deformations enabling it to absorb electromagnetic energy, or microwaves, under the effect of an electromagnetic field.

Abstract: Apparatus for heating a silica optical fiber in a fiber-drawing installation. The apparatus is disposed at the outlet of a fiber-drawing oven to raise the optical fiber to a temperature greater than 1000.degree. C. The apparatus is constituted by a microwave generator coupled to a resonant cavity formed by a helically-wound metal wire helix fixed at opposite ends to two short circuit metal plates respectively, with the optical fiber running substantially along the axis of the helix and the helix concentric about the running fiber.

Abstract: Apparatus for measuring continuously and without contact the thickness of a thin conducting layer on a running insulating support of the fiber or tape kind, wherein the apparatus includes:a microwave generator associated by coupling means to a resonant cavity comprising a metal wire in the form of a helix which is fixed at its ends to two metal plates, said insulating support being suitable for running substantially along the axis of said helix; andmeans for coupling said cavity to a detection device for detecting the transmission factor of said cavity, which factor is directly a function of said thickness, said measurement being performed at constant frequency.

Abstract: A resonant high-frequency or micro-wave applicator for the thermal treatment of a flat material is disclosed. This applicator comprises a flat capacitor between the plates of which the material moves and an inductor which is constituted by a metal band extending transversely the plate acting as hot electrode. The inner face of the plate acting as ground electrode is divided into elementary sections by an assembly of longitudinal grooves. Preferably, the same applies to the inner faces of the plate acting as hot electrode and the inductor.

Abstract: The invention provides a microwave feeder or applicator, that is to say a resonant chamber for coupling to a source of microwaves, arranged for the microwave treatment of a sample of material, comprising two main conductive walls extending parallel to a common axial direction and each having two projections and a central part joining the two projections, the projections of the two walls facing one another in pairs whereas the central parts of the two walls likewise face one another and define a region in which there is a local increase in the distance between the two main walls; a first conductive end wall forming a short-circuit and extending in a plane forming a cross-section of the main walls; a second conductive end wall forming a second short-circuit extending in a plane forming a cross-section of the main walls, and a coupling means for supplying microwave energy to the feeder, the dimensions of the cavity formed by the main end walls being arranged so that the cavity resonates almost exclusively in the

Abstract: An applicator comprising a generator of microwaves, said microwaves having a mode of propagation and a wavelength, an enclosure for receiving material to be treated, a coupler coupling the generator and the enclosure so that the generator delivers microwave energy distributed in resonance for said mode of propagation in a given direction, a first short-circuit device situated at one end of said enclosure with respect to said direction, a device for displacing the first short-circuit device by a reciprocating movement in said direction, and means for maintaining the resonance in spite of the displacements of the first short-circuit device.

Abstract: In a process for applying microwaves to a material, consisting in applying two beams from a single source to an inlet face of the material putting in phase, the beams reflected by the inlet face of the material superposing the two reflected beams to form a superposed beam, which is returned into the material, the improvement which consists in that the material is divided into two portions which are electromagnetically decoupled.