Method and device for mounting a rotating member
A rotating anode is mounted on a shaft of an X-ray tube by means of a ring. The ring allows expansion and reduces the hyperstatic state of the assembly. The ring has the shape of a diabolo, preferably that of a hyperboloid structure generated by revolution. The ring dampens vibration phenomena in a shaft bearing the rotating anode and reduces noise-creating phenomena.
This application is a divisional application of U.S. application Ser. No. 10/825,512 filed Apr. 15, 2004, which is hereby incorporated by reference in its entirety, and claims the benefit of a priority under 35 USC 119(a)-(d) to French Patent Application No. 03 50113 filed Apr. 17, 2003, the entire contents of which are hereby incorporate by reference.
BACKGROUND OF THE INVENTIONThe present invention is directed to a method and a device for mounting a rotating member. In particular, the present invention is directed to a source of radiation and, more particularly the mounting of a rotating anode in an X-ray tube and a method for manufacturing a part of this device. The rotating anode tubes are X-ray emitting tubes used mainly in mammography, although their use can be envisaged in other fields of radiology, especially tomodensitometry. In mammography, the conditions of the examination require the patient to place his or her breast on a breast-support tray. An X-ray emitting device, generally placed on a vertical column that bears the breast-support tray, is placed close to the patient's head. This proximity not only dictates particularly strict constraints of electrical installation, but also requires that the X-ray tube should not vibrate, so as not to inconvenience the patient during an examination that moreover is a stressful experience. These vibrations are noisy. In general, they are especially present as the sheathing of the tube is metallic and is itself sensitive to vibrations.
In practice, an X-ray tube with rotating anode has an anode rotating at high speed. The anode is positioned so that, on one side, it faces a cathode and, on the other, a window that is vacuum-tight but enables the passage of the emitted X-rays. The rotation of the anode is prompted by a rotor working by means of bearings. The rotor drives the rotating anode to which it is fixedly joined. Despite all the efforts made to balance this rotating part, there are imbalances that contribute to making the entire tube vibrate. The shaft is fixed in the tube by being fixed at both its ends. The shaft is thus fixed to a first structure, namely a first part of the sheathing of the tube, on one side and to a second structure, namely a second part of the sheathing, on the other side. The two structures are then linked to each other. If the linking of the structures is rigid, such an assembly leads to a hyperstatic condition in the holding of the shaft and, at a mechanical level, it entails breaks that are unacceptable. To overcome this drawback, one end of the shaft is mounted in a structure that is, in principle, the lightest and/or least rigid type of structure, using a ring that allows certain degrees of freedom. The rings used, which generally have a squirrel-cage shape, are elastic but have the drawback of not being reusable. Indeed, the rings are deformed because they have to be force-fitted when mounted in a structure, before the insertion of a shaft end. Furthermore, the insertion of the rings themselves requires an exertion of considerable force during assembly.
The value of the rings is that they resolve the problems related to the hyperstatic condition and furthermore allow the expansion caused by the heating of the anode. However, they do not resolve the problem of vibrations, which continue to be a source of problems for the patient and may even lead to faulty precision in the radiological images acquired.
BRIEF DESCRIPTION OF THE INVENTIONAn embodiment of the invention is directed to the problems of vibration and the re-utilization of the rings. In an embodiment of the invention the rings are diabolo-shaped rings. The diabolo-shaped rings are supported in a housing in the structures by means of end crowns. They hold the shaft inside the diabolo by means of a narrowed central part of the diabolo. In an embodiment by making the diabolos in an open shape, the ring can be adapted to the manufacturing tolerance values of the bores that receive the ends of the shaft. The insertion of the rings therefore no longer necessitates any excessive force fitting. The rings can consequently be re-utilized. In an embodiment of the invention the diabolo is hyperboloid shape.
An embodiment of the invention is directed to a method for making the diabolo-shaped rings so that the cost of their manufacture is reduced to the minimum. In an embodiment of the method, the diabolo shape is a hyperboloid shape.
An embodiment of the invention is a device for mounting a rotating anode in an X-ray tube comprising, in a first structure, a bore, a ring housed in this bore, with one end of a shaft of the rotating anode inserted in this ring, wherein the ring comprises a diabolo shape generated by revolution about an axis of the shaft.
An embodiment of the invention is a method for the manufacture of a diabolo comprising: forming a diabolo from a cylinder; forming beams in one wall of the diabolo wherein the beams being could be inclined.
BRIEF DESCRIPTION OF THE DRAWINGSAn embodiment of the invention will be understood more clearly from the following description and the accompanying figures. The figures are given purely by way of an example and in no way restrict the scope of the invention. Of these figures:
FIGS. 2 to 6 exemplify the making of a hyperboloid structure generated by revolution fulfilling the role of a diabolo;
FIGS. 7 to 9 illustrate the effects of the mounting of the diabolo in the mounting device;
In an embodiment of the invention, the ring 5 has a diabolo shape generated by revolution about an axis that is the axis 7 of the shaft 3. This shape is shown in
Several methods for manufacturing the diabolo-shaped ring of the invention are possible. By way of example, dimensions and shapes of the ring shall be specified with reference to
Once the cutting-out operations have been performed, as shown in
For the making of an open ring, make an aperture 20 (
Another procedure may comprise the use of a parallelogram-shaped plate 24 rather than that of a rectangular plate 11. In this plate 24, the slots 25 are inclined, as also the beams 26, relative to the normal to the lintels 14 and 15 (shown in
In one example, the inclination of the beams 26 on the lintels 14 and 15 may be about 50° plus or minus 10°. The mold that receives the ring of
In another embodiment for making the diabolo, it is also possible to start from a thick cylinder, for example with a thickness 28, as shown in
The molding method and the hollowing-out method do not necessarily lead to a hyperboloid diabolo. The twisting method leads to it naturally.
Whatever the method of manufacture used, it leads to the positioning of beams 10 inside the diabolo. These beams set up a narrowing of the available space within the diabolo while they are also attached, on both sides of this diabolo, to elements having circumferences of greater diameter. To this effect,
In the embodiment shown in
The opening of the ring enables the insertion of the ring 5 into the bore 37 made in the structure 6. The narrowing of the aperture 34 and/or the aperture 35 enables insertion and, furthermore, wedging. Furthermore, the narrowing makes it possible to accept a greater tolerance in the making of the bore that receives the end of the shaft 3 in the structure 6.
As shown in
As described an embodiment of the method may comprise: in a thin plate, cut-out slots are made, interposed with parallel beams, these parallel beams being held together at their ends by lintels; the lintels and the beams are shaped around a circular chuck with an axis perpendicular to the lintels; and the circularly shaped lintels are twisted, with respect to each other, about an axis collinear with the axis of the chuck
As described an embodiment of the method may comprise: in a thin plate, cut-out slots are made, interposed with parallel beams, these parallel beams being held together at their ends by lintels, the beams being inclined in relation to a direction perpendicular to the lintels; the thin plate thus cut out is deformed by being forced into a mold with a shape generated by revolution, with an axis of revolution orthogonal to the directions of the lintels; and the mold having an embossment in a central part between the ends that receive the lintels.
One skilled in the art may make or propose various modifications to the structure/way and/or function and/or result and/or steps of the disclosed embodiments and equivalents thereof without departing from the scope and extant of the invention.
Claims
1. A method for the manufacture of a diabolo comprising:
- forming slots in a plate, the slots being interposed with non-inclined parallel beams, the parallel beams being held together at their ends by lintels;
- shaping the plate around a circular chuck with an axis perpendicular to the lintels; and
- twisting the circularly shaped lintels, with respect to each other, about an axis collinear with the axis of the chuck to incline the beams.
2. A method for the manufacture of a diabolo comprising:
- forming slots in a plate, the slots being interposed with parallel beams, the parallel beams being held together at their ends by lintels, the beams being inclined in relation to a direction perpendicular to the lintels;
- deforming the formed plate by being forced into a mold with a shape generated by revolution, with an axis of revolution orthogonal to the directions of the lintels; and
- the mold having an embossment in a central part between the ends that receive the lintels.
3. The method according to claim 1 wherein the plate is a parallelogram.
4. The method according to claim 2 wherein the plate is a parallelogram.
5. The method according to claim 1 wherein the plate is rectangular.
6. The method according to claim 1 wherein the formed slots are straight between the lintels.
7. The method according to claim 2 wherein the formed slots are straight between the lintels.
8. The method according to claim 1 wherein the formed slots are rectilinear between the lintels.
9. The method according to claim 2 wherein the formed slots are rectilinear between the lintels.
10. The method according to claim 1 wherein the formed slots are oriented at a right angle to the direction of the lintels.
11. The method according to claim 2 wherein the formed slots are oriented at a right angle to the direction of the lintels.
12. The method according to claim 1 wherein an aperture is formed in at least one diametrically opposite parts of the lintels.
13. The method according to claim 2 wherein an aperture is formed in at least one diametrically opposite parts of the lintels.
14. The method according to claim 1 wherein an aperture is formed in two diametrically opposed parts of the lintels.
15. The method according to claim 2 wherein an aperture is formed in two diametrically opposed parts of the lintels.
16. A method for the manufacture of a diabolo comprising:
- forming a diabolo from a cylinder by removing portions of the cylinder; and
- forming beams in a wall of the diabolo, the beams being inclined.
17. The method according to claim 1 wherein the inclination of the beams is about 50° relative to an axis of the diabolo.
18. The method according to claim 2 wherein the inclination of the beams is about 50° relative to an axis of the diabolo.
19. The method according to claim 3 wherein the inclination of the beams is about 50° relative to an axis of the diabolo.
20. The method according to claim 5 wherein the inclination of the beams is about 50° relative to an axis of the diabolo.
21. The method according to claim 6 wherein the inclination of the beams is about 50° relative to an axis of the diabolo.
22. The method according to claim 8 wherein the inclination of the beams is about 50° relative to an axis of the diabolo.
23. The method according to claim 10 wherein the inclination of the beams is about 50° relative to an axis of the diabolo.
24. The method according to claim 12 wherein the inclination of the beams is about 50° relative to an axis of the diabolo.
25. The method according to claim 14 wherein the inclination of the beams is about 50° relative to an axis of the diabolo.
26. The method according to claim 16 wherein the inclination of the beams is about 50° relative to an axis of the diabolo.
27. The method according to claim 17 wherein the inclination of the beams is 50°±10°.
28. The method according to claim 17 wherein the inclination of the beams is 50°±5°.
29. The method according to claim 1 wherein the diabolo shape has twist angle greater than or less than 50°.
30. The method according to claim 2 wherein the diabolo shape has twist angle greater than or less than 50°.
31. The method according to claim 16 wherein the diabolo shape has twist angle greater than or less than 50°.
32. method according to claim 1 wherein the diabolo has a hyperboloid shape.
33. method according to claim 2 wherein the diabolo has a hyperboloid shape.
34. method according to claim 16 wherein the diabolo has a hyperboloid shape.
35. The method according to claim 32 wherein the hyperboloid shape has an inner curvature diameter that is less than the initial diameter.
Type: Application
Filed: Oct 30, 2006
Publication Date: May 10, 2007
Inventors: Xavier Lacherade (Versailles), Caroline Le-Pierrard (Le Mesnil Saint Denis), Jean-Luc Josse (Neulilly Plaisance)
Application Number: 11/589,467
International Classification: B21D 43/28 (20060101);