JP2009252648A - Rotating anode x-ray tube device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rotary anode type X-ray tube device which can improve a heat emission property and has high reliability over a long period. <P>SOLUTION: The rotary anode type X-ray tube device includes a vacuum envelope 11, integrated with an anode target 15 and rotatably formed, a housing 3 for rotatably retaining the vacuum envelope 11, a circulation passage 8 for circulating a cooling medium, a cathode 13, a support member 14 for supporting the cathode 13, a bearing mechanism and a vacuum seal mechanism, and rotation drive unit. The support member 14 has a high-voltage wiring section 14b, a high-voltage supply terminal 14c, and a side face 14f, located in the housing 3 and arranged with a heat transmission acceleration section 16 which is in close contact with the cooling medium 7. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a rotary anode X-ray tube apparatus, and more particularly to a rotary anode X-ray tube apparatus that can improve heat release characteristics.

  Conventional rotary anode X-ray tube apparatuses are roughly classified into the following two types.

  (1) Type 1: Rotating anode type X-ray tube device includes a rotating anode type X-ray tube in which a rotatable anode target is accommodated in a vacuum envelope, a housing for accommodating a rotating anode type X-ray tube, etc. In order to release the heat generated by the anode target or the like, a circulation path for circulating a cooling medium is provided inside the anode target (see, for example, Patent Document 1 and Patent Document 2).

  Since the heat of the anode target is transferred to the cooling medium through a short heat path, it is possible to improve the heat release characteristics generated by the anode.

  (2) Type 2: A rotary anode X-ray tube device is rotatable about an axis, a part of which is an anode target and a vacuum chamber which is a vacuum chamber, and a vacuum envelope around the axis Means for rotating the vessel, a cathode mounted in a vacuum chamber for generating electrons and focusing them in a region outside the axis of the anode target, and a housing (see, for example, US Pat. Thru | or patent document 6). A high voltage is supplied to the cathode from the outside of the housing.

Since the heat of the anode target is transferred to the cooling medium through a short heat path, it is possible to improve the heat release characteristics generated by the anode.
Japanese Patent Publication No. 5-27205 JP 2006-54181 A Japanese Patent No. 2539193 French Patent No. 2599555-A1 Japanese Patent No. 2929506 US Pat. No. 6,396,901

  According to the rotary anode X-ray tube device configured as in (1), when the thermal load of the rotary anode X-ray tube increases, the required cooling performance can be sufficiently obtained for the reasons described below. There may not be.

  a) The higher the difference between the moving speed of the rotating anode target back surface and the moving speed of the fluid in contact therewith (relative moving speed), the higher the heat transfer coefficient at the contact interface. This is because the moving speed does not depend much on the rotation speed of the anode target, and almost depends only on the flow rate of the cooling medium. This is because the cooling medium also rotates with the rotation of the anode target (in the case of Patent Document 2).

  b) Since the cooling medium is forcibly driven by a circulation pump through a narrow flow path provided in a thin shaft or target having a high fluid resistance, there is a limit to increasing the flow rate of the cooling medium.

  c) In addition, the structure in which the flow path is provided inside the anode target causes an increase in manufacturing cost due to its complexity. On the other hand, in the structure shown in FIG. 5 of Patent Document 2, such a flow path is not provided inside the anode target. However, when such a simple anode target structure is adopted, the cooling performance is further deteriorated. Resulting in.

  According to the rotary anode type X-ray tube device configured as in (2), when the thermal load of the rotary anode type X-ray tube becomes large as in (1), the cooling required for the following reasons. In some cases, sufficient performance cannot be obtained.

  d) First, it is difficult to use an aqueous cooling medium having a high cooling performance, and it is necessary to use an insulating oil having a poor cooling performance as the cooling medium. That is, the space in which the cooling medium exists and the cathode potential exposure space are in communication with each other. Therefore, when the aqueous cooling medium is used, the withstand voltage performance of the cathode portion is likely to deteriorate due to the influence of water vapor.

  e) Also, due to the structure of providing a sliding current supply mechanism for supplying current from the source outside the vacuum chamber to the cathode through the wall portion of the vacuum envelope, a grid electrode for making the focal point multipolar and pulsing is provided. It becomes difficult to increase the functionality such as adding. This is because it is necessary to increase the number of sliding energization mechanisms as these functions become higher, and as a result, one or more sliding portions will be provided at locations where the peripheral speed is large outside the axis. . In such a case, the life of the sliding energization mechanism is shortened due to wear of the sliding portion.

  An object of the present invention is to provide a rotary anode type X-ray tube apparatus that can improve heat release characteristics and has high reliability over a long period of time.

A rotary anode type X-ray tube apparatus according to an aspect of the present invention is:
A vacuum envelope integrated with the anode target and formed to be rotatable;
A housing that houses at least the vacuum envelope and rotatably holds the vacuum envelope;
A circulation path formed in the housing and in which a cooling medium circulates in the vicinity of at least the anode target;
A stationary cathode housed in the vacuum envelope and stationary;
A support member for supporting the cathode;
A bearing mechanism and a vacuum seal mechanism provided between the vacuum envelope and the housing or a fixed body fixed to the housing;
A rotation driving device for rotating the vacuum envelope,
The support member is
A high-voltage wiring portion electrically connected to the cathode;
A high voltage supply terminal electrically connected to the high voltage wiring portion and exposed outside the housing;
A side surface located in the housing, surrounding the high voltage wiring portion, and provided with a heat transfer promoting portion in contact with the cooling medium;
It is characterized by having.

A rotating anode type X-ray tube apparatus according to another aspect of the present invention is:
An anode target that generates X-rays when electrons collide;
An electron emission source for emitting electrons toward the anode target;
A vacuum envelope for holding the anode target and the electron emission source under a predetermined reduced pressure;
A housing containing the vacuum envelope and hermetically sealed so that a coolant can circulate between the vacuum envelope;
A support member for fixing the electron emission source to the housing;
A holding member for rotatably holding the vacuum envelope in the housing;
A vacuum seal member that is positioned between the vacuum envelope and the holding member and that allows the vacuum envelope to rotate within the housing while maintaining the pressure within the vacuum envelope;
The support member is
A high-voltage wiring portion electrically connected to the electron emission power source;
A high voltage supply terminal electrically connected to the high voltage wiring portion and exposed outside the housing;
A side surface located in the housing, surrounding the high voltage wiring portion, and provided with a heat transfer promoting portion in contact with the cooling medium;
It is characterized by having.

  According to the present invention, it is possible to provide a rotary anode type X-ray tube apparatus that can improve the heat release characteristics and has high reliability over a long period of time. In addition, since a heat transfer promoting portion that contacts the cooling medium (cooling liquid) is provided on the side surface of the support member, the heat from the cathode is dissipated into the cooling medium to lower the temperature of the high voltage connector connected to the support member. Insulation of the high voltage connector can be ensured over a long period of time.

  Hereinafter, a rotary anode type X-ray tube apparatus according to a first embodiment of the present invention will be described in detail with reference to the drawings.

  As shown in FIG. 1, an X-ray tube apparatus 1 is incorporated in, for example, an X-ray image diagnostic apparatus or a nondestructive inspection apparatus, and emits X-rays to an object, that is, a non-inspection object. The X-ray tube device 1 includes a housing 3 and an X-ray tube main body (rotary anode type X-ray tube) 5. The X-ray tube body 5 is accommodated in the housing 3 and can emit X-rays having a predetermined intensity in a predetermined direction.

  The X-ray tube main body 5 is accommodated in a predetermined position of the housing 3 via the coolant 7. The coolant 7 is, for example, a non-oil-based coolant (water-based coolant) whose main component is water and whose electrical conductivity is controlled to be less than a predetermined level. As the cooling liquid 7, a cooling medium having a conductivity set to 1 mS / m or less is used in order to ensure insulation against low voltage and reduce corrosiveness to metal parts. The cooling medium is mainly an aqueous medium in which a predetermined amount of water or glycol is mixed. Moreover, as glycols mixed with water as a cooling medium, for example, ethylene glycol, propylene glycol, or the like can be used.

  The coolant 7 is in contact with an inert gas between the housing 3 and the vacuum envelope 11 and the inert gas is dissolved in a saturated state in advance. Here, the coolant 7 is saturated with helium (He) gas which is an inert gas.

  The X-ray tube main body 5 includes a vacuum envelope 11, a cathode (thermoelectron emission source) 13, and an anode target (rotary anode, anode) 15. The vacuum envelope 11 is grounded by being in contact with a grounding electrode 9 provided through a predetermined position of one end of the housing 3.

  The inside of the vacuum envelope 11 is maintained at a predetermined degree of vacuum. Inside the vacuum envelope 11, a cathode 13 and an anode target 15 are provided. The vacuum envelope 11 holds the cathode 13 and the anode target 15 under a predetermined reduced pressure. A cathode 13 is provided independently of the vacuum envelope 11. The anode target 15 is provided inside the vacuum envelope 11 so as to be rotatable integrally with the vacuum envelope 11. The anode target 15 emits X-rays having a predetermined wavelength when the electrons emitted from the cathode 13 collide with each other.

  The vacuum envelope 11 is held by a magnetic fluid vacuum seal member 53 as a vacuum seal mechanism and a bearing (rolling bearing, ball / roll bearing) member 55 as a bearing mechanism. The magnetic fluid vacuum seal member 53 is provided at a predetermined position on the inner peripheral surface of the cylindrical fixing portion 51 provided at a predetermined position of the housing 3. The bearing member 55 is provided at a predetermined position of the fixed portion 51 and closer to the flow path of the coolant 7 than the magnetic fluid vacuum seal member 53. The cylindrical fixing portion 51 is concentrically (coaxially) fixed to the vacuum envelope holding portion 59 of the housing 3 via an electrically insulating support member 57.

  The cathode 13 is supported by a support member 14. The support member 14 has a cylindrical and electrically insulating cathode holder 14a. A fixing member 63 fixed to the outer peripheral surface of the cathode holder 14 a and a predetermined region inside the cylindrical portion 59 a of the vacuum envelope holding part 59 are fixed via a seal member 61. As described above, the cathode 13 is fixed at a predetermined position inside the vacuum envelope 11.

  The fixing member 63 has an end 63 a on the side away from the side fixed to the seal member 61. The connection structure 51a is connected to the cylindrical fixing portion 51. The fixing unit 51 supports the vacuum envelope 11 outside the vacuum envelope 11. The end portion 63 a is connected (fixed) by the connection structure 51 a and the welded portion 65. The cathode holder 14a is given a predetermined length that penetrates the vacuum envelope holder 59 of the housing 3.

  The shape of the fixing member 63 is a bellows (bellows) -like cylindrical shape. Thereby, vibration of the rotating vacuum envelope 11 is reduced from being undesirably transmitted to the cathode 13. Further, a larger assembly error between the cathode holder 14a and the cylindrical fixing portion 51 or the fixing portion 51 is absorbed.

  A plurality of permanent magnets 69 are provided at predetermined positions of the vacuum envelope 11 that holds the anode target 15. The plurality of permanent magnets 69 are portions where the outer diameter of the vacuum envelope 11 is smaller than the outer diameter of the vacuum envelope 11 in the portion surrounding the anode target 15 in the vicinity of the ground electrode 9 (hereinafter referred to as a tip portion). 11d. The plurality of permanent magnets 69 receive propulsive force (magnetic force) for rotating the vacuum envelope 11.

  A stator coil 71 is provided at a predetermined position of the housing 3. The stator coil 71 is substantially coaxial (concentric) with the permanent magnet 69. The permanent magnet 69 is provided so as to surround the distal end portion 11 d of the vacuum envelope 11. The stator coil 71 provides magnetic force (propulsive force) to the permanent magnet 69 at an arbitrary timing. The stator coil 71 is formed as an electromagnet so that rotation can be controlled from the outside. Here, the stator coil 71 functions as a rotational drive device.

  In such an X-ray tube apparatus 1, the vacuum envelope 11 is rotated at a predetermined speed by supplying a predetermined current to the stator coil 71, and an anode target provided inside the vacuum envelope 11. (Rotary anode) 15 is rotated at a predetermined speed. In this state, the electrons emitted from the cathode 13 collide with the anode target 15, so that X-rays having a predetermined wavelength are output from the anode target 15. The outputted X-rays are radiated to the outside from the window portion 11 b defined at a predetermined position of the cylindrical portion of the vacuum envelope 11 and the predetermined defined window portion 3 a of the cylindrical portion of the housing 3.

  The coolant 7 is injected into the housing 3 through a coolant inlet (coolant inlet) 5b provided in the vicinity of the bearing portion 11a of the vacuum envelope 11. The coolant 7 is discharged from the coolant outlet 5 c provided in the vicinity of the ground electrode 9. The coolant 7 is circulated between most of the area outside the vacuum envelope 11 and a predetermined area inside the housing 3. For this reason, the magnetic fluid vacuum seal member 53 and the anode target 15 incorporated in the vacuum envelope 11 are cooled.

  The inside of the vacuum envelope 11, that is, the cathode 13 and the anode target 15 are positioned under a predetermined vacuum by a magnetic fluid vacuum seal member 53. The magnetic fluid vacuum seal member is reported in, for example, “Lubrication”, Vol. 30, No. 8, pp 75-78 by Kamiyama.

  When forming the magnetic fluid vacuum seal member, first, a predetermined amount of magnetic fluid is prepared on the outer periphery of a shaft structure in which a shaft made of a magnetic material or a shaft of a nonmagnetic material is covered with a cylinder made of a magnetic material. Here, the magnetic fluid is a colloidal solution in which ferromagnetic particles are dispersed in a liquid. Next, a magnetic circuit and a permanent magnet are brought close to the shaft or shaft structure to form a magnetic circuit. As a result, the magnetic fluid can remain around the shaft or the shaft structure. The magnetic fluid vacuum seal member is a seal material that maintains a pressure (atmospheric pressure) difference. Providing the magnetic fluid vacuum seal member is beneficial for maintaining the inside of the vacuum envelope 11 rotated at a high speed under a predetermined vacuum (reduced pressure).

  The coolant 7 supplied into the housing 3 is cooled by a heat exchanger 7b provided in a cooler, that is, a cooler unit 7a. The pump 7 c circulates the coolant 7 through the heat exchanger 7 b and between the coolant inlet 5 b and the coolant outlet 5 c, that is, in the circulation path 8 formed in the housing 3. Thereby, the heat generated in the X-ray tube apparatus 1 is released to the outside of the housing 3 through the coolant 7.

  As described above, the coolant 7 can efficiently cool the magnetic fluid vacuum seal member 53 and the anode target 15. In addition, the flow path of the coolant 7 is devised so as to flow in contact with a fixed portion 51 that is generally formed of metal.

  Further, a wettability reducing flange 11 e is provided at a predetermined position of the vacuum envelope 11. The wettability reducing flange 11 e is provided in the vicinity of the anode target 15 of the vacuum envelope 11 in the vicinity of the one end portion 51 b of the fixed portion 51 of the housing 3. The wettability reducing flange 11e is provided integrally with the end portion 11c. The wettability reducing flange 11e can reduce the coolant 7 from entering the bearing member 55 and the magnetic fluid vacuum seal member 53. The wettability reducing flange 11e and the one end 51b of the fixing portion 51 provide a slight gap therebetween, that is, a gap 5d having low wettability. For this reason, the wettability reducing flange 11 e and the one end 51 b can prevent the coolant 7 from entering the inside of the vacuum envelope 11. This prevents the coolant 7 from entering the magnetic fluid vacuum seal member 53 and undesirably lowering the performance (capability) of the magnetic fluid vacuum seal member 53.

  In addition, when using the cooling liquid 7 as a liquid with a comparatively large contact angle as a cooling medium, the clearance gap 5d with low wettability is prescribed | regulated smaller than a fixed magnitude | size. As a result, the coolant 7 is prevented from entering the gap (5d). However, in this embodiment, a medium mixed with water or glycol is used as the cooling medium. In this case, in order to increase the contact angle, it is preferable to coat the flange 11 e of the vacuum envelope 11 and the one end 51 b of the fixing portion 51 with resin or the like. This prevents the coolant 7 from entering the magnetic fluid vacuum seal member 53 and undesirably lowering the performance (capability) of the magnetic fluid vacuum seal member 53.

  Further, the bearing member on the side away from the magnetic fluid vacuum seal member 53 in the bearing member 55 is a seal type. As a result, the coolant 7 can be further prevented from entering the magnetic fluid vacuum seal member 53.

  Although not described in detail, in the rotary anode X-ray tube apparatus shown in FIG. 1, the cooler unit 7a is connected to the housing 3 via a detachable pipe joint.

  Here, the support member 14 and the high-voltage connector 30 connected to the support member 14 will be described.

  In addition to the cathode holder 14a, the support member 14 includes a high voltage wiring portion 14b, a high voltage supply terminal 14c, a plate portion 14d, an end surface 14e, and a side surface 14f. The cathode holder 14a and the plate portion 14d are integrated, and are integrally formed here.

  The high voltage wiring portion 14 b is electrically connected to the cathode 13. The high voltage wiring part 14b is located inside the cathode holder 14a. The high voltage supply terminal 14 c is electrically connected to the high voltage wiring portion 14 b and exposed outside the housing 3. The plate portion 14d closes the opening of the housing 3 on the side opposite to the side where the ground electrode 9 is provided. The plate portion 14d and the cathode holder 14a are formed by ceramics and are joined to each other. The high voltage supply terminal 14c passes through the plate portion 14d.

  The end surface 14e of the plate portion 14d is exposed to the outside of the housing 3 together with the high voltage supply terminal 14c. Here, the end face 14e is a flat surface. A side surface 14 f of the cathode holder 14 a is located in the housing 3, surrounds the high voltage wiring portion 14 b, and is provided with a heat transfer promotion portion 16 that contacts the coolant 7. More specifically, the side surface 14 f is the entire side surface located on the plate portion 14 d side from the portion facing the fixing member 63.

  As shown in FIGS. 1 and 2, in this embodiment, the heat transfer promoting portion 16 is a plurality of protruding portions 16a that are joined to the side surface 14f and protrude outward from the side surface 14f. Here, the protruding portion 16a extends in a direction orthogonal to the extending direction of the high voltage wiring portion 14b. The protrusions 16a are arranged with a gap between each other in the direction along the extending direction of the high voltage wiring portion 14b. The protrusion 16a is made of metal.

  In this embodiment, the protrusion 16a is brazed to the side surface 14f. Therefore, the protruding portion 16a is joined to the side surface 14f via the metallized layer 17a covering the side surface 14f and the brazing material 17b covering the metalized layer 17a.

  The high voltage connector 30 is for applying a high voltage to the cathode 13. The high voltage connector 30 includes a lid portion 31, an epoxy resin 32 filled in the lid portion 31, a silicone plate 33 as an electrical insulating material located between the epoxy resin 32 and the end surface 14 e, and a high voltage cable 34. is doing. The silicone plate 33 has an opening.

  The high voltage cable 34 is covered with the epoxy resin 32 and faces the high voltage supply terminal 14c. The lid 31 is attached to the housing 3 by bolts 35. The high voltage supply terminal 14 c is connected to the high voltage cable 34 through the opening of the silicone plate 33. The silicone plate 33 is in close contact with the end face 14e.

  Next, the vacuum envelope holding part 59 will be described.

  The vacuum envelope holding part 59 has a first flow path t1, a second flow path t2, and a third flow path t3 as flow paths through which the coolant 7 flows. The first flow path t1 is located in the vicinity of the housing 3, and is for flowing the coolant 7 from the coolant inlet 5b side to the coolant outlet 5c side. The first flow path t <b> 1 is formed through a part of the vacuum envelope holding part 59 and forms a circulation path 8.

  The second flow path t2 is located in the vicinity of the cathode holder 14a, and is used for flowing the coolant 7 from the coolant inlet 5b side to the region surrounded by the side surface 14f of the cathode holder 14a and the fixing member 63. . The second flow path t <b> 2 is formed through a part of the vacuum envelope holding part 59, and forms the circulation path 8.

  The third flow path t3 is for allowing the coolant 7 to flow from the region surrounded by the cathode holder 14a and the fixing member 63 to the first flow path t1. The third flow path t <b> 3 is formed through a part of the vacuum envelope holding part 59, and forms the circulation path 8. A region surrounded by the side surface 14 f and the fixing member 63 also forms the circulation path 8.

  According to the rotary anode type X-ray tube apparatus configured as described above, the side surface 14f of the cathode holder 14a is immersed in and in contact with the coolant filled in the housing 3. By cooling the cathode holder 14a, deformation of the high voltage connector 30 can be suppressed, and discharge along the adhesion interface between the high voltage connector and the end face 14e can be suppressed. Furthermore, according to the rotary anode type X-ray tube apparatus of this embodiment, since the plurality of protrusions 16a which are the heat transfer promoting parts 16 are provided on the side surface 14f of the cathode holder 14a, the protrusions 16a are provided. The surface area in contact with the coolant 7 increases as compared with the case where there is no. That is, the cathode holder 14a can be further cooled, the deformation of the high voltage connector 30 can be further suppressed, and the discharge along the adhesion interface between the high voltage connector 30 and the end face 14e can be further suppressed.

  In this embodiment, the example in which the projecting portion 16a extends in a direction orthogonal to the direction in which the high voltage wiring portion 14b extends has been described. However, the present invention is not limited to this example. It may be extended or may be extended in a plurality of different directions. The protruding portion 16a extends in a direction orthogonal to the extending direction of the high voltage wiring portion 14b and extends along the extending direction of the high voltage wiring portion 14b. The cathode holding body 14a The center axis may be shifted by a predetermined angle. Even if the protruding portion 16a is formed in this way, since the total surface area of the side surface 14f and the protruding portion 16a is larger than the surface area of the side surface 14f in contact with the coolant 7, deformation of the high voltage connector 30 can be suppressed, Discharge along the adhesion interface between the high voltage connector 30 and the end face 14e can be suppressed.

  In addition, heat release characteristics can be improved by using an aqueous cooling medium, and stable characteristics can be ensured over a long period of time. Thereby, the lifetime of, for example, an X-ray image diagnostic apparatus or a nondestructive inspection apparatus in which the rotary anode X-ray tube apparatus is incorporated is increased.

  Since the water-based coolant 7 has the highest heat transfer coefficient, the heat transferred to the high-voltage insulating member can be most effectively removed. Of course, for the same reason, the heat of the anode target 15 provided integrally with the vacuum envelope 11 can be removed most promptly by using the aqueous coolant 7.

  Moreover, according to this invention, it is not necessary to consider the insulation with respect to the high voltage of a cooling liquid, a cooling medium with high cooling efficiency can be utilized, and cooling efficiency is improved. Furthermore, according to the present invention, since the life of the rotary anode X-ray tube apparatus itself is increased, the running cost of the X-ray image diagnostic apparatus and the nondestructive inspection apparatus is also reduced.

  Since the end surface 14e of the cathode support 14a is a flat surface, the rotary anode X-ray tube device can be formed in a compact manner. Not limited to this example, the end surface 14e may be a convex surface that protrudes from the inside of the housing 3 to the outside, or a concave surface that is recessed from the inside of the housing 3 to the inside. Compared with the case where the end face 14e is flat, the rotary anode X-ray tube apparatus is bulky, but good adhesion between the electrical insulating rubber 36 and the end face 14e can be realized.

  As described above, it is possible to improve the heat release characteristics and to obtain a rotary anode type X-ray tube device that is highly reliable over a long period of time. Furthermore, it is possible to obtain a rotary anode type X-ray tube apparatus that can ensure insulation of the high-voltage connector over a long period of time.

  Next, a rotary anode type X-ray tube apparatus according to a second embodiment of the present invention will be described in detail. In this embodiment, other configurations are the same as those of the first embodiment described above, and the same parts are denoted by the same reference numerals and detailed description thereof is omitted.

  As shown in FIGS. 3 and 4, the heat transfer promoting portion 16 is a bowl-shaped enclosure 16b joined to the side surface 14f of the cathode support member 14a. Each enclosure 16b has a V-shaped cross section, extends along the extending direction of the high voltage wiring portion 14b, protrudes outward from the side surface 14f, and surrounds the side surface 14f around the high voltage wiring portion 14b. Are formed with a plurality of protrusions arranged adjacent to each other. The enclosure 16b is made of metal.

  According to the rotary anode type X-ray tube apparatus configured as described above, the side surface 14f of the cathode holder 14a is immersed in and in contact with the coolant filled in the housing 3. By cooling the cathode holder 14a, the deformation of the high voltage connector 30 can be suppressed, and the discharge along the adhesion interface between the high voltage connector 30 and the end face 14e can be suppressed. Furthermore, according to the rotary anode X-ray tube apparatus of the second embodiment, the envelope body 16b is provided because the envelope body 16b, which is the heat transfer promoting portion 16, is provided on the side surface 14f of the cathode holder 14a. The surface area in contact with the coolant 7 increases as compared with the case where there is no. That is, the cathode holder 14a can be further cooled, the deformation of the high voltage connector 30 can be further suppressed, and the discharge along the adhesion interface between the high voltage connector 30 and the end face 14e can be further suppressed.

  In the second embodiment, the shape of the surrounding body 16b which is the heat transfer promoting portion 16 is not limited to the above-described example, and can be variously modified. Even if the shape of the surrounding body 16b is changed, the total surface area of the side surface 14f and the surrounding body 16b is larger than the surface area of the side surface 14f in contact with the coolant 7, so that the deformation of the high voltage connector 30 can be suppressed. The discharge along the contact interface between the connector 30 and the end face 14e can be suppressed.

  In addition, heat release characteristics can be improved by using an aqueous cooling medium, and stable characteristics can be ensured over a long period of time. Thereby, the lifetime of, for example, an X-ray image diagnostic apparatus or a nondestructive inspection apparatus in which the rotary anode X-ray tube apparatus is incorporated is increased.

  Since the water-based coolant 7 has the highest heat transfer coefficient, the heat transferred to the high-voltage insulating member can be most effectively removed. Of course, for the same reason, the heat of the anode target 15 provided integrally with the vacuum envelope 11 can be removed most promptly by using the aqueous coolant 7.

  Moreover, according to this invention, it is not necessary to consider the insulation with respect to the high voltage of a cooling liquid, a cooling medium with high cooling efficiency can be utilized, and cooling efficiency is improved. Furthermore, according to the present invention, since the life of the rotary anode X-ray tube apparatus itself is increased, the running cost of the X-ray image diagnostic apparatus and the nondestructive inspection apparatus is also reduced.

  Since the end surface 14e of the cathode support 14a is a flat surface, the rotary anode X-ray tube device can be formed in a compact manner. Not limited to this example, the end surface 14e may be a convex surface that protrudes from the inside of the housing 3 to the outside, or a concave surface that is recessed from the inside of the housing 3 to the inside. Compared with the case where the end face 14e is flat, the rotary anode X-ray tube apparatus is bulky, but good adhesion between the electrical insulating rubber 36 and the end face 14e can be realized.

  As described above, it is possible to improve the heat release characteristics and to obtain a rotary anode type X-ray tube device that is highly reliable over a long period of time. Furthermore, it is possible to obtain a rotary anode type X-ray tube apparatus that can ensure insulation of the high-voltage connector over a long period of time.

  Next, a rotary anode X-ray tube apparatus according to a third embodiment of the present invention will be described in detail. In this embodiment, other configurations are the same as those of the first embodiment described above, and the same parts are denoted by the same reference numerals and detailed description thereof is omitted.

  As shown in FIG. 5, the heat transfer promoting portion 16 is a concavo-convex pattern 16c formed on the side surface 14f of the cathode support member 14a. Here, the concavo-convex pattern 16c is formed by a plurality of concave portions formed inwardly from the side surface 14f.

  According to the rotary anode type X-ray tube apparatus configured as described above, the side surface 14f of the cathode holder 14a is immersed in and in contact with the coolant 7 filled in the housing 3. By cooling the cathode holder 14a, the deformation of the high voltage connector 30 can be suppressed, and the discharge along the adhesion interface between the high voltage connector 30 and the end face 14e can be suppressed. Furthermore, according to the rotating anode X-ray tube apparatus of the third embodiment, the uneven pattern 16c that is the heat transfer promoting portion 16 is formed on the side surface 14f of the cathode holder 14a, so that the uneven pattern is formed. The surface area in contact with the coolant 7 is increased as compared with the case where it is not. That is, the cathode holder 14a can be further cooled, the deformation of the high voltage connector 30 can be further suppressed, and the discharge along the adhesion interface between the high voltage connector and the end face 14e can be further suppressed.

  In 3rd Embodiment, although the uneven | corrugated pattern 16c which is the heat transfer acceleration | stimulation part 16 demonstrated the example formed by several recessed part formed inwardly from the side surface 14f, it is not restricted to this example, An uneven | corrugated pattern 16c may be formed by a plurality of convex portions formed outward from the side surface 14f, or may be formed by a plurality of concave portions and a plurality of convex portions. The shape of the concavo-convex pattern 16c is not limited to the above example, and can be variously modified. For example, the cross-sectional shape of the concave portion or the convex portion is not limited to the U shape, and may be a V shape or the like. Even when the uneven pattern 16c is formed in this way, the surface area of the side surface 14f on which the uneven pattern 16 is formed is larger than the surface area of the side surface 14f on which the uneven pattern 16c that contacts the coolant 7 is not formed. The deformation of the connector 30 can be suppressed, and the discharge along the adhesion interface between the high voltage connector 30 and the end face 14e can be suppressed.

  In addition, heat release characteristics can be improved by using an aqueous cooling medium, and stable characteristics can be ensured over a long period of time. Thereby, the lifetime of, for example, an X-ray image diagnostic apparatus or a nondestructive inspection apparatus in which the rotary anode X-ray tube apparatus is incorporated is increased.

  Since the water-based coolant 7 has the highest heat transfer coefficient, the heat transferred to the high-voltage insulating member can be most effectively removed. Of course, for the same reason, the heat of the anode target 15 provided integrally with the vacuum envelope 11 can be removed most promptly by using the aqueous coolant 7.

  Moreover, according to this invention, it is not necessary to consider the insulation with respect to the high voltage of a cooling liquid, a cooling medium with high cooling efficiency can be utilized, and cooling efficiency is improved. Furthermore, according to the present invention, since the life of the rotary anode X-ray tube apparatus itself is increased, the running cost of the X-ray image diagnostic apparatus and the nondestructive inspection apparatus is also reduced.

  Since the end surface 14e of the cathode support 14a is a flat surface, the rotary anode X-ray tube device can be formed in a compact manner. Not limited to this example, the end surface 14e may be a convex surface that protrudes from the inside of the housing 3 to the outside, or a concave surface that is recessed from the inside of the housing 3 to the inside. Compared with the case where the end face 14e is flat, the rotary anode X-ray tube apparatus is bulky, but good adhesion between the electrical insulating rubber 36 and the end face 14e can be realized.

  As described above, it is possible to improve the heat release characteristics and to obtain a rotary anode type X-ray tube device that is highly reliable over a long period of time. Furthermore, it is possible to obtain a rotary anode type X-ray tube apparatus that can ensure insulation of the high-voltage connector over a long period of time.

  In addition, this invention is not limited to the said embodiment itself, In the stage of implementation, it can change and implement a component within the range which does not deviate from the summary. Further, various inventions can be formed by appropriately combining a plurality of constituent elements disclosed in the embodiment. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, you may combine suitably the component covering different embodiment.

  For example, the heat transfer promotion portion 16 provided on the side surface 14f, such as the protruding portion 16a and the enclosure 16b, is not limited to metal, and is formed of a material having a higher heat transfer rate than the member forming the side surface 14f of the support member 14. If it is, the effect mentioned above can be acquired. However, when the heat transfer promoting portion 16 is provided on the side surface 14f, the surface area becomes large. In some cases, the heat transfer promoting portion 16 has a heat transfer coefficient equal to or lower than that of the member forming the side surface 14f of the support member 14. The effects described above can be obtained even if the material is formed.

  The cooling medium 7 is not limited to an aqueous system, and insulating oil or a gas body such as air can be used. As the bearing member, a sliding bearing or a magnetic bearing can be used in addition to a rolling bearing such as a ball bearing or a roll bearing. The fixing portion 51 is directly fixed to the housing via an electric insulating member. However, the elastic member, the damping member, or the absorbing member may be disposed between the electric insulating member and the housing, or between the electric insulating member and the fixed portion 51. Thereby, it is also possible to further reduce the vibration of the X-ray tube apparatus accompanying the rotation of the rotating part. The electrical insulating material of the high voltage connector 30 may be in close contact with the end surface 14e of the support member 14 directly or indirectly.

  The present invention is not limited to the rotary anode X-ray tube apparatus used in the X-ray CT apparatus and the X-ray diagnostic apparatus, but can be applied to all rotary anode X-ray tube apparatuses.

FIG. 1 is a schematic exploded sectional view showing a rotary anode type X-ray tube apparatus according to a first embodiment of the present invention. FIG. 2 is an enlarged cross-sectional view of the rotary anode X-ray tube device taken along line AA in FIG. 1, and particularly shows a cathode support and a protrusion. FIG. 3 is a schematic exploded sectional view showing a rotary anode type X-ray tube apparatus according to a second embodiment of the present invention. 4 is an enlarged cross-sectional view of the rotary anode type X-ray tube device taken along line BB in FIG. 3, and particularly shows a cathode support and a protrusion. FIG. 5 is a schematic exploded sectional view showing a rotary anode type X-ray tube apparatus according to a third embodiment of the present invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... X-ray tube apparatus, 3 ... Housing, 5 ... X-ray tube main body, 3a ... Window part (of X-ray tube main body) 5b ... Coolant inlet (of X-ray tube main body), 5c ... (X-ray tube main body) ) Coolant outlet, 5d (low X-ray tube body) gap, low wettability, 7 ... Coolant (aqueous coolant), 7a ... Cooler (cooler unit), 7b ... Heat exchanger, 7c ... Pump, 8 ... circulation path, 11 ... vacuum envelope, 11b ... window portion (vacuum envelope), 11c ... end portion (vacuum envelope), 11d ... tip portion (vacuum envelope), 11e ... Wetability reducing flange (of vacuum envelope), 13 ... cathode, 14 ... support member, 14a ... cathode holding body, 14b ... high voltage wiring part, 14c ... high voltage supply terminal, 14d ... plate part, 14e ... end face, 14f ... side face, 15 ... anode target, 16 ... heat transfer promoting part, 16a ... projecting part, 16b ... enclosure, 16c ... unevenness Turn, 17a ... Metallized layer, 17b ... Brazing material, 30 ... High voltage connector, 31 ... Lid, 32 ... Epoxy resin, 33 ... Silicone plate, 34 ... High voltage cable, 51 ... (Cylindrical) fixing part, 51a ... Connected structure (of cylindrical fixing part), 53 ... Magnetic fluid vacuum seal member, 55 ... Rolling bearing (bearing), 57 ... Support member, 59 ... Vacuum envelope holding part, 59a ... (Vacuum envelope holding) Cylindrical part, 61 ... sealing member, 63 ... fixing member, 65 ... welded part, 69 ... permanent magnet, 71 ... stator coil.

Claims (18)

A vacuum envelope integrated with the anode target and formed to be rotatable;
A housing that houses at least the vacuum envelope and rotatably holds the vacuum envelope;
A circulation path formed in the housing and in which a cooling medium circulates in the vicinity of at least the anode target;
A stationary cathode housed in the vacuum envelope and stationary;
A support member for supporting the cathode;
A bearing mechanism and a vacuum seal mechanism provided between the vacuum envelope and the housing or a fixed body fixed to the housing;
A rotation driving device for rotating the vacuum envelope,
The support member is
A high-voltage wiring portion electrically connected to the cathode;
A high voltage supply terminal electrically connected to the high voltage wiring portion and exposed outside the housing;
A side surface located in the housing, surrounding the high voltage wiring portion, and provided with a heat transfer promoting portion in contact with the cooling medium;
A rotating anode type X-ray tube apparatus characterized by comprising:   2. The rotary anode X-ray tube device according to claim 1, wherein the heat transfer promotion part is a plurality of protrusions that are joined to a side surface of the support member and protrude outward from the side surface.   The rotary anode X-ray tube apparatus according to claim 1, wherein the heat transfer promoting portion is a bowl-shaped enclosure joined to a side surface of the support member.   The rotary anode X-ray tube apparatus according to claim 2 or 3, wherein the heat transfer promoting part has a higher heat transfer rate than a member forming a side surface of the support member.   The rotary anode type X-ray tube device according to claim 2 or 3, wherein the heat transfer promoting portion is made of metal.   The rotary anode X-ray tube apparatus according to claim 1, wherein the heat transfer promoting portion is a concave / convex pattern formed on a side surface of the support member. A high voltage connector for applying a high voltage to the cathode;
The support member further includes an end surface exposed to the outside of the housing together with the high voltage supply terminal,
The high voltage connector is electrically connected to the high voltage supply terminal;
The rotary anode X-ray tube according to any one of claims 1 to 6, wherein an electrical insulating material of the high-voltage connector is directly or indirectly adhered to an end face of the support member. apparatus.   The rotary anode type X-ray tube device according to claim 7, wherein an end surface of the support member is a flat surface.   The rotary anode type X-ray tube device according to claim 7, wherein an end surface of the support member is a convex surface convex from the inside of the housing toward the outside.   The rotary anode X-ray tube apparatus according to claim 7, wherein an end surface of the support member is a concave surface that is recessed from the inside of the housing toward the inside.   The rotary anode X-ray tube apparatus according to claim 1, wherein the housing has a cooling medium inlet formed at a position connected to the circulation path and facing a side surface of the support member.   12. The liquid crystal display device according to claim 1, wherein the vacuum seal mechanism includes a magnetic fluid vacuum seal member. A heat exchanger for cooling the cooling medium;
The liquid crystal according to any one of claims 1 to 12, further comprising a circulation pump that circulates the cooling medium between the heat exchanger and between the housing and the vacuum envelope. Display device.   The cooling medium is in contact with an inert gas between the housing and the vacuum envelope, and the inert gas is dissolved in a saturated state in advance. 14. The rotary anode X-ray tube device according to any one of items 13 to 13.   The rotary anode X-ray tube apparatus according to any one of claims 1 to 14, wherein the cooling medium is an aqueous cooling medium whose main component is water.   The rotary anode X-ray tube device according to claim 15, wherein the conductivity of the water-based cooling medium is 1 mS / m or less. An anode target that generates X-rays when electrons collide;
An electron emission source for emitting electrons toward the anode target;
A vacuum envelope for holding the anode target and the electron emission source under a predetermined reduced pressure;
A housing containing the vacuum envelope and hermetically sealed so that a coolant can circulate between the vacuum envelope;
A support member for fixing the electron emission source to the housing;
A holding member for rotatably holding the vacuum envelope in the housing;
A vacuum seal member that is positioned between the vacuum envelope and the holding member and that allows the vacuum envelope to rotate within the housing while maintaining the pressure within the vacuum envelope;
The support member is
A high-voltage wiring portion electrically connected to the electron emission power source;
A high voltage supply terminal electrically connected to the high voltage wiring portion and exposed outside the housing;
A side surface located in the housing, surrounding the high voltage wiring portion, and provided with a heat transfer promoting portion in contact with the cooling medium;
A rotary anode type X-ray tube device characterized by comprising: A vacuum envelope integrated with the anode target and formed to be rotatable;
A housing that houses at least the vacuum envelope and rotatably holds the vacuum envelope;
A circulation path formed in the housing and in which a cooling medium circulates in the vicinity of at least the anode target;
A stationary cathode housed in the vacuum envelope and stationary;
A support member for supporting the cathode;
A bearing mechanism and a vacuum seal mechanism provided between the vacuum envelope and the housing or a fixed body fixed to the housing;
A rotation driving device for rotating the vacuum envelope;
A high voltage connector for applying a high voltage to the cathode,
The support member is
A high-voltage wiring portion electrically connected to the cathode;
A high voltage supply terminal electrically connected to the high voltage wiring portion and exposed outside the housing;
Along with the high voltage supply terminal, an end surface exposed to the outside of the housing;
A side surface located in the housing, surrounding the high-voltage wiring portion, and provided with a heat transfer promoting portion in contact with the cooling medium,
The high voltage connector is electrically connected to the high voltage supply terminal;
The rotary anode type X-ray tube device, wherein the electrical insulating material of the high-voltage connector is in direct or indirect contact with the end face of the support member.

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