JP2024078759A - Radiation diagnostic equipment - Google Patents

Abstract

The present invention provides a radiation diagnostic apparatus that can be cooled while ensuring uniformity in temperature in a heat generating element even when the operating state of the radiation diagnostic apparatus changes.
[Solution] A radiological diagnostic apparatus according to an embodiment includes a heating element, a heat sink, a duct, and a fan. The duct is attached to the heating element, houses the heat sink on the heating element side, and has an intake opening and an exhaust opening smaller than the intake opening. The fan is provided at least one of the intake opening and the exhaust opening of the duct. The duct has a deformation mechanism that deforms an internal space of the duct based on the temperature distribution of the heating element.
[Selected figure] Figure 2

Description

The embodiments disclosed in this specification and the drawings relate to a radiological diagnostic device.

The components that make up radiological diagnostic devices, such as PET (Positron Emission Tomography) devices, contain heating elements that generate heat in response to operation. For example, when radiation is irradiated, the detection elements and circuit boards of a radiation detector generate heat. For this reason, it is preferable to cool these types of heating elements to prevent deterioration in the quality of captured images and malfunctions caused by heat generated by these heating elements.

One method for cooling a heat-generating body is to use a heat sink. Figure 9 shows an example in which a rectangular heat sink 3 with slits is provided inside a rectangular duct 4c whose upstream and downstream ends are open as an intake opening and an exhaust opening of the same shape, respectively. In this case, the heat sink 3 can be cooled by passing air through the inside of the duct 4c. Therefore, the duct 4c is placed in contact with a heat-generating body (not shown in Figure 9, for example, a detector module) and air is passed through the duct 4c, allowing the heat-generating body to be cooled via the heat sink 3.

However, when using a duct 4c with the shape shown in FIG. 9, when cold air flows through the duct 4c, the temperature on the windward side decreases, but the temperature on the leeward side increases due to heat dissipation from the heat sink 3. For this reason, it is difficult to ensure temperature uniformity from the windward side to the leeward side of the heat sink 3.

Japanese Patent Application Laid-Open No. 9-307040

One of the problems that the embodiments disclosed in this specification and the drawings attempt to solve is to ensure temperature uniformity in the heating element while cooling it, even if the operating state of the radiation diagnostic device changes. However, the problems that the embodiments disclosed in this specification and the drawings attempt to solve are not limited to the above problem. Problems corresponding to the effects of each configuration shown in each embodiment described below can also be positioned as other problems.

The radiological diagnostic device according to the embodiment includes a heating element, a heat sink, a duct, and a fan. The duct is attached to the heating element, houses the heat sink on the heating element side, and has an intake opening and an exhaust opening smaller than the intake opening. The fan is provided at least one of the intake opening and the exhaust opening of the duct. The duct has a deformation mechanism that deforms the internal space of the duct based on the temperature distribution of the heating element.

FIG. 1 is a perspective view showing the appearance of a radiation diagnostic apparatus according to a first embodiment. FIG. 2 is a cross-sectional view showing a structure of a duct according to the first embodiment. FIG. 3 is a flowchart showing the operation of the deformation mechanism according to the first embodiment. FIG. 4 is a cross-sectional view showing an example of a deformation mechanism according to the first embodiment. FIG. 5 is a cross-sectional view showing another example of the deformation mechanism according to the first embodiment. FIG. 6 is a cross-sectional view showing a structure of a duct according to the second embodiment. FIG. 7 is a cross-sectional view showing a structure of a duct according to a third embodiment. FIG. 8 is a diagram showing a simulation result of the first embodiment. FIG. 9 is a perspective view showing the appearance of a radiation diagnostic apparatus according to a conventional technique.

Below, an embodiment of the radiation diagnostic device will be described in detail with reference to the drawings.

[Embodiment 1]
The first embodiment relates to a radiological diagnostic apparatus 1 in which the internal space of a duct is deformed by connecting two members with a rotation mechanism.

FIG. 1 is a perspective view showing the appearance of a radiation diagnostic device 1 according to the first embodiment. The radiation diagnostic device 1 is a PET (Positron Emission Tomography) device, a SPECT (Single Photon Emission Computed Tomography) device, an X-ray CT (Computed Tomography) device, or the like.

The radiation diagnostic device 1 includes a radiation detector 2, a heat sink 3, a duct 4, and a fan 5. When the radiation diagnostic device 1 is a PET device, the radiation detector 2 is a gamma ray detector that detects gamma rays, and multiple radiation detectors are installed. The radiation detector 2 is an example of a heating element. In FIG. 1, the front side and top of the duct 4 are cut away to show the internal structure of the duct 4.

For example, if the radiation detector 2 is a gamma ray detector that detects gamma rays, the radiation detector 2 has a collimator for determining the angle of incidence of gamma rays, a scintillator that emits a momentary flash of light when gamma rays collimated by the collimator are incident on it, a light guide, a plurality of photomultiplier tubes arranged two-dimensionally to detect the light emitted from the scintillator, and an electronic circuit for the scintillator. The scintillator is made of, for example, thallium-activated sodium iodide NaI (Tl).

The heat sink 3 has, for example, a rectangular parallelepiped shape with multiple slits penetrating from the windward side to the leeward side, and performs cooling by dissipating (radiating) the absorbed heat into the air. The multiple slits in the heat sink 3 are provided, for example, by dividing the inside of the heat sink 3 with multiple fins.

The duct 4 has one side attached to the multiple radiation detectors 2, houses the heat sink 3 on the radiation detector 2 side, and has an intake opening 41, an exhaust opening 42, and a deformation mechanism 43. The intake opening 41 is an opening for taking in air from outside the duct 4 into the duct 4, and is formed to have a height greater than that of the heat sink 3. The exhaust opening 42 is an opening for discharging air from inside the duct 4, and is formed to have a smaller size than the intake opening 41 (for example, a size having a height approximately equal to that of the heat sink 3). The distance between the intake opening 41 and the exhaust opening 42 is, for example, 200 mm. The deformation mechanism 43 deforms the internal space of the duct 4 based on the temperature distribution of the multiple radiation detectors 2. Details of the deformation mechanism 43 will be described later.

The fan 5 is provided in the exhaust opening 42 of the duct 4 and exhausts the air inside the duct 4. The fan 5 may be provided in at least one of the intake opening 41 and the exhaust opening 42 of the duct 4. That is, the fan 5 may be provided in the intake opening 41 of the duct 4 and may take in air outside the duct 4. The fan 5 may also be provided in both the intake opening 41 and the exhaust opening 42 of the duct 4, so that the fan 5 provided in the intake opening 41 takes in air outside the duct 4 and the fan 5 provided in the exhaust opening 42 exhausts the air inside the duct 4.

The temperature rise ΔT of the air to be cooled is calculated by the formula (1).
ΔT = W / (Cp ρ Q) ... (1)
where W is the heat generation amount of the heating element [W], Cp is the specific heat at constant pressure of air [kJ/kg·°C], ρ is the density of air [kg/m ³ ], and Q is the air volume [m ³ /s] passing between the fins of the heat sink 3. For example, when using a duct 4 with a small flow path cross-sectional area from the exhaust opening 42 toward the intake opening 41 as shown in Fig. 1, the air volume Q passing between the fins of the heat sink 3 can be made larger toward the exhaust opening 42.

The temperature rise ΔT′ during heat dissipation through heat transfer is calculated by the formula (2).
ΔT' = W/S h (2)
Here, S is the area [m ² ], and h is the thermal conductivity [W/m·K].

In this way, it can be seen that the overall temperature rise can be adjusted by adjusting the temperature ΔT and air flow rate Q of the air passing through the heat sink 3. Therefore, the radiological diagnostic device 1 according to the embodiment changes the internal shape of the duct 4 in accordance with the operating state of the radiological diagnostic device 1, i.e., the heat generation state of the heating element, so as to uniformly cool the heating element attached from the windward side to the leeward side of the duct 4.

Figure 2 is a cross-sectional view showing the structure of the duct 4 according to the first embodiment. The temperature distribution of the radiation detector 2 is preferably obtained by directly measuring the temperature of the radiation detector 2, but as shown in Figure 2, it may also be estimated from the temperatures at multiple locations on the inner surface of the inner surface of the duct 4 on the radiation detector 2 side on which the heat sink 3 is placed. In this case, as shown in Figure 2, the temperature sensors 6 are installed at multiple locations from upwind to downwind between the bottom surface of the heat sink 3 and the inner surface of the duct 4 on the radiation detector 2 side. Each temperature sensor 6 outputs temperature measurement data to the control function 435.

The deformation mechanism 43 deforms the internal space of the duct 4 in accordance with the temperature distribution on the radiation detector 2 side. The deformation mechanism 43 deforms the shape of the inner surface of the internal space of the duct 4 that faces the radiation detector 2 side. The deformation mechanism 43 includes plate-like members 431, 432, a rotation mechanism 433, a movement mechanism 434, a control function 435, and support parts 436, 437.

The plate-like members 431 and 432 of the deformation mechanism 43 constitute the inner surface of the duct 4 that faces the inner surface on the radiation detector 2 side. The plate-like members 431 and 432 are an example of a plurality of parts. The rotation mechanism 433 connects the plate-like members 431 and 432 so that they can rotate freely around the rotation mechanism 433 as an axis. For example, the angle between the plate-like members 431 and 432 is changed to an arbitrary angle by the rotation mechanism 433 moving up and down. The rotation mechanism 433 can be configured using, for example, a hinge. The rotation mechanism 433 is an example of a connection part. Note that the number of plate-like members is not limited to two, and may be three or more. For example, when there are three plate-like members, two rotation mechanisms are used. By increasing the number of plate-like members, the degree of freedom of the shape of the inner surface that faces the inner surface on the radiation detector 2 side of the duct 4 can be increased.

The moving mechanism 434 includes a mechanism for moving the rotating mechanism 433 in a direction toward or away from the radiation detector 2 under the control of the control function 435. As shown in FIG. 2, the moving mechanism 434 moves the rotating mechanism 433, for example, in a vertical direction (a direction perpendicular to the inner surface on the radiation detector 2 side). The moving mechanism 434 is, for example, a rack and pinion that converts the rotational motion of a motor into the vertical motion, and is an example of a power unit.

The control function 435 includes a function of acquiring data indicating temperature measurement values from the multiple temperature sensors 6, and controlling the movement mechanism 434 to move the rotation mechanism 433 vertically according to the temperature distribution on the radiation detector 2 side inside the duct 4. The movement mechanism 434 and the control function 435 may be provided in the space formed by the upper side surfaces of the plate-like members 431 and 432 and the duct 4 (see the dead space (above the plate-like members 431 and 432) in the upper right of Figure 1).

The control function 435 is realized by the processor reading and executing a program stored in a storage medium such as a RAM and a ROM. In addition to the program, the storage medium may store a table that associates the imaging conditions with the amount of deformation of the internal space of the duct 4 caused by the deformation mechanism 43. The storage medium is an example of a memory unit.

This table may be updated by the control function 435 for each shooting. Specifically, the control function 435 may update the amount of deformation stored in the table in association with the shooting conditions for each shooting with the amount of deformation of the internal space at the end of shooting as a result of the deformation performed by the deformation mechanism by shooting the corresponding shooting. An example of updating the table will be described later with reference to FIG. 3. The control function 435 is an example of a control unit.

The support part 436 supports the left end part of the plate-like member 431, i.e., the end part of the plate-like member 431 opposite the rotation mechanism 433. The support part 436 has, for example, a U-shaped cross section. The support part 437 supports the right end part of the plate-like member 432, i.e., the end part of the plate-like member 432 opposite the rotation mechanism 433. The support part 437 has, for example, a U-shaped cross section.

The left end of plate-like member 431 and the right end of plate-like member 432 are pulled out from or pushed into support parts 436, 437 in response to the vertical movement of rotation mechanism 433. Support parts 436, 437 shown in FIG. 2 allow movement that changes the angle by providing a gap between them and plate-like members 431, 432 in the thickness direction. In addition, support parts 436, 437 are long enough to prevent plate-like members 431, 432 from falling off.

As described above, when using a duct 4 with a smaller flow cross-sectional area from the exhaust opening 42 to the intake opening 41 as shown in FIG. 1, the air volume Q can be increased toward the exhaust opening 42. Also, the space on the intake opening 41 side is easily cooled by the freshly taken-in outside air. In other words, the central part inside the duct 4 is more difficult to cool and more likely to become hot than the intake opening 41 side and the exhaust opening 42 side. Therefore, by moving the rotating mechanism 433 downward and reducing the flow cross-sectional area directly below the rotating mechanism 433, the internal space in the central part, which becomes hot, can be more easily cooled.

Fig. 3 is a flowchart showing the operation of the deformation mechanism 43 according to embodiment 1. Fig. 3 shows the processing of the control function 435 of the radiation diagnostic apparatus 1 and the operation of the deformation mechanism 43 in response to the processing.

In step S1, the control function 435 acquires the set imaging conditions. The imaging conditions include, for example, information such as the scan method, slice thickness, window level, and window width. The control function 435 may acquire imaging conditions manually set by the user via a console, or may acquire imaging conditions that are included in an examination order or the like and automatically set.

In step S2, the control function 435 sets the initial position of the rotation mechanism 433 in the movement mechanism 434. The movement mechanism 434 receives the initial position setting from the control function 435 and moves the rotation mechanism 433 to the initial position.

Specifically, the control function 435 obtains the value of the movement amount of the rotation mechanism 433 associated with the shooting conditions set in step S1 from a table stored in a storage medium in which the shooting conditions are associated with the movement amount of the rotation mechanism 433, and uses this value to determine the initial position. As the initial value of the movement amount stored in the table, for example, a reference position is used. This initial value is adaptively updated for each shooting by replacing it with the movement amount in the shooting actually performed in step S11.

In step S3, the control function 435 obtains the temperature measurement values on the radiation detector 2 side inside the duct 4 from multiple temperature sensors 6 installed between the intake opening 41 and the exhaust opening 42. Note that the temperature sensors 6 do not need to correspond one-to-one with the radiation detectors 2. The temperature sensors 6 may be installed directly below the rotation mechanism 433 (at the midpoint in the example with two plate-shaped members shown in FIG. 2) (see FIG. 2).

In step S4, the control function 435 determines whether the range of temperature measurements at multiple locations (hereinafter referred to as the temperature range) is within a reference value. The temperature range is, for example, the maximum value minus the minimum value of the temperature measurements, and is an example of the maximum difference in temperature. If the temperature range is within the reference value (YES in step S4), the control function 435 proceeds to processing in step S9. On the other hand, if the temperature range is greater than the reference value (NO in step S4), the control function 435 proceeds to processing in step S5. The control function 435 may also determine whether the temperature at a specified point (for example, directly below the rotation mechanism 433) is between a lower threshold and an upper threshold.

In step S5, the control function 435 receives a control signal indicating the position of the rotation mechanism 433 from the movement mechanism 434.

In step S6, the control function 435 transmits a control signal to the movement mechanism 434 to change the position of the rotation mechanism 433 according to the temperature range. The movement mechanism 434 receives a control signal from the control function 435 and moves the rotation mechanism 433 to the position indicated by the control signal. For example, when the temperature range measured at multiple locations is greater than a reference value, the deformation mechanism 43 lowers the rotation mechanism 433 to increase the cooling efficiency by reducing the internal space of the duct 4.

The control function 435 may send a control signal to the movement mechanism 434 to move the rotation mechanism 433 downward (in a direction perpendicular to the inner surface on the radiation detector 2 side and approaching the inner surface) when the temperature at a specified point (for example, directly below the rotation mechanism 433) exceeds an upper threshold, and to move the rotation mechanism 433 upward when the temperature at the specified point falls below a lower threshold. That is, the deformation mechanism 43 may deform the internal space of the duct 4 to make it smaller or larger depending on the comparison result between the temperature measured at the specified point and the upper and lower thresholds.

In step S7, the rotation mechanism 433 moves, thereby changing the shape of the top surface of the duct 4 (the inner surface facing the inner surface on the radiation detector 2 side). For example, when the rotation mechanism 433 moves downward, the central portion of the top surface of the duct 4 moves downward, changing to a concave shape. This reduces the internal space of the duct 4. On the other hand, when the rotation mechanism 433 moves upward, the central portion of the top surface of the duct 4 moves upward, changing to a protruding shape. This increases the internal space of the duct 4.

In step S8, the temperature inside the duct 4 changes as the central portion of the top surface of the duct 4 moves up and down. For example, when the central portion moves down, the temperature inside the duct 4 decreases. On the other hand, when the central portion moves up, the temperature inside the duct 4 increases.

In step S9, the control function 435 waits for a certain period of time to elapse. When the certain period of time has elapsed, the control function 435 proceeds to the processing of step S10. As a result, the processing of steps S3 to S8 is performed at regular intervals unless the control is terminated as determined in step S10.

In step S10, the control function 435 determines whether or not control has ended. For example, if the user has instructed to end temperature control or if the operation of the radiation diagnostic device 1 has ended, it is determined that control has ended. If control has not ended (NO in step S10), the control function 435 returns to the processing of step S3.

On the other hand, if control is to end (YES in step S10), the control function 435 stores in the table stored in the storage medium the current shooting conditions and the final movement amount of the rotation mechanism 433, i.e., the movement amount of the rotation mechanism 433 that minimizes temperature variation, in association with each other. In this way, by repeating steps S1-S11 for each shooting, the table associating the shooting conditions with the optimal movement amount of the rotation mechanism 433 is updated. Therefore, in setting the initial position in step S2, the control function 435 can use a table that is repeatedly updated for each shooting and associates the optimal movement amount that reflects individual differences in the duct 4, etc.

Figure 4 is a cross-sectional view showing an example of the deformation mechanism 43 according to the first embodiment. In the example shown in Figure 4, the support parts 436 and 437 are fixed. The rotation mechanism 433 can be moved only in the vertical direction by the movement mechanism 434 (see Figure 2), but cannot be moved in the horizontal direction.

In FIG. 4(A), the plate-like members 431 and 432 are positioned in a straight line, and form an angle of 180 degrees with the rotation mechanism 433 at the center. The left end of the lower surface of the plate-like member 431 is in contact with the lower inner surface of the support part 436. The right end of the lower surface of the plate-like member 432 is in contact with the lower inner surface of the support part 437. The position of the rotation mechanism 433 in this state may be used as the reference position.

In FIG. 4(B), the rotation mechanism 433 has moved downward from the position in FIG. 4(A). As the rotation mechanism 433 moves downward, the left end of the plate-shaped member 431 is pulled out from the support portion 436, and the angle with the plane parallel to the inner surface on the radiation detector 2 side (hereinafter referred to as the horizontal plane) becomes larger than in the state in FIG. 4(A). Meanwhile, the support portion 436 remains fixed. As a result, the left end of the lower surface of the plate-shaped member 431 is separated from the lower inner surface of the support portion 436 and is in a floating state, and the lower surface of the plate-shaped member 431 is supported by the right tip of the lower inner surface of the support portion 436.

On the other hand, as the rotating mechanism 433 moves downward, the right end of the plate-like member 432 is pushed into the support portion 437, and the angle with the horizontal plane becomes smaller than in the state of Fig. 4(A). Meanwhile, the support portion 437 remains fixed. As a result, the right tip of the lower surface of the plate-like member 432 moves away from the lower inner surface of the support portion 437, and the lower surface of the plate-like member 432 is supported by the left tip of the lower inner surface of the support portion 437.
By the above operation, the plate-like members 431 and 432 are recessed near the rotating mechanism 433 .

In FIG. 4(C), the rotation mechanism 433 has moved upward from the position in FIG. 4(A). As the rotation mechanism 433 moves upward, the left end of the plate-shaped member 431 is pushed deeper into the support portion 436, and the angle with the horizontal plane becomes smaller than in the state of FIG. 4(A). Meanwhile, the support portion 436 remains fixed. As a result, all but the left tip of the left end of the lower surface of the plate-shaped member 431 is separated from the lower inner surface of the support portion 436, and only the left tip of the lower surface of the plate-shaped member 431 is supported by the lower inner surface of the support portion 436.

As the rotation mechanism 433 moves upward, the right end of the plate-like member 432 is pulled out from the support portion 437, and the angle with the horizontal plane becomes larger than in the state of FIG. 4A. Meanwhile, the support portion 437 remains fixed. As a result, the right end of the lower surface of the plate-like member 432, except for the right tip, moves away from the lower inner surface of the support portion 437, and only the right tip of the lower surface of the plate-like member 432 is supported by the lower inner surface of the support portion 437.
By the above operation, the plate-like members 431 and 432 are brought into a state in which the vicinity of the rotation mechanism 433 protrudes upward.

Figure 5 is a cross-sectional view showing another example of the deformation mechanism 43 according to the first embodiment. In the example shown in Figure 5, the support parts 436, 437 are rotatable in response to the vertical movement of the rotation mechanism 433. The plate-like member 431 slides while being sandwiched between the upper and lower inner surfaces of the support part 436 in response to the vertical movement of the rotation mechanism 433. Similarly, the plate-like member 432 slides while being sandwiched between the upper and lower inner surfaces of the support part 437 in response to the vertical movement of the rotation mechanism 433.

The rotation mechanism 433 can be moved only in the vertical direction by the movement mechanism 434 (see FIG. 2), as in the example shown in FIG. 4, and cannot be moved in the horizontal direction. Note that FIG. 4(A) is the initial state of the transformation mechanism 43.

In FIG. 5(A), the rotation mechanism 433 has moved downward from the position in FIG. 4(A). As the rotation mechanism 433 moves downward, the left end of the plate-shaped member 431 is pulled out from the support portion 436, and the angle with the horizontal plane becomes larger than in the state of FIG. 4(A). Accordingly, the support portion 436 rotates downward. As a result, the left end of the lower surface of the plate-shaped member 431 slides to be pulled out while remaining in contact with the lower inner surface of the support portion 436, and the area of contact between the left end of the lower surface of the plate-shaped member 431 and the lower inner surface of the support portion 436 decreases.

On the other hand, as the rotation mechanism 433 moves downward, the right end of the plate-like member 432 is pushed into the support portion 437, and the angle with the horizontal plane becomes smaller than in the state of Fig. 4(A). Accordingly, the support portion 437 rotates downward. As a result, the right end of the lower surface of the plate-like member 432 slides as if being pushed in while remaining in contact with the lower inner surface of the support portion 437, so that the contact area between the right end of the lower surface of the plate-like member 432 and the lower inner surface of the support portion 437 increases.
By the above operation, similarly to the example shown in FIG. 4B, the plate-like members 431 and 432 are recessed near the rotating mechanism 433 .

In FIG. 5(B), the rotation mechanism 433 has moved upward from the position in FIG. 4(A). As the rotation mechanism 433 moves upward, the left end of the plate-shaped member 431 is pushed deeper into the support portion 436, and the angle with the horizontal plane becomes smaller than in the state of FIG. 4(A). Accordingly, the support portion 436 rotates upward. As a result, the left end of the lower surface of the plate-shaped member 431 moves away from the right tip of the lower inner surface of the support portion 436 while remaining in contact with the lower inner surface of the support portion 436. In other words, the area of contact between the left end of the lower surface of the plate-shaped member 431 and the lower inner surface of the support portion 436 increases.

On the other hand, as the rotation mechanism 433 moves upward, the right end of the plate-shaped member 432 is pulled out from the support portion 437, and the angle with the horizontal plane becomes larger than in the state of Fig. 4(A). Accordingly, the support portion 437 rotates upward. As a result, the right end of the lower surface of the plate-shaped member 432 approaches the left tip of the lower inner surface of the support portion 437 while remaining in contact with the lower inner surface of the support portion 437. In other words, the area of contact between the right end of the lower surface of the plate-shaped member 432 and the lower inner surface of the support portion 437 decreases.
By the above operation, the plate-like members 431 and 432 are brought into a state in which the vicinity of the rotation mechanism 433 protrudes.

[Embodiment 2]
The second embodiment relates to a radiological diagnostic device 1a that deforms the internal space of a duct by an elastically deformable material. This embodiment differs from the first embodiment in that a deformation mechanism 43a has an elastically deformable member. The same components as those in the first embodiment are designated by the same reference numerals and will not be described.

Figure 6 is a cross-sectional view showing the structure of the duct 4a according to the second embodiment. As in the first embodiment, the duct 4a is attached to the radiation detector 2, houses the heat sink 3 on the radiation detector 2 side, and has an intake opening 41, an exhaust opening 42, and a deformation mechanism 43a.

The deformation mechanism 43a deforms the internal space of the duct 4a in accordance with the temperature distribution on the radiation detector 2 side. The deformation mechanism 43a includes a member 431a, a point of action 433a, a moving mechanism 434a, a control function 435, and support parts 436a and 437a.

The member 431a constitutes the inner surface of the duct 4a that faces the radiation detector 2. The member 431a is an elastic member that deforms when an external force is applied and returns to its original shape when the external force is removed, and may be made of, for example, rubber. In this case, the member 431a can be made of a single member. The point of action 433a is preferably located in the center of the member 431a in the longitudinal direction. Note that the point of action may be set in multiple locations.

The moving mechanism 434a includes a mechanism for moving the point of action 433a in a direction toward or away from the radiation detector 2 under the control of the control function 435. As shown in FIG. 6, the moving mechanism 434a moves the point of action 433a in the vertical direction. The moving mechanism 434a is, for example, a rack and pinion that converts the rotational motion of a motor into vertical motion.

The support portion 436a supports the left end portion of the member 431a. The support portion 437a supports the right end portion of the member 431a. The support portions 436a and 437a may be fixed or may be rotatable in response to the vertical movement of the action point 433a of the member 431a.

The processing of the control function 435 of the radiation diagnostic device 1a and the operation of the deformation mechanism 43a in response to this processing are the same as those in the first embodiment. On the other hand, the plate-like members 431, 432, the rotation mechanism 433, and the support parts 436, 437 in the first embodiment are replaced with the member 431a, the point of action 433a, and the support parts 436a, 437a in the second embodiment. The radiation diagnostic device 1a according to the second embodiment also achieves the same effects as the radiation diagnostic device 1a according to the first embodiment.

[Embodiment 3]
The third embodiment relates to a radiological diagnostic apparatus 1b that uses a bimetal to deform the internal space of a duct. This embodiment differs from the first embodiment in that a deformation mechanism 43b has a bimetal that undergoes thermal deformation. The same components as those in the first and second embodiments are designated by the same reference numerals and will not be described.

Figure 7 is a cross-sectional view showing the structure of the duct 4b according to the third embodiment. The duct 4b is attached to the radiation detector 2, houses the heat sink 3 on the radiation detector 2 side, and has an intake opening 41, an exhaust opening 42, and a deformation mechanism 43b.

The deformation mechanism 43b deforms the internal space of the duct 4b in accordance with the temperature distribution on the radiation detector 2 side. The deformation mechanism 43b includes a bimetal 431b and support parts 436b and 437b.

The bimetal 431b forms the inner surface facing the radiation detector 2, and deforms into a bow shape according to the temperature distribution in the internal space of the duct 4b. The bimetal 431b is installed so that it curves downward when the temperature in the internal space of the duct 4b rises due to heat generated by the heat sink 3. This reduces the internal space of the duct 4b, and adjusts the temperature of that internal space. Since the bimetal 431b curves autonomously in response to changes in the surrounding temperature, the deformation mechanism 43b does not require a movement mechanism or control function. A temperature sensor is also not required.

Support portion 436b supports the left end of bimetal 431b. Support portion 437b supports the right end of bimetal 431b. Since the angles of the left and right ends of bimetal 431b (e.g., the angle with respect to the horizontal plane) change depending on the curved state of bimetal 431b, it is preferable that support portions 436a and 437a are rotatable.

The bimetal 431b can adjust the amount of deformation in response to temperature changes by changing the shape, material, dimensions, etc. Here, the amount of deformation is the distance between the horizontal plane and the central part of the bimetal 431b curved upward when the bimetal 431b is placed on the horizontal plane. As an example, the bimetal 431b is made by forming stainless steel and aluminum members to a width of 2 mm, a length of 40 mm, and a thickness of 0.05 mm, respectively, and stacking the members. There is an analysis result that the amount of deformation of this bimetal 431b is 0.74 mm when the surrounding temperature is raised from 20°C to 40°C. The radiation diagnostic device 1a according to the third embodiment also achieves the same effect as the radiation diagnostic device 1a according to the first embodiment.

[Embodiment 4]
When it is estimated that the radiation detector 2 will generate heat due to the operation of the radiation diagnostic apparatus 1, the control function 435 may move the rotation mechanism 433 in advance according to the temperature change estimated by the operation via the movement mechanism 434 before the radiation diagnostic apparatus 1 actually starts operating. Note that the operation is not limited to an operation based on an operation by a user. For example, the control function 435 may determine whether or not to move the rotation mechanism 433 in advance based on the amount of heat generated by the radiation detector 2 in an examination to be performed, which is automatically estimated from a scan protocol or an examination order, and may determine the amount of movement to be made in advance if the rotation mechanism 433 is to be moved.

[Simulation result example]
Fig. 8 is a diagram showing the simulation results of embodiment 1. Fig. 8 shows the relationship between the temperature variation in duct 4 when the heat generation amount of radiation detector 2 is 1 to 3 [W] and the movement amount of rotation mechanism 433 shown in embodiment 1. The temperature variation is the difference between the maximum and minimum temperature values at each position in duct 4.

In this simulation, it was found that by moving the rotation mechanism 433 up and down within a range of -5 to 5 mm, it is possible to ensure temperature uniformity while maintaining efficient cooling. In particular, when the amount of heat generated by the radiation detector 2 is 1 W, it was found that the temperature variation is minimized when the amount of movement of the rotation mechanism 433 is -5 mm, i.e., when the rotation mechanism 433 is lowered 5 mm from the reference position (see the plot surrounded by the dashed circle in Figure 8). In this way, it is found that there is an optimal position for the rotation mechanism 433 depending on the amount of heat generated.

This simulation shows that even if the operating state of the radiation diagnostic device 1 (the amount of heat generated by a heating element such as the radiation detector 2) changes and the temperature of the heating element changes, the deformation mechanism 43 can be used to uniformly cool multiple points.

According to at least one of the embodiments described above, even if the operating state of the radiation diagnostic device changes, it is possible to cool the heating element while ensuring uniformity in temperature.

Although several embodiments have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These embodiments can be implemented in various other forms, and various omissions, substitutions, modifications, and combinations of embodiments can be made without departing from the spirit of the invention. These embodiments and their modifications are within the scope of the invention and its equivalents as set forth in the claims, as well as the scope and spirit of the invention.

1, 1a, 1b... Radiation diagnostic apparatus 2... Radiation detector 3... Heat sink 4, 4a, 4b... Duct 5... Fan 41... Intake opening 42... Exhaust opening 43, 43a, 43b... Deformation mechanism 431, 432... Plate-shaped member 431b... Bimetal 433... Rotation mechanism 434... Movement mechanism

Claims (10)

A heating element;
A heat sink;
a duct that is in contact with the heat generating element, that houses the heat sink on the heat generating element side, and that has an intake opening and an exhaust opening that is smaller than the intake opening;
a fan provided in at least one of the intake opening and the exhaust opening of the duct;
Equipped with
The duct is
a deformation mechanism that deforms an internal space of the duct based on a temperature distribution of the heating element;
A radiological diagnostic device having the above structure. The deformation mechanism deforms the internal space in accordance with a temperature distribution on the heating element side of the internal space.
The radiological diagnostic apparatus according to claim 1 . The deformation mechanism deforms the internal space so as to reduce the size when a maximum difference between temperatures measured at a plurality of points is greater than a threshold value.
The radiation diagnostic apparatus according to claim 2 . The deformation mechanism deforms the internal space in response to a comparison result between the temperature measured at a predetermined location and an upper threshold value and a lower threshold value.
The radiation diagnostic apparatus according to claim 2 . The deformation mechanism deforms a shape of an inner surface of the internal space of the duct that faces the heating element.
5. The radiation diagnostic apparatus according to claim 1. The deformation mechanism includes:
A plurality of components constituting an inner surface facing the heat generating element;
A connection portion that connects the plurality of components;
a power unit that moves the connection unit in a direction toward or away from the heating element in accordance with a temperature distribution in the internal space;
Equipped with
The radiation diagnostic apparatus according to claim 5. The deformation mechanism includes:
a bimetal that forms an inner surface facing the heating element and deforms into a bow shape in response to the temperature distribution in the internal space.
The radiation diagnostic apparatus according to claim 5. The heating element is a plurality of radiation detectors.
The radiation diagnostic apparatus according to claim 5. a storage unit that stores a table that associates the deformation amount of the internal space with an imaging condition;
a control unit that causes the storage unit to store, for each photograph, a photographing condition for the photographing and a deformation amount of the internal space in association with each other;
The radiation diagnostic apparatus according to claim 1 , further comprising: The control unit is
At the start of imaging, a deformation amount of the internal space associated with an imaging condition of the imaging in the table is given to the deformation mechanism as an initial value.
The radiation diagnostic apparatus according to claim 9.

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