JPS61139700A - Production of bearing ball for x-ray tube - Google Patents

Abstract

PURPOSE:To coat uniformly and securely a solid lubricant on plural balls for a bearing for an X-ray tube by holding the balls in the meshes of a mesh electrode so as not to contact with eachother and plating the lubricating agent thereto while moving the balls. CONSTITUTION:The plural bearing balls 11 made of steel are held in the meshes 21 of the cage-shaped mesh electrode 16 constituted of copper mesh wires 22 and are dipped into a lead plating liquid 15 in a plating bath vessel provided with a lead electrode plate 14 on the inside surface of an outside box 13. The electrode 16 is connected to the negative pole of a DC power source 18 and the plate 14 to the positive pole thereof via a switch 17. Each mesh of the elecrtrode 16 is made into a rectangular or rhombic shape and is so set that the balls 11 held therein dot contact with each other. The balls 11 are subjected to lead plating while the balls are moved by oscillating the electrode 16 in an arrow direction at every prescribed time. The bearing balls for the rotary anode type X-ray tube coated with the lead plating layer as the solid lubricating agent with the substantially high adhesive force to a uniform thickness are thus obtd.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to an improvement in a manufacturing method for coating a bearing used in a rotor of a rotating anode X-ray tube with a solid lubricant.

[Technical Background of the Invention and Problems Therewith] As is well known, the rotor of a rotating anode X-ray tube rotates the anode target at a high speed of, for example, 110,000 rpm using ball bearings. This ball bearing has a plurality of balls between the inner and outer races, and these balls are coated with a conductive solid lubricant such as lead, silver, or molybdenum disulfide. For example, when a ball is coated with lead to a predetermined thickness, it is generally known that barrel plating is used. This involves attaching a copper plate to the barrel as an electrode, placing a steel ball in a bath of lead plating solution, and plating by passing an electric current through it. In this case, plating is performed while the barrel is rocked or rotated, but in this conventional method, there are few opportunities for the ball to come into contact with the electrode plate, and there are few contact areas, so the adhesion of lead tends to be weak. Furthermore, since the balls overlap each other, it is difficult to obtain a uniform plating thickness over the entire surface of the ball.

[Purpose of the invention]

The present invention provides a method for manufacturing a bearing ball for a rotating anode type X-ray tube, in which the thickness of the conductive solid lubricant coating on the bearing ball can be formed uniformly, and the adhesive force can be sufficiently strong.

[Summary of the invention]

In this invention, a mesh electrode is used as an electrode for accommodating a large number of poles, and each pole can be held in a plating tank at intervals so that the poles do not come in contact with each other. - Plating the solid lubricant onto the ball by moving the ball
This is a method of manufacturing bearing balls for wire tubes.

[Embodiments of the invention]

Examples thereof will be described below with reference to the drawings.

Identical parts are designated by the same reference numerals.

According to the embodiment shown in FIGS. 1 to 3, a lead lubricant layer 1 is formed on the entire surface of the steel bearing pole 11 as shown in FIG.
A method of covering No. 2 by plating will be explained.

A lead electrode plate 14 is provided on the inner surface of an outer box 13 constituting a plating bath, and the inside thereof is filled with a lead plating solution 15.

A basket-shaped mesh electrode is placed in this bathtub and is vibrated at predetermined time intervals as indicated by arrow F by a suitable drive device (not shown). Remove this cage-shaped mesh electrode! A negative pole of a DC power supply 18 is connected to the switch 17 via a switch 17, and a positive pole is connected to the lead electrode plate 14.

As shown in FIGS. 2 and 3, the mesh electrode 16- is composed of a copper wire 22 in which each mesh 21 is in the shape of a rhombus, and is dimensioned so that the balls 11 held in each mesh 21 do not come into contact with each other. It is formed like a mesh.

The mesh electrode unit may be made of a conductive material such as aluminum in addition to copper.

For plating, turn on the switch 17 and apply a current of, for example, 0.35 A for 1 minute, then turn the switch OFF.
Make it F? - Shake or vibrate the two-mesh electrode embryo in the direction of arrow F so that the contact point between the electrode and the mesh wire moves. Of course, in this case, make sure that the balls are held in each mesh so that they do not overlap again after moving to another mesh. Then, turn on the switch again to pass the current. Repeat this operation several times to complete plating.

As a result, each ball is stably held within each rectangular mesh of the mesh electrode, and the contact point and contact area with the mesh wire cutting wheel are slightly different from each other. - Since the balls do not come into contact with each other, a lead plating layer with a uniform thickness and sufficient adhesion can be formed over the entire surface of the ball. Therefore, the pole bearing that becomes part of the anode current path of the X-ray tube is stable and can sufficiently withstand high-speed rotation for a long time.

Note that the present invention is not limited to the materials of the above-mentioned embodiments as long as the material of the balls and the solid lubricant have conductivity, and various conductive materials can be used.

〔Effect of the invention〕

According to this invention, it is possible to reliably form a solid lubricant coating layer with a uniform thickness and strong adhesion over the entire surface of the pair link reel.

[Brief explanation of drawings]

FIG. 1 is a schematic cross-sectional view showing an example of a device used to carry out the present invention, FIG. 3 is a cross-sectional view of a main part thereof, and FIG. 4 is a cross-sectional view of a completed bearing pole. 11...Bearing ball, 12...Lubricant i, 1
3... Outer box (plated bathtub), 14... Electrode plate, mutual
...Mesh electrode, 21...Mesh, 22...Mesh wire. Applicant's representative Patent attorney Takehiko Suzue Figure 1 Figure 2 Figure 31 Figure 4 Commissioner of the Patent Office Manabu Shiga 1, Indication of the case Patent application No. 1982-260143 2, Name of the invention Bearing ball for X-ray tube 3. Relationship with the case of the person making the amendment Patent applicant (307) Toshiba Corporation 4, Agent 7, Contents of the amendment (1) In the specification attached to the application, on page 6, line 7, “ Third
"Fig." has been corrected to "Fig. 2 and Fig. 3."

Claims (2)

[Claims] (1) In a method of coating a plurality of balls of a bearing used in a rotor of a rotating anode X-ray tube with a conductive solid lubricant, the plurality of balls can be held at intervals in a plating bath so that they do not come into contact with each other. A method for manufacturing a bearing ball for an X-ray tube, which comprises using a mesh electrode, and moving the ball at predetermined time intervals while holding the ball in the mesh of the mesh electrode to coat the ball with a lubricant by plating. (2) The method for manufacturing a bearing ball for an X-ray tube according to claim 1, wherein the mesh electrode has each mesh having a rectangular or rhombic shape.