JPS60127637A - Magnetron anode structure - Google Patents

Abstract

PURPOSE:To mitigate the stress concentration due to the generated heat by forming strap rings connecting alternate vanes provided on an anode cylinder constituting a resonance cavity with R sections provided at intersections of projections and ring sections. CONSTITUTION:A magnetron anode structure is formed with an anode cylinder 1 constituting a resonant cavity, multiple vanes 2 arranged radially inside and provided with grooves on the end surface in the cylinder axis direction, and strap rings 3, 4 arranged in the vane grooves and connecting alternate vanes. In this case, the maximum stress applied to center sections 3c, 4c, and intersections 3b, 4b of the strap rings 3, 4 by on/off actions of the magnetron is mitigated by adjusting the thickness, etc. of 3c, 4c and providing R sections 3e, 4e on 3b, 4b. Acordingly, the life fatigue time determined by the thermal stress can be improved remarkably.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to magnetron anode structures, and more particularly to improvements in strap rings.

[Background of the invention]

As shown in FIG. 1, the magnetron anode structure that has been widely used in the past includes an anode cylinder 1 constituting a cavity resonator, and grooves 2a arranged radially inside the anode cylinder 1 and formed on the end face in the axial direction of the cylinder. An even number of vanes 2 are provided, and a strap ring 3.4 is provided in the groove 2apg of the vane 2 and connects every other vane 2 electrically.

To manufacture the anode cylinder 1 and the vane 2, the anode cylinder 1 and the vane 2 are integrally formed by hobbing a bottle of oxygen-free copper, and then a resin or the like is filled between the vanes 2, and a groove 2a is formed on the cylinder shaft by lathe processing. Provided at the upper and lower ends of the direction. After such finishing processing, the resin is removed. On the other hand, the strap ring 3.4 is manufactured by stamping a plate material of oxygen-free steel, and simultaneously molding the inner strap ring 3 and the outer strap ring 4 having the rings 3a, 4a and the protrusions 3b, 41). These strap rings 3.4 are then plated with silver.

Therefore, the strap ring 3.4 is assembled to the fin 2 provided on the anode cylinder 1. This assembly consists of groove 2 of vane 2.
The protruding parts 3b and 4 of the strap ring 3.4 up to the middle stage of a.
b with a slight tightening margin, and placed in a reducing atmosphere furnace at approximately 800°C to form a silver-copper solder between the silver plating layer of the strap ring 3.4 and the copper material of the vane 2 and the strap ring 3.4. The brazing will definitely stick. When the magnetron anode structure configured in this way is used as a magnetron, a cathode (not shown) serving as a heat source is disposed on the central axis of the anode cylinder 1, and cooling fins (not shown) are provided on the outside of the anode cylinder 1. ) is installed.

By the way, when the magnetron anode structure has a configuration in which force is
The strap rings 3 and 4 thermally expand in the direction of arrow C.
Thermal expansion occurs in the direction of Therefore, magnetron ON/OF
As the F action is repeated, the vane 2 and the strap ring 3.4 repeatedly expand and contract in opposite directions, so the strap ring 3.4 is subjected to stress cycling. Then,
Areas with high stress may cause cracks, leading to damage.

When we investigate magnetrons in which the strap rings 3 and 4 are damaged due to life fatigue, we often find that the center portions 3C14C and 3C of the rings 3a and 4a shown in Figure 1 (al)
Cracks have occurred at the intersections 3d and 4d between a and the protrusions 3b and 4b. This is the center part 3C14C and the intersection part 3d
, 4d indicates that the maximum stress occurs.

Therefore, conventionally, for the central part 3C14C,
As shown in Japanese Patent No. 56564, the shape of the strap ring is made into a non-circular shape that extends outward in the radial direction, and the wall thickness in the radial direction of the center part is reduced to the extent that it does not impair the flexibility. The strap ring is designed to have a longer lifespan by taking measures such as tightening it to relieve stress in the central portion 3C14C.

However, the actual situation is that no suitable means is available for the intersection points 3d and 4d, so the above means have not been applied.

[Purpose of the invention]

An object of the present invention is to provide a magnet (
・Providing a long anode structure.

[Summary of the invention]

In order to achieve the above object, the present invention provides a strap ring with a groove formed at the intersection of the radially extending protrusion of the vane and the ring portion of the strap ring for connection to the groove of the vane. It is characterized by what it did.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to FIG. The same members and parts as in Figure 1 are given the same reference numerals.
C.Explain. The strap 3.4 has ring parts 3a, 4.
Eleven portions 3e and 4e are formed at the intersections 3d and 4d (see FIG. 1) of the protrusions 31) and 4b.

Figure 3 shows the time required for the inner strap ring 3 to reach fatigue failure (,
FIG. Here, the inner strap ring 3 was regarded as a curved beam between the connecting portions (ring portions 3a) with the vanes 2, and the life time was calculated assuming that repeated stress is applied from the perspective of material mechanics. The life time is ON -O
The FF cycle was set to 2 minutes, and the ON time was set. In addition, the vane 2 has a heat input of 600 W, a thickness of 1.6 mm, and has 12 blades, and the inner strap ring 3 has an inner diameter of 14 mm and a wall thickness in the radial direction of the ring part 3a of 0.65 mm.
I responded to every other person I contacted.

As a result, the larger the R dimension, the more effective it is, but 0, 4
It was found that the life time becomes almost saturated when the force is about 1 mm.

In this way, the ring parts 3a, 4a of the strap 3.4 and the protruding part 3+), the it part 3e at the intersection parts 3d, 4d of 4b,
By increasing the IT dimension of 4e and realistically making the R dimension more than half of the radial wall thickness of the strap ring 3.4, stress concentration can be alleviated and the magnetron operation can be turned 0N-OFF. The life fatigue time, which is determined by the thermal stress ζ applied by ζ, can be significantly improved.

〔Effect of the invention〕

According to the present invention, stress concentration at the intersection between the protruding portion of the strap ring and the ring portion can be alleviated, and the life fatigue time can be improved.

[Brief explanation of the drawing]

FIG. 1 shows a conventional magnetron anode structure, (al is a plan view, (b) is an enlarged cross-sectional view taken along the line A-A in (a), and FIG. 2 shows an embodiment of the magnetron anode structure according to the present invention. The plan view shown in FIG. 3 is a diagram showing the relationship between the 8 dimensions of the 8 parts of the strap ring and the life fatigue time. 1...Anode cylinder, 2...Vane, 2a...Groove, 3.4 ...Strap ring, 3a, 4a...
Ring part, 3b, 4b... protruding part, 3d, 4d...
・Intersection part, 3e, 4e...8 parts.

Claims (1)

[Claims] An anode cylinder constituting a cavity resonator, a plurality of vanes arranged radially inside the anode cylinder and having grooves on the end face in the axial direction of the cylinder, and one vane arranged in the groove of the vane. In the McNetron anode groove body, the strap ring includes a protrusion extending in the radial direction of the vane for connection to the groove of the vane, and a ring of the strap ring. 1. A magnetron anode structure characterized by forming a recessed part at the intersection with the part.