Radiation image reader

Abstract

To hold an imaging plate in a regular posture.SOLUTION: A radiological image reader comprises a stage 60 that holds an imaging plate, an excitation light source, and a photo detector that detects emission light from the imaging plate. The stage has a stage body 61 that has a support surface 64F, and a pair of first direction positioning parts 72A, 72B. At least one of the pair of first direction positioning parts includes: a first direction positioning mechanism that moves along a first direction F1 as a first direction movable positioning part to sandwich the imaging plate on the support surface along the first direction; and a second direction positioning mechanism that has a lower positioning part 72C supporting the imaging plate on the support surface from below in a second direction F2 intersecting the first direction and closer to a gravity direction than the first direction, the lower positioning part moving along the second direction with respect to the stage body.SELECTED DRAWING: Figure 6

Description

[Technical Field]

[0001] This disclosure relates to a radiation image reading device. [Background technology]

[0002] Patent Document 1 discloses a radiation image reading device equipped with a transport mechanism for transporting an imaging plate. The transport mechanism includes a belt for holding the imaging plate and a belt drive mechanism for rotating the belt. The imaging plate is transported while placed on a holding surface that is part of the belt. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2011-53459 Summary of the Invention [Problem to be solved by the invention]

[0004] In a configuration in which an imaging plate is placed on the holding surface of a belt as in Patent Document 1, there is a possibility that the imaging plate may be held in an inclined position from the normal position suitable for reading a radiation image.

[0005] Therefore, an object of the present disclosure is to make it possible to hold an imaging plate in a normal position. [Means for solving the problem]

[0006] In order to solve the above-mentioned problems, a radiation image reading device is a radiation image reading device that reads a radiation image from an imaging plate, and includes: a stage that holds the imaging plate; an excitation light source that irradiates the imaging plate held on the stage with excitation light; and a photodetector that detects emission light from the imaging plate in response to the excitation light, wherein the stage includes: a stage body having a support surface that can come into surface contact with the back surface of the imaging plate; a first direction positioning mechanism that has a pair of first direction positioning members, at least one of the pair of first direction positioning members moving along a first direction as a first direction movable positioning member to sandwich the imaging plate on the support surface along the first direction; and a second direction positioning mechanism that has a lower positioning member that supports the imaging plate on the support surface from below in a second direction that intersects with the first direction and is closer to the direction of gravity than the first direction, and the lower positioning member moves along the second direction relative to the stage body. [Effects of the Invention]

[0007] According to this radiation image reading device, the imaging plate can be held in the correct position. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a schematic perspective view showing a reading device according to an embodiment. [Figure 2] FIG. 2 is a partially exploded perspective view showing the reading device. [Figure 3] FIG. 3 is a view of the stage seen from the front side. [Figure 4] Figure 4 shows the stage as seen from the back. [Figure 5] FIG. 5 is a partial cross-sectional view taken along line VV in FIG. [Figure 6] FIG. 6 is a diagram for explaining the operation of the positioning unit operating mechanism. [Figure 7] FIG. 7 is a diagram for explaining the operation of the positioning unit operating mechanism. [Figure 8]FIG. 8 is a diagram for explaining the operation of the positioning unit operating mechanism. [Figure 9] FIG. 9 is a diagram for explaining the operation of the positioning unit operating mechanism. [Figure 10] FIG. 10 is a diagram for explaining the operation of the positioning unit operating mechanism. [Figure 11] FIG. 11 is a diagram for explaining the tilt correction operation of the imaging plate. [Figure 12] FIG. 12 is a diagram for explaining the tilt correction operation of the imaging plate. [Figure 13] FIG. 13 is a diagram for explaining the operation of the positioning unit operating mechanism according to the modified example. [Figure 14] FIG. 14 is a diagram for explaining the operation of the positioning unit operating mechanism according to the modified example. [Figure 15] FIG. 15 is a diagram for explaining the operation of the positioning unit operating mechanism according to the modified example. [Figure 16] FIG. 16 is a diagram for explaining the operation of the positioning unit operating mechanism according to the modified example. [Figure 17] FIG. 17 is a diagram for explaining an operating surface and a cam surface according to another modified example. DETAILED DESCRIPTION OF THE INVENTION

[0009] {Embodiment} <Overall structure> A radiation image reading device according to an embodiment will now be described. Fig. 1 is a schematic perspective view of a reading device 20. In Fig. 1, a housing 30 is indicated by a two-dot chain line. Fig. 2 is a partially exploded perspective view of the reading device 20.

[0010] The radiation image reading device 20 is a device that reads a radiation image from the surface 10 a of the imaging plate 10 .

[0011] The imaging plate 10 has a flat shape and a radiation image-forming layer 11, and is a storage medium for storing radiation images. The radiation image-forming layer 11 is exposed on the surface 10a of the imaging plate 10. The radiation image-forming layer 11 accumulates the energy of irradiated radiation and emits light corresponding to the accumulated energy. For example, the radiation image-forming layer 11 may be formed by coating one major surface of a resin film with a stimulable phosphor. When X-rays from an X-ray generator penetrate an object to be photographed and irradiate the imaging plate 10, energy corresponding to the intensity of the X-rays accumulates in the radiation image-forming layer 11. The intensity of the X-rays is based on the distribution of X-ray absorption regions in the object to be photographed, and the distribution of energy accumulated in the radiation image-forming layer 11 represents a radiation image of the object photographed by X-rays. In this way, the imaging plate 10 stores the radiation image generated by X-rays as a latent image.

[0012] The reader 20 reads the radiation image from the radiation image forming layer 11 and generates image data of the radiation image. The reader 20 includes a stage 60, an excitation light source 92, a photodetector 94, and a setting guide 200. The stage 60 supports the imaging plate 10 from the rear surface 10b side. The excitation light source 92 irradiates the imaging plate 10 supported on the stage 60 with excitation light. The irradiation of the imaging plate 10 with excitation light causes the radiation image forming layer 11 of the imaging plate 10 to emit light. The emitted light is detected by the photodetector 94. Image data of the radiation image is generated based on the detection signal from the photodetector 94.

[0013] The setting guide 200 is a guide that guides the imaging plate 10, which is supplied from outside the reading device 20, toward the stage 60. By supplying the imaging plate 10 to the setting guide 200, the user of the reading device 20 can set the imaging plate 10 on the stage 60 in a position suitable for reading.

[0014] The front surface 10a of the imaging plate 10, on which the radiation image forming layer 11 is formed, may be considered to be the radiation image forming surface or the excitation light irradiated surface. The back surface 10b, which is opposite the front surface, may be considered to be the contact surface that faces the support surface 64F of the stage 60 and comes into contact with the support surface 64F. The back surface 10b is the surface opposite the surface that is irradiated with the excitation light and the surface opposite the radiation image forming layer 11. When the imaging plate 10 is correctly set on the stage 60, the surface of the imaging plate 10 that faces the same direction as the support surface 64F is the storage surface on which a latent image can be stored and the reading surface from which the stored latent image is read.

[0015] The configuration of each part of the reading device 20 will be described.

[0016] <About the case> The reading device 20 includes a housing 30 (see FIG. 1). Inside the housing 30, a stage 60, an excitation light source 92, and a photodetector 94 are housed.

[0017] The housing 30 has an insertion slot 31. The insertion slot 31 is formed, for example, on one of the peripheral side surfaces of the housing 30. The insertion slot 31 is formed, for example, in the shape of a slit that allows the imaging plate 10 to pass through. A user of the reading device 20 can insert the imaging plate 10 into the housing 30 through the insertion slot 31. A partial plate-like portion of the housing 30 in which the insertion slot 31 is formed may be detachable from the other portions of the housing 30. It is not necessary for the entire housing 30 to be formed as a single component. A portion may be detachable, or the housing 30 may be molded as an integral part.

[0018] A setting guide 200 may be provided on the inner side of the insertion port 31 of the housing 30. The setting guide 200 is a guide that guides the imaging plate 10 supplied through the insertion port 31 toward the stage 60. The setting guide 200 sets the imaging plate 10 on the stage 60 in a posture suitable for reading.

[0019] An outlet 32 ​​is provided in the lower part of the housing 30, for example, in the lower portion of one side of the housing 30. The outlet 32 ​​opens outward. A collection tray (not shown) is disposed inside the outlet 32. The imaging plates 10 ejected from the stage 60 are ejected onto the collection tray. A user of the reading device 20 can collect the imaging plates 10 ejected onto the collection tray through the outlet. The collection tray may be removable from the housing 30. If the collection tray is removable, it is preferable because it is easier to clean the collection tray.

[0020] Switches (not shown) for receiving various instructions may be provided on the housing 30. The switches are, for example, a power switch, a start switch for issuing an instruction to start reading, and the like.

[0021] A display device (not shown) may be provided in the housing 30. The display device may be configured, for example, with a liquid crystal display panel or an organic EL (electroluminescence) display panel. The read radiation image may be displayed on the display device. Various information for operation may be displayed on the display device. The display device may display information related to reading, for example, information related to the reading progress, such as the time remaining until the end of reading after the start of reading. The display device may display warnings, cautions, or error information regarding erroneous operation of the reading device 20. The display device may be a touch panel having a display function and a touch detection function. In this case, at least some of the functions of the above switches may be incorporated into the touch panel. The display device may be omitted.

[0022] It is not essential that the image data of the radiation image generated by reading the imaging plate is displayed on the display device. The image data of the radiation image may be transmitted to another computer that can communicate with the reading device 20 by wireless or wired communication. The image data of the radiation image may be recorded on a data recording medium (e.g., a flash memory) that is detachable from the reading device 20.

[0023] <About the internal structure of the case> The configuration of each part provided inside the housing 30 will be described.

[0024] A support member 40 is supported in a fixed position inside the housing 30. This support member 40 supports the stage 60, excitation light source 92, and photodetector 94. Note that the following example is merely an example, and the configuration for supporting the stage and setting guide is not limited to the following configuration. The configuration related to the support member does not limit the present disclosure, and the present disclosure is applicable to various configurations that use gravity to guide the imaging plate 10 to the stage.

[0025] <About the support member> 1 and 2, the support member 40 includes a support frame 44 in the shape of an elongated rectangular frame. The support frame 44 is supported at a fixed position and in a fixed posture within the housing 30 by a plate-shaped or elongated base support member. In this embodiment, the support frame 44 is supported in an oblique posture.

[0026] The support frame 44 includes a pair of longitudinal side plates 45 and a pair of lateral side plates 46. Each of the pair of longitudinal side plates 45 is formed as a rectangular plate that is long in one direction. Each of the lateral side plates 46 is formed as a square plate. The pair of longitudinal side plates 45 are positioned parallel to each other. Two edges on one side of the pair of longitudinal side plates 45 are connected by one lateral side plate 46, and two edges on the other side of the pair of longitudinal side plates 45 are connected by the other lateral side plate 46. As a result, the support frame 44 has a long rectangular frame shape that extends along the extension direction of the pair of longitudinal side plates 45. The longitudinal direction of the support frame 44 is the longitudinal direction of the longitudinal side plates 45. The support frame 44 is supported within the housing 30 with the longitudinal direction of the support frame 44 inclined with respect to the direction of gravity and the horizontal direction perpendicular to the direction of gravity. Hereinafter, the upper one of the pair of short-side side plates 46 may be referred to as short-side side plate 46H, and the lower one as short-side side plate 46L.

[0027] The support frame 44 has an opening facing diagonally upward. The opening is a rectangle surrounded by the long-side edges of a pair of longitudinal side plates 45 and the upper edges of a pair of lateral side plates 46. The stage 60, an excitation light source 92, and a photodetector 94 are supported in the opening. More specifically, the excitation light source 92 and the photodetector 94 are attached to the long-side edges of the pair of longitudinal side plates 45. The excitation light source 92 and the photodetector 94 are located between the pair of lateral side plates 46 and closer to the lower lateral side plate 46L. The excitation light source 92 irradiates excitation light toward the support frame 44, and the photodetector 94 detects light from the support frame 44.

[0028] The stage 60 is supported between a pair of longitudinal side plates 45 so as to be movable inside the excitation light source 92 and the photodetector 94. In the following description, for convenience, the side of the stage 60 on which the excitation light source 92 and the photodetector 94 are provided may be referred to as the front or front side, and the opposite side may be referred to as the rear or back side. Also, in the following description, the relative movement direction of the stage 60 with respect to the excitation light source 92 and the photodetector 94 may be referred to as the main scanning direction A1. When the imaging plate 10 held by the stage 60 passes inside the excitation light source 92 and the photodetector 94, excitation light from the excitation light source 92 is irradiated onto the imaging plate 10, and light emitted from the imaging plate 10 due to the excitation light is detected by the photodetector 94.

[0029] The stage 60 can be moved to a position where it extends downward beyond the lower short-side side plate 46L in the longitudinal direction of the support frame 44. When the stage 60 has been moved to a position where it extends downward beyond the short-side side plate 46L, a setting guide 200 is provided between the stage 60 and the insertion port 31. A user can set the imaging plate 10 on the stage 60 through the setting guide 200.

[0030] An outlet 32 ​​is located below the support frame 44. A collection tray, for example, is provided inside the outlet 32. When the stage 60 has moved to a position where it extends below the short-side side plate 46L, the imaging plate 10 ejected from the stage 60 falls into the collection tray. The imaging plate 10 on the collection tray is then removed to the outside of the housing 30 through the outlet 32.

[0031] Hereinafter, the position at which the imaging plate 10 can be set on the stage 60 may be referred to as the set position P1, the position at which the excitation light source 92 and the photodetector 94 read the radiation image of the imaging plate 10 on the stage 60 may be referred to as the read position P2, and the position at which the imaging plate 10 on the stage 60 is ejected may be referred to as the eject position P3. Also, the position at which the stage 60 passes the reading unit 90 may be referred to as the rear position P4. Figure 1 shows the positions of the bottom end of the stage 60 at positions P1, P2, P3, and P4. Figures 1 and 2 show the state in which the stage 60 is located at the eject position P3.

[0032] <Excitation light source and photodetector> The excitation light source 92 irradiates the imaging plate 10 held by the stage 60 with excitation light. The excitation light is light for exciting the radiation image forming layer 11, and is, for example, laser light of a specific wavelength that excites the radiation image forming layer 11. When the excitation light is irradiated onto the radiation image forming layer 11, the radiation image forming layer 11 emits light in accordance with the distribution of energy stored in the radiation image forming layer 11.

[0033] The excitation light source 92 may include a laser light source that emits laser light as excitation light and a MEMS (Micro Electro Mechanical Systems) mirror. For example, the laser light source may be reflected by the MEMS mirror so that the laser light is directed toward the surface 10a of the radiation image forming layer 11 in a sub-scanning direction A2 that intersects (is perpendicular to) the main scanning direction A1. Note that the mirror may be configured using a galvanometer mirror or a polygon mirror instead of the MEMS (Micro Electro Mechanical Systems) mirror. Depending on the mirror configuration, a separate lens system may be required, but an appropriate combination of these may be used in the reading device.

[0034] The photodetector 94 is a sensor that detects light emitted from the imaging plate 10 by the excitation light and outputs a signal according to the intensity of the light. Image data of the radiation image is generated based on the signal from this photodetector 94.

[0035] The photodetector 94 may have a configuration in which light-detecting elements are arranged in a row. For example, the photodetector 94 may be arranged in a position in which the arrangement direction of the elements is parallel to the sub-scanning direction A2. The light-detecting elements may be silicon photomultiplier tubes, photomultiplier tubes, photodiodes, etc.

[0036] In this embodiment, the excitation light source 92 and the photodetector 94 are integrated as a reading unit 90. For example, the excitation light source 92 and the photodetector 94 are integrated while being housed in a module case 91. A long and narrow reading slit is formed along the sub-scanning direction A2 in a portion of the module case 91 facing the support member 40. The excitation light passes through the reading slit and is irradiated toward the imaging plate 10. The emitted light from the imaging plate 10 passes through the reading slit and is detected by the photodetector 94.

[0037] While the stage 60 is moving in the main scanning direction A1, the laser light from the excitation light source 92 is incident on the surface of the radiation image forming layer 11 of the imaging plate 10 held on the stage 60, and the irradiation destination moves in the sub-scanning direction A2. As a result, the surface of the radiation image forming layer 11 (surface 10a of the imaging plate 10) emits light sequentially along a line in the sub-scanning direction A2.

[0038] The photodetector 94 is disposed at a position where it can detect the luminescent light of the radiation image forming layer 11 generated by the laser beam from the excitation light source 92. For example, the excitation light source 92 is disposed so as to irradiate the imaging plate 10 with laser beam from an oblique direction, and the photodetector 94 is disposed in front of the position where the laser beam irradiates the imaging plate 10. When the surface of the radiation image forming layer 11 (surface 10a of the imaging plate 10) sequentially emits luminescent light along a line in the sub-scanning direction A2, the luminescent light is detected by the photodetector 94.

[0039] While the stage 60 is moving, scanning by the excitation light source 92 and scanning by the photodetector 94 in the sub-scanning direction A2 are repeated, so that a radiation image of a wide surface of the imaging plate 10, for example, the entire surface of the imaging plate 10, is read by the photodetector 94.

[0040] It is not essential to perform reading while the stage 60 is moving. For example, the excitation light source 92 and the photodetector 94 may be configured to move while the stage 60 is stationary. Alternatively, the stage 60 and both the excitation light source 92 and the photodetector 94 may be configured to move.

[0041] <About the stage and its movement configuration> Fig. 3 is a view of the stage 60 as seen from the front side. Fig. 4 is a view of the stage 60 as seen from the back side. In Fig. 3, the support frame 44 is shown by a solid line, and in Fig. 4, the support frame 44 is shown by a two-dot chain line. Fig. 5 is a partial cross-sectional view taken along line VV in Fig. 3. In Fig. 5, the support frame 44 and the setting guide 200 are shown by a two-dot chain line.

[0042] 1 to 5, the stage 60 is configured to hold the imaging plate 10. For example, the stage 60 includes a plate-like portion that extends wider than the imaging plate 10. The imaging plate 10 is held at a fixed position and in a fixed orientation relative to the stage 60, in a state where the imaging plate 10 is in contact with a support surface 64F on one main surface side of the stage 60. The configuration in which the stage 60 holds the imaging plate 10 will be described in more detail later.

[0043] The stage 60 moves along the main scanning direction A1 while holding the imaging plate 10. Here, the configuration for movably supporting the stage 60 will be mainly described.

[0044] The stage 60 can move along the main scanning direction A1 between the edges of the long sides of the pair of longitudinal side plates 45. In the opening of the support frame 44 facing diagonally upward, the edge of the lower short-side side plate 46L is recessed more than the edges of the long sides of the pair of longitudinal side plates 45. Therefore, the stage 60 can move downward along the main scanning direction A1 from between the pair of longitudinal side plates 45 over the lower short-side side plate 46L. In other words, the stage 60 can move back and forth along the main scanning direction A1 between positions between the pair of longitudinal side plates 45 (positions P2 and P4 indicated by two-dot chain lines in FIG. 1) and positions P1 and P3 protruding downward between the pair of longitudinal side plates 45.

[0045] The stage 60 is configured so as to be movable by a stage movement mechanism 50. The stage movement mechanism 50 includes a movement drive unit 52 and a guide rod 56.

[0046] The movement driver 52 applies a driving force to the stage 60 along the main scanning direction A1. In this embodiment, the movement driver 52 includes a motor 53 and a screw shaft 54. The screw shaft 54 ​​is a rod-shaped member having a threaded periphery. The screw shaft 54 ​​is rotatably supported by the pair of short-side side plates 46 so as to span between them. The motor 53 is fixed to the support frame 44 so as not to rotate. For example, the motor 53 is fixed to the outer side of the lower short-side side plate 46L so as not to rotate. The shaft of the motor 53 is fixed to the screw shaft 54 ​​so as not to rotate relative to the screw shaft 54. The screw shaft 54 ​​is rotated in the forward or reverse direction in response to the rotation of the motor 53 in the forward or reverse direction. The rotational motion of the shaft of the motor 53 may be transmitted to the screw shaft 54 ​​via a transmission device such as a gear or a pulley.

[0047] The direction of movement by the movement driver 52 is not limited to the above example, and may be horizontal or the direction of gravity. The movement driver 52 may be any actuator that moves the stage 60, and may be a linear motor or the like in addition to the above configuration. Alternatively, it may be a mechanism that moves using a belt. Instead of moving the stage, the reading unit 90 may be moved to read the imaging plate on the stage. If the reading unit is a sensor that can read the planar information of the imaging plate, it is also possible that both the stage and the reading unit do not move.

[0048] The stage 60 has a through-hole 62h1 with a screw groove (see FIG. 1). The screw shaft portion 54 is screwed into the through-hole 62h1. By rotating the screw shaft portion 54, the stage 60, into which the screw shaft portion 54 is screwed, is driven to move along the main scanning direction A1.

[0049] The guide rod 56 is a long, thin rod-shaped member that is fixed to the pair of short-side side plates 46 so as to span between them. The guide rod 56 passes through a guide groove 62h2 formed in the stage 60 (see FIGS. 1 and 2). This allows the guide rod 56 to function as a restraint against the stage 60 rotating around the screw shaft portion 54. Here, one guide rod 56 is provided, but multiple guide rods 56 may be provided.

[0050] The stage 60 is moved back and forth by the stage moving mechanism 50 between a set position P1 and a reading position P2.

[0051] The set position P1 is a position where the imaging plate 10 can be set on the stage 60. In this embodiment, the set position P1 is set to a position that protrudes outward (downward) from the lower short-side side plate 46L. At the set position P1, the longitudinal middle portion and the lower end portion of the stage 60 extend downward from the lower short-side side plate 46L, and the portion of the stage 60 near the upper end is positioned between the pair of longitudinal sides above the short-side side plate 46L.

[0052] In this state, the support surface 64F of the stage 60 is inclined with respect to the direction of gravity. Here, the support surface 64F is inclined in the same inclination direction as the extension direction of the longitudinal side plate 45. In other words, the support surface 64F is inclined so as to face obliquely upward.

[0053] The stage 60 positioned at the setting position P1 can receive the imaging plate 10 guided by the setting guide 200. That is, the setting guide 200 is located between the stage 60 positioned at the setting position P1 and the insertion slot 31 (see FIGS. 1 and 5). The setting guide 200 has a guide surface 202 that extends obliquely downward from the insertion slot 31 toward a lower position on the support surface 64F. When the imaging plate 10 is inserted into the insertion slot 31 from outside the reading device 20, the imaging plate 10 moves downward under its own weight while being guided by the guide surface 202. When the lower edge of the imaging plate 10 reaches the support surface 64F, the lower edge of the imaging plate 10 slides obliquely downward in accordance with the inclination of the support surface 64F, and the imaging plate 10 tilts toward the support surface 64F. As a result, the imaging plate 10 (rear surface 10b) is positioned and held by a positioning mechanism (described later) while in surface contact with the support surface 64F. In this manner, this embodiment is configured to utilize gravity when guiding the imaging plate 10 to the stage 60 .

[0054] It is not essential that the setting position P1 be set at the above position, and for example, it may be set between a pair of longitudinal side plates 45 depending on the positional relationship with the setting guide 200.

[0055] As described above, the reading position P2 is the position where the excitation light source 92 and the photodetector 94 read a radiation image, i.e., the position where the photodetector 94 reads a radiation image on the imaging plate 10 in response to the excitation light from the excitation light source 92. In this embodiment, the reading position P2 is set at a position between the pair of longitudinal side plates 45. More specifically, the reading position P2 is set at a lower position between the pair of longitudinal side plates 45.

[0056] That is, the reading unit 90, which includes an excitation light source 92 and a photodetector 94, is fixed between the edge portions on the long sides of a pair of longitudinal side plates 45 by screws or the like. The reading unit 90 is located between the pair of longitudinal side plates 45 and near the set position P1. A reading slit (not shown) is formed on the surface of the reading unit 90 facing the inside of the support frame 44. Excitation light from the excitation light source 92 in the reading unit 90 passes through the reading slit and is irradiated onto the imaging plate 10 on the stage 60. Furthermore, emitted light from the imaging plate 10, excited by this excitation light, passes through the reading slit and enters the photodetector 94.

[0057] When the imaging plate 10 is set on the stage 60 at the set position P1, the stage 60 moves in the main scanning direction A1 toward the inside of the support frame 44. When the imaging plate 10 set on the stage 60 reaches a position facing the reading slit of the reading unit 90, the reading unit 90 starts reading the radiation image of the imaging plate 10. As the stage 60 moves, the reading unit 90 sequentially reads the radiation image of the imaging plate 10. When the imaging plate 10 passes the reading slit, the reading by the reading unit 90 ends. When the radiation image is read by moving the stage 60, as in this embodiment, the reading position P2 may be understood to be the position where the imaging plate 10 on the stage 60 (if multiple sizes of imaging plates 10 are expected, the imaging plate 10 with the widest installation area (see the area in FIG. 3 where both the tallest and widest imaging plates 10 can be installed)) reaches the reading slit and reading starts.

[0058] Unlike the above example, it is also possible to imagine a case where the reading unit 90 moves in the main scanning direction A1 relative to the imaging plate 10 that is stationary at a fixed position to read a radiation image, or a case where a three-dimensional sensor reads a radiation image relative to the imaging plate 10 that is stationary at a fixed position. In this case, the position where the imaging plate 10 that is stationary at a fixed position is held is the reading position P2.

[0059] In this embodiment, the stage 60 is also moved to an ejection position P3 by the stage movement mechanism 50 (FIGS. 1 and 2). The ejection position P3 is a position for ejecting the imaging plate 10 set on the stage 60. The ejection position P3 is set at a position farther away from the reading position P2 than the set position P1. This example is not limiting, and the imaging plate 10 on the stage 60 may be ejected by a separate mechanism at a position different from the ejection position P3, for example, at the set position P1.

[0060] As already mentioned, a collection tray is provided, for example, below the discharge position P3. The imaging plate 10 can slide down on the stage 60 at the discharge position P3 and be discharged into the collection tray.

[0061] In this embodiment, the stage 60 is also moved to a rear position P4 by the stage movement mechanism 50 (see FIG. 1). The rear position P4 is located on the opposite side of the set position P1 with respect to the reading position P2. That is, the stage 60 can move from the set position P1 to the rear position P4 via the reading position P2. At the rear position P4, the imaging plate 10 on the stage 60 may be exposed and not covered by the reading unit 90, or may be covered by another member.

[0062] The operation of the stage moving mechanism 50 is controlled by a control unit 100 (see FIG. 1). The control unit 100 is configured, for example, by a computer including at least one processor and a storage unit. The processor is a CPU (Central Processing Unit) or the like, and is configured by an electric circuit. The processor executes a reading program to realize various functions for reading. The control unit 100 controls the direction and amount of rotation of the motor 53, thereby controlling the movement of the stage 60 along the main scanning direction A1.

[0063] The control unit 100 also controls the excitation light source 92 and the photodetector 94 of the reading unit 90. The control unit 100 may also perform various signal processing, image processing, and display processing by a display device to generate a radiographic image based on the signal detected by the photodetector 94.

[0064] <Overall Stage Composition> The following describes the overall configuration of the stage 60. As shown in Figures 1 to 5, the stage 60 includes a stage main body 61, a first direction positioning mechanism 70, and a second direction positioning mechanism 71.

[0065] The stage main body 61 has a support surface 64F that can come into surface contact with the rear surface 10b of the imaging plate 10. In this embodiment, the stage main body 61 includes a movable support body 62 and a plate-shaped portion 64.

[0066] The movable support 62 is formed in a rectangular parallelepiped shape. A through hole 62h1 is formed in the movable support 62 (see FIG. 1). As already described, the screw shaft portion 54, which can be rotated in both forward and reverse directions by the motor 53, is screwed into the through hole 62h1. When the screw shaft portion 54 rotates in the forward direction, the stage 60 moves to one side along the screw shaft portion 54, and when the screw shaft portion 54 rotates in the reverse direction, the stage 60 moves to the other side along the screw shaft portion 54. Such a structure is, for example, a structure called a ball screw.

[0067] A guide groove 62h2 parallel to the through hole 62h1 is formed in the movable support body 62 (see FIGS. 1 and 2). Therefore, the movable support body 62 is driven to move in both directions along the main scanning direction A1 in response to the forward or reverse rotation of the screw shaft portion 54 screwed into the through hole 62h1, while being guided by the guide rod 56 inserted into the guide groove 62h2.

[0068] A recess 63 is formed in the base end of the movable support 62 on the side fixed to the plate-shaped portion 64. The recess 63 is recessed in the widthwise center of the movable support 62 and penetrates along the movement direction (main scanning direction A1) of the stage 60. The recess 63 is a space for preventing the movable support 62 from contacting the cam plate 82 supported by the lower short-side side plate 46L.

[0069] The plate-like portion 64 is formed in a plate-like shape, here a rectangular plate-like shape, that is larger than the imaging plate 10. It is not essential that the plate-like portion 64 be formed in a rectangular plate-like shape, and it may be formed in another shape such as an ellipse.

[0070] A support surface 64F is provided on one side surface of the plate-shaped portion 64. The support surface 64F may extend wider than the imaging plate 10. When multiple sizes of imaging plates 10 are assumed, the support surface 64F may extend wider than the largest imaging plate 10.

[0071] More specifically, the plate-shaped portion 64 is formed in a rectangular shape that is long in one direction (here, the main scanning direction A1). Of the other surface of the plate-shaped portion 64 (the surface opposite to the support surface 64F), one portion in the longitudinal direction of the plate-shaped portion 64 is fixed to the movable support body 62. The fixing is performed, for example, by screwing. The plate-shaped portion 64 is supported in a cantilevered manner by the movable support body 62 so as to extend from the movable support body 62 toward the set position P1 along the main scanning direction A1. Of the one surface of the plate-shaped portion 64, a portion that extends flush between the middle of the main scanning direction A1 and the middle of the sub-scanning direction A2 is the support surface 64F that can come into surface contact with the back surface 10b of the imaging plate 10. A portion of the plate-shaped portion 64 around the support surface 64F may protrude beyond the support surface 64F.

[0072] When the stage 60 is supported by the support member 40, the plate-shaped portion 64 and the support surface 64F are inclined with respect to the direction of gravity (downward), and the support surface 64F faces diagonally upward. In this embodiment, the inclination angle of the plate-shaped portion 64 and the support surface 64F matches the inclination angle of the longitudinal side plate 45 in the extension direction. The plate-shaped portion 64 and the support surface 64F move along the main scanning direction A1 under the guidance of the guide rod 56 while maintaining a constant inclination angle. When the movable support 62 moves toward the lower short-side side plate 46L, the portion of the plate-shaped portion 64 extending from the movable support 62 passes over the lower short-side side plate 46L and extends diagonally downward. In this state, because the support surface 64F is inclined so as to face diagonally upward, the imaging plate 10 supplied onto the imaging plate 10 through the setting guide 200 can be received on the support surface 64F.

[0073] The support surface 64F does not have to be inclined with respect to the direction of gravity. For example, the support surface 64F may be aligned along a horizontal direction perpendicular to the direction of gravity, or along the direction of gravity.

[0074] <Regarding the positioning mechanism> The positioning mechanism will be described in more detail. The stage 60 is equipped with a first direction positioning mechanism 70 and a second direction positioning mechanism 71 as positioning mechanisms. The positioning mechanisms position the imaging plate 10 in a correct orientation on the support surface 64F. The correct orientation refers to a position and tilt state of the imaging plate 10 that is set in advance with respect to the stage 60, and is a predetermined position and tilt suitable for reading by the reading unit 90.

[0075] The first direction positioning mechanism 70 positions the imaging plate 10 in the first direction F1, and the second direction positioning mechanism 71 positions the imaging plate 10 in the second direction F2.

[0076] For ease of explanation, the first direction F1 and the second direction F2 will be described below. The first direction F1 is a direction along the support surface 64F. The second direction F2 is a direction along the support surface 64F that intersects with the first direction F1 and is closer to the direction of gravity than the first direction F1. In other words, the first direction F1 and the second direction F2 intersect with each other on a plane horizontal to the support surface 64F, and the second direction F2 is closer to the direction of gravity than the first direction F1. In this embodiment, the first direction F1 is a direction along a horizontal direction perpendicular to the direction of gravity. Therefore, the first direction F1 coincides with the sub-scanning direction A2. Furthermore, in this embodiment, the second direction F2 is a direction along the support surface 64F and perpendicular to the sub-scanning direction A2. Therefore, the second direction F2 coincides with the main scanning direction A1. Gravity can act in the second direction F2. The first direction F1 may be a direction different from the sub-scanning direction A2. The second direction F2 may be a direction different from the main scanning direction A1.

[0077] The first direction positioning mechanism 70 has a pair of first direction positioning units 72A, 72B. When at least one of the pair of first direction positioning units 72A, 72B moves as a first direction movable positioning unit, the pair of first direction positioning units 72A, 72B of the first direction positioning mechanism 70 sandwich the imaging plate 10 on the support surface 64F along the first direction F1.

[0078] In this embodiment, the first direction positioning portion 72B is a first direction movable positioning portion that moves along the first direction F1 relative to the plate-shaped portion 64. The first direction positioning portion 72A is a first direction fixed positioning portion that is fixed at a certain position relative to the plate-shaped portion 64. The movable first direction positioning portion 72B moves toward and away from the fixed first direction positioning portion 72A along the first direction F1. As a result, the imaging plate 10 on the support surface 64F is sandwiched between the first direction positioning portions 72A and 72B along the first direction F1. At this time, one side edge of the imaging plate 10 is pressed against the fixed first direction positioning portion 72A, thereby more accurately positioning the imaging plate 10 in the first direction F1.

[0079] It is not essential that one of the pair of first direction positioning units moves along the first direction and the other does not move along the first direction F1. Both of the pair of first direction positioning units may move along the first direction F1 to sandwich the imaging plate 10.

[0080] The second direction positioning mechanism 71 has a lower positioning portion 72C. The lower positioning portion 72C supports the imaging plate 10 on the support surface 64F from below in the second direction F2, in which gravity acts. In other words, the second direction F2 is closer to the direction of gravity than the first direction F1. Therefore, gravity due to the weight of the imaging plate 10 acts downward in the second direction F2 along the support surface 64F. This causes the imaging plate 10 to slide downward in the second direction F2 along the support surface 64F. The lower positioning portion 72C contacts the imaging plate 10 from below and supports the imaging plate 10 on the support surface 64F.

[0081] The lower positioning portion 72C is movable along the second direction F2 relative to the plate-shaped portion 64. When the lower positioning portion 72C moves along the second direction F2, the imaging plate 10 supported from below by the lower positioning portion 72C can move along the second direction F2. In particular, when the lower positioning portion 72C moves upward along the second direction F2, the imaging plate 10 supported from below by the lower positioning portion 72C is forcibly moved upward along the second direction F2.

[0082] In this embodiment, the second direction positioning mechanism 71 has an upper positioning part 72D. The upper positioning part 72D is fixed to the plate-shaped part 64 at a position spaced upward in the second direction F2 from the lower positioning part 72C. As a result, the upper positioning part 72D faces the lower positioning part 72C in the second direction F2. The lower positioning part 72C moves toward and away from the upper positioning part 72D in the second direction F2.

[0083] As described above, with the imaging plate 10 supported on the support surface 64F, the lower edge of the imaging plate 10 is supported by the lower positioning portion 72C. When the lower positioning portion 72C moves upward in this state, the imaging plate 10 moves upward on the support surface 64F in the second direction F2. Then, the upper edge of the imaging plate 10 comes into contact with the upper positioning portion 72D, restricting its upward movement. As a result, with the pair of first-direction positioning portions 72A, 72B sandwiching the imaging plate 10 in the first direction F1, the upper positioning portion 72D and the lower positioning portion 72C sandwich the imaging plate 10 in the second direction F2. At this time, because the upper positioning portion 72D is fixed at a fixed position relative to the plate-shaped portion 64, the upper edge of the imaging plate 10 is accurately positioned at a fixed position relative to the plate-shaped portion 64.

[0084] It is not essential that the upper positioning portion 72D be fixed at a fixed position relative to the plate-shaped portion 64. The upper positioning portion may move along the second direction F2 relative to the plate-shaped portion 64, and the imaging plate may be sandwiched between the lower positioning portion and the upper positioning portion that have moved closer to each other.

[0085] In this embodiment, the first direction positioning portions 72A and 72B are configured to position the device in the horizontal direction, and the lower positioning portion 72C and the upper positioning portion 72D are configured to position the device in the vertical direction. The lower positioning portion 72C and the upper positioning portion 72D may be understood as second direction positioning portions.

[0086] The imaging plate 10 moves to the reading position P2 while being held in the correct position by the first direction positioning mechanism 70 and the second direction positioning mechanism 71. At the reading position P2, the reading unit 90 reads the radiation image of the imaging plate 10 held in the correct position on the stage 60.

[0087] In this embodiment, the stage 60 supports the imaging plate 10 in a position where the longitudinal direction of the imaging plate 10 is inclined with respect to the horizontal direction. Specifically, the longitudinal directions of the plate-shaped portion 64 and the support surface 64F on one side of the plate-shaped portion 64 are inclined with respect to the horizontal direction, and the lateral direction is aligned with the horizontal direction. Therefore, when the imaging plate 10 is supported on the stage 60 in a position where the longitudinal direction of the imaging plate 10 is aligned with the longitudinal directions of the plate-shaped portion 64 and the support surface 64F, the longitudinal direction of the imaging plate 10 is inclined with respect to the horizontal direction.

[0088] In this embodiment, the pair of first-direction positioning portions 72A, 72B are spaced apart more narrowly than the lower positioning portion 72C and the upper positioning portion 72D. In other words, the maximum distance between the pair of first-direction positioning portions 72A, 72B is smaller than the maximum distance between the lower positioning portion 72C and the upper positioning portion 72D. This makes it easy to set the imaging plate 10 on the stage 60 in a position aligned with the second direction F2. In particular, if the maximum distance between the pair of first-direction positioning portions 72A, 72B is smaller than the smallest dimension among the longitudinal dimensions of the imaging plates 10 of various sizes, it is difficult to position the imaging plate 10 with its longitudinal direction aligned with the first direction F1. This makes it difficult to set the imaging plate 10 on the stage 60 with its length and width incorrect.

[0089] Regardless of this embodiment, the stage may support the imaging plate in a position in which the short-side direction of the imaging plate is inclined with respect to the horizontal direction. For example, the long-side direction of the plate-like portion and the support surface of the stage may be aligned with the horizontal direction, and the short-side direction may be inclined with respect to the horizontal direction.

[0090] When the imaging plate 10 is positioned at the set position P1, the pair of first direction positioning portions 72A, 72B are in an open state. The lower positioning portion 72C and the upper positioning portion 72D are also in an open state (see FIG. 3). In this state, the imaging plate 10 can be set on the support surface 64F of the stage 60.

[0091] When the imaging plate 10 is located at the reading position P2, the pair of first direction positioning units 72A, 72B are in close proximity to each other. Here, the movable first direction positioning unit 72B is in close proximity to the fixed first direction positioning unit 72A. The edge of the imaging plate 10 on the movable side of the first direction positioning unit 72B comes into contact with the first direction positioning unit 72B, and the imaging plate 10 is pushed toward the fixed first direction positioning unit 72A. Then, the edge of the imaging plate 10 on the first direction positioning unit 72A comes into contact with the fixed first direction positioning unit 72A. This positions the imaging plate 10 in the first direction F1.

[0092] Furthermore, when the imaging plate 10 is positioned at the reading position P2, the lower positioning portion 72C and the upper positioning portion 72D are in close proximity to each other. Here, the movable lower positioning portion 72C is in close proximity to the fixed upper positioning portion 72D. The lower edge of the imaging plate 10 comes into contact with the movable lower positioning portion 72C, and the imaging plate 10 is pushed toward the upper positioning portion 72D. Then, the upper edge of the imaging plate 10 comes into contact with the upper positioning portion 72D. This positions the imaging plate 10 in the second direction F2.

[0093] In this embodiment, the fixed-side first-direction positioning part 72A and upper positioning part 72D are arranged at fixed positions on the support surface 64F of the stage 60. The normal posture is when one edge of the imaging plate 10 contacts the first-direction positioning part 72A and the upper edge of the imaging plate 10 contacts the upper positioning part 72D.

[0094] <First direction positioning mechanism> The first direction positioning mechanism 70 will now be described in more detail.

[0095] The first direction positioning portion 72A is a long, narrow portion extending along one side of the plate-shaped portion 64 in the horizontal direction. In this embodiment, the long, first direction positioning portion 72A, which is separate from the plate-shaped portion 64, is fixed to one side of the plate-shaped portion 64 by screws or the like. The first direction positioning portion 72A protrudes beyond the support surface 64F. The length of the first direction positioning portion 72A may be longer or shorter than the vertical dimension (the maximum vertical dimension when multiple sizes are assumed) of the imaging plate 10 supported on the support surface 64F.

[0096] The surface of the first direction positioning portion 72A facing the first direction positioning portion 72B is a positioning surface 72Af that contacts the edge of the imaging plate 10 to position the imaging plate 10.

[0097] In this embodiment, the first direction positioning portion 72A is formed from a separate member from the plate-shaped portion 64, but the first direction positioning portion may also be a part that is integrally formed with the plate-shaped portion 64 by cutting processing or the like.

[0098] The first direction positioning portion 72B is provided at a distance from the first direction positioning portion 72A in the first direction F1.

[0099] More specifically, slits 65a and 65b are formed along the first direction F1 in a portion of the plate-shaped portion 64 opposite the first-direction positioning portion 72A. In this embodiment, the two slits 65a and 65b are formed parallel to each other at different positions in the second direction F2. The two slits 65a and 65b open outward along the first direction F1. A recess 65g recessed below the support surface 64F is formed at an outer (upper) edge of one (upper) slit 65b in the second direction F2. An elongated guide portion 65c extending along the first direction F1 protrudes from an intermediate portion of the other (lower) slit 65a in the second direction F2. The guide portion 65c is recessed below the support surface 64F.

[0100] The first-direction positioning portion 72B is separate from the plate-shaped portion 64 and is supported by the slits 65a and 65b so as to be movable along the first direction F1. More specifically, a portion of the first-direction positioning portion 72B is formed into a shape that can be positioned within the slits 65a and 65b, and another portion of the first-direction positioning portion 72B is positioned so as to protrude beyond the support surface 64F. Even more specifically, the first-direction positioning portion 72B includes positioning bodies 72Ba and 72Bb and a back support body 72Bc. The positioning body 72Ba is a plate-shaped portion that is positioned closer to the support surface 64F than the guide portion 65c with respect to the slit 65a. A portion of the positioning body 72Ba in the thickness direction is positioned within the slit 65a so as to be movable along the slit 65a. The remaining portion of the positioning body 72Ba in the thickness direction protrudes from the slit 65a and protrudes beyond the support surface 64F. The positioning body 72Bb is a plate-shaped portion that is positioned closer to the support surface 64F than the recess 65g with respect to the slit 65b. A part of the positioning body 72Bb in the thickness direction is arranged within the slit 65b so as to be movable along the slit 65b, and the remaining part of the positioning body 72Bb in the thickness direction protrudes from the slit 65b and protrudes beyond the support surface 64F.

[0101] The back-side support 72Bc is a portion that continues from the positioning bodies 72Ba and 72Bb on the side opposite to the support surface 64F. The back-side support 72Bc contacts the portion of the plate-shaped portion 64 between the slits 65a and 65b from the side opposite to the support surface 64F. The positioning bodies 72Ba and 72Bb contact the bottom surface of the recess 65g and the guide portion 65c from the support surface 64F side, and the back-side support 72Bc contacts the plate-shaped portion 64 from the side opposite to the support surface 64F, so that the first-direction positioning portion 72B can move along the slits 65a and 65b while being positioned in the thickness direction of the plate-shaped portion 64.

[0102] The first-direction positioning unit 72B has positioning surfaces 72Baf and 72Bbf as multiple first-direction movable positioning surfaces that contact the imaging plate 10 at spaced positions in the second direction F2. In this embodiment, the surface of the positioning body 72Ba that faces the first-direction positioning unit 72A is the positioning surface 72Baf, and the surface of the positioning body 72Bb that faces the first-direction positioning unit 72A is the positioning surface 72Bbf. The positioning surface 72Bbf is located on an extension of the positioning surface 72Baf in the second direction F2. A gap corresponding to the spacing between the slits 65a and 65b exists between the positioning surfaces 72Baf and 72Bbf.

[0103] The first-direction movable positioning member may have one positioning surface that is continuous in the second direction, similar to the first-direction positioning member 72A. The first-direction fixed positioning member may have multiple positioning surfaces that are spaced apart in the second direction, similar to the first-direction positioning member 72B.

[0104] The first direction positioning unit 72B is movable between a distant position (see FIG. 3) away from the first direction positioning unit 72A and a close position (see FIGS. 7 to 9) closer to the first direction positioning unit 72A than the distant position. When the stage 60 is located at the set position P1, the first direction positioning unit 72B is located at the distant position. When the stage 60 is located at the reading position P2, the first direction positioning unit 72B is movable to the close position.

[0105] In this embodiment, the imaging plate 10 is set on the stage 60 with the longitudinal direction of the imaging plate 10 aligned with the main scanning direction A1. Therefore, the width of the imaging plate 10 is the width in the lateral direction of the imaging plate 10.

[0106] When the first direction positioning unit 72B is located at the separated position, the distance between the first direction positioning unit 72A and the first direction positioning unit 72B is set to be larger than the width of the imaging plate 10. When imaging plates 10 of multiple sizes are selectively set on the stage 60, the distance is set to be larger than the largest width of the imaging plates 10 of the multiple sizes.

[0107] When the first direction positioning unit 72B is located at the closest position to the first direction positioning unit 72A, the distance between the first direction positioning unit 72A and the first direction positioning unit 72B is set to be smaller than the width of the imaging plate 10. When imaging plates 10 of multiple sizes are selectively set on the stage 60, the distance is set to be smaller than the smallest width of the imaging plates 10 of the multiple sizes.

[0108] Therefore, with the first direction positioning part 72B located at the separated position, the imaging plate 10 can be disposed between the first direction positioning parts 72A and 72B. Furthermore, by moving the first direction positioning part 72B from the separated position to the close position, the imaging plate 10 can be sandwiched between the first direction positioning parts 72A and 72B.

[0109] More specifically, the imaging plate 10 is placed on the support surface 64F with the first direction positioning unit 72B located at the separated position, i.e., with the first direction positioning units 72A and 72B spaced apart (see FIGS. 3 and 6). In this state, the first direction positioning unit 72B moves toward the close position (first direction positioning unit 72A). Then, one edge of the imaging plate 10 is pressed inward by the first direction positioning unit 72B, causing the imaging plate 10 to slide along the support surface 64F toward the first direction positioning unit 72A. Then, the edge of the imaging plate 10 on the first direction positioning unit 72A side is pressed against the first direction positioning unit 72A, restricting movement toward the first direction positioning unit 72A side.

[0110] In other words, the support surface 64F has an area large enough to support imaging plates 10 of multiple sizes, and the stage 60 can support imaging plates 10 of multiple sizes. The first-direction positioning unit 72B moves between a position where the largest imaging plate 10 of the multiple sizes can be sandwiched between the pair of first-direction positioning units 72A, 72B and a position where the smallest imaging plate of the multiple sizes can be sandwiched between the pair of first-direction positioning units. Here, the movement range is even larger than the range of the first-direction positioning units 72A, 72B. This allows the pair of first-direction positioning units 72A, 72B to flexibly sandwich imaging plates 10 of multiple sizes.

[0111] When the imaging plate 10 is tilted, the edges (sides or corners) of the imaging plate 10 typically contact the positioning surfaces 72Af, 72Baf, and 72Bbf, correcting the edges of the long sides of the imaging plate 10 so that they are aligned with the positioning surfaces 72Af, 72Baf, and 72Bbf. However, the force that moves the first-direction positioning unit 72B toward the first-direction positioning unit 72A can also act as a force that presses the corners of the imaging plate 10 against the positioning surfaces 72Af, 72Baf, and 72Bbf. As a result, the corners of the imaging plate 10 may be pressed strongly against the positioning surfaces 72Af, 72Baf, and 72Bbf, preventing the imaging plate 10 from moving along the positioning surfaces 72Af, 72Baf, and 72Bbf in the second direction F2. In this case, the tilt of the imaging plate 10 may not be corrected.

[0112] In such a case, by moving the lower positioning portion 72C along the second direction F2, the corner of the imaging plate 10 is forcibly moved along the second direction F2 relative to the positioning surfaces 72Af, 72Baf, and 72Bbf. This allows the corner of the imaging plate 10 to move smoothly along the second direction F2 on the positioning surfaces 72Af, 72Baf, and 72Bbf, and is expected to successfully correct the tilt of the imaging plate 10. The tilt correction operation will be described in more detail later.

[0113] The corners of the imaging plate 10 are the portions where four linear sides of the periphery of the imaging plate 10 intersect, and in this embodiment, are rounded corners.

[0114] The stage 60 has a spring 72Bs as a biasing member that biases the first-direction positioning portion 72B toward the first-direction positioning portion 72A. For example, on the back surface side of the plate-shaped portion 64, one end of the spring 72Bs is fixed to the back-side support 72Bc, and the other end is fixed at a fixed position on the back surface of the plate-shaped portion 64. Between the back-side support 72Bc and the fixed position on the back surface of the plate-shaped portion 64, the spring 72Bs is always in an extended state, and the compression force of the spring 72Bs biases the first-direction positioning portion 72B toward the first-direction positioning portion 72A.

[0115] A roller 72Bq is integrally combined with the first direction positioning portion 72B as a receiving portion that receives a force that moves the first direction positioning portion 72B. In this embodiment, the roller 72Bq is rotatably supported by the back side support 72Bc. The rotation axis of the roller 72Bq is along a direction perpendicular to the first direction F1 and the second direction F2. The roller 72Bq protrudes from the plate-shaped portion 64 on the side opposite to the support surface 64F. When the stage 60 moves, the roller 72Bq comes into contact with a cam plate 82 fixed to the support frame 44, thereby moving the first direction positioning portion 72B.

[0116] The movement of the first direction positioning part 72B in association with the movement of the stage 60 will be described in further detail later.

[0117] <Second-direction positioning mechanism> The second direction positioning mechanism 71 will now be described in more detail.

[0118] The lower positioning portion 72C is a portion located on one side of the plate-shaped portion 64 in the second direction F2, in this case, the lower side.

[0119] More specifically, a slit 67 is formed in the lower portion of the plate-shaped portion 64 along the second direction F2.

[0120] The lower positioning portion 72C is formed in the shape of a long plate extending along the extension direction of the slit 67. The thickness of the lower positioning portion 72C is greater than the thickness of the plate-shaped portion 64. A middle portion of the lower positioning portion 72C in the thickness direction is disposed within the slit 67. Guide grooves 72Cg are formed on both sides of the lower positioning portion 72C (see FIG. 2). With both side edges of the slit 67 fitted into the guide grooves 72Cg, the lower positioning portion 72C is supported so as to be reciprocally movable along the direction along the slit 67 (second direction F2). When the imaging plate 10 is set, the lower positioning portion 72C can move along the slit 67 between a standby position Pw (see FIGS. 3, 6, and 7) where the imaging plate 10 is received at the lower edge thereof and a clamping position Ps (see FIGS. 8 and 9) that is above the standby position Pw. The lower positioning portion 72C can move along the slit 67 between the standby position Pw and a separation / discharge position Pd (see FIG. 10) that is lower than the standby position Pw.

[0121] The surface of the lower positioning portion 72C facing inward (upward) is formed as a positioning surface 72Cf. The positioning surface 72Cf supports the imaging plate 10 on the support surface 64F from below.

[0122] The stage 60 has a spring 72Cs as a biasing member that constantly applies an upward force to the lower positioning portion 72C. For example, on the rear surface side of the plate-shaped portion 64, one end of the spring 72Cs is fixed to the innermost portion of the slit 67, and the other end is fixed to the lower positioning portion 72C. Between the innermost portion of the slit 67 and the lower positioning portion 72C, the spring 72Cs is constantly in an extended state, and the compression force of the spring 72Cs biases the lower positioning portion 72C upward in the second direction F2.

[0123] A shaft portion 72Cq is formed integrally with the lower positioning portion 72C. The shaft portion 72Cq is provided on a portion of the lower positioning portion 72C facing away from the support surface 64F. Here, the shaft portion 72Cq is provided at a position toward the upper end of the lower positioning portion 72C in the longitudinal direction. The shaft portion 72Cq protrudes beyond the rear surface of the plate-shaped portion 64. A link mechanism 85 is connected to the shaft portion 72Cq. In response to operation of the link mechanism 85, the lower positioning portion 72C is driven to move back and forth along the second direction F2. The link mechanism 85 will be described later.

[0124] The stage 60 also has a discharge guide 68 located below the pair of first-direction positioning portions 72A, 72B in the second direction F2. The discharge guide 68 is fixed at a fixed position relative to the plate-shaped portion 64 so as to protrude from the support surface 64F. The discharge guide may be a part formed integrally with the plate-shaped portion.

[0125] In this embodiment, the discharge guide 68 has a plate-shaped portion perpendicular to the support surface 64F, and its upper end protrudes from the support surface 64F adjacent to one side of the lower positioning portion 72C located in the standby position Pw. A discharge guide surface 68g is formed on the upward-facing portion of the discharge guide 68, which faces away from the support surface 64F as it extends downward along the second direction F2.

[0126] The lower positioning portion 72C located at the standby position Pw is positioned higher than the ejection guide surface 68g in the second direction F2. More specifically, the positioning surface 72Cf of the lower positioning portion 72C located at the standby position Pw is positioned higher than the ejection guide surface 68g. Therefore, when the imaging plate 10 on the support surface 64F slides down the support surface 64F due to gravity, the lower edge of the imaging plate 10 is supported by contacting the positioning surface 72Cf before contacting the ejection guide surface 68g.

[0127] Furthermore, the lower positioning portion 72C positioned at the separated discharge position Pd is positioned lower than the discharge guide surface 68g in the second direction F2. More specifically, the positioning surface 72Cf of the lower positioning portion 72C positioned at the separated discharge position Pd is positioned lower than the discharge guide surface 68g. In this state, the imaging plate 10 on the support surface 64F is not supported by the positioning surface 72Cf and comes into contact with the discharge guide surface 68g. Because the discharge guide surface 68g faces downward in a direction gradually protruding from the support surface 64F, the lower edge of the imaging plate 10 is lifted by the discharge guide surface 68g in a direction away from the support surface 64F. This allows the imaging plate 10 to fall downward from the stage 60 without interfering with the positioning surface 72Cf.

[0128] The ejection guide surface 68g may be omitted, in which case, for example, the imaging plate 10 on the stage 60 may be removed by hand.

[0129] The upper positioning portion 72D is a portion located on the other side in the second direction F2, in this case the upper side, of the plate-shaped portion 64. Here, the upper positioning portion 72D is formed separately from the plate-shaped portion 64. The upper positioning portion may be formed integrally with the plate-shaped portion.

[0130] The upper positioning portion 72D is provided opposite to and spaced apart from the lower positioning portion 72C in the second direction F2. Preferably, the lower positioning portion 72C and the upper positioning portion 72D are positioned at the same position in the first direction F1.

[0131] The upper positioning portion 72D protrudes beyond the support surface 64F. The surface of the upper positioning portion 72D that protrudes beyond the support surface 64F and faces inward (downward) forms the positioning surface 72Df. When the lower positioning portion 72C moves upward while the imaging plate 10 supported on the support surface 64F is supported by the positioning surface 72Cf of the lower positioning portion 72C, the imaging plate 10 is pushed upward and moves. Eventually, the upper edge of the imaging plate 10 comes into contact with the upper positioning portion 72D, restricting the upward movement of the imaging plate 10. As a result, the imaging plate 10 is sandwiched between the lower positioning portion 72C and the upper positioning portion 72D in the second direction F2. In this state, the upper edge of the imaging plate 10 comes into contact with the upper positioning surface 72Df, thereby positioning the imaging plate 10 in the first direction.

[0132] When the lower positioning portion 72C is located at the standby position Pw, the distance between the lower positioning portion 72C and the upper positioning portion 72D is set to be larger than the vertical dimension of the imaging plate 10. When imaging plates 10 of a plurality of sizes are selectively set on the stage 60, the distance is set to be larger than the largest vertical dimension of the imaging plates 10 of a plurality of sizes.

[0133] In this embodiment, the imaging plate 10 is set on the stage 60 with the longitudinal direction of the imaging plate 10 aligned with the main scanning direction A1. Therefore, the vertical dimension of the imaging plate 10 is the width of the imaging plate 10 in the longitudinal direction.

[0134] When the lower positioning portion 72C is closest to the upper positioning portion 72D, the distance between the lower positioning portion 72C and the upper positioning portion 72D is set to be smaller than the vertical dimension of the imaging plate 10. When imaging plates 10 of multiple sizes are selectively set on the stage 60, the distance is set to be smaller than the smallest vertical dimension of the imaging plates 10 of the multiple sizes.

[0135] Therefore, with the lower positioning portion 72C located at the standby position Pw, the imaging plate 10 can be disposed between the lower positioning portion 72C and the upper positioning portion 72D. Furthermore, by moving the lower positioning portion 72C from the standby position Pw to the clamping position Ps, the imaging plate 10 can be clamped between the lower positioning portion 72C and the upper positioning portion 72D.

[0136] The positioning surfaces 72Af, 72Baf, 72Bbf, 72Cf, and 72Df may have any shape as long as they are in contact with the edge of the imaging plate 10 and can regulate the position of the edge. For example, the positioning surfaces 72Af, 72Baf, 72Bbf, 72Cf, and 72Df protrude from the support surface 64F by at least the thickness of the imaging plate 10. For example, the positioning surfaces 72Af, 72Baf, 72Bbf, 72Cf, and 72Df may be surfaces perpendicular to the support surface 64F.

[0137] For example, the positioning surfaces 72Af, 72Baf, 72Bbf, 72Cf, and 72Df may be formed in a shape that gradually covers the support surface 64F as it moves away from the support surface 64F (see FIG. 5 for the positioning surfaces 72Cf and 72Df). In this case, the positioning surfaces 72Af, 72Baf, 72Bbf, 72Cf, and 72Df may be flat, curved, or a combination of a flat and a curved surface. If the positioning surfaces 72Af, 72Baf, 72Bbf, 72Cf, and 72Df are shaped so that they extend in a direction that covers the support surface 64F as they move away from the support surface 64F, the positioning surfaces 72Af, 72Baf, 72Bbf, 72Cf, and 72Df can contact the edge of the imaging plate 10 supported on the support surface 64F, positioning the edge from the outside in the extension direction of the support surface 64F and pressing the edge against the support surface 64F. This makes it easier to maintain the imaging plate 10 in contact with the support surface 64F, and when the reading unit 90 reads the imaging plate 10, it is easier to maintain a constant distance between the reading unit 90 and the surface 10a of the imaging plate 10. This allows the reading unit 90 to read the imaging plate 10 properly.

[0138] <Regarding the drive mechanism of the first direction positioning unit and the lower positioning unit> The first direction positioning unit 72A and the lower positioning unit 72C may be driven by any configuration. For example, the first direction positioning unit 72A and the lower positioning unit 72C may be driven by utilizing the force that drives the stage 60. For example, the first direction positioning unit 72A and the lower positioning unit 72C may be driven by a drive unit (e.g., a motor, a solenoid actuator) separate from a drive unit such as a motor that drives the stage 60, based on the control of the control unit 100 (see FIG. 3).

[0139] In this embodiment, the reading device 20 includes a positioning unit operating mechanism 80. The positioning unit operating mechanism 80 causes the first direction positioning mechanism 70 to perform a closing operation and also causes the lower positioning unit 72C of the second direction positioning mechanism 71 to perform a closing operation in accordance with the movement of the stage 60 from the set position P1 to the reading position P2 by the stage moving mechanism 50. An example of the configuration for this purpose will be described below.

[0140] <Configuration for operating the first direction positioning unit> As described above, the first direction positioning part 72B is supported so as to be movable between a distant position and an approach position relative to the stage main body 61. The first direction positioning part 72B is biased in the approach direction by the spring 72Bs. In addition, the roller 72Bq protrudes from the first direction positioning part 72B to the rear surface side of the plate-shaped part 64.

[0141] A cam plate 82 is supported on a portion of the lower short-side side plate 46L that faces the stage 60 (see FIGS. 2 and 4).

[0142] The cam plate 82 is a plate-shaped member located in the first direction F1 between the pair of longitudinal side plates 45. The cam plate 82 is spaced apart from the inner surfaces of the pair of longitudinal side plates 45 in the first direction F1.

[0143] The cam plate 82 protrudes inward and outward from the support frame 44 relative to the short-side side plate 46L. In the first direction F1, the cam plate 82 is located within the range of the movable support body 62 in which the recessed portion 63 is formed. Therefore, when the stage 60 is located at the set position P1 or the discharge position P3, the portion of the cam plate 82 that protrudes into the support frame 44 is located within the recessed portion 63 (see FIG. 1). Therefore, the stage 60 can move toward the set position P1 or the discharge position P3 without interfering with the cam plate 82.

[0144] The side edge of the cam plate 82 on the first direction positioning portion 72A side (inner side) is an operating surface 82f that comes into contact with the roller 72Bq and moves the roller 72Bq along the first direction F1.

[0145] The operating surface 82f has a straight portion 82f1 and an inclined portion 82f2.

[0146] The straight portion 82f1 extends along the second direction F2. The position of the straight portion 82f1 in the first direction F1 is such that, with the roller 72Bq in contact with the straight portion 82f1, the first-direction positioning portion 72B, which is biased by the spring 72Bs, can be restricted to the standby position. Furthermore, in the second direction F2, the straight portion 82f1 is located within a range through which the roller 72Bq passes when the stage 60 moves from the discharge position P3 through the set position P1 to just before the reading position P2. Therefore, the straight portion 82f1 can restrict the position of the first-direction positioning portion 72B when the stage 60 moves from the discharge position P3 through the set position P1 to just before the reading position P2.

[0147] The inclined portion 82f2 is continuous with the straight portion 82f1 upward in the second direction F2. The inclined portion 82f2 is formed in a shape that approaches the first-direction positioning unit 72A as it extends upward along the second direction F2. In addition, in the second direction F2, the inclined portion 82f2 is present in a range through which the roller 72Bq passes when the stage 60 moves from just before the reading position P2 toward the reading position P2. Therefore, the inclined portion 82f2 can regulate the position of the first-direction positioning unit 72B when the stage 60 moves from just before the reading position P2 toward the reading position P2. Here, the inclined portion 82f2 regulates the position of the first-direction positioning unit 72B so that the first-direction positioning unit 72B gradually moves toward the first-direction positioning unit 72A.

[0148] In this embodiment, when the stage 60 reaches the reading position P2, the inclined portion 82f2 does not contact the roller 72Bq. That is, in the second direction F2, the inclined portion 82f2 is present in a range through which the roller 72Bq passes before the stage 60 approaches the reading position P2 from just before the reading position P2 and reaches the reading position P2. Therefore, when the stage 60 reaches the reading position P2, the first-direction positioning unit 72B is in a state in which it can come closest to the first-direction positioning unit 72A.

[0149] <Configuration for operating the lower positioning unit> The positioning unit operating mechanism 80 includes a lower positioning unit operating mechanism 84. The lower positioning unit operating mechanism 84 is a mechanism that moves the lower positioning unit 72C along the second direction F2 in accordance with the movement of the stage 60 from the set position P1 to the reading position P2 by the stage moving mechanism 50.

[0150] The lower positioning unit operating mechanism 84 includes a cam surface 89f and a link mechanism 85.

[0151] The link mechanism 85 includes a first link 86 and a second link 87 as a plurality of links.

[0152] The first link 86 is a long member, and in this case, is a long, thin plate-like member. The first link 86 is located on the back side of the stage main body 61. One end of the first link 86 is rotatably connected to the lower positioning part 72C via a shaft. The other end of the first link 86 extends toward the back side position of the first direction positioning part 72A.

[0153] The second link 87 is an elongated member, and in this case includes a thin plate-shaped member 87a and a cam follower 87b. One end of the second link 87 is rotatably connected to the other end of the first link 86 via a shaft. A longitudinal middle portion of the plate-shaped member 87a is rotatably supported on the rear surface of the stage main body 61 via a support shaft 87c, which serves as a swing fulcrum. The support shaft 87c is located, for example, on the rear surface of the plate-shaped member 64 and above the slit 65b. The support shaft 87c is located, for example, on the rear surface of the plate-shaped member 64, closer to the first-direction positioning member 72B. The position of the support shaft 87c can be appropriately set depending on the amount of movement of the lower positioning member 72C, the position of the cam surface 89f, and the like. The cam follower 87b is a roller rotatably supported on the other end of the plate-shaped member 87a via a shaft.

[0154] The first link 86 extends upward from the point where it is connected to the lower positioning portion 72C while inclining in the second direction F2. The second link 87 extends upward from the point where it is connected to the first link 86 while inclining in the opposite direction to the first link 86. A cam follower 87b at the other end of the second link 87 is located on the side edge of the plate-shaped portion 64 closer to the first-direction positioning portion 72B.

[0155] When the lower positioning portion 72C moves upward in the second direction F2, the first link 86 moves upward, and one end of the second link 87 moves upward. This causes the second link 87 to rotate around the support shaft 87c. For example, in FIG. 4, the second link 87 rotates clockwise around the support shaft 87c. This causes the cam follower 87b to rotate clockwise in the circumferential direction around the support shaft 87c.

[0156] Furthermore, when the lower positioning portion 72C moves downward in the second direction F2, the first link 86 moves downward, and one end of the second link 87 moves downward. This causes the second link 87 to rotate around the support shaft 87c. For example, in FIG. 4, the second link 87 rotates counterclockwise around the support shaft 87c. This causes the cam follower 87b to rotate counterclockwise in the circumferential direction around the support shaft 87c.

[0157] The cam follower may be provided on the first link. The link mechanism may include a larger number of links. The first link may be supported so as to be swingable via a swing fulcrum.

[0158] Lower positioning portion 72C is biased upward by spring 72Cs, and cam follower 87b is biased to rotate clockwise around support shaft 87c. Cam surface 89f controls the position of cam follower 87b in first direction F1, thereby controlling the position of lower positioning portion 72C in second direction F2.

[0159] A cam plate 89 is supported on the support frame 44. In this embodiment, the cam plate 89 is supported on an inward portion of one of the longitudinal side plates 45 of the support frame 44. The cam plate 89 is positioned away from the cam plate 82 in the first direction F1.

[0160] The cam plate 89 protrudes from an inward portion of one of the longitudinal side plates 45 of the support frame 44. The width of the movable support member 62 is set to a degree that allows interference with the cam plate 89 to be avoided in the first direction F1.

[0161] The inward-facing side edge of the cam plate 89 is a cam surface 89f. The cam follower 87b faces the cam surface 89f. The biasing force of the spring 72Cs presses the cam follower 87b against the cam surface 89f. Therefore, as the stage 60 moves, the cam follower 87b moves along the cam surface 89f.

[0162] As the stage 60 moves, the cam surface 89f causes the cam follower 87b to be displaced in a first direction F1, which is a direction intersecting the direction in which the stage 60 moves.

[0163] In this embodiment, the cam surface 89f has a primary cam surface 89f1. The primary cam surface 89f1 extends along the second direction F2. As described above, the cam follower 87b is biased by the biasing force of the spring 72Cs so as to rotate clockwise around the support shaft 87c when viewed from the back side (see FIG. 4). When the cam follower 87b is pressed against the primary cam surface 89f1, the cam follower 87b is restricted from rotating clockwise around the support shaft 87c. Therefore, the lower positioning portion 72C is restricted to be positioned at a fixed position, here, the standby position Pw.

[0164] The main cam surface 89f1 is present within a range through which the cam follower 87b passes while the stage 60 moves from the set position P1 to just before the reading position P2. Therefore, when the stage 60 is positioned at the set position P1, the cam follower 87b contacts the main cam surface 89f1. Even when the stage 60 is positioned just before the reading position P2, the cam follower 87b contacts the main cam surface 89f1. Even when the stage 60 is positioned between the set position P1 and a position just before the reading position P2, the cam follower 87b contacts the main cam surface 89f1. Therefore, while the stage 60 moves from the set position P1 to just before the reading position P2, the lower positioning part 72C is maintained at the standby position Pw.

[0165] Before the stage 60 reaches the reading position P2, the cam follower 87b disengages from the main cam surface 89f1. As a result, the cam follower 87b rotates clockwise around the support shaft 87c due to the biasing force of the spring 72Cs, and the lower positioning part 72C moves from the standby position Pw toward the clamping position Ps.

[0166] An inclined cam surface inclined upward and outward along the second direction F2 may be connected to the main cam surface 89f1 on the reading position P2 side. In this case, the cam follower moves on the inclined cam surface, and the lower positioning part 72C can gradually move from the standby position Pw toward the clamping position Ps.

[0167] In this way, the link mechanism 85 can transmit the displacement of the cam follower 87b in a direction intersecting the direction of movement of the stage 60 as a force that moves the lower positioning portion 72C relative to the stage main body 61. In particular, the cam follower 87b is located on the opposite side of the second link 87 from the end portion that is connected to the first link 86.

[0168] When the stage 60 moves from the set position P1 to the reading position P2, the timing at which the lower positioning unit 72C starts to move from the standby position Pw toward the clamping position Ps may be before, simultaneously with, or after the timing at which the first direction positioning unit 72B starts to move from the separated position to the approaching position. In this embodiment, the timing at which the lower positioning unit 72C starts to move from the standby position Pw toward the clamping position Ps is after the timing at which the first direction positioning unit 72B starts to move from the separated position to the approaching position.

[0169] Therefore, when the stage 60 moves from the set position P1 to the reading position P2, the roller 72Bq comes into contact with the inclined portion 82f2, and then the cam follower portion 87b comes off the main cam surface 89f1.

[0170] In this embodiment, the cam surface 89f has a retraction operation cam surface 89f2. The retraction operation cam surface 89f2 is continuous with the main cam surface 89f1 on the lower side. The retraction operation cam surface 89f2 protrudes further toward the first-direction positioning part 72A in the first direction F1 than the main cam surface 89f1. More specifically, the retraction operation cam surface 89f2 includes a surface that protrudes inward from the lower end of the main cam surface 89f1 in the first direction F1, and an inclined surface that gradually slopes outward from the inner end of the surface downward.

[0171] When the stage 60 moves from the set position P1 toward the discharge position P3, the cam follower 87b rides up on the retraction operation cam surface 89f2 and is pushed inward. This causes the second link 87 to rotate around the support shaft 87c (counterclockwise when viewed from the back side), and the first link 86 is pushed downward. Then, the lower positioning part 72C moves from the standby position Pw to the separation discharge position Pd.

[0172] <About the operation of the reader> The operation of the reading device 20 will now be described. Figures 6 to 9 are diagrams illustrating the operation of the positioning unit operating mechanism 80, with the stage 60 viewed from the front. Note that Figures 6 to 9 illustrate the smallest and most easily tilted imaging plate 10 (an imaging plate called size 0 (the size used clinically for standard pediatric radiography)). These figures will be referenced as necessary.

[0173] In the initial state, the stage 60 is located at the set position P1 (see FIGS. 3 to 5 and 6). In this state, the roller 72Bq is in contact with the linear portion 82f1 of the operating surface 82f, and the first-direction positioning portion 72B is located at the separated position. Therefore, the first-direction positioning portions 72A and 72B are separated from each other in the first direction F1 (horizontal direction). Furthermore, the cam follower 87b is in contact with the main cam surface 89f1 of the cam surface 89f, and the lower positioning portion 72C is located at the standby position Pw. Therefore, the lower positioning portion 72C and the upper positioning portion 72D are separated from each other in the second direction F2.

[0174] In this state, the imaging plate 10 is inserted into the insertion port 31 (see FIG. 1). The imaging plate 10 is guided by the guide surface 202 toward the support surface 64F of the stage 60. The imaging plate 10 is supported on the stage 60 with the back surface 10b of the imaging plate 10 in contact with the support surface 64F and with the lower edge of the imaging plate 10 in contact with the positioning surface 72Cf of the lower positioning portion 72C.

[0175] When a reading command is input to the reader 20, the stage moving mechanism 50 drives the stage 60 to move from the set position P1 toward the reading position P2. At the beginning of the movement, the roller 72Bq moves on the linear portion 82f1 of the operating surface 82f, and the cam follower 87b moves on the main cam surface 89f1 of the cam surface 89f. As a result, the first direction positioning unit 72B is positioned in the separated position, and the lower positioning unit 72C is maintained in the standby position Pw. In other words, the lower positioning unit 72C is stationary at this time.

[0176] Before the stage 60 reaches the reading position P2, the roller 72Bq moves from the straight portion 82f1 to the inclined portion 82f2 of the operating surface 82f (see FIG. 7). Therefore, the first-direction positioning unit 72B is biased toward the first-direction positioning unit 72A by the spring 72Bs, and the roller 72Bq moves along the inclined portion 82f2 as the stage 60 moves. This causes the first-direction positioning unit 72B to move toward the first-direction positioning unit 72A. When the first-direction positioning unit 72B starts to move toward the first-direction positioning unit 72A, the cam follower 87b is in contact with the main cam surface 89f1 of the cam surface 89f, so the lower positioning unit 72C is maintained at the standby position Pw. In other words, the first-direction positioning unit 72B starts to move in the closing direction while the lower positioning unit 72C remains stopped at the standby position Pw.

[0177] As the stage 60 moves further toward the reading position P2, the biasing force of the spring 72Bs causes the first-direction positioning part 72B to move further toward the first-direction positioning part 72A (see FIG. 8). Then, when the central axis of the cam follower 87b passes the end of the main cam surface 89f1, the cam follower 87b becomes able to move outward in the first direction F1, and the lower positioning part 72C becomes able to move upward relative to the stage main body 61 along the second direction F2. Then, the biasing force of the spring 72Cs causes the lower positioning part 72C to move upward relative to the stage main body 61.

[0178] Here, it is preferable that the lower positioning unit 72C can move along the second direction F2 relative to the stage body 61 during at least a portion of the movement period of the first direction positioning unit 72B. It is also preferable that the lower positioning unit starts moving along the second direction before the distance between the first direction positioning unit 72A and the first direction positioning unit 72B becomes equal to the width of the imaging plate 10. The movement period of the first direction positioning unit 72B is the period during which the roller 72Bq is in contact with the inclined portion 82f2, or the period during which the roller 72Bq is in contact with the inclined portion 82f2 plus the period during which the roller 72Bq moves over the inclined portion 82f2 along the first direction F1. In this embodiment, the lower positioning unit 72C can start moving along the second direction F2 during the period during which the roller 72Bq is in contact with the inclined portion 82f2.

[0179] It is also possible to configure the lower positioning unit so that it can start moving in the second direction by the time the moving operation period of the first direction positioning unit starts, as will be described later in the modified example.

[0180] When the stage 60 moves further toward the reading position P2, the biasing force of the spring 72Bs causes the first-direction positioning part 72B to move further toward the first-direction positioning part 72A, and the imaging plate 10 becomes sandwiched between the first-direction positioning part 72B and the first-direction positioning part 72A (see FIG. 9). Then, the movement of the roller 72Bq toward the first-direction positioning part 72A is restricted, and the roller 72Bq moves along the second direction F2 while moving away from the inclined part 82f2.

[0181] Furthermore, when the cam follower 87b passes the end of the main cam surface 89f1, the cam follower 87b becomes able to move further outward in the first direction F1, and the lower positioning portion 72C becomes able to move further upward in the second direction F2 relative to the stage main body 61. Then, due to the biasing force of the spring 72Cs, the lower positioning portion 72C moves further upward relative to the stage main body 61. As a result, the imaging plate 10 sandwiched between the pair of first direction positioning portions 72A, 72B in the first direction F1 can be sandwiched between the upper positioning portion 72D and the lower positioning portion 72C in the second direction F2.

[0182] As described above, even when the pair of first-direction positioning units 72A, 72B sandwich the imaging plate 10, the sandwiching is performed by the biasing force of the spring 72Bs. Therefore, by appropriately adjusting the biasing force of the spring 72Bs, the imaging plate 10 can be slid relative to the pair of first-direction positioning units 72A, 72B. This allows the imaging plate 10 to be sandwiched between the lower positioning unit 72C and the upper positioning unit 72D along the second direction F2.

[0183] As described above, it is preferable that the upper positioning portion 72D and the lower positioning portion 72C sandwich the imaging plate 10 in the second direction F2 while the pair of first-direction positioning portions 72A, 72B sandwich the imaging plate 10 in the first direction F1. In other words, it is preferable that the operating surface 82f and the cam surface 89f are adjusted so that the lower positioning portion 72C can approach the upper positioning portion 72D sufficiently to sandwich the imaging plate 10 while the distance between the first-direction positioning portions 72A, 72B is sufficient to sandwich the imaging plate 10.

[0184] When imaging plates 10 of multiple sizes are expected, it is preferable to clamp at least one of the imaging plates 10 of multiple sizes at the above timing, and it is preferable to clamp all of the imaging plates 10 of multiple sizes at the above timing.

[0185] The stage 60 holding the imaging plate 10 moves to the reading position P2, whereby the reading unit 90 reads the latent image on the imaging plate 10.

[0186] After the reading by the reading unit 90 is completed, the stage 60 returns to the set position P1. During this movement, the above-described operations are reversed, and the stage 60 releases the holding of the imaging plate 10.

[0187] When the stage 60 moves from the set position P1 toward the ejection position P3, the cam follower 87b rides up onto the retraction operation cam surface 89f2 of the cam surface 89f and moves inward in the second direction (see FIG. 10). Then, the second link 87 rotates around the support shaft 87c, and the first link 86 is pressed downward. This causes the lower positioning portion 72C to move downward. When the positioning surface 72Cf moves below the ejection guide surface 68g, the lower edge of the imaging plate 10, which was supported by the positioning surface 72Cf, comes into contact with the ejection guide surface 68g. The imaging plate 10 moves downward along the ejection guide surface 68g due to its own weight. Therefore, the imaging plate 10 is guided by the ejection guide surface 68g so as to be separated from the support surface 64F by at least the height of the positioning surface 72Cf, and falls downward. This causes the imaging plate 10 to be ejected.

[0188] An operation for correcting the posture of the imaging plate 10 when the imaging plate 10 placed on the support surface 64F at the set position P1 is tilted will be described.

[0189] When the stage 60 moves from the set position P1 to the read position P2, the first-direction positioning unit 72B moves first. The first-direction positioning unit 72B has positioning surfaces 72Baf, 72Bbf as multiple first-direction movable positioning surfaces spaced apart along the second direction F2. This allows the positioning surfaces 72Baf, 72Bbf to be configured so that the corners of a tilted imaging plate 10 are unlikely to come into direct contact with the positioning surfaces 72Baf, 72Bbf (see FIG. 11). For example, the positioning surfaces 72Baf, 72Bbf can be configured so that they are not positioned to the sides of the upper and lower corners of the imaging plate 10, relative to the lower positioning unit 72C positioned at the standby position Pw. When imaging plates 10 of multiple sizes are present, the smallest imaging plate 10 is likely to tilt, so it is recommended that the smallest imaging plate 10 be considered. One of the positioning surfaces 72Baf, 72Bbf can press the edge of the long side of the imaging plate 10 that is tilted relative to the second direction F2, rather than the corner of the tilted imaging plate 10, along the first direction F1. This makes it easy to correct any tilt of the imaging plate 10. Furthermore, when positioning a large imaging plate 10, positioning in the first direction F1 can be performed using the lower positioning surface 72Baf and the upper positioning surface 72Bbf, so the large imaging plate 10 can be accurately positioned at two locations, top and bottom.

[0190] However, there may be cases where the edge of the imaging plate 10 is difficult to move relative to the positioning surface 72Af or the positioning surfaces 72Baf and 72Bbf, making it impossible to correct the tilt by moving the first-direction positioning unit 72B. For example, if the positioning surface 72Af is inclined, a corner of the imaging plate 10 may be pinched between the support surface 64F and the positioning surface 72Af. The movement of the first-direction positioning unit 72B toward the first-direction positioning unit 72A is an action that presses the corner firmly against the positioning surface 72Af. In this case, the corner becomes even more difficult to move relative to the positioning surface 72Af in the second direction F2, making it difficult to correct the tilt of the imaging plate 10 (see FIG. 12). Note that in the example of FIG. 12, it is easily conceivable that the edge of the imaging plate 10 is difficult to move relative to the positioning surface 72Bbf. For example, in Figure 12, the upper left corner of imaging plate 10 is pressed against positioning surface 72Bbf from below, making it difficult for the edge of imaging plate 10 to move smoothly along positioning surface 72Bbf, and it is thought that correcting the tilt of imaging plate 10 may become difficult.

[0191] Therefore, the lower positioning unit 72C is moved along the second direction F2. Preferably, the movement of the lower positioning unit 72C is started before the start of the movement operation period of the first direction positioning unit 72B. As a result, the imaging plate 10 moves upward along the second direction F2. Even if the corners of the imaging plate 10 are difficult to move relative to the positioning surfaces 72Af or 72Baf, 72Bbf, the corners are pushed upward along the second direction F2. This makes it easier for the corners of the imaging plate 10 to move relative to the positioning surfaces 72Af or 72Baf, 72Bbf. In this state, the biasing force of the spring 72Bs moves the first direction positioning unit 72B further to a closer position, smoothly correcting the tilt of the imaging plate 10.

[0192] 12, when the upper left corner of the imaging plate 10 is pressed against the positioning surface 72Bbf from below, the imaging plate 10 can be displaced downward by moving the downward positioning unit 72C downward, which may suppress strong interference between the upper left corner of the imaging plate 10 and the positioning surface 72Bbf and effectively correct the tilt of the imaging plate 10. An example of moving the downward positioning unit 72C downward will be described in a modified example below.

[0193] <Effects, etc.> The advantage of the present disclosure is that it allows for flexible design so that each positioning unit (72B, 72C) can be moved or stopped (standby) at the optimal timing by using cam and link combination methods, structures, etc. Both the first direction positioning unit 72B and the lower positioning unit 72C can be freely opened, closed, or stopped at the desired timing (one positioning unit can be stopped while the other is moving, or the movement of a specific positioning unit can be temporarily stopped, etc.). This prevents the imaging plate 10 from being pinched at an angle (clogging).

[0194] In the radiation image reading device 20 configured as described above, the first-direction positioning unit 72B, which is at least one of the pair of first-direction positioning units 72A and 72B, moves along the first direction F1, thereby sandwiching the imaging plate 10 on the support surface 64F along the first direction F1. At this time, depending on the inclination of the imaging plate 10 on the stage body 61, it is conceivable that the pair of first-direction positioning units 72A and 72B will sandwich the imaging plate 10 at an angle. In such a case, by moving the lower positioning unit 72C along the second direction F2, the imaging plate 10 moves along the second direction F2 between the pair of first-direction positioning units 72A and 72B, forcibly moving the contact points of the imaging plate 10 with the pair of first-direction positioning units 72A and 72B along the second direction F2. This makes it easier to eliminate the situation where the pair of first-direction positioning units 72A and 72B sandwich the imaging plate 10 at an angle. Then, by further closing the pair of first direction positioning portions 72A, 72B, the imaging plate 10 is corrected to assume the correct position on the support surface 64F, and the imaging plate 10 is held in the correct position.

[0195] In particular, because the lower positioning unit 72C moves along the second direction F2 during at least part of the movement period of the stage 60, the movement of the first direction positioning unit 72B in the first direction F1 and the movement of the imaging plate 10 in the second direction F2 tend to occur at least temporarily simultaneously. This makes it easier for the imaging plate 10 to move in contact with the first direction positioning unit 72B along the second direction F2. This makes it less likely for the pair of first direction positioning units 72A, 72B to sandwich the imaging plate 10 at an angle.

[0196] Furthermore, because the first-direction positioning unit 72B has positioning surfaces 72Baf, 72Bbf as multiple first-direction movable positioning surfaces spaced apart in the second direction F2, any one of the multiple positioning surfaces 72Baf, 72Bbf can easily press the imaging plate 10 along the second direction F2 at a position where the imaging plate 10 can rotate. This makes it less likely that a corner of the imaging plate 10 will be pressed hard against one position on the positioning surface, making it difficult to move and making it difficult to correct the tilt, and makes it easier to correct the tilt of the imaging plate 10.

[0197] Furthermore, the stage 60 can support imaging plates 10 of multiple sizes, and the first-direction positioning units 72A, 72B move between a position where the largest imaging plate 10 of the multiple sizes can be sandwiched and a position where the smallest imaging plate 10 can be sandwiched. In such a case, if there is a sufficient width between the pair of first-direction positioning units 72A, 72B to sandwich the largest imaging plate 10, when the smallest imaging plate 10 is placed therebetween, the imaging plate 10 is likely to tilt. In such a case, the imaging plate 10 can be effectively corrected by moving the lower positioning unit 72C in the second direction F2 to move the imaging plate 10 in the second direction.

[0198] The second-direction positioning mechanism 71 also includes an upper positioning portion 72D. With the pair of first-direction positioning portions 72A and 72B sandwiching the imaging plate 10 in the first direction F1, the upper positioning portion 72D and the lower positioning portion 72C sandwich the imaging plate 10 in the second direction F2. Therefore, after the pair of first-direction positioning portions 72A and 72B correct the tilt of the imaging plate 10, the upper positioning portion 72D and the lower positioning portion 72C sandwich the imaging plate 10 in the second direction F2, thereby positioning the imaging plate 10 in the second direction F2. Furthermore, when the pair of first-direction positioning portions 72A and 72B correct the tilt of the imaging plate 10, the upper positioning portion 72D is positioned above and away from the upper edge of the imaging plate 10. This makes it difficult for the imaging plate 10 to interfere with the upper positioning portion 72D, and the tilt can be smoothly corrected. This configuration is also excellent for gripping a warped imaging plate 10 during imaging. Reading the latent image on the imaging plate with reduced bending is essential to obtaining clear, high-definition image data. If the imaging plate 10 is significantly bent, it is desirable to position the imaging plate 10 in the order of contact correction by contacting the long sides of the imaging plate followed by contact correction by contacting the short sides. Therefore, by first positioning the long sides (positioning in the first direction in this embodiment), it is expected that even a bent imaging plate 10 can be securely clamped and corrected to the correct posture.

[0199] Furthermore, the pair of first direction positioning portions 72A, 72B sandwich the imaging plate 10 with the biasing force of the spring 72Bs acting therebetween. Therefore, with the biasing force of the spring 72Bs acting, the imaging plate 10 can be moved in the second direction F2 by moving the lower positioning portion 72C, thereby positioning the imaging plate 10 in the second direction F2.

[0200] The stage 60 also has a discharge guide surface 68g, and the lower positioning portion 72C moves in the second direction F2 between a separated discharge position Pd below the discharge guide surface 68g and a clamping position Ps above the discharge guide surface 68g. When the lower positioning portion 72C is positioned at the separated discharge position Pd, if the imaging plate 10 falls due to gravity, the discharge guide surface 68g guides the imaging plate 10 in a direction away from the support surface 64F, allowing the imaging plate 10 to be easily discharged. By moving the lower positioning portion 72C upward from the discharge guide surface 68g, the imaging plate 10 can be supported from below on the support surface 64F by the lower positioning portion 72C.

[0201] Furthermore, the positioning unit operating mechanism 80 can cause the first direction positioning mechanism 70 to perform a closing operation and operate the lower positioning unit 72C of the second direction positioning mechanism 71 in conjunction with moving the stage 60 from the set position P1 to the reading position P2. This allows the imaging plate 10 to be positioned smoothly and quickly while the stage 60 is moving. Furthermore, if the power generated by the movement of the stage 60 is used to operate the positioning mechanisms (70, 71), it is expected that the number of driving units can be reduced.

[0202] Furthermore, cooperation between link mechanism 85 and cam surface 89f causes the cam follower to displace in a direction intersecting the direction of stage movement as the stage moves, and this displacement can be transmitted as a force that moves lower positioning unit 72C relative to stage main body 61. This eliminates the need to provide a separate drive source for moving lower positioning unit 72C.

[0203] Furthermore, because the biasing force of spring 72Cs presses cam follower 87b against cam surface 89f, cam follower 87b can be positioned in accordance with cam surface 89f. Depending on how the cam surface restricts the cam follower, the biasing force of spring 72Cs can move lower positioning portion 72C upward. This eliminates the need for a separate drive source to move lower positioning portion 72C.

[0204] {Variation} It is expected that the tilt of the imaging plate 10 can be corrected if the lower positioning portion 72C moves before and after the pair of first direction positioning portions 72A, 72B sandwich the imaging plate 10. Therefore, the movement timing and movement speed of the first direction positioning portion 72B and the lower positioning portion 72C are not limited to the above example and can be set appropriately.

[0205] A modified reading device 520 will be described below with reference to Figures 13 to 16. Reading device 520 according to the modified example differs from reading device 20 in that operating surface 582f of cam plate 582 corresponding to cam plate 82 is different from operating surface 82f, cam surface 589f of cam plate 589 corresponding to cam plate 89 is different from cam surface 89f, and sub-cam surface 592f is added.

[0206] That is, the cam plate 582 is fixed to the short-side side plate 46L instead of the cam plate 82. The side edge of the cam plate 582 on the first-direction positioning portion 72A side (inner side) is an operating surface 582f that comes into contact with the roller 72Bq and moves the roller 72Bq along the first direction F1.

[0207] The actuation surface 582f has a straight portion 582f1 and an inclined portion 582f2.

[0208] The straight portion 582f1 is shorter than the straight portion 82f1. When the stage 60 is positioned at the set position P1, the discharge position P3, or between them, the roller 72Bq comes into contact with the straight portion 582f1.

[0209] The inclined portion 582f2 is formed over a longer section in the second direction F2 than the inclined portion 82f2. When the stage 60 moves from the set position P1 to the reading position P2, the roller 72Bq immediately comes into contact with the inclined portion 582f2.

[0210] In this embodiment, the inclined portion 582f2 is formed in a shape in which the inclination changes midway. For example, in the second direction F2, the inclination of the middle section of the inclined portion 582f2 is smaller than that of the sections at both ends. Therefore, when the stage 60 moves from the set position P1 to the reading position P2, the first direction positioning unit 72B can move faster in the initial and final stages of the movement of the stage 60 than in the intermediate stages of the movement.

[0211] Furthermore, for example, a reverse inclined portion 582f2r is formed in the middle of the inclined portion 582f2. When the roller 72Bq comes into contact with the reverse inclined portion 582f2r, the first-direction positioning unit 72B can temporarily move in an opening direction. By temporarily moving the first-direction positioning unit 72B in the opening direction, even if the edge of the imaging plate 10 becomes jammed between the positioning surfaces 72Baf, 72Bbf and the support surface 64F, the jammed state is easily resolved.

[0212] The cam plate 589 is fixed to the support frame 44 in place of the cam plate 89. The inward-facing side edge of the cam plate 589 is a cam surface 589f. The cam follower 87b moves along the cam surface 589f.

[0213] In this modified example, the cam surface 589f has an inclined cam surface 589f1, a concave cam surface 589f2, and a straight cam surface 589f3, and these cam surfaces 589f1, 589f2, and 589f3 are arranged in this order in an upward direction.

[0214] Inclined cam surface 589f1 is inclined upward and outward in the first direction F1. Concave cam surface 589f2 is a surface that is concave outward in the first direction F1. Straight cam surface 589f3 is formed in a straight line along the second direction F2.

[0215] When the stage 60 is positioned at the set position P1, the cam follower 87b contacts the middle portion of the inclined cam surface 589f1, and the lower positioning portion 72C is positioned at the standby position. When the stage 60 initially moves from the set position P1 toward the reading position P2, the cam follower 87b moves along the inclined cam surface 589f1 and also moves toward the rear of the concave cam surface 589f2. As the stage 60 further moves toward the reading position P2, the cam follower 87b moves away from the concave cam surface 589f2 and then moves on the straight cam surface 589f3. Just before the stage 60 reaches the reading position P2, the cam follower 87b clears the straight cam surface 589f3.

[0216] A sub-cam plate 592 is fixed to a portion of the short-side side plate 46L opposite the cam surface 589f. The surface of the sub-cam plate 592 facing inward in the first direction is the sub-cam surface 592f. The sub-cam surface 592f is located on the opposite side of the support shaft 87c, which serves as the swing fulcrum, from the cam surface 589f. In this modified example, the sub-cam surface 592f is an element of a lower positioning unit operating mechanism that moves the lower positioning unit 72C along the second direction F2 in accordance with the movement of the stage 60.

[0217] A sub cam follower 587b is added to the link mechanism 85. The sub cam follower 587b is located on the opposite side of the support shaft 87c, which serves as the swing fulcrum, from the cam follower 87b. In this modification, the sub cam follower 587b is supported on the support shaft that connects the first link 86 and the second link 87. The sub cam follower 587b may be, for example, a rotatable roller.

[0218] Then, sub cam follower 587b comes into contact with sub cam surface 592f on the side of support shaft 87c opposite cam surface 589f and cam follower 87b. In this modified example, sub cam surface 592f is linear and extends along second direction F2, and sub cam follower 587b comes into contact with sub cam surface 592f while stage 60 is moving from set position P1 toward reading position P2. The timing at which sub cam follower 587b comes into contact with sub cam surface 592f is the timing at which cam follower 87b leaves concave cam surface 589f2.

[0219] When the sub-cam follower 587b contacts the sub-cam surface 592f, the sub-cam follower 587b is displaced inward in the first direction F1. The link mechanism 85 transmits this displacement as a force that moves the lower positioning portion 72C downward relative to the stage main body 61. That is, the longitudinal intermediate portion of the second link 87 is rotatably supported at a fixed position on the stage main body 61 by the support shaft 87c. The lower end of the first link 86 is connected to the lower positioning portion 72C and supported so as to be movable only in the second direction F2. In view of the degree of freedom of each link 86, 87, when the sub-cam follower 587b, located at the connection point between the first link 86 and the second link 87, moves inward in the second direction F2, the first link 86 and the second link 87 are deformed so as to stretch between the support shaft 87c and the lower positioning portion 72C. As a result, the lower positioning portion 72C moves downward relative to the stage main body 61.

[0220] The operation of the reader 20 according to this modified example will be described, focusing on the clamping operation of the imaging plate 10.

[0221] 13, when the stage 60 is in the set position P1, the roller 72Bq is in contact with the straight portion 582f1. The cam follower 87b is in contact with the middle of the inclined cam surface 589f1. The sub-cam follower 587b is positioned away from the sub-cam surface 592f in the second direction F2.

[0222] 14, the stage 60 moves from the set position P1 to the reading position P2. As a result, the roller 72Bq moves from the straight portion 582f1 to the inclined portion 582f2, and then moves along the inclined portion 582f2. As a result, the first direction positioning unit 72B moves in the closing direction along the first direction F1.

[0223] When the stage 60 is in the set position P1, the cam follower 87b is located on the inclined cam surface 589f1. Therefore, as soon as the stage 60 starts to move, the cam follower 87b moves outward in the first direction F1, and the lower positioning portion 72C moves upward relative to the stage 60.

[0224] Therefore, the downward positioning portion 72C can start moving along the second direction F2 by the time the moving operation period of the first direction positioning portion 72B starts.

[0225] Cam follower 87b moves along inclined cam surface 589f1, then enters concave cam surface 589f2, and then rides up onto straight cam surface 589f3. Before cam follower 87b moves along inclined cam surface 589f1 and enters concave cam surface 589f2, cam follower 87b moves outward in first direction F1, and therefore lower positioning portion 72C moves upward relative to stage 60.

[0226] With cam follower 87b inside concave cam surface 589f2, sub cam follower 587b comes into contact with sub cam surface 592f. Sub cam follower 587b rides up on sub cam follower 587b, and thus sub cam follower 587b moves inward in second direction F2. As a result, lower positioning portion 72C moves downward relative to stage main body 61.

[0227] At this time, when sub cam follower 587b rides up on sub cam surface 592f, second link 87 rotates clockwise around support shaft 87c when viewed from the back side. In other words, the direction in which sub cam surface 592f presses sub cam follower 587b due to movement of stage 60 is close to the direction in which sub cam follower 587b moves. As a result, the force moving stage 60 can smoothly press and move sub cam follower 587b, and lower positioning portion 72C can be smoothly and temporarily moved downward relative to stage 60.

[0228] By moving the lower positioning portion 72C at the beginning of clamping by the first-direction positioning portions 72A and 72B, the imaging plate 10 moves in the second direction F2 relative to the first-direction positioning portions 72A and 72B, which easily corrects the tilt of the imaging plate 10. In other words, because the lower positioning portion 72C moves when the first-direction positioning portion 72B starts to move, even if the imaging plate 10 is significantly tilted between the first-direction positioning portions 72A and 72B in the initial state, the corners of the imaging plate 10 are forcibly displaced in the second direction F2 relative to the first-direction positioning portions 72A and 72B, and the tilt of the imaging plate 10 is effectively corrected.

[0229] 14, the movement of the lower positioning part 72C is configured to move upward once relative to the stage 60 and then move downward, but it may also be configured to move downward temporarily without moving upward relative to the stage 60. Depending on the combination of cams and links, each positioning part can be freely made to move in an optimal manner.

[0230] In this configuration in which the lower positioning portion 72C is temporarily displaced downward, the displacement of the lower positioning portion 72C in the direction of gravity causes a change (to reduce) in the coefficient of friction at the contact portion between the imaging plate 10 and the lower positioning portion 72C, which in turn forcibly displaces the edge of the imaging plate 10 along the second direction F2 relative to the first direction positioning portions 72A, 72B, effectively correcting the inclination of the imaging plate 10.

[0231] As shown in FIG. 15, when the stage 60 moves further toward the reading position P2, the roller 72Bq passes through the reverse inclined portion 582f2r and moves over the middle and end portions of the inclined portion 582f2. As the roller 72Bq moves over the reverse inclined portion 582f2r, the first-direction positioning portion 72B temporarily moves in an opening direction. This allows the imaging plate 10 to be temporarily released from the clamping position even if it is tightly clamped between the pair of first-direction positioning portions 72A and 72B. This makes it easier to release the constraint on the imaging plate 10. This allows the tilt of the imaging plate 10 to be corrected more effectively.

[0232] If the imaging plate 10 is sandwiched between the pair of first direction positioning parts 72A and 72B during the movement of the first direction positioning part 72B, the movement of the first direction positioning part 72B in the first direction F1 stops, and the roller 72Bq moves away from the inclined part 582f2.

[0233] Because the cam follower 87b moves on the linear cam surface 589f3, the lower positioning portion 72C is maintained at a constant position relative to the stage body 61. When the cam follower 87b clears the linear cam surface 589f3, the lower positioning portion 72C moves upward relative to the stage body 61. As a result, the imaging plate 10 is sandwiched between the pair of first-direction positioning portions 72A and 72B and pushed from below along the second direction F2, causing it to move. At this time, as described in the embodiment, the tilt of the imaging plate 10 is effectively corrected. In this modification, too, it is preferable that the timing at which the lower positioning portion 72C moves upward until the imaging plate 10 can be sandwiched and positioned between the upper positioning portion 72D and the lower positioning portion 72C in the second direction F2 occurs after the pair of first-direction positioning portions 72A and 72B have sandwiched and positioned the imaging plate 10 in the first direction F1.

[0234] 16, when the stage 60 moves from the reading position P2 to the ejection position P3, the cam follower 87b moves along the inclined cam surface 589f1, thereby moving inward in the first direction F1. This causes the lower positioning portion 72C to move downward, and as described in the embodiment, the imaging plate 10 is ejected from the stage 60 by the ejection guide surface 68g.

[0235] Furthermore, in order for lower positioning portion 72C to move downward relative to stage body 61 before lower positioning portion 72C starts to move upward relative to stage body 61, for example, as shown in Fig. 17, an actuating surface 682f corresponding to actuating surface 582f and a cam surface 689f corresponding to cam surface 589f may be set as follows: Note that for ease of understanding, actuating surface 582f and cam surface 589f are shown in Fig. 17.

[0236] That is, the actuation surface 682f has a straight portion 682f1 and an inclined portion 682f2.

[0237] The straight portion 682f1 is formed in a section closer to the set position P1 than the inclined portion 682f2. The inclined portion 682f2 is continuous with the end of the straight portion 682f1 that is farther from the set position P1. The inclined portion 682f2 is inclined so as to incline toward the first direction positioning portion 72A as it extends in the second direction F2 in a direction away from the set position P1. In the second direction F2, the inclined portion 682f2 exists in a section that is longer than the straight portion 682f1.

[0238] When the stage 60 is located at the set position P1, the roller 72Bq is in contact with the straight portion 682f1. When the stage 60 moves from the set position P1 to the reading position P2, the roller 72Bq passes through the straight portion 682f1 and comes into contact with the inclined portion 682f2. Before the stage 60 reaches the reading position P2, the roller 72Bq moves over the inclined portion 682f2 toward the reading position P2.

[0239] The cam surface 689f has a first linear cam surface 689f1, a second linear cam surface 689f2, and a stepped cam surface 689fS between the linear cam surface 689f1 and the second linear cam surface 689f2.

[0240] The first linear cam surface 689f1 is located closer to the set position P1 than the second linear cam surface 689f2. The second linear cam surface 689f2 is closer to the first-direction positioning unit 72A than the first linear cam surface 689f1. The stepped cam surface 689fS is a step that extends from the end of the first linear cam surface 689f1 opposite the set position P1 toward the first-direction positioning unit 72B. The stepped cam surface 689fS may be a surface that inclines toward the first-direction positioning unit 72A as it moves away from the set position P1 in the second direction F2.

[0241] When the stage 60 is in the set position P1, the cam follower 87b is in contact with the first linear cam surface 689f1, the lower positioning portion 72C is in the standby position, and the roller 72Bq is in contact with the linear portion 682f1.

[0242] When the stage 60 initially moves from the set position P1 toward the reading position P2, the cam follower 87b moves along the first linear cam surface 689f1 and reaches the stepped cam surface 689fS. When the stage 60 further moves to the reading position P2, the cam follower 87b moves over the stepped cam surface 689fS and begins to move on the second linear cam surface 689f2.

[0243] When the cam follower 87b moves over the stepped cam surface 689fS, the sub cam follower 587b comes into contact with the sub cam surface 592f, as described above. This causes the sub cam follower 587b to be displaced inward in the first direction F1. The link mechanism 85 transmits this displacement as a force that moves the lower positioning part 72C downward relative to the stage main body 61. This causes the lower positioning part 72C to move downward relative to the stage main body 61.

[0244] At the timing when the cam follower 87b moves over the stepped cam surface 689fS and the sub cam follower 587b comes into contact with the sub cam surface 592f, the roller 72Bq is moving along the straight line portion 682f1. Therefore, the first direction positioning portion 72B is not moving along the first direction F1 relative to the stage main body 61.

[0245] When the stage 60 moves further toward the reading position P2, the cam follower 87b moves on the second linear cam surface 689f2. In this state, the lower positioning portion 72C maintains a fixed position relative to the stage main body 61.

[0246] While the cam follower 87b moves on the second linear cam surface 689f2, the roller 72Bq moves from the linear portion 682f1 to the inclined portion 682f2, and the first positioning portion 72B can move toward the first positioning portion 72A along the first direction F1.

[0247] In this embodiment, the roller 72Bq moves beyond the inclined portion 682f2 before the cam follower 87b moves beyond the second linear cam surface 689f2. Therefore, after the period in which the imaging plate 10 is sandwiched between the first positioning portions 72A and 72B ends, the lower positioning portion 72C moves further upward, and can sandwich the imaging plate 10 between itself and the upper positioning portion 72D.

[0248] This allows the lower positioning portion 72C to move downward relative to the stage main body 61 before the lower positioning portion 72C starts to move upward relative to the stage main body 61.

[0249] As in this example, the movement operation period of lower positioning unit 72C and the movement operation period of first positioning units 72A and 72B may be set to be exclusive, i.e., not overlapping with each other. In the example shown in FIG. 17, first linear cam surface 689f1 and stepped cam surface 689fS, as well as the components related to sub-cam follower 587b and sub-cam surface 592f, may be omitted. In this case, after the movement operation periods of first positioning units 72A and 72B end, lower positioning unit 72C moves upward relative to stage main body 61.

[0250] According to this modification, the downward-direction positioning unit 72C can start moving along the second direction F2 by the start of the movement operation period of the first-direction positioning unit 72B. Therefore, if the imaging plate 10 is significantly tilted, the imaging plate 10 is first displaced in the second direction F2 (for example, moved downward), and then the first-direction positioning unit 72A and the first-direction positioning unit 72B can start clamping the imaging plate 10. As a result, when the first-direction positioning unit 72A and the first-direction positioning unit 72B start clamping the imaging plate 10, the tilt of the imaging plate 10 is corrected, and the imaging plate 10 can be clamped. This more reliably prevents the first-direction positioning unit 72A and the first-direction positioning unit 72B from clamping the imaging plate 10 while it is tilted.

[0251] Furthermore, while the lower positioning portion 72C is moving upward relative to the stage body 61, the lower positioning portion 72C stops relative to the stage body 61. Therefore, the lower positioning portion 72C can be moved at a high speed in the initial stage of its movement, making it easier to correct the tilt of the imaging plate 10.

[0252] Here, if the tilt of the imaging plate 10 is not corrected, and the lower positioning portion 72C continues to move, the corners of the imaging plate 10 may be pressed strongly against the positioning surfaces 72Baf, 72Bbf. Therefore, by stopping the lower positioning portion 72C midway through its movement after moving it at high speed, the imaging plate 10 can be maintained in a position where it is less likely to interfere strongly with the first direction positioning portion 72B.

[0253] The straight cam surface 589f3 is an inclined cam surface 589f3a (see Figure 13) that is inclined at an angle smaller than that of the inclined cam surface 589f1, so that even if the lower positioning portion 72C moves to the stage main body 61 at a slower speed than the initial speed, the imaging plate 10 is less likely to interfere strongly with the first direction positioning portion 72B, as described above.

[0254] Furthermore, the lower positioning portion 72C moves downward relative to the stage body 61 while the lower positioning portion 72C is moving upward relative to the stage body 61 or before starting its upward movement. Therefore, by moving the lower positioning portion 72C upward or downward at the beginning of its movement, tilt correction of the imaging plate 10 can be facilitated. By moving the lower positioning portion 72C downward during or at the beginning of its movement after the initial movement of the lower positioning portion, the imaging plate 10 can be moved along the second direction F2 between the first direction positioning portions 72A and 72B, making it less likely that the pair of first direction positioning portions 72A and 72B will sandwich the imaging plate 10 in a tilted state. For example, even if it becomes desirable to move the lower corner of the tilted imaging plate 10 downward to correct the tilt when the pair of first direction positioning portions 72A and 72B are sandwiching the imaging plate 10, the tilt correction can be smoothly performed by moving the lower positioning portion 72C downward.

[0255] Furthermore, when sub cam follower 587b comes into contact with sub cam surface 592f, it moves lower positioning portion 72C downward relative to stage main body 61. As a result, the direction in which sub cam surface 592f presses sub cam follower 587b approaches the direction in which sub cam follower 587b moves. Therefore, the force that moves stage 60 can smoothly push and move sub cam follower 587b, and lower positioning portion 72C can smoothly and temporarily move downward relative to stage 60. In other words, movement of stage 60 in one direction from set position P1 toward reading position P2 can move lower positioning portion 72C upward or downward relative to stage main body 61.

[0256] As explained in the above embodiment and modified examples, it is preferable that the timing at which the lower positioning unit moves upward to a position where it can position the imaging plate 10 in the vertical direction is after the left-right positioning has been completed. To achieve this, in this embodiment, the movement timing of the lower positioning unit is adjusted using a combination of cams and links. As a result, the lower positioning unit is moved after the left-right positioning, delaying the timing of the stage movement, and vertical positioning is achieved.

[0257] To make it difficult for the first direction positioning portions 72A, 72B to pinch the imaging plate 10 at an angle, it is preferable to reduce the coefficient of friction of the first direction positioning portions 72A, 72B with respect to the imaging plate 10. For example, the first direction positioning portions 72A, 72B may be formed from POM (polyacetal) or Teflon (registered trademark), or the surfaces that come into contact with the imaging plate 10 may be machined or polished.

[0258] The configurations described in the above embodiment and modifications can be combined as appropriate as long as they are not mutually contradictory.

[0259] <Additional Notes> The present specification and drawings disclose the following aspects.

[0260] A first aspect is a radiation image reading device that reads a radiation image from an imaging plate, the radiation image reading device comprising: a stage that holds the imaging plate; an excitation light source that irradiates the imaging plate held on the stage with excitation light; and a photodetector that detects emission light from the imaging plate in response to the excitation light. The stage includes: a stage body having a support surface that can come into surface contact with the back surface of the imaging plate; a first direction positioning mechanism that has a pair of first direction positioning members, at least one of which moves along a first direction as a movable first direction positioning member to sandwich the imaging plate on the support surface along the first direction; and a second direction positioning mechanism that has a lower positioning member that supports the imaging plate on the support surface from below in a second direction that intersects with the first direction and is closer to the direction of gravity than the first direction, and the lower positioning member moves along the second direction relative to the stage body.

[0261] According to this reading device, when at least one of the pair of first-direction positioning units moves along the first direction to sandwich the imaging plate on the support surface along the first direction, depending on the inclination of the imaging plate on the stage body, it is conceivable that the pair of first-direction positioning units will sandwich the imaging plate at an angle. By moving the lower positioning unit that supports the imaging plate on the support surface from below along the second direction, the imaging plate moves in the second direction between the pair of first-direction positioning units, making it less likely that the pair of first-direction positioning units will sandwich the imaging plate at an angle. This corrects the imaging plate to a normal position on the support surface, and the imaging plate can be held in the normal position.

[0262] A second aspect is the radiation image reading device according to the first aspect, wherein the lower positioning part moves along the second direction during at least a part of the period during which the first direction movable positioning part moves.

[0263] In this case, the imaging plate is more likely to move in the second direction while in contact with the first-direction movable positioning parts, making it less likely that the pair of first-direction positioning parts will clamp the imaging plate in an inclined position.

[0264] A third aspect is the radiation image reading device according to the first aspect, wherein the lower positioning part starts moving along the second direction before the start of the moving operation period of the first direction movable positioning part.

[0265] This makes it easier to correct the tilt of the imaging plate before the second direction positioning mechanism applies a clamping force to the imaging plate.

[0266] A fourth aspect is a radiological image reading device according to any one of the first to third aspects, wherein the first direction movable positioning portion has a plurality of first direction movable positioning surfaces that contact the imaging plate at spaced positions in the second direction.

[0267] In this case, any one of the plurality of first direction movable positioning surfaces can push the imaging plate along the second direction at a position that avoids the corners of the imaging plate, thereby correcting the tilt of the imaging plate.

[0268] A fifth aspect is a radiation image reading device according to any one of the first to fourth aspects, wherein the stage is capable of supporting imaging plates of a plurality of sizes, and the first direction movable positioning unit moves between a position where the largest imaging plate of the plurality of sizes can be sandwiched between the pair of first direction positioning units, and a position where the smallest imaging plate of the plurality of sizes can be sandwiched between the pair of first direction positioning units.

[0269] In this case, if the gap between the pair of first-direction positioning units is wide enough to sandwich the largest imaging plate among the imaging plates of multiple sizes, the smallest imaging plate will be prone to tilting when placed between them. In such a case, the imaging plate can be effectively corrected by moving the lower positioning units in the second direction to move the imaging plate in the second direction.

[0270] A sixth aspect is a radiological image reading device according to any one of the first to fifth aspects, wherein the lower positioning part stops relative to the stage body while the lower positioning part is moving upward relative to the stage body, or the lower positioning part moves at a speed slower than the initial speed at which the lower positioning part moves relative to the stage.

[0271] In this case, the lower positioning unit can be moved at a high speed in the initial stage of its movement to facilitate correcting tilt of the imaging plate. After the lower positioning unit has been moved at a high speed, the lower positioning unit can be stopped or its movement speed reduced midway through its movement to maintain a position where the imaging plate is less likely to interfere with the first-direction movable positioning unit.

[0272] A seventh aspect is a radiological image reading device according to any one of the first to sixth aspects, wherein the lower positioning part moves downward relative to the stage body while the lower positioning part is moving upward relative to the stage body or before starting to move upward.

[0273] In this case, the lower positioning parts can be moved downward during or before the upward movement of the lower positioning parts, making it easier to correct the tilt of the imaging plate. After the tilt of the imaging plate is corrected by the downward movement of the lower positioning parts, the imaging plate can be moved in the second direction between the first direction positioning parts, making it difficult for the pair of first direction positioning parts to pinch the imaging plate in a tilted state.

[0274] An eighth aspect is a radiological image reading device according to any one of the first to seventh aspects, wherein the second direction positioning mechanism has an upper positioning portion that faces the lower positioning portion in the second direction, and while the pair of first direction positioning portions sandwich the imaging plate in the first direction, the upper positioning portion and the lower positioning portion sandwich the imaging plate in the second direction.

[0275] In this case, after the tilt of the imaging plate is corrected by the pair of first direction positioning units, the upper positioning unit and the lower positioning unit sandwich the imaging plate in the second direction, thereby positioning the imaging plate in the second direction. When the pair of first direction positioning units corrects the tilt of the imaging plate, the upper positioning unit is less likely to interfere.

[0276] A ninth aspect is a radiological image reading device according to any one of the first to eighth aspects, wherein the pair of first direction positioning members clamp the imaging plate while applying the biasing force of an elastic member.

[0277] With this, in a state where the imaging plate is sandwiched between the pair of first direction positioning parts, the imaging plate can be moved in the second direction by moving the lower positioning part, thereby positioning it in the second direction.

[0278] A tenth aspect is a radiological image reading device according to any one of the first to ninth aspects, wherein the stage is positioned below the pair of first direction positioning portions and has an ejection guide surface that faces away from the support surface as it moves downward along the second direction, and the lower positioning portion moves in the second direction between a separated ejection position below the ejection guide surface and a clamping position above the ejection guide surface.

[0279] In this case, when the lower positioning portion is positioned for ejection, if the imaging plate falls due to gravity, it is guided by the ejection guide surface in a direction away from the support surface, and is easily ejected. By moving the lower positioning portion upward from the ejection guide surface, it is possible to support the imaging plate from below on the support surface.

[0280] An eleventh aspect is a radiation image reading device according to any one of the first to tenth aspects, further comprising a stage moving mechanism that moves the stage between a set position where the imaging plate is set relative to the stage and a read position where the photodetector reads the radiation image in response to excitation light from the excitation light source, and a positioning unit operating mechanism that causes the first direction positioning mechanism to perform a closing operation and the lower positioning unit of the second direction positioning mechanism to operate in conjunction with the stage moving mechanism moving the stage from the set position to the read position.

[0281] In this case, in accordance with the movement of the stage from the set position to the reading position, the first direction positioning mechanism can be caused to perform a closing operation and the lower positioning part of the second direction positioning mechanism can be operated.

[0282] A twelfth aspect is the radiological image reading device according to the eleventh aspect, wherein the positioning unit operating mechanism comprises a lower positioning unit operating mechanism that moves the lower positioning unit along the second direction in accordance with the movement of the stage from the set position to the reading position by the stage moving mechanism, and the lower positioning unit operating mechanism comprises a link mechanism including a plurality of links, any one of which has a cam follower, any other one of which is connected to the lower positioning unit, and at least one of which is supported swingably via a swing fulcrum, and a cam surface with which the cam follower comes into follower contact as the stage moves, causing the cam follower to displace in a direction intersecting the direction of movement of the stage, and the link mechanism transmits the displacement of the cam follower in the direction intersecting the direction of movement of the stage as a force that moves the lower positioning unit relative to the stage body.

[0283] This causes the cam surface to cause the cam follower to displace in a direction that intersects with the direction of stage movement, and the resulting displacement of the cam follower is converted by the link mechanism and transmitted as a force that moves the lower positioning part.

[0284] A thirteenth aspect is a radiological image reading device according to the twelfth aspect, wherein the lower positioning unit operating mechanism has a biasing unit that constantly applies an upward force to the lower positioning unit, and the biasing force of the biasing unit applies a force that presses the cam follower against the cam surface.

[0285] In this case, the cam follower is pressed against the cam surface by the biasing force of the biasing portion, so the cam follower can be positioned in a position corresponding to the cam surface. Depending on the state of restriction of the cam follower by the cam surface, the biasing portion can move the lower positioning portion upward.

[0286] A fourteenth aspect is a radiological image reading device according to the thirteenth aspect, wherein the lower positioning unit operating mechanism has a sub-cam surface located on the opposite side of the cam surface relative to the swing fulcrum, one of the plurality of links has a sub-cam follower located on the opposite side of the cam follower relative to the swing fulcrum, the sub-cam follower contacts the sub-cam surface on the opposite side of the swing fulcrum from the cam surface and the cam follower, and the link mechanism transmits the displacement of the sub-cam follower as a force that moves the lower positioning unit downward relative to the stage body.

[0287] This makes it easy to move the lower positioning part upward or downward relative to the stage body by moving the stage in one direction.

[0288] The above description is illustrative in all respects and is not intended to limit the scope of the present invention. It is understood that numerous variations not illustrated can be envisioned without departing from the scope of the present invention. [Explanation of symbols]

[0289] 10 Imaging Plate 10b back side 20, 520 Radiation image reading device 50 Stage movement mechanism 60 stages 61 Stage body 64F Support surface 68 Ejection guide 68g Discharge guide surface 70 First direction positioning mechanism 71 Second direction positioning mechanism 72A First direction positioning part (first direction movable positioning part) 72Af Positioning surface 72B First direction positioning part 72Baf, 72Bbf Positioning surface (first direction movable positioning surface) 72Bs spring 72C Lower positioning part 72Cf Positioning surface 72Cs spring 72D Upper positioning part 72Df Positioning surface 80 Positioning unit operating mechanism 84 Lower positioning unit operating mechanism 82f, 582f, 682f working surface 85 Link mechanism 86 Link 1 87 Second Link 87b Cam follower 89f, 589f, 689f cam surface 92 Excitation light source 94 Photodetector 587b Sub-cam follower 592f sub cam surface F1 1st direction F2 2nd direction P1 Set position P2 reading position P3 discharge position

Claims

1. A radiation image reading device for reading a radiation image from an imaging plate, comprising: a stage for holding the imaging plate; an excitation light source that irradiates the imaging plate held on the stage with excitation light; a photodetector for detecting luminescence light from the imaging plate due to the excitation light; Equipped with The stage is a stage body having a support surface that can come into surface contact with the rear surface of the imaging plate; a first direction positioning mechanism including a pair of first direction positioning parts, at least one of which moves along a first direction as a first direction movable positioning part to sandwich the imaging plate on the support surface along the first direction; a second direction positioning mechanism including a lower positioning unit that supports the imaging plate on the support surface from below in a second direction that intersects with the first direction and is closer to a gravity direction than the first direction, and the lower positioning unit moves along the second direction relative to the stage body; Including, a stage moving mechanism that moves the stage between a set position where the imaging plate is set relative to the stage and a read position where the photodetector reads the radiation image in response to excitation light from the excitation light source; a positioning unit operating mechanism that causes the first direction positioning mechanism to perform a closing operation and the lower positioning unit of the second direction positioning mechanism to operate in accordance with the movement of the stage from the set position to the reading position by the stage moving mechanism; The radiation image reading device further comprises:

2. A radiation image reading device according to claim 1, the positioning unit operating mechanism includes a lower positioning unit operating mechanism that moves the lower positioning unit along the second direction in accordance with the movement of the stage from the set position to the reading position by the stage moving mechanism, The lower positioning unit operating mechanism is a link mechanism including a plurality of links, any one of the plurality of links having a cam follower portion, any other one of the plurality of links being connected to the lower positioning portion, and at least one of the plurality of links being swingably supported via a swing fulcrum; a cam surface that the cam follower comes into follower contact with as the stage moves, causing the cam follower to displace in a direction intersecting the direction of movement of the stage; and The link mechanism transmits the displacement of the cam follower in a direction intersecting the moving direction of the stage as a force that moves the lower positioning part relative to the stage body.

3. A radiation image reading device according to claim 2, the lower positioning unit operating mechanism has a biasing unit that constantly applies an upward force to the lower positioning unit, The biasing force of the biasing portion acts to press the cam follower against the cam surface.

4. A radiation image reading device according to claim 3, The lower positioning unit operating mechanism is a sub-cam surface located on the opposite side of the cam surface with respect to the swing fulcrum, any one of the plurality of links has a sub-cam follower located on the opposite side of the cam follower with respect to the swing fulcrum, the sub-cam follower contacts the sub-cam surface on the side opposite to the cam surface and the cam follower with respect to the swing fulcrum, The link mechanism transmits the displacement of the sub-cam follower as a force that moves the lower positioning portion downward relative to the stage body.

5. A radiation image reading device according to claim 1, a radiation image reading device, wherein the lower positioning unit stops relative to the stage body while moving upward relative to the stage body, or moves at a speed slower than the initial speed at which the lower positioning unit moves relative to the stage;

6. A radiation image reading device according to claim 1, A radiation image reading device, wherein the lower positioning unit moves downward relative to the stage body while the lower positioning unit is moving upward relative to the stage body or before the lower positioning unit starts to move upward.

7. A radiation image reading device according to claim 1, the stage is positioned below the pair of first direction positioning units and has a discharge guide surface that faces in a direction away from the support surface as it extends downward along the second direction, The lower positioning portion moves in the second direction between a separated discharge position below the discharge guide surface and a clamping position above the discharge guide surface.

Images