Medical imaging diagnostic equipment and bed equipment

Abstract

To measure the weight of a subject by a bed apparatus.SOLUTION: A medical image diagnostic apparatus according to an embodiment comprises: a top plate; a lifting mechanism; a power unit; a power control unit; and an estimation unit. A subject is placed on the top plate. The lifting mechanism lifts or lowers the top plate. The power unit gives the power of holding or lifting / lowering the top plate to the lifting mechanism. The power control unit controls the power unit such that the top plate is lowered according to the weight of the subject placed on the top plate. The estimation unit estimates an estimated weight being the weight of the subject on the basis of a displacement amount of a height position of the top plate under the control.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The embodiments disclosed in this specification and the drawings relate to a medical image diagnostic apparatus and a bed apparatus. [Background technology]

[0002] Medical imaging diagnostic devices provide users with information useful for diagnosis and treatment by acquiring medical images by capturing images of the inside of a subject. Some imaging conditions for medical imaging diagnostic devices are determined based on the weight of the subject, such as the amount of contrast agent administered to the subject and the X-ray dose. Methods for acquiring the weight of the subject include using a scale separate from the medical imaging diagnostic device and having the subject self-report the weight. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2012-125305 [Patent Document 2] Japanese Patent Application Laid-Open No. 2010-167189 Summary of the Invention [Problem to be solved by the invention]

[0004] One of the problems to be solved by the embodiments disclosed in this specification and the drawings is to measure the weight of a subject using a bed apparatus. However, the problems to be solved by the embodiments disclosed in this specification and the drawings are not limited to the above problem. Problems corresponding to the configurations shown in the embodiments described below can also be positioned as other problems. [Means for solving the problem]

[0005] The medical image diagnostic apparatus according to this embodiment includes a tabletop, a lifting mechanism, a power unit, a power control unit, and an estimation unit. A subject is placed on the tabletop. The lifting mechanism raises and lowers the tabletop. The power unit provides the lifting mechanism with power to hold or raise and lower the tabletop. The power control unit controls the power unit so that the tabletop descends in accordance with the weight of the subject placed on the tabletop. The estimation unit estimates an estimated weight, which is the weight of the subject, based on the amount of displacement of the height position of the tabletop under the control. [Brief explanation of the drawings]

[0006] [Figure 1] FIG. 1 is a block diagram showing an example of the configuration of an X-ray CT apparatus according to the first embodiment. [Figure 2] FIG. 2 is a block diagram showing an example of the configuration of a control device according to the first embodiment. [Figure 3] FIG. 3 is a block diagram showing an example of the configuration of a bed apparatus according to the first embodiment. [Figure 4] FIG. 4 is a block diagram showing an example of the configuration of a support frame according to the first embodiment. [Figure 5] FIG. 5 is a schematic diagram for explaining an example of a position correction amount at the time of shooting according to the first embodiment. [Figure 6] FIG. 6 is a flowchart showing an example of processing executed by a processing circuit of the X-ray CT apparatus according to the first embodiment. [Figure 7] FIG. 7 is a graph showing an example of a change over time in the height position of the tabletop according to the first embodiment. [Figure 8] FIG. 8 is a diagram for explaining an example of a lookup table according to the first embodiment. [Figure 9] FIG. 9 is a block diagram showing an example of the configuration of a control device according to the second embodiment. [Figure 10] FIG. 10 is a block diagram showing an example of the configuration of a bed apparatus according to the second embodiment. [Figure 11] FIG. 11 is a flowchart showing an example of processing executed by a processing circuit of the X-ray CT apparatus according to the second embodiment. [Figure 12]FIG. 12 is a graph showing an example of temporal changes in the height position of the tabletop and the output of the bed driving device according to the second embodiment. [Figure 13] FIG. 13 is a diagram for explaining an example of a lookup table according to the second embodiment. [Figure 14] FIG. 14 is a flowchart showing an example of processing executed by a processing circuit of the X-ray CT apparatus according to the third embodiment. [Figure 15] FIG. 15 is a graph showing an example of temporal changes in the height position of the tabletop and the output of the bed driving device according to the third embodiment. [Figure 16] FIG. 16 is a block diagram showing an example of the configuration of a bed apparatus according to a fourth embodiment. [Figure 17] FIG. 17 is a block diagram showing an example of the configuration of a bed apparatus according to the fifth embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0007] Hereinafter, a medical image diagnostic apparatus and a bed apparatus according to each embodiment will be described with reference to the drawings.

[0008] The medical image diagnostic apparatus is a single modality such as an X-ray CT (Computed Tomography) apparatus, an MRI (Magnetic Resonance Imaging) apparatus, a PET (Positron Emission Tomography) apparatus, or a SPECT (Single Photon Emission Computed Tomography) apparatus. Alternatively, the medical image diagnostic apparatus may be a combined modality such as a PET-CT apparatus, a SPECT-CT apparatus, and a PET-MR apparatus. In the following description, the medical image diagnostic apparatus according to each embodiment will be described as an X-ray CT apparatus, but each embodiment is not limited to an X-ray CT apparatus and can be similarly implemented by the various medical image diagnostic apparatuses described above.

[0009] (First embodiment) A first embodiment will be described. The bed apparatus 30 according to this embodiment includes a tabletop 31 on which a subject is placed, and an elastic body 80 that is disposed between the tabletop 31 and the floor on which the bed apparatus 30 is placed and that is elastically deformed when pressed by the tabletop 31. In this embodiment, when a subject P is placed on the tabletop 31, which is held in place by the elastic force generated in the elastically deformed elastic body 80, the tabletop 31 is controlled to descend until the gravity acting on the subject P and the elastic force generated in the elastic body 80 are balanced. An example will be described in which the amount of displacement between the height position of the tabletop 31 before the control and the height position of the tabletop 31 after the balance is achieved is measured, and the weight of the subject P placed on the tabletop 31 is estimated by referring to a lookup table prepared in advance using the measured amount of displacement. The bed apparatus 30, the tabletop 31, and the elastic body 80 will be described in more detail below.

[0010] FIG. 1 is a block diagram showing an example of the configuration of an X-ray CT apparatus 1 according to the first embodiment. The X-ray CT apparatus 1 includes, for example, a gantry 10, a bed 30, and a console 40. For convenience of explanation, FIG. 1 shows both a view of the gantry 10 from the Z-axis direction and a view from the X-axis direction, but in reality, there is only one gantry 10. In this embodiment, the rotation axis of the rotating frame 17 in a non-tilted state or the longitudinal direction of the tabletop 31 of the bed 30 is defined as the Z-axis direction, an axis perpendicular to the Z-axis direction and horizontal to the floor surface is defined as the X-axis direction, and a direction perpendicular to the Z-axis direction and perpendicular to the floor surface is defined as the Y-axis direction.

[0011] The gantry device 10 includes an X-ray tube 11, a wedge 12, a collimator 13, an X-ray high voltage device 14, an X-ray detector 15, a DAS (Data Acquisition System) 16, a rotating frame 17, and a control device 18.

[0012] The X-ray tube 11 generates X-rays by irradiating thermoelectrons from a cathode (filament) to an anode (target) when a high voltage is applied from the X-ray high voltage device 14. The X-ray tube 11 includes a vacuum tube. For example, the X-ray tube 11 is a rotating anode type X-ray tube that generates X-rays by irradiating a rotating anode with thermoelectrons.

[0013] The wedge 12 is a filter for adjusting the amount of X-rays irradiated from the X-ray tube 11 to the subject P. Specifically, the wedge 12 is a filter that transmits and attenuates the X-rays irradiated from the X-ray tube 11 so that the X-rays irradiated from the X-ray tube 11 to the subject P have a predetermined distribution. For example, the wedge 12 is a wedge filter or a bow-tie filter, which is a filter made of processed aluminum so as to have a predetermined target angle and a predetermined thickness.

[0014] The collimator 13 is a lead plate or the like for narrowing down the irradiation range of the X-rays transmitted through the wedge 12, and a slit is formed by combining a plurality of lead plates or the like. The collimator 13 may also be called an X-ray aperture.

[0015] X-ray high voltage device 14 has electrical circuits such as a transformer and a rectifier, and includes a high-voltage generator having the function of generating a high voltage to be applied to X-ray tube 11, and an X-ray control device that controls the output voltage according to the amount of X-rays irradiated by X-ray tube 11. The high-voltage generator may be of a transformer type or an inverter type. X-ray high voltage device 14 may be provided on rotating frame 17, which will be described later, or on the fixed frame (not shown) side of gantry device 10. The fixed frame is a frame that rotatably supports rotating frame 17. X-ray high voltage device 14 is an example of an X-ray high voltage unit.

[0016] The X-ray detector 15 detects X-rays emitted from the X-ray tube 11 and passing through the subject P, and outputs an electrical signal corresponding to the X-ray dose to the DAS 16. The X-ray detector 15 has, for example, a plurality of X-ray detection element rows, in which a plurality of X-ray detection elements are arranged in the channel direction along an arc centered on the focal point of the X-ray tube 11. The X-ray detector 15 has, for example, a structure in which a plurality of X-ray detection element rows, in which a plurality of X-ray detection elements are arranged in the channel direction, are arranged in the slice direction (column direction, row direction). The X-ray detector 15 is, for example, an indirect conversion type detector having a grid, a scintillator array, and a photosensor array.

[0017] The scintillator array has a plurality of scintillators, each of which has a scintillator crystal that outputs light in an amount of photons corresponding to the amount of incident X-rays.

[0018] The grid is placed on the X-ray incident side of the scintillator array and has an X-ray shielding plate that absorbs scattered X-rays. The grid is sometimes called a collimator (one-dimensional collimator or two-dimensional collimator).

[0019] The photosensor array has a function of converting the amount of light from the scintillator into an electrical signal according to the amount of light, and includes photosensors such as photodiodes and photomultiplier tubes.

[0020] The X-ray detector 15 may be a direct conversion type detector having a semiconductor element that converts incident X-rays into an electrical signal. The X-ray detector 15 is an example of an X-ray detection unit.

[0021] The DAS 16 has an amplifier that amplifies the electrical signals output from each X-ray detection element of the X-ray detector 15 and an A / D converter that converts the electrical signals into digital signals, and generates detection data. The detection data generated by the DAS 16 is transferred to the console device 40. The DAS 16 is also an example of a data acquisition unit.

[0022] The rotating frame 17 is an annular frame that supports the X-ray tube 11 and the X-ray detector 15 so as to face each other, and rotates the X-ray tube 11 and the X-ray detector 15 using a control device 18, which will be described later. In addition to the X-ray tube 11 and the X-ray detector 15, the rotating frame 17 also supports the X-ray high voltage device 14 and the DAS 16. Furthermore, the rotating frame 17 can also support various components not shown in Fig. 1. Hereinafter, the rotating frame 17 and the parts of the gantry device 10 that rotate together with the rotating frame 17 will also be referred to as a rotating part.

[0023] The detection data generated by the DAS 16 is transmitted by optical communication from a transmitter having a light emitting diode (LED) provided on the rotating frame 17 to a receiver having a photodiode provided on a non-rotating part of the gantry device 10, and then transferred to the console device 40 (described later). Non-contact data transfer may also be employed. The rotating frame 17 is an example of a rotating part.

[0024] The configuration of the control device 18 will be described with reference to Fig. 2. Fig. 2 is a block diagram showing an example of the configuration of the control device 18 according to this embodiment.

[0025] The control device 18 includes, for example, a memory 181, a drive mechanism (not shown) such as a motor and an actuator, and a processing circuit 182 including a CPU (Central Processing Unit). The control device 18 receives input signals from an input interface 43 (described later) and a processing circuit 50 attached to the console device 40 or the gantry device 10, and controls the operation of the gantry device 10 and the bed 30. For example, the control device 18 receives input signals and controls the rotation of the rotating frame 17, the tilt of the gantry device 10, and the operation of the bed 30 and the tabletop 31. The control of tilting the gantry device 10 is realized by the control device 18 rotating the rotating frame 17 around an axis parallel to the X-axis direction based on inclination angle (tilt angle) information input via the input interface 43 attached to the gantry device 10. The control device 18 may be provided in the gantry device 10 or the console device 40.

[0026] The memory 181 is realized by, for example, a semiconductor memory device such as a RAM (Random Access Memory), a flash memory, a hard disk, an optical disk, etc. The memory 181 stores, for example, a contact position H1 (described later), a lower limit position H4 that is the lower limit of the height position of the top 31, weight data associated with accessories (described later), a lookup table used to estimate the weight of the subject P placed on the top 31 (described later), a lookup table and function that associate the weight of the top 31, the weight of the subject P, and an appropriate amount of contrast agent, data on the cross-sectional shape of the subject P according to the weight of the subject P, and data on the imaging range (Field Of View: FOV) used when capturing a positioning image and setting imaging conditions for the main imaging. These data may be stored in an external memory with which the control device 18 can communicate, instead of (or in addition to) the memory 181. The external memory is, for example, the memory 41.

[0027] The processing circuitry 182 controls the operations of the gantry device 10 and the bed device 30. The power control function 182a, braking control function 182b, necessity determination function 182c, height acquisition function 182d, accessory weight acquisition function 182e, estimation function 182f, calculation function 182g, shape estimation function 182h, and position correction function 182i of the processing circuitry 182 are recorded in the memory 181 in the form of computer-executable programs. The processing circuitry 182 realizes the functions corresponding to each program by reading and executing the programs from the memory 181. In other words, the processing circuitry 182 in a state in which each program has been read has each function shown in the processing circuitry 182 in FIG. 2. The processing circuitry 182 is realized by, for example, a processor. The processing circuitry 182 is also an example of a processing unit.

[0028] 2, the processing circuit 182 is implemented by a single processor, and the processing functions performed by the power control function 182a, braking control function 182b, necessity determination function 182c, height acquisition function 182d, accessory weight acquisition function 182e, estimation function 182f, calculation function 182g, shape estimation function 182h, and position correction function 182i of the processing circuit 182 are realized. However, the processing circuit 182 may be configured by combining multiple independent processors, and each processor may execute a program to realize each function of the processing circuit 182. Furthermore, while FIG. 2 illustrates the configuration in which a single memory 181 stores programs corresponding to each processing function of the processing circuit 182, multiple memories 181 may be distributed and the processing circuit 182 may read corresponding programs from each memory 181.

[0029] The term "processor" used in the above description refers to a circuit such as a CPU (Central Processing Unit), a GPU (Graphics Processing Unit), an Application Specific Integrated Circuit (ASIC), a programmable logic device (e.g., a Simple Programmable Logic Device (SPLD), a Complex Programmable Logic Device (CPLD), or a Field Programmable Gate Array (FPGA)). When the processor is, for example, a CPU, the processor realizes a function by reading and executing a program stored in memory 181. On the other hand, when the processor is an ASIC, instead of storing a program in memory 181, the function is directly incorporated as a logic circuit within the circuit of the processor.

[0030] The power control function 182a outputs a command signal to the bed driving device 34, which will be described later, to control the operation of raising and lowering the tabletop 31. The control details of the bed driving device 34 by the power control function 182a will be described later. The power control function 182a is an example of a power control unit.

[0031] The braking control function 182b outputs an instruction signal to the braking device 38, which will be described later, to perform on / off control of the braking device 38. The control performed by the braking control function 182b on the braking device 38 will be described later. The braking control function 182b is an example of a braking control unit.

[0032] The necessity determination function 182c determines whether or not to execute weight estimation of the subject P based on an input operation received from a user via the input interface 43, which will be described later. The necessity determination function 182c is an example of a necessity determination unit.

[0033] For example, the necessity determination function 182c causes a display control function 56 (described later) to display a GUI (Graphical User Interface) screen on a display 42 (described later) that receives from the user whether or not weight estimation of the subject P is necessary. Thereafter, the necessity determination function 182c may receive the user's determination on whether or not weight estimation of the subject P is necessary via the GUI screen. Furthermore, the necessity determination function 182c may receive the user's determination on whether or not weight estimation of the subject P is necessary via an input interface (such as an input interface 43 (described later)) such as a button provided on the gantry device 10, the bed device 30, and the console device 40 (described later).

[0034] The necessity determination function 182c may also determine whether to perform weight estimation of the subject P, which will be described later, based on information about the subject P from a past examination. The necessity determination function 182c receives, for example, information about the subject P from a past examination from a radiology information system (RIS). The information about the subject P from the past examination is, for example, the date and time of the past examination and the weight of the subject P at the time of the past examination. For example, the necessity determination function 182c determines that it is necessary to perform weight estimation of the subject P if the date and time of the past examination is a certain period before the date and time of the current examination. On the other hand, for example, the necessity determination function 182c determines that it is not necessary to perform weight estimation of the subject P if the date and time of the past examination is within a certain period of time before the current date and time. The necessity determination function 182c may also receive information about the certain period, which is arbitrarily set by the user, such as three months or six months, via the input interface 43, which will be described later.

[0035] The height acquisition function 182d acquires the height position, which is the position of the tabletop 31 in the Y direction, from the encoder 81, which will be described later, and outputs it to the memory 181. The height acquisition function 182d may also output the amount of displacement from a reference height position of the tabletop 31 to the memory 181. The height acquisition function 182d is an example of a height acquisition unit.

[0036] The accessory weight acquisition function 182e derives the weight of accessories placed on the tabletop 31 in addition to the subject P and outputs the weight of the accessories to the memory 181. Examples of accessories include a syringe pump, a drain bag, a feces bag, a bedside monitor, a medical oxygen cylinder, a backboard, an infusion solution, and a tray. For example, the accessory weight acquisition function 182e acquires an image of an area including the subject P and the accessories from the camera 20 (described later) when the subject P is placed on the tabletop 31. The accessory weight acquisition function 182e then detects the accessories from the image and reads out the weights corresponding to each detected accessory from a lookup table stored in the memory 181. The accessory weight acquisition function 182e then outputs the total weight of all detected accessories to the memory 181. The user may input the weight of the accessories via the input interface 43 (described later). The accessory weight acquisition function 182e is an example of an accessory weight acquisition unit.

[0037] The estimation function 182f estimates the weight of the subject P placed on the top board 31. The estimation function 182f outputs the weight (estimated weight) of the subject P placed on the top board 31 to the memory 181, for example, using a lookup table in which the displacement amount of the height position of the top board 31 stored in the memory 181 is associated with a plurality of weight values. The estimation function 182f is also an example of an estimation unit.

[0038] In addition, cases in which the estimated weight obtained by the estimation function 182f does not match the actual weight of the subject P may occur when accessories are placed on the top plate 31 after the subject P is placed on the top plate 31, or when the subject P with accessories attached is placed on the top plate 31.

[0039] The method for dealing with this case will be described below. The estimation function 182f reads the total weight of the accessories acquired by the accessory weight acquisition function 182e from the memory 181. Then, the estimation function 182f performs post-processing to subtract the total weight of the accessories from the estimated weight. Then, the estimation function 182f updates the estimated weight to the weight after the post-processing.

[0040] The calculation function 182g acquires the estimated weight from the memory 181 and calculates, from the estimated weight, an appropriate amount of contrast agent to be administered to the subject P. For example, the calculation function 182g reads out from the memory 181 a lookup table and a function that associate the estimated weight of the subject P with appropriate amounts of contrast agent, and calculates an appropriate amount of contrast agent according to the weight of the subject P. The calculation function 182g outputs the appropriate value to the memory 181. The calculation function 182g is an example of a calculation unit.

[0041] The shape estimation function 182h obtains the estimated weight from the memory 181 and obtains the height, age, and sex of the subject P from the RIS, and estimates the shape of the subject P. The estimation function 182f estimates the cross-sectional shape of the subject P by, for example, reading out from the memory 181 the cross-sectional shape of the subject P corresponding to information combining the estimated weight, height, age, and sex of the subject P. The shape estimation function 182h outputs the cross-sectional shape (estimated cross-section) to the memory 181. The shape estimation function 182h is an example of a shape estimation unit.

[0042] The position correction function 182i acquires the estimated cross section from the memory 181 and corrects the height position of the top 31 during the capture of the positioning image and the actual capture. FIG. 5 is a diagram showing an example of the position correction amount in this embodiment. The left diagram of FIG. 5 shows an example in which the height position of the top 31 is set so that the height positions of the center of gravity of the cross section of the subject P prepared as the initial conditions when setting the imaging conditions and the center of gravity of the FOV coincide. The right diagram of FIG. 5 shows an example in which the height position of the top 31 is set so that the height positions of the center of gravity of the estimated cross section and the center of gravity of the FOV coincide. If there is a discrepancy in the width in the Y direction between the cross section of the subject P prepared as the initial conditions when setting the imaging conditions and the estimated cross section, the height positions of the center of gravity of the cross section of the subject P and the center of gravity of the FOV will be misaligned unless the height position of the top 31 is corrected. Therefore, the position correction function 182i calculates the position correction amount of the top 31 so that the height positions of the center of gravity of the estimated cross section and the center of gravity of the FOV coincide. Thereafter, the position correction function 182i outputs a position correction signal for moving the height position of the tabletop 31 according to the position correction amount to the bed driving device 34. The position correction function 182i is an example of a position correction unit.

[0043] The camera 20 acquires an image capturing the tabletop 31 and the subject P placed on the tabletop 31. The camera 20 is provided, for example, above the tabletop 31. The camera 20 may be attached, for example, to the side of the gantry device 10 on the side where the bed device 30 is installed, on the ceiling of the room where the X-ray CT device 1 is installed, or near the bed device 30. The camera 20 may include multiple cameras.

[0044] Next, the configuration of the bed apparatus 30 will be described with reference to Figures 3 and 4. Figure 3 is a schematic side view of the bed apparatus 30 according to this embodiment, as viewed from the -X direction. Note that the housing of the bed apparatus 30 is not shown in Figure 3. Figure 4 is a schematic side view of the support frame 32 according to this embodiment, as viewed from the +Y direction.

[0045] The bed device 30 is a device on which a subject P to be imaged is placed and moved. The bed device 30 includes, for example, a tabletop 31, a support frame 32, a support base 33, a bed driving device 34, and a sensor 35, as shown in FIG.

[0046] The top board 31 is a board on which the subject P is placed. The top board 31 is provided on the upper surface of the support frame 32. The top board 31 is made of a material with a relatively high X-ray transmittance, such as urethane foam or carbon.

[0047] The support frame 32 is a frame-like frame that supports the tabletop 31 so that it can slide in the Z direction (the long axis direction of the tabletop 31). As shown in FIG. 4, for example, the support frame 32 has guide rails 321 that guide the tabletop 31 in the Z direction, and a tabletop drive device (not shown) for sliding the tabletop 31. The guide rails 321 are provided on a pair of frames that are the long sides of the support frame 32. The tabletop drive device receives an operation instruction signal from the control device 18 and realizes the sliding movement of the tabletop 31 along the guide rails 321. The support frame 32 may be, for example, a pair of beam-like frames to which the guide rails 321 are attached.

[0048] The support base 33 is a support mechanism that enables the top board 31 and the support frame 32 to move in the Y direction (vertical direction). The support base 33 has, for example, an X link 71 and a base 72, as shown in FIG.

[0049] The X link 71 is a pair of links pivoted in an X shape and connected to the support frame 32 and the base 72. The X link 71 has, for example, a movable link 711 and a fixed link 712. The movable link 711 and the fixed link 712 are provided so as to be rotatable around a fulcrum 73. Although only one X link 71 is shown in FIG. 3, there is another one in the +X direction. The X link 71 is also an example of a lifting mechanism.

[0050] The movable link 711 and the fixed link 712 are each formed, for example, by a pair of plate-like metal plates having approximately the same length. Furthermore, the distance between the end 715 of the movable link 711 on the base 72 side and the fulcrum 73, the distance between the end 716 of the movable link 711 on the support frame 32 side and the fulcrum 73, the distance between the end 713 of the fixed link 712 on the base 72 side and the fulcrum 73, and the distance between the end 714 of the fixed link 712 on the support frame 32 side and the fulcrum 73 are designed to be, for example, approximately the same length. The ends 714 and 716 are examples of ends connected to the tabletop, and the ends 713 and 715 are examples of ends opposite the end connected to the tabletop.

[0051] An end 713 of the fixed link 712 on the base 72 side is fixed to the base 72. The end 713 may be fixed, for example, by a fastener or the like, or by being fitted into a recess provided in the base 72. An end 714 of the fixed link 712 on the support frame 32 side is fixed to the support frame 32. The end 714 is fixed, for example, by a fastener or the like to a first link 76 between the rollers 74 provided on the guide rail 321. The end 714 may be fixed, for example, by a fastener or the like to the roller 74, or by being fitted into a recess provided in the support frame 32.

[0052] An end 715 of the movable link 711 on the base 72 side is connected to the base 72 so as to be slidable in the Z direction. The end 715 is connected to, for example, a nut 37. An end 716 of the movable link 711 on the support frame 32 side is connected to, for example, a second link 77 between rollers 75 provided on the guide rail 321 and slidable in the Z direction. The end 716 may be fixed to the rollers 75 with a fastener or the like, or may be fixed by being fitted into a recess provided in the support frame 32, for example.

[0053] The bed driving device 34 is a device that outputs power to move the tabletop 31 on which the subject P is placed in the Y direction (a direction perpendicular to the tabletop 31). The bed driving device 34 is, for example, a motor and an actuator. The bed driving device 34 outputs power in response to a signal from the control device 18, for example. The bed driving device 34 is also an example of a power unit.

[0054] One end of the lead screw 36 is connected to the drive shaft of the bed drive device 34, and the lead screw 36 rotates in conjunction with the rotation of the bed drive device 34 about the drive shaft. The lead screw 36 passes through a nut 37 and a brake device 38.

[0055] The nut 37 has a through hole with a thread groove formed therein that screws onto the threads of the lead screw 36. The nut 37 slides in the Z direction in conjunction with the rotation of the lead screw 36. For example, the nut 37 slides in the +Z direction when the lead screw 36 rotates in the forward direction, and slides in the -Z direction when the lead screw 36 rotates in the reverse direction.

[0056] As the nut 37 slides in the +Z direction, the end 715 is pressed against the nut 37 in the +Z direction, the movable link 711 and the fixed link 712 move closer to each other in the Z direction, and the top 31 and the support frame 32 move upward. As the nut 37 slides in the -Z direction, the end 715 is released from the pressure in the +Z direction, and the weight of the top 31 and the subject P placed on the top 31 causes the movable link 711 and the fixed link 712 to move apart in the Z direction, and the top 31 and the support frame 32 move downward.

[0057] When the bed driving device 34 receives an OFF control signal from the control device 18, it lowers the tabletop 31 and the support frame 32 by gravity according to the weight of the tabletop 31 and the subject P placed on the tabletop 31. For example, when the table driving device 34 is in the OFF state, the driving force shaft of the tabletop driving device 34 rotates in conjunction with the reverse rotation of the lead screw 36 that accompanies the sliding of the nut 37 in the −Z direction due to gravity acting on the tabletop 31 and the subject P placed on the tabletop 31.

[0058] The braking device 38 is a braking device that suppresses rotation of the lead screw 36 in response to a control signal from the control device 18. The braking device 38 is provided, for example, at one end of the lead screw 36. The braking device 38 is, for example, a brake such as a friction brake or an electric brake. Note that the braking device 38 may also be a brake provided inside the bed driving device 34. The braking device 38 is also an example of a braking unit.

[0059] For example, if the braking device 38 is a friction brake, the braking device 38 has a brake that restricts rotation of the lead screw 36 and an operating mechanism that supports the brake so that the brake can move toward or away from the lead screw 36. The braking device 38 is controlled to be turned on and off by a signal received from, for example, the control device 18. For example, when the braking device 38 receives an on signal from the control device 18, the braking device 38 turns on, the brake presses against the lead screw 36, and the lead screw 36 is fixed. This fixes the position of the nut 37, and the height position of the top plate 31 is maintained. For example, when the braking device 38 receives an off signal from the control device 18, the braking device 38 turns off, the brake moves away from the lead screw 36, and the lead screw 36 is released. As a result, the top 31 is raised and lowered in accordance with the power of the bed driving device 34 and the weight of the top 31 and the subject P placed on the top 31.

[0060] The bed driving device 34 is controlled so as to maintain the height position of the tabletop 31 on which the subject P is placed, even if the braking device 38 is suddenly turned off due to a malfunction or the like. For example, the bed driving device 34 outputs power to maintain the height position of the tabletop 31 on which the subject P is placed, even when the braking device 38 is on. Therefore, the bed driving device 34 can maintain the height position of the tabletop 31 even when the braking device 38 is switched from on to off.

[0061] The elastic body 80 has an end 802 fixed to the base 72, and the other end 801 is disposed in the +Y direction as viewed from the end 802. The elastic body 80 includes, for example, a helical spring, an air spring, and rubber. When the top 31 is located at a position lower than the height (contact position H1) at which the end 802 contacts the surface (back surface) of the top 31 opposite the surface on which the subject P is placed (contact position H1), the elastic body 80 elastically deforms and contracts. When the top 31 is raised in this state with the elastic body 80 elastically deformed, the elastic force of the elastic body 80 is obtained in addition to the power output by the bed drive device 34. In this way, the elastic body 80 serves as an auxiliary power for raising the top 31 from a position lower than the contact position H1. Although not shown, the elastic body 80 may have an end 801 fixed to the back surface of the top 31, and the other end 802 disposed in the -Y direction as viewed from the end 801.

[0062] The encoder 81 detects the height position of the tabletop 31. The encoder 81 may also detect the amount of displacement from a reference height position. Furthermore, the encoder 81 may detect that the height position of the tabletop 31, which has been stationary, has moved by more than a certain value. The encoder 81 is, for example, a position detector such as a rotary encoder attached to the tabletop 31. The encoder 81 may be attached to the support frame 32, the guide rail 321, etc., and may detect a calibrated value as the height position.

[0063] 1 again, the configuration of the console device 40 will be described. The console device 40 has a memory 41, a display 42, an input interface 43, and a processing circuit 50. In the embodiment, the console device 40 is described as being separate from the gantry device 10, but the gantry device 10 may include the console device 40 or some of the components of the console device 40. Furthermore, the bed device 30 may include the console device 40 or some of the components of the console device 40.

[0064] The memory 41 is realized by, for example, a semiconductor memory element such as RAM (flash memory), a hard disk, an optical disk, etc. The memory 41 stores, for example, detection data, projection data, reconstructed images, CT images, etc. These data may be stored in an external memory with which the X-ray CT apparatus 1 can communicate, instead of (or in addition to) the memory 41. The external memory is controlled by, for example, a cloud server that manages the external memory, by the cloud server accepting a read / write request. The memory 41 is also an example of a storage unit.

[0065] The display 42 displays various types of information. For example, the display 42 outputs medical images such as CT images generated by the processing circuitry 50, and a GUI for receiving various operations from the user. For example, the display 42 is a liquid crystal display or a CRT (Cathode Ray Tube) display. The display 42 is an example of a display unit. The display 42 may be a desktop type, or may be configured as a tablet terminal or the like capable of wireless communication with the console device 40 main body.

[0066] The input interface 43 accepts various input operations from the user, converts the accepted input operations into electrical signals, and outputs the electrical signals to the processing circuitry 50. For example, the input interface 43 accepts from the user the acquisition conditions for acquiring projection data, the reconstruction conditions for reconstructing CT images, the image processing conditions for generating post-processed images from CT images, and whether weight estimation (described later) is necessary. For example, the input interface 43 is realized by a mouse, a keyboard, a trackball, a switch, a button, a joystick, or the like. The input interface 43 is an example of an input unit. The input interface 43 may be provided in the gantry device 10 and the bed device 30. The input interface 43 may also be configured by a tablet terminal or the like capable of wireless communication with the console device 40 main body.

[0067] The processing circuitry 50 controls the overall operation of the X-ray CT apparatus 1. The system control function 51, pre-processing function 52, reconstruction processing function 53, image processing function 54, scan control function 55, and display control function 56 of the processing circuitry 50 are recorded in the memory 41 in the form of programs executable by a computer. The processing circuitry 50 realizes the functions corresponding to each program by reading and executing the programs from the memory 41. In other words, the processing circuitry 50 in a state in which each program has been read will have each function shown in the processing circuitry 50 in FIG. 1. The processing circuitry 50 is realized by, for example, a processor. The processing circuitry 50 is also an example of a processing unit.

[0068] 1, the processing circuit 50 is implemented by a single processor, with the processing functions being performed by the system control function 51, preprocessing function 52, reconstruction processing function 53, image processing function 54, scan control function 55, and display control function 56 of the processing circuit 50. However, the processing circuit 50 may be implemented by combining multiple independent processors, with each processor executing a program to implement each function of the processing circuit 50. Furthermore, although FIG. 1 has been described as a single memory 41 storing programs corresponding to each processing function of the processing circuit 50, multiple memories 41 may be distributed and the processing circuit 50 may read corresponding programs from individual memories 41.

[0069] The system control function 51 controls various functions of the processing circuit 50 based on input operations received from a user via the input interface 43. The system control function 51 is an example of a system control unit.

[0070] The pre-processing function 52 generates data by performing pre-processing such as logarithmic conversion, offset correction, inter-channel sensitivity correction, and beam hardening correction on the detection data output from the DAS 16. Note that the data before pre-processing (detection data) and the data after pre-processing are sometimes collectively referred to as projection data. The pre-processing function 52 is an example of a pre-processing unit.

[0071] The reconstruction processing function 53 performs reconstruction processing using a filtered back projection method, an iterative reconstruction method, or the like on the projection data generated by the preprocessing function 52 to generate CT image data. CT image data may also be called a reconstructed image. The reconstruction processing function 53 is an example of a reconstruction processing unit.

[0072] The image processing function 54 converts the CT image data generated by the reconstruction processing function 53 into tomographic image data of an arbitrary cross section or three-dimensional image data by a known method based on an input operation received from a user via the input interface 43. Note that the generation of the three-dimensional image data may be performed directly by the reconstruction processing function 53. The image processing function 54 is an example of an image processing unit.

[0073] The scan control function 55 controls the collection process of detection data in the gantry device 10 by issuing instructions to the X-ray high voltage device 14, the DAS 16, the bed driving device 34, etc. via the control device 18. The scan control function 55 controls the operation of each part when capturing a positioning image and performing the main image capture. The scan control function 55 is also an example of a scan control unit.

[0074] The display control function 56 displays information such as the estimated weight and the optimum amount of contrast agent to be administered to the subject P stored in the memory 41 and the memory 181, as well as information such as a GUI for receiving various operations from the user, on the display 42. The display control function 56 outputs information to the memory 41 and the memory 181 based on information received via the input interface 43. The display control function 56 is also an example of a display control unit.

[0075] Here, an example of the processing of the first embodiment executed by the processing circuitry 50 will be described with reference to FIGS. 6 and 7. FIG. 6 is a flowchart showing an example of the processing of the first embodiment executed by the processing circuitry 50 of FIG. 1. A rounded block such as S105 in the flowchart of FIG. 6 is processing executed by the user, and is not processing content by the X-ray CT apparatus 1 according to this embodiment. The order of processing in the flowchart described in FIG. 6 may be changed to the extent that it does not substantially affect the results, or processing may be performed in parallel to the extent that it does not substantially affect the results. FIG. 7 is a graph showing an example of change in the height position of the tabletop 31 in accordance with the processing of the flowchart shown in FIG. 6.

[0076] (Step S101) Before starting to use the X-ray CT apparatus 1, the processing circuitry 182 executes the necessity determination function 182c to determine whether or not the processes from step S102 to step S108 described below are necessary, that is, whether or not it is necessary to specify the weight of the subject P. If the determination result shows that the processes are necessary, the process proceeds to step S102. If the determination result shows that the processes are not necessary, the process proceeds to step S109 after the subject P is placed on the top board 31.

[0077] (Step S102) The processing circuit 182 turns off the brake device 38 using the brake control function 182b. Thereafter, the power control function 182a controls the bed drive device 34 to move the tabletop 31 from the initial position H0 to the contact position H1. An example of the change in the height position of the tabletop 31 from the initial position H0 to the contact position H1 is movement at a constant speed as shown in the graph in Figure 7. Even after the tabletop 31 has moved to the contact position H1, the brake control function 182b keeps the brake device 38 in the off state.

[0078] (Step S103) The processing circuit 182 turns off the bed drive device 34 using the power control function 182a. The tabletop 31 descends from the contact position H1 due to gravity acting on the tabletop 31. The tabletop 31 descends to a height position (tabletop weight holding position H2) where the elastic force corresponding to the elastic deformation generated in the elastic body 80 as the tabletop 31 descends and the gravity due to the weight of the tabletop 31 are balanced, and then stops. An example of the change in the height position of the tabletop 31 from the contact position H1 to the tabletop weight stopping position H2 is a movement accompanied by vibration due to expansion and contraction of the elastic body 80 until the tabletop 31 stops at the tabletop weight stopping position H2, as shown in the graph of FIG. 7.

[0079] (Step S104) The processing circuit 182 outputs the tabletop weight holding position H2 to the memory 181 by the height acquisition function 182d.

[0080] (Step S105) The user places the subject P on the top board 31. The top board 31 further descends from the top board weight holding position H2 due to the gravity caused by the weight of the subject P. The top board 31 descends to a height position (post-subject-placement stop position H3) where the elastic force caused by the elastic deformation of the elastic body 80 as the top board 31 descends balances with the gravity caused by the weight of the top board 31 and the subject P, and then stops. An example of the change in the height position of the top board 31 from the top board weight stop position H2 to the post-subject-placement stop position H3 is a movement accompanied by vibration caused by expansion and contraction of the elastic body 80 until the top board 31 stops at the post-subject-placement stop position H3, as shown in the graph of FIG. 7.

[0081] (Step S106) The processing circuitry 182 uses the height acquisition function 182d to output the stop position H3 after the subject is placed to the memory 181. Furthermore, the height acquisition function 182d reads out the initial position H0 and the stop position H3 after the subject is placed from the memory 181, and calculates the amount of displacement of the height position from the initial position H0 to the stop position H3 after the subject is placed. In this embodiment, this amount of displacement is called a subsidence amount, and this subsidence amount is output to the memory 181 by the height acquisition function 182d.

[0082] (Step S107) The processing circuit 182 outputs the total weight of the accessories placed on the top board 31 to the memory 181 by the accessory weight acquisition function 182e.

[0083] The processes in steps S106 and S107 may be performed in parallel, or the order of the processes may be reversed.

[0084] (Step S108) The processing circuit 182, using the estimation function 182f, acquires the amount of sinking from the memory 181. Thereafter, the estimation function 182f outputs to the memory 181 a weight value corresponding to the amount of sinking in the lookup table stored in the memory 181 as the weight (estimated weight) of the subject P placed on the top board 31. Furthermore, when the weight of the accessories is acquired in step S107, the estimation function 182f performs post-processing to update the estimated weight to a value obtained by subtracting the total weight of the accessories from the estimated weight stored in the memory 181.

[0085] 8 is an example of a lookup table that the estimation function 182f references in the memory 181 in step S108. In this lookup table, the amount of sinking corresponds to a weight value. The amounts of sinking a00, a01, a02, and a03 each have a different numerical value. The weight values ​​w00, w01, w02, and w03 may each have a different numerical value or may have some of the same numerical value. This is because when the difference in the amount of sinking is small, the weight values ​​are approximately the same.

[0086] (Step S109) The processing circuitry 182 uses the power control function 182a and the brake control function 182b to turn on the bed driving device 34 and the brake device 38. Thereafter, the processing circuitry 50 uses the scan control function 55 to execute positioning imaging or actual imaging based on the imaging conditions set by the user via the input interface 43.

[0087] Between steps S103 and S104 and between steps S105 and S106, vibrations in the height position of the tabletop 31 may occur due to expansion and contraction of the elastic body 80. As a countermeasure against such vibrations, a process may be added in which the execution of steps S104 and S106 is suspended for a predetermined period of time, or a process may be added in which the execution of steps S104 and S106 is suspended until the encoder 81 detects that the height position of the tabletop 31 has become constant.

[0088] In step S104, if there are no accessories attached to the top plate 31, the top plate weight holding position H2 is not acquired. This is because the top plate weight holding position H2 is at a constant height when there are no accessories attached to the top plate 31. On the other hand, if there are accessories attached to the top plate 31 in step S104, the top plate weight holding position H2 fluctuates depending on the weight of the accessories, so it is necessary to acquire the top plate weight holding position H2 each time. Therefore, the processing of step S104 will be explained separately for when no accessories are placed on the top plate 31 and when accessories are placed on the top plate 31.

[0089] First, the processing in step S104 when no accessories are placed on the tabletop 31 will be described. Unless the tabletop 31 is changed, the tabletop weight holding position H2 will be a constant value because it is a height position where the gravity corresponding to the weight of the tabletop 31 and the elastic force generated in the elastic body 80 are balanced. Therefore, by storing the tabletop weight holding position H2 when no accessories are placed on the tabletop 31 in the memory 181 in advance, the process of acquiring the tabletop weight holding position H2 in step S104 may be eliminated. Furthermore, in step S106, the height acquisition function 182d may read out the tabletop weight holding position H2 from the memory 181 and calculate the amount of sinking.

[0090] Next, the processing in step S104 when an accessory is placed on the tabletop 31 will be described. The tabletop weight holding position H2 is the height position of the tabletop 31 when the weight of the tabletop 31, gravity corresponding to the weight of the accessory, and the elastic force generated in the elastic body 80 are balanced, and therefore the tabletop weight holding position H2 varies depending on the weight of the accessory. Therefore, when an accessory is placed on the tabletop 31 in step S104, a lookup table corresponding to the tabletop weight holding position H2 may be stored in advance in memory 181, and the lookup table corresponding to the tabletop weight holding position H2 may be selected and referenced in step S106.

[0091] The first embodiment has been described above. In the X-ray CT apparatus 1 according to the first embodiment, the top 31 is controlled to descend from the top weight holding position H2 to the stop position H3 after the subject P is placed on the top 31 due to gravity acting on the subject P placed on the top 31, and a sinking amount, which is the amount of displacement of the height position of the top 31 from the top weight holding position H2 to the stop position H3 after the subject is placed on the top 31, is obtained. The estimation function 182f estimates the weight value corresponding to the sinking amount as the weight of the subject P placed on the top 31 using a lookup table.

[0092] The estimated weight, which is the result of estimating the weight of the subject P, is displayed on the display 42 by the display control function 56 and presented to the user, so that the user can set imaging conditions such as the amount of contrast agent administered, the X-ray dose, and the irradiation method for taking positioning images and actual imaging according to the estimated weight.

[0093] Furthermore, the calculation function 182g can calculate an optimum dose of the contrast agent from the estimated weight, and the optimum value can be displayed on the display 42 by the display control function 56 to present to the user. This allows the user to easily set an optimum dose of the contrast agent to be administered to the subject P.

[0094] Furthermore, the shape estimation function 182h can estimate the cross-sectional shape of the subject P from information combining the estimated weight with the height, age, and sex of the subject P. Furthermore, the position correction function 182i can calculate the amount of correction for the height position of the top 31 when capturing a positioning image and during the actual radiography from the cross-sectional shape of the subject P estimated by the shape estimation function 182h. This allows the user to easily adjust the height position of the top 31 when capturing a positioning image and during the actual radiography.

[0095] Hereinafter, an example will be described in which the weight of the subject P is estimated by placing the subject P on the top board 31 at the contact position H1 in this embodiment.

[0096] First, steps S101 and S102 are executed to move the top 31 to the contact position H1. Here, the user places the subject P on the top 31. The output of the bed driving device 34 is power that maintains the height position of the top 31 even if the braking device 38 is suddenly turned off due to a malfunction or the like, so the top 31 does not immediately descend even after the subject P is placed on it. Next, the power control function 182a gradually reduces the output of the bed driving device 34 until the bed driving device 34 is turned off, so that the top 31 descends to the stop position H3 after the subject is placed on it due to gravity caused by the weight of the subject P and the top 31.

[0097] The height acquisition function 182d acquires the amount of displacement of the height position of the top 31 from the contact position H1 obtained by the above control to the stop position H3 after the subject is placed. Here, the amount of displacement is taken as the amount of subsidence, and the estimation function 182f estimates the weight value corresponding to the amount of subsidence in the lookup table as the estimated weight. The estimated weight includes the weight of the top 31. Therefore, the estimation function 182f updates the estimated weight to the result obtained by subtracting the weight of the top 31 from the estimated weight from the memory 181. If it is necessary to subtract the weight of accessories, the estimation function 182f may further perform post-processing.

[0098] As explained above, the weight of the subject P placed on the top 31 can also be estimated by using the amount of sinking as the amount of displacement of the height position of the top 31 from the contact position H1 to the stop position H3 after the subject is placed on the top 31.

[0099] (Second embodiment) In this embodiment, from a state in which the X-link 71, to which the power of the bed drive device 34 is transmitted, holds the top 31 on which the subject P is placed, the power of the bed drive device 34 is temporarily reduced to lower the top 31, and then the power of the bed drive device 34 is increased to maintain the height position of the top 31. In this embodiment, an example will be described in which the weight of the subject P placed on the top 31 is estimated using a lookup table from information on the displacement amount of the height position of the top 31 during this control, the height position immediately before the top 31 is lowered, the power of the bed drive device 34 after the top 31 has been lowered, and the amount of change in the power of the bed drive device 34.

[0100] In the description of the second embodiment, differences from the first embodiment will be mainly described. Furthermore, the same components as those in the first embodiment will be denoted by the same reference numerals, and the description thereof may be omitted.

[0101] The processing circuit 182 included in the control device 18 of the X-ray CT apparatus 1 according to this embodiment further includes a power acquisition function 182j, which is different from the control device 18 of the X-ray CT apparatus 1 according to the first embodiment shown in Fig. 2. Furthermore, the bed device 30 of the X-ray CT apparatus 1 according to this embodiment differs from the bed device 30 of the X-ray CT apparatus 1 according to the first embodiment shown in Fig. 3 in that it includes a sensor 35.

[0102] First, differences between the control device 18 according to this embodiment and the control device 18 according to the first embodiment will be described. Fig. 9 is a block diagram showing an example of the configuration of the control device 18 according to the second embodiment.

[0103] In this embodiment, the memory 181 stores a lookup table that is different from the lookup table used in the first embodiment. Note that the lookup table will be described later.

[0104] The power control function 182a, braking control function 182b, necessity determination function 182c, height acquisition function 182d, accessory weight acquisition function 182e, estimation function 182f, calculation function 182g, shape estimation function 182h, position correction function 182i, and power acquisition function 182j of the processing circuit 182 are recorded in memory 181 in the form of computer-executable programs. The power control function 182a, braking control function 182b, necessity determination function 182c, height acquisition function 182d, accessory weight acquisition function 182e, calculation function 182g, shape estimation function 182h, position correction function 182i, and the like have the same functions in this embodiment as in the first embodiment, and therefore their explanations are omitted. Next, we will explain the power acquisition function 182j and the differences between the estimation function 182f in this embodiment and the estimation function 182f in the first embodiment.

[0105] The power acquisition function 182j estimates the power of the bed driving device 34 from the power information acquired from the sensor 35, and outputs the result of the estimation to the memory 181. The sensor 35 and the power information will be described later. The power acquisition function 182j can calculate the power, for example, by using a relational expression between the power information obtained in advance and the power of the bed driving device 34. The power acquisition function 182j may also output the amount of change from a reference power to the memory 181. The power acquisition function 182j is an example of a power acquisition unit.

[0106] In the present embodiment, the estimation function 182f also estimates the weight of the subject P placed on the top 31. The estimation function 182f outputs the weight (estimated weight) of the subject P placed on the top 31 to the memory 181, for example, by using a lookup table in which the height position of the top 31, the power of the bed driving device 34, and the amount of displacement of the power of the bed driving device 34 are associated with a plurality of weight values, in addition to the amount of displacement of the height position of the top 31 stored in the memory 181. In the present embodiment, the estimation function 182f also has a function of updating the estimated weight to one excluding the weight of accessories, similar to the estimation function 182f in the first embodiment.

[0107] Next, differences between the bed apparatus 30 according to this embodiment and the bed apparatus 30 according to the first embodiment will be described. Fig. 10 is a block diagram showing an example of the configuration of a bed apparatus 30a according to the second embodiment. The bed apparatus 30 according to this embodiment includes a sensor 35 in addition to the components of the bed apparatus 30 according to the first embodiment.

[0108] The sensor 35 detects power information required to estimate the power of the bed drive device 34. The power information is, for example, the current flowing through the bed drive device 34 when the bed drive device 34 rotates the lead screw 36. The sensor 35 is, for example, a current sensor that detects the value of the current flowing through the bed drive device 34. The sensor 35 may be included in the configuration of the bed drive device 34 or may be configured as a separate entity from the bed drive device 34.

[0109] Here, an example of the processing of the second embodiment executed by the processing circuitry 182 and the processing circuitry 50 will be described using FIGS. 11 and 12. FIG. 11 is a flowchart showing an example of the processing of the second embodiment executed by the processing circuitry 182 and the processing circuitry 50. A rounded block such as S201 in the flowchart of FIG. 11 is processing executed by the user, not processing content by the X-ray CT apparatus 1 according to this embodiment. The order of processing in the flowchart described in FIG. 11 may be changed to the extent that it does not substantially affect the results, or processing may be performed in parallel to the extent that it does not substantially affect the results. FIG. 12 is a graph showing an example of a change in the height position of the tabletop 31 in accordance with the processing of the flowchart shown in FIG. 11.

[0110] (Step S201) The user places the subject P on the tabletop 31. In step S201, the braking device 38 is on. The height position of the tabletop 31 is maintained at the initial position H0. Furthermore, the bed driving device 34 outputs a force (initial position maintaining torque T1) that maintains the height position of the tabletop 31 even if the braking device 38 is suddenly turned off due to a malfunction or the like.

[0111] (Step S202) The processing circuitry 182 executes the necessity determination function 182c to determine whether or not the processes from step S203 to step S211 described below are necessary, that is, whether or not it is necessary to specify the weight of the subject P. If the determination result indicates that the processes are necessary, the process proceeds to step S203. If the determination result indicates that the processes are not necessary, the process proceeds to step S212.

[0112] (Step S203) The processing circuitry 182 executes the height acquisition function 182d to output the initial position H0, which is the height position of the tabletop 31, to the memory 181.

[0113] (Step S204) The processing circuit 182 uses the brake control function 182b to turn off the brake device 38. Furthermore, the processing circuit 182 uses the power control function 182a to cause the bed driving device 34 to maintain the output of the initial position holding torque T1. As a result, the height position of the tabletop 31 is maintained.

[0114] (Step S205) The processing circuit 182 executes the power acquisition function 182j and outputs the initial position holding torque T1 to the memory 181.

[0115] The processes of steps S203, S204, and S205 may be performed in parallel, or the order of the processes may be reversed.

[0116] (Step S206) The processing circuit 182, using the power control function 182a, causes the bed driving device 34 to maintain the output of power (descent start torque T4) that is reduced by a certain amount from the initial position holding torque T1. As a result, the tabletop 31 descends from the initial position H0. The height position of the tabletop 31 drops sharply as shown in the graph of FIG. 12. An example of the relationship between the initial position holding torque T1 and the descent start torque T4 is shown in the graph of FIG. 12. The descent start torque T4 is an example of the power that lowers the tabletop 31.

[0117] (Step S207) When the tabletop 31 reaches a descent detection position H5, which is a certain value lower than the initial position H0, the encoder 81 detects a change in the height position of the tabletop 31. Thereafter, the power control function 182a increases the output of the bed driving device 34 from the descent start torque T4 until the tabletop 31 stops.

[0118] One example of how the output of the bed drive device 34 is increased in step S207 is as shown in the graph of FIG. 12. The faster the descent speed of the tabletop 31, the greater the increase in the output of the bed drive device 34; the slower the descent speed of the tabletop 31, the smaller the increase in the output of the bed drive device 34. When the output of the bed drive device 34 is switched from the descent start torque T4 to a constant value larger output (output T5) and maintained like a step function, if the output T5 is appropriate, the tabletop 31 stops. However, if the output T5 is excessive, the tabletop 31 begins to rise, and if the output T5 is insufficient, the descent continues. This is due to the characteristics of the X-link 71: the higher the height position of the tabletop 31, the less power is required to hold and raise it; and the lower the height position of the tabletop 31, the greater the power required to hold and raise it. For these reasons, it is preferable to increase the output of the bed drive device 34 according to the descent speed of the tabletop 31, as described above.

[0119] (Step S208) The processing circuitry 182 uses the height acquisition function 182d to output the height position of the top 31 when the descent of the top 31 stops (stop position H3 after the subject is placed) to the memory 181. Furthermore, the height acquisition function 182d reads out the initial position H0 and the stop position H3 after the subject is placed from the memory 181, and calculates the amount of displacement of the height position from the initial position H0 to the stop position H3 after the subject is placed. In this embodiment, this amount of displacement is called the subsidence amount, and this subsidence amount is output to the memory 181 by the height acquisition function 182d.

[0120] (Step S209) The processing circuitry 182 outputs, via the power acquisition function 182j, the power (stop position holding torque T3) of the bed drive device 34 when the top 31 is held at the stop position H3 after the subject is placed, to the memory 181. Furthermore, the power acquisition function 182j reads out the initial position holding torque T1 and the stop position holding torque T3 from the memory 181, and calculates the amount of change from the initial position holding torque T1 to the stop position holding torque T3. In this embodiment, this amount of change is called a holding torque change amount, and this holding torque change amount is output to the memory 181 by the power acquisition function 182j.

[0121] The stop position holding torque T3 is greater than the initial position holding torque T1 because the lower the height position of the top board 31, the greater the power required to hold and lift it.

[0122] The processes of steps S208 and S209 may be performed in parallel, or the order of the processes may be reversed.

[0123] (Step S210) The processing circuit 182 uses the accessory weight acquisition function 182e to output the total weight of the accessories placed on the top board 31 to the memory 181. Note that step S210 may be processed in parallel with the processing from step S203 to step S209, or the order of the processing may be reversed.

[0124] (Step S211) The processing circuit 182, using the estimation function 182f, acquires the amount of sinking, the initial position H0, the stop position holding torque T3, and the holding torque change amount from the memory 181. Thereafter, the estimation function 182f outputs weight values ​​corresponding to the amount of sinking, the initial position H0, the stop position holding torque T3, and the holding torque change amount in the lookup table stored in the memory 181 to the memory 181 as the weight (estimated weight) of the subject P placed on the top board 31. Furthermore, when the weight of the accessories is acquired in step S210, the estimation function 182f performs post-processing to update the estimated weight to a value obtained by subtracting the total weight of the accessories from the estimated weight stored in the memory 181.

[0125] FIG. 13 shows an example of a lookup table referenced by the estimation function 182f in step S210. In this lookup table, the amount of subsidence, initial position H0, stop position holding torque T3, and holding torque change amount are associated with weight values. Different values ​​are entered for the amounts of subsidence a10 and a11. Meanwhile, the initial positions h10 and h11, the stop position holding torques x10, x11, and x12, and the holding torque change amounts y11 and y12 may be partially identical or different. This is to cover all possible combinations of the amount of subsidence, initial position H0, stop position holding torque T3, and holding torque change amount. Furthermore, the weight values ​​wa10, wa11, wb10, wb11, wc10, wd10, wd11, wd12, we10, we11, and we12 may be partially identical or different. The reason is that even if the conditions of the sinking amount, the initial position H0, the stop position holding torque T3, and the holding torque change amount change, the change in the weight value may be approximately the same.

[0126] (Step S212) The processing circuitry 182 uses the power control function 182a and the brake control function 182b to turn on the bed driving device 34 and the brake device 38. Thereafter, the processing circuitry 50 uses the scan control function 55 to execute positioning imaging or actual imaging based on the imaging conditions set by the user via the input interface 43.

[0127] The second embodiment has been described above. According to the second embodiment, as described above, the X-ray CT apparatus 1 according to this embodiment controls the top 31 to descend from the initial position H0 to the stop position H3 after the subject P is placed thereon, without limiting the height position of the top 31 when the subject P is placed thereon to below the contact position H1. This allows the user to select the height of the top 31 when the subject P is placed thereon according to the situation, and then obtain the weight of the subject P from the bed apparatus 30.

[0128] (Third embodiment) In this embodiment, when the subject P is placed on the top 31 while the top 31 is being held by the X-link 71 to which the power of the bed drive device 34 is transmitted, the top 31 descends. The power of the bed drive device 34 is then increased to hold the top 31 in place. This example describes an example in which the weight of the subject P placed on the top 31 is estimated using a lookup table based on information on the displacement of the height position of the top 31 during the above control, the height position immediately before the top 31 descends, the power of the bed drive device 34 after the top 31 descends, and the change in the power of the bed drive device 34. The following description focuses mainly on the differences from the first and second embodiments. Since the configuration of this embodiment is similar to that of the second embodiment, the same reference numerals are used and a description thereof will be omitted.

[0129] Here, an example of the processing of the third embodiment executed by the processing circuitry 182 and the processing circuitry 50 will be described using FIGS. 14 and 15. FIG. 14 is a flowchart showing an example of the processing of this embodiment executed by the processing circuitry 182 and the processing circuitry 50. A rounded block such as S306 in the flowchart of FIG. 14 represents processing executed by the user, not processing content by the X-ray CT apparatus 1 according to this embodiment. The order of processing in the flowchart described in FIG. 14 may be changed to the extent that it does not substantially affect the results, or processing may be performed in parallel to the extent that it does not substantially affect the results. FIG. 15 is a graph showing an example of changes in the height position of the tabletop 31 in accordance with the processing of the flowchart shown in FIG. 14.

[0130] (Step S301) Before starting to use the X-ray CT apparatus 1, the processing circuitry 182 executes the necessity determination function 182c to determine whether or not the processes from step S302 to step S311 described below are necessary, that is, whether or not it is necessary to specify the weight of the subject P. If the determination result shows that the processes are necessary, the process proceeds to step S302. If the determination result shows that the processes are not necessary, the process proceeds to step S312 after the subject P is placed on the top board 31.

[0131] (Step S302) The processing circuit 182 uses the height acquisition function 182d to output the height position of the tabletop 31 as the initial position H0 to the memory 181. Note that the power of the bed driving device 34 in step S302 is set to an initial position torque T0.

[0132] (Step S303) The processing circuit 182 turns off the brake device 38 via the brake control function 182b.

[0133] The processes of steps S302 and S303 may be performed in parallel, or the order of the processes may be reversed.

[0134] (Step S304) The processing circuit 182, using the power control function 182a, reduces the power of the bed driving device 34 from the initial position torque T0 to a power (top weight holding torque T2) that lowers the top 31 when the subject P is placed on the top. The top weight holding torque T2 is an example of a power that lowers the top 31.

[0135] (Step S305) The processing circuit 182 outputs the tabletop weight holding torque T2 to the memory 181 by the power acquisition function 182j.

[0136] (Step S306) The user places the subject P on the top board 31. After that, the top board 31 is lowered from the initial position H0.

[0137] (Step S307) When the tabletop 31 reaches a descent detection position H5, which is a certain value lower than the initial position H0, the encoder 81 detects a change in the height position of the tabletop 31. After that, the power control function 182a increases the power of the bed drive device 34 from the tabletop weight holding torque T2 until the tabletop 31 stops.

[0138] One example of how to increase the output of the bed drive device 34 in step S307 is to increase the amount of increase in the output of the bed drive device 34 as the speed at which the tabletop 31 descends increases, and decrease the amount of increase in the output of the bed drive device 34 as the speed at which the tabletop 31 descends decreases, as shown in the graph of Fig. 15. The reason why it is preferable to increase the output of the bed drive device 34 in accordance with the speed at which the tabletop 31 descends is as described in the explanation of step S207.

[0139] (Step S308) The processing circuitry 182 uses the height acquisition function 182d to output the height position of the top 31 when the descent of the top 31 stops (stop position H3 after the subject is placed) to the memory 181. Furthermore, the height acquisition function 182d reads out the initial position H0 and the stop position H3 after the subject is placed from the memory 181, and calculates the amount of displacement of the height position from the initial position H0 to the stop position H3 after the subject is placed. In this embodiment, this amount of displacement is called the subsidence amount, and this subsidence amount is output to the memory 181 by the height acquisition function 182d.

[0140] (Step S309) The processing circuitry 182 uses the power acquisition function 182j to output the power (stop position holding torque T3) of the bed drive device 34 when the top 31 is held at the stop position H3 after the subject is placed to the memory 181. Furthermore, the power acquisition function 182j reads out the top weight holding torque T2 and the stop position holding torque T3 from the memory 181, and calculates the amount of change from the top weight holding torque T2 to the stop position holding torque T3. In this embodiment, this amount of change is called the holding torque change amount, and this holding torque change amount is output to the memory 181 by the power acquisition function 182j.

[0141] The processes of steps S308 and S309 may be performed in parallel, or the order of the processes may be reversed.

[0142] (Step S310) The processing circuit 182 uses the accessory weight acquisition function 182e to output the total weight of the accessories placed on the top board 31 to the memory 181. Note that step S310 may be processed in parallel with the processing from step S307 to step S309, or the order of the processing may be reversed.

[0143] (Step S311) The processing circuit 182, using the estimation function 182f, acquires the amount of sinking, the initial position H0, the stop position holding torque T3, and the holding torque change amount from the memory 181. Thereafter, the estimation function 182f outputs weight values ​​corresponding to the amount of sinking, the initial position H0, the stop position holding torque T3, and the holding torque change amount from the lookup table stored in the memory 181 to the memory 181 as the weight (estimated weight) of the subject P placed on the top board 31. Furthermore, when the weight of the accessories is acquired in step S310, the estimation function 182f performs post-processing to update the estimated weight to a value obtained by subtracting the total weight of the accessories from the estimated weight stored in the memory 181.

[0144] In S311, an example of the lookup table referred to by the estimation function 182f is shown in Fig. 13, as in the second embodiment. In the lookup table, the sinking amount, the initial position H0, the stop position holding torque T3, and the holding torque change amount are associated with the estimated weight.

[0145] (Step S312) The processing circuitry 182 uses the power control function 182a and the brake control function 182b to turn on the bed driving device 34 and the brake device 38. Thereafter, the processing circuitry 50 uses the scan control function 55 to execute positioning imaging or actual imaging based on the imaging conditions set by the user via the input interface 43.

[0146] The third embodiment has been described above. According to the third embodiment, as described above, the X-ray CT apparatus 1 according to this embodiment controls the top 31 to descend from the initial position H0 to the stop position H3 after the subject is placed thereon without limiting the height position of the top 31 to the contact position H1 or lower when the subject P is placed thereon, and also receives a request for the control and weight estimation before the subject P is placed on the top 31. This allows the X-ray CT apparatus 1 according to this embodiment to reduce the number of steps required for weight estimation after the subject P is placed on the top 31. As a result, even in an emergency or other situation where an estimated weight of the subject P needs to be obtained in a shorter time, the user can select imaging including weight estimation by having the X-ray CT apparatus 1 prepare for weight estimation before placing the subject P on the top 31.

[0147] In the second and third embodiments, too, by executing the display control function 56, the user can determine imaging conditions such as the amount of contrast agent administered, the X-ray dose, and the irradiation method for capturing positioning images and the actual imaging, depending on the weight of the subject P. In the second and third embodiments, the calculation function 182g allows the user to easily set imaging conditions for administering an appropriate amount of contrast agent. Furthermore, in the second and third embodiments, the shape estimation function 182h and the position correction function 182i allow the user to easily adjust the height position of the tabletop 31 for capturing positioning images and the actual imaging.

[0148] (Fourth embodiment) In the first to third embodiments described above, examples have been described in which the weight of the subject P is estimated using a medical image diagnostic apparatus. In this embodiment, an example will be described in which a bed apparatus alone performs processing equivalent to the weight estimation of the subject P in the medical image diagnostic apparatus according to the first embodiment, and transmits the result of the estimation to a medical image diagnostic apparatus that is communicably connected. Note that the description of this embodiment will mainly focus on differences from the first embodiment. Furthermore, the same reference numerals will be used to designate components similar to those in the first embodiment, and descriptions thereof may be omitted.

[0149] 16 is a block diagram showing an example of the configuration of a bed apparatus 30a according to the fourth embodiment. In addition to the configuration of the bed apparatus 30 according to the first embodiment, the bed apparatus 30a according to this embodiment includes a memory 181a, a processing circuit 183, a camera 20a, a display 42a, and an input interface 43a, which correspond to the memory 181, the processing circuit 182, the camera 20, the display 42, and the input interface 43 according to the first embodiment, respectively. The power control function 183a, the braking control function 183b, the necessity determination function 183c, the height acquisition function 183d, the accessory weight acquisition function 183e, the estimation function 183f, the calculation function 183g, the shape estimation function 183h, the position correction function 183i, and the display control function 183j correspond to the power control function 182a, the braking control function 182b, the necessity determination function 182c, the height acquisition function 182d, the accessory weight acquisition function 182e, the estimation function 182f, the calculation function 182g, the shape estimation function 182h, the position correction function 182i, and the display control function 56 in the first embodiment, respectively. Furthermore, the bed device 30a according to this embodiment further includes a communication device 90.

[0150] The communication device 90 communicates data with devices connected via a network NW. The communication device 90 is a wireless or wired interface for communicating with the outside world, and is realized, for example, by a network card, a network adapter, or a network interface controller (NIC). The network NW refers to the entire information and communication network using electronic communication technology, and includes Internet networks such as a hospital backbone LAN, a wireless LAN, and a wired LAN, as well as telephone communication networks, optical fiber communication networks, cable communication networks, and satellite communication networks. The device is, for example, a medical image diagnostic device and an RIS. The communication device 90 transmits information generated by each function of the processing circuit 183, such as estimated weight, an optimum contrast agent amount, and a position correction amount, to the device. The communication device 90 receives, for example, a control signal for the bed device 30a during imaging from the medical image diagnostic device. The communication device 90 is also an example of a communication unit.

[0151] With the configuration described above, the bed apparatus 30a according to this embodiment also performs the same process as the flowchart shown in Fig. 6 to obtain an estimated weight. Furthermore, the bed apparatus 30a transmits the estimated weight to the medical image diagnostic apparatus via the communication device 90.

[0152] In the bed device 30a, the calculation function 183g calculates an appropriate amount of contrast agent according to the weight of the subject P, and the shape estimation function 183h and the position correction function 183i acquire the position correction amount for the height position of the tabletop 31 during positioning image capture and actual image capture. The bed device 30a can transmit the appropriate amount of contrast agent and the position correction amount to the medical image diagnostic device via the communication device 90. From these, the user can determine imaging conditions such as the contrast agent dose, X-ray dose, and irradiation method during positioning image capture and actual image capture according to the weight of the subject P using the medical image diagnostic device.

[0153] Furthermore, the bed device 30a can control the bed device 30a in a way that is suitable for imaging by receiving imaging conditions set by the user in the medical image diagnostic device from the medical image diagnostic device via the communication device 90. This allows the user to use the bed device 30a during imaging.

[0154] (Fifth embodiment) In this embodiment, an example will be described in which the bed device 30b alone performs processing equivalent to estimating the weight of the subject P in the medical image diagnostic apparatus according to the second and third embodiments, and transmits the result of the estimation to the medical image diagnostic apparatus that is communicably connected. Note that the description of this embodiment will mainly focus on differences from the second and third embodiments. Furthermore, the same reference numerals will be used to designate components similar to those in the second and third embodiments, and descriptions thereof may be omitted.

[0155] 17 is a block diagram showing an example of the configuration of a bed apparatus 30b according to this embodiment. The bed apparatus 30b according to this embodiment includes the memory 181a, processing circuit 183, camera 20a, display 42a, and input interface 43a, which correspond to the memory 181, processing circuit 182, camera 20, display 42, and input interface 43a according to the second embodiment, in addition to the configuration of the bed apparatus 30a, and further includes a communication device 90. That is, the bed apparatus 30b according to this embodiment includes a sensor 35 and a power acquisition function 183k in addition to the configuration of the bed apparatus 30a. The power acquisition function 183k of the processing circuit 183 corresponds to the power acquisition function 182j according to the second embodiment.

[0156] With the configuration described above, the bed apparatus 30b according to this embodiment can also perform processing equivalent to the flowcharts shown in FIGS. 11 and 14 to obtain an estimated weight. That is, the bed apparatus 30b can perform processing equivalent to the weight estimation of the subject P in the medical image diagnostic apparatus according to the second and third embodiments. Furthermore, like the bed apparatus 30a, the bed apparatus 30b according to this embodiment can transmit the estimated weight, the optimum amount of contrast agent, and the position correction amount to the medical image diagnostic apparatus. As a result, the user can determine imaging conditions, such as the amount of contrast agent administered, the X-ray dose, and the irradiation method, for capturing positioning images and actual imaging, depending on the weight of the subject P, using the medical image diagnostic apparatus.

[0157] In the bed device 30b, the calculation function 183g calculates the optimum amount of contrast agent according to the weight of the subject P, and the shape estimation function 183h and the position correction function 183i acquire the position correction amount for the height position of the tabletop 31 during positioning image capture and actual image capture. The bed device 30a can transmit the optimum amount of contrast agent and the position correction amount to the medical image diagnostic device via the communication device 90. From these, the user can determine imaging conditions such as the contrast agent dose, X-ray dose, and irradiation method during positioning image capture and actual image capture according to the weight of the subject P using the medical image diagnostic device.

[0158] Furthermore, like the bed device 30a, the bed device 30b can receive imaging conditions set by the user in the medical image diagnostic device from the medical image diagnostic device, allowing the user to use the bed device 30b during imaging.

[0159] According to at least one of the embodiments described above, the weight of the subject P placed on the top board 31 can be obtained using the sinking amount, which is the amount of displacement of the height position of the top board 31. In this way, in the X-ray CT apparatus 1, bed apparatus 30a, and bed apparatus 30b according to this embodiment, the weight of the subject can be measured by the bed apparatus.

[0160] Although several embodiments have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These embodiments can be implemented in various other forms, and various omissions, substitutions, modifications, and combinations of embodiments can be made without departing from the spirit of the invention. These embodiments and their modifications are included within the scope and spirit of the invention, as well as within the scope of the invention and its equivalents as defined in the claims. [Explanation of symbols]

[0161] 1 X-ray CT device 30 Bed Device 30a Bed Device 30b Bed Device 31 Top plate 34 Bed drive unit 35 sensors 36 Lead screw 37 Nut 38 Braking device 71 X-Link 80 Elastic Body 90 Communication Equipment 182a Power control function 182b Braking control function 182c Necessity judgment function 182d Height acquisition function 182e Accessory weight acquisition function 182f Estimation Function 182g calculation function 182h Shape estimation function 182i position correction function 182j Power acquisition function 183a Power control function 183b Braking control function 183c Necessity determination function 183d height acquisition function 183e Accessory weight acquisition function 183f Estimation Function 183g Calculation Function 183h Shape estimation function 183i position correction function 183k power acquisition function

Claims

1. a top plate on which a subject is placed; an elastic body provided between the top plate and the floor surface; a lifting mechanism for lifting and lowering the top plate; a power unit that provides power to the lifting mechanism to hold or lift the tabletop; a power control unit that controls the power unit so that the top plate is lowered until a balance is reached between gravity acting on the subject in accordance with the weight of the subject placed on the top plate and an elastic force acting on the elastic body that is elastically deformed by being pressed by the top plate; and an estimation unit that estimates an estimated weight, which is the weight of the subject, based on the amount of displacement of the height position of the tabletop under the control; A medical image diagnostic device comprising:

2. the estimation unit estimates the estimated weight based on a lookup table in which the displacement amount and a weight value are associated with each other. The medical image diagnostic apparatus according to claim 1 .

3. The lifting mechanism further includes a base to which an end opposite to the end connected to the top plate is connected, the elastic body is provided so that one end is fixed to either the top plate or the base and the other end faces the other of the top plate or the base, the displacement amount is a difference between a height position at which the elastic body holds the top plate without the subject placed thereon under the control and a height position at which the elastic body, elastically deformed by being pressed by the top plate, holds the top plate with the subject placed thereon.

3. The medical image diagnostic apparatus according to claim 1.

4. The estimation unit estimates the estimated weight further based on a change in the power for holding the tabletop under the control. The medical image diagnostic apparatus according to claim 1 .

5. the estimation unit estimates the estimated weight based on a lookup table in which the displacement amount, the change amount of the power, and a weight value are associated with each other. The medical image diagnostic apparatus according to claim 4.

6. the displacement amount is a difference between a height position at which the lifting mechanism holds the top plate when the subject is not placed thereon and a height position at which the lifting mechanism holds the top plate when the subject is placed thereon.

6. The medical image diagnostic apparatus according to claim 4 or 5.

7. the amount of change is a difference between a power required to hold the tabletop on which the subject is placed and a power required to hold the tabletop on which the subject is placed at the end of the control. The medical image diagnostic apparatus according to any one of claims 4 to 6.

8. the amount of change is a difference between a power for holding the tabletop under the control and a power for holding the tabletop on which the subject is placed at the end of the control. The medical image diagnostic apparatus according to any one of claims 4 to 6.

9. An accessory weight acquisition unit that acquires the weight of the accessory placed on the top plate is further provided, the estimation unit updates the estimated weight to a value obtained by subtracting the weight of the accessory from the estimated weight. The medical image diagnostic apparatus according to any one of claims 1 to 8.

10. a calculation unit that calculates an appropriate amount of contrast agent to be administered to the subject based on the estimated weight; The medical image diagnostic apparatus according to any one of claims 1 to 9.

11. further comprising a shape estimation unit that estimates a shape of the subject based on the estimated weight. The medical image diagnostic apparatus according to any one of claims 1 to 10.

12. a position correction unit that corrects the height position of the tabletop based on the shape of the subject; The medical image diagnostic apparatus according to claim 11.

13. a top plate on which a subject is placed; an elastic body provided between the top plate and the floor surface; a lifting mechanism for lifting and lowering the top plate; a power unit that provides power to the lifting mechanism to support or lift the top plate; a power control unit that controls the power unit so that the top plate is lowered until a balance is reached between gravity acting on the subject in accordance with the weight of the subject placed on the top plate and an elastic force acting on the elastic body that is elastically deformed by being pressed by the top plate; and an estimation unit that estimates an estimated weight, which is the weight of the subject, based on the amount of displacement of the height position of the tabletop under the control; A sleeper device comprising:

14. a communication unit that transmits the estimated weight to a device that is communicatively connected to the communication unit; The sleeper apparatus according to claim 13.

Images