JPH0570895B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Field of Industrial Application) This invention relates to a method for manufacturing a magnetron.

(Prior Art) Generally, a magnetron is constructed as shown in FIG. 4, and has a plurality of vanes 2 fixed to the inside of an anode cylinder 1. Pole pieces 3 and 4 are fixed to both open ends of the anode cylinder 1, respectively, and an input part 5 and an output part 6 are protruded from each pole piece 3 and 4, and the output part 6 has an exhaust pipe. 7 are connected. Furthermore, a cathode filament 8 is disposed along the axis of the anode cylinder 1, and this cathode filament 8
are connected to cathode support rods 9 and 10 passing through the input section 5.

On the other hand, an antenna lead 11 is led out from one of the plurality of vanes 2, and this antenna lead 1
1 is inserted into the exhaust pipe 7 through the output part 6.

Such a magnetron is connected as shown in FIG. 5 at the time of exhaustion, the cathode support rod 9 is connected to the transformer 13 via the filament lead 12, and the cathode support rod 10 is connected to the transformer 13 via the filament lead 14 in direct current. It is connected to a power source 15. Further, an anode connecting ring 16 is attached to one end of the anode cylinder 1, and this anode connecting ring 16 is grounded by an anode lead 17. Further, the exhaust pipe 7 is tightened and sealed with a lock nut 19 to a manifold 18 of a vacuum evacuation device.

For evacuation, the anode cylinder 1 is kept at ground potential via the anode connection ring 16 and the anode lead 17, the cathode support rods 9 and 10 are set at a negative potential, and a high voltage is applied. Electrons emitted from the heated cathode filament 8 are pulled by the anode cylinder 1, causing a current to flow through the anode cylinder 1. The temperature of the anode cylinder 1 rises due to the Joule heat generated by this electron bombardment, and gas can be discharged from the anode structure of the magnetron.

(Problems to be Solved by the Invention) The conventional techniques described above have the following disadvantages.

Since the anode connecting ring 16 is made of metal, it oxidizes as the temperature of the anode cylinder 1 rises during exhaust, resulting in poor contact with the anode cylinder 1 and making it impossible to perform stable exhaust.

Three lead wires are required during evacuation, and there is a risk that the filament leads 12, 14 and anode lead 17 may come into contact with each other, and if they come into contact, the magnetron cannot be evacuated.

The present invention solves the above-mentioned disadvantages and provides a method for manufacturing a magnetron that can perform electron bombardment and exhaust while keeping the anode cylinder at ground potential without requiring an anode connection ring or anode lead. The purpose is to

[Structure of the Invention] (Means for Solving the Problems) This invention has a plurality of vanes fixed in an anode cylinder, an antenna lead led out from one of the vanes and inserted into an exhaust pipe, and an antenna lead inserted into the exhaust pipe. In a method for manufacturing a magnetron, in which exhaust is performed by connecting a tube to a vacuum evacuation device and keeping the anode cylinder at ground potential, the exhaust tube is slightly caulked and crushed, and the exhaust is brought into electrical short-circuit contact with the antenna lead. This method of manufacturing a magnetron involves evacuating the anode cylinder while maintaining it at ground potential through a tube and an antenna lead, and tipping off the exhaust pipe at the final stage of the exhaust process.

(Function) According to the present invention, the anode cylinder can be reliably and easily maintained at ground potential and evacuated while performing electron bombardment, and an anode connection ring or anode lead is not required.

(Example) Hereinafter, an example of the present invention will be described in detail with reference to the drawings.

The manufacturing method of the present invention is configured as shown in FIGS. 1 to 3, and the same parts as in the conventional example (FIG. 4) are given the same reference numerals. (Figure 5) Exhaust pipe 7
is connected to the manifold 18 of the vacuum evacuation device. Then, as shown in FIGS. 1 and 2, the exhaust pipe 7 is slightly caulked and crushed by the caulking device 20 to bring the exhaust pipe 7 and the antenna lead 11 into electrical short-circuit contact. Note that the exhaust pipe 7 is grounded through an exhaust stand. Additionally, this caulked portion maintains ventilation due to the exhaust pipe. In this way, electron bombardment is performed while the anode cylinder 1 is kept at the ground potential via the exhaust pipe 7 and the antenna lead 11, and is evacuated. Then, the exhaust pipe 7 is tipped off at the final stage of the exhaust process. A in FIG. 2 indicates the position where it is crimped and crushed.

In the above case, when the exhaust pipe 7 is slightly caulked and crushed by the caulking device 20, it may be circumferentially crushed 21 or linearly crushed 22, as shown in FIGS. 3a and 3b.

[Effects of the Invention] According to the present invention, in degassing the magnetron anode structure by electron bombardment during exhaust,
There is no need for an extra anode connection ring or anode lead for grounding the anode cylinder, and stable anode grounding is possible.

[Brief explanation of drawings]

FIGS. 1 and 2 are cross-sectional views showing a method of manufacturing a magnetron according to an embodiment of the present invention, and FIGS. 3a and 3 b show two examples of shapes in which the exhaust pipe is crimped and crushed in the manufacturing method of this invention. FIG. 4 is a side view, FIG. 4 is a sectional view showing a general magnetron, and FIG. 5 is a circuit diagram showing the connection state of lead wires during exhaust of the conventional magnetron. 1... Anode cylinder, 2... Vane, 7... Exhaust pipe, 11... Antenna lead.

Claims (1)

[Claims] 1. A plurality of vanes are fixed inside the anode cylinder, an antenna lead is led out from one of the vanes and inserted into an exhaust pipe, and the exhaust pipe is connected to a vacuum exhaust device, and the anode cylinder is connected to the anode cylinder. In a method of manufacturing a magnetron in which exhaust is performed while maintaining the exhaust pipe at ground potential, the exhaust pipe is slightly caulked and crushed, and the anode cylinder is brought into electrical short-circuit contact with the antenna lead, thereby bringing the anode cylinder to ground potential through the exhaust pipe and the antenna lead. A method for producing a magnetron, which is characterized by passing through an exhaust process while maintaining the temperature, and then chipping off the exhaust pipe at the final stage of the exhaust process.