Mitsubishi Denki Kabushiki Kaisha

Mitsuhiro Kishida

Takahiro Matsumoto

Takashi Inaguchi

Masashi Nagao

Hideto Yoshimura

Kazuki Moritsu

Shuji Ando

Katsumi Kondo

Shuichi Nakagawa

Shuuichi Nakagawa

An object of the present invention is to obtain a superconductive magnet, the size of which can be reduced by shortening the radial length of a magnetic device thereof and the refrigerating performance of which can be improved. A cylinder for fastening a refrigerator has an end facing an ambience of helium gas evaporating in a helium chamber and another end which is substantially horizontally fastened to a vacuum chamber. Further, the three-stage regenerative refrigerator is inserted and fastened to the cylinder for fastening the refrigerator. A heat insulator, such as a convection prevention tube, made of a hollow Teflon tube is wound around the outer surface of each stage of the cylinder of the three-stage regenerative refrigerator. The convection prevention tube is enclosed into a gap between the cylinder for fastening the refrigerator and the three-stage regenerative refrigerator without no undesirable gap so that heat convection of the helium gas is prevented.

Superconductive magnet

A cold accumulation type refrigerating machine having a high refrigeration efficiency. Rotation output of a stepping motor is converted to a reciprocative motion of a displacement member carrying a cold accumulator and disposed within a cylinder in which first and second closed chambers are defined above and below the displacement member, respectively. A compressed gas discharged from a compressor is introduced into the second closed chamber through the cold accumulator upon opening of a suction valve and undergoes expansion within the second closed chamber, the gas being then fed back to the compressor through the cold accumulator upon opening of an discharge valve, whereupon one cycle of refrigerating operation is completed. Rotation speed of the stepping motor is varied during every one cycle of operation by means of a pulse oscillation controller such that a time taken for the displacement member to reach a top dead center position from a time point at which the discharge valve is opened is increased while the remaining period of the one cycle is correspondingly shortened.

Cold accumulation type refrigerating machine

A reactor having a coil surrounded by a magnetic shield formed of laminated magnetic sheets. Connecting members pass through the central opening of the coil and are clamped between sheets of the magnetic shield. Each connecting member comprises a pair of connecting plates having opposite ends expanded. They are inserted from opposite sides of the central opening of the core, and are fixed together. The expanded parts at both ends of the connecting member increases the friction, and reduces vibration and noises.

Air-core reactor with a magnetic shield

A porcelain gas-filled bushing wherein a central conductor passes through a porcelain tube which is filled with an insulating gas, a fitting flange which is fastened to one end of the porcelain tube is grounded, and an electrode which encircles the central conductor at a predetermined spacing therefrom and which is covered with an insulating member is electrically connected with the fitting flange. Alternatively, several electrodes fitting within each other may be provided around the central conductor. In one embodiment the electrodes are conical and flare radially outwardly of said central conductor from a lower end toward an upper end thereof.

Porcelain gas-filled bushing with electrodes for moderating the electric

A bushing in which a conductor penetrates through the center of a porcelain tube of which the one end is closed, the other end of the porcelain tube is closed by a cone-shaped insulation spacer which protrudes into the porcelain tube and which also supports the conductor, a capacitor cone is disposed to surround the conductor and a predetermined portion of the insulation spacer in the porcelain tube, an insulating material is charged into the porcelain tube, the side opposite to the capacitor cone relative to the insulation spacer is coupled to a container which is filled with an insulating gas having a predetermined pressure and which accommodates electrical equipment, and the conductor is connected to the electrical equipment.

Bushing for gas-insulated electrical equipment

The invention comprises a bushing surrounding an electrical conductor, including a porcelain tube which employs a gaseous insulator, an insulating tube disposed with a space of small volume set relative to the inner periphery of the porcelain tube, the small space being filled with an insulating medium which is deformable with a predetermined force. According to the construction, when the porcelain tube has been damaged, its fragments can thus be prevented from scattering far. The flashover of the bushing can be prevented by disposing compression springs in the lower part of the insulating tube, and the electric field distribution of the outer surface of the bushing can be improved by coating the surface of the insulating tube with an electrically-conductive coating material.

A high voltage seismic bushing charged with an insulating material has a procelain tube having an adapter rigidly connected to one end of the tube. The adapter is flexibly connected to a mounting flange such that the porcelain tube is free to move relative to the mounting flange in the event of an earthquake. The means for flexibly connecting the adapter to the mounting flange utilizes a spring mechanism to absorb the energy through friction to attenuate the movement of the porcelain tube. A resilient buffer member is interposed between the adapter and the mounting flange to provide a predetermined spacing therebetween and absorb the impact due to the movement of the adapter relative to the mounting flange. A sealing member seals the interface between the adapter and the mounting flange for containing the insulating material charged therein.

High voltage seismic bushing

A high voltage seismic bushing charged with an insulating material has a porcelain tube having an adapter rigidly connected to one end of the tube. A connecting plate is rigidly connected to a mounting flange. The adapter is flexibly connected to the connecting plate such that the porcelain tube is free to move relative to the mounting flange in the event of an earthquake. The means for flexibly connecting the adapter to the connecting plate utilizes a damping mechanism to attenuate the movement of the porcelain tube. A resilient buffer member is interposed between the adapter and the connecting plate to provide a predetermined spacing therebetween and absorb the impact due to the movement of the adapter relative to the connecting plate. A sealing member seals the interface between the adapter and the connecting plate for containing the insulating material charged therein.

Growing community of inventors

Amagasaki, Japan

Mitsuhiro Kishida