JPS58119142A - Rotary anode - Google Patents

Abstract

PURPOSE:To prevent generation of an interpositional slip at the fixing part of a target and a prop of an X-ray tube rotary anode. CONSTITUTION:In a junction part 9, platinum plating is performed on a target seat surface of a prop 4 and on an axial surface making contact with the inside of the target hole, in order to let the platinum diffuse into molybudenum of the target and the prop. In this case, when the target temperature exceeds 1,000 deg.C, a crack is generated in a crystaline interface of molybudenum of the target owing to platinum diffusion. However, when the emissivity of the target surface is rendered more than 0.6 by means of blackening treatment, and the like, the target temperature is suppressed to about 800 deg.C while the temperature at the platinum diffusion junction part between the target and the prop is also suppressed to 600-650 deg.C, thus generating no intergranular crack of molybudenum owing to platinum diffusion.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a rotating anode for an X-ray tube in which mutual positional deviation does not occur at fixed portions of a target and a support.

Figure 1111 shows the vicinity of the fixed part between the target and the support of a conventional xswwm anode, where l is the nut, 2 is the spot, 3 is the target, 4 is the support, 5 is the fixed housing, 6 is the bearing, and 7 is the rotating shaft. , '8 is a screw.

However, in this conventional fixing method, the target heats up due to the impact of the high-speed electron flow, and the temperature rises extremely rapidly and thermally expands. Tighten! This will cause it to loosen. It is unavoidable that there is a difference in diameter, that is, a gap, even if it is small, between the diameter of the pillar and the hole at the center of the target. Therefore, if the force with which the nut tightens the target at the fixing part loosens, a slight displacement will occur between the column and the target. When assembling the rotating anode (target, support, etc.),
Since the balance machine is used to balance the dynamo structure, the initial residual unbalance is small, but if a positional shift occurs at the identification part between the support and the target as described above, the target is heavy and has a large diameter, so the positional shift will occur. Although the dimensions themselves are small, they have a large effect on vibration during rotation.

The noise becomes so loud that the target deflection reaches 200 to 300μ after 10,000 operations, and bearing damage progresses rapidly, making it unusable and ending its life.

The purpose of this project is to provide a rotary anode for XII tubes that has a 5K resistance at the fixing part between the target and the support, so that the mutual positional shift between the target and the support does not occur even after long-term use. In order to achieve JkrR, in the present invention, platinum plating is applied to the contact surface of the support column that supports the target,
This platinum was diffused to the target side through the contact surface, and the Targuts F and the support were fixed in contact with each other via the platinum layer, and the fixing portion was heated for 5K so that no deviation occurred at the fixed part even if the number of operations was repeated.

Reference numeral 21m indicates the main part of the present example, 9 indicates a platinum diffusion rigging part, and other symbols are the same as in FIG. In this platinum diffusion welding, for example, platinum plating is applied to the target seating surface of the support column 4 and the rings in contact with the inner surface of the hole in the target, and the platinum is transferred to the target F by heat conduction, heating, and temperature rise from the target during the exhaust process. It can be diffused into the molybdenum of the strut. In this case, the target temperature is 1,00
If the temperature exceeds 0° C., cracks will occur at the grain boundaries of molybdenum in the target due to platinum diffusion. However, if the target cost is made to have an emissivity of 0.6 or more by blackening treatment, etc., the target temperature can be suppressed to about 800℃, and the temperature of the platinum diffusion joint between the pillar and the support can be reduced to 600 to 650℃.
Therefore, grain boundary cracks in solidendenum due to platinum diffusion do not occur.

As explained above, according to the present invention, it is possible to prevent the occurrence of positional deviation at the fixed part between the target and the column of the rotating anode, and also to prevent an increase in the unbalance of the rotating anode caused by this deviation. The roof is lengthened.

[Brief explanation of drawings]

FIG. 1 is a close-up view of a fixing portion between a target and a column of a conventional Xl1I tube, and FIG. 2 is a diagram showing a main part of an embodiment of the present invention. 3...Target, 4...Strut, 9...Platinum diffusion joint.

Claims (1)

[Claims] The target is used to support the center of the target at one end, and the other end supports the target with the support connected to the 1-turn WIII. Platinum plating was applied to the contact surface of the supporting part, and this platinum was diffused to the target side through the contact surface, and the target and support column were bonded and fixed via the platinum layer.vl#
Rotating anode of XII tube that makes mold.