JP5477958B2 - X-ray tube container - Google Patents

Description

  The present invention relates to an X-ray tube container for storing an X-ray tube in an X-ray irradiation unit provided in an X-ray imaging apparatus for dental use, otolaryngology and the like.

  An X-ray imaging apparatus includes an X-ray irradiation unit that irradiates a patient with X-rays, an X-ray detection unit that detects X-rays transmitted through the patient, and a swivel arm that faces the X-ray irradiation unit and the X-ray detection unit. (See, for example, Patent Document 1). The X-ray irradiation unit includes an X-ray tube, and the thermal electrons emitted from the cathode (filament) of the X-ray tube collide with the anode (target) to irradiate X-rays. The X-ray tube is housed in an X-ray tube container, and the X-ray tube container contains insulating oil for insulating a high voltage applied to the X-ray tube and for cooling the X-ray tube that generates heat during operation. Vacuum impregnation. Insulating oil expands when the X-ray tube generates heat and contracts when the X-ray tube cools. In a dental X-ray imaging apparatus, an X-ray tube container is formed by joining a plurality of thin metal plates by soldering. Since the thin metal plate can be deformed according to the expansion and contraction of the contained insulating oil, the X-ray tube container thereby absorbs the volume change of the insulating oil.

  As mentioned above, the X-ray tube container has a plurality of thin metal plates joined by soldering. Therefore, when maintaining the X-ray tube, it is necessary to remove the soldering and open the metal plate. It took time and effort, and required high skill of skilled workers.

JP 2009-172112 A

  Therefore, the problem to be solved by the present invention is that the leakage of insulating oil can be surely prevented, and when maintaining an X-ray tube or the like, it can be opened and closed very easily, and extra labor and skill are unnecessary. It is to provide a wire tube container.

In order to solve the above problems, an X-ray tube container according to the present invention is:
In an X-ray tube container that houses an X-ray tube and a power supply unit and is vacuum-impregnated with insulating oil inside,
A container body that has an opening and can be deformed by expansion and contraction of the insulating oil, a lid that closes the opening and does not deform even by expansion and contraction of the insulating oil, and is provided on the container body along the periphery of the opening A flange portion that extends outward, a connecting member that connects the flange portion and the lid, and a seal member that seals a joint between the flange and the lid.

  Preferably, the container body and the flange portion are integrally formed by pressing a thin plate member, and the flange portion is provided with a reinforcing member.

  Preferably, the lid includes a groove portion that accommodates the seal member, and the seal member is formed of an oil-resistant and heat-resistant rubber O-ring, the length of which is longer than the groove portion, and is in close contact with the outer wall of the groove portion.

  Preferably, the container main body and the lid body have a rectangular shape, and the groove portion has a rectangular shape in which the four corner portions are formed by small arcs and the sides between the four corner portions are formed by large arcs.

  Preferably, the groove is based on the dimensions of the O-ring internal pressure JIS standard, and the width of the groove is smaller than the JIS standard and larger than the thickness of the O-ring.

  Preferably, the depth dimension of the groove is smaller than the dimension of JIS standard, and the crushing rate of the O-ring is 30% or less.

  Preferably, an X-ray radiation window fitting attached via a fixture is provided, and the fixture is screwed into the X-ray radiation window fitting so as to tighten the X-ray radiation window fitting and the container body or the lid. The sealing member is provided between the fixture and the container body or the lid.

  Preferably, the X-ray radiation window fitting is attached to the container main body and has a protrusion that prevents deformation due to expansion and contraction of the insulating oil.

  As described above, the X-ray tube container according to the present invention includes a combination of a container body that is deformed by expansion and contraction of insulating oil and a lid that is not deformed by expansion and contraction of insulating oil. Furthermore, the X-ray tube container includes a flange portion along the opening of the container main body, a connecting member that connects the flange portion and the lid, and a seal member that seals a joint between the flange and the lid. Thereby, the lid can be easily opened and closed by removing the connecting member when maintaining the X-ray tube. Furthermore, the volume change of the insulating oil is allowed and absorbed by the deformation of the container body so that the lid body does not deform. And since the lid of the container body is connected to the flange portion through the seal member, the sealing property between the container body and the lid is maintained even if the volume of the insulating oil changes, and the leakage of the insulating oil is ensured. Can be prevented.

The side view which shows X-ray imaging apparatus. The perspective view which shows an X-ray tube container. An X-ray tube container is shown, (a) is a top view, (b) is the bb sectional view taken on the line of (a). It is a figure explaining an X-ray tube container, Comprising: (a) is a top view which shows the back surface side of a cover body, (b) is an expanded sectional view which shows the junction part of a container main body and a cover body. Sectional drawing for demonstrating the crushing rate of an O-ring. It is a figure explaining an X-ray emission window metal fitting, Comprising: (a) is sectional drawing which shows the state which attached the X-ray emission window metal fitting to the container main body, (b) is before attaching an X-ray emission window metal fitting to a container main body. Sectional drawing which shows a state. The state which attached the X-ray radiation window metal fitting to the lid is shown, (a) is a top view and (b) is a bb line sectional view of (a). 1 is a front view showing a standing type X-ray CT imaging apparatus.

  Hereinafter, an X-ray imaging apparatus according to the present invention will be described with reference to the drawings.

  As shown in FIG. 1, the X-ray imaging apparatus includes a base 56 installed on a floor surface, and a column 50 is erected on the base 56. The X-ray imaging apparatus includes an X-ray irradiation unit 54 supported by an arm 53, and the arm 53 is supported by the column 50 so as to be movable up and down so that the height of the X-ray irradiation unit 54 can be adjusted. In addition, the X-ray imaging apparatus includes a chair 51 on a base 56 and a backrest 52 on a support column 50. At the time of X-ray imaging, the subject sits on the chair 51 and leans against the backrest 52. Then, the subject sets an X-ray receiver (not shown) such as a small flat sensor or a film at a position to be imaged in the mouth (around the teeth), and the controller 55 controls the tube voltage, tube current, etc. Control is performed and X-rays are irradiated from the X-ray irradiator 54 toward the X-ray receiver for imaging. The X-ray irradiator 54 contains an X-ray tube container 1 that houses an X-ray tube and the like.

  As shown in FIGS. 2 and 3, the X-ray tube container 1 includes a container body 2 and a lid 3. As shown in FIG. 3A, the X-ray tube container 1 houses an X-ray tube 10 that generates X-rays. The X-ray tube container 1 is vacuum-impregnated with an insulating oil 11 for insulating the high voltage applied to the X-ray tube 10 and for cooling the X-ray tube 10 that generates heat during operation. The X-ray tube container 1 is configured in a rectangular shape as a whole in consideration of the storage properties of the X-ray tube 10 and the like. As shown in FIG. 2, the X-ray tube container 1 irradiates X-rays generated in the X-ray tube 10 through an X-ray emission window fitting 7. As shown in FIG. 3A, the X-ray tube container 1 houses a high-voltage power supply unit 12 connected to the X-ray tube 10. As shown in FIG. 3B, the container body 2 has an opening 2a. The container body 2 includes a flange portion 20 extending outward along the periphery of the opening 2a. The lid 3 closes the opening 2 a of the container body 2.

  As shown in FIG. 3B, the lid 3 is installed and joined to the flange portion 20 of the container body 2. The lid 3 includes a screw hole 31 and a groove 30 in the joint 3a. The screw hole 31 is provided on the outer side, and the groove portion 30 is provided on the inner side. The groove part 30 accommodates the container seal member 4 for sealing the container body 2 and the lid 3. The lid 3 is installed on the flange portion 20 of the container body 2 and is connected by the connecting member 6 at the joint 3a. The flange portion 20 is provided with a reinforcing member 5 for reinforcing the opposite side of the lid 3. The reinforcing member 5 is provided with a metal plate member over the entire circumference of the flange portion 20. The connecting member 6 includes a plurality of screw members, and is provided in the screw hole 31 provided in the lid body 3, the screw hole 20 a provided in the flange portion 20 (FIG. 4B), and the reinforcing member 5. The container body 2, the lid body 3 and the reinforcing member 5 are connected to each other by being screwed into the screw hole 5 a (FIG. 4B).

  The container body 2 is integrally formed with the flange portion 20 by pressing a metal thin plate member (for example, 0.3 mm to 0.8 mm). The lid 3 is made of a thick metal plate member (for example, 5 mm to 10 mm). As described above, the X-ray tube container 1 contains the insulating oil 11, and the volume of the insulating oil 11 expands and contracts in accordance with the heat generation and cooling of the X-ray tube 10. Since the container main body 2 is made of a thin metal plate member, the container main body 2 is deformed according to the volume change of the insulating oil 11 and absorbs the volume change of the insulating oil 11. The lid 3 has a rigidity that does not deform even if the volume of the insulating oil 11 changes.

  As shown in FIG. 4, the lid 3 is configured in a rectangular shape. The groove part 30 is configured in a rectangular shape along the inner periphery of the lid 3. The groove portion 30 is formed in a rounded shape so that the four corner portions 300 can take corners, and has a long side 301 and a short side 302 between these 300 portions. The groove part 30 has an outer wall 30a on the outer side and an inner wall 30b on the inner side. The container seal member 4 is made of an oil-resistant and heat-resistant rubber O-ring in consideration of productivity and economy.

  When the O-ring 4 is housed in the groove 30 and attached, the O-ring 4 is easier to attach if it is slightly shorter than the groove 30. Then, the O-ring 4 comes into close contact with the inner wall 30 b at the four corners 300 of the groove 30. However, in that case, when the insulating oil 11 expands due to the heat generated by the X-ray tube 10, the internal pressure of the X-ray tube container 1 increases, and the O-ring 4 at the four corners 300 rises, thereby reducing the sealing performance. Therefore, the O-ring 4 is slightly longer than the entire length of the groove portion 30 so that the O-ring 4 is in close contact with the outer wall 30 a over the entire circumference of the groove portion 30 when mounted. Thereby, even if the internal pressure of the X-ray tube container 1 becomes high, the O-ring 4 does not float around the entire circumference including the four corner portions 300, and the sealing performance can be maintained. Further, even when the X-ray tube 10 is cooled and the insulating oil 11 is contracted and the external pressure of the X-ray tube container 1 is increased, the O-ring 4 can maintain the sealing performance without being lifted.

  Furthermore, if the O-ring 4 is slightly longer than the groove portion 30, the ease of attachment such as being easily detached during assembly is deteriorated. However, in order to solve this problem, the long side 301 and the short side 302 are rounded with a large diameter. Specifically, for example, in the case of the lid 3 of 200 mm × 140 mm, the radius R1 of the long side 301 is 5000 to 7000 mm, and the radius R2 of the short side 302 is 3000 to 4000 mm.

  The shape and dimensions of the mounting groove 30 with respect to the O-ring 4 are defined by JIS (Japanese Industrial Standard). In the JIS standard, the shape and size of the groove 30 are defined for internal pressure and external pressure. As described above, since both the internal pressure and the external pressure are applied to the X-ray tube container 1, it is necessary to ensure hermeticity even when both the external pressure and the internal pressure act. Even the JIS standard cannot be applied as it is. Considering the fact that the internal pressure is greater than the external pressure in the temperature change of the X-ray tube 10 and the volume change of the insulating oil 11, the groove portion 30 is based on the shape and dimensions of the groove portion of the JIS standard when the internal pressure acts. However, the width dimension W is made about 8 to 12% smaller than the JIS standard so that the movement allowance is reduced even when an external pressure is applied. Further, the width dimension W of the groove 30 is slightly larger than the thickness (wire diameter) of the O-ring 4 so that the O-ring 4 can be accommodated and there is a movement allowance. For example, when the thickness (wire diameter) of the O-ring 4 is 3.1 mm, according to the JIS standard for internal pressure, the width of the groove is 4.1 mm. The width dimension W is set to 3.7 mm. Thus, the width dimension W of the groove part 30 is smaller than the dimension of the JIS standard for internal pressure, larger than the thickness of the O-ring 4, and has a slight movement allowance (allowance) so that it can cope with the external pressure action. ing.

  More preferably, the depth dimension t of the groove part 30 is made about 2 to 6% smaller than the JIS standard to reduce the movement allowance. And the depth dimension t of the groove part 30 is set so that the crushing rate of the O-ring 4 is 30% or less in consideration of fatigue (permanent deformation) of the O-ring 4 and the like as shown in FIG. The crushing rate of the O-ring 4 is calculated by crushing allowance (A + B) / O-ring wire diameter × 100%. For example, when the thickness (wire diameter) of the O-ring 4 is 3.1 mm, according to the internal pressure JIS standard, the width of the groove is 2.4 mm. Here, in order to make the depth dimension t of the groove 30 smaller than JIS standard 2.4 mm and the crushing rate of the O-ring 4 to be 30% or less, for example, t = 2.3 mm, crushing allowance (A + B) = 0.8 mm (= 3.1 mm-2.3 mm), crush rate = 25.8% (= 0.8 / 3.1 × 100).

  As shown in FIG. 6, the X-ray radiation window fitting 7 is attached to the container main body 2 via the fixture 70. The X-ray radiation window fitting 7 has a protruding portion 7a that largely protrudes along the outer periphery on one end side thereof. The container body 2 has an insertion hole 2b through which the X-ray radiation window fitting 7 is inserted. The first fixture 70 attaches the X-ray radiation window fitting 7 to the container body 2. The first fixture 70 is tubular, and an inner peripheral portion 70 b thereof is screwed to the outer peripheral portion 7 c of the X-ray radiation window fitting 7. Moreover, the 1st fixture 70 has the inclination part 70a in the one end side of the inside. Then, the X-ray radiation window fitting 7 is inserted into the insertion hole 2 b from the inside of the container body 2, and the protruding portion 7 a is brought into contact with the container body 2. Thereafter, a first seal member 71 such as an O-ring is fitted on the outer periphery of the X-ray radiation window fitting 7, and the first fixture 70 is screwed and tightened. Thereby, the 1st fixture 70 adheres the container main body 2 and the protrusion part 7a, and fixes the X-ray radiation window metal fitting 7 to the container main body 2. FIG. Further, as shown in FIG. 6A, a triangular storage portion 70 c that stores the first seal member 71 is formed by the inclined portion 70 a. As a result, the gap between the X-ray radiation window fitting 7 and the container body 2 can be sealed to prevent the insulating oil 11 from leaking, and there is no need to prevent leakage by soldering as in the prior art. Excellent.

  The X-ray radiation window fitting 7 has a two-stage inner diameter, and has a small diameter portion 700 on one end side and a large diameter portion 701 on the other end side. As a result, the mounting portion 7e is formed on the outer periphery of the small-diameter portion 700 of the X-ray radiation window metal fitting 7. The mounting portion 7e mounts a circular plate-like window member 73. The window member 73 transmits a predetermined amount of X-rays from the X-ray tube 10 and closes the small diameter portion 700 to prevent the insulating oil 11 from leaking. The placement portion 7e has an annular groove portion 7b for accommodating the second seal member 74 such as an O-ring. In the X-ray radiation window metal fitting 7, the second fixture 72 is fitted into the large-diameter portion 701 inside. The second fixture 72 is tubular, and its outer peripheral portion 72 a is screwed into the inner peripheral portion 7 d of the X-ray radiation window fitting 7. Then, the second seal member 74 is accommodated in the groove portion 7b of the X-ray emission window fitting 7, the window member 73 is placed on the placement portion 7e, and the second attachment portion 72 is screwed and tightened. Thereby, the 2nd fixture 72 closely_contact | adheres the window member 73 and the mounting part 7e, and fixes the window member 73 to the X-ray radiation window metal fitting 7. FIG. Then, the second seal member 74 seals the gap between the window member 73 and the X-ray radiation window fitting 7.

  As described above, the X-ray radiation window fitting 7 has the large protruding part 7a having high rigidity joined to the thin container body 2, so that the protruding part 7a reinforces the container body 2 even when the insulating oil 11 expands and contracts. To avoid deformation. Thereby, the leakage of the insulating oil 11 becomes very small.

  As shown in FIG. 7, the X-ray emission window fitting 7 can be attached to the lid 3 according to the type of the X-ray imaging apparatus. In the same manner as described above, the X-ray radiation window fitting 7 is covered with the first attachment 70, the first seal member 71, the second attachment 72, the window member 73, the second seal member 74, and the like. It is attached to the body 3.

  The X-ray tube container 1 can be applied to various X-ray imaging apparatuses such as a panoramic X-ray imaging apparatus and a cephalo X-ray imaging apparatus. As shown in FIG. 8, the standing type X-ray CT imaging apparatus is configured to be capable of panoramic imaging, CT imaging, and cephalometric imaging. The X-ray CT imaging apparatus includes a base 65 installed on the floor surface and a support column 66 erected in the vertical direction from the base 65. The support frame 67 is supported by the support 66 and moves up and down along the support 66. The support frame 67 supports the rotary drive unit 67a at the upper part and supports the head support unit 67b at the lower part. The support frame 67, the rotation drive unit 67a, and the head support unit 67b are configured in a U shape when viewed from the front. The rotation drive unit 67a supports the turning arm 63 in a rotatable manner. The head support unit 67b includes a head holding unit 64 that holds the head of the subject. The swivel arm 63 includes an X-ray image receiving unit 61 on one side and an X-ray irradiation unit 62 on the other side. The X-ray irradiation unit 62 stores the X-ray tube container 1 and emits X-rays.

DESCRIPTION OF SYMBOLS 1 X-ray tube container 10 X-ray tube 11 Insulating oil 2 Container main body 20 Flange part 2a Opening part 3 Cover body 30 Groove part 30a Outer wall 300 Four corners 301 Long side 302 Short side 4 Container seal member (O-ring)
40 Joint part 5 Reinforcement member 6 Connecting member W Groove width dimension t Groove depth dimension 7 X-ray radiation window fitting 7a Protruding part 70 First fixture 71 First seal member (O-ring)

Claims (8)

In an X-ray tube container that houses an X-ray tube and a power supply unit and is vacuum-impregnated with insulating oil inside,
A container body that has an opening and is deformable by expansion and contraction of the insulating oil; a lid that closes the opening and does not deform by expansion and contraction of the insulating oil; and the opening provided in the container body. A flange portion that extends outward along the periphery of the portion, a connecting member that connects the flange portion and the lid, and a seal member that seals a joint between the flange and the lid. An X-ray tube container characterized by that.   The X-ray tube container according to claim 1, wherein the container body and the flange portion are integrally formed by pressing a thin plate member, and a reinforcing member is provided on the flange portion.   The lid includes a groove portion that accommodates the seal member, and the seal member is formed of an oil-resistant and heat-resistant rubber O-ring, the length of which is longer than the groove portion, and is in close contact with the outer wall of the groove portion. The X-ray tube container according to claim 1 or 2, wherein   The container body and the lid body are formed in a rectangular shape, and the groove portion is formed in a rectangular shape in which four corner portions are formed with small arcs and sides between the four corner portions are formed with large arcs. Item 4. The X-ray tube container according to Item 3.   4. The groove portion is based on a JIS standard dimension for internal pressure of the O-ring, and a width dimension of the groove portion is smaller than a dimension of the JIS standard and larger than a thickness of the O-ring. X-ray tube container described in 1.   6. The X-ray tube container according to claim 5, wherein a depth dimension of the groove is smaller than a dimension of the JIS standard, and a crushing rate of the O-ring is 30% or less.   An X-ray radiation window fitting attached via a fixture is provided, and the fixture is screwed into the X-ray radiation window fitting to fasten the X-ray emission window fitting and the container body or the lid. The X-ray tube container according to claim 1, wherein a seal member is provided between the fixture and the container main body or the lid body.   The X-ray tube container according to claim 7, wherein the X-ray radiation window metal fitting is attached to the container main body and has a protrusion that prevents deformation due to expansion and contraction of the insulating oil.

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