CN103548424B - X-ray generator - Google Patents

Abstract

The invention provides a kind of X-ray generator, it is arranged in bone density measurement system etc., and the top of X-ray generation unit (14) is provided with structure (44).Specifically, structure (44) is arranged at filter element (42) around, and structure (44) is made up of a level board (52) and multiple vertical panel (54).When having scattered x-ray in the generation of the inside of filter element (42), this scattered x-ray is blocked by structure (44).By the thermolysis of structure (44), and X-ray tube is cooled efficiently.Structure (44) also plays electromagnetic shielding action.

Description

X-ray generating device

technical field

The invention relates to an X-ray generating device, in particular to a heat dissipation structure in the X-ray generating device.

Background technique

Bone density measurement devices, X-ray imaging devices, CT imaging devices, and the like are known as devices that measure subjects using X-rays. These devices all include an X-ray generator (see Patent Documents 1 and 2 below). The X-ray generating device includes an X-ray generating unit including an X-ray generating tube and a shield case housing the X-ray generating tube. In the shielding case, insulating oil is packaged together with the X-ray generating tube. Insulating oil plays the role of insulation and heat dissipation. A high voltage is applied to the X-ray generating tube. In an X-ray generating tube, most of the injected electrical energy will be converted into thermal energy.

In a bone density measurement device, X-rays emitted from an X-ray generating unit usually pass through a filter unit and are irradiated to a subject. The X-ray detector detects X-rays that have passed through the subject. In bone density measurement, high voltage and low voltage are alternately applied to the X-ray generating tube. Correspondingly, one or more filters are selectively inserted in the path of the x-ray beam. For example, there are cases where a filter is inserted only when irradiating high-energy X-rays, and dedicated filters are sometimes inserted when irradiating high-energy X-rays and when irradiating low-energy X-rays. In either case, it is necessary to periodically insert and remove one or more filters. Therefore, as a filter unit, a disc-shaped unit or a cylindrical unit is used. In disc-type units, discs incorporating one or more fan-shaped filters are utilized. The disk rotates about an axis of rotation parallel to the X-ray beam. In a cylindrical unit, a cylinder in which one or more curved filters are incorporated is used (see Patent Document 3 below). The cylinder rotates about an axis of rotation orthogonal to the X-ray beam.

prior art literature

patent documents

Patent Document 1: Japanese Patent Laid-Open No. 2007-149521

Patent Document 2: Japanese Patent Laid-Open No. 2007-026800

Patent Document 3: Japanese Patent No. 4499593

Contents of the invention

The problem to be solved by the invention

Since a large amount of heat is generated in such an X-ray generator as described above, it is necessary to sufficiently dissipate heat. However, sufficient heat dissipation has not always been possible in the prior art. In a structure in which a filter unit is mounted on the top plate (plate on the subject side) of the X-ray generating unit, X-ray scattering is likely to occur in the filter unit, that is, scattered X-rays are easily emitted from the filter unit to the outside. In order to shield the scattered X-rays only by the housing of the filter unit, it is necessary to configure the entire housing with a sufficient thickness. Since a high voltage is applied to the X-ray generator, electromagnetic noise is likely to be generated in the X-ray generator. Therefore, it is expected to eliminate or reduce the leakage of this electromagnetic noise. In addition, it is also desired that the X-ray generator can be easily transported. It is required to solve at least one of the problems enumerated above.

method used to solve the problem

An object of the present invention is to provide an X-ray generator capable of effectively shielding scattered X-rays while dissipating heat. Alternatively, an object of the present invention is to provide a highly practical X-ray generator.

The X-ray generating device according to the present invention includes: an X-ray generating unit having an X-ray generating source and a shielding case, wherein the X-ray generating source generates an X-ray beam, and the shielding case accommodates the X-ray Generating a source and having a front panel with an X-ray irradiation port; a filter unit, which is arranged on the front panel in the X-ray generating unit, and has at least one filter, and inserts the at least one filter On the path of the X-ray beam; a heat dissipation structure disposed on the front panel and disposed around the filter unit.

According to the above configuration, the heat dissipation structure to which heat from the X-ray generator is transmitted is provided around the filter unit, and the cooling of the X-ray generator can be promoted by the heat dissipation effect of the heat dissipation structure. One or more filters are driven in the filter unit, and scattered X-rays are easily generated in various directions due to the passing state of the X-ray beam in the filter unit. Among such scattered X-rays, most of the scattered X-rays pass through the heat dissipation structure provided around the filter unit, so the shielding effect of the scattered X-rays in the heat dissipation structure can be expected. Since when a unit having a cylindrical filter drum is used as a filter unit, scattered X-rays tend to be randomly generated over a wide area, so in this case, the heat dissipation structure serves as an X-ray shielding member and function more effectively.

Preferably, the heat dissipation structure includes: a plurality of vertical walls, which stand up relative to the front panel; at least one horizontal wall, which is parallel to the front panel, and the plurality of vertical walls have an X-ray attenuating effect and the horizontal wall is made of X-ray attenuating material. Although only a plurality of vertical walls can be provided when only the cooling effect is required, when the shielding effect is also required, it is preferable to also provide horizontal walls, that is, it is preferable to scatter the radiation emitted to each direction of the horizontal direction and the vertical direction. The structure of the heat dissipation structure is determined by the manner in which the X-rays traverse any shielding member. The effect of shielding scattered X-rays can be further enhanced by providing a heat dissipation structure and setting the entire or part of the casing of the filter unit thick. In addition, a plurality of cooling fins may be provided on the surface of the filter unit housing.

Preferably, the heat dissipation structure has a plurality of ducts, and the interior of each of the ducts functions as an air circulation channel, and the X-ray generating device is provided with a device for allowing the air to pass through the plurality of ducts. The air supply unit circulating in the channel. Appropriate air flow is formed through a plurality of passages and air supply units, thereby promoting air cooling. Preferably, a cable for supplying power to the X-ray generating source is inserted through a specific channel among the plurality of channels. Accordingly, the electromagnetic shielding effect of the heat dissipation structure can be expected. Even if the entire cable is not housed in the tunnel, if a part of the cable is housed in the tunnel, at least that part can prevent or reduce the leakage of electromagnetic waves.

In addition, the end portion of the horizontal wall may be extended horizontally to function as a handle. In addition, the ends of each vertical wall may be shaped like a spire to facilitate air circulation. Although the above configuration can be applied to various devices using X-rays, it is particularly preferably applied to a bone density measurement device (bone mineral mass measurement device).

Description of drawings

FIG. 1 is a block diagram showing a bone density measurement system including an X-ray generator according to the present invention.

Fig. 2 is a sectional view of the upper unit.

Fig. 3 is a diagram showing a rotating drum in a filter unit.

Figure 4 is a top view of the upper unit.

FIG. 5 is a diagram showing a modified example of the structure.

FIG. 6 is a diagram showing another modified example of the structure.

detailed description

Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.

FIG. 1 illustrates a bone density measurement system including an X-ray generator according to the present invention. This bone density measurement system is a system installed in a medical institution. The X-ray generating device according to the present invention can be applied to other systems using X-rays besides the bone density measurement system.

The bone density measurement system shown in FIG. 1 is a system for measuring the amount of bone mineral in a subject's skeleton. This system is generally constituted by a measurement unit 10 and an arithmetic control unit 12 . The measuring unit 10 is a part that acquires X-ray detection data for calculation of bone mineral mass by irradiating and detecting X-rays. The arithmetic control unit 12 is a part that controls the detection unit 10 and processes detection data.

The measurement unit 10 will be described in detail. The measuring unit 10 includes an X-ray generating unit 14 and an upper unit 18 . Specifically, the above-mentioned units 14 , 18 are provided on the lower portion of the platform 20 . An X-ray generator is configured by combining the X-ray generator unit 14 and the upper unit 18 . Its detailed structure will be described in detail later using FIGS. 2 to 4 . The X-ray generating unit 14 includes an X-ray generating tube 16 , and generates X-rays in the X-ray generating tube 16 , specifically, X-rays having a fan beam shape. In the present embodiment, the upper unit 18 includes a filter unit and a structure (radiation structure). As will be described in detail later, the structural body exerts a heat dissipation function, a shielding function, an electromagnetic shielding function, and the like.

A subject 22 is placed on the platform 20 . In FIG. 1 , a fan-shaped ray beam extending on the YZ plane is illustrated. An X-ray detection unit 24 is provided above the subject 22 . The X-ray detection unit 24 is a unit constituted by a plurality of detection sensors. The X-ray detection unit 24 outputs detection data. Reference numeral 26 denotes a housing in the measurement section. In this embodiment, the X-ray generation unit 14, the upper unit 18, and the X-ray detection unit 24 are conveyed in the horizontal direction by a scanning mechanism not shown. An X-ray generator may be provided above the subject, and an X-ray detection unit may be provided below the subject.

Next, the arithmetic control unit 12 will be described. The control part 30 is a part which controls the operation|movement of the whole system, and implements control especially to the power supply 32 and a filter unit. The bone density calculation unit 28 calculates bone density using first detection data obtained by irradiating high-energy X-rays and second detection data obtained by irradiating low-energy X-rays. The bone density image thus obtained is output to the display unit 34 . On the display unit 34 , in addition to displaying the bone density image, an average bone density value and the like are displayed as numerical values. In addition, the voltage of the power supply is switched and the rotational operation of the filter is controlled according to the irradiation of high-energy X-rays and the irradiation of low-energy X-rays.

In FIG. 2 , a cross section of the upper unit 18 shown in FIG. 1 is illustrated. The lower side thereof is the X-ray generating unit 14 . The X-ray generating unit 14 includes a housing 38 made of a material having an X-ray shielding effect, such as brass or lead. The inside 40 of the case 38 is filled with insulating oil, and the X-ray generating tube 16 is provided inside the case 38 . Insulating oil plays the role of heat dissipation and insulation. A slit 38A that functions as a radiation port through which the X-ray beam 36 passes is formed on a top plate 38B serving as a front plate in the casing 38 . The slit 38A has a structure that does not allow insulating oil to flow out. The top plate 38B is a member extending along the XY plane (that is, parallel to the XY plane).

The upper unit 18 includes a filter unit 42 and a structure 44 . Specifically, the structure body 44 is provided so as to surround the periphery of the filter unit 42 . The filter unit 42 has a rotary drum 46 provided therein, and the rotary drum 46 has a plurality of filter members. This part will be described later using FIG. 3 . Around the rotary drum 46, a filter unit case 48 is provided, and the filter unit case 48 has a side panel 48B and an upper panel 48A. The upper panel 48A is formed slightly thicker than the side panels 48B, and a slit 48C through which the X-ray beam 36 passes is formed at the center of the upper panel 48A. The slit 48C functions as a collimator. A plurality of cooling fins 50 are formed on the outer surface of the side panel 48B. As a result, the heat dissipation effect of the filter unit housing 48 is enhanced. The filter unit housing 48 is made of, for example, brass or lead, that is, a material having an X-ray shielding effect. The thickness of the upper panel 48A is sufficiently large so that scattered X-rays do not leak upward from the inside of the filter unit 42 . In addition, arrows indicated by reference numeral 56 conceptually illustrate scattered X-rays emitted from the rotating drum in the horizontal direction. The rotation axis of the rotary drum is parallel to the Y direction.

In the example shown in FIG. 2 , the structure 44 has a horizontal plate 52 and a plurality of vertical plates 54 integrated with the horizontal plate 52 . The horizontal plate 52 is a member extending along the XY plane. Each vertical plate 54 is a member extending along the YZ plane. A plurality of passages 60 partitioned by a plurality of vertical plates 54 are formed below the horizontal plate 52 . Each channel 60 functions as an air circulation channel. Cables 58 are respectively inserted through the two channels at the right end and the left end in the channel column. These cables 58 are the cables that supply power to the two fans that circulate the air.

In FIG. 2 , the electromagnetic shielding effect on the channel 60 through which the cable 58 is passed is indicated by the symbol 62 . The structure 44 is made of a member that blocks or weakens scattered X-rays, and is made of metal such as lead or brass. Of course, the structural body 44 may also be constituted by members such as aluminum. In any case, it is preferable that the structural body 44 is constituted by a member that blocks or attenuates X-rays. Since a plurality of vertical plates 54 are arranged in the horizontal direction in the structural body 44, the attenuation effect on X-rays is enhanced in the horizontal direction. Since the structural body 44 has the horizontal plate 52 having a somewhat thicker thickness, an attenuation effect of X-rays in the vertical direction is also obtained. Although it is impossible to expect the structure 44 to attenuate the X-rays emitted in the Y direction (that is, the direction perpendicular to the paper surface of FIG. 2 ) when viewed from the filter unit 42, in order to weaken such X-rays, The thicknesses of the two side panels at both end portions in the Y direction of the filter unit case 48 are increased. That is, in the filter unit case 48 , the thickness of the upper panel 48A and the thickness of the two side panels aligned in the Y direction are increased. In other words, the thicknesses of the two perpendicular side panels located at both ends in the X direction become thinner. However, the scattered X-rays passing through these side plates are sufficiently attenuated by the above-mentioned plurality of vertical plates 54 and the like.

As mentioned above, the structure 44 is composed of a horizontal plate 52 and a plurality of vertical plates 54 to increase the surface area of the structure 44 . Thereby, a sufficient heat dissipation effect can be produced in the structural body 44 . The structural body 44 is connected to the case 38 in the X-ray generating unit 14 , specifically, to the top plate 38B. Therefore, the heat generated by the X-ray generating tube 16 is transferred to the case 38 via the insulating oil, and is further transferred from the case 38 to the structure 44 . The heat generated by the X-ray generating tube 16 is efficiently discharged to the outside by the heat radiation effect of the structure body 44 . In order to further promote this cooling effect, a plurality of fans which will be described below are provided.

In FIG. 3 , the rotary drum 46 is schematically illustrated. The rotating drum 46 is provided in the filter unit 42 shown in FIG. 2 . Rotary drum 46 has a plurality of members 104 and 106 and a plurality of openings 102 arranged along the circumferential direction. Part 104 is a filter or shielding part, and part 106 is a filter part. In this way, by arranging a plurality of members in the circumferential direction or providing the opening 102 between adjacent members, it is possible to perform filtering for generating high-energy X-rays and low-energy X-rays. For example, when looking at part 104, X-rays hit edge 104A of part 104 at a particular rotational angle, thereby generating scattered X-rays in various directions. In FIG. 3 , these scattered X-rays are indicated by a plurality of dashed lines marked with arrows. As shown in FIG. 2 , such scattered x-rays are firstly attenuated in the filter unit housing 48 . In addition, scattered X-rays emitted in the horizontal direction, particularly in the X direction, are effectively blocked by the structures 44 .

In Fig. 4, a top view of the upper unit is illustrated. As mentioned above, the upper unit has a structure 44 with a horizontal plate 52 and a plurality of vertical plates 54 . And a plurality of channels 60 are formed through these plates. In FIG. 4, each channel 60 is a wind tunnel extending in the Y direction. A plurality of fans 62A, 62B are provided on one side (left side in FIG. 4 ) of the plurality of ducts 60 , and air is forcibly sent to the plurality of ducts 60 by these fans 62A, 62B. The flow of air is indicated in FIG. 4 by a number of arrows. The blown air is sent not only to the plurality of ducts 60 but also to the plurality of grooves formed on the upper side of the horizontal plate 52 . Therefore, the effect of heat dissipation is effectively exerted on the entire surface of the structure body 44 . In addition, reference numeral 58 denotes cables connected to the two fans 62A, 62B. The main part of this cable 58 is led into a specific channel. Structural parts existing around this particular channel will perform an electromagnetic shielding effect. Thereby, leakage of electromagnetic noise can be prevented or reduced. In addition, one end of each cable 58 is connected to each fan, and the lower end of each cable 58 is led into the X-ray generating unit. A part of bundled cables (not shown) extending from the X-ray generating unit serves as a power supply cable for the fan.

In FIG. 4 , the end portion in the Y direction of the filter unit case in the filter unit 48 , that is, the side plate 48D is thicker than the side plate 48B at the end portion in the X direction. When scattered X-rays are generated in the axial direction of the rotary drum, that is, in the Y direction, the scattered X-rays are blocked by the side panel 48D.

In FIGS. 5 and 6 , two modification examples related to the structure body 44 are shown. The structure 44 shown in FIG. 5 is the same as the structure shown in FIG. 2 , and includes a horizontal plate 52 and a plurality of vertical plates 54 . However, in the example shown in FIG. 5 , both ends in the Y direction of the horizontal plate 52 extend in the horizontal direction. The two extensions are horizontally protruding portions which will function as handles 52A, 52B. The X-ray generating unit 14 and the upper unit 18 are structurally linked. By gripping the pair of handle parts, the entire X-ray generator can be firmly grasped and transported.

In the modified example shown in FIG. 6 , the air inlet side end portion of each vertical plate 54 has a pointed shape 54 a, that is, the resistance when air is introduced becomes small. Although in the above-mentioned embodiment, the structure is composed of one horizontal plate and a plurality of vertical plates, one or more horizontal plates can also be added, and more complicated structures can also be adopted in order to increase the surface area of the structure . Regardless of which structure is adopted, it is preferable to adopt a structure that effectively produces a heat dissipation effect and a shielding effect. Although in the above embodiment, no structural body is provided on the upper part of the filter unit, the structure of the structural body can also be changed so that the attenuation function and heat dissipation function can also be exerted in this part.

Claims (7)

1. An X-ray generating device, characterized in that, comprising: The X-ray generating unit has an X-ray generating source, a shielding housing, and insulating oil, wherein the X-ray generating source generates an X-ray beam, and the shielding housing accommodates the X-ray generating source and is equipped with an X-ray irradiation device. The front panel of the port, the insulating oil is filled inside the shielding housing: a filter unit provided on the front panel of the X-ray generating unit, having a rotating drum provided with at least one filter, and inserting the at least one filter on the path of the X-ray beam ; a heat dissipation structure disposed around the filter unit on the front panel, and used to shield scattered X-rays generated in the filter unit and air-cool the X-ray generating unit , The heat dissipation structure includes: a plurality of vertical walls upstanding relative to the front panel; at least one horizontal wall parallel to the front panel, a plurality of said vertical walls are made of X-ray attenuating material and said horizontal walls are made of X-ray attenuating material, The heat dissipation structure has a plurality of channels, The interior of each of the channels functions as an air circulation channel. 2. The X-ray generating device according to claim 1, wherein: An air supply unit for circulating air through the plurality of passages is provided in the X-ray generator. 3. The X-ray generating device according to claim 2, wherein: A cable for supplying power to the X-ray generating source is inserted through a specific channel among the plurality of channels. 4. The X-ray generating device according to claim 1, wherein: The front panel is a component extending along the XY plane, an X-ray beam extending along the YZ plane is output from the X-ray irradiation port, Each of the vertical walls is a member extending along the YZ plane, The at least one horizontal wall is a component extending along the XY plane. 5. The X-ray generating device according to claim 1, wherein: At least one of the one end and the other end of each of the vertical walls has a pointed shape. 6. The X-ray generating device according to claim 1, wherein: One end and the other end of the horizontal wall function as a handle. 7. The X-ray generating device according to claim 1, wherein: The X-ray generating device is a device applied in a bone density measurement system.