Nippon Paint Compnay, Ltd.

Mazda Motor Corporation

Sankyo Dengyo Co. Ltd.

Kensuke Akutsu

Takanori Hara

Ikuo Tochizawa

Akinori Iwata

Koji Ueki

Makoto Moriyama

Kouichi Kuwano

Yuji Tanaka

Hirohiko Koge

Masatoshi Fujii

In a spark gap switch of a pulse generating circuit of a plasma generator T, an intermediate electrode , which is not connected to any electrical source, is disposed at a nearly middle position between a first spherical electrode and a second spherical electrode so as to hold respective spark gaps to the both spherical electrodes . Further, in the spark gap switch , switching operation is performed between the both spherical electrodes by causing two-stage spark discharge in the first spark gap between the first spherical electrode and the intermediate electrode , and in the second spark gap between the intermediate electrode and the second spherical electrode . Thus, in the spark gap switch , pulse voltage of high voltage and high frequency is stably generated for a long time, and further the spark gap switch may be made compact.

Spark gap switch and switching method thereof

A high voltage gap discharge switch is provided with a pair of sphere electrodes 1, projections 2 and a blower 5. The sphere electrodes 1 are separated by a discharge gap and oppose each other. The projections 2 are provided integrally at the mutually facing tips of the sphere electrodes 1, and have a projection length of 1/100 to 1/8 times the diameter of the sphere electrodes 1 and an outer diameter of 1/100 to 1/10 times. The blower 5 gives rise to an air current for expelling products produced on the projections 2 due to the generation of a spark discharge. The blower 5 supplies air to the discharge gap at a wind speed of 0.5 to 25 m/sec.-KW. One objective of the present invention is to stabilize the wave-form of a high voltage pulse and to increase its durability using a simple construction.

High voltage sphere-gap discharge switch, high voltage pulse generation

In a method of corona discharge processing of resin formings surface, excellent corona discharge processing is possible, even if there is a distance between the resin formings and the discharge electrode, by generating a high voltage pulse having a pulse width of 1 .mu.s or more, an average electric field strength of 4 to 20 kv/cm denoted by applied voltage (wave height) versus interelectrode distance, and a pulse frequency of 10 pps or more. This processing is performed by the apparatus which comprises arranging a transfer conveyor to transfer the resin formings, a counter-electrode placed in a down side of the transfer conveyor, a dielectric to cover a surface of the counter-electrode, and a number of discharge electrodes which are arranged in a definite distance above the resin formings along the transfer route.

Method and apparatus for corona discharge processing

A plasma generator including an excitation electrode and an opposite electrode confronting the excitation electrode such that plasma is generated upon impression of a high voltage between the excitation electrode and the opposite electrode. The plasma generator further includes granular material which is at least partially composed of dielectric grains and is provided between the excitation electrode and the opposite electrode.

Plasma generator

Growing community of inventors

Toyonaka, Japan

Kensuke Akutsu