JPH0112774Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a proposal for a magnetron having a structure that prevents a rise in temperature of the antenna wire that connects the vane of the magnetron and the exhaust pipe.

Generally, magnetrons are heated to a high temperature during the manufacturing process, and the exhaust pipe is connected to an exhaust device to exhaust the gas inside the magnetron. However, since the exhaust pipe comes into contact with the exhaust device, the temperature becomes lower than the magnetron itself due to heat conduction. However, when a magnetron is used, the above-mentioned antenna wire becomes high temperature due to the combination of heat conduction from the anode vane and heat generation due to Joule loss since it is itself a microwave transmission line, and the connected exhaust pipe becomes hot. The temperature is higher than that of the manufacturing process. Therefore, gas is released from the exhaust pipe, resulting in deterioration of characteristics.

The present invention relates to a structure for preventing the rise in temperature of the antenna wire, which is affected by the rise in temperature of the exhaust pipe, and will be described below with reference to the drawings.

Reference numeral 1 denotes an anode body having a resonant cavity inside, and anode vanes 2 protrude radially from the inner surface. 3 is a cylindrical conductor bonded to the end surface of the anode body 1, and 4 is a cylindrical insulator bonded to the other end surface of the cylindrical conductor, which is usually made of ceramics. Reference numeral 5 denotes an exhaust pipe adhered to the other end surface of the cylindrical insulator, which serves to connect an exhaust device (not shown) and a magnetron during the manufacturing process. Further, after completion of evacuation, the antenna wire is clamped and cut to form a vacuum sealing section, which has a length of approximately 1/4λ and also functions as a chiyoke body.
An antenna wire 6 connects the vane 2 and the exhaust pipe 5, and is made of a metal plate, such as a copper plate, and has a longitudinal slit 7 in the center. The width of this slit is smaller than the thickness of the body plate.

As with the above-mentioned structure, the antenna wire is made of a plate and has longitudinal slits, so the temperature of the antenna wire rises extremely and it is difficult to transfer the vane heat to the exhaust pipe, so gas is released due to the temperature rise around the exhaust pipe. This prevents deterioration of characteristics. The reason why the antenna wire of this invention prevents temperature rise is that first, by providing a slit in the plate, the cross-sectional area becomes small, which suppresses heat conduction as much as possible.
On the other hand, since the surface area of the antenna wire increases due to the slit, microwaves are transmitted through the metal surface, reducing the joule loss and preventing the antenna wire from generating heat.

[Brief explanation of the drawing]

The drawings show the magnetron of the present invention; FIG. 1 is a sectional view of a main part, FIG. 2 is a perspective view of an antenna wire of the magnetron of the present invention, and FIG. 3 is a perspective view of another embodiment. 1... Anode body, 3... Cylindrical conductor, 4... Cylindrical insulator, 5... Exhaust pipe, 2... Vane, 6... Antenna wire, 7... Slit.

Claims (1)

[Scope of utility model registration request] An anode body having a resonant cavity inside, an exhaust pipe fixed to the end face of the insulator through a cylindrical conductor and a cylindrical insulator from the end face of the anode body, and a vane protruding from the inner surface of the anode body. A magnetron in which an antenna wire connecting the exhaust pipes is made of a metal plate, and a longitudinal slit is provided in the plate.